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:
Sep. 16, 2003
Filed:
Jul. 02, 2001
Masahiro Yuyama, Ibaraki-ken, JP;
Hitoshi Arai, Ibaraki-ken, JP;
Yoshitsugu Eguchi, Ibaraki-ken, JP;
Shin-Etsu Chemical Co., Ltd., Tokyo, JP;
Abstract
The subject matter of the invention is a base sheet for the preparation of a flexible printed circuit board which is a three-layered laminate consisting of (a) an electrically insulating film of a plastic resin such as a polyimide, (b) an epoxy resin-based adhesive layer and (c) a copper foil bonded to the film (a) with intervention of the adhesive layer (b). The base sheet can exhibit excellent performance in respect of peeling resistance, soldering heat resistance, dimensional stability and solvent resistance as well as workability into a printed circuit board only when each of the layers (a), (b) and (c) has a specified thickness in a narrow range of 10-30 &mgr;m, 5-15 &mgr;m and 5-15 &mgr;m, respectively.