Photocatalyst, photocatalyst device and housing apparatus

Description: TECHNICAL FIELD [Detailed description of the invention]

【0001】

[Technical field to which the invention belongs]

The present invention relates to a photocatalyst that uses a photocatalyst semiconductor to remove an organic compound or an inorganic compound suspended in a gas or liquid (called a fluid), and a device using the photocatalyst.

【0002】

[Conventional technology]

The number of petrochemical products is increasing, and complex contamination of harmful organic compounds is becoming a problem both inside and outside the living environment. As a means for solving this, there is a purification method using oxidative decomposition by a photocatalytic semiconductor.

【0003】

For example, there is a method in which a photocatalytic semiconductor is supported on the surface of a substrate constituting a device or an instrument, and the device or the instrument is placed in a fluid in which a harmful organic substance is suspended so that the harmful organic substance is brought into contact with the photocatalytic semiconductor. In this case, in order to exert the photocatalytic function at a high level, it is necessary that the area of the photocatalytic functional layer is large and that the photocatalytic semiconductor is sufficiently activated by electromagnetic waves having an excitation wavelength.

【0004】

Therefore, various proposals have been made conventionally regarding a technique for increasing the surface area of a substrate and a film forming technique for forming a photocatalytic functional layer (Japanese Patent Laid-Open Nos. 5-309267 and 8-196903).

【0005】

However, these have drawbacks such as a low rate of activation by electromagnetic waves of excitation wavelength even if the area of the photocatalyst functional layer is increased by simply increasing the surface area, or poor contact efficiency between the fluid and the photocatalyst semiconductor. ..

【0006】

Further, in order to form an apparatus or an instrument, it is preferable that the substrate supporting the photocatalytic semiconductor has a flexibility that allows molding such as press working, and that can be rolled or bent. However, in particular, a substrate whose material is an inorganic material does not have such a condition, and the range in which a photocatalyst can be used is narrow. Japanese Patent Application Laid-Open No. 8-215577 uses a photocatalyst having a deformability by using a mesh-like structure (SUS304, wire mesh with a mesh size of 0.273 mm and a wire diameter of 0.15 mm # 60) having a mesh size of 0.5 mm or less. Although proposed, this does not disclose a structure in which particles are laminated on the surface of the substrate to increase the surface area. Further, Japanese Patent Application Laid-Open No. 9-262481 discloses the use of a photocatalyst and titanium peroxide sol, but does not disclose a structure in which particles for increasing surface area are laminated on the surface of a substrate.

【0007】

[Problems to be Solved by the Invention]

INDUSTRIAL APPLICABILITY According to the present invention, a photocatalyst body capable of expanding the surface area of a substrate, activating the photocatalytic functional layer formed on the surface thereof almost uniformly, and increasing the contact efficiency between the fluid and the photocatalyst semiconductor, and a photocatalyst using the same. The subject is the provision of equipment.

【0008】

[Means for solving problems]

The basic structure is that particles for increasing the surface area are laminated and fixed on the surface of the substrate, and a photocatalytic functional layer is formed on the surface of the particles to form a photocatalyst. Coarsely laminated as the distance from the substrate increases. The photocatalytic semiconductor may be attached to the surface of the substrate in addition to the surface of the particles.

【0009】

When the photocatalyst is used for separation treatment of sewage, factory wastewater, etc., or for separation or concentration treatment of solutions in the chemical industry, the particles for increasing the surface area are coarse on the substrate side and are densely laminated as the distance from the substrate increases. It is preferable to do so.

【0010】

The substrate is made of ceramic, metal, organic polymer (for example, synthetic resin), wood, paper, etc., and is in the form of a plate, a solid (cube, rectangular parallelepiped, sphere, and a combination thereof), and is dense and non-breathable. In addition to the structure, a porous structure, a honeycomb structure, and a structure having irregularities on the surface can be taken.

【0011】

The particles for increasing the surface area are made of ceramic, metal, or synthetic resin, and are often spherical or amorphous, but may also be scaly or flaky. When a melting means such as baking is used for fixing to the substrate, it is preferable that the material is the same as that of the substrate because of its good compatibility. However, even if the materials are different, it can be fixed without any problem by using an appropriate amount of an appropriate binder.

