JPS58216761A - Patterning and surface treatment of aluminum - Google Patents

Abstract

PURPOSE:To enable the formation of a pattern in free design, by using a resin curable by UV light, irradiating UV light thereto and forming the pattern on the anodized film of aluminum. CONSTITUTION:Aluminum 2 is first subjected to degreasing, cleaning, etching, etc. as a pretreatment and is electrolyzed in a bath which forms a porous oxide film such as of sulfuric acid or oxalic acid, so that an anodized film 7 is formed on the surface thereof. A paint 6a of a resin curable by UV light is beforehand stuck or printed by various methods on the anodized film and UV light is irradiated thereto from above the pattern to cure the pain 6a and the film 7 like a pattern in tight contact with each other. Since the paint 6a is cured quickly and is brought into tight contact with the film 7 when irradiated with the UV light, the efficiency in the surface treatment work is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a surface treatment method for producing a pattern on the surface of aluminum.

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

Traditionally used for building materials with complex cross-sectional shapes.

Various methods have been proposed for creating patterns on the surface of 77 reminium for various uses such as furniture, including immersing aluminum before anodizing in a certain liquid and treating it with electricity.

In this method, hydrogen gas generated on the surface of aluminum by current treatment forms an upward locus on the surface of the aluminum, and this locus forms a pattern. However, the generation of hydrogen gas during the energization process is not always constant,
Since it is extremely irregular, it is not possible to produce a uniformly regular pattern on the surface of aluminum, and it also has the disadvantage that the same pattern cannot be reproduced.

In addition, since the patterns produced by this method depend exclusively on the upward and downward trajectory of hydrogen gas, only monotonous line patterns or straight grain patterns can be obtained, making it difficult to create external designs suitable for various uses of aluminum. This has the disadvantage that a new pattern cannot be obtained at will.

On the other hand, when trying to generate a free design pattern, there is nothing better than a general printing method, but it has a problem that it cannot be applied to aluminum, which has a complicated cross-sectional shape.

Therefore, the present invention has developed a pattern-creating surface treatment method that can generate not only monotonous line patterns but also free design patterns similar to printing methods, even on aluminum for building materials, which has a complex cross-sectional shape. With the aim of providing this product, we have devised our own ingenuity, using ultraviolet curable resin, which is cured by irradiating it with ultraviolet rays, and based on the difference between the cured part and the other parts. It is designed to generate colored patterns.

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

First, an anodic oxide film is generated on the surface of the aluminum, but in order to generate this, it is pretreated by conventional methods such as degreasing, cleaning, etching, and removal of Sumano 1. Direct current electrolysis, alternating current electrolysis or alternating current electrolysis or alternating current electrolysis in a bath that produces a porous oxide film.

Electrolytic treatment is performed using other current waveforms that have the same effect. Although a normal anodic oxide film does not develop color, it may be colored during formation of this anodic oxide film.

In addition, a non-colored anodic oxide film that does not develop color can be made into a colored film by performing the following treatment.

In a coloring bath mainly composed of acids or salts of various metals involved in coloring, such as fll nickel, copper) Lt l, M, s, manganese, etc., appropriate current waveforms such as AC electrolysis, DC cathode electrolysis, or AC/DC superimposed electrolysis are applied. A method of applying electrolytic coloring using.

(2) A bath mainly composed of one or more inorganic acids selected from orthophosphoric acid, pyrophosphoric acid, sulfurous acid, chromic acid, sulfuric acid amide, high concentration sulfuric acid of 40 V/v% or more, or salts thereof; 10H group or -COOH such as malic acid, maleic acid, citric acid, tartaric acid, sulfosalicylic acid, gallic acid, etc.
The anodic oxide film of aluminum is immersed in a bath mainly containing one or more of various organic acids or salts thereof, or an appropriate mixture of these baths, and then subjected to direct current,
After changing the micropore structure of the anodic oxide film by applying current using alternating current, a waveform in which positive and negative polarities are alternately changed, or an AC/DC superimposed waveform, (1)
A method of electrolytic coloring in a coloring bath.

