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. 10, 1992
Filed:
Jun. 27, 1989
Yasuharu Yamada, Kitakyushu, JP;
Nobuyuki Furukawa, Kitakyushu, JP;
Masaya Furukawa, Kitakyushu, JP;
Nippon Steel Chemical Co., Ltd., Tokyo, JP;
Abstract
Polyimide copolymers of this invention have a repeating unit of the general formula (1) ##STR1## wherein Ar.sub.1 is a tetravalent organic radical containing at least one aromatic ring, R.sub.1 is a divalent organic radical, R.sub.2 and R.sub.3 are monovalent hydrocarbon radicals, and n is an integer from 0 to 4 and a repeating unit of the general formula (2) ##STR2## wherein Ar.sub.2 is a tetravalent organic radical containing at least one aromatic ring, R.sub.6 is a divalent organic radical, R.sub.7 is a monovalent hydrocarbon radical with 1 to 6 carbon atoms, and l is an integer from 5 to 50 and are capable of forming films of a microdomain structure useful for such applications as protective films on semiconductors, coatings adhesives, moldings, films, and separation membranes.