【0012】

If the substrate and the particles for increasing the surface area are made of different materials, it is necessary to match the coefficient of linear expansion or to maintain the elasticity commensurate with the linear expansion of either material. Is. Binders include inorganic glass, frit (glaze), metal powder, and ordinary thermoplastic resin.

【0013】

In order to stack particles for increasing the surface area, there are means such as repeating transfer (printing) using a screen in addition to repeating spraying and dipping several times. Then, in order to laminate the particles coarsely as the substrate side is densely separated from the substrate during lamination, the degree of dispersion (density) of the particles in the spray liquid or dipping liquid is adjusted, or the coarseness of the screen used for printing is adjusted. select. It is also possible to select the particle size of the particles to be laminated.

【0014】

Further, it is also possible to select the laminated structure in the cross section. That is, several screens that can be accurately positioned are used, and the structure is such that the substrate side is the base side and the apex is provided at a position away from the substrate in the cross-sectional form of the stack. Even with this structure, the particles for increasing the surface area are as a result of being coarsely laminated as the substrate side is densely separated from the substrate.

【0015】

In the photocatalytic functional layer, a sol solution containing a photocatalytic semiconductor such as TiO2 is adhered to the surface of a substrate on which particles for increasing the surface are fixed by spraying or dipping, dried, and then 50 ° C to 500 ° C. Formed by baking at a temperature below ° C. The fixed temperature is important for maintaining the performance of the substrate. When the substrate and particles for increasing the surface area are resistant to heat such as inorganic substances, the temperature is high, and when synthetic resin or paper is used, the temperature is low. In the case of organic polymers such as synthetic resins and paper, adhesives may be used.

【0016】

If amorphous titanium peroxide or titanium oxide is mixed in the sol in a titanium weight ratio (dry amount) in the range of 1: 1 or 1: 5, the photocatalytic semiconductor can be mixed at a relatively low temperature. The particles can be firmly supported.

【0017】

Furthermore, in order to improve the decomposition performance by oxidation-reduction by mixing a small amount of Pt, Ag, Rh, RuO2, Nb, Cu, Sn, NiO particles for functional complementation such as anti-mold sterilization, or by adding an adsorption function. Inorganic materials such as zeolite, silica (silicon dioxide), alumina, zinc oxide, magnesium oxide, ruthenium oxide, zirconium phosphate, or various activated carbons, porous phenol resin or melamine resin are mixed in one or more. Sometimes.

【0018】

When the particles on the surface layer of the substrate to which the photocatalytic semiconductor directly adheres are synthetic resins, the surface is protected by spraying a protective material such as an aqueous solution of titanium peroxide so that the particles themselves are not decomposed by the photocatalytic function. The photocatalyst functional layer is formed after the base treatment for forming the film is applied. In either case, if a film is formed in advance with an aqueous solution of titanium peroxide, the adhesion and ductility of the TiO2 sol solution will be improved and it will be easier to get wet, and the photocatalytic functional layer will be uniformly spread on the surface of the particles to increase the surface area. Moreover, it can be widely formed. The titanium peroxide aqueous solution has excellent malleability even when the substrate is a metal such as SUS, and is effective for widely and uniformly applying the TiO2 sol solution. The aqueous solution of titanium peroxide also functions as a binder, but it does not contain ceramics in composition and has good compatibility with metals, so even if the photocatalytic functional layer formed on the surface of the substrate bends or vibrates. There is little peeling.

【0019】

Other photocatalytic semiconductors include ZnO, SrTiO3, CdS, CdO, CaP, InP, In2 O3, CaAs, BaTiO3, K2 NbO3, Fe2 O3, Ta2 O5, WO3, SaO2, Bi2 O3, NiO, Cu2 O, SiC, SiO2, There are MoS2, MoS3, InPb, RuO2, CeO2, etc. Among them, titanium oxide TiO2 (anatase type) is inexpensive, has stable characteristics, and is harmless to the human body.

