Multilayer pearlescent pigments comprise a lamellar substrate with a high refractive index, a layer of a material with a low refractive index and a semitransparent metallic layer

摘要

Multilayer pearlescent pigments (I) comprise: (a) a lamellar substrate with a refractive index (RI) above 1.8; (b) a layer of a material with a RI of 1.35-1.8; (c) optionally a layer of a material with a RI above 1.8; (d) a semitransparent metallic layer deposited on component (a), (b) or (c); and (e) optionally an overcoat layer. Independent claims are also included for the following: (1) production of (I) by: (i) depositing a thin film of a substrate precursor on an endless belt; (ii) drying the film to convert the precursor into a metal oxide; (iii) releasing the film from the belt; (iv) washing the resulting substrate particles and resuspending them in a coating solution; (v) coating the substrate particles with several layers of metal oxides or metals; and (vi) overcoating the resulting pigment particles; (2) lacquers, printing inks, plastics, cosmetics, ceramics, glasses and polymer films containing (I); (3) laser-markable plastics containing (I).