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:
May. 21, 1991
Filed:
Aug. 10, 1989
Hermann Balk, Troisdorf, DE;
Reifenhauser GmbH & Co. Maschinenfabrik, Troisdorf, DE;
Abstract
A method of and apparatus for continuously stretching a thermoplastic web comprises the steps of feeding the thermoplastic web longitudinally to a heating chamber at a relatively low input speed, engaging the thermoplastic web in the heating chamber with a first member with a relatively low sliding friction between the web and the first member and engaging the thermoplastic web in the heating chamber with a second member spaced longitudinally downstream from the first roller with a relatively high sliding friction between the web and the second member. The thermoplastic web is pulled off the second member in a downstream stretch of the web at a relatively high stretching speed and the web is heated in the chamber to a temperature sufficient to substantially prevent plastic-deformation stretching of the web upstream of the second member.