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:
Oct. 07, 1980
Filed:
Apr. 30, 1979
Applicant:
Inventors:
Motoyuki Yamato, Kamakura, JP;
Tadao Natsuume, Yokosuka, JP;
Assignee:
Nippon Zeon Co. Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C07D / ;
U.S. Cl.
CPC ...
2603463 ;
Abstract
A process for isomerizing methyl-delta-4-tetrahydrophthalic anhydride, which comprises heat-treating it at 60.degree. to 300.degree. C. for 0.1 to 30 hours in the presence of at least one nitrogen-containing compound selected from the group consisting of (a) a quaternary ammonium compound and (b) a compound having a nitrogen atom bonded to the carbon atom of the carbonyl group (e.g., an amide, imide, carbamate, urea or semicarbazide compound). The product is liquid at room temperature, and especially suitable for use as a curing agent for epoxy resins.