Verfahren zum Herstellen eines Vliesstoffes und nach dem Verfahren hergestellter Vliesstoff

摘要

1329615 Hydroxymethyl cellulose xanthate fibres MITSUBISHI RAYON CO Ltd 1 Sept 1970 [12 Sept 1969 13 Sept 1969 27 Feb 1970] 41728/70 Heading B5B [Also in Divisions D1-D2] Hydroxymethyl cellulose xanthate fibres are made by extruding viscose into a coagulant bath containing formaldehyde, stretching the extruded filaments, and cutting the filaments. The viscose used preferably contains 2-8% by wt. of total alkali and has a salt point of at least 6. Gas-generating materials and flame proofing agents may be incorporated in the viscose. The coagulation bath may contain sodium sulphate, zinc sulphate, and sulphuric acid in addition to formaldehyde, and optionally surface-active agents. The hydroxymethyl cellulose xanthate fibres may be swollen prior to web-formation by treatment with (a) substantially salt-free aqueous acidic solutions having a pH higher than 2, (b) aqueous inorganic and/or organic salt solutions, and (c) aqueous solutions of organic solvents. The fibres may be crimped by the treatment with the swelling agents. The fibres may also be prepared by the addition of formaldehyde to the viscose before it is coagulated, and also by treatment of coagulated viscose filaments with formaldehyde.