Patent ID: 6653356
Filing Date: 2003-11-25
Classification: B01J,B82Y,C01G,C01P,C09C

Abstract:
A process of producing a sol of particulate titanium dioxide comprising:a) mixing an alkaline-reacting liquid with an aqueous solution of titanyl sulphate at elevated temperature until the resultant mixture reacts acidically and is neutralized to a pH between 5 and 9, forming flocculates of titanium dioxide nanoparticles; b) first-isolating the formed titanium dioxide nanoparticle flocculate; c) first-washing in water the isolated titanium dioxide nanoparticle flocculate; d) second-washing in an acid or an alkali the first-isolated and first-washed nanoparticle flocculate, e) second-isolating as a product of the second-washing an acidic or an alkaline titania concentrate of titanium dioxide; and f) dispersing the second-isolated titania concentrate in a polar sol-forming medium to make a sol suitable to serve as a coating in which sol is present particulate titanium dioxide.