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:
Apr. 10, 1990
Filed:
Jul. 27, 1988
Atsushi Hino, Osaka, JP;
Yuzuru Noda, Osaka, JP;
Nitto Electric Industrial Co., Ltd., Osaka, JP;
Abstract
A flexible printing base comprising a metal foil having formed thereon a polyimide layer is disclosed, wherein said metal foil has a centerline average roughness of not more than 0.7 .mu.m, and said polyimide mainly comprises a repeating unit represented by formula (I): ##STR1## and a repeating unit represented by formula (II): ##STR2## wherein l:m=x:y, wherein x represents a number not less than 45 and less than 70; y represents a number more than 30 and not more than 55; and x+y=100, said polyimide layer is formed by applying a solution of a polyamic acid mainly comprising a repeating unit represented by formula (III): ##STR3## and a repeating unit represented by formula (IV): ##STR4## wherein l and m are as defined above, in N,N'-dimethylformamide and/or N,N'-dimethylacetamide on a metal foil, followed by imidation. The flexible printing base is quite free from curling either in the state of a composite laminate but also in the state where the metal foil has been removed by etching.