TWI401340B - Method of anodizing metal surface - Google Patents

Description

Metal surface anode treatment method

The invention relates to a metal surface anode treatment method, in particular to a multi-color anode treatment method which can be used for a curved surface.

Aluminum, titanium and alloy materials are widely used in aviation, electronics, communications and other fields due to their high strength and light weight. In order to further improve the surface quality and visual effect, the industry usually uses anodizing process or painting method to achieve. A method for decorating a titanium-based article is disclosed in U.S. Patent No. 5,215,606. First, prior to spraying the article, the substrate is first heated under vacuum to grow the surface of the substrate, then anodized, and the surface oxide layer is controlled by varying the voltage of the two electrodes. The color is obtained by the method, and the thickness of the oxide film is uniform, and the three-dimensional feeling of the convex and concave is lacking. The conventional anodizing process also has a method of obtaining an oxide film of different colors by using multiple anode treatments and multiple coloring. However, this method can obtain a multi-color oxide film on a metal surface, but each treatment can only be in the same plane. On the top, it is not possible to obtain a continuous three-dimensional color pattern on the curved surface at one time. The painting method has a simple pattern, a blurred outline and a weak adhesion of the paint film.

In view of the above, it is necessary to provide a metal surface anodizing method capable of obtaining a continuous three-dimensional color pattern on a curved surface.

A metal surface anode treatment method for treating aluminum, aluminum alloy and titanium alloy substrate surface, comprising the steps of: (1) anodizing the substrate to form a first oxide film on the surface of the substrate; (2) coloring the first oxide film; (3) spraying the ink on the substrate to completely shield the first oxide film on the surface; (4) attaching the film film having the desired pattern to the sprayed film (5) exposure treatment to cure ink that is not partially obscured by the pattern on the film film; (6) removal of uncured ink; (7) removal of the first oxide film not covered by the ink: (8) Performing a second anodizing treatment on the substrate to form a second oxide film on the surface of the substrate, the thickness of the first oxide film being different from the thickness of the second oxide film; (9) after the second anode treatment The second oxide film is subjected to a coloring treatment; (10) the remaining masking ink is removed; and (11) steps (3) to (10) are repeated.

Compared with the prior art, the method of the present invention precisely divides the film film having the desired pattern by vacuum pressing on the masking oxide film ink, by curing a part of the ink by first exposure, and then developing a part of the uncured ink. The area where re-anodic treatment is required to make the pattern finer and clearer. The film film used in the method can be used not only to be pressed against a certain plane of the metal substrate, but also to be deformed, so that it can also be pressed against the curved surface of the metal substrate, so that it can be used all at once in the metal substrate. The surface is obtained in a continuous and three-dimensional pattern. At the same time, the metal surface is obtained with a texture pattern having a high and low undulation by changing the conditions of each anode treatment.

The metal surface anodizing method of the preferred embodiment of the present invention is described by taking an anode surface treatment of a metal substrate as an example, and includes the following steps:

(1) cleaning the metal substrate with a solution containing the corresponding metal degreaser, then subjecting the metal substrate to a solution containing phosphoric acid and sulfuric acid for chemical polishing, followed by stripping the chemically polished metal substrate with a solution containing nitric acid The film is used to remove a black film formed on the surface of the workpiece due to the above chemical polishing treatment.

(2) The metal substrate is anodized to form an oxide film on the surface of the metal substrate. In this step, the anode treatment solution contains 180 to 200 g/L of sulfuric acid and less than 20 g/L of aluminum ions, and the treatment voltage is 11 to 13 V, and is treated at room temperature for 30 to 50 minutes.

(3) The metal substrate after the above anodization is subjected to adsorption coloring or chemical coloring treatment.

(4) The metal substrate after the coloring treatment is subjected to a sealing treatment to improve the anti-pollution and anti-corrosion properties of the surface oxide film.

(5) Spraying the ink on the metal substrate and completely shielding the surface oxide film. The ink is a photosensitive ink, and the thickness of the ink is 10 to 50 μm.

(6) A film film having a desired pattern is vacuum-applied to the metal substrate coated with the ink. In this step, a vacuum generator is used to form a vacuum between the film film and the metal substrate, and the film film is attached to the surface of the metal substrate under the vacuum suction force. The patterned portion of the film has been exposed to black, and the unpatterned portion is transparent.

