JP2961892B2 - Method for producing antibacterial glaze for ceramics and method for producing antibacterial ceramics - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for producing an antibacterial glaze for ceramics such as sanitary ware and a method for producing an antibacterial ceramic.

BACKGROUND ART In general, the surfaces of sanitary ware such as toilets, washbasins, bidets and the like, or ceramics such as tiles are glazed to give a beautiful appearance of various colors to the ceramic surface, and a dense and water-repellent smooth layer (glaze) Layer) to provide a function for hygiene. Recently, in addition to the above-described functions, a high glare (including antifungal property and antifouling property) has been required for the glaze layer on the ceramic surface. One method of imparting antibacterial properties to the glaze layer is to apply an antibacterial agent to the surface of the glaze layer, but this method has poor durability and easily peels off. Therefore, the glaze is baked after mixing the antibacterial agent into the glaze.

In general, glaze is prepared by mixing water, glaze base material (the part to be vitrified by firing), pigment and binder,
High viscosity. And, since the viscosity is high, the antibacterial agent cannot be uniformly dispersed in the glaze, and it is impossible to achieve both durability and antibacterial property.

In addition, when the antibacterial agent is mixed and crushed alone in the glaze, the antibacterial agent itself is crushed, and the antibacterial effect is reduced. Furthermore, when the antibacterial agent is mixed with the glaze, the color of the glaze after firing (color of firing)
Is discolored. That is, when the glaze to which the antibacterial agent is added is fired, the antibacterial agent remaining in the matrix constituted by vitrification of the glaze base material has a dispersed structure, which is compared with the case where the antibacterial agent is not added. Then, the emulsification effect of the remaining antibacterial agent and a part of the antibacterial agent are melted into the glaze, and the coloration of the fired product changes. In many cases, when an antimicrobial agent is added, the color of the baked product changes in the direction of whitening.

Therefore, in order to obtain the same fired color when the antibacterial agent is added and when the antibacterial agent is not added, the composition and amount of the pigment are added when the glaze raw material is crushed and mixed. It is necessary to make it different when not.
This necessitates the use of two types of glazes (with and without an antibacterial agent) having different blending ratios for all glazes, and thus greatly reduces productivity.

On the other hand, as a prior art for imparting antibacterial properties to ceramic powder itself, there is one disclosed in Japanese Patent Application Laid-Open No. 4-234303.

In this prior art, a ceramic such as calcium phosphate, calcium hydrogen phosphate, calcium carbonate, calcium silicate, or hydroxyapatite is added to an aqueous solution containing a water-soluble salt of an antibacterial metal, and the antibacterial metal is added to the ceramic surface by heating. The amount of the antibacterial metal supported on the ceramic is 0.
It is described to be 01 to 20% by weight.

Therefore, as a prior art for imparting antibacterial properties to a glaze layer by mixing with a glaze while supporting an antibacterial metal of ceramic powder as in the above prior art, it is disclosed in JP-A-5-201747. There is something.

In this prior art, hydroxyapatite carrying an antibacterial metal is contained in a glaze, and the amount of antibacterial metal added to hydroxyapatite is 10%.
Hereinafter, it is described that the content is preferably 0.001% to 5%.

If only ceramic powder carrying antibacterial metal,
Since the surface is in contact with the outside air, sufficient antibacterial properties can be exhibited even when the amount of the antibacterial metal carried on the ceramic is about 0.01% by weight, but the antibacterial metal as disclosed in JP-A-4-234303 is disclosed. When the ceramic powder carrying lime is mixed with the glaze to provide antibacterial properties to the glaze layer on the surface of sanitary ware, enamel or tile, most of the ceramic powder is buried in the glaze Cannot exhibit antibacterial properties.

Also, with the amount of antibacterial metal added as disclosed in JP-A-5-201747, the desired antibacterial properties cannot be exhibited synchronously.

