Weather stable pearlescent pigments

Abstract

Weather stable pearlescent pigment having a basic pearlescent with an interference color which comprises a transparent platelet-shaped substrate and at least one metal oxide layer with a refractive index >1.8 and on top of this basic pearlescent pigment a weather stabilizing top coating comprising at least one metal oxide and an organofunctional surface modification, wherein a) for a basic pearlescent pigment with silvery interference color the weather stabilizing top coating consists of a first metal oxide of a rare earth metal M1 from the group consisting of Y, La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu and mixtures thereof, or b) for a basic pearlescent pigment with a colored interference color or a silvery interference color the weather stabilizing top coating comprises a first metal oxide of a rare earth metal M1 from the group consisting of Y, La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu and mixtures thereof, and a second metal oxide from a second metal M2 from the group consisting of Si, Al, Zn, Mg, Zr, Sn and mixtures or combinations thereof, and in each case a) or b) the organofunctional surface modification comprises organofunctional silanes or water-based pre-condensated organofunctional silanes.

Dependencies are inferred from the claim text.