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:
Aug. 03, 1999
Filed:
Dec. 19, 1995
Stephen Leslie Buchwalter, Hopewell Junction, NY (US);
Joseph Paul Kuczynski, Rochester, MN (US);
John Gregory Stephanie, Rochester, MN (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A cleavable epoxy resin composition suitable for encapsulating electronic chips and a method for making the composition comprises the cured reaction product of a diepoxide; a cyclic dicarboxylic anhydride curing agent mixture; a 1,3-diaza compound having two nitrogen atoms present with one nitrogen atom doubly bonded to the central carbon and singly bonded to one other carbon, and the other nitrogen atom singly bonded to the central carbon and singly bonded to another carbon and singly bonded to a hydrogen. The 1,3-diaza compound serves either as the sole catalyst or in combination with a tertiary amine catalyst different from the diaza compound. The composition may include an optional hydroxy functional compound capable of reacting with the cyclic anhydrides to form a half ester thereby initiating the reaction between the diepoxide and the cyclic dicarboxylic anhydride curing agent. The resin can be used for the encapsulation of electronic parts, but can be removed by a solvent. This feature allows electronic components to be recycled.