Patent GB-995368-A (GB)
Title: Improvements relating to disazo dyestuffs and their use
IPC: C09B33/12
Filed: 1962-12-14
Abstract: Bis - [3 - (31 - methyl - 51 - amino - pyrazolyl-(11)-phenyl] sulphone is obtained by reacting 3,31 - bis - hydrazino - 1,11 - diphenyl sulphone with cyanoacetone imine.  Bis - [4 - (31 - methyl - 51 - amino - pyrazolyl-(11)-phenyl]-ketone is obtained by reacting 4,41-bis-hydrazino-1,11-diphenyl ketone with cyanoacetone imine.  Bis - [3 - (31 - methyl - 51 - amino - pyrazolyl-(11) - 4 - sulphophenyl] - sulphone is obtained by reacting 3,31-bis-hydrazine-1,11-diphenyl sulphone-4,41-disulphonic acid with cyanoacetone imine.  Bis - [3 - (31 - methyl - 51 - amino - pyrazolyl-(11) - phenyl] - disulphimide is obtained by reacting 3,31 - bis -hydrazino - 1,11 - diphenyl disulphimide with cyanoacetone imine.ALSO:The invention comprises disazo dyes containing at least one water solubilizing group which dissociate acidically in water of the formula <FORM:0995368/C4-C5/1> wherein A represents the carbonyl, sulphonyl or the disulphimide group, Y represents an unsubstituted benzene ring or a benzene ring which may be further substituted and D represents a negatively substituted radical of the benzene series which may contain other substituents usual in azo dyes.  Negative substituents in D are trifluoromethyl and cyano groups and are trifluoromethyl and cyano groups and substituents which contain an oxygen atom and of which the bond between the linking atom and oxygen is semipolar, namely the nitro, carboxy, alkyl and aryl carbonyl, carboxylic acid ester, carboxylic acid amide alkyl and aryl sulphoxyl groups as well as in a preferred group of dyes the sulphonyl containing group of the formula -SO2R in which R is hydroxyl or optionally substituted alkyl, aryl, aryloxy, amino or acylamino, such as the sulphonic acid group, alkyl or aryl sulphonyl groups, sulphonic acid aryl ester groups and sulphonic acid amide groups optionally substituted at the nitrogen atom by one or two groups, sulphonic acid aryl ester groups and sulphonic acid amide groups optionally substituted at the nitrogen atom by one or two aliphatic, aromatic or heterocyclic radicals and acylated sulphonic acid amide groups having an acyl radical derived from aliphatic or aromatic carboxylic or sulphonic acids. The dyes are prepared by diazotizing an appropriate benzene series amine and (a) coupling with a coupling component of the formula <FORM:0995368/C4-C5/2> or (b) coupling with a compound of the formula <FORM:0995368/C4-C5/3> where M represents the oxo or imino group to form a monoazo dye of the formula <FORM:0995368/C4-C5/4> and condensing two mols. thereof with one mol. <FORM:0995368/C4-C5/5> the coupling and diazo components being chosen so that the disazo dye contains at least one water solubilizing group which dissociates acidically in water.  Representative of the diazo components employed in examples are 4-amino - diphenyl ether - 3 - sulphonic acid, 3-aminobenzene - 1 - sulphonic acid - N - ethyl-N - 41 - sulphophenylamide, 2 - amino - 1,11-diphenyl sulphone - 31 - sulphonic acid, 2-amino - 41 - methyl - 11,1 - diphenylsulphimide, 2 - aminobenzene - 1 - sulphonic acid phenyl ester 2 - amino - 5 - chloracetylaminobenzene-1 - sulphonic acid (21 - methylphenyl) ester, 2-amino - 5 - nitrobenzene - 1 - sulphonic acid. The dyes are usually isolated as ammonium or alkali metal salts and are suitable for dyeing leather, silk, wool, synthetic polyamide and polyurethane fibres.