【0020】

The catalytic function of a photocatalytic semiconductor is that electron cleavage occurs in the semiconductor by irradiating it with an excitation wavelength equal to or greater than the band gap of a semiconductor such as metal oxide (in the case of electromagnetic waves TiO2 with an excitation wavelength, the ultraviolet region), and OH- It generates active radical hydroxyl groups and active oxygen of O2- and oxidizes organic compounds in contact with them, or decomposes them by reducing action. As a result, foul odors and oil stains can be cleaned. In addition, the same function can kill bacteria and viruses (sterilization).

【0021】

In this structure, since the surface area of the substrate is increased by the particles, the area of the photocatalytic functional layer is large, and the particles for increasing the surface area are coarsely laminated on the substrate side as they are densely separated from the substrate. Therefore, the electromagnetic wave of the excitation wavelength irradiated from the outside easily reaches the photocatalytic functional layer of the particles in the deep part of the laminated structure, and the photocatalytic functional layer is activated in a wide range.

【0022】

Further, since the fluid passing through such a laminated structure portion hits the wall of the laminated structure and is reflected, or enters a recess and temporarily stays there, there are many opportunities for organic substances suspended in the fluid to come into contact with the photocatalytic semiconductor. .. Therefore, the photocatalyst has high performance.

【0023】

The substrate may be a woven shape material formed by weaving or knitting a wire rod. The wire includes natural fibers, synthetic fibers, monofilaments and twisted yarns, but when the photocatalyst is formed as a component of a device or an appliance, a metal wire is preferable. Iron is economical as a metal wire, and copper has antibacterial properties in itself. Titanium and stainless steel have excellent rust prevention and durability, and aluminum alloys and zinc alloys are rustproof and lightweight at the same time.

【0024】

Tatami-woven or straw-woven thin stainless steel wires are rigid, and components of equipment and appliances can be made by stacking several sheets. In this case, if fine particles of stainless steel are used as the particles for increasing the surface area, the desired laminated structure can be easily obtained, and a flexible photocatalyst can be obtained.

【0025】

Further, such a woven shape material has fine pores (about 1 μm to 2 mm) in the texture, and a photocatalyst based on this can exhibit a function as a filter as well as a photocatalyst function.

【0026】

When the particles for increasing the surface area of the substrate are laminated and fixed to the substrate, if an appropriate binder, for example, inorganic glass, metal powder such as Sn, Cu, etc. is interposed and baked, the particles are interleaved with each other and with the substrate. A cross-linked portion is formed between the particles to strengthen the fixation of the particles, and the structure due to the cross-linking has elasticity, so that the photocatalyst as a whole exhibits some flexibility. When the particles for increasing the surface area are metal, the crosslinked portion can be formed by sintering at a high temperature in vacuum without the intervention of a binder.

【0027】

The photocatalyst body constructed as described above can be used in various forms, but it may be used by forming photocatalyst functional layers on both sides of a single flat substrate. In this case, an electromagnetic wave source of excitation wavelength is arranged along both side edges of the flat plate, one surface (front) of the flat plate is irradiated with the electromagnetic wave supply source of one excitation wavelength, and the other surface (front surface) is irradiated with the electromagnetic wave supply source of the other excitation wavelength. Be sure to irradiate the back).

【0028】

That is, the flat photocatalyst is arranged along the diagonal line of the rectangle in the region of the rectangular cross section accommodating the electromagnetic wave supply source of the excitation wavelength on both sides. With this configuration, a device including a photocatalyst and an electromagnetic wave source having an excitation wavelength can be thinly formed. Moreover, if the laminated structure of particles for increasing the surface area of the substrate is formed so that the substrate side is the base in the cross section and the apex is located at a position away from the substrate, the electromagnetic wave supply source of the excitation wavelength is on one side of the flat plate. Even if it is located, the photocatalytic functional layer is irradiated with electromagnetic waves of excitation wavelength almost evenly.

【0029】

As a result, the electromagnetic wave supply source of the excitation wavelength located in front of the photocatalyst does not hinder the movement of the fluid, and it is adopted when it is difficult to arrange the electromagnetic wave supply source of the excitation wavelength in front due to the structure. be able to.

