Ceramics having bacteriocidal action

Description: TECHNICAL FIELD [Detailed description of the invention]

【0001】

[Technical field to which the invention belongs]

The present invention relates to ceramics having a particularly bactericidal action.

【0002】

[Conventional technology]

Anatase-type TiO2 is known as a photocatalyst that promotes a deodorizing reaction by being irradiated with ultraviolet rays. Then, the applicant has previously proposed a proposal that the wall surface of the living space has a deodorizing wall function by applying a raw material obtained by kneading the photocatalytic particles into a binder to the surface of a member constituting the wall surface of the living space and then firing the material. I am doing it. As shown in FIG. 10, the structure forms a binder layer 101 on the surface of the wall material 100, and the photocatalyst particles 102 are held in the binder layer 101.

【0003】

[Problems to be Solved by the Invention]

On the above-mentioned wall surface, the photocatalytic action of irradiation with ultraviolet rays exerts a function of decomposing organic substances (removing dirt) and deodorizing. However, since the photocatalyst itself does not exert an active antibacterial effect, it cannot be said that it is sufficient when applied to sanitary ware and the like.

【0004】

[Means for solving problems]

In order to solve the above problems, in the present invention, in a ceramic having a glaze layer formed on the surface of the base material, copper or silver is contained in the glaze layer as a metal having a bactericidal action in addition to titanium oxide. With such a configuration, an antibacterial effect is exhibited in addition to the deodorizing effect due to the photocatalytic action.

【0005】

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. Here, FIG. 1 is a view showing the photocatalytic function according to the present invention in the order of steps for manufacturing a pottery, and FIG. 2 is an enlarged cross-sectional view of the pottery (tile) obtained by the same method.

【0006】

In the method of the present invention, as shown in FIG. 1 (a), the glaze layer 2, which is a material that is not easily decomposed by the photocatalytic function of the photocatalytic particles, is first applied to the surface of the base material of the ceramic 1, and then in FIG. As shown, anatase-type TiO as a photocatalytic particle using a spray or the like on the surface of the glaze layer 2.₂The particles 3 and Cu, Ag, etc. as antibacterial agents are sprayed in a sol form, and then the glaze layer 2 is heated and melted as shown in FIG. 1 (c), and then cooled and solidified.

【0007】

As a method of adding Cu, Ag, etc., NH₃TiO adjusted to about pH 11 with a solution₂For example CuSO in the sol₄Is added.

【0008】

TiO₂When spraying the sol on the surface of the glaze layer 2, make sure that it is not completely buried. As a result, as shown in Fig. 2, TiO₂A part of the particle 3 enters the glaze layer 2, and the other part of the particle 3 is held in the glaze layer 2 in an exposed state.

【0009】

TiO₂By exposing a part of the particles 3, ultraviolet rays from a lamp fixed to a wall surface or the like (not shown) are TiO.₂The exposed portion of the particle 3 can be directly irradiated. And the ultraviolet rays are TiO₂When the particles 3 are irradiated, the adsorbed water reacts with the holes of the photocatalyst to form hydroxyl radicals (OH).^*) Is generated, and it is considered that the hydroxyl radical and ammonia react as shown in the following formula (1), and the hydroxyl radical and methyl mercaptan react as shown in the following formula (2) to deodorize.

【0010】

NH₃+ 3OH^* 1 / 2N₂+ 3H₂O (1) CH₃SH + OH^* CH₃S + H₂O 2CH₃S + 2OH^*+ 5O₂ 2CO₂+ 4H₂O + 2SO₂ ・・(2) 【0011】

3 to 6 are views showing another embodiment, and in the embodiment shown in FIG. 3, an ink layer 4 is formed by printing on the surface of the glaze layer 2, and TiO is formed on the surface of the ink layer 4.₂Particle 3 and Cu, Ag, etc. are sprayed so that a part thereof is exposed, and then heated and cooled in the same manner as described above.

【0012】

In the embodiment shown in FIG. 4, TiO is partially formed on the surface of the ink layer 4.₂Particles 3 and Cu, Ag, etc. are attached to form a pattern to enhance the decorative effect.₂Particles 3, Cu, Ag and the like may be formed on the surface of the glaze layer 2.