Therefore, in order to impart sufficient antibacterial properties to the glaze layer, it is conceivable to mix a large amount of ceramic powder carrying an antibacterial metal with the glaze. The change causes a lack of melting.

When silver is selected as the antibacterial metal, it exhibits antibacterial properties about 1/10 of other metals, for example, copper and zinc. , Detracting from the value of the glaze layer.

DISCLOSURE OF THE INVENTION The present invention has been made in view of the above problems, and its purpose is to provide an antibacterial glaze,
It is to provide antibacterial property and durability to the surface of a product such as a ceramic or an enamel.

Therefore, the method for manufacturing an antibacterial glaze for ceramics according to the present invention basically comprises mixing and pulverizing water, a glaze base material, and a pigment to form a base glaze, and carrying the antibacterial metal on the base glaze. And then mixing the binder.

Further, by adding an antibacterial agent to the glaze, the color of the fired color changes as compared with the case where the antibacterial agent is not added. In order to improve or prevent this, the method for producing an antibacterial glaze for ceramics according to the present invention comprises, as an alternative, mixing and pulverizing water, a glaze base material and a pigment to form a base glaze. In addition, heat-resistant powder carrying an antimicrobial metal, and a pigment whose firing color changes in a direction opposite to the direction in which firing color changes by the addition of the heat-resistant powder are mixed, and then a binder is mixed. It is possible to construct from.

The heat-resistant powder preferably has an average particle size of 1 μm or more and 15 μm or less. The amount of the antibacterial metal carried on the heat-resistant powder is preferably 0.5% by weight or more and 25% by weight or less. Further, the amount of the heat-resistant powder carrying the antibacterial metal is preferably 0.5% by weight or more and 10% by weight or less based on the dry weight of the glaze.

Further, as a more specific example of the antibacterial member according to the present invention, silver is used as the antibacterial metal and ceramic powder is used as the heat-resistant powder. The antibacterial member obtained thereby has a ceramic powder carrying silver added to the glaze, and the ratio of silver to the total weight of the silver and the ceramic powder is 10% by weight or more, and the silver The ratio to the glaze layer is less than 1% by weight.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic enlarged cross-sectional view of a surface portion of a ceramic according to a first embodiment of the present invention, and FIG. 2 is a surface layer of the ceramic when two layers are mounted according to a second embodiment of the present invention. It is a typical expanded sectional view of a part.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, a method for producing an antibacterial ceramic glaze and a method for producing an antibacterial ceramic according to the present invention will be described in detail.

In the method for producing an antibacterial glaze for ceramics according to the present invention, basically, water, a glaze base material and a pigment are mixed and pulverized to form a base glaze, and the base glaze carries a heat-resistant antibacterial metal. Mixing the powder and then mixing the binder.

As the antibacterial metal, silver, copper, zinc or the like having an oligodynamic effect is used, and silver is particularly excellent in antibacterial property.

In addition, it is necessary that the heat-resistant powder does not completely decompose and melt at the firing temperature of ceramics or the like, and a calcium phosphate-based compound such as hydroxyapatite, or a calcium phosphate-based compound and a feldspar-like flux are sintered. Use those that have been used.

Further, as the glaze, a known glaze for ordinary ceramics can be used. The main component of the glaze is a glaze base material that is hung on glass after firing. As the glaze base material, a frit (frit glaze) hung on glass from the beginning may be used, or raw materials that are vitrified by firing ( Raw glaze) may be used. Raw materials include, for example, quartz sand in sanitary ware,
Alumina, clays, feldspars, limes, wollastonite, zinc white, dolomite and the like are used.

Examples of glaze materials other than the glaze base material include various pigments for coloring and emulsifiers such as zircon and tin oxide added as needed.

Further, examples of the binder include carboxymethyl, cellulose sodium salt, methylcellulose, various natural rubbers, polyvinyl alcohol, and the like. If necessary, a deflocculant, a flocculant, a decay inhibitor and the like may be added.

In addition, when mixing the heat-resistant powder carrying the antibacterial metal with the base glaze, water may be added to suppress a rise in temperature.