【0030】

When the substrate has a large number of fine through holes, this photocatalyst can be used as various filters. When used not only as a filter as an element, but also as a gas filter that circulates in the refrigerator, for example, by constructing the inner wall of the refrigerator that is sealed like a refrigerator, vegetables and fruits such as ethylene gas can be used from the air inside the refrigerator. It is possible to remove harmful gas that causes waste, and also to remove unpleasant odors such as hydrogen sulfide and mercaptan.

【0031】

In this case, since the inner wall functions as a filter, the volume inside the refrigerator is not reduced and the filter does not get in the way as compared with the case where the filter is separately provided in the refrigerator.

【0032】

Further, such a photocatalyst can have a sound deadening function, a visual shielding function, or a wave eliminating function or a defoaming function when the fluid is in a liquid phase, as well as a cleaning function depending on the mode of use.

【0033】

Muffling is, for example, when a photocatalyst is used as a boundary wall plate that separates a roadway from a human road on a road. By forming a laminated structure that is coarse at a position closely separated from the substrate, sound waves are guided to the complicated internal space of the laminated structure and the propagated energy is absorbed.

【0034】

The visual shielding function is a function of blocking the passage of light, which makes it possible to use the photocatalyst as a partition or the like. In addition, wave-dissipating is similar to absorbing sound waves. The wave motion of the liquid makes the contact opportunity between the organic compound suspended in the liquid and the photocatalytic semiconductor non-uniform, but due to the above-mentioned laminated structure, the fluid temporarily stays in the internal space of the laminated structure, and the contact opportunity with the photocatalytic semiconductor is almost equal. Become uniform.

【0035】

The bubbles present in the liquid cover the surface of the photocatalyst and hinder the contact with the organic compounds in the liquid, but the bubbles colliding with the laminated structure are decomposed into small bubbles by complicated irregularities, and a wide range of photocatalysts are used. It does not cover the functional layer.

【0036】

When such a photocatalyst is used as a solid-liquid separation means (filter) for decomposing organic compounds suspended in a liquid and removing fine particles in the liquid, the arrangement of particles for increasing the surface area is arranged. Contrary to the above, the side close to the substrate may be coarsely configured and the side far from the substrate may be densely configured to facilitate backflow regeneration for recovering the clogging of the filter.

【0037】

In addition, this photocatalyst can be used for air conditioners and exhaust gas treatment equipment, filters, indoor wallboards for toilets and buildings, algae-proof ornamental water tank walls, swimming pool walls, and the like.

【0038】

BEST MODE FOR CARRYING OUT THE INVENTION

Examples of photocatalyst production [Example 1] A flat tatami woven wire mesh (# 40/200 mesh) made of austenitic stainless steel SUS316 as a wire rod is rolled at a rolling reduction of 30% to prepare a substrate having a thickness of 280 μm, and an average particle size of 10 μm is prepared on both sides thereof. SUS316L powder is applied to a thickness of 60 μm and then sintered (950 ° C × 10 hr) to form a base film. Then, SUS316L powder with an average particle size of 12 μm is applied to a thickness of 60 μm, rolled (rolling ratio 15%), and then sintered (730 ° C × 10 hr in a hydrogen atmosphere), with an average pore diameter of 3 μm and a thickness of 0.34 mm. A plate-shaped substrate was prepared. Water was used as a binder for sintering the SUS316L powder.

【0039】

Next, as a photocatalytic functional material, an amorphous titanium peroxide aqueous solution (0.84 w%): anatase type titanium oxide aqueous solution (0.84 w%): colloidal silica aqueous solution (0.84 w%) was mixed at a ratio of 3: 7: 0.1. Spray 0.1g / 25cm2 (wet state) on the surface of the substrate. Then, after drying at room temperature, it was dried by heating (300 ° C × 1 hr) to obtain a photocatalyst.

