Patent GB-817374-A (GB)
Title: Benzothiazole-monoazo-isonicotinic acid compounds and materials colored therewith
IPC: C09B29/033
Filed: 1955-11-03
Abstract: Acrylonitrile polymers, and cellulose alkyl carboxylic esters with 2 to 4 carbon atoms in the acid radical, are dyed with a compound of formula <FORM:0817374/IV (a)/1> where Ar is an o-arylene radical of the benzene series, R is H or an alkyl group of 1-4 carbon atoms, an alkoxyalkyl group of 3-6 carbon atoms or a cyclohexyl group and X is H or an alkyl group of 1-4 carbon atoms, or with chromium, cobalt, copper, iron, manganese, nickel or vanadium complexes thereof. Dyeing may be effected in conventional fashion in substance or on the fibre, or the dyestuffs or their metallizing agents may be incorporated in the spinning dopes.  A particular class of dyestuff concerned is that where X is H and R is alkyl of 1-4 carbon atoms. The arylene residue may be unsubstituted or contain substituents such as alkylsulphonyl, N-alkylsulphonamide, alkoxy, alkyl, hydroxyalkyl, acylamino, cyano, thiocyano, thiomethyl, trifluoromethyl or nitro groups or a chlorine atom.  For the preparation of the dyestuffs and for lists of a number of components to be used therein see Group IV (c).  Hydrolysed and unhydrolysed cellulose acetate, propionate, butyrate, acetate-propionate and acetate-butyrate are mentioned.  The metalfree and metallized dyes colour fibres of graft polymers of acrylonitrile made by graft polymerizing acrylonitrile alone or together with one or more other monoethylenic monomers with a preformed polymer which may be a homo-, inter- or ter-polymer. The dyes are particularly useful with graft polymers containing at least 5 per cent by weight of combined acrylonitrile grafted to the preformed polymer molecule and especially for fibres made by graft polymerizing acrylonitrile and an acrylamide or methacrylamide with a preformed copolymer of acrylonitrile and the same or different acrylamide or methacrylamide.  Preformed polymers are preferably homopolymers of a vinyl pyridine, an acrylamide, a maleamide, a fumaramide, an acrylate, a methacrylamide, a methacrylate, an itaconamide, a citraconamide, a fumaramate, an itaconamate, a citraconamate, a maleamate, or a vinyl ester or an interpolymer of two or more of such monomers with each other or of at least one of such monomers with monomers such as styrene, acrylonitrile, substituted styrenes, vinyl or vinylidene chlorides, vinyl ethers, dialkyl maleates, alkenyl ketones, dialkyl fumarates, acrylic and methacrylic acids, substituted acrylonitriles, fumaronitrile and ethylene.  Examples are given illustrating the dyeing of certain of the above indicated polyacrylonitriles with the metal-free and metallized dyestuffs and the preparation of films and filaments from cellulose acetate dopes containing certain of the metal dyestuffs. Red and blue shades are obtained.  Specifications 764,296, 764,297, 764,298, 781,435 and 816,396 are referred to.ALSO:Citrazinates of formula <FORM:0817374/IV (b)/1> where R is an alkyl group of 1-4 carbon atoms, an alkoxyalkyl group of 3-6 carbon atoms or a cyclohexyl group and X is H or an alkyl group of 1-4 carbon atoms are prepared by normal esterification processes and used as dyestuff intermediates (see Group IV (c)).  Detailed preparations of cyclohexyl, isopropyl, sec. and isobutyl and b -methoxy-, -ethoxy- and -butoxy-ethyl citrazinates and 2-isobutoxy-6-hydroxy-isonicotinic acid isobutyl ester are given.  Specifications 764,296, 764,297, 764,298, 781,435 [all in Group IV(a)], and 816,396 are referred to.ALSO:The invention comprises compounds of formula <FORM:0817374/IV (c)/1> where Ar is a substituted or unsubstituted ortho-arylene radicle of the benzene series, R is H, an alkyl group of 1-4 C atoms, an alkoxyalkyl group of 3-6 C atoms or a cyclohexyl group and X is H or an alkyl group of 1-4 C atoms, and their chromium, cobalt, copper, iron, manganese, nickel or vanadium complexes obtainable by reacting the compounds with salts of the metals.  