CHEMICALLY AGGREGATED KAOLIN CLAY PIGMENT AND PROCESS FOR MAKING THE SAME BY PHOSPHATE BONDING

摘要

An opacifying kaolin pigment with improved porosity, light scattering ability (opacity), gloss, and ink receptivity over that of the starting pigment is manufactured by a process which comprises the steps of treating an aqueous solution of kaolin with a phosphate compound, using the endogenous aluminum leached from kaolin and/or adding a soluble aluminum compound and increasing the pH of the mixture. The kaolin aggregates are prepared at temperatures between 5 DEG C and 200 DEG C.