JPS62240799A - Formation of colored pattern of aluminum - Google Patents

Abstract

PURPOSE:To easily form a uniform colored pattern of free designs by subjecting an Al material to machining with a polishing material in the state of applying a partially transparent masking thereon, then subjecting the material to treatments such as anodic oxidation, electrolytic coloring and resin coating after a specific pretreatment etching. CONSTITUTION:The surface of the Al material is cleaned by degreasing, etc., and is subjected to the partial transparent masking by a resin film, etc., having a desired pattern. Such material is subjected to the machining of the polishing material by a blasting or polishing treatment. The material is then subjected to the pretreatment etching by immersing the same in an aq. soln. of 40-65 g/lNaOH for >=1min and within 3min; thereafter, the respective treatments; the material is subjected to the anodic oxidation by an aq. soln. of a sulfuric acid, etc., the electrolytic coloring in an aq. soln. of the metallic salt of Ni, etc., and the coating of the acrylic melamine resin by the conventional practices. The desired color pattern is easily and surely obtd. by the above-mentioned method.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for producing a colored pattern on aluminum, which produces a colored pattern on the surface of aluminum or an aluminum alloy (hereinafter abbreviated as aluminum).

(Background Art) Conventionally, a method is known in which an anodic oxide film is formed on aluminum, then masked and electrolytically colored (for example, Japanese Patent Publication Nos. 59-5677 and 61-910).
There is also a known method in which after masking the aluminum base, an anodic oxide film is formed, and then electrolytically colored (Japanese Patent Publication No. 57-19757) Furthermore, unevenness is formed on the aluminum base or anodic oxide film by blasting, A method is also known in which the entire surface is satin-finished by diffused reflection.

However, pattern generation using electrolytic coloring method.

Because this is due to an electrochemical reaction.

Depending on the type of masking and the conditions during electrolysis, the finish will be affected and the finish will be complicated.b On the other hand, when performing a satin finish by blasting, it is not possible to perform anodizing or painting using conventional methods. That is, the etching process using sodium hydroxide, which dissolves the aluminum surface, is expected to be the bottleneck. Etching is performed for the purpose of removing surface defects such as surface scratches during the pre-molding process and improving the finished appearance after surface treatment, but if etching is omitted, the yield will be poor. It is also possible to perform etching before plastination, but it requires removing the aluminum from the surface treatment process once it has been suspended from the frame, applying it to the plate, and then returning it to the surface treatment process again, which reduces workability. decreases dramatically. For this reason, there is a drawback that new equipment must be introduced in order to perform etching in advance.

(Object of the Invention) The present invention eliminates these conventional drawbacks, performs blasting, and uses all conventional surface treatment processes to easily and reliably create a desired colored pattern on aluminum. That is.

(Structure of the Invention) The present invention employs abrasive processing of patterned parts by simple mechanical processing such as plasting or abrasive processing. ,
In particular, it produces beautiful colored patterns on aluminum by controlling etching during pre-treatment.

That is, in the present invention, a cleaned aluminum material is subjected to partial transmission masking and subjected to mechanical processing of an abrasive material by blasting or polishing treatment, and then immersion treatment in a 40 to 65 y/l aqueous sodium hydroxide solution. A method for producing colored patterns on aluminum electrical materials, which is characterized by pre-treating for a period of 1 minute to 3 minutes, followed by anodizing, electrolytic coloring in a metal salt-containing aqueous solution, and hyacrylic melamine resin coating. The gist is the method.

The present invention will be further explained in detail below.

The aluminum material used in the present invention is generally JI
SH6063 is often used for building materials, but it is not limited to this, and any type of aluminum can be used. Of course, this aluminum material may be an extruded elongated material or a plate material, and its shape is not particularly limited as long as it can be subjected to a blast treatment or a polishing treatment.

The present invention cleans the surface of aluminum material by degreasing etc.
First, partial transmission masking is applied.

Masking is performed by using a resin film, printing, etc. as usual. At this time, in accordance with the desired pattern, masking is performed so that the colored pattern part is partially transparent, and the other parts are masked.

After applying this partial transmission masking, a blasting or abrasive treatment is performed, and mechanical processing of the abrasive material is performed. In this case, the abrasive material is not limited to metals such as shot, cast iron, steel grid, non-metallic inorganic materials such as clay, carporundum, glass powder, etc., but also organic materials such as plastic beads are widely used.

However, in order to fully obtain the full processing effect of the abrasive, it is better to use a hard abrasive with a very acute angle.

By using a fine abrasive and increasing the supply pressure against the aluminum, it can be made to bite into the aluminum, but in the present invention, it is only necessary to mechanically process the surface irregularities, and the particle size does not necessarily matter. .

This abrasive material processes aluminum by blasting or polishing. The plast of the present invention is made by spraying or hammering an abrasive onto aluminum using compressed air. Air-only methods such as dry honing and liquid honing, or centrifugal projection methods that rely on centrifugal force may be used, but since the workpiece aluminum is generally long or large, it is better to use air-only methods in terms of equipment. , which is also desirable for efficiency.

Further, polishing involves bringing an abrasive material into contact with aluminum and rubbing it, and various methods such as rotation, centrifugal rotation, and reciprocating motion are used. However, for the same reason as blasting, a rotary or reciprocating type blasting process is preferable, but since it is applied to partially transparent masked aluminum, it is more optimal to use an air-type blasting process.

