JPS5847474B2 - How to color aluminum or aluminum alloy - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for coloring aluminum or an aluminum alloy (hereinafter both are simply referred to as aluminum or treated material), and its purpose is to color aluminum after forming an anodized ammonium film. The object of the present invention is to establish a novel method for coloring aluminum, which allows a colored film in two or more different tones to be obtained on the surface of an object to be treated by electrolytic treatment.

In general, when anodized aluminum is electrolytically colored using a counter electrode using a normal coloring method, that is, alternating current, direct current (cathode), AC/DC superimposition, or a waveform current that has an equivalent effect, It is well known that various colored films can be formed on the surface of a treated object depending on the type of metal salt or acid contained in the electrolyte.

In the electrolytic coloring process described above, a colored film with a uniform color tone can always be obtained as long as the bath management of the electrolytic solution and the electrolytic conditions such as electrolytic voltage, electrolytic time, and current density are not set incorrectly.

In the above-mentioned coloring method, the method of the present invention is to color aluminum that has been anodized in advance using an aqueous solution containing a metal salt or an acid as an electrolytic coloring bath. This method is characterized in that an auxiliary electrode made of a conductive material having the same polarity as the object to be treated is installed to perform the electrolytic coloring treatment.

When such an electrolytic coloring treatment is performed, in the electrolytic treatment process in a coloring bath with a conductive material as an auxiliary electrode, current flows through the conductive material with the same polarity as aluminum, and the treated material near the auxiliary electrode A current distribution θ difference occurs between the surface of the object and the surface of the object far from the auxiliary electrode, and as a result, the color tone of the aluminum after coloring has a difference in shading (including coloring before and after coloring), and the color tone changes. A colored film with different and uneven coloring is obtained.

Then, after this coloring unevenness generation step, a normal electrolytic coloring treatment or immersion coloring treatment is performed without using an auxiliary electrode, or, prior to the coloring unevenness generation step, the aluminum surface is subjected to a normal electrolytic coloring treatment. By applying a different color, it is possible to obtain a colored film that is divided into two or more different colors, as well as differences in tone.

The method for coloring aluminum according to the present invention is based on the above-mentioned coloring principle, and to supplementarily explain the points to be kept in mind when carrying out the method, the coloring bath may be a normal electrolytic coloring bath, such as Co, Ni, etc. , Fe) Cu)
The current waveform used for electrolytic coloring treatment is direct current (cathode), alternating current, superimposed alternating current, or equivalent effect. Anything shown is possible.

In addition, carbon, stainless steel, nickel, iron, copper, aluminum, titanium, etc. are commonly used as conductive substances that serve as auxiliary electrodes, and the closer the conductive substance is to the object to be treated, the stronger the coloring will be, and the darker the color will be. (It may be in contact with the object to be processed), and vice versa if it is far away.

If the shape of the conductive material is linear, the uneven coloring will become thin, and if the shape of the conductive material is plate-like, it will appear as a band-like light-colored area. When the color is close to that of the original, light-colored areas appear and the contrast between light and shade becomes clearer.

Next, specific examples of the coloring method according to the present invention will be described.

Example 1 After applying an anodic oxide film of approximately 10 microns to an aluminum alloy plate (60638) by sulfuric acid electrolysis, the following conditions were applied to the uneven coloring: selenium dioxide 15g/l) zinc sulfate 0.3g/IJ copper sulfate 1 j9# Counter electrode (anode) Carbon conductive material (cathode) Carbon plate heated At room temperature, sample 1, counter electrodes 2, 2, and auxiliary electrode 3 are placed in the relative positions shown in Figure 2, and from sample 1 to auxiliary electrode 3 to about 2c
The above sample and auxiliary electrode are placed on the cathode with a distance of 1 m, and a direct current of 1
When electrolyzed at 4 V for 2 minutes, a patterned colored film was obtained, which was colorless on the conductive material side (auxiliary electrode side) and cold on the opposite side.

Example 2 After applying an anodized film of approximately 10 microns to an aluminum alloy plate (6063S) by sulfuric acid electrolysis, electrolytic coloring was performed under the same conditions as Example 1, and the conductive material side was colorless and the opposite side was colored with a gold pattern. After obtaining the film, use a colored liquid with the following conditions: Selenium dioxide 159/1 Zinc sulfate 0.3'?/1 Copper sulfate 1 g/1 Counter electrode (anode) Carbon temperature change Room temperature When electrolyzed at 15 V DC for 1 minute, a colored pattern consisting of gold shading was obtained.

