Patent · US Expired

Modified rosin ester preparation

US4643848A · kind A · utility

16Cited by
11References
20Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 21, 1986
Grant dateFeb 17, 1987
Priority date
Expiry dateFeb 21, 2006

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC09F1/04
  • WIPO fieldBasic materials chemistry
  • WIPO sectorChemistry

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.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.