JPH06170336A - Manufacture of coated metal material - Google Patents

Abstract

PURPOSE:To improve the resistance to corrosion of a recessed and projected pattern formed on a coated metal material on which fine recessed and projected pattern is formed. CONSTITUTION:When a coating material 3 composed of a silicone compound as main component is applied on the surface of a metal material 1 with fine recessed and projecting pattern 2 formed at least on a part of the surface, the viscosity of the coating material 3 is set in the range of 1-1000 centipoise so that the coating material 3 applied on the metal material 1 is also filled in the recessed sections of the recessed and projecting pattern 2 of the metal material 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a coated metal body which is coated on the surface of a metal body having a fine uneven pattern.

[0002]

2. Description of the Related Art Recently, in consideration of the scenery of a city or a house, as a fence for roads and balustrades, a building material for interior and exterior of buildings, etc., a fine uneven pattern having a decorative property such as a hairline and a grain on the surface. The metal body formed with is widely used.

In consideration of corrosion resistance, stainless steel materials, surface-plated steel materials, aluminum materials and the like are used as the metal bodies, and these metal bodies are particularly used outdoors for the above-mentioned purposes. And, dust and the like are likely to adhere to fine uneven patterns such as hairlines and textures formed on the surface of these metal bodies to easily get into a wet state. Rust sometimes occurred on the uneven pattern.

[0004]

In order to solve the above problems, the surface of the metal body on which the fine uneven pattern is formed is coated with a transparent paint such as acrylic silicone resin, acrylic resin, urethane resin, etc. It has been attempted to improve the corrosion resistance of uneven patterns by blocking the contact between corrosive factors such as dust and acid rain and the metal body while making the most of the decorativeness of the body surface. However, a coating film made of the above-mentioned acrylic resin, urethane resin, or the like deteriorates over time and has a problem in stain resistance.

On the other hand, a coating film made of an acrylic silicone resin paint is suitable for the above-mentioned applications because it is hardly deteriorated with time and has excellent stain resistance. Since the paint was applied in a relatively high viscosity state of 1500 to 5000 centipoise, the concave portion of the uneven pattern 2 formed on the surface of the metal body 1 as shown in FIG. Since it is only adhered to, the formed coating film has a drawback that it is easily peeled off in a short period of time.

The present invention solves the above-mentioned problems that the conventional method for producing a coated metal body has, and improves the corrosion resistance of a fine uneven pattern formed on the surface of the metal body. It is intended to provide a manufacturing method.

[0007]

In order to achieve the above object, the present invention has the following constitution. That is, the method for producing a coated metal body according to the present invention is a coated metal body in which a coating material containing a silicone compound as a main component is coated on the surface of a metal body having a fine uneven pattern formed on at least a part of the surface. A method for producing a body, wherein the viscosity of the paint is 1
It is made to be 1000 centipoise, and is characterized in that the coating material applied on the surface of the metal body is also filled in the concave portions of the metal body.

The structure of the present invention will be described in more detail below.

As the metal body used in the present invention, generally, steel, aluminum, copper, zinc, other metals and their alloys are appropriately used, but stainless steel, galvanized steel, aluminum having excellent corrosion resistance. Etc. are particularly preferably used. Further, the shape of the metal body may be any shape such as a flat plate shape, a curved plate shape, a corrugated plate shape, or a columnar shape such as a prism or a column. It may have a modified cross section.

The fine concavo-convex pattern formed on the surface of the metal body may be a non-decorated one such as a streak generated when the metal body is molded, but generally a fine decoration such as a hairline or a grain. It has an uneven pattern having properties. The concavo-convex pattern may be formed on the entire surface of the metal body or may be formed on a part thereof. The depth of the concave and convex portions may be shallow, but is preferably deep.

The surface of the metal body is preliminarily subjected to a degreasing treatment to remove dirt and oils, and a phosphate coating film such as a phosphate coating is formed by chemical conversion treatment in order to improve the adhesion to the paint. Or a known primer layer may be formed.

The paint to be applied to the surface of the metal body contains a silicone compound as a main component and is prepared by mixing the silicone compound with an anti-settling agent, a modifier, a solvent and the like. Is. As a silicone compound, generally, an organic silicon compound alone or an organic silicon compound having a cycloxane bond as a main chain of a silicone resin or the like and an alkyd, epoxy, acrylic, polyester,
One such as a silicone sol obtained by reaction with a modified organic substance such as phenol, melamine or urethane is preferably used, and the coating material may be a room temperature curing type or a baking type, but may be heat cured. Generally, a baking mold which can shorten the curing time is preferably used.

When the above-mentioned silicone sol is used, an acrylic-modified silicone sol obtained by condensing an alkylol group, which is a functional group of a thermosetting acrylic resin, with an organosiloxanol or an organosiloxane is a metal body. Since it has excellent adhesion, weather resistance and chemical resistance and is heat-cured, it is more preferably used.
Further, it is preferable that the content of the modified organic substance is smaller than that of the organic silicon polymer, because the weather resistance and the adhesion are excellent, and the gas generation amount during combustion is small.

The paint containing the silicone compound as a main component may be colored, but if it is made transparent, the surface of the metal can be seen through even if the paint is applied to the surface of the metal. It is preferable because the appearance of the uneven pattern is not impaired.

When a paint containing the silicone compound as a main component is applied to a metal body, the viscosity of the paint is 1 to 10
The reason why the pressure is set to 00 centipoise is that when the viscosity is 1 centipoise or less, it is difficult to form a coating film because the silicone compound is minute, and when it is 1000 centipoise or more, the viscosity is high. Is not filled well. The suitable range of the viscosity is 2 to 100 centipoise.

