JPS5947027B2 - Patterned surface treatment method for aluminum - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a novel surface treatment method for producing various colored patterns such as wood grain patterns on the surface of aluminum.

In this specification, aluminum is a general term for aluminum and aluminum alloys.

Traditionally, this method has been used to create patterns on the surface of aluminum, which is used as a building material and has a complex cross-sectional shape.
Various methods have been proposed for creating patterns on the surface of aluminum by immersing the aluminum before anodizing treatment in a certain liquid and applying electricity. In this method, hydrogen gas generated on the surface of aluminum due to the energization process forms a triumphal upward movement on the surface of the aluminum.

However, the generation of hydrogen gas during the energization process is not always constant and is extremely irregular, making it impossible to produce a consistent and regular pattern on the surface of aluminum, and also making it impossible to reproduce the same pattern. It has some inconveniences. In addition, since the pattern created by this method depends on the upward trajectory of hydrogen gas, only a monotonous line pattern or wood grain pattern can be obtained, and it is not possible to obtain a pattern suitable for the exterior design depending on the use of aluminum. There are inconveniences that cannot be avoided.

``On the other hand, if you want to create a free pattern, there is nothing better than the general printing method, but it has a problem that it cannot be applied to aluminum for building materials, which has a complicated cross-sectional shape. Therefore, the present invention provides a patterned surface treatment method that can generate not only a monotonous line pattern but also a free design similar to the printing method even on aluminum for building materials having a complicated cross-sectional shape. It is a product that has been devised with unique ingenuity for the purpose of doing so.

That is, in the method of the present invention, an adhesion promoter for the above-mentioned printing substance whose main component is an organic substance is applied to the printed surface of a thin film that has been preprinted with a suitable pattern of a substance that inhibits etching or chemical polishing in the subsequent process. The above-mentioned printing is achieved by bringing the thin film into close contact with the surface of the aluminum by hydraulic pressure, adhering the above-mentioned printing substance to the surface of the aluminum, and then removing the above-mentioned thin film and subjecting the aluminum to an etching process or a chemical polishing process. A non-etched or chemically polished surface of the part to which the substance is attached and an etched or chemically polished surface to which the printed substance is not attached are formed, and then, after the printing substance is removed, a colored anodic oxide film is formed on the surface of the aluminum. It is characterized by generating.

This can be simply expressed as a process as follows.

The method of the present invention removes 7 substances that inhibit etching and chemical polishing.
The important technical idea is to attach the material to the surface of aluminum and to perform etching or chemical polishing with the substance attached, but the substances that inhibit etching and chemical polishing are acid resistance and resistance. Resist materials such as various alkaline resist inks.

Various design patterns are printed on thin films using such materials.

As the thin membrane, a film-like membrane that is soluble in hot water and certain chemicals is used. When adhering the above-mentioned material printed on the thin film to the surface of aluminum, a method of pressing the thin film using hydraulic pressure is used.

In this process, aluminum is pressed onto a thin film floating on a liquid and submerged in the liquid, and the liquid pressure at this time causes the thin film to adhere uniformly to the surface of the aluminum. However, simply adhering a thin film to the aluminum surface does not allow the printing substance to adhere to the aluminum surface.
In the present invention, an adhesion promoter is applied to the printed surface of the thin film in order to ensure that the printed substance on the thin film adheres to the aluminum surface.

The term "adhesion promoter" here refers to a material that swells the printed material on the thin film. It moisturizes the film and makes it easier to peel off from the thin film, making it easier to adhere to the aluminum surface.It is a chemical whose main component is an organic substance, such as organic solvents such as phthalate esters and trichlene. It will be done. Such an adhesion promoter naturally adheres to the aluminum surface along with the printing material when a thin film is brought into close contact with the aluminum surface using hydraulic pressure, but it cannot be removed during post-process etching or chemical polishing. Since it sometimes dissolves, it does not interfere with etching or chemical polishing.

Note that after the thin film is brought into close contact with the aluminum surface and the printing substance is attached, the thin film is removed by appropriate means.

