Patent GB-360449-A (GB)
Title: Improvements in or relating to the colouration of textile materials
Filed: 1930-07-02
Abstract: Cellulose esters or ethers, dyeing; vat dyes, dyeing with; regenerated celluloses; dyeing.--Textile materials made of or containing cellulose esters or ethers are dyed by the application of vat dyestuffs from vats containing inorganic alkali only and of an alkalinity not exceeding 2 grs. per litre of Na2CO3 and containing an amount of hydrosulphite not less than 3 times the weight of the dyestuff present.  The following examples are specified.  (1) A scoured cellulose acetate fabric is dyed green shades, very fast to light, by treatment for 1 hour at 75 DEG  C. in a 40 : 1 bath containing 5 per cent (based on weight of fabric) of Anthrene jade green, 5 to 10 grs. per litre of hydrosulphite, and 0,5 grs. per litre of soda ash, followed by treatment for about 15 minutes at 60 DEG  C. in an oxidizing solution containing 2 grs. per litre of sodium perborate.  (2) A fabric containing cellulose acetate is similarly dyed greenish blue shades, fast to light and washing, with Anthrene blue green B.  (3) A cellulose acetate fabric is similarly dyed violet shades, fast to light and washing, with Ponsol violet RRD.  (4) A scoured cellulose propionate fabric is similarly dyed with Anthrene jade green.  (5) A cellulose acetate fabric is dyed greenish yellow shades, fast to light, by treatment for \ba1/2\be hour at 75 DEG  C. in a 40 : 1 bath containing 7 per cent of Ciba yellow G, 10 grs. per litre of hydrosulphite and 2 grs. per litre of soda ash, followed by treatment for about 15 minutes at 60 DEG  C. in an oxidizing solution containing 2 grs. per litre of sodium perborate.  (6) A scoured cellulose acetate fabric is dyed pure yellow shades, fast to light and washing, with the dyestuff Ciba yellow G by a process corresponding to that of (1) above.  (7) A fabric containing cellulose acetate is dyed gooseberry shades, fast to washing and light, by treatment for \ba1/2\be to 1 hour at 75 DEG C. in a 40 : 1 bath containing 3 per cent of Anthrene blue green B, 4 per cent of Ciba yellow G, 0,5 per cent of Ponsol violet RRD, 10 grs. per litre of hydrosulphite and 0,5 grs. per litre of soda ash, followed by treatment for 15 minutes at 60 DEG  C. in an oxidizing solution containing 2 grs. per litre of sodium perborate.  (8) A fabric containing cellulose acetate is similarly dyed sky blue shades, fast to light, by the use as dyestuffs of 1 per cent of Anthrene blue green B and 0,2 per cent of Ponsol violet RRD. Other vat dyes specified as suitable are Ciba blue G, Algol yellow R, Anthrene brown BB and Ponsol green BN.  The invention is applicable also for dyeing fabrics containing, in addition to cellulose ester or ether fibres, wool, silk, cotton, or regenerated cellulose fibres, and for dyeing fabrics made of or containing partially saponified cellulose esters.  The Specification as open to inspection under Sect. 91 (3) (a) comprises also a further example in which a methylcellulose fabric is dyed with Anthrene blue green B by a process corresponding to that of (1) above employing 2 grs. per litre of soda ash.  Newport Indanthrene direct black RB is also specified as a suitable vat dyestuff.  This subjectmatter does not appear in the Specification as accepted.