Example 3 An aluminum plate (99.2%) was coated with about 7
After applying a micron anodic oxide film, the sample was colored unevenly using the following conditions: nickel sulfate 50 g/1 boric acid 40 g/1 counter electrode (anode) nickel conductive material (cathode) nickel wire temperature room temperature 1, counter electrodes 2 and 2, and auxiliary electrode 3 are placed in the relative positions shown in FIG.
The above sample and auxiliary electrode are placed on the cathode with a distance of 1 m, and a direct current of 1
When electrolyzed at 8V for 40 seconds, a conductive material (auxiliary electrode)
A colored film with a bronze pattern was obtained in the other parts.

This is further colored with the following conditions: selenium dioxide 15El/l) zinc sulfate 0.3g/1 copper sulfate 1g/l! When the carbon temperature of the counter electrode (anode) was set to room temperature and the sample was placed on the cathode and electrolyzed at 15 V DC for 2 minutes, a colored pattern consisting of two colors of bronze and gold was obtained.

Example 4 After applying an anodic oxide film of about 10 microns to an aluminum alloy plate (60638) by sulfuric acid electrolysis, uneven coloring was applied under the following conditions using a coloring solution of nickel sulfate 5o9/l! boric acid
409/1 Counter electrode (anode → nickel conductive material (cathode) Nickel wire (leave 3 mm in the center, the rest is electrically insulated) Temperature Using room temperature, test sample 1, counter electrodes 2 and 2, and auxiliary electrode 3, respectively. The auxiliary electrode 3 is placed at the relative position shown in FIG.
V. When electrolyzed for 40 seconds, the central part of the sample was colorless in a circular shape, and the rest of the sample was colored in a bronze pattern.

This was further colored with the following conditions: Selenium dioxide 8E//1 Copper sulfate 1g'/1 Zinc sulfate 0.5g/1 Counter electrode (anode) Carbon temperature change Using room temperature, placing the sample on the cathode and applying DC 12V. When electrolyzed for 2 minutes, a patterned colored film consisting of two colors, brown and gold, was obtained.

Example 5 After applying an anodic oxide film of approximately 12 microns to an aluminum alloy plate (60638) by sulfuric acid electrolysis method, uneven coloring was applied under the following conditions: nickel sulfate 509/1 boric acid 4 og/IJ counter electrode nickel conductive material (sample (same polarity) Stainless steel plate temperature change
Using room temperature, sample 1, counter electrodes 2, 2, and auxiliary electrode 3 are placed in the relative positions shown in Figure 1, and the auxiliary electrode 3 is approximately 5
When the CTL was separated and electrolysis was performed at 20 V AC for 1 minute, the surface facing the conductive substance (auxiliary electrode) was colorless, and the opposite surface had a bronze pattern.

This is further colored with the following conditions: Selenium dioxide 10g/l Zinc sulfate 0.3g/IJ Copper sulfate 0.5g/1 Counter electrode (anode) Carbon temperature Use room temperature, place the sample on the cathode, DC 15V, 2 When electrolyzed for a minute, a patterned colored film consisting of two colors, bronze and gold, was obtained.

Example 6 After applying an anodic oxide film of approximately 12 microns to an aluminum alloy plate (6063S) by sulfuric acid electrolysis method, uneven coloring was applied to the aluminum alloy plate (6063S) using a coloring solution of selenium oxide 8 g# zinc sulfate 0.37i/13 copper sulfate
0.5g/IJ counter electrode (anode)
Carbon conductive material (cathode) Using a carbon rod at room temperature, sample 1, counter electrodes 2, 2, and auxiliary electrode 3 were placed in the relative positions shown in Figure 2, and auxiliary electrode 3 was separated from sample 1 by about 5 steps. Then, the above sample and the auxiliary electrode were placed on the cathode, and a direct current of 12
V, when electrolyzed for 2 minutes, the conductive material side at the end of the sample (
A patterned colored film was obtained in which the auxiliary electrode side) was colorless and the rest was gold.

