The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 11, 1983
Filed:
Jun. 06, 1980
Gianfranco Angelini, Buscate, IT;
Ugo Paoletti, Monza, IT;
Abstract
A process for the xanthation of alkali-cellulose comprises the reaction of he alkali-cellulose with CS.sub.2 in excess with respect to the desired xanthate substitution degree at a pressure which increases from the initial 110 mm Hg to about 400-500 mm Hg and at a temperature increasing from about 21.degree. C. to about 23.degree.-25.degree. C. The unreacted CS.sub.2 is removed from the reactor, once the desired xanthate substitution degree is reached, by application of a vacuum. This viscose rayon continuous spinning process eliminates the need for the usual desulphuration phase for decreasing the sulphur content and for bleaching the product. The viscose obtained has reduced content of compounds capable of forming elementary sulphur. The regenerated cellulose yarn has improved characteristics as to the sulphur content and degree of whiteness.