JP2003002771A - Substrate treating composition for antibacterial glaze, antibacterial article using the same and its manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a composition for a substrate layer which is effective to reveal antibacterial property of an antibacterial article having a glaze layer containing an antibacterial agent with high efficiency, at a low cost, simply and uniformly and to provide the antibacterial article using the same and its manufacturing method. SOLUTION: The substrate layer (preferably having 10 to 500 μm thickness) is formed on a base body of the antibacterial article by applying a substrate layer coating liquid containing a composition incorporating 75 to 90 wt.% SiO2 , 10 to 20 wt.% Al2 O3 and 0.1 to 3 wt.% K2 O+Na2 O and drying. Then the glaze layer containing the antibacterial agent (preferably silver or a silver compound) is formed thereon and is fired.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an antibacterial glaze base treatment composition, an antibacterial article using the same, and a method for producing the same. To elaborate further,
The present invention is mainly for tiles, sanitary ware, porcelain, ceramics such as tableware, enamel products and the like, when glazeing with an antibacterial glaze, a composition for surface treatment of the substrate surface, and an antibacterial property obtained by using the composition. The present invention relates to an article and a method for producing the same, in which the base treatment composition of the present invention is applied to a base material in advance and treated, and a high antibacterial property is obtained by applying an antibacterial glaze containing an antibacterial agent on the base. It is possible to obtain an antibacterial article having. The present invention relates to the composition for base treatment, an antibacterial article produced by using the composition, and a method for producing the same.

[0002]

2. Description of the Related Art In recent years, many antibacterial products have been developed due to increasing cleanliness. This tendency is also seen in ceramic products such as sanitary ware, tiles and enamel, and antibacterial sanitary ware, tiles, porcelain plates, tableware, enamel and other antibacterial articles have been commercialized. The antibacterial agents used in these ceramic products are mainly powdered inorganic silver antibacterial agents, and the antibacterial agents are used by being mixed in glazes.

However, when the antibacterial agent is used by being mixed in the glaze, the antibacterial agent is distributed in the entire glaze layer.
This means that the antibacterial agent is distributed not only on the surface of the glaze layer that exhibits an antibacterial effect, but also on the bottom of the glaze layer that does not actually appear on the surface. Further, since part of the silver component in the glaze layer is volatilized during the firing step, not all of the compounded antibacterial agent remains in the glaze layer.

On the other hand, there is known a method of performing the glaze process in several stages, that is, a multilayer glaze method. In this method, the antibacterial agent may be mixed only in the uppermost glaze layer.

However, even in this case, the silver in the uppermost glaze layer diffuses throughout the glaze layer below. Furthermore, in any of the glaze methods, part of the silver in the glaze layer diffuses into the base material. As a result, the content of silver that contributes to the antibacterial property in the antibacterial ceramic product decreases as compared with the amount charged in the glaze solution, and there is a problem that the silver is wasted.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in order to efficiently solve the problems of the above-mentioned conventional techniques, and the problems specifically set for that purpose are as follows.
An object of the present invention is to provide an undercoating composition which effectively and simply imparts uniform antibacterial property at low cost, an antibacterial article using the same, and a method for producing the same.

[0007]

