Patent ID: 7399354
Filing Date: 2008-07-15
Classification: C09B

Abstract:
1. A process for producing a readily dispersible granular wax-coated pigment particle having a particle size distribution in the range from 0.05 to 5.0 mm, said process comprising a) mixing an aqueous suspension of an organic pigment with an aqueous emulsion of a waxy additive to form an aqueous emulsion mixture, b) coagulating the aqueous emulsion mixture to form an aqueous dispersion wherein the waxy additive is partially or fully disposed on the organic pigment, c) diluting the aqueous dispersion with water and homogenizing to form a homogenized suspension, and d) spray drying the homogenized suspension to form a dustless and free-flowing, readily dispersible wax-coated pigment granule comprising from 50 to 99 percent by weight of the organic pigment and from 1 to 50 percent weight of the waxy additive based on said pigment particle, wherein the process uses no organic solvents.