(3) A method of coloring by dipping in dye.

As mentioned above, the colored (including coloring) anodic oxide film,
Alternatively, an ultraviolet curable resin paint is applied to the uncolored anodic oxide film. It consists of a prepolymer as the main ingredient, a photopolymerization initiator that absorbs the outer rays of the thin leaves and starts the polymerization reaction, a photopolymerizable monomer as a diluent, and various additives such as pigments.

Then, as a means of depositing this ultraviolet curable resin paint on the surface of the anodic oxide film, it is possible to apply it directly to the surface.
Of course, various printing methods such as screen printing and offset printing can be used. but,
The following method is particularly effective for aluminum that has a complicated uneven surface.

It consists of a water-soluble thin film such as polyvinyl alcohol printed with ultraviolet curable resin paint, and then floated on the surface of the liquid with the printed surface bent upwards, and then immersed in the liquid while pressing aluminum against the printed surface. By submerging the aluminum, we use hydraulic pressure to adhere the thin film to the entire surface of the aluminum.
This is a method of attaching the ultraviolet curable resin coating on the printing surface to the aluminum surface.

In this method, after the ultraviolet curable resin coating is applied, the thin film is removed using an appropriate method such as hot water washing.

In addition, the material of the thin film is polyvinyl alcohol,
Synthetic polymers include polyacrylic acid sorta, polyvinylpyrrolidone, polyethylene oxide, methyl cellulose, carboxymethyl cellulose, acrylamide, etc., and animal polymers include glue, gelatin, casein, polypeptide, etc. Examples of vegetable polymers include starch, cellulose, dextrin, and soy protein.

In this way, the UV-curable resin paint adhered to the aluminum anodic oxide film is irradiated with ultraviolet rays to harden it in a pattern.One way to harden the paint in a pattern is to directly coat the aluminum After adhering to the surface in a pattern, or by printing a pattern on a thin film in advance,
After applying this thin film to the aluminum surface in a pattern using hydraulic pressure as described above,
This is done by irradiating this patterned ultraviolet-curable resin coating with ultraviolet light.

By this irradiation, the ultraviolet curable resin paint is cured while being in close contact with the anodic oxide film, forming a patterned paint layer.

In addition, as another means of closely curing the ultraviolet curable resin paint in a pattern, after uniformly depositing it on the entire surface of the aluminum using the above-mentioned adhesion means, the method shown in Fig. 1 is used to apply ultraviolet rays. As shown, the ultraviolet source (1
) and aluminum (2) with an appropriately patterned transparent part (
The transparent part (3) is interposed by the shielding body (4) formed with the transparent part (3).
), and by curing the resin paint (6) according to the shape of the transparent part (3), a patterned paint film (6a) in close contact with the positive (j oxide film) is created.
).

In this means, the shielding body (4) consists of an ultraviolet transmitting part (3) and an ultraviolet absorbing part (5), and the ultraviolet transmitting part (3) has a content i of iron oxide contained as an impurity of 0.
The ultraviolet absorption part (5) is made of glass with an iron oxide content of about 1%, and the absorbency is increased by adding cerium ions. can be increased. Other effective substances that increase this ultraviolet absorption include quartz, potassium chloride, silica, and lithium fluoride.

In addition, the portions that remain uncured due to the ultraviolet rays being blocked by the shielding body (4) are removed by spraying an appropriate removal liquid such as water, and the anodic oxide film is adhered and hardened in a pattern. Only the resin coating layer left behind (Figure 2).

Note that (7) in the figure represents a colored film.

In each of the above methods, if the anodic oxide film is in a non-colored state, various pigments may be added to the ultraviolet curable resin paint, or if the anodic oxide film is colored or developed, these methods may be applied. By adding a pigment with a different color tone to the resin paint, it is possible to create a vivid colored pattern.

The above contents can be summarized as follows.

(1) After applying a pigment-added ultraviolet curable resin paint to a non-colored anodic oxide film in a pattern, UV rays are irradiated to form a patterned coating layer.

