JP3203895B2 - Surface treatment method of aluminum or its alloy - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for treating a surface of aluminum or an alloy thereof, and more particularly, to a pattern portion and / or a non-pattern portion formed on the surface of aluminum or an alloy thereof. The present invention relates to a method for forming an arbitrary coloring and / or coloring and enhancing a decorative effect of a writing instrument, a watch, a cosmetic container, and the like.

[0002]

2. Description of the Related Art Conventionally, as a method for forming an arbitrary colored pattern of alumite on aluminum, a resin layer having a high electrical insulating property is used, and an arbitrary pattern is formed by a screen printing method or a photoresist method. Is formed, the anodic oxide film on the portion where the resin layer is not formed (the pattern to be formed) is peeled off and anodized again, or the dyed alumite dye is immersed in nitric acid. There was a method of removing the dye and coloring again with the dye.

[0003] However, the screen printing method has a flat surface or a cylindrical shape such as a writing instrument, and can be easily formed with a relatively simple pattern. When an attempt is made to form a perfect pattern, problems such as crushing of the pattern portion due to bleeding of ink and crushing of joints occur, and also a curved surface, a spherical shape, a polygonal shape, In the case of a dimensionally curved surface, pattern formation was almost impossible.
In addition, the photoresist method can handle flat surfaces, but cannot support substrates having various surface shapes at present.

Recently, attention has been paid to the fact that carbon black efficiently absorbs YAG laser light, and YAG laser light and a coating material containing carbon black are applied to various base materials such as characters. Has been used for so-called marking. Specifically, an anodic oxide film is formed on aluminum or its alloy, a coating film is formed on the surface with a paint containing carbon black, and the coating film layer is removed with a YAG laser to form a pattern. Is an attempt to form

[0005]

Even if the coating layer containing carbon black is removed with a YAG laser to form a pattern, the surface of the pattern to be formed by the removal is thin. A transparent resin layer remains, and then this pattern is immersed in an aqueous solution of sodium hydroxide to remove the anodic oxide film. However, there is a problem that a thin transparent resin layer is formed on the surface and cannot be removed. It turned out to be.

Therefore, when the laser output is increased and processing is performed, although the resin layer can be partially removed from the pattern portion,
Incomplete, the underlying anodic oxide film is unevenly removed, or the underlying aluminum surface is exposed, or the resin layer is dissolved by high heat or peeling occurs. As a result, problems such as a decrease in pattern accuracy occurred.

[0007]

SUMMARY OF THE INVENTION Accordingly, the present invention has been made in view of these problems, and an object of the present invention is to provide a pattern portion and / or a pattern portion on aluminum or an alloy thereof for various surface shapes. It is an object of the present invention to provide a method for accurately and easily forming any coloring and / or coloring of the anodic oxide film on the non-patterned portion.
It has been found that a highly accurate multicolor anodic oxide film pattern can be formed by using a highly insulating resin layer capable of efficiently absorbing AG laser light and removing it with low output.

That is, according to the present invention, a porous anodic oxide film is formed on the surface of aluminum or an alloy thereof, and if necessary, after coloring, a resin layer having high electrical insulation containing a black oil-soluble dye is formed on the surface. Irradiating a YAG laser beam to remove the resin layer into an arbitrary shape; removing the porous anodic oxide film at the removed portion; and performing anodic oxidation again to form a porous anodic oxide film;
After coloring as required, the resin layer is removed, and a surface treatment method of aluminum or an alloy thereof formed by sealing is a first gist. A porous anodic oxide film is formed on the surface of aluminum or its alloy, After forming a resin layer having high electrical insulation containing a black oil-soluble dye on the surface, irradiating the resin layer with a YAG laser beam to remove the resin layer into an arbitrary shape, and coloring the porous anodic oxide film at the removed portion Then, the surface treatment method of aluminum or its alloy formed by removing the resin layer and performing a sealing treatment is referred to as a second method.
A porous anodic oxide film is formed on the surface of aluminum or its alloy, and after coloring, a resin layer having a high electrical insulation containing a black oil-soluble dye is formed on the surface, and the YAG layer is formed.
After irradiating the light and removing the resin layer to an arbitrary shape, the coloring material of the porous anodic oxide film is removed, and the porous anodic oxide film from which the coloring material has been removed is again colored with another coloring material. A third aspect of the present invention is to provide a method of surface-treating aluminum or an alloy thereof by removing a resin layer and performing a sealing treatment.