【0040】

When the cross section of the photocatalyst 1 is observed, as shown in FIG. 1 outlined, the rolled flat tatami woven wire mesh is used as the substrate 2, and the particles 3 of SUS316L having an average particle size of 12 μm are densely packed in the portions on both sides thereof close to the substrate 2. The first layer 4 is formed side by side, and the second layer 5 is formed on the outside in a form in which SUS316L particles having an average particle size of 10 μm are relatively coarse and have a lot of space.

【0041】

FIG. 3 shows a cross section of the substrate 2 magnified 800 times, and a laminated structure having many gaps due to round particles 3 can be seen on the surface of the wire mesh. In addition, FIG. 4 is a part of the cross section of the substrate 2 magnified 5000 times, and it can be seen that the stainless steel particles 3 are bonded to each other by the cross-linked portion 6 formed by melting the material of the particles. Can be done.

【0042】

Although not shown, a photocatalyst semiconductor is fixed to the surface of these stainless steel particles 3 to form a photocatalyst functional layer. The photocatalyst functional layer uses titanium oxide "TO sol" (trade name: Tanaka Transfer Co., Ltd.), is sprayed onto the surface of the substrate 2 by a spray method, dried, and sintered at approximately 200 ° C.

【0043】

[Example 2] A flat tatami woven wire mesh (# 40/200) made of SUS316 is rolled at a rolling reduction of 30% to prepare a substrate having a thickness of 280 μm, and SUS316L powder having an average particle size of 30 μm mixed with water is applied to both sides thereof. It was applied to a thickness of 100 μm and sintered in a vacuum furnace (960 ° C × 2 hr) to prepare a flat film substrate having an average pore size of 30 μm.

【0044】

After drying at room temperature, first to third mask screens having a large number of micropores on one surface were prepared, and these were used sequentially from the first mask screen, and SUS powder was mixed into the water. Prints are repeated using the sol as ink. Dry at room temperature between each print. The center positions of the holes of each mask screen were the same for all screens, and the diameters of the fine holes were smaller in order from the first screen.

【0045】

Next, as an adsorption / photocatalyst functional material, amorphous titanium peroxide aqueous solution (0.84 w%): anatase type titanium oxide aqueous solution (0.84 w%): colloidal silica aqueous solution (0.84 w%): coconut shell activated carbon (converted to weight of other aqueous solutions) Is mixed at a ratio of 3: 3: 0.1: 0.3 and sprayed 0.6 g / 25 cm2 (wet state) on the surface of the substrate. Then, the whole was heated and dried (300 ° C × 1 hr) to obtain a photocatalyst.

【0046】

When observing the cross section of this photocatalyst 1, as shown in FIG. 2, the rolled flat tatami woven wire mesh is used as the base 2, and SUS316L particles 3 having an average particle size of 30 μm are formed on both sides of the base 2 from the base. A large number of pyramidal convex portions 7 having vertices at distant positions are formed and laminated.

【0047】

It can be said that this laminated structure has a structure in which particles are dense in a portion close to the substrate 2, and the particles are gradually coarser toward the outside and have a large amount of space. Further, although not shown, a photocatalyst semiconductor or activated carbon is fixed on the surface of these stainless steel particles 3 to form a photocatalyst functional layer. Three evaluation samples (110 mm × 160 mm) were collected from the photocatalyst 1 of Example 2, each was placed in a transparent resin bag, and three types of evaluation gases were individually introduced into each bag and sealed. The evaluation gas is ammonia gas (60ppm), acetaldehyde gas (50ppm) and ethylene gas (70ppm). Then, a black light light source (FL20S / SL-B, 20W) was set at a position 150 mm away from the sample and irradiated, and the concentration of the evaluation gas with the passage of time was measured. As a result, as shown in FIGS. 9, 10 and 11, the gas concentration in the bag of ammonia gas and acetaldehyde gas became 0 ppm after 10 minutes, showing a remarkable decomposition action. As for ethylene gas, the gas concentration in the bag decreased to 10 ppm after 480 minutes, showing a considerable decomposition effect. In the figure, the film-formed product is the completed photocatalyst 1 of Example 2, and the film-formed product is the case of only the substrate 2 used in Example 2.