Means for Solving the Problems The antibacterial glaze base treatment composition of the present invention comprises SiO ₂ of 75 to 90%, Al ₂ O ₃ of 10 to 20%,
It is characterized by containing 0.1 to 3% of K ₂ O and Na ₂ O in total. The antibacterial article of the present invention has a base layer, which is formed on the surface of a substrate, containing the antibacterial glaze base treatment composition of the present invention, and a glaze layer containing an antibacterial agent is glazed on the base layer. It is characterized by that. In the antibacterial article of the present invention, it is preferable that the antibacterial agent contains silver or a silver compound. In the antibacterial article of the present invention, the antibacterial glaze base treatment composition-containing base layer preferably has a thickness of 10 to 500 μm. The method for producing an antibacterial article of the present invention comprises applying a slurry containing the antibacterial ceramic undercoating composition of the present invention to a surface to form a base layer, and glazeing a glaze containing an antibacterial agent thereon. It is characterized by firing to form a glaze layer. In the method for producing an antibacterial article of the present invention, it is preferable that the antibacterial agent contains silver or a silver compound.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION In carrying out the present invention, for example, when the substrate of the antibacterial article is ceramics, first, 75 to 90% by weight of SiO ₂ and Al ₂ O ₃ are formed on a dry substrate substrate or an unglazed substrate substrate.
10 to 20% by weight, and the total amount of K ₂ O and Na ₂ O is 0.1.
Water is added to the base treatment composition containing 3% by weight to form a slurry. This slurry is applied onto a substrate by a commonly used method such as a spray coating method, a flow coating method, or a dipping coating method, and dried if necessary to form a base layer. Thereafter, a glaze slurry containing an appropriate amount of an antibacterial agent is glazed by a method such as a spray coating method, a flow coating method or a dipping coating method in the same manner as the coating method, dried, and baked to form a glaze layer. To do. The antibacterial agent is not particularly limited, but an inorganic antibacterial agent,
In particular, it is preferable to use a silver antibacterial agent containing silver or a silver compound. After glazing and drying, the glaze firing temperature usually used, that is, 800 ° C, depending on the type and application of the glaze
Bake at a temperature of ~ 1300 ° C. As a result, an antibacterial ceramic product exhibiting an antibacterial effect can be obtained with high efficiency. A preferable firing temperature is 1000 ° C to 1300 ° C.

The surface treatment composition used here contains 75 to 90% by weight of SiO ₂ , 10 to 20% by weight of Al ₂ O ₃ , and K ₂ O.
And Na ₂ O are 0.1 to 3 wt%, preferably SiO ₂ is 80 to 85 wt%, Al ₂ O ₃ is 12 to 18 wt%,
The total amount of K ₂ O and Na ₂ O is 0.5 to 2.5% by weight. When the content of SiO ₂ in the undercoating composition is less than 75% by weight, the undercoat layer is completely melted together with the glaze layer during firing, and the effect of the undercoat layer is lost, and when it exceeds 90% by weight. It is not melted at all during firing, and warpage of the substrate, indentation of the glaze surface, cracking and peeling occur. If the content of Al ₂ O ₃ in the undercoating composition is less than 10% by weight, the composition crystallizes and becomes emulsified. On the other hand, if it exceeds 20% by weight, the content of SiO ₂ becomes relatively insufficient and the above-mentioned inconvenience occurs. When the total content of K ₂ O and Na ₂ O in the base treatment composition exceeds 3% by weight, the base layer melts together with the glaze layer formed thereon during firing, and the antibacterial agent in the glaze layer is formed. , For example, silver diffuses through the underlayer into the substrate, reducing the concentration of antibacterial agents, such as silver, in the glaze layer. The base treatment composition of the present invention has the effect of ensuring the antibacterial agent component in the glaze in the glaze layer without diffusing into the substrate. Further, the undercoating composition of the present invention may be constituted by blending natural products such as kaolin, feldspar, and silica stone so as to have a predetermined composition, or may be synthesized by an appropriate method.

In the antibacterial substance layer of the present invention, the thickness of the underlayer formed by the undertreatment composition of the present invention is preferably 10 to 500 μm after firing, 30
To 400 μm is more preferable, and 50 to 20
More preferably, it is 0 μm. Underlayer thickness is 10
When the thickness is less than μm, the underlayer is thin, so that the diffusion of the antibacterial agent in the glaze layer, such as silver, into the substrate cannot be sufficiently prevented. Further, when it exceeds 500 μm, the surface coating layer consisting of the underlayer and the glaze layer becomes excessively thick,
Not only does it impair the aesthetics, but it also costs more than necessary. Further, when the thickness of the underlayer is 50 to 200 μm, diffusion of the antibacterial agent into the substrate is effectively prevented without impairing the original color tone of the glaze and the designability (aesthetic appearance), and the obtained glaze layer is , Exert more effective antibacterial effect.

