Abstract: Provided is a method of making improved brightness kaolin clay from an aqueous kaolin clay slurry in which the primary active dispersant is a weak dispersant, at least including the steps of adding to the kaolin clay an effective magnet enhancer reagent wherein the magnet enhancer reagent comprises an aqueous solution of one or more magnetic oxides and one or more surface active agents; conditioning the kaolin clay; and performing high gradient magnetic separation on the conditioned kaolin clay to produce an improved brightness kaolin clay. The method is also applied to decreasing iron- and/or titania-containing impurities in a clay.

Abstract: This invention discloses a process of making composite aggregate pigments (CAPs) having superior optical and dispersion characteristics. These pigments are produced by aggregating titanium dioxide and calcined clay with zirconium hydroxy complex chemicals in a slurry in the pH range of 6.0-10.5. Superior optical properties are obtained by heat treating the pigments after removal from the slurry. Multi-faceted pigments are obtained by including a small amount of a rod-shaped pigment, such as wollastonite, in the composite pigment.

Abstract: A thickening or suspending agent for imparting thixotropic properties to aqueous compositions, particularly LADD formulations, comprises a kaolinite clay admixed to the formulation at a level ranging from about 2% to about 5% by weight. While the thickening or suspending properties of the kaolinite clay are exhibited over a very broad range of particle size products, the kaolinite clay used advantageously has a particle size distribution of at least about 50% of the kaolin particles thereof have a particle size less than 2 microns equivalent spherical diameter, more preferably at least about 80% and, most perferably, at least about 95%. When utilized in a slurry form, the kaolinite clay based thickening or suspending agent most advantageously comprises an aqueous slurry of kaolinite particles at a solids level of at least 65% solids by weight.