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. 08, 1994
Filed:
Mar. 23, 1994
Toshio Shiobara, Annaka, JP;
Koji Futatsumori, Annaka, JP;
Kazuhiro Arai, Annaka, JP;
Hisashi Shimizu, Annaka, JP;
Shigeki Ino, Annaka, JP;
Shin-Etsu Chemical Co., Ltd., Tokyo, JP;
Abstract
Novel fluorine-modified acid anhydrides of formula (1) are useful curing agents typically in epoxy resin compositions for encapsulating semiconductor devices. ##STR1## R.sup.1 is a hydrogen atom, substituted or unsubstituted monovalent hydrocarbon group, hydroxyl group, alkoxy group or alkenyloxy group. Rf is a divalent perfluoroalkylene or perfluoropolyether group of the general formula (2): ##STR2## wherein l is an integer of 0 to 8, k and m are integers of 0 to 15, j and n are 0 or 1, with the proviso that j, k, l, m and n are not equal to 0 at the same time.