Multi-functional material having photo-catalytic function and production method therefor

Multifunctional material with photocatalytic function and manufacturing method thereof

The invention relates to a multifunctional material having a function of deodorizing function, antibacterial function, sterilization function, antifouling function and the like and a manufacturing method thereof.

In the past, by irradiating ultraviolet rays, it is possible to cause adsorption or desorption of oxygen atoms to organic compounds such as malodorous components to promote decomposition (oxidation).₂, V₂O₅, ZnO, WO₃Etc., especially the crystalline form of anatase TiO₂The particle system has a high photocatalytic effect, so it has been proposed in the past to form a photocatalyst layer on the surface of a wall material, a tile, a glass (mirror), a circulation filter device or a sanitary ware.

In the method of forming the photocatalyst layer, a conventional method is to form a TiO directly on the surface of a substrate such as a plastic, a ceramic, or a resin by a CVD method, a sputtering method, an electron beam evaporation method, or the like.₂A photocatalyst layer formed by particles or the like.

However, when a CVD method, a sputtering method, an electron beam evaporation method, or the like is used, it is necessary to have a scale device, and the yield of the product is also poor, and the manufacturing cost is high.

Further, in another method of forming a photocatalyst layer, a conventional method is also known in which a photocatalyst particle is kneaded on a binder, applied to a surface of a substrate by a spraying method, or subjected to dip coating by a dip coating method, and then subjected to heat treatment. Method (Japanese Patent Laid-Open No. Hei 5-201747).

TiO₂When a photocatalyst particle such as a particle is to be used as a photocatalyst, it is necessary to irradiate ultraviolet light to the photocatalyst particle, and the photocatalyst particle must be in contact with a substance to be decomposed by a malodorous gas, as disclosed in Japanese Laid-Open Patent Publication No. Hei 5-201747, the kneading photocatalyst particle is stuck. When the coating agent is applied to the substrate, most of the photocatalyst particles are buried in the binder layer, and ultraviolet rays may not be irradiated, and the malodorous substances may not be in contact with each other.

Further, another method for forming a photocatalyst layer is alkoxide method disclosed in Japanese Laid-Open Patent Publication No. Hei 5-7394. In this method, a titanium alkoxide is coated on a glass substrate, dried, and fired at a temperature of 100 ° C to form a photocatalyst layer, and the photocatalyst layer is irradiated with ultraviolet rays to decompose the organic substance in the water.

The above alkoxide method has the advantage of being able to form a film at a lower temperature, and is effective as a raw material which does not soften at about 500 ° C as a base material such as pyrex glass or quartz glass. However, when a material having a low melting point such as soda glass is used as a substrate, the substrate is softened at a temperature at which the film is formed, and the formed photocatalyst film is buried in the substrate, so that the light cannot reach the photocatalyst layer. The use of photocatalytic functions is a disadvantage for them.

Further, in Japanese Laid-Open Patent Publication No. H1-288331, it is disclosed that TiO is sprayed.₂Sol-coated on ceramic paper of fibrous material, after heat treatment at 400~700 °C, spray SnO₂The sol is heat-treated at 400 to 700 ° C to form a photocatalyst layer which can enhance the oxidative decomposition of the aldehyde.

The entire surface of the film is less active than TiO when the method disclosed in Japanese Patent Publication No. Hei 1-288321₂SnO₂Covered. In addition, cracking is likely to occur when the film strength is to be increased. That is, as shown in FIG. 1(a), the surface of the tile 100 is coated with TiO.₂When the sol of the particle 101 is further heat-treated (sintered), the crack 102 as shown in Fig. 1(b) occurs. According to the speculation, the volume shrinkage (increased density) will occur when the phase is transferred to rutile. Before sintering, as shown in Fig. 2(a), TiO₂The interval between the grains 101 is L₀After sintering to the rutile type, as shown in Fig. 2(b), the volume will spread to the other side, and the interval between the particles will be shortened to L.₁(L₁<L₀), resulting in cracks.

On the other hand, Japanese Patent Publication No. 4-46609 discloses a method for decomposing the odorous substance contained in ozone in the air in the vehicle or improving the quality thereof to purify the ozone in the vehicle, and irradiating the light to the semiconductor carrying metal or metal oxide. The solid photocatalyst on the semiconductor, at the same time, the air in the car to be cleaned is contacted with the photocatalyst, and the ozone odorous substance contained in the air is decomposed by photochemical reaction, or the ozone purification method in the vehicle is characterized by improving its quality.

For example, when a substrate coated with a photocatalyst on the surface of a substrate is used in an environment such as sewage or an outer wall, it is easy to adhere to dirt, dust, bacteria, etc. contained in the atmosphere or in water, and sometimes adheres. The type of dirt reduces the photocatalytic function.

In the past, in order to reduce the function of the photocatalyst due to the adhesion of dirt, the Japanese Patent No. 6-7905 proposes countermeasures. This publication discloses that a photocatalyst layer formed by a semiconductor is provided, and an ultraviolet lamp and a heating element provided therewith are formed by a blower, and the entire photocatalyst layer can be sequentially heated to make the photocatalyst layer or the heating element, or the photocatalyst layer and the heating element can be By moving the photocatalyst to deodorize the device, by heating to about 400 ° C, the polymer and the dirt caused by the dust are removed, and the photocatalyst layer can be regenerated.

However, the method of regenerating the photocatalyst layer is not easy to apply to the member used in the equipment installed in the room. Therefore, the fundamental solution should not be to remove the dirt from the photocatalyst layer and remove it. It is necessary to develop a photocatalyst layer that is not easily stained, or to develop a function that does not reduce the photocatalyst function even if it is stained.

Further, Japanese Patent Publication No. 6-7906 discloses a method of irradiating light of a strong ultraviolet ray intensity to a photocatalyst to remove odor from a home or an office. However, when the light of strong ultraviolet intensity is irradiated, different odor decomposition rates are caused by the structure of the photocatalyst. Further, in the above prior art, the base material is porous, and sufficient mechanical strength can be obtained by impregnation or the like, but the base material is glazed tile, and the dense ceramic is not porous, so it is not sufficient. Mechanical strength.

Also, TiO₂Among them, there are different crystal types such as anatase, perovskite and rutile. Moreover, the photoactivity is better, the anatase type is better, and the other crystal types are not light, and according to the magazine. Surface 1987, Volume 25 has reported that rutile TiO₂When it can carry platinum, silver and other metals, it can improve the photoactivity, but the malodor removal rate, compactness and adhesion are still insufficient. Especially when silver or silver oxide is used as the additive metal, these factors are black and are not suitable for tiles or building materials.

Further, since the titanium oxide sol produced by the hydrothermal method or the sulfuric acid method is formed of ultrafine particles, it is extremely easy to aggregate. When the agglomerate is applied to the surface of the substrate, it may become uneven in gloss and cause cracking. For this reason, in order to prevent aggregation thereof, a method of attaching an organic dispersant such as triethanolamine to the surface of the titanium oxide sol has been used.

The titanium oxide sol obtained by a method of adhering an organic dispersant such as triethanolamine to the surface of the titanium oxide sol is applied to a substrate having low heat resistance such as a resin substrate.

When it is fixed at 300 ° C or lower, the organic dispersant is firmly fixed to the active site of the titanium oxide sol, and cannot be sufficiently evaporated and decomposed in the firing process. Therefore, the material obtained by this method does not have sufficient photocatalytic action. Nor is it adequately deodorant or antibacterial.

Japanese Laid-Open Patent Publication No. Hei 5-253544 discloses a method of kneading an anatase type titanium oxide on a binder and applying it to a surface of a substrate for heat treatment. The method forms an adhesive layer on the surface of the material material of the wall surface or the ceiling surface of the living house, and the surface of the adhesive layer is sprayed to a part of the photocatalyst mainly composed of anatase type titanium oxide. The fine powder is exposed to the adhesive layer, and then heated at a temperature of 300 ° C or more and 900 ° C or less to melt the adhesive layer, and then cooled to fix the adhesive layer.

However, in this method, when the heat treatment is performed at 300 ° C or higher and 900 ° C or lower, the deodorizing property can be improved, but at a low temperature of 300 ° C or lower, good deodorizing properties cannot be obtained. Therefore, it is extremely difficult to add a good photocatalytic activity such as excellent deodorizing property to a substrate such as a plastic having no heat resistance. It is presumed that the reason is that when the photocatalyst particles are to be uniformly applied to the substrate, the photocatalyst particles must be monodispersed in the suspension in the preliminary step, and an organic dispersant is added thereto, and the dispersant is at 300 ° C. The following is not sufficiently decomposed, vaporized, and remains to cover the active sites on the photocatalyst particles.

Therefore, the present invention provides a photocatalyst layer which can be exposed to the surface of the substrate, and can sufficiently exhibit the photocatalytic effect, and can be used as a material having excellent versatility because the photocatalyst layer is retained on the substrate.

Further, the present invention has an object of forming a photocatalyst layer which is not easily peeled off on a relatively dense substrate such as glass, tile, metal or plastic.

Further, the present invention is aimed at forming a photocatalyst layer on a substrate having a low melting point, for example, on a relatively inexpensive and easily processable soda glass.

Further, the present invention has an object of providing a multifunctional material which is less likely to adhere to dirt, has a function of reducing dirt due to dirt, has antibacterial property or odor resistance, and is excellent in mechanical strength.

Moreover, the present invention provides even anatase TiO₂As the main photocatalyst layer, it can still be used as a multifunctional material with excellent peel strength.

Moreover, the present invention is to improve rutile TiO₂For the purpose of photocatalytic activity of the photocatalyst layer of the main body.

Moreover, the present invention is supported by rutile TiO in silver.₂It is the photocatalyst layer of the main body to enhance the photocatalytic activity, and at the same time, decolorize the photocatalyst layer to improve its appearance.

Further, the present invention is also intended to provide a multifunctional material having a good photocatalytic function by low-temperature heat treatment at 300 ° C or lower.

The multifunctional material of the present invention is formed on the surface of a substrate such as ceramics, resin, metal, wood, etc. of ceramic tiles, bathroom ceramics, glass, etc., directly or via a binder layer to form a photocatalyst layer, especially for a photocatalyst constituting the photocatalyst layer. The type of particles, the particle size, the voids formed between the photocatalyst particles, the porosity, the relationship between the bonding layer and the photocatalyst layer, the particles filled by the gaps between the photocatalyst particles, and the metal particles fixed on the surface of the photocatalyst particles are taken into consideration. The design is such that it has a photocatalytic effect of a photocatalyst layer such as deodorization, and can be a multifunctional material having excellent antibacterial properties or abrasion resistance.

<p>1Substrate</p><p>2Photocatalyst layer</p><p>3Photocatalyst particles</p><p>4Small particles</p><p>5Electronically replenished particles</p><p>6Binder layer</p>

Fig. 1(a) shows the conventional TiO₂The state before the sol is sintered, and (b) indicates the state after the gold-red ore type sintering.

Figure 2 (a) shows the conventional TiO₂The state before the particles are sintered, and (b) indicates the state after sintering.

Fig. 3 is a diagram showing the state in which the photocatalyst particles constituting the photocatalyst layer are combined by the bit energy in the multifunctional material having the photocatalytic function.

Fig. 4 is a view showing a state in which the photocatalyst particles constituting the photocatalyst layer are combined with each other in the solid phase sintering in the multifunctional material, and are represented by a pattern diagram.

Fig. 5 is a schematic view showing a state in which voids formed between photocatalyst particles constituting the photocatalyst layer are filled with small particles in the multifunctional material.

Fig. 6 is a diagram showing the state in which the surface of the photocatalyst particles of the multifunctional material shown in Fig. 3 is fixed with metal particles.

Fig. 7 is a state in which the surface of the photocatalyst particles of the multifunctional material shown in Fig. 4 is fixed with metal particles, and is represented by a pattern diagram.

Fig. 8 is a view showing a state in which the surface of the photocatalyst particles of the multifunctional material shown in Fig. 5 is fixed with metal particles, and is represented by a pattern diagram.

In the ninth embodiment, the photocatalyst layer is bonded to the substrate to form a photocatalyst layer by an adhesive, and the photocatalyst particles are combined with each other in a positional state, and are represented by a pattern.

Fig. 10 is a view showing a state in which a photocatalyst layer is bonded to a substrate by an adhesive, and photocatalyst particles constituting the photocatalyst layer are bonded to each other by solid phase sintering, and are represented by a pattern diagram.

Fig. 11 is a schematic view showing a state in which a void formed by photocatalyst layers bonded between photocatalyst particles bonded to a substrate is filled with small particles by an adhesive.

Fig. 12 is a schematic diagram showing the state in which the surface of the photocatalyst particles of the multifunctional material shown in Fig. 9 is fixed with metal particles.

Fig. 13 is a view showing a state in which the surface of the photocatalyst particles of the multifunctional material shown in Fig. 10 is fixed with metal particles, and is represented by a pattern diagram.

Fig. 14 is a view showing a state in which the surface of the photocatalyst particles of the multifunctional material shown in Fig. 11 is fixed with metal particles, and is represented by a pattern diagram.

Fig. 15 is a view showing the manufacturing method of the multifunctional material having the photocatalytic function of the present invention.

Figure 16 (a) and (b) are TiO₂An enlarged map between particles.

Figure 17 (a) ~ (c) shows TiO₂Sintering mechanism diagram of particles.

Figure 18 is a graph showing the results of an antibacterial test.

Fig. 19 is a graph comparing the results of the Cu loading test without inserting this step when the drying step was inserted before the BLB lamp was irradiated.

Fig. 20 is a graph showing the correlation between the amount of Cu carried and the amount of Cu applied.

Figure 21 is a diagram showing the manufacturing steps of another embodiment.

Figure 22 is a graph showing the results of an antibacterial test.

Fig. 23 is a graph comparing the results of the Cu loading test without inserting this step when the drying step is inserted before the BLB lamp is irradiated.

Fig. 24 is a graph showing the correlation between the amount of Cu carried and the amount of Cu applied.

Figure 25 is a graph showing the correlation between the amount of Ag carried and the survival rate of bacteria.

Figure 26 is a conceptual diagram of the basic outline when the cross-sectional direction of the multifunctional material is observed by EPMA (Electronic Line Microanalyzer).

Figure 27 is a conceptual diagram of the basic outline when the cross-sectional direction of the multifunctional material is observed by EPMA (Electronic Line Microanalyzer).

Figure 28 shows the TiO₂With SnO₂The relationship between the fit and the film strength and photoactivity.

Figure 29 is a graph showing the relationship between heat treatment temperature and photoactivity.

Figure 30 is a diagram showing the method of measuring the activity of a photocatalyst film.

Figure 31 is a view showing a method of measuring the activity of a photocatalyst film.

Figure 33 is a diagram showing the method of measuring the activity of a photocatalyst film.

Figure 33 is a graph showing the correlation between the ultraviolet irradiation time and the amount of change in pH.

Figure 34 shows R₃₀Correlation diagram with the amount of pH change.

Figure 35 shows porosity and odor resistance (R₃₀) and the correlation diagram of wear resistance.

Figure 36 shows film thickness and odor resistance (R₃₀) correlation diagram.

Figure 37 shows film thickness and odor resistance (R₃₀) and the correlation diagram of wear resistance.

Figure 38 shows SnO₂Adding amount and deodorizing property (R₃₀) and the correlation diagram of wear resistance.

Figure 39 shows SnO₂A correlation diagram between the amount added and the non-staining.

Figure 40 shows SnO₂Addition amount and TiO₂Correlation diagram of the porosity of the layer surface.

Figure 41 shows SnO₂Addition amount and TiO₂Correlation diagram of the porosity of the layer surface.

Figure 42 shows SnO₂Adding amount and deodorizing property R₃₀(L) and correlation diagram of peeling resistance.

Fig. 44 is a graph showing the correlation between the number of coatings and the non-staining property.

Figure 45 is a graph showing the relationship between the number of coatings and the wear resistance.

Figure 46 shows the number of coatings and TiO₂Correlation diagram of porosity on the surface of the layer.

Fig. 47 is a state diagram in which ultraviolet rays are irradiated and preferentially decomposed to vaporize the thermosetting resin on the photocatalyst particles to expose the photocatalyst particles to the outside air.

Fig. 48 is a view showing another embodiment similar to Fig. 47.

Fig. 49 is a view showing another embodiment similar to Fig. 47.

Fig. 50 is a state diagram in which small particles are filled between the gaps of the photocatalyst particles.

Figure 51 shows the use of rutile TiO₂Process diagram for manufacturing multifunctional materials.

Figure 52 is a graph showing the relationship between the concentration of Cu solution and the photoactivity in the case of photoreduction of a dried Cu solution.

Figure 53 is a graph showing the relationship between the concentration of Cu solution and the photoactivity in the case of photoreduction of a dry Cu solution.

Figure 54 shows the rutile TiO supported on the rutile₂Cu solution concentration and malodor removal rate R when the metal of the film is Cu₃₀Correlation diagram (the reduction of metal ions is carried out after drying the aqueous metal salt solution).

Figure 55 is a rutile TiO supported on a wall tile.₂Cu solution concentration and malodor removal rate R when the metal of the film is Cu₃₀Correlation diagram (the reduction of metal ions is carried out after drying the aqueous metal salt solution).

Figure 56 shows the formation of rutile TiO₂The firing temperature of the film and the malodor removal rate after fixing Cu₃₀Picture.

Figure 57 is a graph showing the relationship between the solution concentration of Ag and Cu and the color difference.

Figure 58 shows the porosity ratio and R₃₀And the relationship between wear resistance.

Figure 59 is a graph showing the relationship between the amount of copper carried and the survival rate of bacteria.

Fig. 60 is a graph showing the relationship between the amount of copper applied and the amount of copper supported.

Figure 61 is a graph showing the relationship between the amount of silver carried and the survival rate of bacteria.

Figure 62 is a graph showing the relationship between the amount of silver carried and the color difference.

Fig. 63 shows the effect of decolorization treatment by an aqueous solution of KI.

Figure 64 is a graph showing the change in pH of the aqueous solution of KI and the removal rate of malodor after the KI aqueous solution is decolorized.₃₀A diagram of the changes.

Figure 65 is a graph comparing the antibacterial effects.

Figure 66 is a graph showing the wear resistance of the weight ratio of cerium oxide in the film.

Figure 67 is a graph showing the photoactivity of the weight ratio of cerium oxide in the film.

Fig. 68 is a graph showing the abrasion resistance of the weight ratio of cerium oxide in the film in the comparative example.

Figure 69 is a graph showing the photoactivity of the weight ratio of cerium oxide in the film in the comparative example.

Figure 70 is a graph showing the relationship between the amount of silver carried and the survival rate of bacteria.

Hereinafter, the present invention will be described in more detail, and the following description will be made based on the drawings.

Fig. 3 to Fig. 14 show the construction of the multifunctional material having the photocatalytic function according to the present invention, which is divided into various types of presenters. The multifunctional material having the photocatalytic function of the present invention belongs to any of the constructors.

The multifunctional material shown in FIG. 3 is provided with a photocatalyst layer 2 having a photocatalytic function directly on the surface of the substrate 1, and the photocatalyst layer 2 is capable of combining the fine photocatalyst particles 3 with surface energy or curved surface energy. .

The multifunctional material shown in Fig. 4 is provided with a photocatalyst layer 2 having a photocatalytic function directly on the surface of the substrate 1, and the photocatalyst layer 2 is formed by solid phase sintering of the photocatalyst particles 3.

The multifunctional material shown in FIG. 5 is provided with a photocatalyst layer 2 having a photocatalytic function directly on the surface of the substrate 1, and the particles 4 which are smaller than the gap are filled between the photocatalyst particles 3 constituting the photocatalyst layer 2, and By the small particles 4, the photocatalyst particles 3 are combined with each other.

Moreover, in the figure, the structure in which the internal voids are filled with the particles 4 is shown, but the particles 4 may be filled in at least the gaps of the photocatalyst particles 3 in the surface layer. That is, since the mechanical strength of the photocatalyst layer attenuates the transmission of the external force when it reaches the inside, the bonding of the outermost surface is important, so that the microparticles can be filled only in the gap of the photocatalyst particles in the surface layer. However, at this time, the internal photocatalyst particles are combined by the potential energy. If the photocatalyst layer is to have sufficient strength, the average particle size of the photocatalyst particles is preferably 0.04 μm.

The photocatalyst particles 3 constituting the photocatalyst layer 2 directly formed on the surface of the multi-functional material substrate 1 shown in Fig. 6 are bonded to each other by a potential energy, and the surface of the photocatalyst particles 3 is fixed with silver, copper or cuprous oxide. Electronic particle 5.

The photocatalyst particles 3 constituting the photocatalyst layer 2 directly formed on the surface of the multi-functional material base material 1 shown in Fig. 7 are bonded to each other by solid phase sintering, and metal particles such as silver or platinum are further fixed on the surface of the photocatalyst particles 3.

The multifunctional material shown in FIG. 8 is provided with a photocatalyst layer 2 having a photocatalytic function directly on the surface of the substrate 1, and a space formed between the photocatalyst particles 3 constituting the photocatalyst layer 2 is filled with particles 4 smaller than the gap. The photocatalyst particles 3 are bonded to each other by the small particles 4, and metal particles such as silver or platinum are fixed to the surface of the photocatalyst particles 3.

The multifunctional material of FIG. 9 is provided with a photocatalyst layer 2 having a photocatalytic function on the surface of the substrate 1 through the adhesive layer 6, and the photocatalyst layer 2 is exposed to the surface layer portion while the lower layer portion is embedded in the binder. The layer 6, in addition, the surface layer is composed of fine photocatalyst particles 3 which are combined with each other in a positional energy.

The multi-functional material shown in Fig. 10 is formed by providing the photocatalyst layer 2 by the adhesive layer 6 as described above, and the surface layer photocatalyst particles 3 of the photocatalyst layer 2 are solid-phase sintered and bonded together.

The multi-functional material shown in Fig. 11 is provided with a photocatalyst layer 2 on the substrate 1 via the adhesive layer 6, and the voids formed between the photocatalyst particles 3 constituting the photocatalyst layer 2 are filled with particles smaller than the voids. The photocatalyst particles 3 are bonded to each other by the small particles 4.

The multifunctional material of Fig. 12 forms a photocatalyst layer 2 on the surface of the substrate 1 by the adhesive layer 6, and the photocatalyst particles 3 constituting the photocatalyst layer 2 are bonded to each other by the potential energy, and the surface of the photocatalyst particles 3 is further Electron-trapping particles 5 such as silver, copper or cuprous oxide are fixed.

The multifunctional material of Fig. 13 forms a photocatalyst layer 2 on the surface of the substrate 1 through the adhesive layer 6, and the photocatalyst particles 3 constituting the photocatalyst layer 2 are bonded to each other by solid phase sintering, and the surface of the photocatalyst particles 3 is further Electron-trapping particles 5 such as silver, copper or cuprous oxide are fixed.

The multi-functional material of Fig. 14 is provided with a photocatalyst layer 2 on the substrate 1 through the adhesive layer 6, and the voids formed between the photocatalyst particles 3 constituting the photocatalyst layer 2 are filled with particles 4 which are smaller than the voids. The small particles 4 bind the photocatalyst particles 3 to each other, and the surface of the photocatalyst particles 3 is further fixed with metal particles 5 such as silver or platinum.

The substrate 1 in the above materials may be any one of ceramics, resin, metal, wood or a composite thereof, such as a tile, a bathroom pottery, or a glass.

Further, the photocatalyst particles 3 have semiconductor particles which can sufficiently exhibit a band gap of a photocatalytic function such as an antibacterial function and a deodorizing function. Although the reason why the photocatalyst particles have an antibacterial property is that the voltage of the photocatalyst or more is electroacupuncated, it is generally assumed that the active oxygen is generated when the light is irradiated, and the characteristic is obtained. In order to generate active oxygen, one of the conduction bands of the semiconductor must be represented by the band mode when the hydrogen potential is generated, and the upper end of the valence band is below the oxygen generating potential. Semiconductors that can satisfy this condition have TiO₂, SrTiO₃, ZnO, SiC, gallium phosphide, CdS, CdSe, MOS₃Wait. Moreover, the position of the conduction band is moved upward after the micronization, so if it is a microparticle of about 1 to 10 nm, SnO₂, WO₃, Fe₂O₃,Bi₂O₃Etc. can also generate active oxygen. Among them, the chemically stable, inexpensive and highly active microparticles, namely anatase TiO₂optimal.

Further, the electron-trapping particles are those in which the photocatalyst is irradiated with light, and when electrons and positive holes are generated, electrons can be trapped, and electrons and positron holes can be prevented from being recombined, specifically, silver or copper. Platinum, palladium, nickel, cobalt, iron, cuprous oxide, etc.

Further, the pressure-sensitive adhesive layer 6 is made of, for example, a thermoplastic material such as glaze, inorganic glass, thermoplastic resin or solder. When the adhesive layer is formed of such a thermoplastic material, the photocatalyst can be applied to the adhesive layer at a normal temperature by a simple and inexpensive spraying method, and only the heat treatment is required, that is, the substrate 1 can be firmly adhered. The combination of the primer layer 6 and the photocatalyst layer 2 is advantageous for reducing the manufacturing cost.

In addition, the present invention relates to a multifunctional material having a photocatalytic function, and a photocatalyst layer formed by laminating or embedding a part of photocatalyst particles on a flaky layer of a thermoplastic material. The above-mentioned flaky multifunctional material can be pasted on the existing tile, bathroom pottery, building materials, etc., and can be further added with deodorant, antifouling, antibacterial, antifungal properties on the existing tile. Wait.

The average particle diameter of the photocatalyst particles 3 constituting the photocatalyst layer 2 is preferably 0.3 μm or less in order to increase the specific surface area thereof and to increase the photocatalytic activity.

The thickness of the photocatalyst layer 2 is preferably 0.1 μm to 0.9 μm. When the thickness is 0.1 μm or less, the photocatalyst particles are partially buried in the binder layer 6, and a surface on the surface of the multifunctional material which does not exhibit the activity of the catalyst is generated, so that the fungus is retained in the portion, and the antibacterial property is lowered. Further, when the thickness is 0.9 μm or more, the thickness becomes uneven, and it is difficult to remove the dirt when the stain adheres to the product. The thickness of the photocatalyst layer herein refers to a portion including the upper surface of the photocatalyst film to be buried in the underglazed layer. Specifically, an element analysis such as EPMA (Electronic Line Analyzer) is applied to obtain the composition. The value of the main component of the glazed layer is increased, and the distance from the uppermost layer to the outermost surface of a certain portion is measured.

Moreover, changing the thickness of the photocatalyst layer 2 can also achieve the effect of mounting on the crucible, that is, when the thickness is 0.2 μm or more and 0.4 μm or less, the rainbow color pattern can be caused by the interference of light on the film thickness portion of the photocatalyst layer. When it is only intended to form a base color, a pattern or a combination of the two in appearance, it is possible to produce a photocatalytic film thickness of 0.1 μm to 0.2 μm or 0.4 μm to 1 μm excluding the portion affected by the light interference. According to this method, it can be widely applied to tiles, washstands, baths, toilets, flow tables, conditioning stations, and the like.

When only the photocatalyst particles 3 are bonded to each other, only the mutual energy (adsorption) or sintering between the photocatalyst particles can be relied upon. However, when photocatalytic particles are to be sintered to each other, they must be sintered at a relatively high temperature. On the other hand, when adsorbed, the specific surface area of the photocatalyst particles must be increased to a considerable extent, and the filling property needs to be improved. Otherwise, it cannot be fully combined, and only photocatalyst is consumed for manufacturing. When the active site of the particles is adsorbed, the method is limited when the multifunctional material having sufficient catalyst activity and abrasion resistance is used.

Further, in order to strengthen the combination of the photocatalyst particles 3, when particles having a larger gap than the photocatalyst particles 3 are used, not only a sufficient bonding force but also a part of the photocatalyst particles exposed on the surface of the multifunctional material are covered, and more The surface of the functional material generates a part that does not exert the activity of the catalyst, so that the fungus is retained in the part, and the antibacterial property is remarkably lowered.

Further, the space between the photocatalyst particles referred to herein is the neck of the photocatalyst particles 3 and 3 shown in Fig. 16(a), and the gap between the photocatalyst particles 3 and 3 as shown in Fig. 16(b). Both. Therefore, the particles 4 having a smaller particle diameter than the photocatalyst particles are referred to as the particles between the particles and the photocatalyst particles, and any smaller portion of the gap between the photocatalyst particles. Fig. 16(b) is the most effective means for combining photocatalyst particles with each other.

