Kerr-mcgee Chemical, LLC

Kerr-mcgee Corporation

Kelly A Green

Phillip M Story

John E Halko

James W Kauffman

Thomas Ian Brownbridge

John R Brand

A process for preparing a low-dusting, free-flowing pigment which has not been subjected to any micronizing treatment comprising the steps of providing an inorganic pigment material; providing a source of water; forming a fine, well dispersed slurry of the pigment and water; milling the slurry; depositing a treating agent having the formula ROOCCHSO.sub.3 MCH.sub.2 COOR' wherein R and R' are monovalent alkyl radicals having from about 2 to about 20 carbon atoms, and M is a metallic monovalent cation on the slurried milled pigment; and drying the pigment material having a treating agent deposited thereon. The invention also provides the free-flowing pigments produced by this process.

Process for preparing an improved low-dusting, free-flowing pigment

Improved alumina-coated inorganic pigments having a first coating of boehmite alumina, a second coating of amorphous alumina, and a third coating of boehmite alumina which exhibit good durability, dispersibility, and optical properties in plastic compositions are disclosed. Also disclosed is a process whereby an aqueous slurry of an alumina-containing inorganic pigment is milled to achieve a particular particle size distribution, a first coating of boehmite alumina is precipitated onto the pigment material within a first pH range, a second amount of an alumina coating agent is added to the aqueous slurry within a second pH range to obtain a second coating of amorphous alumina over the first boehmite alumina coating, and then the pH of the slurry is adjusted to a third pH range thus forming a third boehmite alumina coating over the second amorphous alumina coating.

Durable pigments for plastic

A titanium dioxide production method, a novel titanium dioxide product produced by the inventive titanium dioxide production method, a method for producing a plastic product using the novel titanium dioxide product, and a novel plastic product formed by the inventive plastic product production method. The inventive titanium dioxide production method comprises the steps of: (a) forming a mixture comprising a titanium dioxide material in a liquid medium; (b) wet milling the titanium dioxide material in the liquid medium; (c) after step (b), reducing the pH of the mixture to a value not exceeding 4.0; (d) after step (c), adding an effective amount of a base to the mixture to cause the titanium dioxide material to flocculate; (e) removing the flocculated titanium dioxide material from the mixture; and (f) washing the titanium dioxide material. The titanium dioxide material used in step (a) is an agglomerated titanium dioxide material which has been produced by a reaction process. Other than any inorganic oxides formed in the reaction process along with the titanium dioxide material, the titanium dioxide material used in step (a) has substantially no inorganic oxides deposited thereon. Additionally, other than any redeposited inorganic oxides originally produced in the reaction process along with the titanium dioxide material, substantially no inorganic oxides are deposited on the titanium dioxide material during the course of the inventive titanium dioxide production method.

Titanium dioxide dispersibility

The present invention provides a pigmentary titanium composite having good durability and excellent optical properties. The inventive composite consists essentially of: a particulate titanium dioxide base; a hydrous zirconium oxide layer deposited on the titanium dioxide base; and a hydrous alumina layer deposited on the hydrous zirconium oxide layer. The alumina layer consists essentially of boehmite alumina and/or pseudoboehmite alumina. The present invention also provides a method for preparing the inventive pigmentary composite. The inventive method comprises the steps of: (a) preparing an aqueous slurry comprising water and a particulate titanium dioxide base; (b) depositing a layer of a hydrous zirconium oxide precipitate on the titanium dioxide base; and (c) depositing a layer of a hydrous alumina precipitate on the layer of hydrous zirconium oxide. The hydrous alumina precipitate consists essentially of boehmite alumina and/or pseudoboehmite alumina.

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Edmond, OK, United States of America

Kelly A Green