Patent attributes
The present invention relates to intensely colored red effect pigments comprising iron oxide-coated SiO2 flakes, where the total thickness of the effect pigments is not greater than 500 nm (+/−30 nm). The present invention likewise relates to processes for the preparation of these pigments in which SiO2 flakes are coated with iron oxide, where the thicknesses of the SiO2 flakes and of the iron-oxide layers are selected in such a way that the total thickness of the red effect pigments is not greater than 500 nm (+/−30 nm), and to the use of these pigments in cosmetics, paints, coatings, plastics, films, in security printing, in security features in documents and identity papers, for coloring seed, for coloring foods or in medicament coatings and for the preparation of pigment compositions and dry preparations.