Furthermore, in the industrial glaze process, a considerable part of the glaze used is collected without adhering to the workpiece.
Then, the recovered glaze is used by being mixed with a newly prepared glaze (new glaze). In this case, since the recovered glaze contains a binder and has a high viscosity, it is preferable to mix the heat-resistant powder supporting the antibacterial metal on the new glaze.

The heat-resistant powder carrying the antibacterial metal was not directly mixed with the base glaze, but a part of the base glaze was taken out, and the heat-resistant powder carrying the antibacterial metal was mixed with the base glaze thus taken out. The mixture may be returned to the base glaze.

In addition, the manufacturing method for the antibacterial glaze for ceramics described above was partially modified, and water, a glaze base material, and a pigment were mixed and pulverized to form a base glaze. It is also possible to mix the powder and a pigment whose firing color changes in a direction opposite to the direction in which the firing color changes by the addition of the heat resistant powder, and then mix the binder.

Here, the pigment added to the base glaze to change the firing color may be the same as the pigment constituting the base glaze. Further, it is preferable that the pigment to be mixed in preparing the base glaze is 70% or more of the total pigment added to the ceramic glaze. If this ratio is less than 80%, there is a possibility that uniform dispersion of the pigment to be added later may be hindered.

Furthermore, in the above-described method for producing an antibacterial glaze for ceramics, a part of the base glaze is taken out, and the base glaze thus taken out is added with a heat-resistant powder carrying an antibacterial metal and the heat-resistant powder. It is also possible to mix a pigment whose firing color changes in the direction opposite to the firing color changing direction, and to return this mixture to the base glaze.

The average particle size of the heat-resistant powder is 1 μm to 15 μm
m or less. If it is smaller than 1 μm, it tends to aggregate and uniform dispersion becomes difficult. Also
If it exceeds 15 μm, sufficient antibacterial properties cannot be expected.

The amount of the antimicrobial metal carried on the heat-resistant powder is preferably 0.5% by weight or more and 25% or less. If the amount is less than 0.5% by weight, sufficient antibacterial properties cannot be obtained.
If it is more than 5% by weight, it becomes difficult to support the powder on the heat-resistant powder. The amount of the heat-resistant powder carrying the antibacterial metal is 0.5% by weight or more based on the dry weight of the glaze.
It is preferably 0% by weight or less. If the amount is less than 0.5% by weight, sufficient antibacterial properties cannot be obtained. If the amount is more than 10% by weight, the viscosity of the glaze at the time of firing becomes too large, and the glaze surface deteriorates.

Further, in the method for manufacturing an antibacterial ceramic according to the present invention, the antibacterial glaze obtained by the above-described method for manufacturing an antibacterial glaze for ceramic is applied to a ceramic substrate and then fired.

The above-mentioned method for producing antibacterial porcelain is partially modified, and a base glaze is obtained by mixing and pulverizing water, a glaze base material, and a pigment, and mixing the base glaze with a binder. It is also possible to apply a ceramic glaze obtained by the above-mentioned method for producing an antibacterial glaze for ceramics according to the present invention, and then to bake.

The resulting antibacterial porcelain is composed of a base glaze layer as a lower glaze layer, an antibacterial glaze layer as an upper layer, and a base glaze layer comprising a mixture of water, a glaze base material and a pigment. The antibacterial glaze layer is an antibacterial mixture of a heat-resistant powder that carries an antibacterial metal on a base glaze and a pigment that changes the firing color in the direction opposite to the direction in which the firing color changes when the heat-resistant powder is added. It consists of a glaze.

Next, a description will be given of a first embodiment of a method for producing the above-described antibacterial glaze for ceramics according to the present invention, and a method for producing an antibacterial ceramic using the antibacterial glaze for ceramics, with reference to the accompanying drawings.