【0048】

FIG. 5 shows a photocatalyst device 9 in which a photocatalyst body 1 formed on a flat plate is fitted in a frame 7 and a fluorescent lamp 8 as an electromagnetic wave supply source of an excitation wavelength is integrally incorporated. The photocatalyst 1 has a pyramid-shaped convex portion shown in Example 2, and the frame 7 is made of stainless steel and is formed in a rectangular shape. The frame material constituting the vertical frames on both sides provides a space for accommodating the fluorescent lamp 8.

【0049】

Therefore, when the frame 7 is viewed from above, it becomes a long rectangle corresponding to the cross-sectional shape, and the flat plate photocatalyst 1 is arranged along the diagonal line thereof. With this structure, one surface (front side) of the photocatalyst body 1 is irradiated by one fluorescent lamp 8 and the other surface (back surface) is irradiated by the other fluorescent lamp 8, and the photocatalyst functional layer on each surface is activated. ..

【0050】

Ultraviolet rays from the fluorescent lamp 8 irradiate the surface of the photocatalyst 1 from one side, but the surface of the photocatalyst 1 is reflected by an uneven surface on which particles 3 for increasing the surface area are laminated and viewed from the fluorescent lamp side. Ultraviolet rays reach the shadowed portion, and the entire surface of the photocatalyst functional layer on the surface of the photocatalyst is almost activated, so that an efficient photocatalyst function is exhibited. Since this photocatalyst device 9 is breathable, it can be used not only as a filter but also as a partition that also serves as a room air purification device.

【0051】

FIG. 6 shows a cross section of the low temperature storage chamber 10 for storing vegetables and the like. The low temperature storage chamber 10 is sealed by a door (not shown), but the flat photocatalyst 1 shown in Example 1 is attached in the form of a lining with a gap 12 inside the box-shaped outer wall 11. ing. In the gap 12 of the ceiling portion, a flat plate type reflector 13 and fluorescent lamps 8 as an ultraviolet ray supply source are arranged diagonally on both sides thereof.

【0052】

As shown in FIG. 7A, the flat plate type reflector 13 has reflection pieces 14 formed on both sides and reflects ultraviolet rays from the fluorescent lamps 8 on both sides in the same direction, that is, in the direction of the photocatalyst 1 on the ceiling. When the light catalyst functional layer is present on both sides of the panel like the central partition wall, the reflector 13 having the reflective layers 18 on both sides is used as shown in FIG. 7 (b).

【0053】

In this embodiment, the reflective layer 18 is formed by laminating SUS particles baked on both sides of the stainless steel plate 19. The particles are densely arranged with a small diameter on the 19th side of the steel sheet and coarsely arranged with a large diameter on the side away from the substrate.

【0054】

In the gap 15 of the wall portion, an elliptical curved reflector 16 having a mirror surface inside and a fluorescent lamp 8 as an ultraviolet source are arranged inside the central portion thereof. The spaces 13 and 15 are connected to ducts 17 on both sides of the ceiling, and the internal air of the storage chamber 10 is circulated through the photocatalyst 1 which is an inner wall by a circulation pump. Then, organic compounds that are inconvenient for storing vegetables such as ether and odor floating in the air when passing through the photocatalyst 1 are decomposed by oxidation / reduction action.

【0055】

When the substrate 2 has moldability as in the embodiment, the photocatalyst 1 as the inner wall is not formed by combining flat plates, but can be formed into a container shape at once by press working. If peeling of the photocatalyst functional layer becomes a problem, the photocatalyst functional layer may be formed after the substrate 2 is pressed.

【0056】

FIG. 8 shows an example in which the photocatalyst 1 is used as a measure against deodorization of the toilet, and the photocatalyst 1 is attached to the ceiling as a flat plate with a gap. Reference numeral 8 is a fluorescent lamp, which is a source of ultraviolet rays. In the indoor space of a toilet, indoor air is normally flowing by a ventilation device at all times, and the suspended organic compound, which is the source of odor, collides with the photocatalyst 1 on the air flow and is decomposed by the photocatalyst functional layer. Since the surface of the photocatalyst 1 has an uneven laminated structure with voids, it is easily divided during contact with suspended organic compounds and passage through pores to easily receive a photocatalytic function, and the deodorizing effect is improved.

