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:
Aug. 11, 1981
Filed:
Dec. 19, 1979
Applicant:
Inventors:
Motoyuki Yamato, Kamakura, JP;
Tadao Natsuume, Yokosuka, JP;
Assignee:
Nippon Zeon Co. Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C07D / ;
U.S. Cl.
CPC ...
2603463 ;
Abstract
A dibasic acid anhydride which is liquid at 0.degree. C., or even at -20.degree. C., is produced by heat-treating in the presence of a stereoisomerization catalyst a structural isomeric mixture obtained by shifting the double bond of methyl-tetrahydrophthalic anhydride. The liquid dibasic acid anhydride is useful as a curing agent for epoxy resins.