FIG. 1 is a schematic enlarged sectional view of a surface layer portion of an antibacterial ceramic according to a first embodiment of the present invention. The antibacterial ceramic has a glaze layer 2 formed on a surface of a substrate 1. Contains heat-resistant powder 3.
Antimicrobial metals 4 are supported as antimicrobial agents on the surface of the substrate.

The ceramic shown in FIG. 2 is manufactured in a two-layered manner, and a normal glaze layer 5 having no antibacterial property is formed on the substrate 1.
The glaze layer 2 is formed by mixing the heat-resistant powder 3 carrying the antibacterial metal 4 on the glaze layer 5.

To prepare the glaze forming the glaze layers 2 and 5, the water, most of the glaze base material and the pigment, and if necessary, the emulsifier are desired using a cylinder mill, a pot mill, a vibration mill, or the like. The base glaze is ground to a particle size of.

Next, an antibacterial agent (heat-resistant powder carrying an antibacterial metal) and the remaining portion of the pigment are mixed with the above glaze. If the expected color of the baked product is whitish, the color of the baked product hardly changes even if a heat-resistant powder carrying an antibacterial metal is added. Therefore, when preparing the base glaze, all of the pigment is added. You may do so.

As a mixing device, a homogenizer, a plunger, a constrained stirrer, or the like is used in addition to the various mills used for preparing the base glaze.

Next, a binder is mixed with the base glaze to produce an antibacterial glaze for ceramics. Various agitators can be used for this purpose, and if the lot is small, a hand mixer is sufficient.

The antibacterial glaze for ceramics obtained as described above is applied to, for example, a green sanitary ware that has been dried after molding. As a method of application, spraying, dipping, brushing, or the like is used.

The method of glazing may be either single-layer or double-layer. The advantage of the two-layer coating is that it takes more time than a single-layer coating, but when the antibacterial metal is very expensive, the amount used can be reduced.

Next, the green body after the completion of the glaze is fired. The firing conditions (heat curve, firing atmosphere, etc.) are preferably the same as those of a conventional product coated with a glaze that does not contain an antibacterial agent, since they can be mixed and loaded in the same kiln. For that purpose, as described above, the color of the sintering is matched between those containing the antibacterial agent and those without the antibacterial agent (matching the sintering color presupposes that the sintering conditions are the same). In addition, the viscosity (fluidity) of the glaze at the time of firing may be matched.

Next, specific Examples 1 to 3 will be described. First, Table 1 below
Shows the glaze base material and the components of the antibacterial agent used in Examples 1 to 3. As the pigment, a general metal oxide compound such as iron oxide and tin oxide was used, and as the binder, general carboxymethyl cellulose (CMC) was used.

(Example 1) A. Base glaze preparation Glaze base material 100 parts ZrO ₂ 7 parts (ZrO ₂ is added for adjusting the turbidity of glaze) Red pigment 1.5 parts Blue pigment 0.3 parts Yellow pigment 0.3 parts Glaze mixture with antibacterial agent Base glaze 100 parts Red pigment 1.0 part Blue pigment 0.2 parts Yellow pigment 0.3 parts Antibacterial agent 3 parts (Example 2) A. Base glaze mixture Glaze base material 100 parts Blue pigment 5 parts Green Pigment 1.5 parts B. Glaze mixed with antibacterial agent Base glaze 100 parts Blue pigment 1.0 parts Green pigment 0.1 parts Black pigment 0.5 parts Antibacterial agent 2 parts (Example 3) A. Base glaze mixture Glaze base material 100 parts ZrO ₂ 5 parts (ZrO ₂ is added to adjust the turbidity of the glaze) Gray pigment 3 parts Red pigment 1 part Blue pigment 0.5 part B. Glaze preparation mixed with antibacterial agent Base glaze 100 parts Antibacterial agent 1 part After adding a binder to the base glaze and the glaze mixed with the mixture prepared in Examples 1 to 3, the surface of the sanitary ware green body was glazed and fired, and then each of the examples was used. For confirmed coloration visually and colorimetric device.

