JPH0124752B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to a glazed product in which a glaze layer is provided on a molded body of ceramics, metal, cement, etc., and in particular, a crack pattern is provided on the surface side of the glaze layer that prevents rainwater from penetrating. Concerning what caused this to appear. [Prior art and problems to be solved] Conventionally, to obtain a matte glazed product, a compound that precipitates crystals is added to the normal glaze raw material, and the glaze is mixed uniformly throughout the product. The slurry-like glaze was adjusted. Then, by applying this onto a molded object of ceramics, metal, cement, etc. and firing it, a mat-like glazed product with a crystalline glazed surface is obtained. However, in the glaze layer of such a glazed product, as mentioned above, the above compound is uniformly distributed throughout the glaze layer, so the thermal expansion coefficient and firing temperature of the glaze are controlled by the compound. Significant changes occur. For this reason, the coefficient of thermal expansion and the firing temperature were sometimes significantly different from those of molded bodies such as ceramics, metals, and cement. As a result, the glaze may not melt properly, resulting in poor compatibility with the molded object, or open cracks 2 may appear in the glaze layer 1 as shown in FIG.
Occasionally, there was a When open cracks 2 occur in the glaze layer in this way, rainwater or the like penetrates into the molded body 3 of ceramics or the like through the open cracks 2, and when this freezes, the molded body 3 itself may be destroyed. Additionally, if there is a change in the coefficient of thermal expansion or firing temperature of the glaze, the glaze cannot be fired unless the temperature at which the molded body starts to change thermally changes, and the properties of the molded body itself may be transformed or destroyed during firing. Ta. The present applicant invented a glazed product to eliminate the above-mentioned drawbacks of the prior art, and filed a patent application for this product in Japanese Patent Application No. 58-51111.
The application has already been filed as a No. The gist of the invention related to the existing application is that in a glazed product in which a glaze layer is provided on a molded body of ceramics, metal, cement, etc., from the surface of the glaze layer to the interface with the molded body, titanium oxide, zirconium oxide, oxidized It is made by distributing oxidized compounds such as strontium and tin oxide that have excellent chemical resistance and durability, and the distribution density of the oxidized compounds is dense on the surface side of the glaze layer and coarse on the interface side with the molded object. It is characterized by continuously changing. By the way, in the process of inventing the above-mentioned patent application, the inventors found that when the distribution of the oxide compound in the glaze layer did not show a continuous change, that is, the oxide compound gradually formed a thick layer. When a relatively prominent boundary is observed between the oxide compound layer and the glaze layer, the oxide compounds aggregate in various fine and coarse sections, causing cracks on the surface of the oxide compound layer. We discovered the phenomenon that occurs. As already mentioned, cracking phenomena such as those described above have heretofore been considered undesirable. However, the inventors broke down the preconceived notions regarding the above-mentioned cracking phenomenon and thought about ways to put it to good use. In other words, it is an object of the present invention to convert the cracking phenomenon, which has heretofore been given a negative evaluation, to a positive evaluation. [Means for Solving the Problems] The means of the present invention adopted to solve the above problems is that in a glazed product in which a glaze layer is provided on a molded body of ceramics, metal, cement, etc., a zirconium compound is provided on the glaze layer. , a surface treatment liquid layer made of one or more types of titanium compounds etc. is provided, and a pattern due to directional or non-directional cracks appears on the surface treatment liquid layer, and the cracks are formed by glaze. It's where it's being filled. [Operation] According to the above solution, since only the glaze component is in direct contact with the molded object such as ceramics, metal, cement, etc., the molded object will There is no difference in the coefficient of thermal expansion between the glaze layer and the glaze layer. Also,
Since the cracks appearing in the surface treatment liquid layer are filled with the glaze, there is no risk of rainwater or the like penetrating into the molded article, which would have an adverse effect on the molded article. Moreover, the pattern created by the cracks creates a kind of taste and improves the commercial value of the molded article. [Example] The structure of the present invention will be described below based on an example shown in the drawings. Figures 2 and 3 show glazed products 4 according to the present invention.
This figure shows a cross-sectional state during the manufacturing process. The basic method for manufacturing the glazed product 4 is to first apply a glaze 6 onto a molded body 5 of ceramics, metal, cement, etc. to form a glaze layer 7. This glaze layer 7 may be in a raw state, or it may be fired once to a glassy state. In the case of a raw glaze layer,
After applying the glaze 6, it is dried and cured at room temperature.
When firing once, after applying the glaze 6, it is dried and cured at room temperature, fired in a firing furnace, and then cooled to room temperature. After forming the glaze layer 7, a surface treatment liquid 8 containing components such as a zirconium compound and a titanium compound is applied to the surface to form a surface treatment liquid layer 9.
