Pearlescent pigment based on fine, thin substrates

摘要

Pearlescent pigment comprises a substantially transparent, platelet-shaped substrate having a thickness of delta sand at least one optically active coating having a thickness of delta m, where the substrate has an average size (d 5 0) of 3-8 mu m and an average height (h s) of 40-110 nm. Independent claims are included for: (1) a method for preparing the pearlescent pigment, comprising (a) classifying the transparent substrate to obtain a substrate having an average height (h s) of 40-110 nm and (b) coating the classified substrate with an optically active, preferably highly refractive, layer to obtain a pearlescent pigment having an average size (d 5 0) of 3-8 mu m; and (2) a method for calculating the average layer thickness (h s) of a platelet-shaped substrate, which is an effective pigment comprising a platelet-shaped substrate having a thickness of delta sand at least one optically active coating having a thickness of delta maccording to a formula given in the specification.