Patent ID: 6369147
Filing Date: 2002-04-09
Classification: C01P,C09C

Abstract:
A process for the preparation of an effect pigment comprising a core formed of a metallic material having a reflectivity from 40% to 80% and at least one dielectric layer consisting of one or more oxide of a selected metal, comprising the steps of:(a) hydrolyzing a compound of a metal selected from Fe, Ti, or Zr in an aqueous medium having a pH of 1.0 to 4.0, so that said metal is precipitated on the core in the form of its compounds, selected from oxides, hydroxides and mixed hydroxides/oxides; and (b) heating the core with the precipitate of said metal thereon to a temperature of 100Â° C. to 900Â° C., so that substantially any hydroxides in the precipitate of said metal are converted into oxides and any water is eliminated.