(2) After applying UV-curable resin paint containing pigments to the entire surface of the uncolored anodic oxide film, UV rays are irradiated through a shielding plate that has UV-transmitting areas, and a pattern is created depending on the UV-transmitting areas. Forms a hardened coating layer.

('5) After applying a pigment-added ultraviolet curable resin paint to the colored or developed anodic oxide film in a pattern, UV rays are irradiated to form a patterned coating layer.

(4) After applying a pigment-added ultraviolet curable resin paint to the colored or developed anodic oxide film, UV rays are irradiated through a shielding grate that has an ultraviolet transmitting area, and a pattern is created depending on the transmitting area. Forms a hardened coating layer.

By repeating these methods, as shown in FIG. 6, a further cured ultraviolet curable resin coating layer is superimposed on the pattern-cured ultraviolet curable resin coating layer.
A three-dimensional uneven pattern can be formed.

Furthermore, in the present invention, after the ultraviolet ray curable resin coating is irradiated with ultraviolet rays, it can be further subjected to an electrolytic coloring treatment. This electrolytic coloring treatment is carried out by applying an electric current in the electrolytic coloring bath described above, but since the converted ultraviolet curable resin coating layer does not conduct electricity, the portion where the coating layer exists is electrolytically colored. Rather, a colored pattern of varying shades or different tones is created between this portion of the coating layer that has not been electrolytically colored and the other portions of the anodic oxide film that have been electrolytically colored.

In this case, the anodic oxide film to which the ultraviolet curable resin paint is attached has been treated as described below.

(al) Uncolored or colored state by the above-mentioned anodic oxidation treatment.

[1) l The anodic oxide film in the non-colored state is
A bath mainly containing one or more inorganic acids among J-acid, pyrophosphoric acid, sulfuric acid, chromic acid, sulfuric acid amide, high concentration sulfuric acid of 40V/V% or more or their salts, malic acid ,
Baths mainly containing one or more of various organic acids containing 10H or -COOH groups, such as maleic acid, phosphoric acid, sulfosalicylic acid, gallic acid, or their salts, or their salts. A state in which the micropore structure of the anodic oxide film is changed by being immersed in a suitably mixed bath and subjected to electrical treatment.

A state in which an anodic oxide film is electrolytically treated to form a colored film in a coloring solution containing acids or salts of various metals involved in coloring, such as nickel, cobalt, copper, tin, and manganese.

After changing the micropore structure of the anodic oxide film using the method described in Idl + b), electrolytic coloring treatment is performed using the method described in 1c) above, and the state is colored to a color tone different from that obtained by the method described in Cl.

Transparent ultraviolet curable resin paint with or without pigments is applied to these anodic oxide films in various states, and the method of adhesion is the same as described above, and the pattern is created by irradiating ultraviolet rays. The means for closely curing the material is also as described above.

After this, an electrolytic coloring process is performed, and the color tone resulting from this electrolytic coloring process, whether or not pigments are added to the UV-curable resin paint, and the coloring (color development) of the anodic oxide film before the UV-curable resin paint is attached are determined. Various color combinations are possible depending on whether the

Taking this point into consideration, the processing steps are summarized as follows.

(a) A transparent ultraviolet curable resin paint is attached to the anodic oxide film (non-colored), a patterned coating layer is formed by ultraviolet irradiation, and then electrolytic coloring is performed.

At this time, the non-colored anodic oxide film remains on the coating layer forming area, and the other areas are colored.

fcffl An ultraviolet curable resin paint containing pigments is applied to the anodic oxide film (non-color forming), and after UV irradiation forms a patterned coating layer, electrolytic coloring treatment is performed.

At this time, a colored pattern is formed by the paint layer containing the pigment and other electrolytically colored parts.

(c) A transparent (or pigment-containing) ultraviolet curable resin paint is attached to an anodic oxide film (non-colored) with a change in the micropore structure, and a patterned coating layer is formed by UV irradiation. Afterwards, do electrolytic coloring. In this case, the areas other than the areas where the coating film layer is formed have a color tone different from that obtained by normal coloring treatment.

