Patent ID: 6494924
Filing Date: 2002-12-17
Classification: C09B,C09D,D06P

Abstract:
A process for preparing a precipitated, water-insoluble or sparingly water-soluble dye in colloidally disperse form having an average particle size within the range from 5 nm to 5 &mgr;m and having a variance of less than 50%; both measured by quasi-elastic light scattering and evaluation by the cumulant method, which comprisesa) precipitating the dye from a solution in a water-miscible organic solvent by addition of an aqueous phase, or b) precipitating the dye in an aqueous phase from an emulsion which is obtainable by emulsifying a solution of the dye in a water-immiscible organic solvent and which includes a protective colloid by stripping off the solvent.