JP3001018B2 - Enamel products with metallic luster and their production - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to relates to enameled product and its manufacturing method having the gloss of the metallic.

[0002]

2. Description of the Related Art Enamel products are widely used in various panels and household goods due to the corrosion resistance and cleanliness of the enamel layer covering the surface of the metal substrate, but most of them mask the undesired coloring due to the lower glaze. For this purpose, an opalescent agent such as zirconium oxide or titanium oxide is added to the upper glaze to make it milky white. However, since pure milky white is monotonous and lacks aesthetics, color glaze is further applied on the upper glaze layer, but ordinary color glaze using only metal oxide as a pigment is beautiful and uniform It was difficult to obtain a glossy surface.

[0003]

SUMMARY OF THE INVENTION The present invention is intended to solve the difficulties of the conventional color glaze as described above, and to easily provide an enamel product having a beautiful uniform metallic luster. It was done.

[0004]

The enamel product having a metallic luster according to the present invention is an enamel product having at least a lower glaze layer and an upper glaze layer provided on a metal substrate, and an oxidized product in the upper glaze layer. includes a mica powder having a surface coated with titanium or iron oxide, and contains fluorine in the upper glaze, is characterized in that it has at most 1% content of it. In addition, the method for producing an enamel product having a metallic luster according to the present invention comprises forming a lower glaze layer on a metal substrate, and then including fluorine on the lower glaze layer ,
The content is at most 1%, and a small amount of mica powder coated on the surface with titanium oxide or iron oxide is added.

In the present invention, first, an underglaze layer is formed on a metal substrate. The glaze used for the underglaze may be a conventionally used glaze, and a conventional underglaze frit and a mill additive are added together with water. It was ground with a ball mill to form a lower glaze slurry, which was dried on a surface of a cleaned metal substrate by a conventional method.
The lower glaze layer is formed by firing at about 0 ° C. Next, an upper glaze slurry is applied on the lower glaze layer, and the upper glaze slurry is obtained by pulverizing an upper glaze frit and a mill additive together with water with a ball mill by a conventional method. In the case of the above, the top glaze slurry contains fluorine in its composition , and its content is at most 1%, and about 1 to 15% by weight of the mica powder coated with titanium oxide or iron oxide. A small amount is added, this is applied to the lower glaze layer by a conventional method, dried, and fired at about 780 to 800 ° C. to form an upper glaze layer.

[0006] The enamel product thus obtained is excellent in corrosion resistance by the lower glaze layer fused to the metal base and the upper glaze layer fused to the same as the conventional enamel product. The glaze layer is formed by firing the upper glaze slurry to which a small amount of mica powder coated with titanium oxide or iron oxide is added, with the fluorine content of the frit or mill additive being up to 1%. Mica powder whose surface is coated with titanium oxide or iron oxide has a beautiful uniform uniform surface with a metallic luster based on the strong birefringence of the mica powder and the hue of the titanium oxide or iron oxide. It has a metallic luster. The reason why the fluorine content of the upper glaze slurry is set to at most 1% is that if it exceeds 1%, the desired beautiful and uniform metallic luster is obtained by firing at about 800 ° C., which is a normal firing temperature. The fact that the product did not become an enameled product was confirmed by the results of numerous experiments.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS 100 parts of a conventional underglaze frit, 7 parts of clay of a mill additive, 5 parts of silica, 0.5 parts of hydrated borax, and 0.3 parts of sodium nitrite were ground together with 50 parts of water in a ball mill and ground glaze slurry. Was sprayed on both the front and back surfaces of a 100 mm × 100 mm × 1.6 mm cleaned iron plate, dried and fired at 810 ° C. for 4 minutes to form a lower glaze layer. Next, 100 parts of the upper glaze frit having the composition shown in Table 1 and 3 parts of clay of the mill additive,
0.4 parts of bentonite, 0.2 parts of magnesium carbonate, 0.25 parts of potassium chloride, and 0.25 parts of potassium silicofluoride were added with 40 parts of water, and the pulverized mud was made to have a fluorine content of 1% or less. Then, 1 to 15% by weight of mica powder whose surface was coated with titanium oxide was added thereto, and the upper glaze slurry was sprayed on the lower glaze layer, and dried and fired at 790 ° C. for 3 minutes. The enamel product obtained here had a metallic luster reminiscent of beautiful silver as shown in Table 1 as "Appearance" of the product appearance. On the other hand, in the case of the upper glaze having a fluorine content of more than 1%, the product appearance did not become a beautiful gloss as shown in Comparative Examples in Table 1 as "impossible".

[Table 1]

[0008]

As apparent from the above description, the present invention provides a top glaze slurry for forming a top glaze layer with a fluorine content of 1% to 0% (excluding 0%) of titanium oxide or oxide. By adding a small amount of mica powder whose surface is coated with iron, it is possible to easily provide enamel products with a beautiful and uniform metallic luster, and to open up a new field for conventional enamel products. It is of great industrial value.

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Claims (2)

(57) [Claims] 1. An enamel product comprising at least a lower glaze layer and an upper glaze layer provided on a metal base, wherein the upper glaze layer contains mica powder coated with titanium oxide or iron oxide, and the upper glaze includes fluorine into the layer, enamel products with gloss metallic, characterized in that it has at most 1% content of it. 2. A method of forming a lower glaze layer on a metal substrate and then forming a small amount of mica powder containing fluorine on the lower glaze layer , the content of which is at most 1%, the surface of which is coated with titanium oxide or iron oxide. A method for producing an enamel product having a metallic luster, characterized in that the product is coated with an upper glaze slurry to which is added and dried and then fired.