DuPont patents TITANIUM

February 11, 2009

DuPont patents TITANIUM
Patent No. U.S. 7,371,275 B2
E.I. du Pont de Nemours and Company has received a patent for an improved flexible polyvinyl chloride composition that resists UV light induced yellowing and mechanical degradation, the polyvinyl chloride composition having a coated titanium dioxide white pigment in an amount ranging from 0.5 to 15 parts by weight per 100 part of the polyvinyl chloride, wherein the improvement comprises the titanium dioxide base pigment having a carbon black undertone of at least 16, having a coating of 1.2 %to 10% weight silica and 0.5%-5% weight alumina, based on the total weight of the coated pigment, and the coated pigment having a UV absorption at 340 nm of at least 0.40, a vinyl undertone of at least 0.023, a vinyl tint strength of at least 80 and an acid solubility of no greater than 12% weight based on the total weight of the coated pigment.