The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 31, 2007
Filed:
Sep. 06, 2006
Daniel H. Craig, Edmond, OK (US);
Mark D. Westmeyer, Englewood, OH (US);
Daniel H. Craig, Edmond, OK (US);
Mark D. Westmeyer, Englewood, OH (US);
Tronox LLC, Oklahoma City, OK (US);
Abstract
An improved process for making an organosilicon compound surface-treated titanium dioxide material, comprising (a) forming a mixture of the titanium dioxide material in water, (b) wet milling the mixture, (c) adjusting the pH of the slurry resulting from step (b) to between about 5.0 and about 8.5, (d) after step (c), removing the titanium dioxide material from the mixture by vacuum or pressure filtration, (e) after step (d), washing the titanium dioxide material so removed, (f) after step (e), converting the washed titanium dioxide material to a fluid dispersion having a pH of from about 3.5 to less than about 7 via addition of a fluidizing agent comprising a water-soluble monoprotic acid, (g) after, or concurrently with, step (f), adding to the resulting dispersion of titanium dioxide material an organosilicon compound, with mixing, and (h) spray drying the dispersion of the washed titanium dioxide material resulting from step (g) to yield a dry titanium dioxide pigment powder.