(2) After the first electrolytic coloring treatment is applied to the anodic oxide film (non-colored) in a coloring bath containing various metal salts or acids as the main components, a transparent ultraviolet curable resin paint is applied. A patterned coating layer is formed by irradiation with ultraviolet rays, and then a second electrolytic coloring treatment is performed. In this case, the second electrolytic coloring effect does not reach the part where the coating layer is formed, and the color tone from the first electrolytic coloring is maintained, and the other parts are due to the first and second electrolytic coloring. It becomes a complex color tone.

(e) The anodic oxide film (non-colored) with a change in the micropore structure is subjected to the first electrolytic coloring treatment shown in (a) above to give it a different color tone from the normal coloring treatment, and then it becomes transparent. A UV curable resin paint is applied and a patterned coating layer is formed by irradiation with UV rays. Perform a secondary electrolytic coloring treatment. In this case, the effect of the secondary electrolytic coloring treatment does not reach the area where the coating layer is formed, and the color tone from the primary electrolytic coloring treatment is maintained, while other areas retain the color tone of the primary and secondary electrolytic coloring treatments. It becomes a complex tone due to coloring.

As described above, the present invention skillfully utilizes the characteristics of an ultraviolet curable resin paint when forming a pattern, and the paint is cured in a short time by irradiation with ultraviolet rays.
Since it is in close contact with the anodic oxide film, the time required for pattern formation can be shortened and the efficiency of surface treatment work can be improved.

Examples of the method of the present invention are shown below.

[Example 1] After degreasing and cleaning an aluminum plate A1200p in a 10W 1% nitric acid bath, it was etched by immersing it in a 5Wf% sulfur/IJium hydroxide bath for 8 minutes at a bath temperature of 50°C, and then etched in a 10W 1% nitric acid bath.
Sumano 1-removal was carried out in a 0Wj1 nitric acid bath. This aluminum plate was placed in a 15W/% sulfuric acid bath at a bath temperature of 20°C and an electric sound of 1. Anodic oxidation treatment was performed for 30 minutes under OA/dIA conditions. After drying this aluminum alloy, its surface is coated with orange ink (
Daicure UV ink SSK type manufactured by Dainippon Ink)
A thin film made of polyvinyl alcohol screen-printed with a floral pattern was brought into close contact with the film using hydraulic pressure, and an ultraviolet-curable resin paint with a floral pattern was attached. After dissolving and removing only the thin film of the aluminum alloy in this state with hot water at °C, irradiation with ultraviolet rays for 1 second from a high-pressure mercury lamp (output 2 KW) resulted in an orange floral pattern that adhered and hardened on the silver anodic oxide film. A coating layer was formed.

[Example 2] After subjecting an aluminum plate A I 200 P to the same pretreatment and anodic oxide film forming treatment as in Example 1, it was heated in a ferric ammonium oxalate 1o I/e bath at a bath temperature of 70°C. By incubating for 2 minutes under these conditions, a pale golden dyed film was produced.

After drying this aluminum plate, black ink consisting of ultraviolet curable resin paint (Daicure U manufactured by Dainippon Ink) was applied.
After applying and adhering V ink (SSK type) to the entire surface, a shielding plate with a polka dot-shaped ultraviolet transmitting area is interposed between the aluminum plate and a high-pressure mercury lamp, and ultraviolet rays are irradiated for one second. The hardening resin paint hardened into a polka dot pattern and adhered closely to the anodic oxide film.

Next, when the uncured ultraviolet curable resin paint was washed off with a jet shower, a black polka dot pattern coating layer was formed on the pale golden anodic oxide film.

[Example 6] After subjecting an aluminum plate A I 200 P to the same pretreatment and anodic oxide film forming treatment as in Example 1, it was connected to an anode in this aluminum alloy and heated to a bath temperature of 20°C, D, and C. , IOV for 3 minutes to cause structural changes in the micropores of the anodic oxide film.

This aluminum plate was treated with 15 f/e of stannous sulfate.