A method for forming a porous anodic oxide film on aluminum or an alloy thereof may be carried out by a known method. Specifically, sulfuric acid, phosphoric acid, chromic acid, oxalic acid, and carbonate are used as an electrolytic solution. , An aqueous solution of sodium hydroxide or the like, oxalic acid, sulfosalicylic acid, sulfophthalic acid, sulfomaleic acid, sulfosuccinic acid, sulfoytaconic acid,
An aqueous solution of a mixed acid obtained by adding sulfuric acid to sulfofumaric acid, malonic acid, or the like is used. As a current waveform used for anodization, direct current, pulse, PR, incomplete rectification, alternating current, and the like are used.

The obtained porous anodic oxide film is colored as required. The coloring method is a method of immersing in an aqueous solution containing an inorganic compound, a method of alternately immersing in two kinds of inorganic compounds, Method of immersion in a solution of acid dye, metal complex dye, acid mordant dye, oil-soluble dye, pores by applying alternating current and direct current, using an insoluble electrode such as carbon or platinum in the aqueous solution containing metal salt Various methods are used, such as a method of depositing a metal in a porous anodic oxide film.

Next, the resin layer having high electrical insulation will be described. The resin layer is formed by a coating or screen printing method, and is a property of a paint or a screen ink, which is dried or reacted and cured at room temperature, or cured by heating. Specifically, acrylic, polyester, epoxy, urethane, alkyd, vinyl, phenol, silicon, fluorine and the like are used.

Examples of the black oil-soluble dye include nigrosine-based black dyes and C.I. I. In the number, C.I. I. Acid
Black2, C.I. I. Solvent Black
5, C.I. I. Solvent Black 7, C.I. I.
Solvent Black 3, C.I. I. Solven
t Black22, C.I. I. Solvent Bla
ck23, C.I. I. Acid Black 123, and Oil Black BY, O
il BlackBS, Oil Black803, O
il BlackHBB, Special BlackEB,
Spirit Black AB (orient Chemical Industry Co., Ltd.), Aizen SplonBlack B
H, Aizen Splon BlackGSH sp
and Echial (above, Hodogaya Chemical Industry Co., Ltd.). The concentration may be about 5 to 30% by weight based on the solid content of the paint or the screen ink resin. If necessary, a coloring material having an absorption characteristic around 1060 nm may be added.

The coloring and / or coloring obtained according to the invention
The pattern form of coloring is that only the pattern part is colored or colored,
There are three types: coloring or coloring only the non-pattern portion, and coloring and / or coloring the pattern portion and the non-pattern portion.

[0014]

A film is formed on aluminum or an alloy thereof on which a porous anodic oxide film is formed by using a paint containing a black oil-soluble dye or a screen ink, and then treated with a YAG laser. Since the film can sufficiently absorb YAG laser light, an arbitrary pattern can be formed, and the pattern portion can be completely removed by the laser light, and the surface condition of the underlying porous anodic oxide film Since it is completely exposed without deteriorating, it is possible to easily perform the subsequent processing, and finally, it is possible to form various coloring and / or coloring patterns, and thus, writing instruments, cosmetic containers It can improve the appearance and design of watches and watches.

[0015]

