Patent ID: 6899757

Claim:
A method for preparing a pearlescent pigment by coating metal oxides on the synthesized mica, comprising the steps of: (1) grinding the synthesized mica by agitating the mica with water in a wet pulverizer to a particle size between 5 and 500 μm and separating the mica; (2) dispersing the separated particles of the synthesized mica in water and adding 0.0001 to 1.0% by weight of cationic, anionic, nonionic or amphionic surfactant thereto; (3) adding acid to the dispersion containing the surfactant to adjust pH between 1 and 4; (4) adding the metal oxide precursors and the basic aqueous solution thereto while maintaining said pH range until the desired color is attained, and thereby forming at least one hydrous metal oxides layers on the particles of the synthesized mica; and (5) filtering, water-washing, drying and calcining the synthesized mica coated with the metal oxides layers.