Method of manufacture of regenerated cellulose free of spots, which is transparent and colored pigment with a colouring of the vessel and regenerated cellulose prepared by this process

摘要

1,012,079. Making coloured transparent regenerated cellulose films and filaments. ALLIED CHEMICAL CORPORATION. May 12, 1964 [July 8, 1963], No. 19766/64. Heading B5B. Coloured, transparent speck-free regenerated cellulose films, filaments &c. are made by shaping a mixture of viscose and an aqueous dispersion of a vat dye, the particles of which do not exceed 1 micron in their largest dimension, into a film or filament &c. which is contacted with a coagulating and regenerating bath. The bath may be a dilute aqueous solution of sulphuric acid. The ratio of viscose to vat pigment may range from 100: 1 to 100,000: 1 by weight. The vat dye may be N,NSP1/SP- bis - (p - methoxyphenyl) - 3,4,9,10-perylene tetra-carboxylic diimide, indigo, Flavanthrone, or a polybrominated pyranthrone.