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:
Mar. 09, 1999
Filed:
Jan. 07, 1997
Applicant:
Inventors:
W Roy Burke, Tonawanda, NY (US);
Larry W Kingston, North Tonawanda, NY (US);
Assignee:
National Gypsum Company, Charlotte, NC (US);
Primary Examiner:
Int. Cl.
CPC ...
B32B / ;
U.S. Cl.
CPC ...
428703 ; 106778 ; 106802 ;
Abstract
A method of preparation and use of high-strength gypsum wallboard, as well as a core composition suitable for use therein, are disclosed. The core composition includes a slurry of calcium sulfate hemihydrate (stucco), water, and a strengthening agent. The strengthening agent includes an acrylic polymer composition having a glass transition temperature of about 15.degree. C. or greater, and preferably has good divalent ion stability. The method provides wallboard having increased core strength, paper-to-core bonding, and strength-to-weight ratio.