JPS63262479A - Enameled product having metallic tone and finely spotted pattern - Google Patents

Abstract

PURPOSE:To produce a high quality enameled product having a metallic tone and a finely spotted pattern at a low cost by baking glaze for enameling contg. a specified amt. of a metallic nitrate in the form of fine spots on a glossy enamel formed on a substrate. CONSTITUTION:A glossy enamel layer 1 is formed on a substrate of iron, aluminum, stainless steel copper or the like to be enameled. Glaze for enameling prepd. by adding 0.05-2pts.wt. nitrate of Fe, Ni, Co, Cu or Mn to 100pts.wt. frit forming an emulsion crystallized mat substance at high temp. is sprinkled on the enamel layer 1 by spraying or other method and baked at about 700-850 deg.C to form a finely spotted enamel layer 2 made of the baked body of the glaze. Thus, an enameled product 3 having a finely spotted pattern and a metallic tone is obtd. without deteriorating the characteristics of the enamel layer 1. The pattern has the color of the metal used in the glaze.

Description

[Detailed description of the invention] (Industrial application field) This invention relates to enamel products.

(Prior technology) Enamel products, which are generally made by coating the surface of various metal substrates such as iron, aluminum, stainless steel, and copper with an enamel layer, are used for various household items such as interior and exterior panels of buildings, containers, cooking utensils, and decorative items. Although it is widely used in products and other products, the unpatterned enamel layer has a monotonous appearance, so demand for patterned enamel layers is increasing. Among these patterned enamel layers, an enamel layer that has a small speckled pattern with a metallic luster and has an appearance like a metallic paint (hereinafter referred to as metallic tone in the present invention) has an excellent appearance and is preferable. Several methods have been tried for formation, but there are many problems.

In other words, this method of forming a metallic enamel layer is as follows:
Commercially available expensive pearlescent pigments whose main ingredient is mica,
The mainstream method is to add a milled transparent glaze or a semi-emulsified enamel glaze to the enamel glaze and then use this as a top glaze and fire the glaze, but the pattern is very fine and if you don't look closely, it will look metallic. I don't know what the tone is. Additionally, due to the use of spray and surface smoothness, it is not possible to use pigments with large pigment particles, and the firing temperature must be lower than 800°C, otherwise the pattern tends to disappear. In the case of enamel, it is often necessary to mix and use a special glaze that can be used at low temperatures. There is also a cloisonné enamel technique that uses gold, silver, copper, etc. powders or pieces of foil, but these are extremely expensive. Furthermore, there is a technology that sprays metals such as aluminum and stainless steel onto the enamel layer.
Not only is the work time-consuming and equipment costs are high, but the adhesion of metal grains to the enamel layer is poor, and the heat of sprayed metal! There are problems such as a decrease in weather resistance due to cracks in the enamel layer and corrosion of metal grains due to i9, and a decrease in stain resistance due to damage to the rough surface of the surface. Furthermore, even if metal powder such as aluminum or stainless steel is added to the glaze, unlike painting, the metal powder will oxidize or dissolve during firing of the glaze, and a metallic enamel layer will not be formed.

(Problems to be Solved by the Invention) This invention solves the above-mentioned conventional problems by using inexpensive raw materials and improving the characteristics of the enamel layer such as smoothness, chemical resistance, stain resistance, and adhesion. The object of the present invention is to provide a metallic-like enamel product having small speckled patterns exhibiting various metallic colors such as copper-like, golden-like, pure copper-like, and so-called aluminum (or lead) without impairing the quality of the product.

(Means for solving the problem) However, the enamel product of the present invention has a glossy enamel layer provided on the enamel substrate, and on this enamel layer,
Fe, Ni, and Co for the Fribut 100 heavy hanging part for forming a matte enamel layer.

CLJ, 0.05 nitrate of one metal among Mn
This is an enamel product with a metallic pattern of small speckles, which is characterized by having a small speckled enamel layer made of a fired body of enamel glaze with double roof addition.

The enamel substrate in this invention includes iron, aluminum,
Various metal plates such as stainless steel and copper can be used.

In this invention, the enamel layer provided on the enamel substrate is a glossy one, but this is to make the coloring of the matte small speckled enamel layer provided thereon stand out. If so, its color and surface smoothness do not matter.