【Example】

Example 1 A pipe made of aluminum (JIS 1080) having an inner diameter of 8 mm, a thickness of 0.2 mm, and a length of 100 mm was buff-polished and 5%
Etching at 50 ° C. for 1 minute with an aqueous solution of NaOH,
A neutralization treatment was performed with 30% nitric acid. Thereafter, using a 15% sulfuric acid electrolytic solution at 20 ° C. and a current density of 1.5 A / dm ² with platinum as a counter electrode, anodic oxidation was performed for 30 minutes to form a porous anodic oxide film. The film thickness was 10 μm. The insulating resin film was formed by the following method. Acrylic thermosetting paint (manufactured by Kansai Paint Co., Ltd., clear of Magiclon) was used as the paint, and the black oil-soluble dye was Nigrosine EX (Orient Chemical Industry Co., Ltd.)
15% by weight, based on the solid content of the coating resin, was dissolved and dispersed. The resulting solution was diluted twice with a special thinner and sprayed onto an aluminum pipe having a porous anodic oxide film formed thereon. And dried at 160 ° C. for 20 minutes.
It was formed to a thickness of μm. Next, output 28A with YAG laser
By processing into a 0.1 mm grid pattern with
The coating was removed with a width of 0.1 mm. Next, at 50 ° C. and 10% N
A laser-processed aluminum pipe is immersed in an aOH aqueous solution to remove the porous anodic oxide film in the pattern portion.
C., using platinum as a counter electrode in a 3% oxalic acid aqueous solution,
Anodization was performed at a current density of A / dm ² for 30 minutes to form a gold porous anodic oxide film of 10 μm in the pattern portion. Thereafter, the coating film was peeled off, immersed in ion-exchanged water at 90 ° C. for 30 minutes, and sealed to obtain a pipe having a ground aluminum color and a lattice pattern portion having a gold color. The gold pattern was 0.1 mm, and there was no collapse of the pattern.

Example 2 A 1 mm thick aluminum plate (JIS 1080) was
Etching was performed at 0 ° C. with a 5% aqueous solution of NaOH, and the resultant was immersed in 30% nitric acid for neutralization. Then sulfuric acid 15%, temperature 20
° C., to form the current density 1.5A / dm ^2, 30 minutes anodized porous anodic oxide film. Thereafter, 0.2% of a blue dye (Sanodal Blue G, manufactured by Sando Co., Ltd.)
It was immersed in an aqueous solution at a temperature of 70 ° C. and dyed blue. After drying,
A fluorine-based paint (Lumiflon LF200, manufactured by Asahi Glass Co., Ltd.) was used as the paint, and 20% by weight of a black oil-soluble dye, Oil Black BS (manufactured by Orient Chemical Industries, Ltd.), was added to the solid content of the paint resin. And dissolved and dispersed. Dilute 2 times with a special thinner, add 5% by weight of a special hardener to the resin solid content, apply with a sprayer,
By drying at 20 ° C. for 20 minutes, a resin layer having a thickness of 15 μm was formed. After that, a random pattern was formed with an output of 30 A using a YAG laser to completely remove the resin layer in the portion subjected to the random pattern processing. Next, the aluminum plate on which the random pattern is formed is
H. The porous anodic oxide film of the pattern portion, which was dyed blue, was removed. Next, anodizing treatment is again performed in a 15% sulfuric acid electrolytic solution to form a porous anodic oxide film on a random pattern portion. The counter electrode is made of platinum in an aqueous solution of 30 g / l nickel sulfate and 30 g / l boric acid. It was treated at 10 V for 10 minutes, and was colored black by depositing nickel on the porous anodic oxide film. Next, the coating film was removed, and sealing treatment was performed at 90 ° C. for 30 minutes with ion-exchanged water to obtain an aluminum plate having a blue background and a random pattern portion colored black.

Example 3 A porous anodic oxide film was formed by dyeing the aluminum plate used in Example 2 in blue under the same conditions as in Example 2. Epoxy ink (Seiko-1300, manufactured by Seiko-Advance Co., Ltd.) is used as a screen ink, and black oil-soluble dye Special BlackEB (manufactured by Orient Chemical Industry Co., Ltd.) is applied to the ink resin solids. ,
30% by weight was added and dissolved and dispersed with a triple roll. The entire surface was printed on a blue dyed aluminum plate by a screen printing method, and dried at 130 ° C. for 30 minutes to form a printed layer of 8 μm. Next, a spiral pattern was formed with a width of 0.2 mm using a YAG laser at an output of 32 A, whereby the resin layer was completely removed from the spiral pattern. Then 50
C. and immersed in 10% NaOH to remove the porous anodic oxide film in the spiral pattern. The aluminum surface of the spiral pattern is immersed in a 10% aqueous solution of ammonium fluoride at 50 ° C. to give a matte appearance, and is again anodized in a 15% sulfuric acid electrolyte to form a porous anodic oxide film. And red dye (Aluminium, manufactured by Sando Co., Ltd.)
(Red RLW) Dipped in an aqueous solution of 0.5%, 70 ° C. and dyed red, then the resin layer was peeled off, and ion-exchanged water, 90%
The aluminum plate was immersed at 30 ° C. for 30 minutes and subjected to a pore-sealing treatment to obtain an aluminum plate having a blue ground, a helical pattern portion and a matte red color.

