Patent No. U.S. 7,255,736 B2
Merck Patent GmbH has been granted a patent for an effect pigment, which is a silver-white effect pigment, a colored interference pigment or an effect pigment having a non-flake appearance comprising an SiO2 flake substrate having a thickness of from 50 nm to 150 nm, coated with only one layer of a metal oxide, metal oxide hydrate, metal suboxide, or metal fluoride or only one layer of a mixture of two or more of these materials.