06.12.08
Patent No. U.S. 7,264,672 B1
National Titanium Dioxide Co. Ltd. has obtained a patent for a process of making titanium dioxide particles, comprised of forming a slurry comprising particles and a phosphate-containing agent, the particles comprising titanium dioxide and alumina; milling the slurry to form a homogeneous dispersion comprised of milled particles; leaching the alumina off of the milled particles to form leached particles in a leached dispersion; treating the leached dispersion under conditions to react the leached alumina with the phosphate-containing agent to form aluminum phosphate and to coat the leached particles with the aluminum phosphate and form a slurry of coated particles.
National Titanium Dioxide Co. Ltd. has obtained a patent for a process of making titanium dioxide particles, comprised of forming a slurry comprising particles and a phosphate-containing agent, the particles comprising titanium dioxide and alumina; milling the slurry to form a homogeneous dispersion comprised of milled particles; leaching the alumina off of the milled particles to form leached particles in a leached dispersion; treating the leached dispersion under conditions to react the leached alumina with the phosphate-containing agent to form aluminum phosphate and to coat the leached particles with the aluminum phosphate and form a slurry of coated particles.