The small particles 4 filled in the voids of the photocatalyst particles 3 are basically not subject to the material, but it is preferably a good adsorption force. Materials with extremely poor adsorption capacity cannot achieve the purpose of combining photocatalyst particles with each other. Moreover, materials with excessive adsorption capacity will have a great chance of covering the surface activity of photocatalyst particles before being inserted into the void. From this point of view, the material filled in the voids of the photocatalyst particles is preferably a metal such as tin, titanium, silver, copper, zinc, iron, platinum, cobalt, palladium or nickel or an oxide thereof. In the past, zeolite, activated carbon, clay, and the like which are used as an adsorption carrier are suitable. Among the above metals or oxides, cerium oxide is most suitable for those having a moderate adsorption capacity. In addition, metals such as silver and copper or oxides thereof can combine photocatalyst particles with each other, and have unique antibacterial properties and odor resistance. Therefore, in the use of this function, there is an auxiliary photocatalyst when the light is not irradiated. The role, so it is very suitable. In other words, the metal particles 5 may be used as the small particles 4 filled in the voids of the photocatalyst particles 3.

Further, the average particle diameter of the particles 4 filled in the voids of the photocatalyst particles 3 is preferably 4/5 or less on average, and the average particle diameter of the photocatalyst particles 3 is preferably.

The particles 4 embedded in the voids of the photocatalyst particles 3 not only enter the space between the photocatalyst particles but also adhere to the photocatalyst particles when the current manufacturing method is employed. When the particle diameter of the buried void is greater than 4/5 of the average particle diameter of the photocatalyst particles, the probability of adhesion to the surface of the photocatalyst particles is higher than that of the photocatalyst particles, and the bonding strength between the photocatalyst particles 3 is lowered. Moreover, when the particles buried in the gap are larger than the photocatalyst particles, a part of the photocatalyst particles are covered, and the surface of the multifunctional material is not able to exert the activity of the catalyst, and in this part, the fungus is retained, especially Significantly reduce the antibacterial properties.

Further, when the average particle diameter of the particles filled in the voids of the photocatalyst particles 3 is 0.01 μm or less, the specific surface area can be increased, and an appropriate adsorption force can be obtained, which is most preferable.

Further, the total amount of the particles 4 filled in the voids of the photocatalyst particles 3 is preferably 10% to 60% in terms of the molar ratio of the photocatalyst particles 3 and the filler particles 4. When the photocatalyst particles are heat-treated at a temperature range in which the photocatalyst particles are not sintered, when the photocatalyst layer is fixed to the substrate by an adhesive, if the amount of particles buried in the void is too small, the photocatalyst particles cannot be firmly bonded, and on the other hand, buried. When the amount of particles in the voids is too large, a portion which does not exhibit catalyst activity is formed on the surface of the multifunctional substrate, and the bacteria are retained in the portion, and the antibacterial property is remarkably lowered. Therefore, the above range is preferable.

Further, the particles 4 which are filled in the gaps of the photocatalyst particles 3 are preferably selected such that the vapor pressure is higher than the material constituting the photocatalyst particles, and the particles in the neck of the photocatalyst particles are uniformly filled in the voids of the photocatalyst particles. Because the photocatalyst particles are to be firmly bonded to each other to increase the peel strength of the photocatalyst layer, not only the filling but also the sintering method is preferred. When the material having a high vapor pressure as described above is selected as the particles 4 embedded in the void, not only the sintering aid but also the sintering temperature can be lowered.

The above-mentioned substances having a high vapor pressure include tin oxide, antimony oxide, zinc oxide, etc., but it is safe to say that tin oxide is preferred.

Further, the layer containing the particles 4 filled in the voids of the photocatalyst particles 3 preferably has a thickness of 0.1 μm or more, and when the layer thickness is 0.1 μm or less, the photocatalyst particles (and the voids may be buried depending on the method of production). The particles are partially embedded in the adhesive layer 6, and a part of the surface of the multifunctional material which does not exhibit the activity of the catalyst is formed, and the residual fungus is remarkably reduced in the portion. The thickness of the layer in which the particles filled with the voids of the photocatalyst particles are referred to herein is the thickness of the uppermost layer to the portion where the lower layer of the adhesive is buried, and the thickness after the unevenness is averaged.

Fig. 15 is a view showing an example of a method for producing a multifunctional material having a photocatalytic function according to the present invention. In the present invention, first, as shown in Fig. 15(a), a substrate 1 is prepared, as shown in the figure (b). The surface of the material 1 forms an adhesive layer 6. The adhesive layer 6 is selected from materials having a softening temperature lower than that of the substrate 1. For example, when the substrate 1 is a tile, a crucible or a ceramic, the adhesive layer 6 is a glaze layer or a printing layer is directly used.

Then, as shown in the figure (c), a photocatalyst layer 2 made of photocatalyst particles such as TiO particles is formed on the adhesive layer 6. At this time, the photocatalyst layer 2 is placed thereon with a bonding force to the extent that it does not fall off from the adhesive layer 6 when it is fired.

Or, before the adhesive layer 6 is formed on the surface of the substrate 1, the photocatalyst layer 2 is formed on the adhesive layer 6 as shown in (b'), and the adhesive layer 6 is placed on the substrate 1.

Then, the heat treatment is performed at an atmosphere temperature higher than the softening temperature of the adhesive layer by 20 ° C or more and 320 ° C or less and lower than the softening temperature of the substrate 1 , that is, as shown in the figure (d) or the ninth to fourteenth In the photocatalyst layer 2, a portion of the layer below the adhesive layer is deposited on the adhesive layer to solidify the adhesive layer, and a part of the adhesive layer is buried in the adhesive layer and is firmly held. In it. Further, the photocatalyst particles 3 constituting the surface layer of the photocatalyst layer 2 which are in contact with the external air are sintered by the potential energy, the intermolecular force or the burning, and are partially combined as in the case of Fig. 16 (a), and the other portions are as shown in the 16th. Figure (b) is the same as detachment. That is, the surface of the photocatalyst particles in the surface layer is substantially exposed to the outside.

Here, the heat treatment temperature is higher than the softening temperature of the adhesive layer 6 by 20° C. or more and 320° C. or less. It is necessary to take a long time to soften the adhesive layer at 20° C. or less, and the photocatalyst particles 3 cannot be sufficiently held. On the other hand, if it is 320 ° C or more, the adhesive layer will rapidly melt, the photocatalyst particles will be buried in the adhesive layer, or the convex and concave surfaces will be formed, and even a fault or pinhole will occur, so the optimum system is 40 ° C or more. Below °C.

Further, when the specific gravity of the photocatalyst particles 3 is δt and the specific gravity of the adhesive layer 6 is δb, it is preferably 0 δt - δb 3, preferably 0.5 δt - δb 2.0. When the difference in specific gravity between the photocatalyst particles and the adhesive layer is too small, when the adhesive layer is melted, the photocatalytic particles move at a slow rate in the vertical direction in the adhesive layer, and the photocatalyst particles after firing are easily peeled off. When the difference in specific gravity between the photocatalyst particles and the adhesive layer is too large, the photocatalyst particles are increased in the vertical direction. The photocatalyst particles are almost completely embedded in the adhesive layer, and when this happens locally, the bacteria are retained at the bottom, and the antibacterial is lowered. Sex.

In addition, if another application method of the method requires δt-δb&gt;3.0, another second adhesive layer of 0δt-δb3.0 may be disposed between the adhesive layer and the photocatalyst particles for remediation.

Further, when δt - δb &lt; 0, it is possible to pressurize at the time of heat treatment, that is, to increase the specific gravity difference δt - δb. Therefore, by the HIP treatment and the hot extrusion treatment, the same effect at 0 δt - δb 3.0 can be obtained.

Further, the photocatalyst particle voids constituting the exposed portion of the self-adhesive layer 6 are specifically between the neck of the photocatalyst particle 3b shown in Fig. 16(a) or the photocatalyst particle 3 shown in Fig. 16(b). In order to bond the photocatalyst particles to each other, particles 4 (Sn, Ti, An, Cu, Zn, Fe, Pt, CO, Pd, Ni, etc., metals or oxides, etc.) having a smaller particle size than the voids may be filled.

Further, another method for producing the multifunctional material having the photocatalytic function of the present invention can form an adhesive layer 6 of a thermoplastic material on a substrate 1 such as ceramic, resin or metal, in which the adhesive layer 6 is formed. a mixture of photocatalyst particles 3 mixed with particles having a small particle diameter in a state of being coated with a sol or a state of a light substance to form a photocatalyst layer 2, and then softening the above-mentioned adhesive layer 6, embedding a portion of the photocatalyst layer 2 under the layer The adhesive layer 6 is then cured.

According to this method, it is extremely simple, since the mixture of the particles 4 embedded in the voids and the photocatalyst particles can be mixed in a sol state or a precursor state to form a photocatalyst layer, so that the photocatalyst particles 3 and the buried void can be conveniently controlled. The mixing ratio between the particles 4.

Another method for producing the multifunctional material having the photocatalytic function of the present invention can be coated on the sheet adhesive layer 6 made of a thermoplastic material, and the photocatalyst particles 3 and the particles having a small particle size are mixed in a sol or photochromic state. The resulting mixture is formed into a photocatalyst layer 2, and the sheet-like adhesive layer 6 forming the photocatalyst layer is placed or attached to a substrate such as ceramic, resin or metal, and then the adhesive layer is softened, and the photocatalyst layer is buried. A portion of the lower layer is in the adhesive layer and is then cured.

Further, another method for producing the multifunctional material having the photocatalytic function of the present invention can form an adhesive layer 6 of a thermoplastic material on a substrate 1 such as ceramic, resin or metal, and then an adhesive layer thereon. 6 is formed on the photocatalyst layer 2 to form the photocatalyst layer 2, and then softens the adhesive layer 6, and a part of the photocatalyst layer 2 is buried in the adhesive layer 6, and then solidified, and then coated with small particles having the above particle diameter. The solution is applied to the photocatalyst layer to fix the small particle size 4 of the particle size to the photocatalyst particles via heat treatment.

When the particles embedded in the voids are oxides, the method is extremely convenient and easy to implement, and when a relatively porous photocatalyst layer is formed, a large amount of particles embedded in the voids can be attached.

Another method for producing the multifunctional material having the photocatalytic function of the present invention can form the photocatalyst layer 2 formed by the photocatalyst particles 3 on the sheet-like adhesive layer 6 of the thermoplastic material, and then form the photocatalyst layer into a flaky paste. The primer layer 6 is placed or adhered to a substrate 1 such as ceramic, resin or metal, and then the adhesive layer is softened, and a portion of the photocatalyst layer is buried under the adhesive layer, followed by curing, and then coating. The solution containing the metal particles 4 is applied to the photocatalyst layer via the heat treatment to fix the particles having the small particle diameter to the photocatalyst particles 3.

Further, another method for producing the multifunctional material having the photocatalytic function of the present invention can form an adhesive layer 6 of a thermoplastic material on a substrate 1 such as ceramic, resin or metal, in which the adhesive layer 6 is formed. The photocatalyst layer 2 is formed by forming the photocatalyst particles 3, and then the adhesive layer 6 is softened, and a portion of the photocatalyst layer 2 is buried in the adhesive layer, and then the adhesive layer is cured, and then the small metal particles are contained. The ionic solution of 4 is applied to the photocatalyst layer, and then the light containing ultraviolet rays is irradiated to reduce the metal ions to fix the photocatalyst particles.

In this method, if the particles buried in the void are metal, it is simpler and easier to implement, and the metal can be fixed in a very short time (minutes). Further, the lamp used for ultraviolet irradiation may be any one of an ultraviolet lamp, a BLB lamp, a xenon lamp, a mercury lamp, and a fluorescent lamp.

Another method for producing the multifunctional material having the photocatalytic function of the present invention can form the photocatalyst layer 2 formed by the photocatalyst particles 3 on the sheet adhesive layer 6 formed of the thermoplastic material, thereby forming a sheet-like adhesion of the photocatalyst layer. The agent layer 6 is placed or adhered to a substrate such as ceramic, resin or metal, and then the layer of the adhesive is softened, a portion of the photocatalyst layer is buried under the adhesive layer, and then the adhesive layer is cured, and then The ionic solution containing the small metal particles 4 is applied to the photocatalyst layer 2, and then irradiated with ultraviolet rays to reduce the metal ions to fix the photocatalyst particles.

Further, in another method for producing a multifunctional material having a photocatalytic function, the adhesive layer 6 formed of a thermoplastic material can be formed on the substrate 1 such as ceramic, resin or metal, and then formed on the adhesive layer 6. The photocatalyst layer 3 is formed into a photocatalyst layer 2, and an ionic solution containing the small particle metal particles 4 is applied onto the photocatalyst layer 2, and then light rays containing ultraviolet rays are irradiated to reduce metal ions, and the photocatalyst particles 3 are immobilized. The adhesive 6 is softened so that a portion of the photocatalyst layer is buried in the adhesive layer, which in turn cures the adhesive layer.

According to this method, the heating process step can be completed at one time to improve the production efficiency.

Further, in another method for producing a multifunctional material having a photocatalytic function according to the present invention, a photocatalyst layer 2 formed by photocatalyst particles 3 is formed on a sheet-like adhesive layer formed of a thermoplastic material, and the photocatalyst layer 2 is coated with particles. The ionic solution of the metal particles 4 having a small diameter is then irradiated with light containing ultraviolet rays to reduce metal ions, the photocatalyst particles 3 are immobilized, and the sheet-like adhesive layer forming the photocatalyst layer 2 is placed or attached to the ceramic, and the resin On the substrate 1 such as a metal, the adhesive layer 6 is then softened, and a portion of the lower layer of the photocatalyst layer 2 is buried in the adhesive layer, followed by curing of the adhesive layer.

Here, ZnO may be used as the photocatalyst particles, and the metal particles 4 filled in the voids of the photocatalyst particles may be silver or silver oxide. Ag or silver oxide particles can not only strengthen the photocatalyst ZnO particles, but also enhance the photocatalytic effect of ZnO, and it also has antibacterial and deodorizing effects. Moreover, when ZnO is selected as the photocatalyst, the problem of coloring due to silver ions can be solved, and the base color of the substrate can be selected, patterned or combined to further enhance the decorative effect.

Further, a solution containing a salt of a colorless or white salt which is insoluble in metal ions filled in the voids of the photocatalyst particles is brought into contact with the photocatalyst layer, and then light such as ultraviolet rays may be irradiated.

At this time, it is possible to solve the coloring problem of the particles buried in the void without relying on the combination of ZnO and Ag or AgO, and also to select the base color of the substrate, the pattern or a combination of the two to improve the decorative effect.

Also, TiO can be used.₂In the photocatalyst particles 3, the heat treatment temperature of the softening adhesive layer 6 is 800 ° C or more and 1000 ° C or less. When using 800 ° C or higher, it can be used in TiO through initial sintering.₂The neck is formed between the particles, which can increase TiO₂Bonding strength between particles, but above 1000 °C, it proceeds to the mid-sinter sintering process due to TiO₂The solid phase sintering causes the photocatalyst layer to shrink in volume and is highly susceptible to cracking.

Again, with TiO₂For the photocatalyst particles, Ag is used as the particles 4 filled in the gaps of the photocatalyst particles, and the salt solution containing the colorless or white salt which can form insoluble ions with the Ag ions may be KI, KC.<img file="TW406031B_D0001.tif" />, FeC<img file="TW406031B_D0002.tif" />An aqueous solution of an equal halide. AgI and AgC are formed between the Ag system and the halogenated base<img file="TW406031B_D0003.tif" />It is insoluble and has no color or white salt, so it can be combined with the base color, pattern or combination of the substrate to improve the decorative effect.

Further, before the step of applying the photocatalyst particles on the adhesive layer, if it is desired to have a dispersion step, the dispersion step may be dispersed as a sol of the photocatalyst particles or a dispersant in the solution in the solution, preferably using a ratio The heat treatment temperature of the softening adhesive layer can be vaporized at a lower temperature.

In the prior art, there is no sufficient deodorant property below 320 ° C because of the adhesion to TiO in the dispersion step.₂The dispersant on the surface of the particle is not fully vaporized and remains without evaporation, making TiO₂The surface of the particle is not sufficiently exposed to the uppermost surface of the substrate, and the photocatalytic function cannot be sufficiently exhibited. Further, the dispersing agent which can be vaporized at a low temperature is preferably an organic dispersing agent having a molecular weight of 10,000 or less, and a phosphate dispersing agent.

Specific embodiments are given below.

Example 1

Forming SiO on the surface of a 150 square ceramic tile substrate by spraying₂-A<img file="TW406031B_D0004.tif" />O₃-Na/K₂The binder layer formed by the O glass material is dried and then coated with 15% TiO by spraying.₂Aqueous sol solution to form TiO with a film thickness of 0.8 μm₂Layer, and then in each of the rolling kiln, heat-fired the laminated binder layer and TiO at different atmosphere temperatures₂After the substrate is formed, the solidified functional material is cooled and solidified.

TiO as referred to herein₂The aqueous sol solution refers to hydrolyzing TiC under hydrothermal conditions in the range of 100-200 ° C in an autoclave.<img file="TW406031B_D0005.tif" />Obtain anatase TiO with a crystallite diameter of 0.007~0.2μm₂The ore is dispersed in the sol state in a number of % to tens of % in an acidic aqueous solution such as nitric acid or hydrochloric acid or an alkaline aqueous solution such as ammonia, and an organic solution of triethylamine and trimethylolamine in a range of 0.5% or less is added for the purpose of improving dispersibility. The acid salt, isovaleryl alcohol, trimethylolpropane, etc. are used as surface treatment agents. Also, TiO₂The particle size of the sol was processed by a painter observed by SEM, and the crystal grain size was calculated from the integral width of the powder X-ray diffraction.

Further, the coating method is a method of applying spray, but the same results can be obtained by the dip coating method or the spin coating method.

Antibacterial and anti-wear properties are evaluated for the multifunctional materials.

The bactericidal effect of the antibacterial strain test on Escherichia Coli W3110 strain. Drop the bacterial liquid 0.15m on the uppermost surface of the multifunctional material sterilized with 70% ethanol in advance.<img file="TW406031B_D0006.tif" />(1~5×10⁴CFU), a glass plate (10 × 10 cm) was placed to adhere to the uppermost surface of the substrate as a sample. After illuminating the white light for 30 minutes (3,500 candelas), the sterilized gauze was used to wipe the irradiated sample and the sample liquid held under the light-shielding condition, and recovered in 10 m.<img file="TW406031B_D0007.tif" />In the physiological saline solution, the survival rate of the bacteria was determined as an evaluation index.

The abrasion resistance is made by sliding the rubber with a plastic wiping rubber, and the appearance is evaluated.

Table 1 below shows the use of ceramic tiles as a substrate, using SiO₂-A<img file="TW406031B_D0008.tif" />O₃-Na/K₂When the O glass material is used as a binder, the change in the antibacterial property due to the sintering temperature is changed.

<tables><img file="TW406031B_D0009.tif" /></tables>+++: The survival rate of coliform is below 10%

++: Survival rate of coliforms is 10% or more and 30% or less

+: The survival rate of coliform is 30% or more and 70% or less

-: Survival rate of coliforms is over 70%

: After 40 round trips, the damage did not occur.

: Damage occurred after 10-40 sliding, photocatalyst layer (TiO₂Membrane)

: Initiation of damage by 5-10 sliding, photocatalyst layer (TiO₂Membrane)

×: visible damage after 5 times of sliding, photocatalyst layer (TiO₂Membrane)

SiO used as a binder here₂-A<img file="TW406031B_D0010.tif" />O₃-Na/K₂The O glass had a specific gravity of 2.4, a film thickness of 200 μm at the time of coating, and a softening temperature of 680 °C. Also, the TiO obtained in Table 1₂The NO.1~3 are anatase type, the specific gravity is 3.9, the NO.4.5 is rutile type, and the specific gravity is 4.2.

In Table 1, the firing temperature of NO.1 is only 20 °C higher than the softening temperature of the binder, and the viscosity of the binder cannot be sufficiently reduced, so the anatase TiO which constitutes the lowermost layer of the photocatalyst layer is formed.₂It is not possible to fully embed the adhesive layer, and for this reason, it is peeled off only by sliding 5 to 10 times in the abrasion resistance test. In addition, the antibacterial property is due to the use of anatase with excellent photocatalytic activity, and TiO-DTA observation of TiO at 300 ° C or higher.₂The organic components of the sol have almost been decomposed, gasified, and attached to TiO.₂The dispersing agent such as the surface treatment agent on the surface should be vaporized, and the firing temperature is again 700 ° C, so the processing temperature is quite high and the excellent value of ++ is obtained.

The NO.3~5 series firing temperature is 800°C or more and 1000°C or less. In terms of durability, it is possible to withstand 40 or more round-trip sliding tests without being changed to excellent. The reason should be the surface TiO₂The particles form a neck after initial firing. Moreover, when treated at 1100 ° C, the TiO on the surface of the multifunctional material was removed from the rolling kiln after cooling and solidification.₂The layer has cracked. This is determined by TMA.₂Judging from the test piece, knowing the TiO₂A medium-term sintering generator that particleizes significant volume shrinkage.

The antibacterial properties of NO.4 and NO.5 are poor, and two reasons can be guessed.₂The particles have been phase-transferred to rutile, and the other is that the firing temperature is 300 ° C higher than the softening temperature of the binder, and the viscosity of the binder becomes too low to form the TiO of the photocatalyst layer.₂The particles are buried in the binder layer. Here TiO₂The phase transfer of particles to the rutile type is not the cause. Rutile TiO₂Although anatase TiO₂Slightly poor, but still has some photocatalytic activity. For example, spraying TiO directly₂The sol was fired on a porous alumina substrate, and the sample which was cooled and solidified at 950 ° C was still antibacterial. Therefore, it can be seen that the firing temperature is higher than the softening temperature of the binder by 300 ° C, the viscosity of the binder is too low, and the TiO which constitutes the photocatalyst layer₂The fact that the particles are buried in the binder layer is also a cause.

Further, when Ti and Si (adhesive main component) in the cross-sectional direction of the sample were analyzed by elements such as EPMA, a mixed layer of Ti and Si was observed, and TiO of the photocatalyst particles was confirmed.₂Has been buried in it.

From the above embodiment 1, that is, at least the photocatalyst is TiO₂, the binder layer is SiO₂-A<img file="TW406031B_D0011.tif" />O₃-Na/K₂The following facts can be confirmed when O glass.

1 The firing temperature is 20 ° C higher than the softening temperature of the binder. When the multifunctional material is produced at a temperature higher than 300 ° C, the antibacterial property and the abrasion resistance are good. The reason for this is that the viscosity of the binder has been adjusted to be suitable for embedding TiO in the binder layer.₂The value is due to.

The 21 multifunctional materials were confirmed to be TiO₂The particles have been embedded in the adhesive layer.

3 When the firing temperature is 800 ° C or more and 1000 ° C or less, the abrasion resistance is not changed after 40 or more sliding tests, and the abrasion resistance is excellent, and it is supposed to be TiO.₂The neck is formed between the particles and is firmly bonded.

Example 2

Formation of SiO by spray coating on a surface of 100×100×5 alumina substrate (96% alumina density)₂-A<img file="TW406031B_D0012.tif" />O₃-Adhesive layer of PbO glass, after drying, coating 15% TiO by spraying₂Aqueous sol solution to form TiO with a film thickness of 0.8 μm₂Layer, and then in each of the rolling kiln, heat-fired the laminated binder layer and TiO at different atmosphere temperatures₂After the substrate is formed, the solidified functional material is cooled and solidified.

The following is shown in Table 2, using alumina as a substrate, using SiO₂-A<img file="TW406031B_D0013.tif" />O₃-PbO glass as a binder, which causes an antibacterial property and a change in abrasion resistance when the firing temperature is changed.

<tables><img file="TW406031B_D0014.tif" /></tables>

The SiO of the binder used here₂-A<img file="TW406031B_D0015.tif" />O₃The softening temperature of the -PbO glass material is 3.8 ° C in a specific gravity of 3.8, and the film thickness at the time of coating is 150 μm. Also, the obtained TiO₂The crystal forms are all anatase.

In the abrasion resistance test of Table 2, NO.6 was peeled off by slipping after 10 times or less, but NO.7,8 would not be damaged if it slipped 10 times or more, and NO.9, NO.10 would slide 40 times. The above will not be damaged.

NO.9,10 shall not be damaged when sliding more than 40 times. The firing temperature shall be 800 °C or higher, in TiO.₂Neck formation between particles, TiO₂The particles are firmly bonded to each other.

NO.7 is damaged or peeled after sliding 10 times or less. This is because the firing temperature is 20 °C higher than the softening temperature of the binder. The viscosity of the binder cannot be sufficiently reduced, and the anatase of the lowermost layer of the photocatalyst layer is formed. Mineral TiO₂The particles cannot be sufficiently buried in the adhesive layer.

In contrast, NO.7,8 will not be damaged if it is slid more than 10 times. This should be the difference between the firing temperature and the softening temperature of the adhesive, although the temperature of the neck is not reached, and the bond can be adjusted. The viscosity of the agent is TiO₂It can be caused by the value embedded in the adhesive moderately.

On the other hand, in the antibacterial test of Table 2, NO.6~NO.9 can obtain good results of +++ or ++, but NO.10 is only +. This is because the firing temperature is 320 ° C higher than the binder softening temperature, the viscosity of the binder is too low, and the TiO which constitutes the photocatalyst layer₂The particles are embedded in the adhesive layer.

Example 3

Melt cooling solidified SiO in the model₂-A<img file="TW406031B_D0016.tif" />O₃-BaO glass was added to work as a 100 × 100 × 1 glass flake, and 15% TiO was coated thereon by spraying.₂Aqueous sol solution (same as in Example 1) to form TiO having a film thickness of 0.8 μm₂Floor. Then, the glass flakes were placed on an alumina substrate (100×100×5), and the atmosphere temperature was changed in each of the examples of the Silicon liquid furnace, and after heating and firing, the more functional material was cooled and solidified.

Table 3 below shows changes in antibacterial property and abrasion resistance when the firing temperature of the above-described multifunctional material is changed.

<tables><img file="TW406031B_D0017.tif" /></tables>

SiO used here₂-A<img file="TW406031B_D0018.tif" />O₃The softening temperature of the binder of -BaO glass is 620 ° C, the specific gravity is 2.8, and the TiO on the multifunctional material₂The crystal type NO. 11 to 13 is anatase type, and the NO. 14 type is rutile type.

In the abrasion resistance test of Table 3, the NO.11 system was damaged by slipping 10 times or less, and it was peeled off, and the NO.12 system was not damaged 10 times or more, and NO.13,14 did not slide even 40 times or more. It is damaged and has excellent results.

NO.13,14 which is not damaged by sliding more than 40 times, the firing temperature is above 800 °C, TiO₂Neck formation between particles, TiO₂The particles are firmly bonded to each other.

If the sliding is less than 10 times, it will be damaged. The peeling NO.11 is only because the firing temperature is only 20 °C higher than the softening temperature of the binder. The viscosity of the binder cannot be sufficiently reduced to form the anatase TiO of the lowermost layer of the photocatalyst layer.₂The particles are not fully buried in the binder.

In contrast, NO.12 has not been damaged after more than 10 times of sliding. This is because the temperature does not reach the temperature of the neck, but the difference between the firing temperature and the softening temperature of the binder can adjust the binder. Stickiness to moderately bury TiO₂Due to the value in the adhesive layer.

On the other hand, in the antibacterial test of Table 3, NO. 11 to 13 series +++ or ++ had excellent effects, but NO. 14 was one. This system is due to TiO₂Will become rutile type, the firing temperature is 320 ° C higher than the softening temperature of the binder, the viscosity of the binder is too low, and the TiO which constitutes the photocatalyst layer₂Two reasons for the particles being buried in the binder.

From the above, it is known that TiO is coated in advance in the binder.₂After the particles are adhered to the substrate and fired into a multi-functional material, the binder may be coated on the surface of the substrate, and then coated with TiO.₂Particles give excellent results in the same way as more functional materials.

Example 4

Applying an acrylic resin binder to the surface of a 100×100×5 polyimine-based resin substrate, and applying 15% TiO by spray coating₂Aqueous sol solution to form a TiO of 0.8 μm film thickness₂a layer, followed by firing a laminated binder layer and TiO at 150 ° C in a nichrome furnace₂The substrate of the layer, a much more functional material.

