Patent GB-736166-A (GB)
Title: Improvements relating to copperable disazo dyestuffs and their use
IPC: C09B33/153
Filed: 1953-05-08
Abstract: The invention comprises copperable disazo dyestuffs of formula <FORM:0736166/IV (c)/1> where A is a benzene or naphthalene residue containing at least one acid water solubilizing group, B is a benzene or naphthalene residue containing a carboxy group in o-position to the azo group, and D is an unsulphonated 4,41-diphenyl radicle which may be 3,31-substituted.  They may be made by coupling in any order one mol. of an unsulphonated 4,41-di-acetoacetylamino-diphenyl compound optionally 3,31-substituted with 1 mol. of a diazonium compound of formula <FORM:0736166/IV (c)/2> and with 1 mol. of an o-carboxy-diazonium compound of the benzene or naphthalene series which may be the same as the first diazonium compound.  Specified diphenyls are 4,41-diacetoacetylamino-diphenyl optionally substituted in the 3,31-position by low alkyl and alkoxy groups or by halogens, e.g. 3,31-dimethyl-, -dimethoxy- and -dichloro-4-,41-diacetoacetylamino-diphenyl.  The diazo components of the above formula may be derived from 1 mol. of 5-amino-2-acetylaminobenzene-1-carboxylic acid and 1 mol. of a primary amino compound corresponding to A and which contains at least one sulphonic acid or carboxyl group and in addition may contain halogen, alkyl, alkoxy or hydroxyl groups or heterocyclic radicles. They may be made by treating the aqueous solution of the alkali metal salts either with phosgene until the primary amino groups have disappeared or by acylating first one of the components, preferably that corresponding to A, with a chloroformic acid phenol ester and treating the other component in aqueous solution of the alkali metal salts with the arylcarbamic acid phenol ester so obtained until the unsymmetrical urea derivative is formed by eliminating phenol and in each case the acetylamino group is finally saponified under mild conditions. The sym.-urea derivatives obtained by the first method may be removed after saponification of the acetylamino groups with dilute mineral acids because of the different solubility of the alkali metal salts in water.  Specified compounds corresponding to A are 3- or 4-aminobenzene-1-sulphonic or carboxylic acids, 2-methoxy-, -chloro- or -methyl - 5 - aminobenzene - 1 - sulphonic acids, 4-chloro- or -methyl-5-aminobenzene-1-sulphonic acids, 5-amino-2-hydroxy-benzene-1-carboxylic acid, 5-amino-3-methyl or -3-sulpho-2 - hydroxybenzene - 1 - carboxylic acids, 1-aminonaphthalene-4-sulphonic acid, 2-amino naphthalene-4,8- or -6,8-disulphonic acids, 2-(41 - aminophenyl) - 6 - methyl - benzothiazole-5- or 7-sulphonic acids.  The same or a different o-aminocarboxylic acid of the benzene or naphthalene series may be used as second diazo component, those specified being 2-aminobenzene - 1 - carboxylic acid, 2 - aminobenzene-1,4- or -1,5-dicarboxylic acid, 2-amino-1-carboxybenzene-4- or -5-sulphonic acid and corresponding sulphonic acid amides, -dimethylamides and -ethanolamides, 1-aminonaphthalene-2-carboxylic acid, 2-aminonaphthalene-3-carboxylic acid and particularly 5-acetylamino-, -carbomethoxyamino-, -carboethoxyamino- and -carbomethoxy-ethoxyamino-2-aminobenzoic acid.  The diazo components are advantageously diazotized by the gradual addition of an aqueous solution of alkali metal salts containing alkali metal nitrites to dilute acid.  Coupling is effected in neutral or alkaline media. Unsymmetrical disazo dyestuffs are produced in steps, preferably the first diazo component coupled leads to a more easily water-soluble intermediate.  The dyestuffs are coppered in the dyebath or in a fresh bath in conventional fashion in a neutral or weakly acid medium.  Before and after coppering cellulose fibres are dyed in yellow to greenish-yellow tints. Examples are provided showing the use of certain of the above reactants, additional specified compounds corresponding to A being 2-amino-benzene-1,4-disulphonic acid, 2-methyl- and -chloro-3-aminobenzene-1-sulphonic acid, 2,4-dimethyl-6-aminobenzene-1-sulphonic acid, 2-hydroxy-5-aminobenzene-1-sulphonic acid and 1-aminonaphthalene-3,8-disulphonic acid and additional specified o-amino-carboxylic acids are 4-acetyl-, -carbomethoxy-, -carboethoxy-, -carbomethoxyethoxy- and 4 and 5-carboethoxyethoxyamino - 2 - aminobenzoic acid, 5 - succinylamino - 2 - aminobenzoic acid, 2 - aminobenzoic acid-5-sulphonic acid methylamide and 4 or 5-methylsulphonyl-2-aminobenzoic acid. Specification 647,103 is referred to.