Effect pigments

An effect pigment having a roundish flake-form substrate obtained by a process comprising grinding substrates in the form of flakes to form ground substrate flakes having a diameter of 50-200 μm, subsequently introducing ground substrate flakes into a comminution machine, adding water and/or an organic solvent, and a suspension formed in this way is treated mechanically in the comminution machine, during which the surface of the flakes is polished smooth and the mechanical loading of the substrate flakes is selected so that a permanent shear results in further gentle delamination of flakes and in smoothing of edges and surfaces and a particular-size distribution of 5-60 μm is achieved by a subsequent classification step in the form of a plurality of sedimentation steps, said effect pigment having a circular form factor of 1.2-2,

• wherein the flake-form substrate is synthetic mica flakes, natural mica flakes, SiO2 flakes, Al2O3 flakes, glass flakes, iron oxide flakes, graphite flakes, TiO2 flakes or mixtures thereof,
• wherein the high-refractive-index layer comprises at least one metal oxide, metal sulfide, iron titanate, iron oxide hydrate, titanium suboxide, TiO2, BiOCl, Ce2O3, Cr2O3, COO, Co3O4, Fe2O3, Fe3O4, FeOOH, NiO, SnO2, VO2, V2O3, ZrO2, ZnO, CoAl2O4, BiVO4, Ti3O5, Ti2O3, TiO, Ce2S3, MoS2 or mixtures or mixed phases of said compounds with one another;
• and
• wherein the roundish shape results in increased color saturation and hiding power compared with a non-roundish pigment with oblong shape and greater edge roughness.