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. 28, 1985
Filed:
Sep. 25, 1984
Kazumasa Igarashi, Osaka, JP;
Katsuhiko Yamaguchi, Osaka, JP;
Kazuo Iko, Osaka, JP;
Kazuyuki Miki, Osaka, JP;
Nitto Electric Industrial Co., Ltd., Osaka, JP;
Abstract
A siloxane-modified polyimide precursor which can be converted into a polyimide having excellent adhesion and moisture resistance is produced by simultaneously polymerizing a diaminosiloxane and a diamine containing no silicon atoms in its molecule with 3,3',4,4'-biphenyltetracarboxylic dianhydride, wherein the diaminosiloxane is used in an amount of 1 to 4 mole % per mole of the total diamino compounds and such that the silicon content in the final reaction product is 0.5 wt % or less. The thus obtained precursor solution is further heat aged to reduce the molecular weight of the precursor so that solution viscosity is decreased to a proper level suitable for coating operation.