Table 4 below shows the effect on the antibacterial property and the abrasion resistance when the firing temperature of the above multifunctional material is changed.

<tables><img file="TW406031B_D0019.tif" /></tables>

Again, 15% TiO in Table 4₂The sol aqueous solution was changed by the following method.

NO.15: directly use 15% TiO used in Example 1.₂Aqueous sol solution.

NO.16: Hydrolysis of TiC at 110~150 °C in a hot pressure cooker<img file="TW406031B_D0020.tif" />After the aqueous solution, the nitric acid-adjusted product was adjusted to pH 0.8, and the surface modifier was not used to disperse it, and then the aggregate was removed. Immediately after spraying, the aggregates are removed.

Here TiO₂The specific gravity is 3.9, the crystalline type is anatase, and the acrylic resin has a specific gravity of 0.9, which can be 70 ° C depending on the viscosity of the softening point of the glass.

In terms of wear resistance, NO.15 and NO.16 can be slid 10 times or more without damage. This is because the difference between the firing temperature and the softening temperature of the binder can adjust the viscosity of the binder to TiO.₂It can be caused by the value embedded in the binder.

On the other hand, in the antibacterial test, although NO. 15 is one, NO. 16 is ++, and this means that a multifunctional material having antibacterial properties can be produced at 30 ° C or lower. According to DTA-TG, this different antibacterial factor is due to the TiO in NO.15.₂The sol system can be decomposed at 200~350 °C, and the component of evaporation, that is, NO.16, is not seen. It can be seen whether or not organic components cover the TiO.₂It is the difference in its antibacterial properties.

Moreover, the difference in specific gravity between the anatase and the acrylic resin is 3, and as long as the difference is such, the TiO which constitutes the photocatalyst layer₂The particles were not buried in the binder layer, and it was confirmed that the particles had good antibacterial properties.

Example 5

On the surface of 100×100×5 alumina substrate, the binder layer was formed by spraying method with different proportions of glass, respectively, and then sprayed with 15% TiO.₂The sol aqueous solution forms a TiO of 0.8 μm film thickness₂The layer is then heated and fired in a rolling kiln at a temperature of 750 ° C to form a laminated layer and TiO₂The resulting substrate cools and cures the more functional material.

Table 5 below shows the effect of changing the firing temperature of the above-mentioned multifunctional material on the antibacterial property and the abrasion resistance.

<tables><img file="TW406031B_D0021.tif" /></tables>

In the antibacterial test, NO.17~NO.20 had excellent +++ results. The baking temperature is higher than the softening temperature of the binder by 30 ° C or more and 300 ° C or less. The difference between the firing temperature and the softening temperature of the binder can be adjusted to adjust the viscosity of the binder to moderately TiO.₂This result is obtained by embedding the value in the binder.

In the abrasion resistance, the NO. 17 is slipped 5 times or less, that is, it is damaged and peeled off, but NO. 18 to 20 are not damaged even if it is slid 10 times or more.

According to the investigation, the reason should be that NO.17 is different from the others, and the specific gravity of the binder is higher than that of TiO.₂The ratio is large, so the anatase TiO which constitutes the lowermost layer of the photocatalyst layer₂The particles are not sufficiently buried in the binder layer.

Therefore, it is known that the wear resistance of multifunctional materials is also affected by TiO.₂The specific gravity of the adhesive and the binder have a higher specific gravity than the TiO₂It also causes poor wear resistance when the ratio is large.

Example 6

Forming SiO on the surface of 150 square tile substrate₂-A<img file="TW406031B_D0022.tif" />O₃-BaO glass (softening temperature 620 ° C) into a binder layer, sprayed with TiO₂Sol and SnO₂The stirred aqueous solution of the sol was fired at 750 ° C, cooled, and the functionally more material was cured.

Also, TiO₂Sol concentration is 4-6 wt%, with NH₃The aqueous solution was adjusted to pH 11, TiO₂The crystallite size of the particles is 0.01 μm, SnO₂The crystallite size of the particles was 0.0035 μm.

In Table 6, the multifunctional material prepared as described above is shown to be changed to TiO.₂Particles and SnO₂Total amount of SnO₂The effect of the amount (Morby) on the antibacterial property and the abrasion resistance is shown in the table.

<tables><img file="TW406031B_D0023.tif" /></tables>

Resistance to wear, with SnO₂The increase in the amount can improve the wear resistance. When 10% or more is added, it will not be damaged or changed without sliding for 40 times.

In the antibacterial test, the range of up to 20% or more may be ++ when it is +++ to 60% as in the case of no addition, but when the weight is increased, the surface of the unit substrate is TiO.₂The probability of particles is greatly increased, and the antibacterial property is deteriorated, and at 100%, it is -.

So SnO₂The amount added is in the case of Moby, in TiO₂With SnO₂A multifunctional material having an antibacterial property and an excellent abrasion resistance can be provided in an amount of 10% or more and 60% or less, preferably 10% or more and 20% or less.

SnO₂An increase in the amount of wear can improve the wear resistance according to the author of the following. That is, SnO at a high temperature of 600 ° C or higher₂Compared with TiO₂The vapor pressure is high, TiO before sintering₂The interval between the particles 3b is as shown in Fig. 17(a).₀But TiO with a positive curvature surface₂The surface of the particle 3 has a high vapor pressure, while the surface with a negative curvature, that is, two TiO₂The surface of the neck where the particles 3b are butted has a low vapor pressure. As a result, as shown in Figure 17 (b), the neck system has a higher vapor pressure than TiO.₂SnO₂Therefore, as shown in Fig. 17 (c), the sintering is performed by a gasification-condensation mechanism.

And after sintering by a gasification-condensation mechanism, the sintered TiO₂Particle spacing L₂The interval between the system and the sintering₀They are about equal, so cracks and the like do not occur.

As described above, the binder is retained on the surface of the substrate with TiO₂In the composite of the particle layer, the TiO exposed on the outermost surface₂Interstitial void filling of SnO₂When the particles are fired at 600 ° C or higher, cracking does not occur, and TiO is bonded.₂The neck between the particles improves the wear resistance.

Comparative Example 7

As in Example 6, SiO was formed on the surface of a 150 square tile substrate.₂-A<img file="TW406031B_D0024.tif" />O₃-BaO glass (softening temperature 620 ° C) into a binder layer, sprayed with TiO on it₂Sol and SnO₂The stirred aqueous solution of the sol was fired at 750 ° C, cooled, and the functionally more material was cured.

Also, TiO₂The particle sol concentration is 4-6 wt%, with NH₃The aqueous solution was adjusted to a pH of 11, and the crystallite size was 0.01 μm as in Example 6, SnO.₂The crystallite size of the particles used was a larger 0.008 μm.

The antibacterial test and the abrasion resistance test were carried out for the multifunctional material produced as described above, and the results of comparison with Example 6 are shown in Table 7 below.

<tables><img file="TW406031B_D0025.tif" /></tables>

As a result, a SnO of 0.008 μm was known.₂The effect of particles on improving wear resistance is compared to the use of SnO at 0.0035 μm.₂Particles are weak, on TiO₂With SnO₂When the combined molar ratio is more than 60%, it can be achieved by sliding 40 times without damage and changing.

In the antibacterial test, using SnO of 0.0035μm₂In the case of particles, the range of 20% or more can still be +++ as in the case of no addition, and stays in ++ until 60% or less. More often, it covers the surface of the substrate.₂The probability of particles increases and the antibacterial property deteriorates. At 100%, it is -.

Therefore, using 0.01μm TiO₂Adding 0.008 μm SnO to particles₂Particles, it is difficult to provide multi-functional materials with excellent antibacterial properties and excellent abrasion resistance. This is due to the larger particle size of SnO₂The smaller the vapor pressure of the particles, the less residual SnO₂If the particles are 0.0035μm, they will be present in TiO.₂The gap between the particles to improve the bonding strength, compared with 0.008μm with TiO₂SnO compared to voids between particles₂Large particles, SnO₂The particles cannot enter the void, but instead will be in the TiO₂The probability of particles is high.

It can be seen from the above that TiO should be buried₂SnO of the voids of particles₂Particle size to TiO₂The particle size is preferably 4/5 or less.

Example 8

Forming SnO on the surface of a 150 square tile substrate₂-A<img file="TW406031B_D0026.tif" />O₃-BaO glass (softening temperature 620 ° C) as a binder layer, coated with TiO on it by spraying₂After sol aqueous solution, it is fired at 750 ° C, cooled and solidified into a composite material, and then coated with SnO by spraying method.₂The sol aqueous solution is heat treated at 110 ° C, a more functional material. At this time TiO₂The sol aqueous solution was the same as in Example 6, and SnO₂The sol is used in 0.0035 μm.

The antibacterial test and the abrasion resistance test were carried out for the multifunctional material produced as described above, and the results are shown in Table 8 below.

<tables><img file="TW406031B_D0027.tif" /></tables>

Resistance to wear, with SnO₂The increase in the amount can improve the wear resistance. When the molar ratio is 20% or more, the sliding will not be damaged or changed without sliding for 40 times.

In the antibacterial test, the range of up to 20% or more may be ++ from +++ to 60% as in the case of no addition, but when the weight is increased, it covers the surface of the substrate TiO.₂The probability of particles is greatly increased, and the antibacterial property is deteriorated, and at 100%, it is -.

In this test due to SnO₂The sol is heat-treated at a lower temperature of 110 ° C, so sintering of the gasification-condensation mechanism as in Example 6 does not occur. However, the wear resistance can still be improved.₂Small particle size, that is, SnO with large specific surface area and strong adsorption force₂The particles are embedded in TiO₂Void between particles, making TiO₂The particles are firmly bonded to each other.

Example 9

Forming SiO on the surface of 150 square tile substrate₂-A<img file="TW406031B_D0028.tif" />O₃-BaO glass (softening temperature 620 ° C) into a binder layer on which TiO is spray coated₂After the sol aqueous solution is fired at 750 ° C, it is cooled and solidified into a composite material, and a copper acetate aqueous solution is applied thereon to be dried, and then irradiated with ultraviolet rays to reduce copper ions, and the photocatalyst layer is fixed, and the functional material is fixed. Here, a mercury lamp is used as an illumination lamp.

Here, the Cu particles fixed to the photocatalyst layer have an average size of about 0.004 μm.

The antibacterial test and the abrasion resistance test were carried out for the multifunctional material produced as described above, and the results are shown in Table 9.

<tables><img file="TW406031B_D0029.tif" /></tables>

In terms of wear resistance, the wear resistance is improved as the amount of Cu increases, and when the molar ratio is 20% or more, the sliding is not affected by the sliding for 40 times.

In the antibacterial test, the range of up to 20% or more was +++ as in the case of no addition, and since Cu itself had an antibacterial force, a large amount of addition did not reduce the antibacterial property.

However, it is possible to add TiO by a small amount of copper.₂The photocatalytic action of the particle layer is dominated, and the addition of a large amount of copper is governed by the action of copper. If only copper is expected to act, copper will slowly dissolve in the liquid, and its life is shorter than that of those without photocatalyst. Moreover, when the amount of copper added is too large, the cost is also high, so setting a too large amount of copper to add is not meaningful.

It can be seen from this embodiment that not only can be used as SnO₂Oxides such as metals such as copper can also be used as buried TiO₂Particles in the voids of the particle layer.

Example 10

Forming SiO on the surface of 150 square tile substrate₂-A<img file="TW406031B_D0030.tif" />O₃-BaO glass (softening temperature 620 ° C) into a layer of granules, on which TiO coating is applied by spraying₂After the sol aqueous solution is fired at 950 ° C, it is cooled and solidified into a composite material, and an aqueous copper acetate solution is applied thereon, and then ultraviolet rays are irradiated to reduce copper ions, and the photocatalyst layer is fixed, and the functional material is fixed.

At this time, it was irradiated with a BLB lamp and irradiated for several minutes. TiO₂The anatase phase is transferred to the rutile type during the heat treatment. TiO₂The film thickness was adjusted to 0.4 μm at the time of spraying.

The antibacterial alkali test and the abrasion resistance test were carried out on the multifunctional material prepared as described above. Those who were not added in the abrasion resistance test also gave good results in this temperature range. With or without the addition of copper, it can slide for 40 times without damage and does not change.

The antibacterial test is shown in Fig. 18. TiO when not added₂It is a rutile type, so it is a poor +. The antibacterial property can be improved by adding copper one by one. Moreover, when not only the BLB lamp is irradiated, the Cu loading amount is 0.7 μg/cm even when it is not irradiated.²The above can make the antibacterial activity ++, and the Cu loading is 1.2 μg/cm.²The above can make the antibacterial property +++.

From the above, it is known that the multifunctional material which is excellent in antibacterial property and abrasion resistance is still supported by Cu in an amount of 0.7 μg/cm.²More preferably, more preferably 1.2 μg/cm²the above.

As for the copper loading amount, it is possible to significantly increase the drying step before applying the drying step before applying the copper acetate aqueous solution. Show this relationship in Figure 19. This is due to the high concentration of metal ions during drying and photoreduction.

Moreover, when the optimum amount of copper is applied, the copper loading amount can be the highest (Fig. 20, Fig. 20 is a case of copper acetate having a Cu concentration of 1% by weight), and according to Fig. 20, the coating amount is 0.7 μg. /cm²Above, it can be 0.2mg/cm²~2.7mg/cm²To make it 1.2μg/cm²Above can be 0.3mg/cm²~2.4mg/cm²。

Example 11

Forming SiO on the surface of 150 square tile substrate₂-A<img file="TW406031B_D0031.tif" />O₃-BaO glass (softening temperature 680 ° C) into a binder layer on which TiO is spray coated₂After the sol aqueous solution is fired at 950 ° C, it is cooled and solidified into a composite material, and an aqueous silver nitrate solution is applied thereon, and then ultraviolet rays are irradiated to reduce silver ions, and the photocatalyst layer is fixed, and the functional material is fixed.

At this time, it was irradiated with a BLB lamp and irradiated for several minutes. TiO₂The anatase phase is transferred to the rutile type during the heat treatment. TiO₂The film thickness was adjusted to 0.4 μm at the time of spraying.

The multifunctional material prepared as described above was subjected to an antibacterial test and an abrasion resistance test. Those who were not added in the abrasion resistance test also gave good results in this temperature range. With or without the addition of silver, it can slide for 40 times without damage and does not change.

The antibacterial test is shown in Fig. 70. TiO when not added₂It is poor for the rutile type. However, when silver is added, it is improved. Not only the BLB lamp is irradiated, but the silver loading is 0.05 μg/cm even without irradiation.²The above can make the antibacterial property ++. Ag loading is 0.1μg/cm²Above the antibacterial can reach +++.

However, when the amount of silver is large, it turns from brown to black, and the appearance is not good, but the carrying amount of silver is 1 μg/cm.²It will not be colored when it is below.

From the above, the amount of silver supported is 0.05 μg/cm.²~1μg/cm², preferably at 0.1 μg/cm²~1μg/cm²It is appropriate.

Example 12

Forming SiO on the surface of 150 square tile substrate₂-A<img file="TW406031B_D0032.tif" />O₃-BaO glass (softening temperature 680 ° C) into a layer of granules, on which TiO coating is applied by spraying₂After the sol aqueous solution is fired at 950 ° C, it is cooled and solidified into a composite material, and a silver nitrate aqueous solution is applied thereon to be dried, and then irradiated with ultraviolet rays to reduce silver ions, and the photocatalyst layer is fixed, and a multi-functional material is fixed.

At this time, it was irradiated with a BLB lamp and irradiated for several minutes. TiO₂The anatase phase is transferred to the rutile type during the heat treatment.

For various materials made as described above, change various TiO₂The film thickness was tested for abrasion resistance and antimicrobial test.

In the abrasion resistance test, it has a good effect within the range of 2 μm in this test, and it will not be damaged after 40 times of sliding back and forth, and it does not change.

In the antibacterial test, when the film thickness is 0.1 μm or more, it is ++, and when it is 0.2 μm or more, it is +++. Therefore TiO₂The film thickness is preferably 0.1 μm or more, and preferably 0.2 μm or more.

Example 13

Forming SiO on the surface of 150 square tile substrate₂-A<img file="TW406031B_D0033.tif" />O₃-BaO glass (softening temperature 620 ° C) into a binder layer on which TiO is spray coated₂After the sol aqueous solution is fired at 750 ° C, it is cooled and solidified into a composite material, and a silver nitrate aqueous solution is applied thereon to be dried, and then irradiated with ultraviolet rays to fix silver ions and fixed to the photocatalyst layer. Thereafter, it is fired at 900 ° C to 1000 ° C to cool and cure the more functional material.

At this time, the illumination lamp was irradiated with a BLB lamp for several minutes. Also, TiO₂In the heat treatment process, the anatase phase is transferred to the rutile type, and the silver system fixed on the surface is changed from black to white with heat treatment, so it can be changed to silver oxide during firing. However, since the silver was adhered and fixed in a dispersed manner, the growth of silver particles was not observed before and after the firing.

The multifunctional material prepared as described above was subjected to an antibacterial test and an abrasion resistance test.

In the anti-wear test, good results can be obtained without adding this temperature range. When adding or not adding silver, it can be slid back and forth for 40 times without damage, and can not be changed.

The antibacterial test is shown in Figure 70.₂It is a rutile type, so it is a poor +. However, when silver is added, the antibacterial property is improved.

Example 14

Forming SiO on the surface of 150 square tile substrate₂-A<img file="TW406031B_D0034.tif" />O₃-BaO glass (softening temperature 620 ° C) into a binder layer on which TiO is spray coated₂After the sol aqueous solution is fired at 820 ° C, it is cooled and solidified into a composite material, and a silver nitrate aqueous solution is applied thereon to be dried, and then irradiated with ultraviolet light to reduce silver ions to fix the photocatalyst layer, and then coated with 0.1 cc/cm.²0.1 Mol /<img file="TW406031B_D0035.tif" />Aqueous KI, irradiated with UV light for 5 seconds, a much more functional material. At this time, the carrying amount of silver is 2 μg/cm.²。

Coating 0.1cc/cm²0.1 Mol /<img file="TW406031B_D0036.tif" /> The aqueous solution of KI was irradiated with ultraviolet rays for another 5 seconds, so that the original material which was originally dark brown was bleached to white, and the appearance was better.

Example 15

Forming SiO on the surface of 150 square tile substrate₂-A<img file="TW406031B_D0037.tif" />O₃-BaO glass (softening temperature 620) as an adhesive layer, sprayed with TiO₂The sol aqueous solution is fired at 820 ° C, cooled and solidified into a multifunctional material, and the material is tilted and irradiated with ultraviolet light, and the bath water taken from the public bath is continuously dripped in the multifunctional material cycle. Observe the change in the bath water. For the sake of comparison, the same equipment was used to drip the bath water onto the substrate on which the photocatalyst layer was not provided. After the 14th day, it was observed that the water in the bath was dripped in the water of the multifunctional material and the bath water on the substrate on which the photocatalyst layer was not dropped. The turbidity did not show a particular difference, but the difference in sludge odor was observed. That is, the bath water on the substrate without the photocatalyst layer can be smelled of sludge, and mucus-like mucus and organic precipitate can be seen on the substrate, and the multifunctional material is dropped. The bath used water did not see this phenomenon. It can be seen from the above simulation test that the multifunctional material can be used as a stone in a man-made waterfall or a fountain in a water circulation mode such as a park or a department store.

As can be seen from the above description, since the photocatalyst layer is fixed by an adhesive layer formed of a material having a lower softening temperature than the substrate, in particular, the photocatalyst particles constituting the surface layer portion of the photocatalyst layer are not buried in the adhesive layer, so the photocatalyst The surface of the particle is substantially exposed to the outside, and the photocatalytic effect can be sufficiently exerted. Further, since a part of the photocatalyst particles constituting the lower layer of the photocatalyst layer is buried in the adhesive layer, the retention of the photocatalyst layer can be remarkably enhanced, and it is difficult to peel off.

Fig. 21 is a view showing a manufacturing step of another embodiment. In this embodiment, a thermoplastic such as inorganic glass or a thermoplastic resin is used as the substrate 1, and the photocatalyst layer 2 is directly formed on the surface of the thermoplastic substrate 1.

That is, as shown in Fig. 21(a), the thermoplastic substrate 1 is prepared, and then TiO is formed on the surface of the thermoplastic substrate 1 as shown in Fig. 2(b).₂The photocatalyst layer 2 is formed by photocatalyst particles such as particles. Then, after heat treatment, as shown in the figure (c), the lower layer of the thermoplastic substrate is precipitated into the thermoplastic substrate, and the thermoplastic substrate is solidified and buried in the thermoplastic substrate, and is firmly maintain. Further, the photocatalyst particles 3 constituting the surface layer contacting the outside air in the photocatalyst layer 2 are bonded by the potential energy, the mutual attraction force between the molecules, or the sintering.

The preferred conditions and the like of this embodiment are the same as those of the above embodiment, and are specifically described below.

Example 16

Square SiO in 150₂-A<img file="TW406031B_D0038.tif" />O₃-Na/K₂O glass material is formed into the surface of the glass substrate, and 15% TiO is coated by spraying method.₂Aqueous sol solution to form TiO with a film thickness of 0.8 μm₂Layer, which is then laminated with TiO₂The glass substrate of the layer is placed in a ceramic film-forming type having excellent release properties, and then each embodiment is heated and fired in a rolling kiln at different atmospheric temperatures, and then cooled to cure the functional glass.

TiO as referred to herein₂The aqueous sol solution refers to hydrolyzing TiC under hydrothermal conditions in the range of 100-200 ° C in an autoclave.<img file="TW406031B_D0039.tif" />Obtain anatase TiO with a crystallite diameter of 0.007~0.2μm₂The ore is dispersed in the sol state in an amount of from 5% to tens of % in an acidic aqueous solution such as nitric acid or hydrochloric acid or an alkaline aqueous solution such as ammonia, and an organic acid of triethylamine and trimethylolamine in a range of 0.5% or less is added to improve the dispersibility. Salt, isovaleryl alcohol, trimethylolpropane, etc. are used as surface treatment agents. Also, TiO₂The particle size of the sol was processed by SEM observation, and the crystal grain size was calculated from the integral width of the powder X-ray diffraction.

Further, the coating method is a method of applying spray, but the same results can be obtained by the dip coating method or the spin coating method.

Antibacterial and anti-wear properties are evaluated for the multifunctional materials.

The bactericidal effect of the antibacterial strain test on Escherichia Coli W3110 strain. Drop the bacterial liquid 0.15m on the uppermost surface of the multifunctional material sterilized with 70% ethanol in advance.<img file="TW406031B_D0040.tif" />(1~5×10⁴CFU), a glass plate (10 × 10 cm) was placed to adhere to the uppermost surface of the substrate as a sample. After illuminating the white light for 30 minutes (3,500 candelas), the sterilized gauze was used to wipe the irradiated sample and the sample liquid held under the light-shielding condition, and recovered in 10 m.<img file="TW406031B_D0041.tif" />In the physiological saline solution, the survival rate of the bacteria was determined as an evaluation index.

The abrasion resistance is made by sliding the rubber with a plastic wiping rubber, and the appearance is evaluated.

The use of SiO is shown in Table 10 below.₂-A<img file="TW406031B_D0042.tif" />O₃-Na/K₂When the glass substrate composed of the O glass material has an effect on the antibacterial property and the abrasion resistance when the baking temperature is changed.

<tables><img file="TW406031B_D0043.tif" /></tables>+++: The survival rate of coliform is below 10%

++: Survival rate of coliforms is 10% or more and 30% or less

+: The survival rate of coliform is 30% or more and 70% or less

-: Survival rate of coliforms is over 70%

: After 40 round trips, the damage did not occur.

: Damage occurred after 10-40 sliding, photocatalyst layer (TiO₂Membrane)

: Initiation of damage by 5-10 sliding, photocatalyst layer (TiO₂Membrane)

×: visible damage after 5 times of sliding, photocatalyst layer (TiO₂Membrane)

Here, SiO₂-A<img file="TW406031B_D0044.tif" />O₃-Na/K₂The glass substrate composed of O has a specific gravity of 2.4 and a softening temperature of 680 °C. Also, the TiO obtained in Table 10₂It is an anatase type of NO.1~3, with a specific gravity of 3.9, NO.4, and 5 series rutile, and its specific gravity is 4.2.

In Table 10, the firing temperature of NO.1 is only 20 °C higher than the softening temperature of the glass substrate, and the viscosity of the glass substrate cannot be sufficiently reduced, so that the anatase TiO which constitutes the lowermost layer of the photocatalyst layer is formed.₂It cannot be fully embedded in the glass substrate, and for this reason, it is peeled off only by sliding 5 to 10 times in the abrasion resistance test. In addition, the antibacterial property is due to the use of anatase with excellent photocatalytic activity, and TiO-DTA observation of TiO at 300 ° C or higher.₂The organic components of the sol have almost been decomposed, gasified, and attached to TiO.₂The dispersing agent such as the surface treatment agent on the surface should be vaporized, and the firing temperature is again 700 ° C, so the processing temperature is quite high and the excellent value of ++ is obtained.

The NO.3~5 series firing temperature is 800°C or more and 1000°C or less. In terms of durability, it is possible to withstand 40 or more round-trip sliding tests without being changed to excellent. The reason should be the surface TiO₂The particles form a neck after initial firing. Moreover, when treated at 1100 ° C, the TiO on the surface of the multifunctional glass was found after being cooled and solidified and taken out from the rolling kiln.₂The layer has cracked. This is determined by TMA.₂Judging from the test piece, knowing the TiO₂A medium-term sintering generator that particleizes significant volume shrinkage.

The antibacterial properties of NO.4 and NO.5 are poor, and two reasons can be guessed.₂The particles have been phase transferred to rutile type, and the other is that the firing temperature is 300 ° C higher than the softening temperature of the glass substrate, and the viscosity of the glass substrate becomes too low, and the TiO which constitutes the photocatalyst layer₂The particles are buried in the glass substrate. Here TiO₂The phase transfer of particles to the rutile type is not the cause. Rutile TiO₂Although anatase TiO₂Slightly poor, but still has some photocatalytic activity. For example, spraying TiO directly₂The sol was fired on a porous alumina substrate, and the sample which was cooled and solidified at 950 ° C was still antibacterial. Therefore, it can be seen that the firing temperature is higher than the softening temperature of the glass substrate by 300 ° C, the viscosity of the glass substrate is too low, and the TiO which constitutes the photocatalyst layer₂The inclusion of particles in a glass substrate should also be a cause.

Further, when Ti and Si (the main component of the glass substrate) in the cross-sectional direction of the sample were analyzed by elements such as EPMA, a mixed layer of Ti and Si was observed, and the TiO of the photocatalyst particles was confirmed.₂Has been buried in it.

From the above Example 14, that is, at least the photocatalyst is TiO₂, the glass substrate is SiO₂-A<img file="TW406031B_D0045.tif" />O₃-Na/K₂The following facts can be confirmed when the composition of O is made.

1 When the firing temperature is 20 ° C higher than the softening temperature of the glass substrate, and the multi-functional glass is produced at a temperature not higher than 300 ° C, a multifunctional glass having excellent antibacterial properties and abrasion resistance can be produced. The reason for this is that the viscosity of the glass substrate at this temperature has been adjusted to be suitable for embedding TiO in the glass substrate.₂The value is due to.

21 versatile glass systems were confirmed to be TiO₂The particles are embedded in the glass substrate.

3 When the firing temperature is 800 ° C or more and 1000 ° C or less, the abrasion resistance is not changed after 40 or more sliding tests, and the abrasion resistance is excellent, and it is supposed to be TiO.₂The neck is formed between the particles and is firmly bonded.

Example 17

SiO at 100 × 100 × 5₂-A<img file="TW406031B_D0046.tif" />O₃-PbO is composed of the surface of the glass substrate, and 15% TiO is coated by spraying₂Aqueous sol solution (same as in Example 16) to form TiO having a film thickness of 0.8 μm₂Layer, which is then laminated with TiO₂The glass substrate of the layer is placed in a ceramic film type having excellent release properties, and each embodiment is heated and fired in a rolling kiln at different atmospheric temperatures, and then cooled to cure a functional glass.

The use of SiO is shown in Table 11 below.₂-A<img file="TW406031B_D0047.tif" />O₃- In the case of a glass substrate composed of PbO, the effect on the antibacterial property and the abrasion resistance is changed when the baking temperature is changed.