The metal-free dyestuffs are made by coupling appropriate diazotized 2-aminothiazoles and isonicotinic acid compounds.  Specified aminothiazoles are 2-amino-6-methyl-, -ethyl-, -n-propyl-, n-butyl-and - trifluoromethyl - sulphonyl -, - methoxy -, -ethoxy-, -n-propoxy-, -n-butoxy-, -methyl-, - ethyl -, - n and - iso - propyl -, - n - and -iso-butyl-, -b -hydroxyethyl-, -g -hydroxypropyl-, -g -hydroxybutyl-, -acetyl-, -n-propionyl-and -n-butyryl-amino-, -thiomethyl-, -thiocyano-, -cyano-, -trifluoromethyl-, -chloro- and -nitro-, -4,7-dimethoxy- and -diethoxy-, -5,6-dimethoxy- and -4,6-dimethylbenzothiazoles, 2 - acetylamino - 6 - thiocyano - benzothiazole, and 2 - aminobenzothiazole - 6 - N - methyl-, -ethyl-, -n-propyl- and -n-butyl-sulphonamides.  Specified isonicotinic acid compounds are citrazinic acid, methyl, ethyl, n- and iso-propyl, n-, iso- and sec.-butyl, cyclohexyl, b -methoxy-, -ethoxy- and n-propoxy- and -butoxy-ethyl citrazinates, methyl-, isopropyl-, sec.-butyl and cyclohexyl - 2 - hydroxy - 6 - methoxyisonicotinates, ethyl-, isobutyl- and cyclohexyl-2-hydroxy - 6 - ethoxyisonicotinates, ethyl - 2 - hydroxy - 6 - n - propoxy - isonicotinate, ethyl-, n-butyl- and cyclohexyl-2-hydroxy-6-n - butoxyisonicotinate and 2 - hydroxy - 6 - methoxy-, -ethoxy-, n-propoxy- and n-butoxy-isonicotinic acids. Specified salts for metallizing are halides, sulphates, formates, acetates, lactates, cyanides and thiocyanates.  Metallization is preferably effected by heating the reaction mixture with steam in the presence of organic solvents such as cellulose acetate and acetate propionate, acrylonitrile polymers, polyamides, formamide and the monomethyl ether of ethylene glycol.  Metallization may be effected in substance or on the fibre.  The dyestuffs dye cellulose acetate, especially textile materials, comprising a hydrolysed or unhydrolysed cellulose alkyl carboxylic acid ester of 2-4 C atoms, the preferred method of dyeing being to metallize on the fibre with a thiocyanate, especially nickel thiocyanate, and fibres of polyacrylonitrile and graft polymers obtained from acrylonitrile alone or together with one or more other ethylenic monomers with a preformed polymer (see Specifications 764,296, 764,297, 764,298 and 781,435).  Specified preformed polymers are vinyl pyridines, acrylamides, maleamides, fumaramides, acrylates, methacrylamides, methacrylates, itaconamides, citraconamides, fumaramates, itaconamates, citraconamates, maleamates and vinyl esters and interpolymers of the above with each other or with monomers containing a -CH = C < group such as styrene, acrylonitrile, substituted styrenes, vinyl or vinylidene chlorides, vinyl ethers, dialkyl maleates, alkenyl ketones, dialkyl fumarates, acrylic acid, methacrylic acid, substituted acrylonitriles, fumaronitrile and ethylene.  Dyeing of the above cellulosic and acrylonitrile fibres and nitrogenous materials such as wool, silk and nylon may be effected in conventional fashion.  Examples and a Table are provided illustrating the preparation of the metal-free and metallized dyestuffs and their use in dyeing and colouring textiles, films and mouldings made from cellulose acetate, nylon and acrylonitrile graft polymers in shades of red, violet, orange and brown, the reactants used being chosen from those specified above reactants and the following additional benzothiazoles: 2-aminobenzothiazole and its 4- and 5-methoxy- and 6-bromo-, isopropylsulphonyl- and isobutyl-sulphonyl-derivatives. Specifications 764,296, 764,297, 764,298, 781,435, [all in Group IV (a)], and 816,396 are referred to.