Clarifications of aluminium pigments
Clarifications of aluminium pigments
Have you know about the classification of aluminum pigments? Aluminum pigment is one of the special powders, also known as aluminum powder pigment, aluminum silver powder, aluminum silver paste. Aluminum pigments are flake powders. Compared with other pigments, they have unique properties such as covering power and metallic brillance effects. They are widely used in anti-corrosion coatings, automotive coatings, architectural coatings and printing inks. Today we briefly introduce the classification of aluminum pigments.
1. According to surface modifiers
Aluminum pigments are divided into four categories according to their surface modifiers: leafing aluminum pigments, non-leafing aluminum pigments, water-based aluminum pigments, and resin-coated aluminum pigments.
The leafing type means that aluminum pigment particles float in the substrates. Non-leafing type means that the aluminum pigment particles have no floating property, and the carrier is suspended and deposited in the middle or bottom of the film layer after film formation. Water-based aluminum pigment means that the aluminum pigment particles can be uniformly dispersed in the water-based coating system, and have a certain corrosion resistance, and the phenomenon of "gassing" is not easy to occur in the water-based coating system. Resin-coated type means that the polymer formed after the chemical reaction of the aluminum pigment is coated on the surface of the flake-shaped aluminum particles. It is suitable for acid and alkali resistance, high temperature resistance and voltage resistance coating system with high requirements.
2. Classification according to the particle size of aluminum pigments
Aluminum pigments are divided into fine silver, fine flash silver and coarse flash silver according to their particle size.
Fine silver means that the particle size of the aluminum pigment is 3-14μm, which is characterized by fine particles, good whiteness, and good hiding power. Fine flash silver means that the particle size of aluminum pigment is 15-30μm, which is characterized by moderate particle size, certain brightness and flash effect, and good hiding power at the same time. Coarse flash silver means that the particle size of the aluminum pigment is above 30 μm, which is characterized by a larger particle size, higher brightness and flash effect.
3. Classification according to the state of aluminum pigments
Aluminum pigments are divided into aluminum silver powder (also known as flake aluminum powder), aluminum silver paste (aluminum paste), vacuum aluminum plating suspension and pelletized aluminum pigment according to their existing state.
Aluminum silver powder refers to dry ball milling or wet ball milling and then coating treatment to remove the solvent, the solvent content is less than 5%, mainly used for powder coatings. Aluminum silver paste is obtained by wet ball milling, with a solvent content of 30-40%, and is mainly used in coatings and inks. Vacuum aluminum plating suspension refers to the preparation of nano-scale aluminum film by physical method, then collecting it, and obtaining nano-scale flaky aluminum powder after crushing, and finally adding corresponding additives and solvents to make nano-sheets with mirror effect aluminum paste. The content of aluminum particles is 8-12%, and it is mainly used in coatings or inks that require high brightness or mirror effect. Pelletized aluminum pigment is made by removing excess solvent from aluminum silver paste, adding resin and additives, and extruding through an extruder. The resin content is 20-30%, the solvent content is less than 5%, and it is mainly used in plastics or inks.
4. Classification according to the shape of aluminum particles
According to the shape of aluminum particles, aluminum pigments are divided into irregular-shaped cornflake type and regular-shaped silver dollar type.
Rough and irregular cornflake-shaped aluminum particles have a lot of scattering of light, and the appearance is diffuse reflection. The surface of silver dollar type aluminum particles is smooth, which produces mirror like reflection, and the aluminum particles have good flashing and reflection effects.