<tables><img file="TW406031B_D0048.tif" /></tables>

Here SiO₂-A<img file="TW406031B_D0049.tif" />O₃-PbO composition of the glass substrate softening temperature of 540 ° C, specific gravity of 3.8, the resulting TiO₂The crystal forms are all anatase.

In the abrasion resistance test of Table 11, NO.6 was peeled off by the slip after 10 times or less, but NO.7,8 would not be damaged if it slipped 10 times or more, and NO.9, NO.10 would slide 40 times. The above will not be damaged.

NO.9,10 shall not be damaged when sliding more than 40 times. The firing temperature shall be 800 °C or higher, in TiO.₂Neck formation between particles, TiO₂The particles are firmly bonded to each other.

NO.6 is damaged or peeled after sliding 10 times or less. This is because the firing temperature is 20 °C higher than the softening temperature of the glass substrate. The viscosity of the glass substrate cannot be sufficiently reduced, and the anatase of the lowermost layer of the photocatalyst layer is formed. Mineral TiO₂The particles cannot be fully embedded in the glass substrate.

Compared with NO.7,8, it will not be damaged if it slides more than 10 times. This should be the difference between the firing temperature and the softening temperature of the glass substrate, although the temperature of the neck is not reached. The viscosity of the material is TiO₂It can be caused by the value embedded in the adhesive moderately.

On the other hand, in the antibacterial test of Table 11, NO.6~NO.9 gave good results of +++ or ++, but NO.10 was only +. This is because the firing temperature is 320 ° C higher than the softening temperature of the glass substrate, and the viscosity of the glass substrate is too low, and the TiO which constitutes the photocatalyst layer₂The particles are embedded in a glass substrate.

Example 18

In SiO₂-A<img file="TW406031B_D0050.tif" />O₃-BaO consists of a 100×100×5 glass substrate coated with 15% TiO by spraying₂Aqueous sol solution (same as in Example 1) to form TiO having a film thickness of 0.8 μm₂Layer, which is then laminated with TiO₂The glass substrate of the layer is placed in a ceramic mold having excellent release properties, and then each embodiment is heated and fired in a niobium carbide heating furnace at different atmospheric temperatures to be cooled and solidified.

Table 12 below shows the effect on the antibacterial property and the abrasion resistance when the firing temperature of the above-mentioned multifunctional glass is changed.<tables><img file="TW406031B_D0051.tif" /></tables>

Here SiO₂-A<img file="TW406031B_D0052.tif" />O₃The softening temperature of the glass substrate composed of -BaO is 620 ° C, the specific gravity is 2.8, and the TiO on the multifunctional material₂The crystal type NO. 11 to 13 is anatase type, and the NO. 14 type is rutile type.

In the abrasion resistance test in Table 12, the NO.11 system was damaged by slipping 5 times or less, and the NO.12 system was not damaged 10 times or more, and NO.13,14 did not slide even 40 times or more. It is damaged and has excellent results.

NO.13,14 which is not damaged by sliding more than 40 times, the firing temperature is above 800 °C, TiO₂Neck formation between particles, TiO₂The particles are firmly bonded to each other.

If it is slid 10 times or less, it will be damaged. The peeling NO.11 is only because the firing temperature is higher than the softening temperature of the glass substrate by 20 °C. The viscosity of the glass substrate cannot be sufficiently reduced, and the anatase TiO which constitutes the lowermost layer of the photocatalyst layer is formed.₂The particles are not fully embedded in the glass substrate.

In contrast, NO.12 has not been damaged after more than 10 times of sliding. This is because the temperature does not reach the temperature of the neck, but the difference between the firing temperature and the softening temperature of the glass substrate can adjust the glass substrate. Stickiness to moderately bury TiO₂Due to the value in the glass substrate.

On the other hand, in the antibacterial test of Table 12, NO. 11 to 13 series +++ or ++ had excellent effects, but NO. 14 was one. This system is due to TiO₂Will become rutile type, the firing temperature is 320 ° C higher than the softening temperature of the glass substrate, the viscosity of the glass substrate is too low, and the TiO which constitutes the photocatalyst layer₂Two reasons for the particles being buried in the glass substrate.

Example 19

In each of the examples, 100×100×5 glass substrates with different specific gravity were used, and 15% TiO was coated on the surface of the substrate by spraying.₂Aqueous sol solution to form TiO with a film thickness of 0.8 μm₂Layer, which is then laminated with TiO₂The glass substrate of the layer is placed in a ceramic film-forming type having excellent release properties, and then each embodiment is heated and fired in a rolling kiln at different atmospheric temperatures, and then cooled to cure the functional glass.

Table 13 below shows the effect of improving the specific gravity of the glass substrate of the above multifunctional material on the antibacterial property and the abrasion resistance.

<tables><img file="TW406031B_D0053.tif" /></tables>

In the antibacterial test, NO.15~18 had excellent +++ results. The firing temperature is higher than the softening temperature of the glass substrate by 30° C. or more and 300° C. or less. The difference between the firing temperature and the softening temperature of the glass substrate can be adjusted to adjust the viscosity of the glass substrate to a suitable degree of TiO.₂This result is obtained by embedding the values in the glass substrate.

In the abrasion resistance, the NO.15 is slipped 5 times or less, that is, it is damaged and peeled off, but NO. 16 to 18 are slipped 10 times or more and are not damaged.

According to the investigation, the reason should be that NO.15 is different from the others, and the specific gravity of the glass substrate is higher than that of TiO.₂The ratio is large, so the anatase TiO which constitutes the lowermost layer of the photocatalyst layer₂The particles are not fully embedded in the glass substrate.

Therefore, it is known that the wear resistance of the multifunctional glass substrate is also affected by TiO.₂The specific gravity of the glass substrate is proportional to the specific gravity of the glass substrate.₂It also causes poor wear resistance when the ratio is large.

Example 20

SiO in 150 square₂-A<img file="TW406031B_D0054.tif" />O₃-BaO composition (softening temperature 620 ° C) into the surface of the glass substrate, spray mixture TiO₂Sol and SnO₂The stirred aqueous solution of the sol was fired at 750 ° C, cooled, and the functionally more material was cured.

Also, TiO₂Sol concentration is 4-6 wt%, with NH₃The aqueous solution was adjusted to pH 11, TiO₂The crystallite size of the particles is 0.01 μm, SnO₂The crystallite size of the particles was 0.0035 μm.

The multifunctional materials prepared as described above are shown in Table 14 and changed to TiO.₂With SnO₂Total amount of SnO₂The effect of the amount (Morby) on the antibacterial property and the abrasion resistance is shown in the table.

<tables><img file="TW406031B_D0055.tif" /></tables>

Resistance to wear, with SnO₂The increase in the amount can improve the wear resistance. When 10% or more is added, it will not be damaged or changed without sliding for 40 times.

In the antibacterial test, the range of up to 20% or more may be ++ when it is +++ to 60% as in the case of no addition, but when it is added, the surface of the substrate is covered with TiO.₂The probability of particles is greatly increased, and the antibacterial property is deteriorated, and at 100%, it is -.

So SnO₂The amount added is in the case of Moby, in TiO₂With SnO₂A multifunctional glass having an antibacterial property and an excellent abrasion resistance can be provided in an amount of 10% or more and 60% or less, preferably 10% or more and 20% or less.

Here, the wear resistance can be followed by SnO₂The increase in the amount is increased, and the operation can be explained in accordance with the description of Fig. 17 above.

As described above, the glass substrate is maintained on the surface of the glass substrate with TiO₂In the composite of the particle layer, the TiO exposed on the outermost surface₂Interstitial void filling of SnO₂When the particles are fired at 600 ° C or higher, cracking does not occur, and TiO is bonded.₂The neck between the particles improves the wear resistance.

Comparative Example 21

As in Embodiment 20, in 150 square SiO₂-A<img file="TW406031B_D0056.tif" />O₃-BaO composition (softening temperature 620 ° C) on the surface of the substrate, spray coating, mixing, stirring TiO₂Sol and SnO₂After the aqueous solution of the sol was fired at 750 ° C, the functional glass was cooled and solidified.

Also, TiO₂The concentration of the sol was 4 to 6% by weight, adjusted to pH 11 with an aqueous ammonia solution, and the crystallite size was 0.01 μm as in Example 20, SnO.₂The crystallite size of the particles used was a larger 0.008 μm.

The antibacterial test and the abrasion resistance test were carried out on the multifunctional glass produced as described above, and the results of comparison with Example 20 are shown in Table 15 below.

<tables><img file="TW406031B_D0057.tif" /></tables>

As a result, a SnO of 0.008 μm was known.₂The effect of particles on improving wear resistance is compared to the use of SnO at 0.0035 μm.₂Particles are weak, on TiO₂With SnO₂When the combined molar ratio is more than 60%, it can be achieved by sliding 40 times without damage and changing.

In the antibacterial test, using SnO of 0.0035μm₂In the case of particles, the range of 20% or more can still be +++ as in the case of no addition, and stays in ++ until 60% or less. More often, it covers the surface of the glass substrate.₂The probability of particles increases and the antibacterial property deteriorates. At 100%, it is -.

Therefore, using 0.01μm TiO₂Adding 0.008 μm SnO to particles₂Particles, it is difficult to provide multifunctional glass with excellent antibacterial properties and abrasion resistance. This is due to the larger particle size of SnO₂The smaller the vapor pressure of the particles, the less residual SnO₂If the particles are 0.0035μm, they will be present in TiO.₂The gap between the particles to improve the bonding strength, compared with 0.008μm with TiO₂SnO compared to voids between particles₂Large particles, SnO₂The particles cannot enter the void, but instead will be in the TiO₂The probability of particles is high.

It can be seen from the above that TiO should be buried₂SnO of the voids of particles₂Particle size to TiO₂The particle size is preferably 4/5 or less.

Example 22

In 150 square square SnO₂-A<img file="TW406031B_D0058.tif" />O₃-BaO composition (softening temperature 620 ° C) into the surface of the glass substrate, spraying TiO on it by spraying₂After sol aqueous solution, it is fired at 750 ° C, cooled and solidified into a composite material, and then coated with SnO by spraying method.₂The sol aqueous solution is heat treated at 110 ° C, a more functional material. At this time TiO₂The sol aqueous solution was the same as in Example 20, and SnO₂The sol is used in 0.0035 μm.

The antibacterial test and the abrasion resistance test were carried out for the multifunctional material produced as described above, and the results are shown in Table 16 below.

<tables><img file="TW406031B_D0059.tif" /></tables>

Resistance to wear, with SnO₂The increase in the amount can improve the wear resistance. When the molar ratio is 20% or more, the sliding will not be damaged or changed without sliding for 40 times.

In the antibacterial test, the range of up to 20% or more may be ++ when it is +++ to 60% as in the case of no addition, but when it is added, the surface of the substrate is covered with TiO.₂The probability of particles is greatly increased, and the antibacterial property is deteriorated, and at 100%, it is -.

In this test due to SnO₂The sol is heat-treated at a lower temperature of 110 ° C, so sintering of the gasification-condensation mechanism as in Example 5 does not occur. However, the wear resistance can still be improved.₂Small particle size, that is, SnO with large specific surface area and strong adsorption force₂The particles are embedded in TiO₂Void between particles, making TiO₂The particles are firmly bonded to each other.

Example 23

Square SiO in 150₂-A<img file="TW406031B_D0060.tif" />O₃-BaO composition (softening temperature 620 ° C) into the surface of the glass substrate, on which TiO coating is applied by spraying₂After the sol aqueous solution is fired at 750 ° C, it is cooled and solidified into a composite material, and a copper acetate aqueous solution is applied thereon to be dried, and then irradiated with ultraviolet rays to reduce copper ions, and the photocatalyst layer is fixed, and the functional material is fixed. Here, a mercury lamp is used as an illumination lamp.

Here, the Cu particles fixed to the photocatalyst layer have an average size of about 0.004 μm.

The antibacterial test and the abrasion resistance test were carried out on the multifunctional glass produced as described above, and the results are shown in Table 17.

<tables><img file="TW406031B_D0061.tif" /></tables>

In terms of wear resistance, the wear resistance is improved as the amount of Cu increases, and when the molar ratio is 20% or more, the sliding is not affected by the sliding for 40 times.

In the antibacterial test, the range of up to 20% or more was +++ as in the case of no addition, and since Cu had its own antibacterial power, it was not found to reduce the antibacterial property in a large amount.

However, it is possible to add TiO by a small amount of copper.₂The photocatalytic action of the particle layer is dominated, and the addition of a large amount of copper is governed by the action of copper. If only copper is expected to act, copper will slowly dissolve in the liquid, and its life is shorter than that of those without photocatalyst. Moreover, when the amount of copper added is too large, the cost is also high, so setting a too large amount of copper to add is not meaningful.

It can be seen from this embodiment that not only can be used as SnO₂Oxides such as metals such as copper can also be used as buried TiO₂Particles in the voids of the particle layer.

Example 24

Square SiO in 150₂-A<img file="TW406031B_D0062.tif" />O₃-BaO composition (softening temperature 620 ° C) into the surface of the glass substrate, spray coating TiO₂After the sol aqueous solution is fired at 950 ° C, it is cooled and solidified into a composite material, and a copper acetate aqueous solution is applied to the material, and then the light containing ultraviolet rays is irradiated to fix the photocatalyst layer and the multi-functional glass while reducing copper ions.

At this time, it was irradiated with a BLB lamp and irradiated for several minutes. TiO₂The anatase phase is transferred to the rutile type during the heat treatment. TiO₂The film thickness was adjusted to 0.4 μm at the time of spraying.

The multifunctional glass produced as described above was subjected to an antibacterial test and an abrasion resistance test. Those who were not added in the abrasion resistance test also gave good results in this temperature range. With or without the addition of copper, it can slide for 40 times without damage and does not change.

The antibacterial test is shown in Fig. 22. TiO when not added₂It is a rutile type, so it is a poor +. When the copper is added, the antibacterial property can be improved. When the BLB lamp is not irradiated, the copper loading amount is 0.7 μg/cm even if it is not irradiated.²The above can make the antibacterial activity ++, and the Cu loading is 1.2 μg/cm.²The above can make the antibacterial property +++.

From the above, it is known that the multifunctional material which is excellent in antibacterial property and abrasion resistance is still supported by Cu in an amount of 0.7 μg/cm.²More preferably, more preferably 1.2 μg/cm²the above.

As for the copper loading amount, it is possible to significantly increase the drying step before applying the drying step before applying the copper acetate aqueous solution. Show this relationship in Figure 23. This is due to the high concentration of metal ions during drying and photoreduction.

Moreover, when the optimum amount of copper is applied, the copper loading amount can be the highest (Fig. 24 is a case of copper acetate having a Cu concentration of 1% by weight), and according to Fig. 20, the coating amount is required to be 0.7 μg/cm.²Above, it can be 0.2mg/cm²~2.7mg/cm²To make it 1.2μg/cm²Above can be 0.3mg/cm²~2.4mg/cm²。

Example 25

Square SiO in 150₂-A<img file="TW406031B_D0063.tif" />O₃-BaO composition (softening temperature 680 ° C) into the surface of the glass substrate, spray coating TiO₂After the sol aqueous solution is fired at 950 ° C, it is cooled and solidified into a composite material, and a silver nitrate aqueous solution is applied to the material, and then the light containing ultraviolet rays is irradiated to fix the photocatalyst layer and the multi-functional glass while reducing the silver ions.

At this time, it was irradiated with a BLB lamp and irradiated for several minutes. TiO₂The anatase phase is transferred to the rutile type during the heat treatment. TiO₂The film thickness was adjusted to 0.4 μm at the time of spraying.

The multifunctional glass produced as described above was subjected to an antibacterial test and an abrasion resistance test. Those who were not added in the abrasion resistance test also gave good results in this temperature range. With or without the addition of silver, it can slide for 40 times without damage and does not change.

The antibacterial test is shown in Fig. 25. TiO when not added₂It is poor for the rutile type. However, when silver is added, it is improved. Not only the BLB lamp is irradiated, but the silver loading is 0.05 μg/cm even without irradiation.²The above can make the antibacterial property ++. Ag loading is 0.1μg/cm²Above the antibacterial can reach +++.

However, when the amount of silver is large, it turns from brown to black, and the appearance is not good, but the carrying amount of silver is 1 μg/cm.²It will not be colored when it is below.

From the above, the amount of silver supported is 0.05 μg/cm.²~1μg/cm², preferably at 0.1 μg/cm²~1μg/cm²。

Example 26

Square SiO in 150₂-A<img file="TW406031B_D0064.tif" />O₃-BaO glass (softening temperature 680 ° C), the surface of the glass substrate is spray coated with TiO₂After the sol aqueous solution is fired at 950 ° C, it is cooled and solidified into a composite material, and a silver nitrate aqueous solution is applied to the material, and then the light containing ultraviolet rays is irradiated to fix the photocatalyst layer and the multi-functional glass while reducing the silver ions.

At this time, the illumination lamp was irradiated with a BLB lamp for several minutes. TiO₂The anatase phase is transferred to the rutile type during the heat treatment.

Changing TiO for the multifunctional glass produced as described above₂The film thickness was tested for the abrasion resistance and the antibacterial test.

In the abrasion resistance test, it has a good effect within the range of 2 μm in this test, and it does not suffer damage after 40 times of sliding back and forth, and does not change.

In the antibacterial test, when the film thickness is 0.1 μm or more, it is ++, and when it is 0.2 μm or more, it is +++. Therefore TiO₂The film thickness is preferably 0.1 μm or more, and preferably 0.2 μm or more.

As is apparent from the above description, the photocatalyst particles are fixed to the thermoplastic substrate, and the photocatalyst particles constituting the surface layer portion of the photocatalyst layer are not embedded in the thermoplastic substrate. Therefore, the photocatalyst particles are substantially exposed to the outside of the surface of the photocatalyst particles. Play a photocatalytic effect. Further, since the particles constituting the lower layer of the photocatalyst layer in the photocatalyst particles are partially embedded in the thermoplastic substrate, the retention of the photocatalyst layer can be remarkably enhanced, and it is difficult to peel off.

Fig. 26 and Fig. 27 are conceptual diagrams of basic contours when the cross-sectional direction of the multifunctional material is observed by EPMA (Electronic Line Microanalyzer). From this, it can be seen that, starting from the surface of the external gas, there is a region (A region) which constitutes a certain concentration of the constituent photocatalyst layer 2, and then the composition of the photocatalyst layer is gradually reduced. Further, the components constituting the amorphous layer (adhesive layer) are present in the absence or in a very small amount on the surface, and gradually increase the concentration to the inside. When it reaches a certain thickness, it becomes a certain concentration (B zone). Here, the A region is defined as a photocatalyst layer, the B region is an amorphous layer, and the middle C region is an intermediate layer. However, Fig. 26 is only a conceptual diagram for convenience of explanation. Actually, as shown in Fig. 27, the concentration specified in Fig. 26 is often changed in concentration due to the manufacturing process. At this time, as shown in Fig. 27, the minimum concentration values that reach the area corresponding to a certain area (A' area, B' area) are regarded as A' area and C' area, respectively, B' area and C' area. The realm of the district.

The thickness of the photocatalyst layer refers to the thickness of the A region or the A' region, and the thickness of the intermediate layer refers to the thickness of the C region or the C' region.

The thickness of the intermediate layer can be varied by controlling the speed at which the photocatalyst particles move toward the softened amorphous, and possibly moving the time. The moving speed can control the difference in specific gravity between the photocatalyst particles and the amorphous layer, the firing rate, the atmospheric pressure, and the like. Again, the time that may be moved can be varied by varying the amount of time the amorphous material remains at the softening temperature.

The thickness of the intermediate layer can be made to be more than 1/3 of the thickness of the photocatalyst layer to improve the adhesion.

The specific embodiments are described below.

Example 27

Formation of SiO on a 10cm square alumina substrate by spray coating₂-A<img file="TW406031B_D0065.tif" />O₃-Na/K₂O-type amorphous layer, after drying and firing, coating an average particle size of 0.01 μm TiO by spraying₂The sol aqueous solution was changed at 850 ° C for a period of time, and was fired to form an anatase TiO of 0.2 μm, 0.5 μm, and 1 μm film thickness.₂film. Then spray a copper acetate solution to the anatase TiO₂The film was then subjected to photoreduction (light source: 20 W BLB lamp, distance from the light source to the sample of 10 cm, irradiation time of 30 seconds) to obtain a sample. The sample obtained by the cross-sectional element analysis (Ti, Si) of EPMA was used to measure the film thickness, and the antibacterial property and the abrasion resistance were evaluated.

The bactericidal effect of the antibacterial strain test on Escherichia Coli W3110 strain. Drop the bacterial liquid 0.15m on the uppermost surface of the multifunctional material sterilized with 70% ethanol in advance.<img file="TW406031B_D0066.tif" />(1~5×10⁴CFU), a glass plate (10 × 10 cm) was placed to adhere to the uppermost surface of the substrate as a sample. After illuminating the white light for 30 minutes (3,500 candelas), the sterilized gauze was used to wipe the irradiated sample and the sample liquid held under the light-shielding condition, and recovered in 10 m.<img file="TW406031B_D0067.tif" />In the physiological saline solution, the survival rate of the bacteria was determined as an evaluation index. The evaluation criteria are as shown in Table 1 above.

The results are shown together in Table 18, and the antibacterial properties were +++. The abrasion resistance was also or , and both of them had good results. The ratio of the thickness of the intermediate layer to the thickness of the photocatalyst layer was 1/3 or more.

<tables><img file="TW406031B_D0068.tif" /></tables>

Comparative Example 28

Applying an average particle size of 0.01 μm TiO on a 10 cm square alumina substrate by spray coating₂Ammonia dispersion of sol, calcined at 850 ° C to obtain a 1 μm film thickness anatase TiO₂film. Then spray a copper acetate solution to the anatase TiO₂The film was then photoreduced (light source: 20 W BLB lamp, light source to sample distance 10 cm, irradiation for 30 seconds) to obtain a sample. The antibacterial property and the abrasion resistance of the obtained sample were evaluated.

As a result, the antibacterial property was excellent +++, but the abrasion resistance was slightly insufficient.

As apparent from the above description, the photocatalyst layer is held on the surface of the substrate by the amorphous layer, and the photocatalyst layer is a multifunctional material in which the upper layer portion is exposed to contact with the outside air, and the photocatalyst layer particles are bonded to each other to have a photocatalytic function. The intermediate layer between the amorphous layer and the photocatalyst layer can be continuously changed to further improve the adhesion between the photo-contact film and the substrate, and the peeling resistance can be improved. The thickness of the intermediate layer is more than 1/3 of the thickness of the photocatalyst layer to further improve the adhesion.

Next, the formation of the photocatalyst layer 2 by sintering will be described. Figure 1 (a) is the former TiO₂State diagram before particle sintering, (b) State diagram after sintering, as shown in Fig. 1 (a), coating TiO on the surface of the substrate 1₂The sol of the particle 3 is subjected to heat treatment (sintering) to increase the film strength, that is, the crack 2a is extremely likely to occur as shown in Fig. 1(b).

According to the speculation, the reason should be that the phase transfer to the rutile type causes volume shrinkage (increased density), in addition to the pre-sintering TiO₂The spacing between particles 101 is L₀After sintering into a rutile type, it will diffuse into the volume of the other party and shorten the interval between the particles to be L.₁(L₁&lt;L₀), the result is cracking.

So after sintering, it can be combined with TiO₂Particle 3 neck solidified SnO₂Thicken the neck to strengthen TiO₂The particles 3 are bonded to each other to increase the film strength.

When forming the photocatalyst layer 2 as described above, it is attached to TiO.₂Mixed SnO in sol₂The sol is applied to the substrate 1 after being stirred, and heat-treated (sintered) at a predetermined temperature.

In addition, TiO₂The sol concentration is adjusted to about 4 to 6% by weight, with NH₃Temperature adjusted to pH 11, TiO₂The average initial particle size of the particles is 0.01 μm (10 nm), SnO₂Sol concentration system 10% by weight, with NH₃The solution was adjusted to pH 11, SnO₂The average initial particle diameter of the particles was 0.0035 μm. The average initial particle diameter shown here means the crystallite size (initial particle) obtained from the half-value width of the XRD (X-ray diffraction).

Here at SnO₂Steam pressure is higher than TiO₂High, pre-sinter TiO₂The interval between the particles 3 is as shown in Fig. 17(a).₀For example, the surface of the titanium oxide particles 3 having a positive curvature has a high vapor pressure, and the surface having a negative curvature, that is, the surface of the neck where the two titanium oxide particles 3 are butted, has a low vapor pressure. As shown in Fig. 17(b), there is a SnO in the neck which has a higher vapor pressure than titanium oxide.₂The incorporation is solidified as shown in Fig. 17(c), and sintering is performed by a gasification-solidification mechanism.

Then, when sintered by a gasification-solidification mechanism, the sintered TiO₂Particle gap L₂The interval between the system and the sintering₀It's about the same, so there won't be cracks, etc.

As described above, substantially no change of TiO before and after sintering₂The particle spacing and the photoactivity of the photocatalytic film is 50% or more (R₃₀), as shown in Figure 28, for TiO₂In terms of SnO₂The mixing ratio is 20~70%.

Further, the blending ratio is expressed by the weight ratio of the fixed components contained in the sol. Further, the evaluation of photoactivity was carried out by decomposition of methyl mercaptan and removal rate after irradiation for 30 minutes by light (R).₃₀) as an indicator. Specifically, a 150 square tile in which a photocatalyst film is formed is placed in an 11 L glass container at a distance of 8 cm from the light source (4W BLB lamp), and 3 to 5 ppm of methyl mercaptan is injected to confirm that there is no darkness in the dark. After the adsorption, the fluorescent lamp was turned on, and the concentration change was measured by gas chromatography over time.

Here R₃₀=(X₀-X₃₀)/X₀×100%

Only X₀= initial concentration [ppm], X₃₀= concentration after 30 minutes [ppm].

Moreover, the evaluation of the film strength is such that the plastic wiping rubber is rubbed back and forth to compare the change in appearance. The basis of the evaluation , , , × is as described in Table 1 above.

Further, Fig. 29 shows a correlation diagram between heat treatment temperature and photoactivity, and an organic stabilizer is added to TiO.₂In the case of a sol, although the photoactivity is lowered, the heat treatment temperature is set to 300 to 850 ° C at this time. This is difficult to produce activity when the heat treatment temperature is below 300 ° C, and TiO is above 850 ° C.₂The structure will change from anatase to rutile.

As can be seen from the above description, the sol containing titanium oxide particles and a vapor pressure higher than the titanium oxide is applied to the tile, sintered at a predetermined temperature, and sintered by a gasification-solidification mechanism to form a film. Therefore, after the sintering, the intervals of the titanium oxide particles are approximately equal, and cracking is less likely to occur. Also, the neck between the titanium oxide particles will solidify the SnO₂In this case, the peel strength of the film can be improved.

Especially making SnO₂Addition amount (with TiO₂The internal ratio is 20 to 70%, which satisfies both the film strength and the photoactivity. Further, when it is heat-treated at a temperature of 300 ° C or more and 850 ° C or less, sufficient photoactivity can be obtained.

As for the determination of R by gas chromatography₃₀The method is expensive because the measuring device is expensive, and one device can only measure one sample, and the efficiency is poor.

Also, a metal such as platinum is supported on TiO₂Although it is possible to increase the photoactivity, it is a matter of conventional knowledge. However, when the photocatalyst film of the above structure is used, there is a metal adsorbing gas, and it is difficult to judge the degree of correct photoactivity.

Further, once the tile or the like is applied to the wall surface, the activity of the photocatalyst film formed on the surface thereof cannot be measured by gas chromatography.

Moreover, the method of evaluating photoactivity without using gas chromatography may be considered, and the survival rate of the bacteria after killing the cells by the photocatalyst may be considered, but this method is more complicated than the operation of gas chromatography, and The photocatalyst film carrying metal can kill bacteria only by the antibacterial force of the metal itself, and it is difficult to judge the true photoactivity. For this purpose, the following method for measuring the activity of the photocatalyst film can be applied.

The first method is to form TiO on the surface of the substrate.₂As the surface of the photocatalyst film of the main body, an aqueous solution of a halogenated alkali such as potassium iodide or potassium chloride is dropped, and then the aqueous solution of the halogenated alkali which is irradiated with ultraviolet rays is irradiated for a predetermined period of time, and the difference between the pH value of the aqueous solution of the halogenated alkali before irradiation and the pH after the irradiation is To determine the activity of the photocatalyst film.

