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:
Jun. 16, 1998
Filed:
Mar. 27, 1997
Edward Makoto Kajiwara, Park Ridge, IL (US);
Joseph Robert Walta, LaGrange, IL (US);
Ronald Joseph Jerantowski, Hickory Hills, IL (US);
Viskase Corporation, Chicago, IL (US);
Abstract
The tubular extrusion of a thermoplastic nonderivatized cellulose solution about a mandrel and through a long air gap in excess of 304 mm is facilitated by use of a mandrel which is extensible from the extrusion die. On extrusion start-up, the mandrel extends a short length from the die. For steady-state operation, the mandrel is extended its full length from the die. Also disclosed is a mandrel structure to facilitate the introduction of a nonsolvent liquid into the interior of the extruded tube at a high location on start-up of extrusion and at a lower location during steady-state operation.