(7) Exposure treatment to cure ink that is not partially obscured by the pattern on the film. The exposure processing step uses an astigmatism exposure machine with an exposure energy of 100 to 150 mj/cm ² and an exposure intensity of 5 to 25. The ink on the metal substrate that is not blocked by the pattern on the film film is cured by the film on the film. The pattern-blocking ink failed to cure.

(8) The vacuum state is released to disengage the film from the metal substrate, and the uncured ink is dissolved in a developing solution.

(9) Laser engraving or chemical etching to remove an oxide film that is not covered by ink. In this step, the chemical etching solution is a 60 ° C, 40 g / L sodium hydroxide solution, and the etching time is 10 to 60 seconds.

(10) A second anodizing treatment is performed on the chemical polishing and the metal substrate after the black film is peeled off, and the chemical polishing and blackening method is the same as described in the step (1).

(11) The oxide film obtained after the second anodizing treatment is subjected to adsorption coloring or chemical coloring treatment.

(12) The oxide film obtained after the second anodizing treatment is subjected to a sealing treatment.

(13) A mask having a clear outline and a strong stereoscopic effect can be obtained on the metal substrate by removing the remaining masking ink with a special stripping agent for the ink.

It can be understood that by repeating the above steps (5) to (12), a more color pattern can be obtained on the metal substrate.

It can be understood that the thickness of the oxide film obtained by each anode treatment can be made different by changing the conditions of each anode treatment such as the anode treatment time, so that a three-dimensional pattern having a high and low undulation can be obtained for the entire metal surface.

The method of the invention is suitable for surface treatment of metal substrates such as aluminum, aluminum alloys and titanium alloys. The method of the invention accurately presses the area which needs to be anodized again by vacuum-pressing the film film having the desired pattern onto the masking oxide film ink, curing a part of the ink by exposure, and developing the uncured part of the uncured ink. Make the pattern more precise and clear. The film film used in the method can be used not only to press on a certain plane of the metal substrate, but also to deform, and thus can also be pressed on the curved surface of the metal substrate, so that the entire surface of the metal substrate can be used at one time. The face is obtained in a continuous and three-dimensional pattern. At the same time, the metal surface is obtained with a texture pattern having a high and low undulation by changing the conditions of each anode treatment.

Claims (10)

A metal surface anode treatment method for treating aluminum, aluminum alloy and titanium alloy substrate surfaces, comprising the steps of: (1) anodizing the substrate to form a first oxide film on the surface of the substrate; (2) Coloring the first oxide film; (3) spraying the ink on the substrate to completely shield the first oxide film on the surface; (4) attaching the film film having the desired pattern to the ink-coated substrate (5) exposure treatment to cure ink that is not partially obscured by the pattern on the film film; (6) removing the uncured ink; (7) removing the first oxide film not covered by the ink; (8) the substrate Performing a second anodizing treatment to form a second oxide film on the surface of the substrate, the thickness of the first oxide film being different from the thickness of the second oxide film; (9) the second obtained after the second anode treatment The oxide film is subjected to a coloring treatment; (10) the remaining masking ink is removed; and (11) steps (3) to (10) are repeated. The metal surface anode treatment method according to claim 1, wherein the first or second anode treatment voltage is between 11 and 13 V, and the treatment time is 30 to 50 minutes. The metal surface anodizing method according to claim 1, wherein the coloring treatment is adsorption coloring or electrolytic coloring. The metal surface anodizing method according to claim 1, wherein the ink is a photosensitive ink. The metal surface anodizing method according to claim 1, wherein the exposure energy is 100 to 150 mj/cm ² and the exposure intensity is 5 to 25. The metal surface anodizing method according to claim 1, wherein the step (6) removes the uncured ink with a developing solution. The metal surface anodizing method according to claim 1, wherein the step (7) removes the first oxide film not covered by the ink by chemical etching. The metal surface anodizing method according to claim 1, wherein the step (10) removes the remaining masking ink by using a special stripping agent for ink. The metal surface anodizing method according to claim 1, wherein the surface chemical polishing and the blackening treatment are performed before each of the anodizing treatments. The metal surface anodizing method according to claim 1, wherein the oxide film is subjected to a sealing treatment after each coloring treatment.