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. 25, 1980
Filed:
Feb. 13, 1978
Heinz Vetter, Rossdorf, DE;
Ernst Friederich, Darmstadt, DE;
Karl-Heinz Schanz, Traisa, Darmstadt, DE;
Hartmut Schikowsky, Darmstadt, DE;
Rohm GmbH, Darmstadt, DE;
Abstract
A method is disclosed for biaxially stretching a band of thermoplastic resin which comprises attenuating a band of unstretched resin, in a forming zone while the resin is in the thermoelastic condition, by passing the band between two surfaces spaced at a distance less than the thickness of said band of unstretched resin while permitting said band to expand in width, and then cooling said band to a temperature below the softening point of the resin while maintaining the dimensions of the attenuated and expanded band; apparatus for performing such a method is also disclosed.