Patent GB-723632-A (GB)
Title: Disazo dyestuffs capable of chroming and process for their manufacture
IPC: C09B31/02
Filed: 1952-09-01
Abstract: The invention comprises disazo dyestuffs capable of chroming of formula <FORM:0723632/IV (c)/1> where R is a radicle of a diazo component of the benzene or naphthalene series which may be substituted, R1 is a radicle of any desired coupling component of the naphthalene series or one containing a keto-methylene group which has a hydroxy group in the ortho position to the azo bridge and may contain further substituents and the radicles R and R1 contain together at least one water-solubilizing group.  They may be made by coupling one mol. of a diazo compound of an amine <FORM:0723632/IV (c)/2> with one mol of the appropriate coupling component or by coupling one mol. of a diazo compound of the benzene or naphthalene series with one mol. of the dyestuff <FORM:0723632/IV (c)/3> The ortho hydroxy amine may be made by coupling a diazotized amine of the benzene or naphthalene series with a 1-hydroxy-2-N-acylaminobenzene with subsequent hydrolysis of the acylamino group.  Specified hydroxy-N-acylaminobenzenes are 1-hydroxy-2-N-acetyl-, formyl-, propionyl-, oxalyl-, benzoyl-, carbomethoxy- and carboethoxy-aminobenzene.  The ortho-hydroxy amine may also be made by reduction of the corresponding nitro derivative prepared by nitrating the 4-hydroxyazobenzene obtained by coupling diazotized amines of the benzene or naphthalene series with 1-hydroxy-2-nitrobenzene.  Specified amines for coupling with the 1-hydroxy-2-N-acylamino or 2-nitro benzene or hydroxybenzene are aniline, 1-amino-2-, 3- or 4-methyl, -ethyl, -methoxy, -chloro, -nitro, -sulpho or -carboxy, benzene, 1-amino-2,4-, 2,5- or 2,6-dimethyl or diethylbenzene, 1-amino-2,4,6-trimethyl or triethylbenzene, 1-amino-2-methyl benzene-4- or 5-sulphonic acid, 1-amino-2,4-dimethyl benzene 5- or 6-sulphonic acid, 1-amino-2,5-dichlorobenzene-4-sulphonic acid, 1-amino-4-hydroxybenzene-3-carboxylic acid, 1-amino-3-hydroxy-4 - carboxy - benzene - 5 - sulphonic acid, 1 - amino - 2 - methyl - 6 - chlorobenzene - 4 - or 5-sulphonic acid, 1- or 2-aminonaphthalene, 1-aminonaphthalene-2, 4-, 5-, 6-, 7- or 8-sulphonic acid, 2-aminonaphthalene-1-, 5-, 6-, 7- or 8-sulphonic acid.  Azo components specified for coupling in the ortho position to the hydroxy group are 2-hydroxynaphthalene, 2-N-benzoylamino - 5 - hydroxy - naphthalene - 7 - sulphonic acid, 2 - hydroxy - 6 - tert. - amylnaphthalene, 1-N-acetyl-, carbethoxy or carbo-(2 - ethoxy) - ethoxy - amino - 7 - hydroxynaphthalene, 2-hydroxy-3- or 6-carboxy, 3-carboxylic acid-N-phenylamido-, 4, 6-, 7- or 8-sulpho - naphthalene, 1 - hydroxy - 5,8 - dichloro-, 4-benzoyl- and 4- or 5-sulpho-naphthalene, 2 - N - phenyl - amino - 8 - hydroxynaphthalene - 6 - sulphonic acid, 3 - methyl-5 - pyrazolone, 1 - phenyl - 3 - methyl or carboxy - 5 - pyrazolone, 1 - phenyl - 5 -pyrazolone-3-carboxylic acid amide-1-(31-sulphoamidophenyl) - 3 - methyl - 5 - pyrazolone or barbituric acid, the aryl nucleus of the pyrazolones optionally containing substituents such as chlorine atoms, nitro, alkyl, carboxy and sulpho groups.  The monazo dyestuffs used in the second alternative for the preparation of the compounds of the invention may be made by coupling diazotized o-hydroxy aniline with the appropriate azo component and the above-specified azo components and diazo compounds of the amines specified in connection with the first alternative may be used. The dyestuffs dye wool in the after-chroming process in yellowish-brown, red, reddish brown, brown, greyish brown, olive-green or green tints.  Some dyes may be used in the metachrome process.