Patent GB-571334-A (GB)
Title: Process for the preparation in substance or by metallisation or the like of metal-containing substantive azo dyestuffs
IPC: C09B33/26
Filed: 1942-06-17
Abstract: Azo dyes containing metal in complex union are produced in substance or on the fibre by diazotizing an aminodisazo compound, containing at least one sulphonic acid group, of the general formula <FORM:0571334/IV/1> wherein R1 represents a naphthalene residue carrying in o-position to the azo groups a hydroxyl group, an acylated or alkylated hydroxyl group or halogen, R2 represents a 1 : 4-naphthylene residue and X represents a hydroxyl group, an acylated hydroxyl group, a halogen atom or an alkoxyl group, in which last case there is no alkoxyl group in p-position thereto, which compound may already contain metal in complex union, and coupling with a component, which may contain azo groups, the product, if not containing metal in complex union, being metallised in substance or on the fibre.  The polyazo dyestuffs, if they still contain a diazotizable amino group, may be diazotized before or after the metallisation and coupled with a component in substance or on the fibre.  The products dye cotton, linen and regenerated cellulose fibres blue, grey, green and olive shades, fast to wet treatments and to light.  They are also suitable for dyeing leather.  The amino-disazo compounds are obtainable by (a) coupling an o-hydroxy-, o-alkoxy-, o-acyloxy- or o-halogen-diazonaphthalene with a 3-aminophenol or an alkyl ether thereof having a free 6-position, further diazotizing and coupling with an amine of the naphthalene series in p-position to the amino group, or (b) coupling a diazotized 4-nitro-2-hydroxy- or alkoxy-aniline or a diazotized 4 - acylamino - 2 - hydroxy-, acyloxy- or alkoxyaniline with a hydroxynaphthalene in o-position to the hydroxy group, reducing the nitro group or hydrolysing the acylamino group, diazotizing and coupling with an amine of the naphthalene series in p-position to the amino group. Specified metal-yielding agents are compounds of copper, nickel, cobalt, chromium, iron or vanadium or the metals themselves.  In examples: (1) the aminodisazo compound, 4-amino - 2 - hydroxybenzene - azo - 21 - naphthol - 41-sulphonic acid --> 1 : 6- or 1 : 7-aminonaphthalenesulphonic acid is diazotized and coupled (alkaline) with N-phenyl-2 : 5 : 7-aminonaphtholsulphonic acid or its 41-methyl- or 31-carboxy-derivative and the product treated with a warm aqueous solution of copper sulphate containing sodium acetate or ammonia; (2) the copper compound of the aminodisazo compound in (1) is diazotized and coupled (alkaline) with N-phenyl-2 : 5 : 7-acid; (3) the first component in (1) is replaced by 4-amino-2-hydroxybenzene - azo - 21 - (11 - hydroxy) - naphthalene - 41 - sulphonic acid; (4) the final component in (1) is replaced by N-acetyl - 1 : 8 : 3 : 6-aminonaphtholdisulphonic acid; (5) the final component in (1) is replaced by 2 : 5 : 7-acid; (6) the final component in (2) is replaced by the monoazo dyestuff, 4 - hydroxy - 3 - carboxy - benzene - azo - 2 : 5 : 7-aminonaphtholsulphonic acid.  A table is also given showing the colours of the dyeings obtainable on cotton with the copper compounds of the dyestuffs (1) 4-amino-5-methyl-2-hydroxybenzene - azo-21 - naphthol - 41 - sulphonic acid --> 1 : 6-aminonaphthalenesulphonic acid --> (alkaline) N-phenyl-2 : 5 : 7-acid; (2), (3), (4) and (5) 4-amino-2-hydroxybenzene-azo-2-naphthol - 4 - sulphonic acid --> 1 : 7 - amino - naphthalenesulphonic acid -->; (2) N-benzoyl-2 : 5 : 7-acid; (3) N-benzoyl-2 : 8 : 6-acid; (4) 1-(phenylazo)-2 : 5 : 7-acid; (5) 1-(21-hydroxy)-naphthylazo - 8 - hydroxynaphthalene - 3 : 6 - disulphonic acid.  The Specification as open to inspection under Sect. 91 comprises also the use as third components of amines of the benzene series coupling in p-position to the amino group, e.g. in preparing the dyestuffs, 4-amino-2-hydrocybenzeneazo - 2 - naphthol - 4 - sulphonic acid --> p - xylidine or cresidine --> N-phenyl-2 : 5 : 7-acid.  This subject-matter does not appear in the Specification as accepted.