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:
Feb. 05, 2002
Filed:
Nov. 15, 1999
Applicant:
Inventors:
Assignee:
Sony Chemicals Corp., Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G03C 5/00 ;
U.S. Cl.
CPC ...
G03C 5/00 ;
Abstract
A flexible circuit board comprises a polyimide insulating layer with land access holes and a conductor circuit layer provided thereon, and is produced by coating one surface of a conductor circuit metal foil side with a polyimide precursor varnish, which is dried to give a polyimide precursor layer , where the polyimide precursor layer is provided with land access holes by a photolithography process; the conductor circuit metal foil is patterned by the subtractive process to form conductor circuit layer ; and the polyimide precursor layer is then imidated to form polyimide insulating layer