Process for the production of cellulosic fibres
AssigneeLenzing Aktiengesellschaft
InventorsWilhelm Feilmair, Heinrich Firgo, Johann Männer
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Abstract
The invention relates to a process for the production of cellulosic fibers from solutions of cellulose in an aqueous tertiary amine oxide whereby the extruded fibers are led through a precipitating bath and cut and the cut fibers are passed through a series of water baths in the form of a fleece and then dried, whereby the wash baths are connected to each other and fresh washing liquor is applied to the last wash bath and led in countercurrent with the transportation direction of the fibre fleece to the first wash bath. The process in accordance with the invention is characterised in that the pH value of each of these wash baths is maintained higher than 8.5.
Claims13
A process for the production of cellulosic fibres from solutions of cellulose in an aqueous tertiary amine oxide comprising (i) extruding cellulosic fibres;
- (ii) leading the fibres through a precipitating bath;
- (iii) cutting the fibres to form a fleece;
- (iv) passing the fleece through a series of wash baths, wherein (a) the wash baths are connected one to the other, (b) fresh washing liquor is applied to the last wash bath and led in countercurrent with the transportation direction of the fleece;
- and (c) the pH value of each of said wash baths is maintained higher than 8.5;
- and (v) drying the washed fleece.
Dependencies are inferred from the claim text.