Patent GB-599867-A (GB)
Title: Manufacture of azo-dyestuffs capable of being chromed
Filed: 1945-09-19
Abstract: Azy dyestuffs are manufactured by coupling a diazotized aromatic amine containing a lake-forming group, in an alkaline medium, advantageously in the presence of pyridine, with a coupling component of the general formula <FORM:0599867/IV/1> wherein X represents an SO2 or CO group and Z an aliphatic, aromatic or hydroaromatic residue.  The products may be treated in substance or on the fibre with an agent yielding yielding chromium.  Suitable diazo components are amines containing a hydroxy, carboxyl or alkoxy group in o-position to the amino group or containing a salicylic acid grouping, e.g. o-aminophenols, o-aminonaphthols, o-aminobenzoic acids, o-aminonaphthalene carboxylic acids, o-amino-alkoxy- (e.g. -methoxy-, -ethoxy- or -propyloxy-) benzenes and aminosalicylic acids, which amines may contain further substituents, e.g. alkyl, nitro or sulphonic acid groups or halogen atoms.  In examples: (1) 2-aminophenol-4-sulphonic acid is diazotized and coupled with 1-hydroxy-naphthalene-4 - (41 - methylphenyl) - sulphone-8-sulphonic acid; the product dyes wool from an acid bath in red shades becoming Bordeaux red on after-chroming; the coupling components may be replaced by the 4-methylsulphone, yielding a somewhat more yellowish dyestuff; (2) 2-aminobenzoic acid or its 4- or 5-methyl derivative is diazotized and coupled with 1-hydroxynaphthalene-4-methyl ketone-8-sulphonic acid and the product is boiled with a solution of ammonium chromo-salicylate; the products dye wool from a formic acid bath in wine-red shades; (3) 4 : 6-dichloro-2-aminophenol is diazotized and coupled with 1-hydroxynaphthalene-4-phenyl ketone-8-sulphonic acid; the product dyes wool in violet shades by the single bath chroming process; (4) 4-chloro-2-aminophenol-6-sulphonic acid is diazotized and coupled with 1-hydroxynaphthalene - 4 - methyl ketone - 8 - sulphonic acid, and the product is refluxed with a solution of basic chromium sulphate; the product dyes wool from a strong sulphuric acid bath in violet shades; (5) 5-nitro-2-aminophenol is diazotized and coupled with 1-hydroxynaphthalene - 4 - (21 : 41 - dichlorophenyl) - ketone - 8 - sulphonic acid; the product dyes wool navy blue shades by the single bath chroming process; (6) 5-nitro-4-methyl-2-aminophenol is diazotized and coupled with the disodium salt of 1 - hydroxynaphthalene - 4 - methyl ketone-8-sulphonic acid, and the product is boiled with a solution of ammonium chromo-salicylate; the product dyes wool from a formic acid bath in reddish blue shades (7) 4-chloro-5-nitro-2-aminophenol is diazotized and coupled with the monosodium salt of 1-hydroxynaphthalene-4-hexahydrophenyl ketone-8-sulphonic acid; the product dyes wool from an acid bath in Bordeaux red shades becoming blue on after-chroming; (8) 5-nitro-2-aminophenol is diazotized and coupled with 1-hydroxynaphthalene - 4 - (41 - aminophenyl) - ketone - 8 - sulphonic acid; the product dyes wool from an acid bath in wine-red shades becoming grey on after-chroming; (9) diazotized 1-amino-2-hydroxynaphthalene-4-sulphonic acid is coupled with the potassium salt of 1-hydroxynaphthalene - 4 - methyl ketone - 8 - sulphonic acid, and the product is refluxed with a solution of chromic sulphate; the product dyes wool from a strong sulphuric acid bath in blue shades - the coupling component may be replaced by the 4-phenyl ketone, yielding a more greenish dyestuff; (10) 1-amino-2-hydroxynaphthalene; 4-sulphonic acid is diazotized and coupled with 1 - hydroxynaphthalene - 4 - (41 - aminophenyl)-ketone-8-sulphonic acid; the product dyes wool in bluish olive shades by the after-chroming process; the coupling component may be replaced by the 31-aminophenyl ketone, the product yielding a duller and redder shade.  Specifications 15,025/04, [Class 2], 26,460/12, [Class 1 (iii)], and 575,285 are referred to.