Patent GB-483278-A (GB)
Title: Improvements in or relating to the manufacture of dyestuffs and the colouration of textile and other materials therewith
IPC: C09B57/00
Filed: 1936-10-12
Abstract: Nitro dyes; cellulose esters or ethers, dyeing.-Dyestuffs, suitable more especially for colouring textile and other materials made of or containing organic esters or ethers of cellulose, are obtained by treating with a sulphating agent an aromatic compound (other than an azo or an anthraquinone compound) containing a hydroxyalkyl group linked to an aryl nucleus directly or through oxygen, sulphur or an -NR- group, wherein R is H or alkyl, and containing at least one nuclear amino group and at least one nuclear nitro group.  An -NR- group substituted by a hydroxyalkyl group may be the sole amino group present. Alternatively the dyestuffs may be obtained by the action of a sulphatoalkylating agent upon an appropriate aromatic compound. Certain of the dyestuffs containing more than one aryl group may also be obtained by reaction of an aromatic compound containing a halogen atom with an aromatic compound containing an amino group having reactive hydrogen, at least one of the reactants containing a nuclear nitro group and at least one containing a sulphoatoalkyl group linked to an aryl nucleus as above.  Specified dyestuffs having a single aryl nucleus are the sulphato esters of 4-chloro-2-nitro-1-(b -hydroxyethyl) aniline, 2 : 4-dinitro-1-(b -hydroxyethyl)aniline and corresponding derivatives of toluene and naphthalene.  Specified dyestuffs having a plurality of aryl nuclei linked directly or through O, S, NH, CH2, CO or CO.NH are the sulphato esters of (a) 3 - nitro - 4 - (b  - hydroxyethyl)aminodiphenyl, (b) 1 - benzoylamino - 3 - (b  - hydroxyethyl) amino - 4 - nitrobenzene, (c) 2 : 4 - dinitro-41 - (b  - hydroxyethyl)aminodiphenylamine, (d) its 41 - N - ethyl derivative and (e) 4-(21 : 41 - dinitrobenzoyl)amino - N - ethyl-b -hydroxyethyl aniline.  The sulphato ester of (d) is obtainable by condensing 2 : 4-dinitrochlorobenzene with 1-amino-4-N-(ethyl-b -sulphato ethyl) amino benzene, that of (e) by condensing 2 : 4-dinitrobenzoyl chloride with the same. Additional auxochromic groups, e.g. phenolic groups or other substituents, e.g. halogen or alkyl or alkoxy groups may also be present and amino groups may be acidylated.  In examples of the manufacture of the dyestuffs, (1) 2 : 4-dinitro-41-(ethyl-sulphatoethyl) aminodiphenylamine is obtained by treating 2 : 4 - dinitro - 41 - (ethyl - b  - hydroxyethyl) aminodiphenylamine with conc. sulphuric acid, (2) 2 : 4 - dinitro - 41 - (sulphatoethoxy) diphenylamine is similarly obtained from 2 : 4 - dinitro - 41 - (b  - hydroxyethoxy)diphenylamine, (3) the product of (1) is obtained by treating 4 - amino - N - (ethyl - b  - hydroxyethyl) aniline with conc. sulphuric acid and condensing the resulting sulphato ester with 2 : 4 - dinitrochlorobenzene.  In an example of the dyeing process, cellulose acetate yarn or fabric is worked for 1/4 hour in an aqueous bath at 45 DEG  C. containing 2 : 4-dinitro-41-(sulphato-ethoxy)diphenylamine and the temperature is raised, with additions of Glauber salt, to 80 DEG  C. and so maintained for 1 hour, to obtain a full golden yellow dyeing.  2 : 4 - Dinitro - 41 - (ethyl - b  - hydroxyethyl) diphenylamine is precipitated out on condensing at 60 DEG  C. 2 : 4-dinitrochlorobenzene with the mixture obtained by reducing in aqueous solution the azo dyestuff, sulphanilic acid --> ethyl-b -hydroxyethylaniline.  2 : 4 - Dinitro - 41 - (b  - hydroxyethoxy)diphenylamine is obtained by condensing 2 : 4-dinitrochlorobenzene with 4-b -hydroxyethoxyaniline.  1 - Amino - 4 - N - (ethyl - b  - sulphatoethyl) amino benzene is obtainable by treating with conc. sulphuric acid the reduction product from the azo dyestuff, sulphanilic acid --> ethyl-b -hydroxyethyl aniline.