摘要 |
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 characterised in that an extrusion die is used which has an extrusion gap b of 220 mum<=b<=280 mum. Moreover, the invention relates to flat films, obtainable by the amine oxide process with a thickness d of less than 20 mum, 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 mum and whereby MD stands for the tenacity of the film in the longitudinal direction (N/mm2) and TD for the tenacity of the film in the transverse direction (N/mm2).
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