Patent GB-616977-A (GB)
Title: Manufacture of a new azo-dyestuff
IPC: C09B33/28
Filed: 1945-12-18
Abstract: An azo dyestuff is manufactured by coupling two molecular proportions of diazotized 4-amino - 41 - hydroxy - 1 : 11 - azobenzene - 3 : 31 - dicarboxylic acid in an alkaline medium with one molecular proportion of 5 : 51-dihydroxy-2 : 21-dinaphthylamine - 7 : 71-disulphonic acid. The product may be treated in the dyebath or on the fibre (especially fibres containing cellulose, such as cotton or artificial silk or staple fibres of regenerated cellulose) with agents yielding metals, e.g. compounds of chromium, cobalt, nickel, iron, manganese or especially copper (e.g. by treatment in the dye bath with a solution of copper sulphate and tartaric acid neutralized with alkali, or by after-treatment with copper sulphate in an acid medium). Specification 452,326 is referred to.  4 - Amino - 41 - hydroxy - 1 : 11 - azobenzene - 3 : 31-dicarboxylic acid is obtainable by diazotizing 1 - amino - 4 - nitrobenzene - 3 - carboxylic acid, coupling with salicylic acid and reducing the nitro group by means of sodium sulphide.  The Specification as open to inspection under Sect. 91 comprises also the manufacture of other dyestuffs by diazotizing a monoazo dyestuff of the general formula <FORM:0616977/IV (c)/1> wherein R represents a benzene or naphthalene residue containing a hydroxy group and, in o-position thereto, a carboxyl group (including additionally 4-amino-41-hydroxy-51- or -61-methyl- or -51-methoxy-1 : 11-azobenzene-3 : 31-dicarboxylic acid, 4-aminobenzene - 1 : 11-azo-naphthalene - 41 - hydroxy - 3 : 31 - dicarboxylic acid, and other substitution products of these compounds, e.g. those obtainable by sulphonation or nitration) and coupling with a 5-naphthol-7-sulphonic acid containing in the 2-position a nitrogen-containing substituent in which the nitrogen is bound directly to the 2-carbon atom, e.g. an azo group or a free or preferably substituted amino group, and optionally containing further substituents, such as a further sulphonic acid group or an azo group, e.g. in the 1-position (including additionally 2-amino-5-naphthol-7-sulphonic acid and -1 : 7-disulphonic acid, N-acyl-, N-aryl- and other N-substitution products of these acids, e.g. 2-(p-sulpho- or p - carboxy - phenyl) - amino - 5 - naphthol - 7 - sulphonic acid, di-(5-hydroxy-7-sulpho-2-naphthyl)-ethylenediamine and -urea, 2-(31- or 41-amino) - benzoylamino-5-naphthol-7-sulphonic acid, and the binary and ternary condensation products from 1 mol. of the aforesaid acids in which the amino group is primary, 1 mol. of cyanuric chloride and 1 mol. or 2 mols. of the same or different primary or secondary amines such as mono- or di-methylamine, aniline, p-toluidine, N - methylaniline, anilinesulphonic acids, 1-amino-4-hydroxybenzene-3-carboxylic acid, a -naphthylamine, aminonaphthols and their sulphonic acids or 4-amino-41-hydroxy-1 : 11-azobenzene-31-carboxylic acid, also azo compounds obtained by coupling any diazo compound in acid medium with a 2-amino-5-naphthol-7-sulphonic acid capable of coupling in the 1-position, or by coupling a diazotized 2-amino-5-naphthol-7-sulphonic acid with any coupling component, with or without intermediate substitution of the 5-hydroxy group).  If desired, the products are diazotized and coupled with a further coupling component (especially those containing lake-forming groups, e.g. 1-hydroxy-2- or -3-methylbenzene-6-carboxylic acid, the asymmetrical urea from 2-amino-5-naphthol-7-sulphonic acid and 1-amino-4 - hydroxybenzene - 3 - carboxylic acid, or 8-hydroxyquinoline), or are coupled with a diazo compound, or are treated with an acylating agent (e.g. acetic anhydride, acetyl chloride, chloracetyl chloride, benzoyl chloride, 4-chloro-or -methoxy-benzoyl chloride or phosgene) or with a heterocyclic compound containing two or three reactive halogen atoms (e.g. cyanuric chloride, 1-phenyl-3 : 5-dichlorotriazine, 2 : 4 : 6-tribromopyrimidine or 2 : 4-dichloroquinazoline, any remaining halogen atoms of which may be previously or subsequently reacted with other primary or secondary amines such as aniline, N-methylaniline, sulphanilic acid, 1-amino-4-hydroxybenzene-3-carboxylic acid or 4-amino-41 - hydroxy - 1 : 11 - azobenzene - 31 - carboxylic acid), or these treatments may be used in combination.  When the 5-naphthol-7-sulphonic acid derivative employed is capable of coupling twice, 1 mol. thereof may be coupled in either order with 1 mol. of the diazo compound of an aminoazo dyestuff of the general formula above and 1 mol. of the diazo compound of any other amine, preferably one containing a hydroxy or carboxyl group in o-position to the amino group (e.g. o-aminophenol, 4-chloro- or 4- or 5-nitro-2-aminophenol, sulphonic acids or sulphonamides of these compounds, anthranilic acid or 1-amino-4-acetylaminobenzene-2-carboxylic acid).  Some of the components specified are employed in additional examples of the production of disazo, trisazo and tetrakisazo dyestuffs.  This subject-matter does not appear in the Specification as accepted.