The second method is to form TiO on the surface of the substrate.₂For the surface of the photocatalyst film of the main body, a mixed liquid of a pH indicator is added to an aqueous solution of a halogenated alkali such as potassium iodide or potassium chloride, and then the mixed liquid is irradiated with ultraviolet rays for a predetermined period of time, and the color of the mixed liquid is changed to judge the photocatalyst film. Activity.

The third method is to form TiO on the surface of the substrate.₂The surface of the photocatalyst film of the main body is adhered to the active measurement film, and in this state, the active measurement film is irradiated with ultraviolet rays for a predetermined period of time, and the activity of the photocatalyst film is judged by the color change of the activity measurement film.

Figure 30 is a view showing the first and second activity measuring methods, and the surface of the substrate 1 is formed with TiO₂The photocatalyst layer 2 is the main body. To test whether the photocatalyst layer 2 is photoactive, a halogenated alkali aqueous solution 30 such as potassium iodide or potassium chloride is dropped on the surface of the photocatalyst layer 2, and then the aqueous solution 30 of the halogenated alkali is dropped on the ultraviolet light 40 for a predetermined period of time. The difference in the pH of the aqueous solution of the halogenated alkali before the irradiation and the pH after the irradiation was judged as the activity of the photocatalyst layer 2.

Figure 33 is a graph showing the correlation between the ultraviolet irradiation time and the amount of change in the pH value, and the concentration of the aqueous alkali solution 30 is 0.1 mole/<img file="TW406031B_D0069.tif" />The ultraviolet lamp 40 was a BLB fluorescent lamp 20W, and the distance between the photocatalyst layer 2 and the ultraviolet lamp 40 was 20 cm, and the irradiation time was 60 minutes.

As can be seen from the figure, when the photocatalyst layer 2 of any of the anatase type, the metal-supported type, and the rutile type is irradiated with ultraviolet rays for 30 minutes, the pH of the aqueous alkali solution 30 is high.

Thereby, the pH of the ultraviolet-ray halogenated alkali aqueous solution 30 is increased because the oxidation reaction and the reduction reaction occur simultaneously, and the reduction reaction generates OH-(hydroxyl ions).

Oxidation reaction: 2I^-+2h⁺=I₂

Reduction reaction: O₂+2H₂O+4e^-=4OH^-

Therefore, when the pH of the aqueous alkali solution 30 is raised by ultraviolet irradiation, the photocatalyst layer 2 indicates that it is photoactive.

Figure 34 shows R₃₀Correlation diagram with the amount of change in pH. Here R₃₀The ratio (%) of the gas (methyl mercaptan, etc.) which is reduced 30 minutes after the irradiation of ultraviolet rays, and the surface is known as R.₃0 is proportional to the amount of change in pH. That is, the amount of change in pH is an indicator of the absence of photoactivity.

In the first method, the pH change amount is performed by a pH meter or a pH test piece 50, and in the second method, a mixed liquid of the halogenated alkali aqueous solution 30 to which the pH indicator is added is dropped on the surface of the photocatalyst layer 2, and then The dropped mixture was irradiated with ultraviolet light for a predetermined period of time, and the activity of the photocatalyst layer 2 was judged by the color change of the mixed solution.

The pH indicator is UV-irradiated to a pH of about 4.5 before the aqueous alkali solution 30, and the pH after ultraviolet irradiation is 5.5 to 6.5. Therefore, methyl red is preferred.

Further, in the first method and the second method, a mixed liquid of a pH indicator is added to the surface of the photocatalyst layer 2, and a liquid mixture of the pH indicator is added to the aqueous solution 30, but the liquid on the substrate is expanded on each substrate. Unlike the same, it is impossible to ensure a certain liquid thickness, and sometimes the reaction area of each substrate is different.

In order to solve this problem, there is a method shown in FIG. 31, in which the aqueous solution 30 of the halogenated alkali is added to the surface of the photocatalyst layer 2, and the aqueous solution of the halogenated alkali 30 is pressed against a transparent plate 60 such as a glass plate to maintain a certain thickness. Prevent drying.

Further, since the liquid system of the halogenated alkali aqueous solution 30 or the like is made horizontal on the surface of the substrate 1, it is difficult to judge the activity of the photocatalyst film formed by the vertical surface or the ceiling surface of the wall surface which is provided.

In order to solve this problem, the method shown in FIG. 32 can be employed. The method is such that the surface of the photocatalyst layer 2 formed on the surface of the substrate 1 is in close contact with the active measurement film 70, and in this state, ultraviolet rays are irradiated onto the active measurement film 70 to The color change of the activity measuring film 70 determines the activity level of the photocatalyst layer 2.

The activity measuring film 70 can be obtained by adding a mixed solution of a halogenated alkali aqueous solution such as potassium iodide or potassium chloride and a pH indicator to an organic binder and drying it into a film.

Next, the porosity of the photocatalyst layer 2 is examined. In terms of the porosity, the porosity is 10% or more and 40% or less, preferably 10% to 30%.

In this case, the crystal particle diameter of the photocatalyst particles is preferably 0.1 μm or less, preferably 0.04 μm or less. The smaller the crystal grain size, the larger the effective area per reaction of the reaction, so that the film thickness of the photocatalyst layer is about 0.1 μm. When the photocatalyst particles are solid-phase sintered to each other to form a neck portion, in order to increase the layer strength, the crystallite grain size is increased to 0.1 μm or more, and the effective area per unit volume is reduced, so that the film thickness is 0.5 μm or more. Preferably, it is 0.6 μm or more.

Further, a particle having a crystal grain size of 0.01 μm or less, preferably 0.008 μm or less, is added between the photocatalyst particles constituting the photocatalyst layer formed on the surface of the substrate. By adding such particles, the voids between the photocatalyst particles can be buried to increase the particle filling ratio and surface smoothness, thereby increasing the film strength against shear stress. Improve surface smoothness to reduce contamination. In this case, the porosity is lowered, but the pore diameter of the pore diameter is less than 0.01 μm, preferably preferably less than 0.008 μm, and is larger than the gas size (number Å). Therefore, it does not affect its odor resistance.

Basically, the particle size of the crystal grain size of 0.01 μm or less, preferably 0.008 μm or less, may be any. However, in addition to the voids embedded in the photocatalyst particles, the particles may partially cover the surface, so it is preferable not to affect And photocatalytic activity of TiO₂, SnO₂,ZnO,SrTiO₃, Fe₂O₃,Bi₂O₃, WO₃An oxide semiconductor or a metal such as Ag or Cu is preferred. Further, any method of adding the crystal having a crystal grain size of 0.01 μm or less, preferably 0.008 μm or less, may be employed. For example, by hydrothermal treatment or the like, the ultrafine particles as described above are formed, and then dispersed as a sol in a suitable dispersion liquid, and applied to the photocatalyst layer by a spray coating method to evaporate the organic dispersant at a low temperature heat treatment to the extent that the particles are not formed. Further, an alkoxide or an organic metal salt is applied onto the photocatalyst layer, and after heat treatment, a diluent, an organic component, or the like may be evaporated.

Further, it is also possible to fix metal particles smaller than the gap of the photocatalyst layer formed on the surface of the substrate. By fixing the metal particles, the photocatalytic activity is further enhanced by the electron trapping effect, and the odor resistance is also better than that of the photocatalyst layer alone.

Here, the type of the metal particles is any material that can capture electrons, that is, any. For example, it may be Cu, Ag, Pt or the like.

The size of the metal particles must be such that the average particle diameter is smaller than the average pore diameter of the surface of the photocatalyst layer. Further, when the average pore diameter of the surface of the photocatalyst layer is 10% to 40% of the sample observed by an electron microscope, it is approximately equal to the diameter of the photocatalyst particle, and therefore it is required to be smaller than the photocatalyst particle diameter. Preferably, the photocatalyst has a smaller particle size than the starting material. The starting material of the photocatalyst layer is usually a raw material of 0.05 μm or less, and therefore it is preferably 0.05 μm or less.

The following is a detailed description of the porosity as follows.

Example 28

By coating method, changing the coating amount, coating crystal grain size 0.01 μm TiO₂The ammonia-decomposing suspension of the sol is fired at 700 ° C to 900 ° C to form a photocatalyst layer on a 15 cm square-shaped tile substrate. Evaluation of anatase TiO for the obtained sample₂The crystal grain size of the particles, the porosity of the surface of the layer, the odor resistance, the abrasion resistance, and the peeling resistance.

Determination R₃₀(L) to evaluate the deodorant. R₃₀(L) The removal rate after light irradiation, specifically, the photocatalyst film which is placed in a glass container of 11 liters is placed at a distance of 8 cm from the light source (BLB fluorescent lamp 4W), and the initial concentration can be 3 ppm. The methyl mercaptan gas was injected into the container, and the change in concentration when the light was irradiated for 30 minutes was measured.

The abrasion resistance is rubbed back and forth using a plastic eraser, and the change in appearance is evaluated. The evaluation indicators are as described above and are shown below.

: 40 times back and forth can not change

: Sliding back and forth 10 times or more and 40 times or less, there is scratch, photocatalyst layer (TiO₂Membrane)

: Sliding back and forth 5 times or more and 10 times or less, there is scratch, photocatalyst layer (TiO₂Membrane)

×: After sliding 5 times or less, there is a scratch, and the photocatalyst layer (TiO₂Membrane)

The peeling resistance test was carried out under conditions more severe than the abrasion resistance test, and a squeegee (rough) eraser (LION TYPE WRITER ERASER 502) capable of applying a large shear force was used instead of the eraser. Specifically, the rough eraser was rubbed back and forth 20 times with equal force to visually compare the state of the standard sample and the scratch, and the standard was as follows.

: completely unchanged

: You can see a slight change by light.

: Change slightly

×: Seeing the change at a glance

The results are shown in Figures 35 to 37.

Fig. 35 is a graph showing the relationship between the porosity, the odor resistance and the abrasion resistance of the photocatalyst film having a thickness of 0.8 μm. The deodorant can be increased with the increase of porosity, 50% for 10% and 80% for 30%. On the contrary, the abrasion resistance is at 30%, at 40%, and Δ or × at higher porosity. Therefore, it can be seen from the above that when a material having both deodorant properties and abrasion resistance is to be produced, the photocatalytic film must have a porosity of 10% to 40%, preferably 10% to 30%.

Figure 36 is a diagram showing the effect of film thickness on the odor resistance when the photocatalytic particle size of the photocatalyst film constituting 20 to 30% of the porosity is changed. When the crystal grain size is 0.1 μm, the film thickness is R₃₀(L) has an effect, the thinner the deodorization. When the thickness is 0.04 μm or less, the film thickness does not affect it, and when the film thickness is 0.1 μm, the film has excellent odor resistance. From the above, it is understood that the crystal particle diameter of the photocatalyst particles is preferably 0.1 μm or less, preferably 0.04 μm or less, and a film having a film thickness of about 0.1 μm can ensure good odor resistance.

Figure 37 is a diagram showing the effect of the film thickness on the odor resistance and the peeling resistance of the photocatalyst particles which constitute the photocatalytic film having a porosity of 20 to 30%. When the mechanical strength value is required to be increased to the peeling resistance test level, the sample without the neck may become Δ or ×. It is desirable to form a mechanically sufficient neck bond by solid phase sintering of photocatalyst particles. The growth of photocatalyst particles is only 0.04 μm, which is still insufficient, and must be grown to about 0.1 μm. However, when the photocatalyst particles are grown to about 0.1 μm, the film thickness affects the odor resistance, and the thicker the film, the higher the odor resistance. Specifically, 0.5μm film thickness can make R₃₀(L) is 50% or more, and when it is 0.6 μm, it is 80% or more. From the above results, it is understood that the solid phase sintering photocatalyst particles form a neck between the particles, and when the crystal grain size is increased to 0.1 μm or more, the film strength can be sufficiently increased. In this case, by increasing the crystal grain size to 0.1 μm or more, the effective area per reaction is reduced, so the film thickness must be 0.5 μm or more, preferably 0.6 μm or more.

Example 29

TiO coated with a crystal grain size of 0.01 μm was sprayed on a 15 cm square tile substrate.₂The ammonia-gelling suspension of the sol was fired at 750 ° C to form a photocatalyst film. TiO at this stage₂Thin film porosity is 45%, TiO₂The crystal grain size of the particles was 0.02 μm. Coating SnO of different crystal grain sizes by spraying method₂The sol was dried at 110 ° C to obtain a sample. The odor resistance and abrasion resistance of the obtained sample were evaluated.

The results are shown in Figure 38, changing SnO₂The crystal grain size of the sol was from 0.0035 μm to 0.01 μm, and no change was observed in the odor resistance, and good results were obtained. In contrast, SnO is different when 30% by weight or more is added.₂The crystal grain size of the sol has different effects on the abrasion resistance. That is, when the particles of 0.008 μm or less are added, the film can be increased to or , but the effect of addition is not obtained at 0.01 μm.

From this, it is understood that when particles having a crystal grain size of 0.01 μm or less, preferably 0.008 μm or less, are added between the photocatalyst particles, the abrasion resistance can be improved.

Example 30

Change the amount of addition, spray the crystal size of 0.01μm TiO₂The ammonia-decomposing suspension of the sol was applied onto a 15 cm square-shaped tile substrate and fired at 850 ° C to form a photocatalyst film having a film thickness of 0.2 μm. Then, a copper acetate aqueous solution was applied by a spray coating method to the photocatalyst film, and then the photoreduction was carried out (the light source was a 20 W BLB lamp, the distance from the light source to the sample was 10 cm, and the irradiation time was 10 seconds). The amount of copper held at this time is 2μg/cm.², its particle size coefficient is nm~10nm. Further, the crystal particle diameter of the photocatalyst particles was 0.1 μm. The odor resistance and abrasion resistance of the obtained sample were evaluated.

Result R₃₀(L) is 89%, and the abrasion resistance is . Therefore, compared with Figure 36, because of the copper, R₃₀(L) can be significantly increased from 18% to 89%.

From the above, it is understood that a material having both a deodorizing property and a wear resistance can be provided by forming a photocatalyst film having a porosity of 10% to 40%, preferably 10% to 30%, on the surface of the substrate.

Next, an explanation will be given of an embodiment in which a void formed by a photocatalyst layer is filled with particles having a smaller void. The void referred to in this embodiment refers to both the interparticle voids and the neck recesses that are separated.

In addition, the photocatalyst layer is generally denser and has better film strength and less staining property. However, the temperature of the photocatalyst layer must be increased, and the material of the substrate is limited, and the void is further processed according to the present invention. In the method of filling the particles, the porosity of the photocatalyst layer before the addition of the particles to the void may be 10% or more. Further, the film having a porosity of 10% or more is excellent in deodorizing property, so that it is possible to provide a multifunctional material which is superior in both antifouling property and deodorizing property by appropriately adjusting the filling amount thereof.

The particles which are filled in the voids and which are smaller than the voids are preferably made of an inorganic crystalline material, and more preferably have a photocatalytic activity, and are made of TiO.₂, SnO₂,ZnO,SrTiO₃, Fe₂O₃,Bi₂O₃, WO₃An oxide semiconductor is preferred. The size of the smaller particles is substantially smaller than the average of the pore diameters generated, in view of reducing voids and reducing the adhesion of particles to the surface of the particles having photocatalytic function to improve surface smoothness and reduce surface defects. It is not easy to be contaminated, and it is preferable to use a small particle of 0.01 μm or less, preferably 0.008 μm or less, in terms of film strength and the like. TiO₂The film is anatase type, and when it is heat-treated at 850 ° C or lower to be fixed on a substrate, it is observed by an electron microscope, and its average porosity is about TiO.₂The particle diameter is equal, so it is more TiO₂The particle diameter is small. TiO with photocatalytic activity₂The starting material of the film is usually a raw material of 0.05 μm or less, and therefore preferably 0.05 μm or less.

Here, the surface porosity of the layer having the photocatalytic function of the filler particles in the void is 20% or less, that is, it is less likely to be stained. Further, the maximum width of the opening is preferably 0.04 μm or less.

The term "porosity" as used herein refers to the porosity of the surface of the substrate, and the maximum width of the opening refers to the maximum value of the gap distance between two adjacent particles in the photocatalytic-functional particles constituting the surface of the substrate (average value +3× standard deviation).

Further, if the filler particles used before the voids have a porosity of about 10% in the layer having a photocatalytic function, the porosity is reduced to 10% or less, and the porosity is crystallized. Particles below 0.01μ can enter large, larger than the gas size (number Å), so they do not affect the odor resistance, and can retain TiO equivalent to 10% or more of the porosity previously prepared.₂The film has the same deodorant properties.

Further, when the photocatalyst particles of the crystal form are used as the layer having the photocatalytic function, they do not have scale, and adhere to the solid adhered form of the glass to become dirt, and are easily wiped off even if adhered. Algae are also less likely to grow when used in a flowing water.

The photocatalyst particles referred to herein are those which are capable of detecting the maximum enthalpy peak of the crystal when the photocatalyst particles are stripped from the material by 50 KV-300 mA conditions.₂In the case of particles, the photocatalyst particles are crystallized to the extent that the anatase system 2θ=25.3, and the rutile type is 2θ=27.4).

The method of filling the particles in the above-mentioned voids can be carried out by coating, drying, and heat treatment using a metal alkoxide, an organic metal salt sulfate or the like. For example, a metal alkoxide is applied by coating a mixed metal alkoxide with a suitable diluent and a salt solution on the outermost surface of the photocatalyst layer, followed by drying and heat treatment. The appropriate diluent herein is preferably an alcohol such as ethanol, propanol or methanol, but is not limited thereto. It is best not to contain water as much as possible. When the water is in a state, the metal alkoxide is suddenly hydrolyzed, which may cause cracking. Further, hydrochloric acid is added to prevent cracking during drying or heat treatment. The method of coating the metal alkoxide is usually carried out by a casting method, but is not limited thereto. The casting system is preferably carried out in dry air. When it is applied in general air (atmosphere), it is promoted to be hydrolyzed by moisture in the air, and it is difficult to control the film thickness. It can be applied once, and it can be done several times. It can be determined by the filling properties of the photocatalyst layer before coating. Thereafter, it is left in a dry air for several minutes, and the particles are filled in the voids of the photocatalyst layer to form a film.

Here, if the layer before the application of the filler particles and the particles to be filled are made of the same material, the thermal expansion coefficient is the same, and a film having excellent mechanical strength can be formed, which is most preferable.

In addition, the case of using a titanium alkoxide is further explained by listing specific examples. In the process of applying the titanium alkoxide to the surface of the photocatalyst layer and applying the drying heat treatment, the titanium alkoxide coating amount is converted into TiO.₂When the time is 10μg/cm²Above 100μg/cm²the following. When the amount of coating is too small, the number of coatings must be increased, and the efficiency is not good. On the contrary, when the coating amount is too large, the coating once becomes a too thick film, and cracking occurs during drying or heat treatment.

In the above drying heat treatment process, the heat treatment temperature is set to 400 ° C to 800 ° C. Unshaped TiO at temperatures below 400 °C₂Uncrystallized into anatase TiO₂When it is above 800 °C, it will suddenly promote grain growth and reduce photoactivity.

Further, the amount of hydrochloric acid to the titanium alkoxide in the coating liquid is set to be 1% by weight to 10% by weight. When it is 1% by weight or less, the cracking prevention effect is not sufficient. When it is 10% by weight or more, the hydrochloric acid system is usually a 36% aqueous solution, and the moisture content is too large to promote hydrolysis and cracking. When the amount of hydrochloric acid is large, it is preferred to use more diluent. Hydrolysis can be inhibited by the diluent. The ratio is preferably hydrochloric acid (removal of water): diluent = 1:100 to 1:1000.

In addition, a layer having a photocatalytic function is formed, and a void having a smaller void is filled in a void formed on the surface of the layer, and at least one of copper, silver, zinc, iron, cobalt, nickel, palladium, platinum is fixed on the layer. metal. In this configuration, the higher adsorption site of the photocatalytic functional layer is estimated in advance by the above-mentioned metal, and in this portion, the alkali metal, calcium, etc. in the dust component are not adhered, and the photocatalytic activity is eventually lost. Therefore, the antibacterial effect of the photocatalyst is not affected, and the adhesion of the fungus can be prevented. Further, when silver, copper or zinc is used as the above metal, the metals themselves have antibacterial properties and are more effective in preventing adhesion of fungi. In addition, the photoactivity of the photocatalyst layer can be further enhanced by the electron trapping effect of the metal.

The size of the metal to be fixed is such that it can occupy a high adsorption site of the photocatalyst layer in advance, and must be small enough to maintain high activity. From this point of view, it is preferable to use about several nm to 10 nm.

The method of fixing the above metal can utilize a photoreduction method, a heat treatment method, a sputtering method, a CVD method, etc., wherein the photoreduction method can be used without a large-scale apparatus, and is relatively simple and can be firmly fixed, so that it is suitable. In the photoreduction method, an aqueous solution containing at least one metal ion in silver, copper, zinc, iron, cobalt, nickel, palladium or platinum is applied to irradiate ultraviolet rays. The aqueous solution containing at least one metal ion of silver, copper, zinc, iron, cobalt, nickel, palladium or platinum may be copper acetate, silver nitrate, copper carbonate, copper sulfate, cuprous chloride, copper chloride, chlorinated platinum acid. , palladium chloride, nickel chloride, zinc nitrate, cobalt chloride, ferrous chloride, ferric chloride, and the like. The coating method of the aqueous metal salt solution is basically any method, but the spraying method or the dip coating method is simple. The use solution can be applied in a small amount, can be uniformly applied, and the film thickness can be easily controlled, and it is suitable for spraying from the viewpoint of being freely coated when it is not desired to be applied to the back surface. The light containing ultraviolet rays can be irradiated with ultraviolet rays, specifically, any of an ultraviolet lamp, a BLB lamp, a xenon lamp, a mercury lamp, and a fluorescent lamp. The method of irradiating the ultraviolet ray-containing light is to arrange the sample so that it can be irradiated to the irradiation surface vertically. This can improve the illumination efficiency. The irradiation time is preferably about 10 seconds to 10 minutes. When the irradiation time is too short, the above-mentioned metal species cannot sufficiently adhere to the highly adsorbable portion of the photocatalyst layer, and the alkali metal or calcium in the dust component adheres to the photocatalytic activity. When the time is too long, the metal species is excessively attached. Light does not reach the photocatalyst layer sufficiently, reducing photocatalytic activity. The distance from the sample to the light source is preferably 1cm~30cm. When the distance is too close, the whole sample cannot be uniformly irradiated, and the metal species are unevenly attached. When the distance is too far, the illumination of the light will be inversely proportional to the square of the distance. It is difficult to adhere to the metal species firmly.

The following examples show that the voids formed by the photocatalyst layer are filled with particles smaller than the voids.

Example 31

TiO coated with a crystal grain size of 0.01 μm was sprayed on a 15 cm square tile substrate.₂The ammonia-gelling suspension of the sol was fired at 750 ° C to form a photocatalyst film. TiO at this stage₂Thin film porosity is 45%, TiO₂The crystal grain size of the particles was 0.02 μm. Coating SnO of different crystal grain sizes by spraying method₂The sol was dried at 110 ° C to obtain a sample. The obtained sample was evaluated for its odor resistance, abrasion resistance, and stain resistance.

Deodorant evaluation is measured R₃₀(L) to be assessed.

The abrasion resistance is rubbed back and forth using a plastic eraser, and the change in appearance is evaluated. The evaluation indicators are as described above and are shown below.

: 40 times back and forth can not change

: Sliding back and forth 10 times or more and 40 times or less, there is scratch, photocatalyst layer (TiO₂Membrane)

: Sliding back and forth 5 times or more and 10 times or less, there is scratch, photocatalyst layer (TiO₂Membrane)

×: After sliding 5 times or less, there is a scratch, and the photocatalyst layer (TiO₂Membrane)

The evaluation of the non-staining property is to draw a line on the surface of the substrate with a black thick pen. After drying, the ink is wiped with ethanol and the degree of contamination is evaluated according to the following criteria.

: Can be completely wiped off without leaving traces

: leave a little trace

: A little grayish trace

×: Leave a black mark.

The results are shown in Figures 39 to 46.

Figure 39 shows SnO₂The relationship between the added amount and the non-staining property. Here at SnO₂Addition amount to TiO₂With SnO₂The sum of the weight of the amount of SnO₂The weight ratio is expressed. Add more than 30% SnO₂It can significantly improve the stain resistance. There are three reasons for this. The first is because more than 30% of SnO is added.₂It can reduce the porosity to 20% or less (Fig. 40), and the second system is due to the addition of SnO.₂And reduce the pores with large porosity. Figure 41 shows the pair of SnO₂The maximum width of the added pores, more than 30% SnO₂The amount of addition was reduced to a small pore width of 0.04 μm. Tertiary due to the addition of SnO₂Increasing the surface roughness affects its non-stainability.

Figure 42 shows the pair of SnO₂Adding amount of odor resistance and abrasion resistance.

Regarding the deodorant aspect, make SnO₂There was almost no change in the crystallite size of the sol from 0.0035 μm to 0.01 μm, showing excellent results. Also, for SnO₂In terms of quantity, when it is less than 50%, R₃₀Has a good result of more than 80%. Compare SnO in Figure 39₂When the relationship between the amount of addition and the porosity is known, SnO₂When the amount of addition is 40% to 50%, the porosity is 10% or less, and the odor resistance is good. This is quite different from the relationship between porosity and odor resistance (Fig. 35) when no filler particles are added. The reason is presumed as follows. That is, at this time, the porosity can be reduced to 10% or less, but compared with the case of Fig. 41, there are still about 0.02 μm of pores left. Further, the particle size of the particles embedded in the void is also 0.0035 μm, which is larger than the size of the gas (the number Å), and the gas passage is not closed under the condition that the particles are not grown.

About SnO, SnO₂When the amount of addition is 30% or more, due to SnO₂The effect of the crystal grain size of the sol is different. That is, when the particles of 0.008 μm or less were added, the film was increased to or , but when 0.01 μm was added, the effect of addition was not observed.

The following facts are known from the above experiments.

(1) Forming TiO on a substrate₂Membrane, adding smaller particles (SnO) than the voids in the voids formed on the surface of the film₂In the case of sol), it is possible to improve the stain resistance.

(2) on TiO₂With SnO₂In terms of total weight, SnO₂When the amount added is 30% by weight or more, it is less likely to be stained, and the abrasion resistance can be improved.

(3) on TiO₂With SnO₂In terms of total weight, SnO₂When the amount added is 50% by weight or less, excellent odor resistance can be maintained.

(4) The porosity is 20% or less, and the widest width of the pores is 0.04 μm or less, which is less likely to be stained.

Example 32

The urinal does not illuminate the side portion of the light to form anatase TiO₂Membrane, field test for 2 weeks. And no anatase TiO₂The film is compared. The results will turn yellow due to the attachment of fungi and urinary scale. However, the general toilet is brushed and it is not easy to remove the dirt, but the side part forms anatase TiO.₂The membrane toilet is brushed to remove yellow urinary scale.

Since the side surface is not irradiated with light, it is known that it is not due to anatase TiO.₂The photocatalytic effect of the film is due to the formation of crystalline anatase TiO which is not easy to adhere to the dirt due to its surface.₂The result is obtained by the film.

Example 33

Coating SiO on the surface of a 15 cm square tile₂-A<img file="TW406031B_D0070.tif" />O₃-Na/K₂O glass, and then sprayed on the surface, crystal grain size 0.01μm TiO₂Sol-ammonia-degraded suspension, fired at 750 ° C, to obtain three 0.2μm, 0.4μm, 0.8μm film thickness of TiO₂film. TiO at this stage₂Thin film porosity is 45%, TiO₂The crystal grain size of the particles was 0.02 μm. Further, a mixture of tetraethanol titanium and 36% hydrochloric acid and ethanol was mixed by a coating method on the sample after cooling by using dry air as a carrier at 10:1:400 (by weight), and dried. Coating amount is TiO₂In terms of 40~50μg/cm². Thereafter, it was baked at 500 ° C for 10 minutes. The coating step of the titanium alkoxide is repeated 1 to 5 times. The obtained samples were evaluated for odor resistance, antibacterial property, abrasion resistance, and stain resistance.