will be established. This surface treatment liquid 8 may be one in which the components are oxidized by firing and the oxidized compounds are aggregated. Further, the surface treatment liquid 8 may be a mixture of two or more of the above compounds. Specific examples of the surface treatment liquid 8 include an aqueous dispersion of zirconium oxide or zirconium hydroxide, an aqueous dispersion of titanium oxide or titanium hydroxide, and an aqueous dispersion of zirconium oxide or hydroxide.
Examples include an ethyl alcohol solution of n-propoxide and an ethyl alcohol solution of titanium iso-propoxide. The selection of the surface treatment liquid 8 and the amount of application thereof are such that the surface layer state expected in the production of the glazed product 4 is achieved, that is, there is a relatively prominent boundary between the formed surface treatment liquid layer 9 and the glaze layer 7. It is determined by taking into account that cracks are recognized and cracks appear on the surface of the surface treatment liquid layer 9. After applying the surface treatment liquid 8, firing is performed near the softening point of the glaze 6. By this firing, the components of the surface treatment liquid 8 soften the glaze 6, slightly penetrate into the glaze 6, and react with the glaze 6. The above reaction between the components of the surface treatment liquid 8 and the glaze 6 is performed before the fluidity of the glaze 6 becomes significantly large. The compounds generated by the oxidation of the components of the surface treatment liquid 8 gather in large numbers near the upper layer of the glaze layer 7 and increase its thickness, eventually forming the surface treatment liquid layer 9. Become. In this case, the surface treatment liquid layer 9 is
Even if the reactant is slightly dispersed in the glaze layer 7, a relatively distinct boundary between the reactant and the glaze layer 7 is formed. In such a state, the surface treatment liquid layer 9
The oxidized compounds forming the agglomerated particles aggregate into various fine and coarse sections, and cracks occur in adjacent areas of the agglomerated sections. Therefore, a crack pattern appears on the surface of the surface treatment liquid layer 9. Note that the components of the surface treatment liquid 8 are present as oxide crystals on the surface of the surface treatment liquid layer 9, and therefore the surface treatment liquid layer 9 exhibits a mat shape as well as a crack pattern. FIG. 4 schematically shows the cross section of the glazed product 4 completed as described above. A crack 10 exists in the surface treatment liquid layer 9, and this crack 10 is similar to the glaze layer 1 in the case described above with reference to FIG.
This is completely different from the open crack 2 that occurs in . This is because the crack 10 in FIG. 4 is filled with the glaze 6 and is in a closed state. The mechanism by which the cracks 10 are filled with the glaze 6 will be explained as follows. In other words, since the components of the surface treatment liquid 8 are composed of substances with high refractory properties, they will not melt by themselves or completely react with the glaze 6 during firing at temperatures of about 800 to 1300°C, and will not react with the glaze 6 during the firing process. Inside, the aforementioned components gather near the surface, increasing in thickness and forming a layer. There is a core within the layer, around which many components aggregate. A void is generated between adjacent aggregated component groups, and this void is a crack 10. On the other hand, the glaze 6 thermally expands in the low temperature range of the firing temperature, and becomes highly fluid in the high temperature range. The glaze 6 with increased fluidity flows into the voids (crack 10) between the aggregated component groups. In this way, the crack 10 is filled with the glaze 6 and becomes closed. Therefore, in the case of the crack 10, unlike the case of the conventional open crack 2, the skin of the molded body 5 is not exposed, and it is completely impossible for rainwater etc. to penetrate. Moreover, the adhesion between the glaze layer 7 and the surface treatment liquid layer 9 is extremely good, and the surface treatment liquid layer 9 is not physically or chemically deteriorated. As shown in FIG. 4, although some penetration of reactants originating from the surface treatment liquid 8 into the glaze layer 7 is observed, the degree of penetration is very small and causes a change in the properties of the glaze layer 7 itself. It's not a thing. Of course, what is in direct contact with the molded body 5 is
This is a vitrified glaze 6. The thermal expansion coefficient of the glaze 6 in this part is similar to that of the molded body 5, and the raw materials for the glaze 6 and their mixing ratios are selected and set according to the material of the molded body 5. Needless to say. Therefore, the problem of separate cracks occurring in the glazed product 4 due to the difference in thermal expansion coefficient between the glaze layer 7 and the molded body 5 is eliminated. Next, an example of specifically manufacturing the glazed product 4 will be described. As already mentioned, the application of the surface treatment liquid that forms the basis of the surface treatment liquid layer requires the following steps:
There are cases where it is applied on the raw glaze layer and cases where it is applied on the glaze layer after firing. The former case will be mainly described below with reference to Tables 1 and 2. As the molded body 5, a 109 mm square interior unglazed tile was used. A predetermined number of these unglazed tiles are prepared, and a ceramic glaze having the composition shown in Table 1 is applied to the surface of the unglazed tiles by a wet curtaining method or the like. This is then dried and cured at room temperature.

