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. 05, 1985
Filed:
Oct. 19, 1983
Applicant:
Inventor:
Edward A Burkard, East Amherst, NY (US);
Assignee:
National Gypsum Company, Dallas, TX (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
B32B / ;
U.S. Cl.
CPC ...
156 39 ; 106109 ; 423171 ; 428703 ;
Abstract
By-product gypsum, which is formed during a flue gas desulfurization process, (FGD gypsum) is carefully formed as an aqueous slurry of crystals having a mean particle diameter of between about 35 microns and 80 microns and filtered, which filter cake is substantially completely dried before calcination, without any substantial grinding action, the crystals are then flash calcined to a hemihydrate, then ground, to reduce consistency, and then formed into an aqueous slurry from which a paper-covered gypsum board is formed of superior core quality.