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:
Aug. 24, 2010
Filed:
Feb. 08, 2006
Michael J. Garska, Sandersville, GA (US);
Ismail Yildirum, Milledgeville, GA (US);
Robert J. Pruett, Milledgeville, GA (US);
Johnny W. Larimore, Sandersville, GA (US);
Michael J. Garska, Sandersville, GA (US);
Ismail Yildirum, Milledgeville, GA (US);
Robert J. Pruett, Milledgeville, GA (US);
Johnny W. Larimore, Sandersville, GA (US);
Imerys Pigments, Inc., Roswell, GA (US);
Abstract
The Rio Capim Kaolin deposit contains a lower bed of soft kaolin clay that averages 10 meters thick, and an upper bed of 'hard' kaolin ('RCC hard kaolin') that may be as thick as 6 to 8 meters. Due to their high impurity content fine particle size, cementetious nature, and high degree of particle aggregation, hard kaolins are difficult to process. Disclosed herein are compositions comprising kaolin having a particle size distribution such that at least about 90% of the kaolin has a particle size of less than 1 micron and a GE brightness of at least about 91, where the kaolin may be derived from a crude kaolin having a FeOcontent of at least about 1.0% by weight, and optionally comprises titania in an amount of at least about 1.5% by weight. Also disclosed herein are methods of refining the hard kaolins, such as RCC hard kaolins, by dispersing the kaolin with at least one anionic organic dispersant and at least one inorganic dispersant. Also disclosed are compositions comprising an aqueous kaolin slurry comprising the hard kaolin, such as an RCC hard kaolin, at least one anionic organic dispersant, and at least one inorganic dispersant. Also disclosed are products containing the refined kaolin, such as paints, paper coatings, and plastics.