The composition of the glaze with which the antibacterial agent is mixed in the antibacterial article of the present invention and the method for producing the same is not particularly limited as long as it can be baked at a temperature of 800 to 1300 ° C., and it depends on the use of the article. Thus, a conventional composition can be used. For example, a zircon glaze containing 4 to 15% ZrO ₂ and a lime glaze containing 5 to 20% CaO can be used. There is no limitation on the thickness of the glaze layer, for example, 50 to
It can be appropriately set within the range of 1000 μm.

The antibacterial article of the present invention has the structure shown in FIG. In FIG. 1, a base layer 2 is formed on the surface of a substrate (base material) 1, and an antibacterial agent-containing glaze layer 3 is formed thereon. In the antibacterial article of the present invention, the diffusion of the antibacterial agent in the glaze layer 3 into the substrate 1 due to the baking treatment is prevented by the underlayer having a specific composition.

[0013]

The present invention will be further described with reference to the following examples. However, the technical scope of the present invention is not limited to these examples.

Example 1 To prepare a surface treating composition according to the present invention, SiO ₂ was added.
49.7% by weight, Al ₂ O ₃ 34.6% by weight, K ₂ O and Na ₂ O total 0.8% by weight (the remaining amount is an impurity, hereinafter the same) 10 parts by weight of clay and SiO ₂ 82.0% by weight, Al ₂ O ₃ = 16.
85 parts by weight of kaolin whose total amount of K ₂ O and Na ₂ O is 2.0% by weight, 54.0% by weight of SiO ₂ and 4% by weight of Al ₂ O ₃
3.0% by weight and 5 parts by weight of calcined kaolin having a total amount of K ₂ O and Na ₂ O of 0.7% by weight were mixed. This mixture 60
40 parts by weight of water was added to parts by weight, and the resulting slurry was treated with a planetary mill for 20 minutes. The obtained slurry was used as a base layer coating liquid. This coating solution was spray-coated on the surface of the plate-shaped ceramic base using a spray gun, and dried at room temperature. Next, a slurry of zircon glaze containing 2% by weight of an inorganic antibacterial agent having a silver content of 25% by weight was glazed on the underlayer and dried at room temperature. This was fired according to a firing program in which the temperature was kept at 1200 ° C for 2 hours to obtain an antibacterial pottery. The thickness of the base layer after firing was 150 μm, and the thickness of the glaze layer was 250 μm.

Example 2 To prepare a surface treatment composition according to the present invention, SiO ₂ was used to prepare it.
98.6% by weight, 0.6% by weight of Al ₂ O _3, 5 parts by weight of silica containing 0.3% by weight of K ₂ O and Na ₂ O, 82.0% by weight of SiO ₂ and 16.0% by weight of Al ₂ O _3. %, The total amount of K ₂ O and Na ₂ O
90 parts by weight of kaolin, which is 2.0% by weight, 56.0% by weight of SiO ₂ , 39.0% by weight of Al ₂ O _3, and the total amount of K ₂ O and Na ₂ O.
5 parts by weight of Kibushi clay, which is 1.2% by weight, was mixed. 60% by weight of this mixture and 40 parts by weight of water were mixed to prepare a slurry, which was treated with a planetary mill for 20 minutes. The obtained slurry was used as a base layer coating liquid. This coating solution was sprayed onto the surface of the plate-shaped ceramic body by using a spray gun, and air-dried. Then, a slurry of zircon glaze containing 2% by weight of an inorganic antibacterial agent having a silver content of 25% by weight was glazed on the dried underlayer. This was fired according to a firing program in which the temperature was kept at 1200 ° C for 2 hours to obtain an antibacterial pottery. The thickness of the base layer after firing was 150 μm, and the thickness of the glaze layer was 250 μm.

