Imerys Pigments patents method for separating mixture of finely divided minerals

Patent No. U.S. 7,780,779 B2

Imerys Pigments, Inc. has been granted a patent for a composition comprised of kaolin having a particle size distribution such that at least 90% of the kaolin has a particle size of less than approximately 1 μm and a median particle size (d50) ranging from 0.25 μm to less than 0.35 μm, having an Fe2O3 content in an amount less than approximately 0.8% by weight relative to the total solids content, and a GE brightness of at least 91, the kaolin being derived from a crude kaolin having Fe2O3 in an amount of at least 1.0% by weight, relative to the weight of the crude kaolin and a titania content of at least 1.5% by weight, relative to the weight of the crude kaolin.