Patent GB-880021-A (GB)
Title: Improvements in or relating to photographic azo dye developers and the manufacture thereof
IPC: G03C7/30
Filed: 1958-05-19
Abstract: 880,021. Azo dye photographic developers. INTERNATIONAL POLAROID CORPORATION. May 19, 1958 [June 6, 1957 (2)], No. 16018/58. Class 2 (4). [Also in Groups IV(b) and XX.] The invention comprises a compound of formula where X<SP>2</SP> is a coupling component residue, a Y - S - R - Ar<SP>1</SP> - (Z<SP>1</SP>) p  radical or a Y-S-Ar<SP>1</SP>-(Z<SP>1</SP>)n radical, X<SP>3</SP> is a coupling component residue or a Y-S-Ar<SP>1</SP>-(Z<SP>2</SP>) n  radical, Y is a 2,5-dihydroxyphenyl group or an alkyl or halogen substituted derivative thereof, R is an alkylene group, Z<SP>1</SP> is alkyl or halogen, Z<SP>2</SP> is alkyl, alkoxy or halogen, n is 0, 1 or 2, Ar is an aryl nucleus, m is 0 or 1 and X<SP>1</SP> is a coupling component residue. They are made by diazotising compounds of formula (Z<SP>1</SP>) n -Ar (NH 2 )- R - S - Y<SP>1</SP>, (Z<SP>2</SP>) n  - Ar (NH 2 ) - S - Y<SP>1</SP>, Y<SP>1</SP>-S-R-Ar (Z<SP>1</SP>) n -N=N-X<SP>1</SP>-NH<SP>2</SP> and Y<SP>1</SP>-S-Ar (Z<SP>2</SP>) n -N=N-X<SP>1</SP>-NH 2  and coupling, preferably at a pH of not above 9, with an appropriate component. The hydroxy groups in Y<SP>1</SP> of the coupling component are protected, e.g. by acylation, before coupling is effected and liberated at the end of the reaction. Alternatively compounds of formula HS-R-Ar (Z<SP>1</SP>) n -N= N-X<SP>1</SP>(-N=N-X<SP>2</SP>) m  or HS-Ar (Z<SP>2</SP>) n -N= N-X<SP>1</SP>(-N=N-X<SP>3</SP>) n  may be reacted with appropriate p-benzoquinones. R preferably contains no more than 5 carbon atoms and the ethylene radical is especially preferred. When alkyl groups Z<SP>1</SP> and Z<SP>2</SP> are present they are preferably of low molecular weight. Preferred classes of compounds are those of formula Indicated coupling components are phenols, naphthols, aminonaphthols, anthrols, anilines, naphthylamines, pyrroles, pyrozolones and aliphatic and alicyclic compounds containing methylene groups activated by adjacent keto, aldehyde, ester or nitrile groups, or a keto, aldehyde, ester or nitrile group in combination with an amide group. Groups which may be present in the coupling components include alkyl, sulpho, alkoxy, aryl, aryloxy, keto, amino, alkylamino, arylamino, hydroxyl, cyano, alkylamide, arylamide, carbalkoxy, carboxamide and sulphonamide. Illustrative of specified coupling components are 4-benzyl-1-naphthol, 4-methoxy- 1- naphthylamine, phenol, aniline, 1,5-naphthalene diamine, 2 - hydroxyanthracene, 1 - hydroxy - 2-naphthanilide, diketohydrindene, malononitrile, aceto - acetanilide, 1 - phenyl - 3 - acetamido - 5-pyrazolone, p-naphthol, 4-sulpho-1-naphthol and 2-[α-cyanoacetyl]- conmarone. Particularly preferred diazo components are p-aminophenylthio and p-aminophenethylthio-hydroquinone- 0,0<SP>1</SP>-diacetates and 4-(4<SP>1</SP>methyl-2<SP>1</SP>,5<SP>1</SP>-bis-acetoxyphenylthio)-2-methoxyaniline. The preparation of the diazo components is in Group IV(b). Compounds of formula Y-S-R-Ar(Z<SP>1</SP>) n - N=N-X<SP>1</SP>-N=N-Ar(Z<SP>1</SP>) n -R-S-Y, Y-S-R-Ar(Z<SP>1</SP>) n -N=N-X<SP>1</SP>-N= N-Ar(Z<SP>2</SP>) n -S-Y and Y-S-Ar-(Z<SP>2</SP>) n -N= N-X<SP>1</SP>-N=N-Ar(Z<SP>2</SP>) n -S-Y may be obtained by coupling 2 mols of diazo compounds into 1 mol of coupling components such as 1,6- dehydroxynaphthalene, which allow of a second coupling. When the initial diazo components are coupled with components which contain a diazotisable amino group the resultant azo compound may be diazotised and further coupled to yield e.g. compounds of formulae Y-S-R-Ar(Z<SP>1</SP>) n -N =N-X<SP>1</SP>-N = N-X<SP>2</SP> and Y-S-Ar(Z<SP>2</SP>) n -N=N-X<SP>1</SP>-N=N-X<SP>3</SP>. Examples of monoazo compounds to be used as diazo components are 2,5 - dimethoxy - 4 - [p - (2<SP>1</SP>,5<SP>1</SP>-bis-acetoxyphenylthio- and -acetoxyphenylthioethyl)-phenylazo]-anilines. The products are used as dye developers in photographic compositions (see Group XX). Examples are provided of the preparation of the dyes and their use in photographic compositions and processes. Specifications 804,971, 804,972, 811,579, 853,478 and 853,479 are referred to.