The etching treatment in the present invention includes sodium hydroxide,
It is carried out in common alkaline and acidic aqueous solutions such as potassium hydroxide, hydrochloric acid, and ferric chloride, and chemical polishing is also carried out in baths such as phosphoric acid/sulfuric acid solutions and phosphoric/nitric acid baths.

The processing conditions are the same as those required for normal etching and chemical polishing.

In this etching process (or chemical polishing process), the adhesion promoter is dissolved and lost from the aluminum surface as described above, and etching (or chemical polishing) is performed on the areas of the aluminum surface to which the printed material is not attached; For areas where the printed material is attached, the printed material may be etched (
Etching (or chemical polishing) is not performed because it has an inhibitory effect on etching (or chemical polishing).

In other words, the effect of etching (or chemical polishing) differs depending on whether or not a printing substance is attached, and there are non-etched areas (or non-chemically polished areas) and etched areas (or chemically polished areas) on the aluminum surface. be.

Thereafter, the printing substance is removed, using an organic solvent such as thinner or other removing agent as appropriate.

In this way, the etched part (or chemically polished part)
After forming a non-etched part (or a non-chemically polished part), a colored anodic oxide film is formed on the surface of the aluminum.

For the production of a colored anodic oxide film, a so-called electrolytic coloring method is used in which the anodic oxide film is formed on the aluminum and at the same time it is colored.Alternatively, once the anodic oxide film is formed, it is electrolytically treated in a coloring bath containing metal salts. A so-called electrolytic coloring method is used.

The anodic oxide film treatment is appropriately carried out by a conventionally known method. When a colored anodic oxide film is formed on the surface of the aluminum, the state of gloss on the surface of the aluminum differs depending on the presence or absence of the etching treatment effect (or chemical polishing treatment effect). Differences in color tone appear, and this creates a pattern.

That is, the difference between the areas to which the printing substance is attached and the areas to which it is not attached results in a pattern.

Since this printing material is printed on a thin film in advance as mentioned above, it is possible to design any pattern, and after all, any pattern can be created even on aluminum with a complex cross-sectional shape. can be generated.
In addition, since an adhesion promoter is applied to the printed surface of the thin film and then adhered to the aluminum surface, a large number of thin films with appropriate patterns printed in advance can be produced in large quantities, allowing the same pattern to be produced in large quantities. It has the advantage of being able to

Examples of the present invention will be described below.

Example 1 After degreasing and cleaning aluminum alloy A6O63S by immersing it in 10 wt% nitric acid, acid-resistant resist ink 873 was applied.
An adhesion promoter is applied to the printed surface of a thin film printed with (trade name manufactured by Hanami Chemical Co., Ltd.) as a wood grain pattern to ensure easy and reliable adhesion of the resist ink, and the thin film is floated on the liquid. The aluminum alloy is brought into close contact with the aluminum alloy by hydraulic pressure, and the wood grain pattern is adhered to the surface of the aluminum alloy.

Next, after removing the thin film on the surface of the aluminum alloy with hot water, it was placed in an aqueous solution containing 200 t/t of ferric chloride at 30°C.
, etching treatment is performed for 5 minutes.

Then, when the resist ink of the wood grain pattern was removed with an organic solvent, an aluminum alloy with etched portions other than the wood grain pattern was obtained.

This aluminum alloy was mixed with sulfuric acid at 150t/T and bath temperature at 20°C.
After anodizing for 30 minutes at a current density of 1.0 A/Dm2, it was connected to a cathode in a bath of nickel sulfate 3011 and boric acid 309/l and heated at 20°C. C. When electrolyzed for 1 minute under 2OV conditions, it was colored bronze, but the color tone was different depending on the etched and non-etched areas, and a wood grain pattern was drawn based on the difference in color tone.

Example 2 An aluminum plate Al2OOP was immersed in 10 wt% nitric acid, degreased and cleaned, then immersed in 5 wt% sodium hydroxide solution (liquid temperature 50°C) for 5 minutes for etching treatment, and then etched in 10 wt% nitric acid. Remove smut by soaking it in water.