During blasting or polishing, force and pressing force are required to spray aluminum, which can be mechanically processed, and the spraying pressure when performing this blasting process varies depending on the type and shape of the abrasive, but is approximately 3 to 5 mL. K? /- or more, preferably 4 to 9/
- or more is required. Of course, in practice, the optimum conditions may be set depending on factors such as the equipment abrasive material fffl m.

After blasting or polishing, a partial transmission masking strips it away from the aluminum surface. Peeling and removal can be carried out chemically, but from the standpoint of protecting the processed aluminum surface, it is more desirable to carry out the removal physically.

This aluminum is then subjected to a surface treatment. After degreasing and washing with water, the etching is carried out using the conventional method (50Y/
When etching is carried out using an aqueous solution of sodium hydroxide, the mechanically processed pattern loses almost all of its value as a pattern, even if it is slightly visible.

In the present invention, as a reference for the entire 50'i/1 aqueous solution of sodium hydroxide, as much as possible, without using another concentration-1 solution,
As a result of intensive research into the conditions possible with existing general equipment, 40
~65! i' // The best results could be obtained by controlling the time in the sodium hydroxide aqueous solution for 1 minute or more and 3 minutes or less. If a concentration amplifier or other aqueous solution were used, special treatment would be required on the surface treatment equipment, which would be a bottleneck in the generalization of the equipment, so this was the result of research to avoid this.

Under these conditions, the purpose of etching is substantially achieved and the pattern is retained. However, if it exceeds 3 minutes, the pattern condition will deteriorate. Note that the most desirable state as a pattern is within 2.5 minutes, especially within 2 minutes.

On the other hand, if the etching time is less than 1 minute, the etching condition is insufficient and has no meaning.

After the above-mentioned etching, it is washed with water, then anodized in a sulfuric acid aqueous solution by a conventional method, and then, after washing with water, in the present invention, electrolytic coloring is always performed in a metal salt aqueous solution. On this occasion,
It goes without saying that it is possible to obtain a desired color depending on the type and concentration of the metal salt, but in general, if a bronze color is created using a nickel salt, it is necessary to add a pattern to the current monochromatic bronze color. can.

After electrolytic coloring, the product is washed with water or hot water, and then painted with acrylic melamine paint.

At this time, various types of dipping coatings as well as electrodeposition coating are of course used for the coating, but the acrylic melamine coating film may also be subjected to a matting treatment using a matting paint or a matting process. It goes without saying that it should be baked after painting.

What is obtained by the present invention is a colored pattern in which gray is added to the coloring of the aluminum masking portion. This is because surface irregularities are formed on the aluminum surface by mechanical processing of an abrasive material.

This is a pattern caused by diffused reflection from the patterned portion, which is left intact until the painting process.

(Effects of the Invention) In contrast to the conventional pattern generation technology, the present invention first performs partial transmission masking and then mechanically processes the abrasive material by blasting or polishing. In etching, the immersion treatment in a 40 to 6 o9/l aqueous sodium hydroxide solution was limited to a period of not less than 1 minute and not more than 3 minutes. Because of this, the pattern generation is mechanical.

It eliminates pattern restrictions and allows you to easily and reliably obtain a uniform colored pattern.Since new etching equipment is not required, existing surface treatment equipment can be used as is, with only time restrictions, and can be installed along with other equipment. It maintains its versatility and can be processed simultaneously with other single-blue products and non-colored products by simply operating the crane based on time management.

The resulting aluminum coloring pattern is subdued.
It is a colored pattern of the same type of gray applied to a young aluminum base, and the design can be freely chosen, and the colored pattern can be made into a uniform color with no color unevenness.

(Example) JIS H6063 aluminum plate materials were subjected to partial transparent masking in the form of a grid using a resin film, and alumina abrasive material with a particle size of 80 degrees (80 mesh) was sprayed onto this using a pressure of 4 to 9/-. After blasting by honing method, then degreasing and washing with water, dissolved aluminum amount is 20-30 y/l, temperature is 5Q"C, 55 g/l
in aqueous sodium hydroxide solution for 30 seconds, 1 minute, 2 minutes, 3
The samples were immersed for 1 minute, 4 minutes, and 5 minutes, respectively, and then anodized using a conventional method, electrolytically colored in an aqueous solution containing nickel salt, and then painted with an acrylic/melamine paint.

The results at this time were as follows.

(Note) - Samples A, B, and C are the names of samples that were run three times each in order to see the variation under the same conditions.

-Evaluation was based on visual appearance, comprehensively looking at the pattern condition and enochink condition, and a 4-level evaluation was performed with ◎ as extremely good, O as good, Δ as very poor, and × as poor.

Claims (1)

[Claims] The cleaned aluminum material is subjected to partial permeability masking and subjected to mechanical processing of the abrasive material by blasting or polishing treatment, and then immersed in a 40 to 65 g/l sodium hydroxide aqueous solution for 1 minute to 3 minutes. 1. A method for producing a colored pattern on an aluminum profile, which comprises performing pre-etching under the following conditions, followed by anodizing, electrolytic coloring in an aqueous solution containing a metal salt, and acrylic melamine resin coating.