Patent GB-793587-A (GB)
Title: Quaternary ammonium monoazo dye salts and their use
IPC: C09B44/12
Filed: 1956-01-27
Abstract: The invention comprises dyestuffs of formula [A1-N=N-B]+X-the cation residue of which is free from sulphonic acid or carboxyl groups, A1 is a mono or poly-nuclear N-alkyl pyridinium ring system which is bound to the azo group by a C atom that forms part of the heterocyclic ring, B is the residue of an azo component and X- is an anion.  They are made by alkylating the corresponding dyestuff preferably in an inert organic solvent medium.  The pyridine ring may be fused with a benzene ring to form a quinoline ring and the ring systems may contain substituents such as alkyl, alkoxy, aralkyl, aryl, nitro, acylamino, carboxylic acid ester and halogen groups. The starting dyestuffs may be made by appropriate coupling reactions or by other methods, e.g. 2-arylazo pyridine and quinoline compounds may be made by condensing the corresponding 2-amino-pyridines or -quinolines with nitroso aryl compounds the use of p-nitroso dialkyl and benzyl alkyl anilines and p-nitroso diphenylamines being especially preferred.  When the dyestuffs are made by coupling reactions, e.g. from 3-amino-pyridine, B may be derived from an acylacetic acid arylamide, an o- or p-hydroxy- or -amino-aryl radicle, a 3-indolyl radicle or a 5-amino- or -hydroxy-pyrazole.  The amino group in the preferred p-aminoaryl azo dyestuffs may be primary, secondary or tertiary and the amino group may be substituted by aliphatic, araliphatic, alicyclic, aromatic or heterocyclic groups.  Further substituents such as hydroxy-, fluor-, cyan- and phenyl-alkyl, alkoxy and alkyl-, alkoxy- and halogen-phenyl and -benzyl residues may also be present.  Aliphatic substituents of the amino group may be formed into rings such as in the piperidino, morpholino, 1,2,3,4-tetrahydroquinoline, lilolidine, julolidine and perimidine compounds.  The preferred p-aminophenyl radicle may contain halogen, alkyl, alkoxy, nitro, acylamino and alkylsulphonyl substituents.  Indicated as alkylating agents are esters of strong mineral and organic sulphonic acids with preferably low alcohols.  X- may, however, be derived from carboxylic acids such as acetic, formic, oxalic, lactic and tartaric and may also, when the base is stable be OH.  Under energetic alkylating conditions any non-tertiary amino groups present may be alkylated.  The products may be used in the form of their zinc chloride double salts and X- may also be anions such as chloro-zincate or cadmiate.  The dyestuffs dye cellulose fibres mordanted with tartar emetic and tannin, silk, leather and polyacrylonitrile fibres.  In examples which illustrate the preparation of the dyestuff salts and their use in dyeing the above-indicated materials in violet, yellow and red shades components corresponding to A1 are 2-, 3- and 4-aminopyridine, 4-and 6-methyl-2-aminopyridine, and 2-aminoquinoline and its 4- and 8-methyl derivatives, components from which B is derived being 1-N,N-dimethyl- and -diethyl- and N-ethyl-N - benzyl - amino - 4 - nitroso - benzenes, phenol, a - and b -naphthols, N,N-dimethyl- and -diethyl - anilines, N - ethyl - N - benzyl - and 3 - methyl - anilines and 3 - hydroxy - 5,6-naphtho - 1,2,3,4 - tetrahydropyridine, and the alkylating agents are dimethyl and diethyl sulphate and p-toluenesulphonic acid methyl and ethyl esters.