Process for the continuous spinning of viscose rayon
AssigneeSnia Viscosa Societa' Nazionale Industria Applicazioni Viscosa S.p.A.
InventorsTommaso Benai, Ugo Paoletti, Novello Leoncini
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AssigneeSnia Viscosa Societa' Nazionale Industria Applicazioni Viscosa S.p.A.
InventorsTommaso Benai, Ugo Paoletti, Novello Leoncini
Estimating the term…
A process is provided herein for continuously spinning viscose yarns by euding viscose into a coagulating bath to form filaments and partially coagulating these filaments to a coagulation index of between 15 and 18, while concurrently stretching said filaments to the desired stretch ratio and then subjecting the filaments to a 2-stage coagulation treatment in which (1) the filaments are advanced without further chemical treatment onto e.g. a first advancing roller where partial spontaneous coagulation occurs such that the coagulation index is between 5 and 8 and (2) a second stage coagulation which comprises contacting the filaments with an acid bath at a temperature between 50.degree. and 100.degree. C. until complete coagulation occurs such that the coagulation index is between 0 and 1. The aforementioned process permits the spinning operation to occur at a much greater speed than was hitherto possible without increasing dimensions of the treatment zones or apparatus.
A process of continuously spinning viscose rayon yarns, comprising the steps of extruding said viscose into a coagulating bath to form filaments having a coagulation index of between 15 and 18 and concurrently stretching said filaments to the desired final stretch ratio and then subjecting the filaments to a two-stage coagulation treatment without any further stretching;
Dependencies are inferred from the claim text.