US Patent Issued to Evonik on Nov. 11 for "Organophilic clays and drilling fluids containing them" (Virginia, New Jersey Inventors)

ALEXANDRIA, Va., Nov. 11 -- United States Patent no. 12,466,985, issued on Nov. 11, was assigned to Evonik Corp. (Parsippany, N.J.).

"Organophilic clays and drilling fluids containing them" was invented by Sarah Smith (Prince George, Va.), Gary Davis (Westampton, N.J.), Dennis Parrish (Sandston, Va.) and Miyako Hisamoto (Glen Allen, Va.).

According to the abstract* released by the U.S. Patent & Trademark Office: "The organophilic clay comprises a smectite-type clay ion exchanged with quaternary ammonium ions, where at least 75 mol-% of said quaternary ammonium ions are bis-(2-hydroxypropyl)-dimethylammonium fatty acid esters and at least 90% of the fatty acid moieties of the bis-(2-hydroxypropyl)-dimethylammonium fatty acid esters have a ...