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:
Mar. 27, 1990
Filed:
Oct. 21, 1988
Applicant:
Inventors:
Assignee:
Hitachi Chemical Company, Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C07C / ; C07C / ;
U.S. Cl.
CPC ...
549241 ; 562410 ; 562412 ; 562413 ; 562415 ; 562488 ;
Abstract
Disclosed are a para- or meta-terphenyl-3,4,3',4'-tetracarboxylic acid or a dianhydride and a process for preparing the same. The para- or meta-terphenyl-3,4,3',4'-tetracarboxylic acid or a dianhydride thereof according to the present invention is a novel compound which is useful as a raw material for a polyimide having higher heat resistance and so on.