A wine red primary colored film was produced by electrolytic treatment for 1 minute in a bath of sulfuric acid 10117e and sulfosalicylic acid 10y/e at a bath temperature of 20°C, A, C, and 23V.

Next, after drying this aluminum plate, a thin film made of Dengun with a floral pattern gravure printed using yellow ink made of ultraviolet curable resin paint (Daicure UV Ink SSK type manufactured by Dainippon Ink) was applied to By applying pressure to the surface of the aluminum plate, an ultraviolet curable resin paint with a floral pattern was adhered to the surface of the aluminum plate.

After dissolving and removing the thin film from the aluminum plate in this state with hot water at 40°C, irradiation with ultraviolet rays for 2 seconds using a high-pressure mercury lamp produces a yellow floral pattern that adheres to and hardens on the wine red anodic oxide film. A coating layer was formed.

[Example 4] Aluminum alloy A6063S was subjected to the same pretreatment and anodic oxidation treatment as in Example 1 and dried, and then a wood grain pattern was applied using an ultraviolet curable resin paint (Super Regis FSR manufactured by Fuji Yakuhin ■). A thin polyethylene oxide film screen-printed on the surface of the aluminum alloy was brought into close contact with the surface of the aluminum alloy using hydraulic pressure, thereby depositing 41 UV-curable resin paints in a wood grain pattern on the surface of the aluminum alloy.

After removing the thin film from the aluminum alloy in this state using 40℃ hot water, irradiating it with ultraviolet rays for 2 seconds using a high-pressure mercury lamp, the transparent acid-resistant film adhered to the silver anodic oxide film and hardened in a wood grain pattern. A transparent and non-conductive coating layer was formed.

Next, this aluminum alloy was treated with sulfuric acid disulfide/l15o
f/11. When connected to the cathode in a boric acid "3o 1//e (') coloring bath and subjected to electrolytic treatment for 2 minutes at a bath temperature of 20°C, D, C, and 25V, the parts other than the coating layer will be colored bronze. A wood grain-like colored pattern of bronze and silver was formed.

[Example 5] The same 111 as in Example 1 was added to aluminum alloy A6063S.
After treatment and anodic oxide film formation treatment, 1, connect to the anode in a bath of 100 f/l phosphorous acid, bath temperature 20 ° C.
Structural changes were made to the micropores of the anodic oxide film by electrolytic treatment under the conditions of D, C, 10V, and treatment time of 4 minutes.

After drying this aluminum alloy, a polyvinyl alcohol thin film with a wood grain pattern gravure printed using ultraviolet curable resin paint (TPR manufactured by Tokyo Ohka Kogyo ■) was applied.
By applying hydraulic pressure to the surface of the aluminum alloy, the wood grain-like UV-curable resin paint was adhered to the surface of the aluminum alloy. After dissolving and removing the thin film from the aluminum alloy in this state using 40°C hot water, it is irradiated with ultraviolet rays for 2 seconds using a high-pressure mercury lamp, and it adheres to the silver anodic oxide film and hardens into a wood grain pattern. A transparent, acid-resistant, non-conductive coating layer was formed.

Next, this aluminum alloy was mixed with 15 g of stannous sulfate/(
1', sulfuric acid 10. f/(1, sulfosalicylic acid 10
In a coloring bath containing f/e, bath Fa 20°C, A, C, 2
When electrolytically treated under the conditions of 0 V and 3 minutes, the parts other than the coating layer were colored green, and a wood grain-like colored pattern of silver and green was formed.

[Example 6] Aluminum alloy A6063S, which had been subjected to the same pretreatment and anodic oxide film formation treatment as in Example 1, was treated with 100% of stannous sulfate.
f/11, 10 f/e of sulfuric acid, and 10 g/e of sulfosalicylic acid at a bath temperature of 20 tl:,A,
An amber colored film was obtained by electrolytic treatment under the conditions of c, 1 sV, and 2 minutes.