There was no difference in visual coloration. In addition, there was no problem in the color value difference (ΔE ^* _ab ) in the measurement result by the colorimeter.

Table 2 below shows the results of colorimetry performed by the colorimeter. Table 2
The results are based on (CIE1976) L ^* , a ^* , b ^* color difference of JIS Z8105 (No. 2070). Here, L ^* : lightness index a ^* , b ^* : chromaness posture (two coordinates representing a position in an equal lightness plane in a uniform color space) ΔE ^* _ab : coordinate L in the L ^* a ^* b ^* color system ^* , A ^* , b
^* Difference ΔL ^*, Δa ^*, Δb ^* color difference ΔE between two color stimuli defined by _{^{* ab = [(ΔL *)}} 2 + (Δa *) 2) + (Δb
^* ) ² ] ^1/2 Table 3 below shows the antibacterial evaluation of the ceramics manufactured using the antibacterial glaze for ceramics according to the first example.
For evaluation of antibacterial activity, E. coli ( Echerichia coli)
W3110 strain). 0.15 ml of bacterial solution (10.000-15,000) is applied to the glaze surface of the sample that has been sterilized with 70% ethanol
CFU) was dropped, placed on a glass plate (100 × 100 mm), brought into close contact with the glaze surface of the sample, allowed to stand for 3 hours, and then the bacterial solution of the sample was wiped off with sterile gauze and collected in 10 ml of saline solution. The survival rate of the bacteria was determined and used as an index for evaluation. The evaluation criteria are shown below.

++: Escherichia coli survival rate of less than 10% ++: Escherichia coli survival rate of 10% or more and less than 30% +: Escherichia coli survival rate of 30% or more and less than 70%-: Escherichia coli survival rate of 70% or more As described above, according to the present invention, when preparing a base glaze of an antibacterial glaze, a binder is not added, and a binder is mixed after mixing a heat-resistant powder carrying an antibacterial metal in the base glaze. Therefore, the antibacterial agent is mixed with the low-viscosity base glaze, so that uniform dispersion can be performed, and therefore, both durability and antibacterial property can be achieved.

In addition, since the antibacterial metal was not mixed alone, but was mixed in a state where the antibacterial metal was supported on the heat-resistant powder,
The antibacterial agent itself is not crushed, and the antibacterial cost can be increased.

Furthermore, when the heat-resistant powder carrying the antibacterial metal is mixed with the base glaze, a pigment whose firing color changes in the direction opposite to the direction in which the firing color is added due to the addition of the heat-resistant powder is mixed. Thus, the same baked color can be obtained when the antibacterial agent is contained and when there is no antibacterial agent.

In addition, a part of the base glaze is taken out, a heat-resistant powder carrying an antibacterial metal on the base glaze, and a pigment whose firing color changes in a direction opposite to the direction in which firing color changes due to the addition of the heat-resistant powder. If this mixture is returned to the base glaze, the amount of the base glaze for mixing the heat-resistant powder carrying the antibacterial metal and the pigment is small, so that a large-scale mixing device is not required. .

Next, a method for producing an antibacterial glaze according to a second embodiment of the present invention, an antibacterial member using the glaze, and a method for producing the same will be described using experimental examples.

In the second embodiment, silver is used as the antibacterial agent and ceramic powder is used as the heat-resistant powder. In the antibacterial member according to the second embodiment, a glaze layer is formed on the surface of the member, and a ceramic powder carrying silver is added to the glaze layer. And the proportion of silver to the total weight of 10% by weight or more,
The ratio of the silver to the glaze layer was less than 1% by weight.

Here, as long as the material of the base material has heat resistance to the melting temperature of the glaze, any material such as ceramic, enamel, tile, ceramic, glass, metal, or a composite thereof can be used. The shape of the material is not limited to a simple shape such as a sphere, a column, a cylinder, a plate, etc.
It may be of a complicated shape such as a sink or tableware.

