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. 11, 2009
Filed:
Jun. 14, 2005
Dennis M. Lettkeman, Watonga, OK (US);
Qingxia Liu, Vernon Hills, IL (US);
John W. Wilson, Fairview, OK (US);
Brian S. Randall, Fairview, OK (US);
David R. Blackburn, Barrington, IL (US);
Michael P. Shake, Johnsburg, IL (US);
Dennis M. Lettkeman, Watonga, OK (US);
Qingxia Liu, Vernon Hills, IL (US);
John W. Wilson, Fairview, OK (US);
Brian S. Randall, Fairview, OK (US);
David R. Blackburn, Barrington, IL (US);
Michael P. Shake, Johnsburg, IL (US);
United States Gypsum Company, Chicago, IL (US);
Abstract
A slurry is made including water, at least 50% by weight calcium sulfate hemihydrate, and a specific polycarboxylate dispersant prepared using at least three repeating units. A first repeating unit is a vinyl ether-type repeating unit. A second repeating unit includes a maleic acid-type repeating unit. A third repeating unit includes an acrylic acid-type repeating unit. The polymer dispersant has a molecular weight of from about 20,000 to about 80,000 Daltons. The slurry made from this composition can be made at reduced water levels to speed drying and reduce drying costs.