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:
May. 04, 2004
Filed:
May. 01, 2002
Applicant:
Inventors:
Akira Katano, Kanagawa, JP;
Mitsuo Hagihara, Kanagawa, JP;
Ken Miyagi, Kanagawa, JP;
Toshiaki Tachi, Kanagawa, JP;
Assignee:
Tokyo Ohka Kogyo Co., Ltd., Kanagawa, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C08G 1/404 ;
U.S. Cl.
CPC ...
C08G 1/404 ;
Abstract
(i) As a primary reaction, m-cresol is allowed to react with propionaldehyde in the presence of an acid catalyst and thereby yields a polymer having a weight average molecular weight Mw of 200 to 500 and a molecular weight distribution Mw/Mn of 1.7 or less, and (ii) as a secondary reaction, the polymer is allowed to react with 3,4-xylenol and formaldehyde and thereby yields a novolak resin having an Mw of 1000 to 20000. By adding a specific photosensitizer, the novolak resin yields a positive photoresist composition.