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. 17, 1999
Filed:
Apr. 07, 1998
Richard Frederich Sutton, Jr, Circleville, OH (US);
Darrel Eugene Coverdell, Amanda, OH (US);
E. I. du Pont de Nemours and Company, Wilmington, DE (US);
Abstract
An intimate polyimide blend, prepared by chemical conversion, containing from 25 to 50 weight % of a first polyimide derived from 90 to 100 mole % of 3,3', 4,4'-biphenyltetracarboxylic dianhydride, 0 to 10 mole % of pyromellitic dianhydride and p-phenylenediamine and from 50 to 75 weight % of a second polyimide derived from pyromellitic dianhydride, from 20 to 50 mole % of p-phenylenediamine and from 50 to 80 mole % of 4,4'-diaminodiphenylether. The polyimide blend provides blister free films having high modulus and low thermal expansion coefficients for use in electronics applications.