GB416053A - Improvements in the manufacture and production of disazo dyestuffs - Google Patents

Abstract

Disazo dyes are made by coupling tetrazotized 4 : 4<1>-diaminobenzophenone or its derivatives with a hydroxynaphthalene containing the group --NHSO2-- or --NHCO-- which is connected with an aryl radicle either through the nitrogen atom, cf. Specifications 211,223 and 263,164, [both in Class 2 (iii)], or through the sulphur or carbon atom, alone or together with another coupling component, the components being so chosen that there is at least one sulphonic acid group in the finished dyestuff. Suitable coupling components are 2 : 3-oxynaphthoic arylides, hydroxynaphthalenesulpharylides, benzoylaminonaphthols, benzoyl- or arylsulphaminonaphtholsulphonic acids and sulphonic acids of 2 : 3-oxynaphthoic arylides. The alkyl, alkoxy, nitro, sulpho, halogen and carboxy derivatives of 4 : 4<1>-diaminobenzophenone are specified. The dyestuffs yield on wool and silk brilliant dyeings of good fastness to light and excellent fastness to washing, fulling and water. In examples, the following dyestuffs are described: (1) 4 : 4<1>-diaminobenzophenone \sQ N-benzoyl H acid, N-benzoyl J acid, N-benzoyl K acid (1 mol.), and b -naphthol (1 mol.), N-2<1> : 5<1>-dichlorbenzoyl K acid (1 mol.) and 2-naphthol-6-sulphonic acid (1 mol.), sulphonated 2 : 3-oxynaphthoic acid, N-benzoyl-H acid (1 mol.) and 2-naphthol-6-sulphanilide (1 mol.); (2) 3 : 3<1>-dimethoxy-4 : 4<1>-diaminobenzophenone \sQ N-benzoyl-K acid (2 mols.) or N-benzoyl-2 : 8 : 6-acid (1 mol.) and N-2<1> : 5<1>-dichlorbenzoyl-K acid (1 mol.); (3) 3 : 3<1>-dichlor-4 : 4<1>-diaminobenzophenone \sQ N-p-toluenesulpho-H acid (1 mol.) and 2 : 8 : 6-acid (1 mol.).