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. 15, 2000
Filed:
Jun. 16, 1997
Haruhiko Kikkawa, Yokohama, JP;
Fumio Kataoka, Yokohama, JP;
Issei Takemoto, Hiratsuka, JP;
Jun Tanaka, Chigasaki, JP;
Keiko Isoda, Tokyo, JP;
Shunichiro Uchimura, Hitachi, JP;
Makoto Kaji, Hitachi, JP;
Minoru Sugiura, Hitachi, JP;
Abstract
A polyimide precursor having repeating units of the formula: ##STR1## wherein R.sup.1 is a tetravalent organic group having 4 or more carbon atoms; R.sup.2 is a trivalent or tetravalent organic group having one or more aromatic rings; R.sup.3 is a monovalent organic group; A is a monovalent group showing acidity; and n is an integer of 1 or 2, is effective for preparing a highly sensitive negative-working photosensitive material developable with an alkaline aqueous solution in a short time with high resolution.