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. 20, 2003
Filed:
Apr. 20, 2001
Peter Gspaltl, Grambach, AT;
Christian Schlossnikl, Vöcklabruck, AT;
Lenzing Aktiengesellschaft, Lenzing, AT;
Abstract
The invention relates to a process for the production of cellulosic flat films whereby a solution of cellulose is extruded in an aqueous tertiary amine oxide by means of an extrusion die which has an extrusion gap whereby the solution is moulded in the shape of a film and the extruded solution is led via an air gap to a precipitation bath. The process in accordance with the invention is characterized in that an extrusion die is used which has an extrusion gap b of 220 &mgr;m≦b≦280 &mgr;m. Moreover, the invention relates to flat films, obtainable by the amine oxide process with a thickness d of less than 20 &mgr;m, a width B of more than 30 cm, and a factor f of 65 or less, whereby f is defined as f=d*(MD/TD), d is used in &mgr;m and whereby MD stands for the tenacity of the film in the longitudinal direction (N/mm ) and TD for the tenacity of the film in the transverse direction (N/mm ).