The ceramic powder has an average particle size of 10 μm.
Use less than Specific materials include calcium phosphate, calcium hydrogen phosphate, hydroxyapatite, phosphate compounds such as aluminum phosphate, aluminosilicates such as zeolite, silicates such as montmorillonite, calcium carbonate, zinc oxide and the like. .

Particularly, for sanitary ware, phosphate compounds, calcium carbonate, calcium silicate, zinc oxide and the like are preferable because they are fired at 1000 ° C. or higher.

In the second embodiment, silver as a relatively therapeutic antibacterial metal is supported on the surface of the ceramic powder, and this ceramic powder is mixed into the glaze to reduce the amount of the antibacterial agent added. It is possible to enhance antibacterial properties without impairing properties.

Next, the second embodiment will be described more specifically using an experimental example.

Example 4 A 50 mm × 100 mm plate-like test piece was prepared using a slurry of a sanitary ware body prepared using silica sand, feldspar, clay and the like as raw materials.
On the other hand, a predetermined amount of calcium phosphate powder having an average particle size of 2 μm carrying a predetermined amount of silver is added to a blue glaze and mixed in water,
This mixture was applied to the plate-shaped test piece and fired at 1100 to 1200 ° C. to obtain a sample. The antibacterial properties of the obtained samples were evaluated.

Here, the composition of the glaze is as follows. The pigment used was an ordinary metal oxide pigment. Further, a predetermined amount of carboxymethylcellulose (CMC) may be added to the glaze as a glue, if necessary.

SiO _2: 55 to 80 wt% Al ₂ O _3: 5~13 wt% Fe ₂ O _3: 0.1~0.4 wt% l MgO: 0.8 to 3.0 wt% CaO: 8 to 17 wt% ZnO: 3 to 8 wt% K ₂ O: 1 to 4 wt% Na ₂ O: 0.5 to 2.5 wt% ZrO _2: 0 to 15 wt% pigment (blue): 1-20 wt% addition, the component composition of the silver was supported calcium phosphate-based powder Is shown below.

SiO _2: 20 to 60 wt% Al ₂ O _3: 5~20 wt% Fe ₂ O _3: 0~5.0 wt% l MgO: 0 to 5.0 wt% CaO: 10 to 40 wt% ZnO: 0 to 5.0 wt% K ₂ O: 0.1 to 4.0 wt% Na ₂ O: 0.1 to 2.0 wt% P ₂ O _5: 10~40 wt% Ag: about 0.1 to 30 wt% antimicrobial evaluation, E. (Ecshrichia coli W3
(110 strains). The test method is as follows: 0.15 ml of bacterial solution (10,000-
50,000 CFU) was dropped, placed on a glass plate (100 × 100), adhered to the outermost surface of the substrate, and then left for 3 hours. Then, the bacterial solution of the sample was wiped with sterile gauze and collected in 10 ml of physiological saline. The survival rate of the bacteria was determined and used as an index for evaluation. The evaluation criteria are as follows, and the results are shown in the following table.

++: Escherichia coli survival rate of less than 10% ++: Escherichia coli survival rate of 10% or more and less than 30% +: Escherichia coli survival rate of 30% or more and less than 70%-: Escherichia coli survival rate of 70% or more As shown in Table 4, the antibacterial property is improved by increasing the amount of silver carried per calcium phosphate powder in the glaze, and is 10% by weight.
This is +++. In addition, the total amount of silver is 1
It was found that the color of the original glaze could not be obtained when the weight% was exceeded.

The following 2 reasons why the antibacterial property is improved when the amount of the pigment carried per calcium phosphate-based powder in the glaze is increased.
One can be considered.

