Choosing Dyes for Aluminum Oxidation Equipment

1. Choosing Dyes for Aluminum Anodizing Equipment

There are many types of organic dyes, and the choice depends on different applications and product grades. Soluble reactive dyes are expensive but have excellent colorfastness, so they are mostly used for coloring high-end aluminum products like pens, lighters, and hearing aids. Alcohol-soluble dyes are used for aluminum foil coloring, while oil-soluble dyes are used for aluminum foil printing. Before use, oil-soluble dyes are dissolved in lacquers based on nitrocellulose, ethylene resin, or polyamide resin, or in baking paints with melamine resin and epoxy resin, and after printing on cleaned aluminum foil, they form a resin film containing the dye. The types of dyes used for coloring aluminum products include acid dyes, acid complex dyes, acid mordant dyes, direct dyes, weak acid dyes, disperse dyes, soluble reactive dyes, reactive dyes, basic dyes, alcohol-soluble dyes, and oil-soluble dyes.

2. Anodized Aluminum Equipment Organic Dye Coloring Process and Control

Single-color dyeing: After anodizing aluminum products and rinsing them with clean water, immerse them in the dye bath at the specified temperature. The dyeing time depends on the color depth, and the bath volume can be controlled at a 10:1 ratio relative to the volume of the products.

Multi-color dyeing: If dyeing aluminum parts with two or more different colors, such as landscapes, flowers and birds, patterns, or text, printing techniques are usually used. Printing plates can be relief plates (zinc or paper) or silk screens, and methods may include direct printing, resist coating, or foam stamping. Generally, the process is to dye the first color, then apply a protective lacquer to the areas that should retain that color, remove the remaining color, and repeat for the second, third, and additional colors as needed.