Patent GB-794053-A (GB)
Title: Improvements in or relating to chromium-complexes of monoazo dyestuffs
IPC: C09B45/16
Filed: 1955-08-22
Abstract: The invention comprises dyestuffs in which chromium is complexed with radicles A and B where A is a residue of a monoazo compound free of sulphonic acid groups and of formula: <FORM:0794053/IV (b)/1> where R1 is a benzene residue, R2 is a naphthalene residue, X is OH or COOH, Y is a secondary amino group, both X and Y being oto the azo group and which contains at least one alkylsulphonyl group or sulphonamide group which may be substituted as the N atom by a lower alkyl, lower hydroxyalkyl, lower alkoxyalkyl, cycloalkyl, aralkyl, mononuclear aryl or morpholyl group, and B is the same as A or is a different monoazo compound of the same formula as A or is a residue of a monoazo compound free of sulphonic acid groups of formula R3-N = N-R4, where R3 is a benzene residue containing a COOH or OH group o to the azo group and R4 is a residue of an azo component containing a primary amino or phenolic or enolic hydroxy group o to the azo group, less than two chromium atoms being present for two molecules of monoazo compounds.  They are made by treating appropriate monoazo compounds or mixtures thereof with chromiumyielding agents in such quantities that less than 2 chromium atoms are present per mol. of final dyestuff.  Monoazo compounds corresponding to A are preferably made by acid coupling, diazo components mentioned being 2-aminophenol and its 4-halogeno, 4- and 5-nitro-, 4-alkylsulphonyl, 4- and 5-sulphonamido-, 6-halogeno - 4 - sulphonamido - and 4 - halogeno - and alkyl - 5 - and 6 - sulphonamido derivatives, anthranilic acid, 2-amino-5-alkylsulphonyl - 1 - benzoic acid and 2 - aminobenzoic acid 4- and 5-sulphonamides.  The sulphonamides may be substituted on their N-atoms by alkyl, hydroxy-, alkoxy-, cycloalkyl, aralkyl and aryl groups.  Azo components mentioned are 2-methylaminonaphthalene and its 6-alkoxy, alkylsulphonyl and sulphonamido derivatives, 1-methylaminonaphthalene-4-sulphonamide, 2-(21 - hydroxy) - ethyl -, (31 - methoxy) - propyl -, amyl-, phenyl- and (41-methyl- and chloro-) phenyl - aminonaphthalenes, phenylaminonaphthalenes being preferred. Diazo components indicated for monoazo compound B when not similar to A are those mentioned above in connection with A, the azo components indicated being phenols, naphthols, naphthylamines, pyrazolones and acetoacetylaminoalkanes and benzenes.  Chroming is effected in conventional fashion advantageously in a strongly caustic alkaline medium with the addition of reducing substances.  The dyestuffs dye wool, silk and leather from neutral or weakly acid dyebaths and also dye synthetic polyamide fibres.  Shades of brown through khaki and olive to grey are obtained.  Examples are provided illustrating the preparation of the dyestuffs and their use in dyeing nitrogenous fibres, diazo components for monoazo compound A being 2-aminophenol-4-sulphonamide and N-methyl-, 31-methoxy-propyl, amyl-, phenyl-, 41-methylphenyl-, benzyl- and cyclohexyl-sulphonamides, 2 - aminophenol - 5 - sulphonamide and its N-31-methoxypropyl derivative and 5-sulphuric acid morpholide, 2-aminophenol and its 4-methylsulphonyl and chloro-and 5-nitro-derivatives and 2-amino-4-N-41-methylphenylsulphonamido-benzoic acid with the following azo components: 2-methyl-, 21 - hydroxyethyl -, 31 - methoxy - and 21-hydroxy - propyl -, phenyl - and 31 - and 41-chloro -, 41 - methyl and methoxy -, 31-methylsulphonyl - phenyl, cyclohexyl - and benzylaminonaphthalenes, 2 - phenylaminonaphthalene - 31 - sulphonamide, 2 - methyl-aminonaphthalene - 6 - N - methyl - and 21-hydroxypropylsulphonamides, 2 - methylamino - 6 - methylsulphonylnaphthalene and 1-phenylaminonaphthalene - 4 - sulphonamide, the diazo components for b  being 2-amino-1-benzoic acid and its 4-N-methyl- and phenylsulphonamides, 2 - amino - 1 - hydroxy - 4-chloro -, sulphonamido -, N - 21 - hydroxy - and 31 - methoxy - propyl - sulphonamido - and methylsulphonyl - benzene, 2 - amino - 5-nitro - phenol, and 2 - amino - 1 - hydroxy - 4-nitro - 6 - acetylaminobenzene with the following azo components: 1 - phenyl - and 31-chlorophenyl - 3 - methyl - 5 - pyrazolones, 1-acetylamino - 7 - naphthol, 1 - acetoacetylamino - 2 - ethane, 2 - 31 - chlorophenylaminonaphthalene, 2 - aminonaphthalene and its 6-N - methylaminosulphonamide and 1 - hydroxy-2 - acetylamino - 4 - methyl - and tert. - butyl - benzenes.