Example 4 A porous anodic oxide film was formed from the aluminum material used in Example 1 under the same conditions as in Example 1, and a resin film was formed.
The processing conditions and patterns were performed under the same conditions. Then, a black dye (Aluminium Bl manufactured by Sando Co., Ltd.)
The dye is adsorbed on the porous anodic oxide film in the pattern section under the conditions of 1.0%, 60 ° C. for 10 minutes, and treated in ion exchanged water at 90 ° C. for 20 minutes. The porous anodic oxide film having a colored portion was sealed.
Thereafter, the resin layer was removed, and the sealing process was performed again to obtain an aluminum pipe whose background was colored aluminum and whose pattern was colored black.

Example 5 Using the aluminum plate used in Example 2, under the same conditions as in Example 2, a porous anodic oxide film, coloring, forming a resin film,
Laser processing was performed. Thereafter, an aluminum plate on which a pattern was formed was immersed in 30% nitric acid to remove the blue dye adsorbed on the porous anodic oxide film of the pattern. Then, a black dye (Aluminium, manufactured by Sando Co., Ltd.)
Black 2LW), 1.0%, 60 ° C., 10%
The black dye was adsorbed again to the porous anodic oxide film from which the blue dye had been removed after the treatment for minutes. Thereafter, the film was treated with ion-exchanged water at 90 ° C. for 20 minutes, and the colored porous anodic oxide film in the pattern was sealed. Then remove the resin layer,
By performing the sealing treatment again, an aluminum plate having a blue background and a black pattern was obtained.

Comparative Example 1 A black paint in which carbon black was dispersed (acrylic thermosetting paint, manufactured by Kansai Paint Co., Ltd.) was used in place of the paint used in Example 1. Went the same way,
The porous anodic oxide film of the laser-processed pattern part is 1
It cannot be removed even when immersed in 0% NaOH aqueous solution.
Even when the anodic oxidation treatment was performed in the oxalic acid electrolyte, a golden porous anodic oxide film could not be formed.

Comparative Example 2 Instead of the screen ink used in Example 3, a black ink in which carbon black was dispersed (Seiko Advance Co., Ltd.)
Except that the porous anodic oxide film in the pattern portion could not be removed, and a spiral pattern could not be formed.

In the above Examples and Comparative Examples,
The processing machine used was LAY-724CB manufactured by Toshiba Corporation.

Table 1 shows the pattern formation state of the above Examples 1 to 5 and Comparative Examples 1 and 2.

[0024]

[Table 1]

[0025]

As is clear from the above table, the surface pattern of aluminum or its alloy obtained by the production method according to the present invention was a uniform pattern.

Claims (3)

(57) [Claims] 1. A porous anodic oxide film is formed on the surface of aluminum or an alloy thereof, and after coloring as required, a resin layer having high electrical insulation containing a black oil-soluble dye is formed on the surface,
After irradiating a YAG laser beam to remove the resin layer into an arbitrary shape, the porous anodic oxide film at the removed portion is removed and anodized again to form a porous anodic oxide film. A surface treatment method for aluminum or an alloy thereof, which is obtained by removing a resin layer after coloring and sealing the aluminum layer. 2. A porous anodic oxide film is formed on the surface of aluminum or its alloy, a resin layer having high electrical insulation containing a black oil-soluble dye is formed on the surface, and irradiated with YAG laser light. A surface treatment method for aluminum or an alloy thereof, which comprises removing the resin layer into an arbitrary shape, coloring the porous anodic oxide film in the removed portion, and then removing the resin layer and sealing. 3. A porous anodic oxide film is formed on the surface of aluminum or an alloy thereof, and after coloring, a resin layer having a high electrical insulation containing a black oil-soluble dye is formed on the surface to form a YAG laser beam. After irradiation to remove the resin layer into an arbitrary shape, the coloring material of the porous anodic oxide film is removed, and the porous anodic oxide film from which the coloring material has been removed is again colored with another coloring material. A method for surface-treating aluminum or an alloy thereof by removing and sealing.