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:
Dec. 11, 2001
Filed:
Nov. 01, 1999
Applicant:
Inventors:
Noriyoshi Arai, Hitachi, JP;
Makoto Kaji, Hitachi, JP;
Akihiro Sasaki, Hitachi, JP;
Toshiki Hagiwara, Sagamihara, JP;
Assignee:
Other;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C08G 7/300 ;
U.S. Cl.
CPC ...
C08G 7/300 ;
Abstract
A 6,6′-dialkyl-3,3′4,4′-biphenyltetracarboxylic dianhydride is prepared by brominating a 4-alkylphthalic anhydride at its 5-position, and coupling the bromination product in the presence of a nickel catalyst; A photosensitive resin composition containing a polyimide precursor having repetitive units of general formula (7) is applied onto a substrate, exposed to i-line, developed and heated to form a polyimide relief pattern