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:
Nov. 13, 1979
Filed:
Feb. 27, 1978
Takashi Komine, Yokohama, JP;
Akira Yokota, Yamato, JP;
Hisashi Nakane, Kawasaki, JP;
Shingo Asaumi, Fujisawa, JP;
Noboru Okazaki, Chigasaki, JP;
Tokyo Ohka Kogyo Kabushiki Kaisha, Kawasaki, JP;
Abstract
A gallic acid alkyl ester or a gallic acid aryl ester is reacted in an inert solvent with 3 equivalents of naphthoquinone-(1,2)-diazido-(2)-sulfonyl chloride in the presence of an alkali to effect sulfonylation of 3 hydroxyl groups in the gallic acid moiety whereby a photodecomposable naphthoquinone-(1,2)-diazido-(2)-sulfonic acid ester is obtained. The new naphthoquinonediazido derivative thus obtained is mixed with an alkali-soluble phenol resin such as m-cresol novolac resin or phenol novolac resin to prepare a positive-type photoresist composition having high sensitivity and high resolving power as well as excellent dimensional accuracy and etching-resistance. In addition, this composition forms a good photosensitive film and can be a good ink receptor.