【0013】

In the examples shown in FIGS. 5 (a) and 5 (b), TiO is formed in the ceramic base 1 for the purpose of anti-slip or the like through the glaze layer 2.₂It retains particle 3 and Cu, Ag, etc. When the recess is formed in this way, dirt enters the recess and it is difficult to remove the dirt, but TiO₂By holding the particles 3, the dirt in the recess is decomposed, so that the dirt can be easily removed. In addition, by retaining Cu, Ag, etc., an antibacterial effect can be positively exerted.

【0014】

In the example shown in FIG. 6, the glaze layer 2 and TiO₂An ultraviolet reflective layer 8 made of thin-filmed aluminum powder, magnesia, etc. is interposed between the particles 3 and Cu, Ag, etc., and with such a configuration, once TiO₂Ultraviolet rays that have passed through the layer of particle 3 are again TiO₂Particles 3 can be irradiated, improving catalysis.

【0015】

Figure 7 shows CH₃It is a graph showing the result of testing the relationship between SH concentration and elapsed time for each heat treatment (firing) temperature. In the graph, τ1 / 10 shows the time until the concentration becomes 1/10, and the dotted line does not irradiate ultraviolet rays. Show the case. Also anatase type TiO₂The particles used had an average particle size of 100 Å.

【0016】

In addition, FIG. 8 is a graph showing the results of an experiment on the relationship between the heat treatment temperature and the odor removal rate after 30 minutes, and FIG. 9 is an anatase-type TiO with an average particle size of 500 Å.₂CH when using₃It is a graph which shows the relationship between SH concentration and elapsed time (heat treatment temperature; 700 ° C).

【0017】

The following can be said from these FIGS. 7, 8 and 9. First, anatase-type TiO in the presence of ultraviolet light₂Exhibits catalytic action. Secondly, the catalysis shows the maximum value around 700 ° C, and it is necessary to set the odor removal rate after 30 minutes to 50% or more and 300 ° C or more and less than 900 ° C. This is because activity is unlikely to occur when the heat treatment temperature is less than 300 ° C, and TiO when the heat treatment temperature exceeds 900 ° C.₂It is considered that the structure of anatase changes from anatase to rutile. Thirdly, it can be seen that anatase having a small particle size is good for catalysis.

【0018】

[Effect of the invention]

As described above, according to the present invention, copper or silver is contained as a metal having a bactericidal action in addition to titanium oxide in the glaze layer formed on the surface of the ceramic base material, so that the deodorizing effect due to the photocatalytic action is added. It can also exert an antibacterial effect.

[Simple explanation of drawings]

[Figure 1]

The figure which showed the manufacturing method of the ceramics having a photocatalytic function which concerns on this invention in the order of a process.

[Figure 2]

An enlarged cross-sectional view of the ceramic obtained by the same method.

[Fig. 3]

FIG. 5 is a cross-sectional view of a ceramic piece showing another embodiment.

[Fig. 4]

FIG. 5 is a cross-sectional view of a ceramic piece showing another embodiment.

[Fig. 5]

FIG. 5 is a cross-sectional view of a ceramic piece showing another embodiment.

[Fig. 6]

FIG. 5 is a cross-sectional view of a ceramic piece showing another embodiment.

[Fig. 7]

Anatase type TiO with an average particle size of 100 Å₂Elapsed time and CH when using₃The graph which shows the relationship with SH concentration.

[Fig. 8]

The graph which shows the relationship between the heat treatment temperature and the odor removal rate after 30 minutes.

[Fig. 9]

Anatase-type TiO with an average particle size of 500 Å₂Elapsed time and CH when using₃The graph which shows the relationship with SH concentration.

[Fig. 10]

FIG. 3 is a cross-sectional view of a ceramic having a photocatalytic function obtained by a conventional manufacturing method.

[Explanation of symbols]

1 ... Ceramic substrate, 2 ... Glaze layer, 3 ... TiO₂Particles, 4 ... ink layer, 6 ... water-soluble binder, 7 ... binder layer, 8 ... UV reflective layer, 100 ... wall material, 101 ... binder layer, 102 ... Photocatalytic particles.