Process for recycling colored, cellulosic waste products into fibers

摘要

In the prodn. of viscose, (a) cellulose material (I) dyed with reactive dyes, opt. mixed with pulp, is suspended in aq. alkali soln. (alkali cellulose); (b) opt. treated with a reducing S cpd. at 20-80 degrees C; (c) allowed to ripen for at least 30 min. at 30-80 degrees C; (d) brought into soln. as xanthate by reacting the alkali cellulose with CS2 at 10-30 degrees C; and (e) spun to fibres or converted to film. Also claimed are coloured or white viscose fibres and films prepd. in this way.