【0057】

[Effect of the invention]

According to the configuration according to claims 1 and 2, the photocatalyst body has many voids and irregularities on the surface layer portion, the area of the photocatalyst functional layer is large, the oxidizing / reducing power is large, and the organic compound floats in the fluid. There are many opportunities for contact with the photocatalyst functional layer, and a photocatalyst with high performance can be obtained.

【0058】

According to the configuration according to claim 3, in addition to the action and effect exhibited by the configurations of claims 1 and 2, the uneven structure of the surface regularly reflects ultraviolet rays emitted from one direction to substantially the photocatalytic functional layer. The entire surface can be activated, and a high-performance photocatalyst can be obtained. According to the configuration according to claim 4, it is possible to obtain a photocatalyst as a filter excellent in solid-liquid separation as well as decomposition of an organic compound suspended in a liquid.

【0059】

According to the configuration according to claim 5, since the photocatalyst whose substrate is a woven shape material has flexibility, the photocatalyst can be mounted even in a place where the shape is complicated or the shape changes. Further, the photocatalyst whose substrate is a woven shape material has a filter function such as air permeability.

【0060】

According to the configurations of claims 6 and 7, the photocatalyst having the substrate on which the woven shape material is laminated functions as a dense filter in which fine pores are overlapped. In addition, since it exhibits rigidity, it can be used as a component of a panel or a device by itself. On the other hand, since it can be bent, it can be press-molded, and various three-dimensional constituent members having a photocatalytic function can be produced.

【0061】

According to the configuration according to claim 8, by using stainless steel as the material of the substrate, a photocatalyst having high durability and capable of press working can be obtained. According to the configuration according to claim 9, the structure of tatami weave or straw mat weave imparts filter performance such as flexibility and ventilation to the substrate, and a photocatalyst suitable for a space having a complicated shape can be obtained.

【0062】

According to the configuration according to claim 10, since the laminated structure of particles bonded to each other by the molten portion of stainless steel exhibits a certain degree of elasticity, a photocatalyst having excellent flexibility can be obtained. According to the configuration according to claim 11, even if the electromagnetic wave supply source of the excitation wavelength is arranged on both sides of the photocatalyst formed on the flat plate, the photocatalyst functional layer can be efficiently activated, and the photocatalyst function can be efficiently performed. It can be demonstrated.

【0063】

According to the configuration according to claim 12, it is possible to obtain a high-performance filter capable of simultaneously purifying by supplementing a solid substance suspended in a fluid and decomposing an organic compound that cannot be removed by a filter. According to the configuration according to claim 13, organic compounds harmful to storage such as vegetables and organic compounds which are the basis of odor can be removed from the inside of the refrigerator to enable long-term storage and storage.

[Simple explanation of drawings]

[Figure 1]

Schematic cross-sectional view of the substrate (first example) [Figure 2]

Schematic cross-sectional view of the substrate (second example) [Fig. 3]

Photograph (partial cross section) showing the bonding between particles and between particles and a substrate [Fig. 4]

Photograph showing the cross-linking between particles [Fig. 5]

Perspective view showing a flat photocatalytic device [Fig. 6]

Front view showing the low temperature storage cut [Fig. 7]

Both (a) and (b) are plan views showing examples of reflectors. [Fig. 8]

Front view schematically showing the form of use in the toilet [Fig. 9]

Measurement results for evaluation gas / ammonia [Fig. 10]

Measurement results for evaluation gas and acetaldehyde [Fig. 11]

Measurement results for evaluation gas / ethylene [Explanation of symbols]

1 Photocatalyst 2 Hypokeimenon 3 Stainless steel particles 4 1st layer 5 2nd layer 6 Convex part 7 frames 8 Fluorescent lamp 9 Photocatalytic device 10 low temperature storage room 11 outer wall 12 Ceiling gap 13 reflector 14 Reflective piece 15 gap (wall) 16 Curved reflector 17 Duct 18 Reflective layer 19 Stainless steel plate