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. 07, 1989
Filed:
Oct. 24, 1988
Applicant:
Inventors:
J Kenneth Presswood, Baton Rouge, LA (US);
Alethea H O'Quinn, Baton Rouge, LA (US);
Assignee:
Ethyl Corporation, Richmond, VA (US);
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
B32B / ; B32B / ; B32B / ;
U.S. Cl.
CPC ...
428408 ; 4284735 ; 528185 ; 427113 ; 4273855 ; 427421 ;
Abstract
Described is a way of sealing a carbon body such as monolithic graphite tooling so that it retains its vacuum integrity through numerous thermal cycles typical of thermoplastic processing. This is accomplished by (a) applying to the body surface a coating formulation composed of a carbon-filled solution of a polyamic acid formed by reaction between pyromellitic acid dianhydride and 2,2-bis[4-(aminophenoxy)phenyl]hexafluoropropane, and (b) heat curing the coated body to cause the polyamic acid to imidize into a thermally cured polyimide.