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:
Oct. 20, 1992
Filed:
Apr. 04, 1989
Hiromi Ito, Amagasaki, JP;
Ichiro Takahashi, Amagasaki, JP;
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Abstract
An epoxy resin composition for encapsulating a semiconductor device comprises a flexibilizer obtained by pre-reaction of an epoxy resin and at least one modified silicone oil having the formula: ##STR1## where R.sub.1, R.sub.3, and R.sub.4 are divalent organic groups; R.sub.21, R.sub.22, R.sub.23, R.sub.24, R.sub.25, R.sub.26, and R.sub.27 are respectively selected from the group consisting of an alkyl group having from 1 to 5 carbon atoms, a hydroxyalkyl group having from 1 to 5 carbon atoms, an alkoxy group having from 1 to 5 carbon atoms, a phenyl group, and a fluorine-substituted alkyl group having from 1 to 5 carbon atoms; a is an integer from 10 to 300; and b is an integer from 2 to 10, in which 0.ltoreq.b/(a+b).ltoreq.0.32, and wherein the equivalent ratio of phenolic hydroxyl groups in said modified silicone oil to epoxy groups of the epoxy resin of the flexibilizer is from 0.001 to 0.4:1; an epoxy resin other than the flexibilizer; and a curing agent.