Pearl pigments are composed of several metal oxide layers of moldy mica. Pearl pigments change the thin layer of metal oxide to produce different pearlescent effects. Compared with other pigments, pearl pigments have an unparalleled effect on the unique soft pearl luster. The special surface structure, high refractive index and good transparency make it the same effect as pearl pearl in a transparent medium.
The excellent chemical and high temperature resistance of pearl pigments offers its potential for wide application in coatings, inks, plastics and many other fields. They provide a new color system and color quality for these products. Pearl pigments are low in heavy metal and meet the safety standards for rent security, so they can be used in food packaging and children's toys. Both acid and alkali can not attack pearl pigment at room temperature. Pearl pigment can not burn, is not self-igniting, is not conductive, and can withstand high temperatures of 600~800 °C. Pearlescent pigments can also be used in reactive coatings for radiation curing systems (electron multiply curing, photocuring). The special surface chemical structure of pearl pigment makes it excellent in hydrophilicity, so it can be applied to water-based paints, but it has poor lipophilicity. Therefore,when used in an organic system, the problem of poor dispersibility may occur, and the pearl pigment needs to be surface-treated. So that it can be well applied to organic systems.
Pearl pigments are mainly divided into the following categories:
1. Pearlescent powder Pearl powder is divided into ordinary powdery pearlescent material and pearlescent ball dispersed by soft resin. The color mainly includes silver, bright gold, metallic color, rainbow interference color and chameleon series, among which pearl powder is used according to the direction of use. The effect is different in particle size. The smaller the particle size, the stronger the hiding power of pearl powder. The larger the particle size, the stronger the gloss of pearl powder. In the printing industry, the particle size has strict requirements, and the small particle size can be used. Offset printing, larger particle size can be used for flexo and gravure, and has a better effect.
2. Bead Pearlescent Pulp is a kind of high viscosity viscose pearl material. It is suitable for mixing with offset ink. It has excellent hiding power and good gloss and is suitable for offset printing.