process for faerben of regenerated cellulose in gleichmaessigen toenen

摘要

294,922. British Dyestuffs Corporation, Ltd., Baddiley, J., Chorley, P., and Brightman, R. April 28, 1927. Disazo dyes are obtained by coupling tetrazotized 2-nitro- or 2 : 21-dinitrobenzidine with two molecular proportions of a 2 : 8-aminonaphthol sulphonic acid or an N-derivative thereof or with one molecular proportion of such acid or derivative and one molecular proportion of any coupling component. The products in some cases yield even dyeings on regenerated cellulose silk, and in some cases yield dyeings fast to milling on wool. The following examples are specified :- (1) a dyestuff yielding red shades on viscose silk and wool is obtained by coupling 1 mol. of tetrazotized 2-nitrobenzidine with 1 mol. of salicylic acid (alkaline coupling) and 1 mol. of 2 : 8 . 6-acid (acid coupling); (2) a dyestuff yielding yellow-brown shades on viscose silk and wool is obtained by coupling 1 mol. of tetrazotized 2- nitrobenzidine with 1 mol. of 1-(21 : 51-dichloro- 4-sulpho) phenyl-3-methyl-5-pyrazolone (neutral coupling), and 1 mol. of 2: 8: 6-acid (alkaline coupling), and a dyestuff yielding redder shades is obtained from the same tetrazo compound with 2: 8: 6-acid and 1-(41-sulpho) phenyl-3-methyl-5- pyrazolone ; (3) a dyestuff yielding maroon shades on viscose silk and copper-brown shades on wool is obtained by coupling 1 mol. of tetrazotized 2- nitrobenzidine with 1 mol. of naphthionic acid (faintly acid coupling) and 1 mol. of phenyl- 2 : 8 : 6-acid (alkaline coupling) ; (4) a dyestuff yielding violet-brown shades on viscose silk and wool is obtained by coupling 1 mol. of tetrazotized 2-nitrobenzidine with 1 mol. of 2:8:6- acid (alkaline coupling) and 1 mol. of resorcinol or m-phenylenediamine, a dyestuff yielding violet shades on viscose silk and wool by replacing the second coupling component by 1 : 4-naphtholsulphonic acid, and a dyestuff yielding claret shades on viscose silk and reddish-brown shades on wool by coupling the tetrazo compound with 2 mols. of 2 : 8 : 6-acid; (5) a dyestuff vielding yellow-brown shades on viscose silk is obtained by coupling 1 mol. of tetrazotized 2 : 21-dinitrobenzidine with 1 mol. of salicyclic acid (alkaline coupling) and 1 mol. of 2 : 8 : 6-acid (alkaline coupling). A table is also given showing the shades on viscose silk with dyestuffs from tetrazotized 2-nitrobenzidine and various pairs of coupling components, other specified components being o- and p-cresotinic acids. 2 : 3-oxynaphthoic acid, benzoyl-2 : 8 : 6-acid, the glycine of 2 : 8 : 6- acid, ethyl-2: 8 : 6-acid. 21 : 4'-dinitrophenyl- 2 : 8 : 6-acid, 41-chlorophenyl-2 : 8 : 6-acid, and m-xylyl-2 : 8 : 6-acid. 2-(41-chlorophenyl)amino-8-naphthol-6-sulphonic acid is obtained by condensing p-chloraniline with 2 : 8 : 6-acid in presence of bisulphite.