Patent GB-416779-A (GB)
Title: New azo dyestuffs and application thereof
IPC: C09B29/20
Filed: 1933-02-14
Abstract: Azo dyes; azo dyes, forming upon the material; acid wool dyes and substantive dyes, dyeing with. --Azo dyes are manufactured by diazotizing a compound containing the grouping <FORM:0416779/IV/1> where Ar is an aromatic residue of the benzene series carrying a diazotizable amino-group, X is --S-- or --O--, Y is --CH2--, --CH Alkyl-- or --C(Alkyl)2, and Z is a group (such as NO2) which is readily convertible into an amino group, Z being in the o-position to the grouping --X--Y--COOH, and coupling the diazo compound with a 2 : 3-hydroxynaphthoic arylamide containing the same or a different grouping <FORM:0416779/IV/2> where Ar is an aromatic residue of the benzene series contained in the arylamide grouping, X, Y and Z have the above significance, and Z may also be NH2, the group or groups Z being converted, if necessary, into amino groups at a suitable stage in the manufacture, the carboxylic groups being present as such or, if desired, in the form of alkyl ester groups which are subsequently hydrolysed, and both the components being free from water-solubilizing groups other than the carboxyl groups in the above formul .  Textile materials are dyed by applying the products from neutral or acetic acid baths or by forming them on the fibre, the dyeings being lactamized by treatment with dilute mineral acid.  When forming the dyestuff on the fibre, the coupling component may be lactamized on the fibre before coupling. In examples: (1) 2-nitro-4-aminophenylthioglycollic acid is diazotized and coupled with 2 - amino - 4 - (2<1> : 3<1> - hydroxynaphthoylamino) - phenylthioglycollic acid and the product is reduced with sodium sulphide solution; (2) wool or silk is dyed red with the product of (1) in the presence of acetic acid, the dyeing being lactamized by means of dilute mineral acid, e.g. N/10 hydrochloric acid; (3) 2 - nitro - 4 - aminophenylthioglycollic acid is diazotized and coupled with the p-thioglycollic acid of the m-aminobenzoyl-m-aminoanilide of 2 : 3-hydroxynaphthoic acid and the product is reduced with sodium sulphide; (4) wool or silk is dyed bluish red with the product of (3) by a process similar to that of (2); (5) 2-nitro-4-aminophenyllactic acid is diazotized and coupled with the sodium salt of 5-(2<1> : 3<1>-hydroxynaphthoylamino) - 4 - chloro - 2 - aminophenylthioglycollic acid and the product is reduced with sodium sulphide; (6) wool is dyed red with the product of (5) in the presence of ammonium acetate, the dyeing being lactamized; (7) 2-nitro-4-methyl-5-aminophenylthioglycollic acid is diazotized and coupled with the product obtained by reducing 2-nitro-5- (2<1> : 3<1>-hydroxynaphthoylamino) - phenylthioglycollic acid with ferrous sulphate, and the product is reduced with sodium sulphide; (8) wool is dyed bordeaux with the product of (7) by a process similar to that of (6); (9) 2 : nitro-5-amino-4-methoxyphenylthiolactic acid is diazotized and coupled with 2-nitro-5-(2<1> : 3<1>-hydroxynaphthoylamino)-phenylthioglycollic acid and the product is reduced with sodium sulphide; (10) wool is dyed violet with the product of (9) by a process similar to that of (6); (11) 2-nitro-4-aminophenylglycollic acid is diazotized and coupled with the methyl ester of 2-nitro-4-(2<1> : 3<1> - hydroxynaphthoylamino) - phenylglycollate, and the product is reduced and hydrolyzed by means of sodium sulphide; (12) wool is dyed red with the product of (11) by a process similar to that of (6); (13) 2-nitro-4-methyl-5-aminophenylthioglycollic acid is diazotized and coupled with the sodium salt of 2-amino-4-(2<1> : 3<1> - hydroxynaphthoylamino) - phenylthiolactic acid and the product is reduced with sodium sulphide; (14) wool or silk is dyed bordeaux with the product of (13) by a process similar to that of (6); (15) the diazo-component of (13) is replaced by 2-nitro-5-amino-4-methoxyphenylthiolactic acid; (16) the product of (16) yields violet shades; (17) the coupling component of (11) is replaced by 2-nitro-5-(2<1> : 3<1> - hydroxynaphthoylamino)-4-methoxyphenylthioglycollic acid; (18) the product of (17) yields a red shade; (19) 2-nitro-5-amino-4-methoxyphenylthiolactic acid is diazotized and coupled with the p-thioglycollic acid of 2 : 3-hydroxynaphthoic - m - aminoanilide and the product is reduced; (20) wool or silk is dyed violet with the product of (19); (21) wool or silk is impregnated with the sodium salt of 2 - amino - 4 - (2<1> : 3<1> - hydroxynaphthoylamino) - phenylglycollic acid which is coupled on the fibre with diazotized 2-nitro-4-aminophenylthioglycollic acid and the dyeing is lactamized, producing a red shade.  Specifications 377,739, 406,281, 415,753, and 416,778 are referred to.  2 - Nitro - 5 - amino - 4 - methoxyphenylthiolactic acid is obtained by nitrating 4-chloro-o-acetanisidide, hydrolysing the acetylamino group and condensing with thiolactic acid.