In addition, as a frit for forming a matte enamel layer with small spots on the glossy enamel layer, when the enamel substrate is made of iron, copper, or stainless steel, the metal oxide composition (wt%) is SiO2 and Tic) + and Zr
Add 40 to 65% of total O+ and 20% to Na2O. L 1
20 (D, two or more containing at least Li2O are 10
~25%, ZnO, MC) 4 to 26% of at least two or more types containing BaO and ZnO among O, Bad, and CaO,
B203, A 1,203.8b203, containing 5 to 20% of at least one type containing at least B2O3, and 1 to 6.5% of the total of P20S and MOO3 as other components, and S i 02 /T i 02 value is 6
A frit that forms a high-temperature emulsion crystallized matte in the range of 5/35 to 40/60 is suitable, and this frit becomes matte (disappears) at a firing temperature of 700 to 850°C, It has good fluidity and can easily form a small dot-shaped enamel layer with a thickness of 10 mm or less. In addition, when aluminum or aluminized steel plate is used as the substrate, either leaded or lead-free frit can be used.As a frit for forming a spotted matte enamel layer, it has low fluidity due to the low firing temperature. Although it is difficult to obtain a good crystallized matte enamel layer, the usual firing temperature (500-600
Either use a frit that semi-melts at 0°C to form an emulsified matte enamel layer, or add high melting point materials such as titanate, titanium oxide, Al2O3 to ordinary glossy enamel raw materials to create a matte layer. The frit composition of the former is 15 to 45% of the total of 5iC)+ and TiO+ or ZrO2, 25 to 35% of the total of Na2O, 20 and Li2O, and B203 and 5b20.
3 and Al2O3 in total from 5 to 15%, and PbO and ZnO or other components to 10 to 30% (for lead-free systems, pbo=
o%) is preferred.

In this invention, the small speckled enamel layer is formed from a matte enamel layer because the metal nitrate produces a good metallic color, and because it contrasts with the gloss of the glossy enamel layer forming the base surface. This is to make the speckled pattern part stand out and to obtain a metallic appearance as a whole. The small speckled enamel layer may be formed by baking a glossy enamel layer on the substrate, applying glaze by spraying, etc., and then firing it, or The glaze may be formed by spraying or the like on the wet surface of the coating after the water film has disappeared, and then firing it together with the glossy enamel layer.

In this invention, the amount of metal nitrate added to the frit for forming a pine enamel layer is 0.05 to 2%. If the addition R is less than 0.05%, the metal color becomes pale and small spots are formed. This is because the pattern becomes unclear, and if the amount added exceeds 2%, the amount of gasified nitric acid increases and the appearance of small spots becomes poor due to foaming.

(Function) In the enamel product of this invention, when firing the small speckled glaze layer containing metal nitrates, the metal nitrates are thermally decomposed, nitric acid gas is separated, metals are reduced and precipitated, and the metal content is reduced to F.
A small speckled matte enamel layer with an e-like copper tone, a golden tone with Ni, a brass tone with Co, a pure copper tone with Cu, and an aluminum or copper tone with Mn. is formed, and a low-gloss small speckled pattern of the various metal colors described above appears on the glossy surface of the glossy enamel layer forming the ground color, resulting in an enamel product having a metallic appearance. The glossy enamel layer and the dotted enamel layer thereon are both glassy layers and have poor adhesion to each other, forming a smooth and strong enamel coating layer on the enamel substrate.

(Example) Examples and comparative examples of the present invention will be described below.

First, the enamel substrates were an enameled steel plate with a thickness of 1.6#11, a 5US-430 stainless steel plate with a thickness of 11M1, an aluminized steel plate with a thickness of 0.5 m, and a 1#III thick plate.
The enamel steel plates were pre-treated with alkaline degreasing, pickling, Ni dip, and neutralization, and the stainless steel plates were roughened by sandblasting. The aluminum plated steel plate was degreased with a special alkaline degreasing solution, and the copper plate was treated with a 5% nitric acid solution.

Next, as the frit for enamel, one having the composition shown in Table 1 and melted in a crucible for 1 KFI at 250° C. for 60 minutes was used. Using this frit, 15 types of glazes A to Ell for iron enamel shown in Table 2 and 8 types of glazes 01 to D8 for aluminum enamel shown in Table 3 were prepared. The base glaze in the table is a glaze for forming a glossy enamel layer on an enamel substrate.
Spotted glaze is a glaze that forms a matte enamel layer with small spots on top of this glossy enamel layer.

When the above-mentioned enamel substrate and glaze were used and the glazes were applied and fired in the dimensional combinations shown in Table 4, enamel products having the spotted coloring shown in the table were obtained. The contents will be explained below.

[Example 1] Spray glaze A on both sides of an enameled steel plate and heat to 840°C.
After firing for 5 minutes, apply 81 base glaze on one side.
On top of the glossy enamel layer fired at 0°C for 5 minutes, E1
Spray the spotted glaze into small spots and heat at 800℃ for 5 minutes.
Bake for a minute. As a result, as shown in FIG. 1, an enamel product 3 with a metallic appearance is obtained, in which a large number of small speckled matte enamel layers 2 exhibiting a brass color are scattered on a glossy enamel layer 1 exhibiting a white color. I was able to get it.

