Patent GB-609275-A (GB)
Title: Azo dyestuffs
IPC: C09B31/06
Filed: 1946-03-11
Abstract: Water-soluble secondary disazo dyestuffs are manufactured by coupling a diazotized aminoazo compound of the general formula R-O-X-N=N-Y-NH2 (wherein R represents a monohydroxyalkyl group or the sulphuric ester thereof, X an aryl nucleus of the benzene series which may carry substituents other than nitro, carboxylic acid or sulphonic acid groups and in which the azo group is in m- or p-position to the R-O-grouping, and Y a benzene or naphthalene nucleus in which the diazotizable amino group is in p-position to the azo group and which may carry further substituents other than nitro, carboxylic acid or sulphonic acid groups) with a phenol of the benzene series which is capable of coupling in the p-position to the hydroxy group and which is substituted in the 2-position with a hydrocarbon radical of at least four carbon atoms attached directly or through an oxygen atom, and which may carry further substituents other than nitro, carboxylic or sulphonic acid groups, and, where R is a monohydroxyalkyl group, further treating the product with a known agent suited to give the sulphuric ester thereof.  The products, in the form of their alkali metal or ammonium salts, dye cellulose acetate artificial silk in dischargeable orange shades from a neutral, slightly acid or slightly alkaline bath, e.g. from a neutral bath containing common salt, and are suitable for application from dilute or "long liquor" dyebaths such as are employed in dyeing with the winch.  They may also be employed for printing cellulose acetate artificial silk and for dyeing other artificial fibres (especially those from nylon), wool, natural silk, tin-weighted silk and leather.  Examples describe the production of the following dyestuffs: p-aminophenyl b -hydroxyethyl ether sulphuric ester --> a -naphthylamine or 2 : 5-dimethoxyaniline or 2-methoxy-5-methylaniline --> 2-hydroxydiphenyl; p-aminophenyl b -hydroxyethyl ether sulphuric ester --> sodium m-toluidinomethanesulphonate (hydrolysed) --> o-n-butylphenol; p-aminophenyl b -hydroxyethyl ether sulphuric ester --> 2 : 5-dimethoxyaniline --> o-benzylphenol or o-cyclohexylphenol; p-aminophenyl b -hydroxyamyl ether sulphuric ester --> 2 : 5 - dimethoxyaniline --> o - benzyl - phenol.  A table gives further examples in which the following additional components are used: first components: the sulphuric esters of m-aminophenyl b -hydroxyethyl ether, p-aminophenyl b -hydroxyamyl ether and 2-chloro- and 2-methyl-4-aminophenyl b -hydroxyethyl ether; middle components: o-toluidine, p-xylidine, o- and m-anisidine, and aniline; end components: o-n-butoxyphenol and o-hydroxydiphenyl ether.  In a further example, p-aminophenyl b -hydroxyethyl ether is diazotized and coupled with sodium m - toluidino - methansulphonate, the monoazo dyestuff is hydrolysed with aqueous sodium hydroxide, diazotized and coupled with o-benzylphenol, and the product is treated with 70-80 per cent sulphuric acid.  Other components specified are: first components: p-aminophenyl g -hydroxypropyl and d -hydroxybutyl ethers, g -(p-aminophenoxy)-n-butanol and 3-methyl-4-aminophenyl b -hydroxyethyl ether, or their sulphuric esters; middle components: 3 - amino - 4 - methoxyacetanilide and 2 : 5 - diethoxyaniline; end components: o-n-amyloxyphenol, o-n-hexyloxyphenol and o-benzyloxyphenol.  Specification 455,643 is referred to.