Patent ID: 6656547
Filing Date: 2003-12-02
Classification: A22C,B29C,Y10T

Abstract:
A seamless tubular cellulose-based film obtained by extruding a spinning solution containing cellulose-, N-methylmorpholine N-oxide-, and water through an annular die and treating the tubular film in an N-methylmorpholine N-oxide-containing aqueous spinning bath, the film being transversely stretched by blow molding in an air section between the annular gap and surface of the spinning bath, wherein the spinning solution comprises 0.2 to 50% by weight, based on the weight of the cellulose, of one or more modifying compounds which increase the suppleness, strength, clipping stability and shear stability of the tubular casing and which are miscible with said spinning solution, wherein the modifying compound comprises a hydrophilic naturally occurring polymer, a hydrophilic synthetic polymer, a polymer which simultaneously possesses hydrophilic and hydrophobic properties, or a polyethyleneimine.