After drying this aluminum alloy, a polyvinyl alcohol a thin film gravure printed in a wood grain pattern using a transparent ultraviolet curable resin paint (Super Resist FSR manufactured by Fuji Yakuhin) is applied to the surface of the aluminum alloy using hydraulic pressure. The ultraviolet curable resin paint was adhered to the aluminum surface.

After dissolving and removing the thin film from the aluminum alloy in this state using hot water at 40°C, irradiation with ultraviolet rays for 2 seconds from a high-pressure mercury lamp causes the amber colored film to adhere and harden to become transparent and acid-resistant. In addition, a non-conductive wood-grain coating layer was formed.

Next, this aluminum alloy was electrolytically treated in the same coloring bath as above at A, C, 20V, treatment time 8 minutes, and the parts other than the coating layer were electrolytically colored and turned black, leaving amber color and plaque. A wood grain-like colored pattern was formed.

[Example 7] Aluminum alloy A6063S subjected to pretreatment and anodic oxide film formation treatment in the same manner as in Example 1, phosphorous acid 100
Connected to the anode in a bath of f/e, bath temperature 25℃, D, C
, 20V and a treatment time of 2 minutes, structural changes were made to the micropores of the anodic oxide film.

After this, the aluminum alloy was treated with manganese sulfate 20 f/
e, Hydrogen peroxide solution 20 wl/e (1) Connected to the cathode in a bath and electrolytically treated under the conditions of bath temperature 20℃, D, C, 30V, treatment time 30 seconds, a pale golden color. It was made into an Ω colored film.

Next, transparent ultraviolet curable resin paint (Dainippon Ink ■
A thin film made of polyvinyl alcohol offset-printed in a wood grain pattern is adhered to the aluminum alloy using hydraulic pressure using an acid-resistant and alkali-resistant resist inn ('tUVPR) produced by the Company. A resin paint was applied.

After removing the thin film from the aluminum alloy in this state using 40°C hot water, it was exposed to ultraviolet light for 1 second using a high-pressure mercury lamp, and a transparent, non-conductive layer was formed by adhering to the pale golden colored film and hardening it. A wood grain-like coating layer was formed.

Next, this aluminum alloy was connected to the cathode in the same coloring bath as above, and when electrolytically treated at C, 45V, and for 2 minutes, the parts other than the coating layer were electrolytically colored and became yellow ocher. A wood grain pattern was formed by this ocher color and pale golden color.

After that, soak it in UV ink remover made by Dainippon Ink.
The ultraviolet curable resin coating layer was removed by soaking for a minute.

[Brief explanation of the drawing]

FIG. 1 is a diagram of ultraviolet irradiation using an agIli plate, and FIGS. 2 and 3 are cross-sectional views of aluminum having a coating layer. Continued from page 1 0 Inventor Mitsuo Sakashita Inside Sankyo Aluminum Industry Co., Ltd., 70 Hayayo, Takaoka City

Claims (1)

[Scope of Claims] (1) An ultraviolet curable resin coating layer adhered to an anodic oxide film of aluminum. Aluminum patterning is a surface treatment method. (2) A surface treatment method for patterning aluminum according to claim 1, which uses an anodic oxide film of aluminum in a non-colored state and an ultraviolet curable resin paint added with a pigment. (6) A surface treatment method for patterning aluminum according to claim 1, which uses a colored anodic oxide film of aluminum and an ultraviolet curable resin paint to which a pigment of a different color tone is added. (4) After irradiating the UV-curable resin coating adhered to the anodic oxide film of aluminum with ultraviolet rays to form a UV-curable resin coating layer that is hardened in a pattern on the anodic oxide film, this aluminum is Aluminum patterning is a surface treatment method characterized by electrolytic coloring to form colored patterns with different tones between the ultraviolet curable resin coating layer and other parts. (5) Aluminum pattern A; 1-piece surface treatment method according to claim 4, which uses an anodic oxide film of aluminum in a non-colored state. (6) The aluminum pattern example described in claim 4 is a surface treatment method that uses a pre-colored anodic oxide film of aluminum and a transparent ultraviolet curable resin paint.