[0016]Example 3 To prepare the surface treatment composition according to the invention, SiO 2₂But
98.6% by weight, Al₂O₃0.6% by weight, K₂O and Na₂With O
65 parts by weight of silica stone weighing 0.3% by weight and SiO ₂Is 45.8
Wt%, Al₂O₃Is 38.4% by weight, K₂O and Na₂Total with O
32 parts by weight of kaolin whose amount is 2.7% by weight, and SiO₂Is 66.
7% by weight, Al₂O₃Is 18.6% by weight, K₂O and Na₂Total with O
3 parts by weight of feldspar in an amount of 13.9% by weight were mixed. this
The resulting mixture was mixed with 60 parts by weight of water and 40 parts by weight of water.
The rally was processed on a planetary mill for 20 minutes. The obtained slurry
Was used as the coating liquid. Apply this coating liquid to a plate-shaped ceramic substrate
A spray gun was used for spray application and drying. Under this
Distribute 2% by weight of inorganic antibacterial agent with 25% by weight of silver on the formation
The combined zircon glaze slurry was glazed and dried. this
According to a firing program that holds the temperature at 1200 ° C for 2 hours.
Then, it was fired to obtain an antibacterial pottery. Thickness of base layer after firing
Is 60 μm and the thickness of the glaze layer is 250 μm
It was

Example 4 SiO ₂ was used to prepare a primer composition according to the invention.
8.6% by weight, 0.6% by weight of Al ₂ O _3, 25 parts by weight of silica stone having a total amount of K ₂ O and Na ₂ O of 0.3% by weight, 79.9% by weight of SiO ₂ and 13.9% by weight of Al ₂ O _3. %, 65 parts by weight of Amakusa stone powder whose total amount of K ₂ O and Na ₂ O is 2.8% by weight, 77.2% by weight of SiO ₂ , 17.2% by weight of Al ₂ O ₃ , K ₂ O and Na ₂ O Was mixed with 10 parts by weight of petalite whose total amount was 0.6% by weight.
To 60 parts by weight of this mixture, 40 parts by weight of water was added and treated with a planetary mill for 20 minutes to prepare a slurry. This slurry was used as a base layer coating liquid. This coating solution was sprayed onto a plate-shaped ceramic base using a spray gun and dried. An inorganic antibacterial agent with a silver content of 25% by weight is applied to this underlayer 2
A slurry of zircon glaze containing 1% by weight was applied and dried. This was fired according to a firing program in which the temperature was kept at 1200 ° C for 2 hours to obtain an antibacterial pottery. The thickness of the base layer after firing is 150 μm, and the thickness of the glaze layer is 250 μm
Met.

Comparative Example 1 An antibacterial pottery was produced in the same manner as in Example 1. However, 2% of an inorganic antibacterial agent with a silver content of 25% is directly applied to the surface of the plate-shaped ceramic base without forming an underlayer of the base treatment composition.
A slurry of zircon glaze containing the above was applied and dried. This was fired according to a firing program in which the temperature was kept at 1200 ° C for 2 hours to obtain an antibacterial pottery. The thickness of the glaze layer after firing was 250 μm.

Example 5 In the same manner as in Example 1, the plate-shaped ceramic base material was sprayed with a coating liquid containing the undercoating composition using a spray gun and dried,
Thereafter, a slurry of zircon glaze containing 2% by weight of an inorganic antibacterial agent having a silver content of 25% by weight was applied onto the undercoat layer, and the slurry was dried and dried. This was fired according to a firing program in which the temperature was kept at 1200 ° C for 2 hours to obtain an antibacterial pottery. The thickness of the base layer after firing is 20 μm, and the thickness of the glaze layer is 250
was μm.

Example 6 In the same manner as in Example 2, the coating solution containing the base treatment composition was spray-coated on a plate-shaped ceramic body using a spray gun and dried. Thereafter, a slurry of zircon glaze containing 2% by weight of an inorganic antibacterial agent having a silver content of 25% by weight was applied onto the underlayer, and the slurry was glazed and dried. This was fired according to a firing program of holding it at a temperature of 1200 ° C for 2 hours to obtain an antibacterial pottery. The thickness of the base layer after firing is 20 μm, and the thickness of the glaze layer is 250
was μm.

