Fillers are also known as extender pigments. This pigment has a small tinting strength and a low hiding power, and is a white and colorless ultrafine powder. It is dispersed in a powder coating together with a coloring pigment to enhance the mechanical strength of the powder coating. And the following conditions should be met:
1, insoluble in water and organic solvents, has very good dispersibility, colorless or white, ultra-fine particles without impurities;
2, acid, alkali and weather resistance;
3. Low cost.
Commonly used fillers in powder coatings include precipitated barium sulfate, barite powder, light calcium carbonate, heavy calcium carbonate, kaolin, talc, bentonite, precipitated silica, mica powder, quartz powder and silicon micropowder.
Each filler plays a different role in the powder coating formulation. This paper discusses the effects of precipitated barium sulfate, mica powder, hollow glass microbeads and nano-silica on the properties of powder coating products.