[Example 2] When the same treatment as in Example 1 was carried out using a stainless steel plate, an enameled product with the same spotted coloration as in Example 1 was obtained.

[Examples 3 to 7] Using an enameled steel plate, E2 to E6 instead of E1 spotted glaze
When the glaze was applied and fired under the same conditions as in Example 1 except that a spotted glaze was used, metallic-like enamel products with various spotted colors shown in Table 4 were obtained depending on the type of metal component of the metal nitrate. .

[Examples 8 to 17] Using an enameled steel plate, ocher B2 glaze and blue 83 glaze were used as the base glaze, and E1 to E5 glazes were used as the spotted parts.Other than that, glaze was applied and fired under the same conditions as in Example 1. As a result, metallic-like enamel products having various spot colors shown in Table 4 were obtained, although the ground color was different due to the base glaze.

[Examples 18 to 20] and [Comparative Example] In order to investigate the influence of the content of metal nitrate, the iron nitrate content a was 0.05.
Spotted portions E8 to EIG within the range of ~2.0 parts by weight;
Using spotted areas E7 and Ell outside of this range, an enameled steel plate was subjected to FM firing under the same conditions as in Example 1. As shown in Table 4, Examples 18 to 10 using spotted areas E8 to E10 In No. 20, although there was a difference in color density depending on the iron nitrate content a, an almost uniform matte enamel layer with white brassy small spots was formed in all cases, whereas in the spotted areas E1 and Ell. In Comparative Examples 1 and 2 using
The former is simply a milky speckled pattern with no metallic coloration, while the latter has many microbubbles in the speckled areas.
Only products with inferior appearance were obtained.

[Example 211] Next, in order to see the influence of the base glaze, in contrast to Example 1, in which the spotted areas were glazed after the base glaze was fired, glaze A was applied and fired, and then 81 base glaze was applied on one side in a semi-dry state. Then, on top of this, the spotted part E1 is glazed in a small spot shape by spraying.
When fired at 00° C. for 5 minutes, a metallic-like enamel product having a white brass-like small speckled pattern similar to that of Example 1 was obtained.

[Example 22] A pure copper plate was used as the enamel substrate, one side of the copper plate was glazed with white C1 base glaze, and small spots were formed by D55 spot spray on the glossy enamel layer which was fired at 600°C for 10 minutes. When the product was glazed and fired at 600° C. for 10 minutes, a metallic-like enamel product having a white brass-like small speckled pattern similar to that of Example 1 was obtained.

[Examples 23 to 26] Next, an aluminized steel plate was used as the enamel substrate, and base glazes C1 to C4 were applied and fired, and speckled portions 05 to D8 were glazed in small speckled shapes by spraying in the combinations shown in Table 4. It was then fired. Both the base glaze and the spots are fired at 580℃.
I did it for a minute. The resulting enamel product has slightly raised spots due to the lower firing temperature compared to iron enamel, and is somewhat lacking in smoothness. As shown in Table 4, it was a metallic-like product with a white brass-like or aluminum-like small speckled pattern.

Regarding the products (test pieces) obtained in each of the above examples, the acid resistance (using 10% citric acid) was determined according to J15R-4301 "Quality Standards for Enamel Products" as a performance test, and it was found to be A grade or AAvA. , no difference from the base coat (a glossy enamel layer made of base glaze) was observed.

Also, as a stain resistance test, when I rubbed a line drawn with a black marker board marker with a dry cloth, it cleaned beautifully with no difference from the base coat.

(See the margin below.) As explained above, according to this invention, inexpensive raw materials can be used without impairing the smoothness, chemical resistance, stain resistance, adhesion, etc. of the enamel layer. , it is possible to economically provide a metallic-like enamel product having a small speckled pattern exhibiting a metallic color depending on the metal component of the metal nitrate.

[Brief explanation of the drawing]

FIG. 1 is a partially enlarged plan view of an enamel product showing an embodiment of the present invention. 1...Glossy enamel layer, 2...Small speckled enamel layer, 3...Hallow wax product.

Claims (1)

[Claims] A glossy enamel layer is provided on an enamel substrate, and on this enamel layer, one metal selected from Fe, Ni, Co, Cu, and Mn is added to 100 parts by weight of the frit for forming the matte enamel layer. An enamel product having a metallic-like small speckled pattern, characterized by having a small speckled enamel layer made of a fired enamel glaze to which 0.05 to 2 parts by weight of nitrate has been added.