Patent GB-471396-A (GB)
Title: Manufacture of azo-dyestuffs
IPC: C09B29/00
Filed: 1936-09-07
Abstract: Azo dyestuffs are manufactured by coupling a diazo compound of an aromatic amine with a coupling component, the group directing coupling being a non-substituted or substituted amino group (including a group in which the nitrogen forms part of a hydrogenated heterocyclic ring which may be condensed to an aromatic nucleus), the components used being such that the dyestuff molecule contains at least twice the group SO2R where R is alkyl, aralkyl or aryl. Advantageously, there are employed as diazo compounds those derived from aromatic amines of the formula <FORM:0471396/IV/1> where each of two Y's is SO2R and the remainder are hydrogen or any substituent, e.g. 1-aminobenzene - 2 : 4 - dialkyldisulphones such as 1 - aminobenzene - 2 : 4 - dimethyl-, -diethyl- and dipropyldisulphones; the corresponding aralkyl and aryl disulphones such as 1-aminobenzene-2 : 4-dibenzyl- or -di-(p-chlorobenzyl)-disulphones, 1 - aminobenzene - 2 : 4 - diphenyldisulphones or alkyl or alkoxy derivatives thereof; 1 - aminobenzene - 2 : 5 - dialkyldisulphones such as 1-aminobenzene-2 : 5-dimethyl-or -diethyldisulphone; the corresponding aralkyl- and arylsulphones such as 1-aminobenzene-2 : 5-dibenzyl- or -diphenyldisulphone; sulphones in which the aryl, aralkyl or alkyl residues are different, such as 1-aminobenzene-2 : 5-benzylmethyl- or -phenylethyldisulphone or -2 : 4-ethylmethyl-, -ethylbenzyl-, -phenylethyl- or -phenylbenzyldisulphone; or the alkyl, alkoxy, nitro or sulphonic acid derivatives of these bases. When the dyestuffs contain at least one sulphonic group in the molecule they are suitable for dyeing animal fibres, e.g. wool in an acid bath, or for printing acetate artificial silk; coupling components specified in this connection are: amino or aminohydroxy compounds of the benzene and naphthalene series, e.g. a - and b -naphthylamines and their sulphonic acids, the N-alkyl derivatives thereof, such as ethyl-b -naphthylamine and its sulphonic acids, aminohydroxynaphthalenes such as 1 : 5-aminonaphthol-2- or 7-sulphonic acid, 2 : 8-aminonaphthol, the 6-sulphonic acid thereof and its N-alkyl and aryl, e.g. phenyl, derivatives, diphenylamine and its sulphonic acids and alkylanilines such as ethylbenzylaniline and ethyl - (p - sulphobenzyl) - aniline.  When the diazo component contains only one sulphone group there must be used coupling components containing at least one sulphone group, e.g. aromatic amines containing a sulphone group in m-position to an amino, alkylamino, aralkylamino or arylamino group, such as 1-aminobenzene - 3 - methylsulphone, 1 - dimethylaminobenzene - 3 - methylsulphone or 1-di-(hydroxyethyl) - aminobenzene - 3 - methyl or ethylsulphone; or similar products of the naphthalene series such as 2-aminonaphthalene-6-methylsulphone or its N-alkyl or aryl derivatives.  Dyestuffs suitable for dyeing acetate artificial silk are obtained by using a diazo component free from sulphonic acid groups and as coupling component a simple aromatic base, e.g. aniline, o- or m-toluidine, p-xylidine, p-cresidine, 2 : 5-dihydroxyalkylaminobenzenes, naphthylamines, hydroxynaphthylamines such as 1 : 5- or 2 : 8-aminonaphthol, or amines which are alkylated or hydroxyalkylated in the amino group, or derivatives of the latter in which the hydroxy group is etherified or esterified.  The dyes for acetate artificial silk are preferably first brought into a fine state of subdivision, e.g. by grinding with dispersing agents such as sulphite cellulose lye or the sulphonated residues of benzaldehyde manufacture.  The p  pastes so obtained may be dried.  