Comparative Example 2 40 parts by weight of water was added to 60 parts by weight of silica containing 98.6% of SiO ₂ , 0.6% of Al ₂ O ₃ and 0.3% of the total amount of K ₂ O and Na ₂ O. After processing for 20 minutes with a planetary mill, the resulting water slurry was used as a coating liquid for the underlayer. This coating solution was sprayed onto the plate-shaped ceramic base material by using a spray gun in the same manner as in Example 1. A slurry of zircon glaze in which 2% by weight of an inorganic antibacterial agent having a silver content of 25% by weight was mixed on the undercoat layer was glazed and dried in the same manner as in Example 1. This was fired according to a firing program in which the temperature was kept at 1200 ° C for 2 hours to obtain an antibacterial pottery. The thickness of the base layer after firing was 150 μm, and the thickness of the glaze layer was 250 μm.

[0022]Comparative Example 3 SiO₂Is 98.6% by weight, Al₂O₃0.6% by weight, K₂O and Na₂O
And 19 parts by weight of silica stone whose total amount is 0.3% by weight, and SiO₂Is 4
5.8% by weight, Al₂O₃Is 38.4% by weight, K₂O and Na ₂With O
7 parts by weight of kaolin weighing 2.7% by weight and SiO₂Is 6
6.7% by weight, Al ₂O₃Is 18.6% by weight, K₂O and Na₂With O
57 parts by weight of feldspar, which weighs 13.9% by weight, and SiO₂Is 65.6
Amount%, Al₂O₃Is 0.4% by weight and MgO is 32.9% by weight.
17 parts by weight of Luk was mixed to prepare an underlayer composition.
To 60% by weight of this composition, 40% by weight of water was added to
Slurry for 20 minutes to prepare a slurry. Example 1
Similarly, using this slurry as a coating liquid,
It was applied and dried using a spray gun. After this,
On the obtained underlayer, a silver content of 25 was obtained in the same manner as in Example 1.
Zircon glaze mixed with 2% by weight of inorganic antibacterial agent
The slurry was glazed and dried. This is a temperature of 1200 ℃ at 2 o'clock
Fired according to the firing program held for a while, antibacterial pottery
Got The thickness of the base layer after firing is 150 μm,
The thickness of the drug layer was 250 μm.

Table 1 shows the compositions of the base treatment compositions of Examples 1 to 6 and Comparative Examples 2 and 3. In addition, the antibacterial properties (Escherichia coli, Staphylococcus aureus) of the antibacterial pottery obtained in Examples 1 to 6 and Comparative Examples 1 to 3 were tested in accordance with JIS Z2801 "Antibacterial processed product-Antibacterial test method / antibacterial effect". did. As a result, those having an antibacterial activity value of 2 or more were judged to have antibacterial properties. The results are shown in Tables 2 and 3.

The specific intensity of silver on the surface of the glaze layer of the antibacterial pottery obtained in Examples 1 to 6 and Comparative Examples 1 and 3 was measured using an analytical electron microscope (EPMA). The results are shown in Table 4.
Shown in.

[0025]

[Table 1]

[0026]

[Table 2]

[0027]

[Table 3]

[0028]

[Table 4]

Further, the silver content in the glazes of the antibacterial ceramics obtained in Examples 1 and 3 and Comparative Examples 1 and 3 was 10 from the surface.
The distribution state of silver in the depth direction was examined by fluorescent X-ray analysis every time polishing was performed up to a depth of 00 μm and 50 μm. EPM
The measurement conditions of A are acceleration voltage 15 kV, irradiation current 5.00
× 10 ^-8 A, irradiation beam diameter 10 μm, measurement wavelength 0.41
It was 5562 nm (4.15552Å). The results are shown in FIG. 2 (Example 1), FIG. 3 (Example 3), FIG. 4 (Comparative Example 1), and FIG. 5 (Comparative Example 3).

