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:
Feb. 17, 1987
Filed:
Feb. 21, 1986
John H Thomas, Jacksonville, FL (US);
Don P Duncan, Mt. Pleasant, SC (US);
Michael A Lake, Mt. Pleasant, SC (US);
Gary B Womack, Charleston, SC (US);
Westvaco Corporation, New York, NY (US);
Abstract
Phosphinic acid (also called hypophosphorous acid), when used in very small quantities, is disclosed to act as a catalyst to accelerate the reaction of rosin with an unsaturated dibasic acid to form a modified rosin for subsequent esterification with a polyhydric alcohol. According to the process of the invention, a rosin is reacted with an unsaturated dibasic acid such as maleic anhydride or fumaric acid in the presence of phosphinic acid at a temperature of from about 180.degree. C. to about 220.degree. C. When the modified rosin is subsequently esterified, the rosin ester exhibits improved color, softening point, and viscosity in a specified solution.