The antibacterial strain was tested using Eschericia coli W3110 strain. 0.15m drops on the top surface of the multifunctional material sterilized with 70% ethanol in advance<img file="TW406031B_D0071.tif" />The (1~50000 CFU) bacterial solution was placed on a glass plate (100×100) and attached to the uppermost surface of the substrate as a sample. After irradiating the white lamp (3,500 candelas) for 30 minutes, wipe the irradiated sample with the sterilized gauze and collect it at 10m.<img file="TW406031B_D0072.tif" />The physiological saline solution was used to determine the survival rate of the bacteria, and the evaluation criteria +++, ++, +, - were the same as above.

Under the above conditions, the deodorant system R₃₀(L) is 80% or more, and the antibacterial property is +++.

Non-staining property (Fig. 44) and abrasion resistance (Fig. 45) are the number of coatings with titanium alkoxide and TiO₂The film thickness is related. The more the titanium alkoxide is coated, the more it is less susceptible to staining and abrasion resistance. Also, TiO₂The thinner the film thickness, the less the number of times the titanium alkoxide is coated, the less the stain resistance and the abrasion resistance. The reason can be presumed to be that TiO can be reduced by coating with titanium alkoxide.₂The porosity of the surface of the layer is one of the reasons. Figure 46 shows TiO₂Porosity of layer surface and titanium alkoxide coating times and TiO₂The relationship between film thickness. TiO₂The porosity of the surface of the layer is reduced as the number of times the titanium alkoxide is coated, and the TiO is reduced.₂The thinner the film, the less the porosity will be reduced under the same number of titanium alkoxide coatings. This relationship is related to the number of titanium alkoxide coatings and TiO.₂The film thickness corresponds to the relationship between the non-staining property and the abrasion resistance. In particular, in the case of the non-staining property, as in the case of Example 31, the porosity was 20% or less.

Example 34

Coating SiO on the surface of a 15 cm square tile₂-A<img file="TW406031B_D0073.tif" />O₃-Na/K₂O glass, and then sprayed on the surface, crystal grain size 0.01μm TiO₂The ammonia degummable suspension of the sol was fired at 750 ° C for 2 hours. TiO at this stage₂Thin film porosity is 45%, TiO₂The crystal grain size of the particles was 0.02 μm. Further, a mixture of tetraethanol titanium and 36% hydrochloric acid and ethanol was mixed by a coating method on the sample after cooling by using dry air as a carrier at 10:1:400 (by weight), and dried. Coating amount is TiO₂In terms of 40~50μg/cm². Thereafter, it was baked at 500 ° C for 10 minutes. This titanium alkoxide coating step was repeated three times. Then, a 1% by weight aqueous solution of silver nitrate was applied to the sample, and a sample was obtained by photoreduction (light source: 20 W BLB lamp, distance from the light source to the sample of 10 cm, irradiation time: 30 seconds). The amount of silver held on the surface of this sample is 0.7 μg/cm.²The silver particle size system is about 40 nm on average. The antibacterial property and the antibacterial property after long-term use were measured for the obtained sample.

The antibacterial properties after long-term use were tested as follows. First, the surface of the obtained sample was sufficiently washed with ethanol or the like, and dried at 50 °C. Next, the bath water taken from the public bath was placed in the sterilized beaker, and the sample was immersed therein for one month. Thereafter, the sample was taken out, washed with ethanol, and then the uppermost surface of the multifunctional material was sterilized with 70% ethanol. Then placed 0.15m<img file="TW406031B_D0074.tif" />(1~50000 CFU) of the coliform solution was placed on a glass plate (100×100) and adhered to the uppermost surface of the substrate as a sample. After illuminating the white light for 30 minutes (3,500 candelas), wipe the irradiated sample with the sterilized gauze and collect it at 10m.<img file="TW406031B_D0075.tif" />The physiological saline solution was used to determine the survival rate of the bacteria, and the evaluation index was the same as that of the antibacterial test of Example 3.

For the sake of comparison, the sample of Example 33 was also tested.

As a result, in the initial antibacterial property, the sample prepared in this example was also +++ as in the sample prepared in Example 33. But after one month, the antibacterial properties of the two are different. That is, the sample prepared in Example 33 was reduced in antibacterial property to +, and the sample prepared in this example was maintained at the initial +++. This may be TiO₂Silver is adhered to the highly adsorbable portion on the surface of the layer, and it is possible to prevent adhesion of dust or the like to a highly adsorbed portion during use.

As is apparent from the above description, a layer having a photocatalytic function is formed on the surface of the substrate, and the voids formed on the surface of the layer are filled with smaller particles than the voids. Therefore, the amount of voids present on the surface and the voids thereof are higher than those of the conventional photocatalyst film. The size is small, and the smoothness of the surface is better, the good odor resistance can be maintained, the film strength is improved under the antibacterial property, and it is difficult to adhere to the polymer, dust, fungi and the like which constitute the dirt component.

Next, an example of using soda glass having a lower melting point material as a substrate will be described. That is, when a photocatalyst film is to be formed on the surface of the low-melting-point substrate, the substrate begins to soften at the temperature at which the photo-contact film is formed, and the photocatalyst film formed is buried in the substrate, so that light cannot reach the photocatalyst layer. Defects such as photocatalytic function cannot be utilized.

For this reason, in this case, the photocatalyst particles are fixed by coating a layer having a higher melting point than the substrate by coating SiO or the like. The embodiments are specifically described below.

Example 35

The cerium oxide coating is applied to the surface of the soda glass before the titanium oxide is applied to the soda glass.

On the surface of a 10 cm square sodium glass, cerium oxide was applied in the following manner. Tetraethoxydecane, 36% hydrochloric acid, pure water, and ethanol were mixed at a weight ratio of 6:2:6:86. It will be hot at this time, so put it for 1 hour. It is then applied to soda glass.

Next, a coating liquid was prepared. The coating liquid was prepared by mixing a solution of titanium tetraethoxide and ethanol at a ratio of 1:9 by weight, and adding 10% by weight of 36% hydrochloric acid to titanium tetraethoxide. The amount of 36% hydrochloric acid added thereto is preferably from 1% by weight to 30% by weight, preferably from 5% by weight to 20% by weight on the titanium tetraethoxide. When an appropriate amount of hydrochloric acid is added, it is possible to prevent drying in the post-engineering process and cracking during firing. That is, when the amount of hydrochloric acid is too small, cracking cannot be sufficiently prevented. When the amount of hydrochloric acid is too large, the water content in the hydrochloric acid reagent is increased, and the hydrolysis of titanium tetraethoxide is accelerated, and it is difficult to obtain a homogeneous coating film.

Next, the solution is applied to the surface of the soda glass substrate in dry air. The dry air referred to herein is not the air which is completely free of moisture, and refers to the case where the water content is less than that of ordinary air. At this time, if it is applied in the general air which is not subjected to the drying treatment, the titanium tetraethoxide is accelerated by the moisture in the air, and when the amount of the coating film is too large, it is easy to dry in the subsequent process. It is cracked at the time. Also, it is difficult to control the amount of coating film when accelerating hydrolysis. In order to prevent cracking, the amount of titanium oxide supported at one time is 100 μg/cm.²The following is appropriate. The amount of titanium oxide held here is 45μg/cm.²。

Thereafter, it is dried in dry air for 1 to 10 minutes to form a titanium oxide film. At this step, titanium oxide can be formed according to the following principle. Here, the starting material is titanium tetraethoxide which is one of titanium alkoxides (the titanium oxide can also be formed by the same principle using other titanium alkoxides). Mainly for the pouring, the titanium tetraethoxide causes a hydrolysis reaction with water in the dry air to form a titanium hydroxide compound. Further, a dehydration condensation reaction occurs during drying to form amorphous titanium oxide on the substrate. The titanium oxide particles produced at this time are high in purity of about 3 to 15 nm, and this titanium oxide can be sintered at a low temperature as compared with the titanium oxide obtained by other production methods.

The composite material obtained in the above method is fired at 300 ° C ~ 500 ° C, a more functional material. The thick titanium oxide is obtained by repeating the step from the coating of titanium tetraethoxide to the firing.

The odor-removing property, the abrasion resistance, and the antibacterial property of the sample thus obtained were evaluated. The results are shown in Table 19.

<tables><img file="TW406031B_D0076.tif" /></tables>

The deodorant property was that the sample was placed in a cylindrical container having a diameter of 26 cm and a height of 21 cm adjusted to an initial concentration of methyl mercaptan, and a 4W BLB fluorescent lamp was irradiated from a light source of 8 cm, and methyl mercaptan removal was measured after 30 minutes of irradiation. Rate (R₃₀(L)), and the methyl mercaptan removal rate of the light for 30 minutes (R₃₀(D)), to be assessed.

The antibacterial properties were tested using Escherichia coli W3110 strain. 0.15m of the top surface of the multifunctional material sterilized with 70% ethanol in advance<img file="TW406031B_D0077.tif" />The bacterial solution (1~50000 CFU) was placed on a glass plate (100×100) and adhered to the uppermost surface of the substrate as a sample. After illuminating the white lamp (5,200 candelas) for 30 minutes, the irradiated sample was wiped with the sterilized gauze and the sample liquid kept under the light-shielding condition was collected and collected in 10 m.<img file="TW406031B_D0078.tif" />Physiological saline, to obtain the survival rate of bacteria, as an evaluation index, +++, ++, +, - is the same as above.

Sliding test at 300 ° C firing temperature is excellent result, but R₃₀(L) is 0%. This may be due to the fact that the amorphous titanium oxide is not crystallized into anatase.

In the synthesis experiment, the temperature of the anatase was confirmed by X-ray at 400 ° C, and the sliding test also had good results of , but R₃₀(L) can also be increased to about 60%. Also, the antibacterial property may be +. Also, the sliding test result of can be obtained at 500 ° C, but R₃₀(L) can also be increased to about 60%.

Further, when the temperature was raised, deformation of the soda glass substrate was caused at 550 ° C, and it was not possible to manufacture a multifunctional material.

Example 36

In order to further improve the photocatalytic characteristics of the sample obtained in Example 35, metal particles were carried. The photocatalyst is simultaneously subjected to a reduction reaction with an oxidation reaction. If the reduction reaction is not carried out, the electrons are not consumed and the particles are charged, and the oxidation reaction cannot be performed. R in Embodiment 1₃₀(L) Only at 60% may be the reason for this. In order to prevent this from happening, metal particles are carried on the titanium oxide particles to remove electrons to prevent charging.

The metal particles can be carried in the following manner. The solution of the metal salt was applied to the photocatalyst and irradiated for 20 minutes at 20 cm from a 20 W BLB fluorescent lamp. The metal salt solution used a 1 wt% ethanol solution of copper acetate when carrying copper, and a 1 wt% ethanol/water = 1/1 mixed solution of silver nitrate when silver was used. Wash after irradiation and dry. Here, the use of the aqueous solution of the metal salt without using the aqueous solution of the metal salt is preferred because of the wetness of the sample due to the aqueous solution of the metal salt.

The odor-removing property, the abrasion resistance property, and the antibacterial property of the sample obtained above were evaluated. The results are shown in Table 20. Further, the firing temperature was obtained by using only the sample obtained at 500 °C.

<tables><img file="TW406031B_D0079.tif" /></tables>

The sliding test showed good results. Also, R₃₀The (L) line was significantly increased to 98%. Antibacterial properties are also +++.

Comparative Example 37

In Example 35, the same was true except that the cerium oxide coating was not applied. That is, titanium oxide was applied to 10 cm square sodium glass. The results are shown in Table 21.

<tables><img file="TW406031B_D0080.tif" /></tables>

It can be seen from Table 21 that 300 ° C, 400 ° C, and 500 ° C all have good results in the sliding test, and R₃₀(L) is 0% even if the titanium tetraethoxide coating film is repeated 10 times to the firing step. Moreover, the antibacterial system is one.

Why R at 300 °C₃₀(L) is not good, it may be that titanium oxide is still unable to crystallize into amorphous anatase from amorphous titanium oxide.

As for 400 ° C, 500 ° C should have been crystallized from amorphous titanium oxide to anatase, can not explain R for the above reasons₃₀(L) is not good. The reason for this is that the soda glass of the substrate is softened, so that the titanium oxide film is buried in the glass.

As apparent from the above description, even in the case of a substrate having a lower melting point, a high melting point layer may be interposed between the photocatalyst layers to produce a multifunctional material having deodorant and antibacterial properties.

Next, a description will be given of a preferred embodiment in which the surface of the plastic having poor heat resistance has a photocatalytic effect.

Basically, the material of the substrate is not limited to a plastic having poor heat resistance, and may be a ceramic, ceramic, metal, glass or the like.

The shape of the substrate may be any shape, and may be a simple shape such as a ball, a cylinder, a cylinder or a tile, a wall material, a floor plate, or the like, or a sanitary ceramic, a wash table. , complex shapes such as baths, sinks, toilet seats, etc. Further, the surface of the substrate may be porous or dense.

The type of the binder may be a thermoplastic material such as an inorganic glass, a thermoplastic resin or a solder, or a thermosetting material such as a fluorine resin, a siloxane resin or a ruthenium resin. However, in the post-engineering, it is necessary to irradiate the light containing ultraviolet rays, so it is still suitable for light-corrosive materials. Further, when it is only heat-treated at a temperature of 300 ° C or lower, since the usefulness of the present invention is extremely high, the thermoplastic material is preferably a material which can be softened at 300 ° C or lower, and the thermosetting material is preferably a material which is hardenable at 300 ° C or lower. The material which can satisfy the above conditions is a boric acid-based glass material, a solder, an acrylic resin, or the like, and a thermosetting material includes a fluorine-containing resin, a siloxane resin, a ruthenium resin, or the like.

A method of applying such an adhesive layer to a substrate may be a spray coating method, a roll coating method, a dip coating method, or the like, and any of the methods may be employed. It can also be a method other than it. Further, the binder component does not necessarily coincide with the binder composition when the material is formed. For example, when the binder is made of inorganic vitreous, the coating material may be a suspension of an inorganic vitreous composition such as a granule, a glassy material, a lump, or a powder, or may be a salt containing a metal component. Mixed. When the binder is a resin, a resin solution of the composition may be used, or other components may be used.

Before applying the photocatalyst particles to the binder layer, the applied binder layer may be dried to evaporate water or the like. In this case, the drying method may be carried out at room temperature, or may be a method of heating with a substrate.

Moreover, before applying the photocatalyst particles to the binder layer, the substrate may be softened at a lower temperature than the substrate coated with the binder, and the adhesive layer may be changed to the binder composition at the completion of the product, and may also be softened. The temperature is heat treated. According to this method, when the photocatalyst particles are formed on the binder layer, the binder layer can be made smoother, and a small amount of the photocatalyst particles can be applied to sufficiently exert the effect.

A method of applying a thermosetting material and a binder and a curing agent to the substrate may be, for example, adding a diluent to the thermosetting resin, followed by adding a curing agent, and applying the resulting mixture to the surface of the substrate.

The viscosity of the thickening is preferably from 105 poise to more than 1075 poise. The photocatalyst particles can be embedded in the high viscosity of 105 poise or more, so that the photocatalyst particles can be buried so as not to be completely buried in the binder layer, and at least 1075 poise, the photocatalyst particle layer can be at least the most A portion of the next layer is buried in the lower layer of the adhesive.

The method of applying the photocatalyst particles to the surface of the binder layer may basically employ a method of coating a suitably treated starting material on the binder layer.

The starting material is preferably a sol suspension of a photocatalyst-constituting substance, and other photocatalysts may be used to constitute a suspension of fine particles. In order to obtain a uniform coating film, any method must add a surface treating agent such as a dispersing agent so that the photocatalyst composition in the suspension does not agglomerate. When applied to the adhesive layer, a spray method, a roll coating method, a dip coating method, or the like may be used, and any other method may be employed.

The thickness of the photocatalyst layer embedded in the binder layer is preferably 1/4 or more of the thickness of the photocatalyst layer buried in the bonding strength between the photocatalyst layer and the substrate. The thickness of the photocatalyst layer can be determined by analyzing the composition of the photocatalyst particles in the cross-sectional direction by EPMA or the like, and the amount of the constituent elements constituting the photocatalyst particles is approximately equal to the upper layer portion, and the amount of the constituent elements from the photocatalytic particles is gradually started. The depth is reduced until the amount of constituent elements constituting the binder begins to form a certain amount of depth between the embedded portions.

The surface treatment agent attached to the photocatalyst is mainly formed by adding a component used as a sol which is a starting material for dispersing the photocatalyst particles. Specifically, it may be isoamyl alcohol, trimethylolpropane, triethanolamine, trimethylolamine, anthracene resin, alkylchlorodecane or the like.

Contains 1.7m W/cm²The light of the wavelength below 390 nm is used as the light source, and may be a BLB fluorescent lamp, an ultraviolet lamp, a germicidal lamp, a xenon lamp, a mercury lamp or the like. Must contain 1.7m W/cm²The reason for the above light having a wavelength of 390 nm or less is that the dispersant component such as a ruthenium resin contains a certain degree of light corrosion resistance, and therefore it is necessary to decompose the ultraviolet ray intensity to such an extent. At this time, the shorter the wavelength of the ultraviolet light, the faster the dispersing agent can be decomposed, but sometimes the binder is decomposed due to the type of the binder, and is also harmful to the human body. Therefore, it is advisable to use 250 nm or more. Also, the illumination is 3m W/cm²When it is left and right, the decomposition speed can be accelerated by the increase of illumination, but the increase of illumination will not increase the decomposition speed relatively, so 3m W/cm²The following can be.

The above steps are shown in the mode in Fig. 47. The lower portion of the substrate 1 having the photocatalyst layer 2 via the adhesive layer 6 is embedded in the adhesive layer 6. 6a is a layer formed by a surface treatment agent or the like which inhibits photocatalytic activity. UV system contains 1.7m W/cm²Light above the wavelength of light below 390 nm.

Next, a case where the photocatalyst particles 3 and the thermosetting resin 6 are mainly formed on the surface of the substrate, and ultraviolet rays are irradiated in the same manner to expose the photocatalyst layer will be described (see Fig. 48). This method also firmly fixes the photocatalyst particles 3 on the substrate by a thermosetting resin and contains 1.7 mW/cm by irradiation.²The light of the light having a wavelength of 390 nm or less emits a photocatalytic reaction on the light-irradiated portion of the surface of the photocatalyst particle, and the surface-hardener and the thermosetting resin in the direction of the light source are preferentially decomposed and vaporized to expose the photocatalyst particle to the outside air. A full photocatalytic activity is obtained.

Further, a method of forming a layer mainly by photocatalyst particles and a thermosetting resin is formed, and for example, a thermosetting resin, a diluent, and a curing agent may be sequentially added to a photocatalyst sol suspension which is sufficiently dispersed, and the resulting mixture may be applied thereto. The surface of the substrate is formed by heat treatment.

Here, the sol in the photocatalyst sol suspension preferably has a crystal grain size of 0.05 μm or less, more preferably 0.01 μm or less. The smaller the crystal grain size, the higher the photocatalytic activity. Further, the sol in the photocatalyst sol suspension is preferably as monodispersed as possible. The better the dispersibility, the more uniform the coating film can be obtained.

The thermosetting resin used herein is preferably one which has light corrosion resistance to white light or general fluorescent light horizontal light. This resin is more resistant to use when in use. Therefore, a fluorinated resin is preferred as the fluorinated resin.

The diluent can reduce the viscosity of the mixed solution of the photocatalyst sol and the thermosetting resin, and the mixture can be more easily applied to the surface of the substrate to be added. Therefore, the diluent to be used is basically a solvent which can achieve this purpose. For example, water, ethanol, propanol or the like can be used.

The coating method of the mixed solution may be the above-described spraying method, dip coating method, roll coating method, spin coating method, any of them, or other methods.

The heat treatment is usually carried out using an electric furnace, a gas furnace, a vacuum furnace, a pressurized furnace, etc., but is not limited thereto.

A layer mainly composed of photocatalyst particles and a thermosetting resin can be formed on the surface of the substrate via a thermosetting resin or a photocurable resin layer (intermediate layer C) (see Fig. 49).

According to this method, even if the substrate has irregularities or the like, a thermosetting resin layer or a photocurable resin layer disposed between the substrate and the photocatalyst layer can form a smooth surface before coating the photocatalyst layer. It is easy to form a uniform photocatalyst layer. In addition, the thermosetting resin layer or the photocurable resin layer disposed between the substrate and the photocatalyst layer can be sufficiently bonded to the substrate. Therefore, even if the surface of the substrate has irregularities, the photocatalyst can be formed thinly. The particles are layered with the thermosetting resin, and at the same time, the photocatalyst particles can be concentrated near the surface of the substrate, and the irradiation of the substrate can be further shortened by 1.7 m.

W/cm²The time of the following wavelengths of light below 390 nm. In addition, since the photocatalyst particles and the thermosetting resin are layered on the surface, the ultraviolet rays having sufficient strength to be decomposed and used at the time of use do not reach the thermosetting resin layer or the photocurable resin layer disposed therebetween. Therefore, this part of the thermosetting resin can be arbitrarily selected. For example, an inexpensive epoxy resin can be selected in conjunction with low cost, and a decorative resin can also be selected as a decorative resin.

Here, in the method of forming the thermosetting resin layer disposed between the substrate and the photocatalyst layer, a diluent may be added to the thermosetting resin, followed by addition of a curing agent, and the resulting mixed solution may be applied to the surface of the substrate. It is formed by heat treatment or placing to cure. Further, when the layer disposed in the middle of the photocatalyst layer is a photocurable resin, the ultraviolet ray-containing light can be irradiated instead of the heat treatment. In this diluent, the viscosity of the mixture can be lowered, and the mixture can be easily applied to the surface of the substrate to be added. Therefore, the diluent to be used is basically a solvent which can achieve this purpose. For example, water, ethanol, propanol or the like can be used.

Further, as shown in Fig. 50 (a) and (b), the voids formed in the photocatalyst layer exposed on the surface of the substrate by the above method may be filled with particles smaller than the voids (void particles: 4). Wear resistance is more ideal.

Particles smaller than the voids, the size of which is substantially smaller than the average value of the porosity or unevenness generated, and the amount of particles smaller than the voids is preferably such that the porosity added to the surface can be less than 20%. By this, it is not easy to stain.

Specific embodiments are given below.

Example 38

On the surface of a 10 cm square alumina substrate, 10 wt% of a naphthenic resin and a diluent, a hardener, were sequentially applied to a titanium oxide sol having an average particle diameter of 0.01 μm (dispersed by an amine dispersant). The resulting mixture was fired at 150 ° C to obtain a comparative sample. The sample was irradiated with various light sources for a predetermined period of time, and a sample was obtained to evaluate the deodorizing property of the obtained sample under light irradiation.₃₀(L).

Deodorant property R as referred to herein as light irradiation₃₀(L) means that the sample surface is placed 8 cm away from the light source (BLB fluorescent lamp 4W) in a glass container of 11 liters, and methyl mercaptan gas is injected to have an initial concentration of 3 ppm, and the concentration change rate after 30 minutes of irradiation.

The results are shown in Table 22.

<tables><img file="TW406031B_D0081.tif" /></tables>

As a result, the ultraviolet ray intensity was 1.69 m W/cm.²Above the deodorant characteristics can reach more than 50%, 2m W/cm²Deodorizing property R above₃₀(L) can be a good effect of 70% or more. Here the UV intensity is 1.69m W/cm²The above results are good because the photocatalytic reaction occurs in the light-irradiated portion of the surface of the photocatalyst particles, and the surface-hardening agent and the thermosetting resin in the direction of the light source are preferentially decomposed and vaporized to expose the photocatalyst particles to the outside air. A full photocatalytic activity is obtained.

Example 39

Applying a solution of a diluent and a hardener to the surface of a 10 cm square alumina substrate and drying it at room temperature for about 6 hours, and coating it on a titanium oxide sol having an average particle diameter of 0.01 μm. In the dispersant dispersion treatment, a mixture of 10% by weight of a decyl alkane resin and a diluent and a curing agent was sequentially added, and the mixture was fired at 150 ° C to obtain a comparative sample. The sample was irradiated with various light sources for a predetermined period of time, and a sample was obtained to evaluate the deodorizing property of the obtained sample under light irradiation.₃₀(L).

The results are shown in Table 23.

<tables><img file="TW406031B_D0082.tif" /></tables>

As a result, the ultraviolet ray intensity was 1.69 m W/cm.²Above the deodorant characteristics can reach more than 50%, 2m W/cm²Deodorizing property R above₃₀(L) can be a good effect of 70% or more. Here the UV intensity is 1.69m W/cm²The above results are good because the photocatalytic reaction occurs on the surface of the photocatalyst particles, whereby the photocatalytic reaction can be preferentially decomposed, and the vaporization cannot be vaporized by the heat treatment, and the surface of the decomposed photocatalyst particles adheres to the surface of the light-irradiated surface. The treatment agent can cause the photocatalyst particles to be exposed to the outside air.

Example 40

Applying a solution of a diluent and a hardener to the surface of a 10 cm square alumina substrate and drying it at room temperature for about 6 hours, and coating it on a titanium oxide sol having an average particle diameter of 0.01 μm. In the dispersion dispersing treatment, a mixture of 10% by weight of a decyl alkane resin and a diluent and a curing agent was sequentially added and fired at 150 ° C. At this stage, the particle gaps on the surface of the material are on average about 0.1 to 0.2 μm. Its UV intensity is 2m W/cm²Light (UV light) confirms R after 3 days₃₀After (L) is 80% or more, a cerium oxide sol having an average particle diameter of 0.0035 μm which is 70% by weight to the titanium oxide sol is applied to the surface, and the sample is dried at 110 ° C. This sample also has R₃₀(L) is a good result of 81%. Further, when the sliding friction test was carried out using a plastic eraser, the sample containing no cerium oxide was scratched five times or less, and the titanium oxide was peeled off, and the sample to which cerium oxide was added did not change even if it was slid 10 times or more. From the above, it was confirmed that when the voids formed on the surface of the material were filled with cerium oxide particles smaller than the voids, it was confirmed that the abrasion resistance was improved.

As apparent from the above description, even when a layer having a photocatalytic action which is treated at a low temperature of 300 ° C or lower is formed, a material having good photocatalytic activity can be provided.

Next, the description will be made in the same manner as the irradiation of UV to expose it, but a different means may also provide a method of firing at a low temperature of 300 ° C or lower, or a multifunctional material having a sufficient photocatalytic action.

In this method, metal fine particles are fixed on the surface of the titanium oxide sol before the addition of a dispersant, a surfactant, or the like to a titanium oxide sol by a hydrothermal method or a sulfuric acid method.

Here, the metal fine particles refer to metal fine particles capable of trapping electrons when the titanium oxide is irradiated with light to generate electrons and a positive hole, and specifically, silver, copper, platinum, palladium, nickel, iron, cobalt, etc. .

The method of fixing the metal particles on the surface of the titanium oxide sol is the easiest to use the photoreduction method. The titanium oxide sol used herein is preferably produced by a hydrothermal method or a sulfuric acid method, but is not limited thereto. The sulfuric acid method referred to herein is a method for synthesizing titanium oxide by the following procedure.

First, the ilmenite is reacted with sulfuric acid to make titanium, iron, etc. into a soluble aqueous sulfate, and water is used as a main component of titanium and iron sulfate solution. Second, remove SiO₂Insoluble suspensions. Then, it was cooled to 10 to 15 ° C, and iron sulfate was precipitated and separated. Next, the titanium oxysulfate in the solution is hydrolyzed to form a hydrous titanium oxide. The obtained hydrous titanium oxide is hydrothermally treated in a high-temperature high-pressure water (generally at a saturated vapor pressure of 110 ° C to 200 ° C) using a pressure device such as a hot press to obtain a crystal of titanium oxide.

Further, the hydrothermal method refers to hydrothermal treatment of a titanium source such as titanium tetrachloride or titanium sulfate in a high-temperature and high-pressure water (usually at a saturated vapor pressure of 110 ° C to 200 ° C) using a pressure device such as a hot press. A method of titanium oxide sol. The method of fixing the metal fine particles to the surface of the titanium oxide sol by a photoreduction method can be specifically as shown in the following.

First, the titanium oxide sol suspension prepared by hydrothermal method or sulfuric acid method is made acidic or alkaline. The isoelectric point of titanium oxide is pH 6.5, and it tends to aggregate when it is neutral. Further, it is preferred to use ammonia when it is desired to adjust to alkaline. Alkali metals such as sodium and potassium are easily adhered to titanium oxide. If these metals first occupy the active sites of titanium oxide, they will reduce the photocatalytic activity and hinder silver, copper, platinum, palladium, nickel, iron, cobalt, etc. Attached to the active site of titanium oxide.

