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:
Mar. 16, 2004
Filed:
Jul. 23, 2001
Tatsuo Tsumiyama, Ube, JP;
Ube Industries, Ltd., Yamaguchi-ken, JP;
Abstract
A process for production of polyimide molded bodies which comprises a step in which a polyimide resin powder obtained by polymerization and imidation of p-phenylenediamine with 3,3,4,4′-biphenyltetracarboxylic acid, its ester or its dianhydride and 2,3,3′,4′-biphenyltetracarboxylic acid, its ester or its dianhydride is molded at a pressure of approximately 800-5,000 kgf/cm , a step in which the pressurized body is subjected to calcination at about 450-550° C. under low pressure, a step in which the calcined molded body is vacuum encapsulated into a metal capsule, and a step in which the encapsulated molded body is isotropically subjected to hot compression at approximately 460-550° C. in an inert gas atmosphere such as argon. The polyimide molded bodies obtained thereby have a density in the range of 1.44-1.38 g/cm .