First, as the first reason, in the method of kneading a glaze and a calcium phosphate-based powder and applying the mixture on a substrate as described above, many calcium phosphate-based powders are buried in the glaze layer. Exists near the surface layer. When the ratio is considered to be almost constant, it is considered that it is advantageous to attach a large amount of silver, which is an antibacterial agent, to one particle, and the second reason is that a small amount of silver is added to the calcium phosphate powder. If not supported, silver is too strongly fixed to the calcium phosphate-based powder and the antibacterial effect is small, and by supporting a large amount of silver, the fixation to the calcium phosphate-based powder is moderately loosened and the antibacterial effect is thought to increase. Can be

Example 5 A 50 mm × 100 mm plate-shaped test piece was prepared using a slurry of a sanitary ware body prepared using silica sand, feldspar, clay and the like as raw materials.
On the other hand, a predetermined amount of calcium phosphate powder having an average particle size of 2 μm carrying a predetermined amount of silver is added to a brown glaze and mixed in water,
This mixture was applied to the plate-shaped test piece and fired at 1100 to 1200 ° C. to obtain a sample. The antibacterial properties of the obtained samples were evaluated. The criteria for the antibacterial evaluation were the same as in Example 4 above, and the results are shown in Table 5 below. The composition of the glaze and the calcium phosphate powder were the same except for the type of pigment.

From Table 5, it was found that the antibacterial property was improved when the amount of silver supported per calcium phosphate-based powder in the glaze was increased, and good results were obtained with ++ at 10% by weight or more and +++ at 15% by weight or more.

Example 6 A plate-shaped test piece of 50 mm × 100 mm was prepared using a slurry of sanitary ware body prepared using silica sand, feldspar, clay and the like as raw materials,
On the other hand, calcium phosphate-based powder having a predetermined particle size carrying 10% by weight of silver was added to ivory glaze at 2.5% by weight and mixed in water, and the mixture was applied to the plate-like test piece,
A sample was obtained by firing at 1200 ° C. The antibacterial properties of the obtained samples were evaluated. The criteria for the antibacterial evaluation were the same as in Example 4 above, and the results are shown in Table 6 below. The composition of the glaze and the calcium phosphate powder were the same except for the type of pigment.

According to Table 6, when the particle size of the calcium phosphate-based powder was 2 μm or 6 μm, the antibacterial property showed a good result of ++ or ++, but deteriorated to + at 10 μm. This is considered to be because when the particle size of the calcium phosphate-based powder is large, the glaze is likely to settle during melting, and the amount of silver existing near the surface is reduced.

As described above, according to the second embodiment, in the antibacterial member having the glaze layer formed on the substrate surface, silver is selected as a metal capable of exhibiting antibacterial properties even in a small amount, and this silver is added to the glaze layer. Since the proportion is less than 1% by weight, the glaze layer is not colored brown or black.

Further, even if the addition ratio of silver to the glaze layer is reduced to less than 1% by weight, the amount of silver supported on the total weight of the ceramic powder and silver contained in the glaze is set to 10% by weight or more. Sufficient antibacterial properties can be exhibited.
In particular, when the silver loading is 15% by weight or more, the initial antibacterial property can be exhibited even when impregnated in a glaze containing a trace amount of interfering components.

In this way, by increasing the amount of silver carried on the ceramic powder, the amount of ceramic mixed with the glaze can be reduced, and therefore, the discoloration of the glaze layer after firing and the change in the properties of the glaze can be suppressed. it can. Further, when the average particle size of the ceramic powder is less than 10 μm, the amount of silver exposed on the surface layer of the glaze layer increases, so that a small amount of silver can exhibit sufficient antibacterial properties.