Next, the metal salt solution having the same pH value as that of the titanium oxide sol suspension is mixed with the titanium oxide agglomerate suspension, and the ultraviolet light is irradiated to fix the metal. Excess metal can also be precipitated and removed from the solution as needed. The term "metal salt solution" as used herein refers to a salt or a solvent which, when supported in titanium oxide, is a metal which can be trapped when a titanium oxide is irradiated with light to generate electrons and a positive hole, and more specifically means silver. A solution of a salt of copper, platinum, palladium, nickel, iron, cobalt or the like with a solvent. Salts containing silver, copper, platinum, palladium, nickel, iron, cobalt, etc. may be silver nitrate, copper acetate, copper carbonate, copper sulfate, cuprous chloride, copper chloride, chloroplatinic acid, palladium chloride, chlorination Nickel, cobalt chloride, ferrous chloride, ferric chloride, etc. Further, the solvent may be water, ethanol, propanol or the like, but it is preferred to use the same type as the titanium oxide sol suspension. A pH adjuster is added to the solvent as needed. The agent adjusted to be acidic may be nitric acid, sulfuric acid, hydrochloric acid or the like, and ammonia may be used when it is adjusted to be alkaline.

Attention should be paid to the following points when irradiating ultraviolet light. First, the light source may be any one that emits ultraviolet light, specifically, an ultraviolet lamp, a BLB lamp, a xenon lamp, a mercury lamp, a fluorescent lamp, or the like. Basically, the method of irradiating the light containing ultraviolet rays is not limited, but the first is preferably irradiated from above the container. Ultraviolet light is not absorbed by the container. The distance between the second-system light source and the container is preferably from several cm to several 10 cm. When the sample solution is too close, the heat generated by the light source becomes dry, and when it is too far, the illumination is lowered. The irradiation time varies depending on the illuminance of the light source, and the metal can be firmly adhered to the photocatalyst particles by irradiation for several seconds to several tens of seconds.

Next, a film formed by coating the surface of the substrate and heat-treating the titanium oxide sol carrying the metal is formed into a multifunctional material having a photocatalytic action.

The heat treatment is usually performed by using an electric furnace or a gas kiln equal to firing in the atmosphere or using a hydrothermal treatment such as a hot press, but is not limited thereto.

The titanium oxide particles in the titanium oxide film obtained by the above method preferably have an average particle diameter of 1 μm or less. Particles larger than this will reduce catalyst activity due to reduced specific surface area.

Further, a film formed by heat treatment of the sol coating of the first application of the patent application is formed on the surface of the substrate by an adhesive to prepare a material having a photocatalytic action. When the binder is deposited, the adhesion to the substrate can be further improved. The specific method differs depending on whether the binder is a thermoplastic binder or a thermosetting binder. In the following, each of the embodiments is shown, but any other method may be employed as long as it is configured as described above. The thermoplastic binder referred to herein may specifically be an acrylic resin, an inorganic glass such as a glaze, or a solder. Further, the thermosetting binder may be a fluorine-containing resin, an epoxy resin, a decane resin or the like.

When a thermoplastic binder is used, a material having a photocatalytic action is produced by the following procedure. The thermoplastic binder is first applied to the surface of the substrate. Next, a titanium oxide sol carrying metal particles is coated thereon and heat-treated. The heat treatment is carried out at a temperature lower than the heat resistance temperature of the substrate and higher than the softening point of the thermoplastic binder. When heat-treated at such a temperature, a portion of the titanium oxide layer carrying a part of the metal particles is buried in the binder layer, whereby the substrate and the titanium oxide film carrying the metal particles are firmly bonded.

Further, when a thermosetting adhesive is used, a material having a photocatalytic action can be produced by the following procedure. First, a diluent is added to the substrate by applying a thermosetting binder, and the mixture prepared by the curing agent is cured by heat treatment or the like. Next, a mixture of a thermosetting agent resin, a diluent, and a curing agent is sequentially added to the titanium oxide sol on which the metal particles are supported, and is hardened by a heat treatment method.

Further, a photocurable binder can be similarly used instead of the thermosetting binder.

As described above, a metal such as silver, copper, platinum, palladium, nickel, iron or cobalt is fixed to the titanium oxide sol produced by a hydrothermal method or a sulfuric acid method, such as a dispersing agent or a surfactant such as a surfactant. Particles in TiO₂On the surface of the sol, since the active part of the titanium oxide sol can be covered with metal particles such as silver, copper, platinum, palladium, nickel, iron, cobalt, etc., even if a dispersant is added in the post-engineering, a surface treatment agent such as a surfactant is also Therefore, the substance is not adsorbed on the active portion of the titanium oxide sol and loses its activity. Therefore, the photocatalyst sol can be stably dispersed by the action of a surface treating agent such as a dispersing agent or a surfactant, and a uniform film can be formed on the surface of the substrate, and the dispersing agent can be prevented even at a low temperature of 300 ° C or lower. A surface treatment agent such as an active agent adheres to an active portion of the photocatalyst particle layer formed on the surface of the substrate to reduce photocatalytic action, and at the same time, a metal such as silver, copper, platinum, palladium, nickel, iron, cobalt or the like on the active portion of the titanium oxide sol The electron capture effect of the particles enhances photocatalytic activity.

The following specific implementations are as follows.

Example 41

In the autoclave, a liquid obtained by adding water in a cold bath to a titanium tetrahydrate hydrolyzed at 140 ° C to obtain an anatase type titanium oxide sol. The obtained anatase-type titanium oxide sol was dispersed in nitric acid, and the pH of the dispersion was 0.8. To the dispersion was added a 3 to 5 wt% aqueous solution of copper sulfate having a pH of about 0.8, and ultraviolet rays were irradiated from above the container. At this time, the light source was irradiated with a 4W BLB lamp at a distance of about 10 cm for 15 minutes. An organic acetate is added to the solution to form a dispersing agent, and the sol is stabilized, and the odor-eliminating property of the obtained sample is measured.₃₀(L) and antibacterial properties.

Deodorant property R when light is irradiated₃₀(L) In a glass container of 11 liters, a sample surface was placed 8 cm away from a light source (BLB fluorescent lamp 4W), and methyl mercaptan gas was injected to have an initial concentration of 3 ppm, and the concentration change rate after 30 minutes of light irradiation was performed.

Further, the antibacterial property was tested using Escherichia coli W3110 strain. 0.15m of the top surface of the multifunctional material sterilized with 70% ethanol in advance<img file="TW406031B_D0083.tif" />The bacterial solution (10000~50000 CFU) was placed on a glass plate (100×100) and adhered to the uppermost surface of the substrate as a sample. After illuminating the white lamp (5,200 candelas) for 30 minutes, the irradiated sample was wiped with the sterilized gauze and the sample liquid kept under the light-shielding condition was collected and collected in 10 m.<img file="TW406031B_D0084.tif" />Physiological saline, to obtain the survival rate of bacteria, as an evaluation index, +++, ++, +, - is the same as above.

Result R₃₀(L) is 85%, and the antibacterial system is +++, which has excellent results.

Comparative Example 42

In the autoclave, a liquid obtained by adding water in a cold bath to a titanium tetrahydrate hydrolyzed at 140 ° C to obtain an anatase type titanium oxide sol. The obtained anatase-type titanium oxide sol was dispersed in nitric acid, and the pH of the dispersion was 0.8. A dispersing agent made of an organic acetate is added to the solution to stabilize the sol. The sol was applied onto a 15 cm square tile substrate, and heat-treated at 150 ° C to obtain a sample. Deodorizing property R when measuring the irradiation light of the obtained sample₃₀(L) and antibacterial properties.

Result R₃₀(L) is 5%, antibacterial system - and the results are not good.

Example 43

In the autoclave, a liquid obtained by adding water in a cold bath to a titanium tetrahydrate hydrolyzed at 140 ° C to obtain an anatase type titanium oxide sol. The obtained anatase-type titanium oxide sol was dispersed in nitric acid, and the pH of the dispersion was 0.8. To the dispersion was added a 3 to 5 wt% aqueous solution of copper sulfate having a pH of about 0.8, and ultraviolet rays were irradiated from above the container. At this time, the light source was irradiated with a 4W BLB lamp at a distance of about 10 cm for 15 minutes. In this solution, an organic acetate is added as a dispersing agent to stabilize the sol, and then a surface of a 10 cm square alumina substrate is coated with a propanol and a hardener which are previously added with a diluent in a decyl alkane resin. The liquid is dried on a material which is dried at 100 ° C, and then a mixture of a titanium oxide resin having a titanium oxide content of 20% by weight, a propanol and a hardener is sequentially added to the sol prepared by the above method, at 150 The sample was fired at °C. Deodorizing property R when measuring light irradiation of the obtained sample₃₀(L). Result R₃₀(L) is 80%, with excellent results.

Comparative Example 44

In the autoclave, a liquid obtained by adding water in a cold bath to a titanium tetrahydrate hydrolyzed at 140 ° C to obtain an anatase type titanium oxide sol. The obtained anatase-type titanium oxide sol was dispersed in nitric acid, and the pH of the dispersion was 0.8. An organic acetate is added to the solution to form a dispersant stabilizer sol. Next, a surface of a 10 cm square alumina substrate is coated with a propanol and a hardener which are previously added with a diluent in a decane resin, and the mixture is dried at 100 ° C, and then coated. In the sol produced by the above method, a mixture of a titanium oxide resin having a titanium oxide amount of 20% by weight, a propanol and a curing agent was added in this order, and the mixture was fired at 150 ° C to obtain a sample. Deodorizing property R when measuring light irradiation of the obtained sample₃₀(L). Result R₃₀(L) is 22%, and its effect is not good.

As described above, in the titanium oxide sol produced by a hydrothermal method or a sulfuric acid method, silver, copper, platinum, palladium, nickel, iron, and cobalt are fixed before the surface treatment agent such as a dispersant or a surfactant is added. When the metal particles are on the surface of the titanium oxide sol, the substrate may be fired at a low temperature of 300 ° C or lower, such as a plastic material, to obtain a material having a sufficient photocatalytic action.

The above examples mainly describe anatase TiO₂The following describes the rutile TiO₂。

Figure 51 shows the use of rutile TiO₂A flow chart of the steps for manufacturing a multifunctional material. The invention firstly forms rutile TiO on the surface of a substrate such as a tile.₂film. Rutile TiO₂The method of film can use TiO₂The sol titanium alkoxide, titanium sulfate, and titanium chloride solution are used as a raw material, coated on a substrate, and then subjected to heat treatment or the like.

Using TiO₂Sol, due to TiO₂Since the isoelectric point is pH 6.5 and is approximately neutral, it is easily applied uniformly to the substrate by using an aqueous solution dispersed in an acid or a base. When the substrate is a metal, it is preferred to use an alkali dispersion from the viewpoint of corrosion resistance. The acid may be sulfuric acid, hydrochloric acid, acetic acid, phosphoric acid, organic acid or the like. Alkali may be ammonia, alkali metal hydroxide, but ammonia is preferred from the viewpoint of not forming metal contaminants after heat treatment. Further, an organic acid, a phosphate dispersant, a surface treatment agent, and a surfactant may be further added to the dispersion. Moreover, when the particle diameter is small, initial sintering can be formed at a low temperature, and a photocatalyst film excellent in peeling degree can be obtained at a low temperature, so TiO₂The average particle diameter of the sol is preferably 0.05 μm or less, more preferably 0.01 μm or less.

The coating method for the substrate is preferably carried out by spraying, dip coating, roll coating, spin coating, CVD, electron beam evaporation, sputtering or the like of the above-mentioned raw materials, and a coating film is inexpensively obtained.

The heat treatment can be carried out by using a heat treatment in an atmosphere such as an electric furnace or a gas kiln or using a hot press or the like.

On the other hand, prepare at least one solution of copper, silver, iron, cobalt, platinum, nickel, palladium, cuprous oxide (solution containing metal ions), coated on rutile TiO₂On the film. When the aqueous metal salt solution is applied, it is preferred to use a method in which the aqueous metal salt solution does not permeate to the back surface of the substrate. The solution in the metal salt solution may utilize water, ethanol or the like. It is also effective to use an alcohol when using water, and an unsaturated hydrocarbon or the like as a gasification oxidant. Further, when it is used as an ethanol solution, diethyl ether, acetone, and methanol are not suitable for rusting of a metal substrate as compared with other solvents, and the drying speed is fast and harmless, so that it is most suitable.

Then, in order to increase the carrying efficiency of the aqueous solution of the metal salt, it is dried at room temperature to about 100 ° C, and irradiated with a light having a wavelength of 390 nm or less to a metal salt to reduce the metal ion in the rutile TiO.₂The film precipitates the metal to cure. Here, the lamp used for irradiation is an ultraviolet lamp, a BLB (Black Light Blu) lamp, a xenon lamp, a mercury lamp, a fluorescent lamp, or the like. At this time, in order to improve the irradiation efficiency, it is preferable to irradiate the light to the surface vertically.

Specific embodiments are given below.

Example 45

Coating an average particle size of 0.01 μm TiO by spraying₂The ammonia dispersion of sol is formed on a 10 cm square alumina substrate and fired at 900 ° C to form rutile TiO.₂film. Next, the rutile TiO is sprayed₂An aqueous solution of copper acetate was applied to the film, followed by photoreduction (light source 20 W BLB lamp, sample at a distance of 10 cm from the light source, and irradiation for 10 seconds) to obtain a sample. The photoactivity A (L) of the obtained sample was evaluated.

The photoactive A (L) is an absolute value of the inclination when the reaction curve is approximately a straight line when the gas concentration is the Y coordinate and the reaction time is the X coordinate. That is, when Xt is the concentration of t hours, Xt=X₀‧10^-A(L)t(1) Therefore, a certain decomposition gas is passed through a thin layer of photocatalyst irradiated with ultraviolet light, and the concentration of the decomposition gas which is reduced by t hours is observed. In this experiment, the decomposition gas system used methyl sulphuric acid with a malodorous component, and the sample was placed in a cylindrical container with a diameter of 26 cm and a height of 21 cm adjusted to an initial concentration of methyl mercaptan, and a 4W BLB fluorescent lamp was irradiated from a light source of 8 cm. The change in methyl mercaptan concentration from time is obtained.

The results obtained are shown in Figures 52 and 53. Figure 52 and Figure 53 show the correlation between copper concentration and photoactivity A (L). Figure 52 shows the photo-reduction of the sprayed copper acetate aqueous solution after drying and the photoreduction without drying. The result of the aqueous solution of copper acetate in the state.

After the spraying of Fig. 53, when photo-reduction of copper acetate in a state without drying, even if the copper concentration in the solution of 0.001% by weight is increased to 0.1% by weight, A(L) is still 3 × 10^-5Left and right, can't change, has become saturated.

In contrast, the sprayed copper acetate aqueous solution in FIG. 52 is dried and then photoreduced, and 0.001% by weight is 2×10.^-5Left and right, about the same degree as non-drying, but can be significantly increased to 1 × 10 when increased to 0.1% by weight^-2A (L) value of left and right.

Example 46

Rutile TiO was formed on floor tiles and wall tiles as in Example 45.₂Film, photoreduction of copper to rutile TiO₂Investigation of metal component concentration and malodor removal rate R in a film (coated with an aqueous solution of copper acetate after drying)₃₀The relationship is as shown in Fig. 54 and Fig. 55.

The figure shows that the photoreduction treatment after drying, if the concentration of the metal component in the solution can reach a certain level, the substrate is a tile and the malodorous component can also be removed.

Example 47

Coating an average particle size of 0.01 μm TiO by spraying₂The sol ammonia dispersion is formed on a 15cm square tile substrate and fired at various temperatures to form rutile TiO.₂film. Next, the rutile TiO is sprayed₂An aqueous solution of copper acetate was applied to the film, followed by photoreduction (light source 20 W BLB lamp, sample at a distance of 10 cm from the light source, and irradiation for 10 seconds) to obtain a sample. Evaluating the odor resistance characteristics of the obtained sample R₃₀。

The results obtained are shown in Fig. 56. R at 900 ° C (porosity 10%)₃₀The value is better than the rutile type that does not carry metal. Further, when the temperature is increased to 1000 ° C (porosity 3%), the sample system in which the metal is not carried is R.₃₀The value was drastically reduced, and a slight decrease was observed in the sample to which copper was added. As described above, there are two reasons why the deodorant property at 1000 ° C is lowered as compared with 900 ° C. The first is photocatalyst rutile TiO which can be in contact with the decomposition gas when the porosity is reduced.₂The area of the film is reduced, and the sample that does not carry the metal reduces the deodorizing property for this reason. Another reason is that as the porosity decreases, the area in which the metal particles can be reduced by photoreduction is also reduced. The average free path in the electronic movement is increased.

Further, Fig. 57 shows the relationship between silver concentration, copper concentration and chromatic aberration in the solution at the time of coating. As can be seen from the graph, the difference in color and brightness of copper is small compared to silver, and coloring is not remarkable. In addition, when the copper color is analyzed by ESCA (electron ray spectrometry for chemical analysis) or the like, the zero valence and the valence of copper can be checked, and it is understood that the monovalent component which is not easily colored affects Coloring.

Example 48

Coating an average particle size of 0.01 μm TiO by spraying₂The sol ammonia dispersion is formed on a 15cm square tile substrate and fired into rutile TiO at various temperatures.₂film. Next, the rutile TiO is sprayed₂A silver nitrate aqueous solution was applied to the film, and then subjected to photoreduction (light source was a 20 W BLB lamp, and the sample was irradiated for 10 seconds from the light source for 10 seconds) to obtain a sample. Evaluation of the rutile TiO of the obtained sample₂Film porosity and deodorization characteristics R₃₀And abrasion resistance, the results are shown in Figure 58.

When the porosity is 10% or more, the deodorizing property is good, and when it is 40% or less, the abrasion resistance is or more.

The abrasion resistance is measured by sliding friction using a plastic eraser, and the change in appearance is evaluated. The evaluation indexes are as follows.

: There was no change in the 40-sliding back and forth.

: There were scratches after sliding 10 times or more and 40 times or less, and the titanium oxide film was peeled off.

: There was a scratch after sliding 5 times to 10 times, and the titanium oxide film was peeled off.

X: There was a scratch after sliding 5 times or less, and the titanium oxide film was peeled off.

Example 49

Coating an average particle size of 0.01 μm TiO by spraying₂The ammonia dispersion of the sol is formed on a 10 cm square alumina substrate which is previously formed into a glaze layer, and is formed into a rutile TiO at a temperature of 850 ° C to 1000 ° C.₂film. Next, the rutile TiO is sprayed₂A silver nitrate aqueous solution was applied to the film, and then subjected to photoreduction (light source was a 20 W BLB lamp, and the sample was irradiated for 10 seconds from the light source for 10 seconds) to obtain a sample.

The obtained samples were evaluated for antibacterial properties, abrasion resistance, peeling resistance, stain resistance, acid resistance, alkali resistance, and silver colorability.

The antibacterial properties were tested using Escherichia coli W3110 strain. 0.15m of the top surface of the multifunctional material sterilized with 70% ethanol in advance<img file="TW406031B_D0085.tif" />The bacterial solution (1~50000 CFU) was placed on a glass plate (100×100) and adhered to the uppermost surface of the substrate as a sample. After illuminating the white lamp (5,200 candelas) for 30 minutes, the irradiated sample was wiped with the sterilized gauze and the sample liquid kept under the light-shielding condition was collected and collected in 10 m.<img file="TW406031B_D0086.tif" />Physiological saline, to obtain the survival rate of bacteria, as an evaluation index, +++, ++, +, - is the same as above.

The peeling resistance test is a test in which the conditions of the abrasion resistance test are more severe, and a mixed yarn eraser (LION TYPE WRITER ERASER 502) which can apply a large shear force is used instead of the plastic eraser. Specifically, the surface of the sample was rubbed with a sandpaper eraser 20 times with equal force, and the state of the flaw was visually compared with the standard sample. The evaluation criteria were as follows.

: No change at all

: A slight change can be seen under different light conditions.

: Change slightly

×: Change at a glance.

The stain resistance test is a test for stains that are not easily stained. Specifically, the evaluation method is to make a stain on the surface of the sample with a 0.5% methylene blue aqueous solution, and then washed with water to visually observe the presence or absence of stains. The evaluation criteria are as follows: : the stain can be completely removed.

: Although no stains are visible, there are still traces left.

: leave a light stain

×: The stain is clearly left behind.

Acid resistance is immersed in 10% HC<img file="TW406031B_D0087.tif" />After 120 hours of aqueous solution, the rutile TiO supported on the surface of the substrate was visually observed.₂Whether the film layer changes or not, the evaluation criteria are as follows.

: No change at all

: slight discoloration

: slightly discolored

×: Significantly discolored. The alkali-resistant system was immersed in a 5% aqueous NaOH solution for 120 hours, and the rutile-type TiO on the surface of the substrate was observed by visual observation.₂Whether the film layer changes or not, the evaluation criteria are as follows.

: No change at all

: slight discoloration

: slightly discolored

×: Significantly changed.

The silver coloring property was evaluated by visual comparison with the sample without adding silver. The evaluation criteria are as follows.

: not colored

: some micro coloring

: slightly colored

×: There is a part colored in brown

The seven items of the above evaluation are shown in Table 24. Further, Table 25 shows the film thickness and the influence of the firing temperature on the antibacterial property.

<tables><img file="TW406031B_D0088.tif" /></tables>

<tables><img file="TW406031B_D0089.tif" /></tables>

In terms of antibacterial property, when the film thickness of the photocatalyst film produced in this example is in the range of 0.1 μm or more and 1 μm or less, a good result of +++ can be obtained as long as an appropriate firing temperature is obtained. However, as shown in Table 24, when the film thickness was reduced to 0.2 μm or less, the sample fired at a high temperature of 980 ° C was a tendency of a slight decrease in the antibacterial property of ++. This may be due to the softening of the glaze layer and the local photocatalyst film buried in the glaze layer. Moreover, silver itself has antibacterial power, but the dependence of the antibacterial property on the firing temperature indicates the rutile TiO other than the antibacterial force of the composite material produced by the method of the present invention and the antibacterial action of silver.₂The result of the film properties (such as the silver system described above after the firing).

Moreover, almost all of the samples in which the photocatalyst film is sunk into the glaze layer due to softening of the glaze layer occur more or less. However, in such an embodiment, the firing temperature is at an appropriate temperature, and at least 0.1 μm or more can confirm the photocatalyst. The film is held on the uppermost layer of the glaze layer.

In terms of abrasion resistance, the film thickness of the photocatalyst film produced in this example was in the range of 0.1 μm to 1 μm. In comparison with the same manufacturing method for the sake of comparison, the sample which does not contain the glaze is Δ, and the result is excellent. This is because the glaze layer is deposited, so that the glaze is softened and the lower layer of the photocatalyst film is buried in the glaze layer during firing.

In contrast, in the peeling resistance test, when it is 0.1 μm to 0.4 μm, it is , when it is 0.4 μm or more and 0.9 μm or less, it is , and when it is 1 μm, it is ×, and it is seen that the film thickness of the photocatalyst film tends to deteriorate. . This is because the ratio of the thickness of the glaze layer buried in the film thickness is increased, so that it is easily peeled off. In the abrasion resistance test, it is said that the normal one is deteriorated in the peeling resistance test, which is caused by the difference in the shear force.

In terms of stain resistance, when the thickness of the photocatalyst film is 0.1 μm to 0.4 μm, it is , 0.4 μm to 0.9 μm is , and 1 μm is ×, and the thicker the visible light sensor film, the worse the stain resistance is.

In terms of acid resistance, the photocatalyst film of 0.1 μm to 1 μm film thickness produced in this example showed excellent effects. When it is 0.4 μm to 1 μm, it is , and when it is 0.1 μm to 0.4 μm or less, it is , and a thin film is found to have a preferable result.

In terms of alkali resistance, the photocatalyst film of 0.1 μm to 1 μm film thickness produced in this example showed excellent effects. When it is 0.4 μm to 1 μm, it is , and when it is 0.1 μm to 0.4 μm or less, it is , and a thin film is found to have a preferable result. When the photochromic property of silver is 0.1 μm to 0.4 μm, the photocatalyst film is , is 0.4 μm to 0.9 μm, and × is 1 μm, and the thickness of the visible light catalyst film is increased, which tends to be worse. This tendency is consistent with pollution resistance.

From the above seven tests, the thickness of the photocatalyst film is preferably from 0.1 μm to 0.9 μm, preferably from 0.1 μm to 0.4 μm. Moreover, when the glaze layer is fixed to the substrate via the photocatalyst film, the abrasion resistance can be improved.

Moreover, the decorative appearance is also affected by the film thickness, that is, 0.2 μm to 0.4 μm, by the interference of the visible light and the photocatalyst film, a rainbow-colored strip pattern is formed, giving a unique appearance impression. On the other hand, when the thickness is 0.2 μm or less or 0.4 μm or more and 0.9 μm or less, the above-described rainbow-colored stripe pattern is not generated, and the color of the substrate or the color of the glaze, the pattern, or the combination thereof can be directly applied.

Example 50

Coating an average particle size of 0.01 μm TiO by spraying₂The sol ammonia dispersion is formed on a 15cm square tile substrate and fired at 900 ° C to form a 0.8 μm thick rutile TiO.₂film. Then, a coating amount of copper acetate aqueous solution (solution concentration: 0.2% by weight, 0.5% by weight, 1% by weight) was applied to the surface of the tile by spraying, and then subjected to photoreduction (light source system 20W BLB lamp, sample distance from light source) 10 cm distance, irradiation for 30 seconds), the sample was obtained. The antibacterial property of the obtained sample was evaluated, and the copper support amount was obtained by recovering the residual aqueous solution after the irradiation, and calculating the difference between the amount of copper in the initial stage and the amount of copper recovered.

Figure 59 shows the correlation between copper loading and the survival rate of bacteria in the light (L) and dark (D). The following facts can be seen from the drawings.

First, the antibacterial property can be improved by carrying copper, and secondly, when the light irradiation (L) is dark (D), the antibacterial property can be improved with a small amount of copper supported. When the light is irradiated (L), the rutile TiO which restores photoactivity by carrying copper is recovered.₂The film acts as a photocatalyst. It can be seen from the figure that 0.12 μg/cm is added.²The above can be +++, add 0.3μg/cm²The above can be increased to +++.

It is well known that copper itself also has an antibacterial effect, so that increasing the amount of copper carried in the dark can also improve the antibacterial property. At this time, it carries 0.7 μg/cm.²Above ++, carrying 1.2μg/cm²The above can be increased to +++.

Therefore, it is 0.12μg/cm when evaluated at ++ level.²~0.7μg/cm², +++ level evaluation is 0.3μg/cm²~1.2μg/cm²Under the copper loading, the good antibacterial property of light (L) is due to the combination of copper and rutile TiO.₂The specific effect of the film, due to the rutile TiO₂The presence of a film can reduce the amount of copper carried. It is possible to reduce the amount of copper supported, especially in the environment where the composite material is used in a surrounding environment, and the use of copper in an environment where it is dissolved in water, for example, when used in a bathroom or a ceramic ceramic sphere, etc. Reduce the amount of dissolved.

Moreover, in the case of copper, the same effect can be obtained even in the form of cuprous oxide. This is a test of the price of copper by ESCA on the surface of the photoreduction, with a part of Cu²⁺Cu⁺You can also see the photo-recovery effect, you can imagine.

On the other hand, the amount of copper supported is 0.7 μg/cm.²Above, preferably 1.2 μg/cm²In the above case, good antibacterial properties can be obtained regardless of the presence or absence of irradiation light.