[Table] After drying and curing as described above, a 20Wt5% aqueous dispersion of titanium oxide was spray applied to the surface of the glaze layer as a surface treatment liquid to form a surface treatment liquid layer. The amount of surface treatment liquid applied at that time was varied in various ways. It is shown in Table-2. In the same table, trial number 1 is a comparative example product, and trial numbers 2 to 4 are example products according to the present invention.

〔Effect of the invention〕

As explained above, the glazed product according to the present invention is one in which a surface treatment liquid made of one or more of zirconium compounds, titanium compounds, etc. is provided on the glaze layer provided on the molded body, A pattern of directional or non-directional cracks appears on the surface of the surface treatment liquid layer, and the cracks are filled with the glaze and are in a closed state. Therefore, the present invention has the following effects. What is directly adhered to the molded body is the glaze layer, which has a small difference in coefficient of thermal expansion between the molded body and the molded body. It shows extremely good adhesion due to its affinity to the extent that it slightly penetrates into the glaze layer.
There is no risk of any harmful physical or chemical deterioration even when used for many years in an environment of repeated heating and cooling, and high-quality glazed products can be provided. Each crack in the crack pattern that appears on the surface of the surface treatment liquid layer is filled and closed with glaze, so it is completely different from the open cracks that occur in conventional glazed products, and it is difficult for rainwater to penetrate. Therefore, the molded product does not deteriorate. The crack pattern on the surface of the surface treatment liquid layer creates an elegant tone due to the luster of the glaze that fills and closes each crack and the matte pine shape, improving the commercial value of the glazed product.

[Brief explanation of drawings]

FIG. 1 is a schematic vertical cross-sectional view showing a conventional glazed product, FIGS. 2 and 3 are schematic vertical cross-sectional views showing the state of the glazed product according to the present invention during the manufacturing process, and FIG. Fig. 5 is a schematic vertical cross-sectional view showing the finished state of the glazed product according to the present invention, and Fig. 5 is a plan view showing the surface condition of the glazed product, and Fig. Figures B, C and D are examples of the present invention in which a non-directional crack pattern appears, and Figures A, B, C and D are planes showing the surface condition of the glazed product according to the present invention. This figure shows a geometric directional crack pattern. 4... Glazed product, 5... Molded object, 7... Glaze layer, 9... Surface treatment liquid layer, 10... Cracks.

Claims (1)

[Claims] 1. In glazed products in which a glaze layer is provided on a molded body of ceramics, metal, cement, etc., a surface treatment liquid layer consisting of one or more types of zirconium compounds, titanium compounds, etc. is provided on the glaze layer, and the surface A glazed product characterized in that a pattern of directional or non-directional cracks appears in the treatment liquid layer, and the cracks are filled with glaze.