Examples describe the production of the following dyes: (1) 1 - aminobenzene - 2 : 4 - dimethylsulphone --> 2 : 8 : 6-acid; the product dyes wool red-violet shades; the diazo component may be replaced by 1 - aminobenzene - 2 : 4 - diethyl- or 2 : 5-dimethyl- or diethyldisulphones, or by dibenzyldisulphones; (2) 1 - aminobenzene - 2 : 4-dimethylsulphone --> 1 : 5 : 7-acid; the product dyes wool blue shades; the diazo component may be replaced by 1-aminobenzene-2 : 4-diethyldisulphone, by the corresponding dibenzyldisulphones, by 1-aminobenzene-2 : 5-benzylmethyldisulphone, or by 1-aminobenzene-2 : 4-ethylmethyl- or -phenylbenzyldisulphones, and the coupling component by 1 : 5 : 8- or 1 : 5 : 2 - acids; (3) 1 - aminobenzene - 2 : 4-dimethyldisulphone --> 1-amino-5-hydroxynaphthalene; the product when brought into suitable dispersion dyes cellulose esters and ethers violet blue shades and may also be used for colouring lacquers, varnishes and artificial masses; the coupling component may be replaced by m-toluidine, 1-amino-5-methyl-2-methoxybenzene, 1-amino-2 : 5-dimethoxybenzene, or N-hydroxyalkylaminobenzenes in which the hydroxy group may be alkylated or acylated, e.g. the products described in Specification 422,843; (4) 1-aminobenzene-2 : 4-dimethylsulphone --> ethyl-o -methoxyethylaniline; the product dyes cellulose esters and ethers orange shades, and may also be used for colouring lacquers; the coupling component may be replaced by ethyl-o -hydroxyethylaniline, 5-methoxy - 2 - methyl - 1 - (dimethoxyethyl)-aminobenzene or a 1-aminobenzene-3-methylsulphone alkylated or hydroxyalkylated at the nitrogen; in the last case the diazo component may be replaced by 1-amino-4-nitrobenzene-2-methylsulphone; (5) 1 - aminobenzene - 2 : 4-diethylsulphone --> 1 : 5 : 2-acid; the product dyes wool blue shades; (6) 1-aminobenzene-2 : 4-benzylethyldisulphone --> 1 : 5 : 2-acid; the product dyes wool blue shades; (7) 1-aminobenzene-2 : 4-dipropyldisulphone --> 1 : 5 : 2-acid; the product dyes wool blue shades; (8) 1 - aminobenzene - 2 : 4 - dibutyldisulphone --> 1 : 5 : 2-acid; the product dyes wool blue shades; (9) 1-aminobenzene-2 : 4-diethyldisulphone --> the product obtained by treating 1 : 5-aminonaphthol with epichlorhydrin in boiling butyl alcohol; the product dyes acetate artificial silk blue shades capable of white discharge; the diazo component may be replaced by 1-aminobenzene - 2 : 4-dimethyldisulphone, and the coupling component by other alkylated derivatives of 1 : 5-aminonaphthol, e.g. those from ethylene chlorhydrin, ethyl chloracetate or chloracetamide.  In further examples: (10) wool is dyed bluish Bordeaux with the product of (5) from a bath containing sodium sulphate and sulphuric acid; (11) acetate artificial silk yarn is dyed blue with the product of (9) which has been pasted with, for example, turkey red oil, sulphite cellulose lye or the sulphonation products from the residues of benzaldehyde manufacture and dissolved in soap solution. Specification 451,970 also is referred to.  Amines containing two alkyl- or aralkylsulphone groups are obtainable by converting a halogen-benzenedisulphonic acid into its halide, reducing this to the disulphinic acid, treating this with an alkylating agent, e.g. methyl or ethyl bromide, or an aralkylating agent, e.g. benzyl chloride, and treating the product with ammonia.  Amines containing two arylsulphone groups are obtainable by condensing chlorobenzenedisulphonic acid halides with aromatic hydrocarbons, e.g. benzene or toluene, in the presence of aluminium chloride, and treating the product with ammonia. 1-Dimethylaminobenzene-3-methylsulphone is obtainable by converting nitrobenzene-3-sulphochloride into the corresponding sulphinic acid, reacting the sodium salt thereof with methyl bromide, reducing and methylating, e.g. with methyl bromide. 1-Di-(hydroxyethyl)-aminobenzene-3-methyl-and ethylsulphones are obtainable by treating aminobenzene - 3 - methyl- or ethylsulphone with ethylenechlorhydrin.  2-Aminonaphthalene-6-methylsulphone and its N-alkyl or aryl derivatives are obtainable by converting 2-nitronaphthalene-6-sulphochloride into the corresponding sulphinic acid, treating the sodium salt thereof with methyl bromide, reducing, and, if desired, treating with alkylating or arylating agents.  The Specification as open to inspection under Sect. 91 specifies as additional diazo components 2 - aminonaphthalene - 4 : 8 - diethyldisulphone and 1 - aminonaphthalene - 2 : 4 - diethyl- and dimethyldisulphones.  This subject-matter does not appear in the Specification as accepted.  Reference has been directed by the Comptroller to Specifications 451,970, 456,343, 457,679, and 457,687.