Further, Fig. 60 is a graph showing the relationship between the amount of copper coating and the amount of copper supported when the concentration of copper in the solution is 1% by weight, and it can be seen from the figure that simply increasing the amount of copper applied does not increase the amount of copper supported. Want to make the copper loading amount 0.7μg/cm²Above, it must be 0.2mg/cm²~2.7mg/cm²Want to become 1.2μg/cm²The above is preferably 0.3 mg/cm²~2.4mg/cm²。

Example 51

Coating an average particle size of 0.01 μm TiO by spraying₂The sol ammonia dispersion is formed on a 15cm square tile substrate and fired at 900 ° C to form a 0.8 μm thick rutile TiO.₂film. Then, a coating solution of a silver nitrate aqueous solution (solution concentration: 0.2% by weight, 0.5% by weight, 1% by weight) was applied to the surface of the tile by spraying, and then subjected to photoreduction (light source 20W BLB lamp, sample distance from the light source 10 cm) The distance was irradiated for 30 seconds) and the sample was obtained. The antibacterial property of the obtained sample was evaluated. Further, the silver loading amount was obtained by recovering the residual aqueous solution after the irradiation, and the difference between the initial amount of silver and the amount of recovered silver was calculated.

Figure 61 shows the correlation between silver loading and the survival rate of bacteria in the light (L) and dark (D). The following facts can be seen from the drawings.

First, copper is not the same as silver, and there is an overlap between the curves of the survival rate of light (L) and dark (D). This does not mean that silver and copper have different results, but only that the antibacterial power of silver is higher than that of copper, and the effect can be produced with a very small amount of load, so the required holding of light (L) and dark time (D) The difference between the quantities is included in the range of experimental error.

As can be seen from the figure, the carrying amount of silver is 0.05 μg/cm.²Above, preferably 0.1 μg/cm²In the above, excellent antibacterial properties can be obtained with or without irradiation of light.

On the other hand, Fig. 62 shows the relationship between the amount of silver carried and the color difference between samples without silver, and the silver loading is 1 μg/cm.²The above-mentioned color difference will suddenly differ to be 2 or more. It is obvious that the difference in color is usually observed when the color difference is 2 or more. When silver is attached, it will change from brown to black, and it is not suitable for appearance. Therefore, the color difference is preferably controlled below 2, for which the carrier amount of silver is 1 μg/cm.²The following is appropriate. The measurement of the color difference was measured by a spectroscopic color difference meter (manufactured by Tokyo Denshoku Co., Ltd.).

Further, in the above embodiments, silver, copper, platinum, palladium, gold, and nickel have been disclosed in order to prevent the active site of the photocatalyst from being covered by a surface treatment agent, a polymer material, or dust or the like to reduce the activity or to restore the activity. Metal particles such as iron, cobalt, and zinc cover a photoactive active particle active site, but when the metal-based non-ferrous metal is applied in a large amount, the original color adheres to the surface of the substrate, destroying the color of the substrate, the pattern, and the like. Design flaws.

For this reason, the decolorization method which maintains the high photocatalytic activity while not damaging the color of the substrate, the design of the pattern, etc., is described below.

Basically, the steps of the step of reacting the metal particles with the aqueous solution or gas to form a colorless or white salt on the surface of the metal microparticles by using the immobilized metal microparticles on the photocatalyst-active particles are carried out to form a metal-containing step. A method of catalyst for microparticles.

The order in which the above two steps are applied is optional. That is, after fixing the particles of the photocatalyst to the photocatalyst-active particles, the metal microparticles are allowed to react with the aqueous solution or the gas to form a colorless or white salt on at least the surface of the metal microparticles, or to react the colored metal microparticles with an aqueous solution or a gas, at least After forming a colorless or white salt on the surface of the metal microparticles, it is fixed to the photocatalyst-active particles.

It is also possible to mix the photocatalyst-active particles and the colored metal microparticles and then fix them on the substrate. In this case, for example, the step of mixing the photocatalyst-active particles and the non-ferrous metal particles is sequentially performed, the step of applying the mixed solution to the substrate, and the step of firing the mixture to fix the mixture to the substrate, and reacting with the gas at least in the metal microparticles. The step of forming a colorless or white salt on the surface.

Further, the step of firing simultaneously to fix the mixture to the substrate and reacting with the gas to form a colorless or white salt on at least the surface of the metal fine particles can be carried out.

Colored metal microparticles refer to silver, copper, platinum, palladium, gold, nickel, iron, cobalt, zinc, etc., which tend to be small, and are easily reductive metal particles.

When a solution of a colorless or white salt is formed by an aqueous solution, or when a catalyst containing metal fine particles is used in a liquid, it is preferred that the colorless or white salt formed is poorly soluble or insoluble.

When the catalyst containing the metal microparticles is used in the substrate, the photocatalyst-active particles may be fixed to the substrate in advance, and then the catalyst containing the metal microparticles may be prepared, or the catalyst containing the metal microparticles may be prepared and then fixed. On the substrate.

Pre-fixing the photocatalyst-active particles on the substrate, and then preparing the catalyst containing the metal microparticles, sequentially performing the step of forming a photocatalyst-active particle layer on the substrate, and fixing the colored metal microparticles thereon to form A colorless or white salt to cover the above-mentioned non-ferrous metal particles.

The step of forming a colorless or white salt to cover the ferrous metal particles may be, for example, a method of contacting the metal particles with a solution which can react with the above-mentioned non-ferrous metal particles, at least a colorless or white salt on the surface of the metal particles, or a metal particle. Contact with a reaction gas which can react with the above-mentioned non-ferrous metal fine particles to form at least a colorless or white salt on the surface of the metal fine particles.

Among the salts of the above-mentioned colored metal fine particles, those which are colorless or white are preferably poorly soluble or insoluble salts. These can easily form a salt at least on the surface of the metal fine particles under the reaction of the aqueous solution, and can be used stably in the environment of water surrounding.

The above non-ferrous metal microparticles are white or colorless, and may be, for example, silver chloride, silver bromide, silver iodide, silver oxalate, silver thiosulfate, silver cyanide, silver thiocyanate, cuprous chloride, bromination. Cuprous, cuprous cyanide, cuprous thiocyanate, cuprous oxide, zinc phosphate, zinc oxalate, zinc cyanide, palladium cyanide, zinc sulfide, zinc carbonate, ferrous carbonate, zinc oxide, etc. A solution for forming the above salt, for example, a silver chloride solution, a sodium chloride solution, an ammonium chloride solution, a ferric chloride solution, etc., and a silver iodide solution, a sodium iodide solution, and iodination when silver iodide is formed. The iron solution, hydrogen peroxide water, ozone water or the like is not limited thereto, and a soluble salt solution containing an anion of each salt can be widely used.

Further, the reaction gas which can form the above salt can be widely used as long as it is a gas containing an anion element of each salt. For example, when the above salt is an oxide such as zinc oxide or cuprous oxide, it can be heated in the atmosphere, oxygen, water vapor, or with O.₃The oxidant reacts to oxidize the surface of the metal microparticles to form an oxide layer.

Specific embodiments are given below.

Example 52

A titanium oxide sol having an average particle diameter of 0.01 μm was applied onto the surface of a 15 cm square tile substrate, and then heat-treated at 900 ° C to form a rutile-type titanium oxide film. The sample stopped at this stage was used as a comparative sample 1.

Thereafter, a silver nitrate aqueous solution was applied by a spray coating method, and the BLB lamp was irradiated for 10 minutes to fix silver on the rutile-type titanium oxide film. At this time, the carrying amount of silver is 1.2 μg/cm.²Brown. The sample up to this stage was Comparative Sample 2.

Then on the comparison sample 2, at 0.1 cc/cm²The ratio is coated with 0.1 m /<img file="TW406031B_D0090.tif" />The potassium iodide aqueous solution was allowed to react, and as a result, the surface of the sample turned yellowish white and finally turned white. This should be due to the formation of a silver iodide layer. This sample was used to carry out the sample 1.

The color difference, photoactivity, deodorant properties and antibacterial properties of these samples were evaluated.

When the color difference was measured, it was measured using a spectrophotometer (manufactured by Tokyo Denshoku Co., Ltd.). At this time, the standard sample is compared with sample 1. The results are shown in Fig. 63. As a result, the color difference of the sample 2 was 3.5, and the color difference of the sample 1 after the treatment with the potassium iodide aqueous solution was reduced to 1, and the chromaticity was reduced.

The photoactivity was evaluated by the ΔpH test. The results of photoactivity and deodorant properties are shown in Fig. 64. When comparing samples 1 and 2, the comparative sample 2 recovered photoactivity due to the carrier of silver, ΔpH, R₃₀(L) has good results. Further, when the sample 1 and the comparative sample 2 were compared, ΔpH and R were₃₀(L) is a numerical value of the same degree, and it is known that the photoactivity of the decolorized treatment does not change, and good characteristics are maintained.

Further, the antibacterial property was tested using Escherichia coli W3110 strain. 0.15m of the top surface of the multifunctional material sterilized with 70% ethanol in advance<img file="TW406031B_D0091.tif" />Bacteria (2×10)⁴CFU), placed on a glass plate (100 × 100), adhered to the uppermost surface of the substrate as a sample. After irradiating the white lamp (3,500 candelas) for 30 minutes, the irradiated sample (L) and the sample liquid (D) kept under the light-shielding condition were wiped with the sterilized gauze, and recovered in 10 m.<img file="TW406031B_D0092.tif" />Physiological saline, the number of bacteria was investigated.

The results of the antibacterial properties are shown in Fig. 65. Comparative sample 1 was not loaded with silver, so no antibacterial effect was observed in the dark (D). In contrast, the sample 1 was subjected to decolorization treatment, and the surface of the silver was changed to a compound, but the antibacterial effect was still obtained in the dark (D). In addition, when exposed to light (L), a stronger antibacterial effect can be seen, not only the antibacterial effect of silver, but also the effect of the rutile-type titanium oxide film on photocatalytic activity.

Example 53

After applying a glaze on a 15 cm square sanitary ceramic forming body, it is fired at 1100 to 1200 ° C, and an anatase titanium oxide sol having an average particle diameter of 0.01 μm is applied and fired at 900 to 1000 ° C to fix the gold. The red stone type titanium oxide film is formed on the sanitary ceramics green body substrate.

Then, an aqueous silver nitrate solution was applied thereon, and ultraviolet rays were irradiated onto the titanium oxide film to precipitate silver. Further, an aqueous solution of ferric chloride was applied thereon, and when it was irradiated with ultraviolet rays, it was decolored, and the color difference was reduced from 3 to 0.3. Further, in the case of antibacterial light irradiation, the sample was contacted for 30 minutes in the dark, and it was confirmed that only 10% or less of the original number of bacteria remained excellent.

Example 54

After applying a glaze on a 15 cm square sanitary ceramic forming body, it is fired at 1100 to 1200 ° C, and an anatase titanium oxide sol having an average particle diameter of 0.01 μm is applied and fired at 900 to 1000 ° C to fix the gold. The red stone type titanium oxide film is formed on the sanitary ceramics forming blank substrate.

Then, an aqueous silver nitrate solution was applied thereon, and ultraviolet rays were irradiated onto the titanium oxide film to precipitate silver. The sample was placed in a desiccator equipped with an ozone generator (ozone concentration: 10 ppm) for about 2 hours to decolorize the sample. It is confirmed that only 10% or less of the original bacteria counts, indicating excellent results.

Example 55

After coating the glaze on a 15 cm square sanitary ceramic forming body, firing at 1100 to 1200 ° C, coating a mixture of anatase titanium oxide sol having an average particle diameter of 0.01 μm in an aqueous solution of nitric acid and an aqueous solution of silver nitrate After the liquid is fired, the titanium oxide film is fixed on the sanitary ceramic preform body substrate. At this time, it is brown when it is baked at 700 ° C or lower, but is decolored when it is fired at 700 ° C or higher. It can be seen that the silver surface reacts with the components in the atmosphere. Further, the film was fired at 850 ° C to fix the anatase-type titanium oxide film on the sanitary ceramics green body substrate, and the antibacterial property of the obtained sample was measured. When the light was irradiated, it was exposed to the sample for 3 hours in the dark, and only the original bacteria were confirmed. Below 10% of the number, there are excellent results.

Example 56

After applying a glaze on a 15 cm square sanitary ceramic forming body, it is fired at 1100 to 1200 ° C, and an anatase titanium oxide sol having an average particle diameter of 0.01 μm is applied and fired at 900 to 1000 ° C to fix the gold. The red stone type titanium oxide film is formed on the sanitary ceramics forming blank substrate.

Then, an aqueous silver nitrate solution was applied thereon, and ultraviolet rays were irradiated onto the titanium oxide film to precipitate silver. Further, hydrogen peroxide water was applied thereon to decolorize it. Further, when the antibacterial light was irradiated, the sample was exposed to the sample for 3 hours in the dark, and it was confirmed that only 10% or less of the original number of bacteria showed an excellent effect.

Secondly, the mixed rutile TiO is described.₂The particles and cerium oxide improve the compactness and adhesion of the photocatalyst film while improving the activity.

The method of forming a photocatalyst film is either of the following two methods.

Pre-mixed TiO₂A method in which a sol and a cerium oxide sol are applied to a surface of a substrate and fired.

Mixed TiO₂The sol and the cerium oxide sol are carried out in an aqueous alkaline solution. In the electrochemical sense, it is possible to make both of them sufficiently dispersed when they are alkaline. The alkaline aqueous solution may be ammonia, a hydroxide containing an alkali metal or an alkaline earth metal, but ammonia is preferred because it does not cause metal contaminants after heat treatment. Further, an organic system, a phosphate-based dispersant, a surface treatment agent, and a surfactant may be further added to the dispersion.

The coating method may be a method of spraying, dip coating, roll coating, spin coating, CVD, electron beam evaporation, sputtering, or the like to form a coating film, any of which may be other methods. However, in which spraying, dip coating, and roll coating are not required, such as CVD, electron beam evaporation, and sputtering, special equipment is required, and it is advantageous to form a coating film at low cost.

After coating, the film may be dried before firing, and drying may be carried out at room temperature to about 100 °C.

The firing temperature is carried out under the conditions sufficient to generate rutile. This temperature is 830 ° C or more in the presence of cerium oxide under normal pressure.

No need to form TiO₂Solid solution with cerium oxide. Want to form TiO₂The solid body with yttrium oxide must be kept at a high temperature for a long time, and the production efficiency is not good.

Another method is to form rutile TiO₂After the film, a cerium oxide sol is added thereto and fired.

This method first coats the substrate with a titanium-containing starting material. The starting materials here can be used TiO₂Sol, titanium alkoxide, titanium sulfate, titanium chloride solution, and the like. Using TiO₂Sol, due to TiO₂Since the isoelectric point is pH 6.5 and is too neutral, it is easily applied uniformly to the substrate by using an aqueous solution dispersed in an acid or a base. When the substrate is a metal, it is preferred to use an alkali dispersion from the viewpoint of corrosion resistance. For ceramics, tiles, ceramics, etc., any dispersion of acid or alkali can be used. The acid may be nitric acid, hydrochloric acid, acetic acid, phosphoric acid, organic acid or the like. Alkali may be ammonia, alkali metal hydroxide, but ammonia is preferred from the viewpoint of not forming metal contaminants after heat treatment. Further, an organic acid, a phosphate dispersant, a surface treatment agent, and a surfactant may be further added to the dispersion. Also, the starting material of TiO₂The average particle diameter of the sol is preferably 0.05 μm or less, preferably 0.01 μm or less. Further, when the particle diameter is small, initial sintering can be formed at a low temperature, and a photocatalyst film having excellent peeling strength can be formed at a low temperature. The coating method for the substrate may be a method of coating, dip coating, roll coating, spin coating, CVD, electron beam evaporation, sputtering, or the like to form a coating film, any of which may be other The method, except that spraying, dip coating, and roll coating are not required to be as CVD, electron beam evaporation, sputtering requires special equipment, and it is advantageous to form a coating film at low cost. After coating, the film can be dried before firing. Drying is preferably carried out at a temperature of from room temperature to about 100 °C.

The coated composite material is then fired. The firing is carried out at a temperature at which rutile is formed, and is usually 900 ° C or more under normal pressure.

Thereafter, the cooled and solidified composite material is further coated with a starting material which can be used as a source of tin and fired. As a starting material for the tin source, there is a cerium oxide sol or the like. The cerium oxide sol is preferably an aqueous alkaline solution, and electrochemically, the cerium oxide sol is relatively stable when it is alkaline. The alkaline aqueous solution may be ammonia, a hydroxide containing an alkali metal or an alkaline earth metal, but ammonia is preferred because it does not cause metal contaminants after heat treatment. Further, an organic system, a phosphate-based dispersant, a surface treatment agent, and a surfactant may be further added to the dispersion.

The coating method for the substrate may be a method of coating, dip coating, roll coating, spin coating, CVD, electron beam evaporation, sputtering, or the like to form a coating film, any of which may be other The method, except that spraying, dip coating, and roll coating are not required to be as CVD, electron beam evaporation, sputtering requires special equipment, and it is advantageous to form a coating film at low cost. The film can be dried before being baked after coating. The drying is preferably carried out at a temperature of from room temperature to about 100 °C. The firing temperature can be a temperature at which the organic component is evaporated from the cerium oxide, and is 300 ° C or more under normal pressure. No need to form TiO₂Solid solution with cerium oxide. Want to form TiO₂The solid body with yttrium oxide must be kept at a high temperature for a long time, and the production efficiency is not good.

Also, rutile TiO can be formed on the surface of the substrate.₂Forming a film with a mixture of cerium oxide having a crystal grain size of 0.01 μm or less, and then fixing at least one of copper, silver, platinum, iron, cobalt, nickel, palladium, and copper oxide.

These metals have trapping electrons, thereby increasing rutile TiO₂Photocatalytic activity of a film formed from a mixture of cerium oxide having a crystal grain size of 0.01 μm or less.

In particular, copper and silver have antibacterial properties and can be antibacterial without being exposed to light, so that they can have a certain degree of antibacterial power even when they are not dark. The method of fixing at least one metal of copper, silver, platinum, iron, cobalt, nickel, palladium or cuprous oxide may be coating at least one metal salt aqueous solution of the metals, followed by photoreduction or heat treatment Method of immobilization.

The metal salt aqueous solution is basically as long as the metal species is dissolved as a cation. Specifically, it may be copper acetate, silver nitrate, copper carbonate, copper sulfate, cuprous chloride, copper chloride, platinum chloride acid, palladium chloride, nickel chloride, cobalt chloride, ferrous chloride, iron chloride.

The method of coating the aqueous solution of the metal salt may be a spraying method or a dip coating method, but it may be used in a small amount, uniformly coated, the coating film is easy to control, and it is preferable to apply the spraying method without wishing to adhere to the back surface. .

The photoreduction method is followed by irradiation of ultraviolet light to reduce metal ions in rutile TiO.₂A metal of at least one of copper, silver, platinum, iron, cobalt, nickel, palladium, and cuprous oxide is fixed to a film formed by a mixture of cerium oxide having a crystal grain size of 0.01 μm or less.

The light source that irradiates the ultraviolet-containing light may be any one that emits ultraviolet light, and specifically may be any of an ultraviolet lamp, a BLB lamp, a xenon lamp, a mercury lamp, a fluorescent lamp, or the like. In the method of irradiating light containing ultraviolet rays, it is preferable to arrange the sample so that the irradiated surface can receive light vertically. This gives the best illumination efficiency. The distance between the sample and the light source is preferably 1cm~30cm. When the distance is too close, the sample surface cannot be irradiated to a uniform illumination. The adhesion of the above metal species is likely to cause unevenness. When the distance is too far, the illumination of the light is inversely proportional to the square of the distance, and it is difficult to firmly adhere to the metal. .

In the heat treatment method, the heat is fixed to a temperature at which the rear metal is sufficiently fixed. The temperature is preferably 100 ° C or higher. However, the metal is oxidized at a high temperature of 800 ° C or higher, and the metal is preferably a metal which is oxidized and does not lose electron-trapping effect or which does not lose its antibacterial property. It is limited to silver, copper. Silver and copper are not burnt at high temperature and do not lose electron capture or antibacterial properties. They can also be produced according to the method shown below. Premixed TiO₂A method in which a sol and a cerium oxide sol are applied to a surface of a substrate, followed by coating a metal salt aqueous solution, followed by firing. According to this method, it can be completed by one firing process, which can improve production efficiency and reduce manufacturing cost.

The following are specific examples.

Example 57

Add 4~6 wt% crystal grain size 0.01μm TiO₂The sol was prepared as a suspension A in an aqueous ammonia solution adjusted to pH 11. In a separate container, 10% by weight of a cerium oxide sol having a crystal grain size of 0.0035 μm was added to prepare a suspension B in an aqueous ammonia solution adjusted to pH 11. The suspension A and the suspension B were mixed at a predetermined ratio, and then sprayed on the surface of a 15 cm square tile substrate, dried, and fired at 850 ° C for 2 hours to obtain a sample. TiO in the obtained sample₂The crystalline form is rutile. Determination of TiO by powder X-ray diffraction₂Lattice constant, result TiO₂There is no solid solution of cerium oxide in the crystal lattice. The photoactivity and abrasion resistance of the obtained samples were evaluated.

The photoactive system dripped the potassium iodide aqueous solution on the surface of the sample, and then irradiated the ultraviolet ray to the dropped potassium iodide aqueous solution for 30 minutes, and evaluated the difference between the pH value of the potassium iodide aqueous solution before the irradiation and the pH value of the potassium iodide aqueous solution after the irradiation. That is, according to this method, when the photoactivity of the surface of the sample is high, the oxidation-reduction reaction shown below can be sufficiently performed, so that the pH after the irradiation is higher than the pH before the irradiation.

Oxidation reaction: 2I^-+2h⁺=I²

Reduction reaction: O₂+2H₂O+4e^-=4OH^-

Moreover, the abrasion resistance causes the plastic eraser to perform sliding friction and evaluates the change in appearance. The evaluation index , , , × is as described above.

Figure 66 shows the effect of the weight ratio of yttrium oxide on the abrasion resistance in the film. The presence or absence of cerium oxide showed good abrasion resistance, and the result was or . Due to the high temperature treatment at 850 ° C, sintering occurs, and the particles in the film are firmly bonded to each other.

In particular, when the cerium oxide is 30% or more, it is . This is due to the TiO of the starting material.₂The particle size ratio between the sol (crystal grain size: 0.01 μm) and the cerium oxide sol (crystal grain size: 0.0035 μm) is 2 or more, so that the cerium oxide particles of the particles can be buried in the TiO.₂The voids of the particles increase the filling property and make the film denser.

Figure 67 is a graph showing the effect of the weight ratio of cerium oxide on the photoactivity in the film. For the sake of comparison, rutile TiO with good antibacterial and deodorant properties is shown here.₂Sample of copper in the middle (R₃₀60%) ΔpH, and anatase TiO with excellent antibacterial and deodorizing properties₂Sample (R₃₀It is a pH of 97%). Ruthenium-doped rutile TiO₂ΔpH is not as good as anatase TiO₂However, the rutile TiO is still more than 10% by weight, 80% or less, preferably 20% or more and 70% or less by weight of cerium oxide.₂The ΔpH of the sample carrying copper was larger, and it was found to have good photoactivity.

From this, it can be seen that when cerium oxide having an average particle diameter of 0.01 μm or more is added, the photocatalytic activity cannot be increased due to the pulverization of cerium oxide, and the position of the conductive tape is moved upward. The cerium oxide particles do not have a sufficient amount to generate active oxygen. Due to the spacing. Further, when 10% or more is disadvantageous, sufficient photoactivity cannot be produced because the amount of cerium oxide particles is insufficient. On the other hand, when the effect is 80% or more, the effect is lowered because the cerium oxide is likely to be adjacent to each other in the photocatalyst layer, and the grain grows to a high frequency of 0.01 μm or more in the heat treatment.

Comparative Example 58

Add 4~6 wt% crystal grain size 0.01μm TiO₂The sol was prepared as a suspension A in an aqueous ammonia solution adjusted to pH 11. In a separate container, 10% by weight of a cerium oxide sol having a crystal grain size of 0.01 μm was added to prepare a suspension B in an aqueous ammonia solution adjusted to pH 11. The suspension A and the suspension B were mixed at a predetermined ratio, and then sprayed on the surface of a 15 cm square tile substrate, dried, and fired at 850 ° C for 2 hours to obtain a sample. TiO in the obtained sample₂The crystalline form is rutile. Determination of TiO by powder X-ray diffraction₂Lattice constant, result TiO₂There is no solid solution of cerium oxide in the crystal lattice. The photoactivity and abrasion resistance of this sample were evaluated.

Figure 68 shows the effect of the weight ratio of yttrium oxide on the abrasion resistance in the film. The presence or absence of cerium oxide showed good abrasion resistance, and the result was . Due to the high temperature treatment at 850 ° C, sintering occurs, and the particles in the film are firmly bonded to each other. However, even if the amount of cerium oxide added is increased, the wear resistance can no longer be improved. This is due to the TiO of the starting material.₂The particle size ratio between the sol (crystal grain size: 0.01 μm) and the cerium oxide sol (crystal grain size: 0.01 μm) was approximately equal.

Figure 69 is a graph showing the effect of the weight ratio of cerium oxide on the photoactivity in the film. For the sake of comparison, rutile TiO with good antibacterial and deodorant properties is shown here.₂ΔpH of the sample carrying copper, and anatase TiO with excellent antibacterial and deodorant properties₂The ΔpH of the sample. Ruthenium-doped rutile TiO₂pH system is far less than anatase TiO₂The pH of the sample is far less than the rutile TiO₂The copper sample ΔpH was loaded.

Example 59

Add 4~6 wt% crystal grain size 0.01μm TiO₂The sol was prepared as a suspension A in an aqueous ammonia solution adjusted to pH 11. In another container, 10% by weight of a cerium oxide sol having a crystal grain size of 0.0035 μm was added to prepare a suspension B in an aqueous ammonia solution adjusted to pH 11. Suspension A and suspension B were mixed at a predetermined ratio, and then sprayed on the surface of a 15 cm square tile substrate, dried, and fired at 850 ° C for 2 hours to obtain a composite material. TiO in the obtained composite₂The crystalline form is rutile. Further, the weight ratio of cerium oxide in the film was 60%. Determination of TiO by powder X-ray diffraction₂Lattice constant, result TiO₂There is no solid solution of cerium oxide in the crystal lattice. A 5% by weight aqueous solution of copper acetate was applied to the composite by spray coating, and then dried, and photoreduced (light source: 20 W BLB lamp, light source to sample distance of 10 cm, irradiation for 1 minute) to obtain a sample. The odor resistance characteristics of the obtained samples were evaluated.

Here R₃₀It is obtained according to the following test. The decomposition gas system was treated with methyl sulphuric acid, and the sample was placed in a cylindrical container having a diameter of 26 cm and a height of 21 cm adjusted to an initial concentration of methyl mercaptan, and a 4W BLB fluorescent lamp was irradiated from a light source of 8 cm, and the irradiation was measured for 30 minutes. Calculate the methyl mercaptan concentration reduction rate as the deodorizing property of light irradiation₃₀(L). Also, the odor-reducing property R in the dark₃₀(D) was calculated by calculating the concentration reduction rate of methyl mercaptan at 30 minutes after the irradiation. The results are shown in Table 26. Further, for the sake of comparison, the samples prepared in Example 57 and Comparative Example 58 (weight ratio of cerium oxide 60%) were also tested. As is clear from Table 26, the effect shown below was obtained by adding copper.

<tables><img file="TW406031B_D0093.tif" /></tables>(SnO₂The weight ratio is 60%)

As can be seen from Table 26, compared with the sample of Example 57, R₃₀(L) is slightly increased, which may be due to the electron capture effect of copper. Further, compared with the samples of Example 57 and Comparative Example 58, R₃₀(L) can be significantly improved. This increase in dark activity should be due to the catalytic effect of copper.

It can be seen from the above description that the material of the photocatalyst film is formed on the surface of the substrate by using the TiO of the photocatalyst film.₂When the composition is turned into a rutile type, the sealing temperature can be made to have sufficient density and TiO₂Film strength. At this time, in addition to rutile TiO₂In addition, when cerium oxide having a crystal grain diameter of 0.01 μm or less is used, the photocatalytic activity of the photocatalyst film can be further enhanced.

In addition, when at least one of copper, silver, platinum, iron, cobalt, nickel, and palladium is immobilized on the photocatalyst film, the photocatalytic activity can be further enhanced by electron trapping.

As described above, the present invention relates to antibacterial, antifouling, deodorizing or decomposable NO_XThe multifunctional material of the photocatalytic function of harmful substances is very suitable for wall materials, tiles, glass, mirrors, circulation filtering devices, such as artificial waterfalls for water circulation or stone used for fountains, or toilets, washstands, etc. Sanitary ceramics. Hospital equipment such as MRSA and other hospitals for the prevention of infection, residential equipment, anti-materials, anti-virus equipment, etc.