As is clear from Tables 2 and 3, the antibacterial pottery of Examples 1 to 6 had an antibacterial activity value of 2 or more against Escherichia coli and Staphylococcus aureus and showed good antibacterial properties. The antibacterial pottery of Examples 1 to 4 showed extremely excellent antibacterial activity with an antibacterial activity value of more than 6. However, the antibacterial pottery of Comparative Examples 1 and 3 had an antibacterial activity value of less than 2 and did not show sufficient antibacterial properties. In Comparative Example 2, peeling occurred between the surface-treated surface and the ceramic body, and the test could not be performed.

Table 4 shows Examples 1 to 6 and Comparative Examples 1 and 3.
The silver intensity of the glaze surface of the antibacterial pottery obtained in 1. was measured by an analytical electron microscope (EPMA). Although the glaze used contained the same amount (2%) of the silver-based inorganic antibacterial agent, it showed different strengths. Although Examples 1 to 6 showed high silver strength, Comparative Example 1 had a silver strength of about 50% of Examples 1 to 4, and Comparative Example 3 showed only 40% of the silver strength. In the antibacterial pottery of Comparative Example 2, peeling occurred between the surface-treated surface and the substrate, and the test was impossible.

2 to 5 show the silver concentration distribution in the depth direction in the glaze layer. In the antibacterial pottery of Examples 1 and 3 (FIGS. 2 and 3), it was confirmed that the diffusion of silver was stopped in the range of the underlayer. On the other hand, in Comparative Example 1 (FIG. 4), since there was no underlayer, it was confirmed that silver diffused directly from the glaze layer to the substrate. In Comparative Example 3 (FIG. 5), since the underlayer was completely melted and integrated with the glaze layer, the silver in the antibacterial agent was distributed over the entire glaze layer and underlayer integrated with the underlayer, and The diffusion of silver was reaching the body.

[0033]

The base treatment composition of the present invention is formed between the base of an antibacterial glaze layer having an antibacterial glaze layer and the antibacterial glaze layer, and an antibacterial agent (for example, silver or a silver compound) is applied from the glaze layer to the base. It is useful for preventing it from diffusing into the inside and reducing its antibacterial effect. By providing such an underlayer, the antibacterial article of the present invention and the method for producing the same are effective antibacterial. It has excellent properties and is cost-effective and excellent.

[Brief description of drawings]

FIG. 1 is a side cross-sectional explanatory view showing the structure of an antibacterial article of the present invention.

FIG. 2 is a silver distribution diagram of an example (Example 1) of the antibacterial article of the present invention.

FIG. 3 is a silver distribution chart of another example (Example 3) of the antibacterial article of the present invention.

FIG. 4 is a silver distribution chart of an example (Comparative Example 1) of an antibacterial article other than the present invention.

FIG. 5 is a silver distribution chart of still another example (Comparative Example 3) of the antibacterial article outside the present invention.

[Explanation of symbols]

1 ... Base of antibacterial article (base) 2 ... Underlayer 3. Glaze layer containing antibacterial agent

Claims (6)

[Claims] 1. It is characterized by containing 75 to 90% by weight of SiO ₂ , 10 to 20% by weight of Al ₂ O ₃ , and 0.1 to 3% by weight in total of K ₂ O and Na ₂ O. Antibacterial glaze base treatment composition. 2. A base layer containing the antibacterial glaze base treatment composition according to claim 1 formed on the surface of a substrate, and a glaze layer containing an antibacterial agent formed on the base layer. An antibacterial article characterized by: 3. The antibacterial article according to claim 2, wherein the antibacterial agent contains silver or a silver compound. 4. The antibacterial article according to claim 2, wherein the base layer containing the antibacterial glaze base treatment composition has a thickness of 10 to 500 μm. 5. An undercoat layer is formed by applying a slurry containing the antibacterial ceramic pretreatment composition according to claim 1 to the surface of a base material, and a glaze containing an antibacterial agent is applied onto the undercoat layer, A method for producing an antibacterial article, which comprises firing to form a glaze layer. 6. The method for producing an antibacterial article according to claim 5, wherein the antibacterial agent contains silver or a silver compound.