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:
Jan. 29, 1985
Filed:
Jul. 02, 1982
Koichi Okita, Osaka, JP;
Shigeru Asako, Osaka, JP;
Sumitomo Electric Industries, Ltd., Osaka, JP;
Abstract
A process for producing a tube or rod of a polytetrafluoroethylene is described. The process comprises molding a polytetrafluoroethylene containing a liquid lubricant into a tube or rod by a paste process, removing the liquid lubricant, stretching the tube or rod in the lengthwise direction, and thereafter, by sintering the stretched tube or rod at a temperature of at least 327.degree. C. wherein the stretching of the tube or rod is carried out by the use of at least one pair of heating rolls which are each provided with a plurality of grooves. The process provided uniform stretching making it possible to produce a tube or rod with very small internal diameter.