On the other hand, the acid-resistant resist ink Kitanabe Epicorton▲1
3 (trade name, manufactured by Tanabe Chemical Co., Ltd.), an adhesion promoter is applied to the printed surface of a thin film printed in an arbitrary pattern, and this thin film is floated on a liquid and applied to the surface of the aluminum plate using liquid pressure. At the same time, the pattern is attached to the surface of the aluminum plate.

Next, after removing the thin film on the surface of the aluminum plate with hot water, the aluminum plate was immersed in a chemical polishing solution consisting of concentrated sulfuric acid and concentrated phosphoric acid for 5 minutes, and the other parts except for the part to which the pattern was attached were polished.

After removing the resist ink on the surface of this aluminum plate with an organic solvent, it was anodized under the conditions of sulfuric acid 150y/t, bath temperature 20℃, and current density 1.0A/Dm2, and further treated with sulfuric acid 10f/l and sulfuric acid. In a coloring bath at 10 r/t, 20
℃、A. C. When electrolytically treated for 1 minute under 15V conditions, a colored film of upper color was formed on the surface of the aluminum plate, but the color tone differed depending on the chemically polished area and the non-chemically polished area, and a shading pattern was created due to the difference in color tone.

Example 3 An adhesion promoter was applied to the printed surface of a thin film printed with an arbitrary pattern using alkali-resistant ground ink for printed wiring, and aluminum alloy A6O63S, which had been degreased and cleaned by immersion in 10 Wt% nitric acid, was placed on top of the liquid. By pressing and submerging the floating thin film, the thin film is brought into close contact with the surface of the aluminum alloy using hydraulic pressure, and the pattern is attached.

Next, the aluminum alloy from which the thin film had been removed with hot water was heated at 50°C for 10 minutes in a 5 wt% sodium hydroxide solution.
After performing an etching process for 1 minute, the acid line gland ink for printing is removed using an organic solvent. An aluminum alloy was obtained in which the areas to which the ground ink was attached were not etched, but the other areas to which the ground ink was not attached were etched.

Add sulfuric acid to this aluminum alloy at 150y/ι and bath temperature at 20°C.
After anodizing for 30 minutes at a current density of 1.0 A/Dm2, the aluminum alloy was connected to the cathode in a coloring bath consisting of 10 t/t of manganese sulfate and 10,000 t of hydrogen peroxide. Bath temperature 20℃, D. C. When electrolytically treated at 35 V for 30 seconds, the surface of the aluminum alloy was colored golden yellow, but the color tone differed between the etched and non-etched areas, and a shading pattern was created due to the difference in color tone. Example 4 Similar to Example 1, resist ink was applied to the surface of aluminum alloy A6O63s and the thin film was removed, followed by incubation in a cupric chloride 100'i'/ι solution at 35°C for 2 minutes. Perform etching treatment.

Next, when the resist ink was removed with an organic solvent, an aluminum alloy was obtained in which the resist ink-adhered areas were not etched, but the resist ink-unattached areas were etched. This aluminum alloy was treated in a 10 wt% sodium hydroxide solution at 45°C for 7 minutes, and then treated with sulfuric acid at 150 y/t, bath temperature at 20°C, and current density at 1.
．． Anodic oxidation treatment is performed under the condition of 0A/Dm2.

Claims (1)

[Claims] 1. Apply an adhesion promoter for the above-mentioned printing substance mainly composed of organic matter to the printed surface of a thin film pre-printed with an appropriate pattern of a substance that inhibits etching or chemical polishing in the post-process, and then apply an adhesion promoter for the above-mentioned printing substance, which is mainly composed of an organic substance, The printing material is adhered to the surface of the aluminum by hydraulic pressure, and then the thin film is removed and the aluminum is subjected to an etching treatment or a chemical polishing treatment, so that the portion to which the printing material is attached is not etched. forming a surface or a non-chemically polished surface and an etched surface or a chemically polished surface of the part to which the printing substance is not attached, and then forming a colored anodic oxide film on the surface of the aluminum after removing the printing substance. A patterned surface treatment method for aluminum.