Application of aluminum pigments in metallic inks

1. What is metallic ink?

Metallic ink refers to ink prepared with metallic pigments, which has a metallic luster. Generally speaking, gold ink and silver ink are this type of ink. The pigments of metallic inks are mainly gold powder and silver powder (copper gold powder and aluminum pigments). Other pigments can also be added to produce inks with special colors, which are called colored metallic inks. When the binder is acidic, the copper-gold powder reacts easily with trace amounts of sulfur and turns black; after printing, it reacts with sulfur in the atmosphere and slowly loses its luster. Therefore, gold ink can also use aluminum pigments and dyes to make pigments, but the gloss is slightly worse.

The binder of metal ink generally uses resin with extremely low acid value and amine value to avoid affecting the gloss of the ink, such as ethyl cellulose, nitrocellulose, polyvinyl acetate, ketone resin, polyphthalamine resin, and adding some wax substances to improve the suspension state of pigments. Metallic inks can also be formulated with solvents, but due to their low adhesion, they are often prepared and used immediately. The polarity of the solvent does not need to be too high, otherwise the pigment will easily precipitate due to excessive wetting. Xylene, isopropyl alcohol solvent, etc. can be used as solvents for metallic ink.

2. Application of aluminum pigments in metallic inks

The ink prepared using aluminum pigments is called metallic ink. As a new type of printing material, the emergence of metallic ink has expanded the creative space of packaging designers and opened up new ideas for the packaging industry. It is used in cigarette packages, wine labels, It is widely used in industrial packaging, food packaging, daily chemical product labels, flexible packaging, etc.