This was further mixed with a colored solution under the following conditions: nickel sulfate 50 g/1 boric acid 40 g/1 counter electrode (anode) nickel temperature change using room temperature, placing the sample on the cathode and electrolyzing at 15 V DC for 40 seconds. A gold-patterned colored film with a bronze border on one edge was obtained.

Example 7 After applying an anodic oxide film of about 10 microns to an aluminum alloy plate (6063S) by sulfuric acid electrolysis method, coloring liquid selenium dioxide 159/1 copper sulfate 0.59/11 zinc sulfate 0.39/ 1. Counter electrode (anode) Using a carbon temperature of room temperature, a sample was placed on the cathode and electrolyzed at 11 V DC for 2 minutes, and a uniform gold colored film was obtained.

This is further colored unevenly under the following conditions: Coloring liquid Nickel sulfate 509/l Boric acid 40g/1 Counter electrode (anode) Nickel conductive material (cathode) Nickel plate temperature Using room temperature, sample 1, counter electrodes 2 and 2, and auxiliary electrode 3 are mixed. The auxiliary electrodes 3 from the sample 1 are placed at the relative positions shown in FIG.
Place the sample and the auxiliary electrode on the cathode and apply a direct current of 1
When electrolyzed at 4V for 2 minutes, the conductive material side was cold, and the opposite side had a bronze-patterned colored film.

Example 8 After applying an anodized film of approximately 12 microns to an aluminum alloy plate (6063S) by sulfuric acid electrolysis, uneven coloring was applied to the aluminum alloy plate (6063S) using a coloring solution of nickel sulfate 50 g/11 boric acid under the following conditions.
40g/l! Counter electrode (anode) Nickel conductive material (cathode) Titanium plate temperature Using room temperature, sample 1, counter electrodes 2, 2, and auxiliary electrode 3 are placed in the relative positions shown in Figure 1, and the auxiliary electrode 3 is separated from sample 1 by approx. IC
IIL was separated, the sample and the auxiliary electrode were placed on the cathode, and electrolysis was carried out at 20 V DC for 20 seconds. As a result, a colored film with a colorless pattern on the surface facing the conductive substance and a bronze pattern on the back side was obtained.

Subsequently, this was immersed in a 10 g/l ferric ammonium oxalate solution at 50° C. for 10 minutes, resulting in a colored film with a pattern of bronze on one side and gold on the opposite side.

[Brief explanation of the drawing]

FIGS. 1 and 2 are flat diagrams showing the relative positions of a sample, a counter electrode, and an auxiliary electrode during electrolytic coloring treatment in a colored solution, respectively. 1...Sample, 2...Counter electrode, 3...
...Auxiliary pole.

Claims (1)

[Claims] 1. When coloring aluminum or aluminum alloy that has been anodized in advance using an electrolytic coloring bath using an aqueous solution containing a metal salt or acid, the coloring bath contains a counter electrode and an object to be treated. A method for coloring aluminum or aluminum alloy, in which an auxiliary electrode made of a conductive material of the same polarity is installed and an electrolytic coloring treatment is performed to obtain a colored film in two or more different tones on the surface of a treated object. 2. When coloring aluminum or aluminum alloy that has been anodized in advance using an aqueous solution containing a metal salt or acid as an electrolytic coloring bath, first, in addition to the counter electrode, conductive electrodes of the same polarity as the object to be treated are added to the coloring bath. An auxiliary electrode made of a substance is installed and an electrolytic coloring process is performed, and then a normal electrolytic coloring process or an immersion coloring process is performed without using an auxiliary electrode to coat the surface of the object to be treated.
A method for coloring aluminum or aluminum alloy to obtain a colored film that is divided into more than one different color tone. 3. When coloring pre-anodized aluminum or aluminum alloy using an aqueous solution containing a metal salt or acid as an electrolytic coloring bath, first perform the usual electrolytic coloring treatment as the primary coloring, and then electrolyze as the secondary coloring. In addition to the counter electrode, an auxiliary electrode made of the same conductive material as the object to be treated is installed in the coloring bath to perform electrolytic coloring treatment, and two or more types of
A method for coloring aluminum or aluminum alloys to obtain colored films with different tones.