Continuation of the front page (72) Inventor Satoshi Horiuchi 2-1-1 Nakajima, Kokurakita-ku, Kitakyushu-shi, Fukuoka Touchi Kikai Co., Ltd. (72) Mitsuyoshi Machida 2-1-1 Nakajima, Kokurakita-ku, Kitakyushu-shi, Fukuoka No. 1 Toto Kiki Co., Ltd. (56) References JP-A-6-340513 (JP, A) JP-A-5-201747 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) ) A01N 59/16 C03C 8/00

Claims (16)

(57) [Claims] 1. Mixing and pulverizing water, a glaze base material and a pigment to form a base glaze, mixing a heat-resistant powder carrying an antibacterial metal with the base glaze, and then mixing a binder. A method for producing an antibacterial glaze for ceramics comprising: 2. The base glaze according to claim 1, wherein a part of the base glaze is taken out, the heat-resistant powder carrying the antibacterial metal is mixed with the base glaze taken out, and the mixture is returned to the base glaze. A method for producing an antibacterial glaze for ceramics, the method comprising: 3. The method according to claim 1, wherein the heat-resistant powder has an average particle size of 1 μm or more and 15 μm or less. 4. The method according to claim 1, wherein the amount of the antibacterial metal supported on the heat-resistant powder is 0.5% by weight or more and 25% by weight or less. 5. The method according to claim 1, wherein the amount of the heat-resistant powder supporting the antibacterial metal is based on the dry weight of the glaze.
A method for producing an antibacterial glaze for ceramics, comprising from 0.5% by weight to 10% by weight. 6. A base glaze obtained by mixing and pulverizing water, a glaze base material and a pigment, and adding a heat-resistant powder carrying an antibacterial metal to the base glaze and adding the heat-resistant powder. A method for producing an antibacterial glaze for ceramics, comprising mixing a pigment whose firing color changes in a direction opposite to the firing color changing direction, and then mixing a binder. 7. The antibacterial property for ceramics according to claim 6, wherein the pigment mixed with the base glaze to change the sintering coloration is the same as the pigment constituting the base glaze. How to make glaze. 8. The method for producing an antibacterial ceramic glaze according to claim 6, wherein the pigment constituting the base glaze is 70% or more of the total amount of the pigment added to the ceramic glaze. 9. The method according to claim 6, wherein a part of said base glaze is taken out, said heat-resistant powder carrying said antibacterial metal is added to said base glaze taken out, and baked by adding said heat-resistant powder. A method for producing an antibacterial glaze for ceramics, comprising mixing a pigment whose firing color changes in a direction opposite to the direction in which the color changes, and then mixing a binder. 10. The method according to claim 6, wherein the heat-resistant powder has an average particle size of 1 μm or more and 15 μm or less. 11. The method according to claim 6, wherein the amount of the antibacterial metal supported on the heat-resistant powder is 0.5% by weight or less and 25% by weight.
A method for producing an antibacterial glaze for ceramics comprising: 12. The antibacterial property for ceramics according to claim 6, wherein the amount of the heat-resistant powder supporting the antibacterial metal is 0.5% by weight or more and 10% by weight or less based on the dry weight of the glaze. How to make glaze. 13. Mixing and pulverizing water, a glaze base material and a pigment to form a base glaze, mixing a heat-resistant powder carrying an antibacterial metal with the base glaze, and then mixing a binder. A method for producing an antibacterial porcelain, which comprises applying an antibacterial glazing for porcelain produced from a ceramic substrate to a porcelain body, followed by firing. 14. The method according to claim 13, wherein water, a glaze base material, and a pigment are mixed and pulverized to form a base glaze, and a mixture of the base glaze and a binder is applied to the ceramic body. A method for producing an antibacterial ceramic, comprising applying the antibacterial glaze for ceramic. 15. A base glaze obtained by mixing and pulverizing water, a glaze base material and a pigment, and adding a heat-resistant powder carrying an antibacterial metal to the base glaze and adding the heat-resistant powder. An antibacterial glaze for ceramics manufactured by mixing a pigment whose firing color changes in a direction opposite to the firing color changing direction, and then mixing a binder, is applied to the ceramic substrate, and then fired. A method for producing an antibacterial porcelain. 16. The ceramic base material according to claim 15, wherein water, a glaze base material, and a pigment are mixed and pulverized to form a base glaze, and a mixture of the base glaze and a binder is applied to the ceramic body. A method for producing antibacterial porcelain, which comprises applying an antibacterial glaze for porcelain.