For coating the surface of the metal body with the above-mentioned coating material, known methods such as sub-coating, brush coating, roller coating and the like are applied, and the film thickness obtained by the coating is not particularly limited, but in general, It is about 5 to 50 μ.

[0017]

In the method for producing a coated metal body of the present invention, the surface of the metal body is coated with a paint containing a silicone compound as a main component,
This is a method for producing a coated metal body having excellent corrosion resistance and stain resistance due to the excellent water repellency, weather resistance, chemical resistance, etc. possessed by the silicone compound which is the main component of the coating material. When coating on the surface of the paint, the viscosity of the paint is 1
The viscosity is as low as 1000 centipoise, and the paint applied to the surface of the metal body is filled in the concave and convex portions of the metal body. It is possible to obtain a coated metal body that is firmly attached and has excellent corrosion resistance and stain resistance of the uneven pattern portion.

[0018]

EXAMPLES The present invention will be specifically described below based on examples. 1 is a cross-sectional explanatory view showing an embodiment of a coated metal body manufactured by the method for manufacturing a coated metal body of the present invention.

First, as shown in FIG. 1, the surface of a metal body 1 made of a stainless steel plate (SUS304) having an uneven pattern 2 formed by a hairline having a roughness of 400 is degreased and washed with water, and then the viscosity of the surface is 5. 5 centipoise (20
The present invention in which a bake-curable coating 3 (Super Cera TS-401 manufactured by Daihachi Kagaku Co., Ltd.) containing a silicone compound as a main component is applied, and the coating is solidified to form a coating film having a thickness of 15 to 20 μm. A coated metal body according to Example 1 was obtained.

Further, the surface of the metal body 1 made of an aluminum plate having the unevenness pattern 2 formed by the hairline of roughness No. 400 on the surface is degreased and washed with water, and then the surface has a viscosity of 5
After applying a room temperature curable coating 3 (Ceraprotex manufactured by Tonensha Co., Ltd.) containing 00 centipoise (20 ° C.) of a silicone compound as a main component, the coating was solidified to form a coating film of 10 to 15 μ. A coated metal body according to Example 2 was obtained.

Next, as a comparative example, the surface of a metal body made of an aluminum plate similar to that of the above-mentioned Example 2 had a viscosity of 3000.
After applying a bake-curable paint (manufactured by Natco Paint Co., Ltd.) containing an acrylic silicone compound having a centipoise (20 ° C.) and high viscosity as a main component, the paint is solidified to 15 to 2
A coated metal body on which a 0 μ coating film was formed was obtained.

Next, the coated metal bodies of Examples 1 and 2 and Comparative Example were subjected to a cross-cut tape peeling test, a cross-cut tape peeling test after a boiling test, and a salt spray test in order to examine the corrosion resistance. The results are shown in Table 1.

In the cross-cut tape peeling test, 1 mm × is caused by a cut that penetrates the coating film of the test piece and reaches the surface of the metal body.
This is a test to examine the number of squares remaining without peeling when 100 squares of 1 mm are made and the cellophane adhesive tape is applied on the squares and then the tape is forcibly peeled off. The subsequent cross-cut tape peeling test is a test in which the above-mentioned cross-cut tape peeling test is performed after boiling for 10 hours. In Table 1, all of the original grid numbers, 100, remain as the denominator and do not peel off. The number of eyes is indicated by the numerator.

In the salt spray test, a sharp knife is used to draw two diagonal lines intersecting each other due to a cut that penetrates the coating film of the test piece and reaches the surface of the metal body, and the test piece is subjected to a salt water mist. It is a salt spray test in which the size of blisters formed on the coating film is examined by evaluating the adhesion between the coating film and the metal body by putting it in the container for 1,000 hours, and ○ in Table 1 indicates that rust and blistering have occurred. Not observed, x indicates that rust and blistering were observed.

[0025]

[Table 1]

As shown in Table 1 above, the coated metal bodies according to Examples 1 and 2 of the present invention are found in the results of the cross-cut tape peeling test, the cross-cut tape peeling test after the boiling test, and the salt spray test as compared with the comparative example. Thus, it was found that the adhesion between the coating film and the metal body was excellent.

[0027]

As described in detail above, in the method for producing a coated metal body of the present invention, the surface of the metal body is coated with a coating material containing a silicone compound as a main component, and the silicone compound which is the main component of the coating material has excellent properties. This is a method for producing a coated metal body having excellent corrosion resistance and stain resistance due to water repellency, weather resistance, chemical resistance, etc. Further, when the coating material is coated on the surface of the metal body, the viscosity of the coating material is 1 The viscosity is as low as 1000 centipoise, and the paint applied to the surface of the metal body is filled in the concave and convex portions of the metal body, so the paint is strong not only in the convex and concave portions of the concave and convex pattern. Attached to the
A coated metal body having excellent corrosion resistance and stain resistance of the uneven pattern portion can be obtained.

[Brief description of drawings]

FIG. 1 is a cross-sectional explanatory view showing an example of a coated metal body manufactured by a method for manufacturing a coated metal body of the present invention.

FIG. 2 is a cross-sectional explanatory view showing a coated metal body manufactured by a conventional method for manufacturing a coated metal body.

[Explanation of symbols]

 1 Metal body 2 Uneven pattern 3 Paint

Claims (1)

[Claims] 1. A method for producing a coated metal body, which comprises coating a coating containing a silicone compound as a main component on the surface of a metal body having a fine uneven pattern formed on at least a part of the surface thereof. A method for producing a coated metal body, wherein the viscosity of the coating material is 1 to 1000 centipoise, and the coating material coated on the surface of the metal body is also filled in the concave portions of the metal body.