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:
May. 08, 1984
Filed:
Nov. 04, 1982
Applicant:
Inventors:
Assignee:
Hitachi Chemical Co., Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C08G / ;
U.S. Cl.
CPC ...
528 45 ; 528 49 ; 528 52 ; 528 53 ; 528 73 ;
Abstract
A polyamide-imide resin which can give a varnish having a high resin content, excellent in storage stability and heat resistant final products can be produced by reacting an aromatic diisocyanate with a tricarboxylic acid anhydride in the presence of a basic solvent while adjusting the resin content at 40% by weight or more, and adding a specific amount of lactam and a specific amount of an alcohol and/or an oxime separately before, during or after the above-mentioned reaction so as to adjust the reduced viscosity of the resin to 0.10 to 0.27.