A brief introduction: oxide film dyeing and coloring of aluminum oxide plate

Dyed and colored anodized film is an important part of aluminum and its alloy anodized treatment, then by dyeing in the color and surrounding, the oxide film can show good color, as well as decorative film layer, corrosion resistance, light resistance and wear resistance will appear to varying degrees of increase.

The dyeing method of anodic oxide film can be divided into the following three categories.

1. Chemical immersion

The invention relates to a transparent anodic oxidation film based on sulfuric acid electrolysis, which comprises two dyeing methods of organic dye and inorganic pigment. The invention has the advantages of short process, simple process, easy to master, low production cost, diverse colors, bright colors, good decoration, etc. However, one of the disadvantages of immersion dyeing is that the surface of the pigment body is porous, so the color after immersion is not as light fast, light fast and wear resistant as the color obtained by other methods, especially the color of the organic dye.

Therefore, as an external decoration and the surface of the workpiece friction to regular, general decorative components used in the room, such as cosmetics bottles, brackets, lamps and other processing methods are not suitable.

2. Full coloring

The method is a method of obtaining chromophore while anodizing a color film, mainly using its own or its alloy electrolyte specific color development, or different power waves. The dye is present throughout the membrane wall, and the electrolyte can be an alloy or have light resistance, light resistance, and wear resistance properties, a residue that has been widely used in architectural decorative aluminum. The overall insufficient shade of color is a limitation, and the darker color bar, the cost of wastewater treatment is relatively high and difficult, and at present, the application is not common.

3. Electrolytic coloring process

The method after anodizing is based on the primary anodizing film of sulfuric acid, and then electrolytic coloring with alternating current in the solution containing metal salts, so it is also called secondary electrolytic coloring. When an electrochemical reaction occurs, the heavy metal ions entering the oxide film micropores are reduced to metal atoms and deposited in color on the barrier layer at the bottom of the pores. Because there are different kinds of heavy metal ions in various coloring solutions, the types of metals electrodeposited on the bottom barrier layer of the oxide film are also different, and the particle size and distribution uniformity are also different. Therefore, the selective absorption and scattering of various light waves exhibit different colors. Electrolytic coloring film has the advantages of good weather resistance, sun resistance, heat resistance, wear resistance, corrosion resistance, stable and durable color, and its energy consumption is much lower than the whole coloring film, so it is widely used in construction, mechanical and electrical, aviation, shipbuilding and national defense industries.