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:
Apr. 02, 1996
Filed:
Jan. 10, 1995
Robert W Schluenz, Panama City, FL (US);
Paul S Douglas, Gulf Breeze, FL (US);
Arizona Chemical Company, Panama City, FL (US);
Abstract
The specification discloses a method for esterifying rosins with a polyol which comprises contacting rosin with the polyol in the presence of a bleaching mixture which includes both an alkaline earth hypophosphite and hypophosphorous acid and, preferably also, an organic sulfide, under esterification conditions to produce a rosin ester. The method enables production of rosin esters which have a color of less than about 5 Gardner neat. The preferred bleaching mixture includes from about 0.01% to about 0.10% of the alkaline earth hypophosphite and from about 0.10% to about 0.15% of active hypophosphorous acid, where the amounts are based on the weight of the rosin. The most preferred alkaline earth hypophosphite is calcium hypophosphite. The specification also describes a method for preparing an adhesive from the rosin ester.