GB532113A - Improvements in or relating to the dyeing of textile materials comprising cellulose derivatives - Google Patents

Abstract

532,113. Dyeing textiles; artificial silk. COURTAULDS, Ltd., and PAUL, H. June 16, 1939, No. 17653. [Classes 2 (ii), 2 (iii) and 15 (ii)] Textile materials made of or containing an aliphatic carboxylic acid ester of cellulose are coloured by incorporating therein a free aliphatic diamine containing less than 7 carbon atoms and thereafter, without substantial removal of the diamine, dyeing with an acid wool dyestuff. Specified diamines are ethylene diamine, 1:2- diaminopropane and hexamethylene diamine. The materials may be treated, before the dyeing operation, with a compound such as formaldehyde, carbon disulphide, or carbon oxysulphide, which forms an insoluble condensation product with the diamine. Heating to effect a complete condensation may be necessary. The use, as described in Specification 499,868, of acid dyestuffs containing one or more residues, such as halogen or a nitro group, capable of splitting off acid by reaction with amino groups in the material, is excluded. In examples, (1) hexamethylene diamine is incorporated in a solution of cellulose acetate in acetone, the solution is extruded into air at 60-65‹C., the resulting thread is exposed to formaldehyde vapour at room temperature and dyed with Azo geranine 2GS from a dilute sulphuric acid bath at 70‹C. (2) a hank of cellulose acetate yarn is padded in a cold aqueous solution of ethylenediamine, dried at 70‹ C., heated for 15 minutes at 120‹C. and dyed with Coomassie yellow RS or Elite F yellow 2GrS from a dilute acetic acid bath at 80‹C., (3) a hank of cellulose acetate yarn is padded and further treated as in (2) with an addition of formaldehyde to the padding solution ; the dyestuff may be replaced by Solway blue BHS, Azo geranine 2GS, Coomassie red SPG or Coomassie navy blue 2RNS.