Patent GB-599278-A (GB)
Title: Improvements in dyes and in coloured fibres, foils and films
IPC: D01F1/10
Filed: 1945-07-20
Abstract: Fibres, foils and films of fibre- or film-forming materials soluble in organic liquids (e.g. celluloses esters and ethers and polymerized vinyl compounds) are coloured in yellow shades by means of monohydroxyazobenzenes free from sulphonic, carboxylic and nitro groups and having, as a substituent in the benzene nucleus carrying the hydroxy group, an aliphatic hydrocarbon radical containing at least 12 carbon atoms, which dyestuffs are made by coupling a diazotized aminobenzene free from hydroxy groups with a monohydroxybenzene having as a nuclear substituent an aliphatic hydrocarbon radical containing at least 12 carbon atoms, both components being free from sulphonic, carboxylic and nitro groups. The aliphatic hydrocarbon radicals may be saturated or unsaturated, straight- or branched-chain, primary, secondary or tertiary, and should preferably contain a chain of at least 6 or 8 carbon atoms counting from and including the one at which the radical is attached to the nucleus.  Suitable coupling components are the products obtained by heating a hydroxybenzene (e.g. phenol, a cresol, e.g. m-cresol, or a hydroxy diphenyl, e.g. p-hydroxydiphenyl) with an aliphatic alcohol containing at least 12 carbon atoms (e.g. dodecyl, hexadecyl, octadecyl or oleyl alcohol) in the presence of zinc chloride, whereby the aliphatic radical enters the p-position to the hydroxy group if free, otherwise the o-position.  The coloration may be effected by adding the dye, e.g. in a proportion of 0.5-2.5 per cent on the weight of fibre- or film-forming material, to a solution of the latter in an organic solvent, from which fibres may be spun by dry or wet methods and may then be assembled into yarns or may be cut into staple fibre which, alone or mixed with other textile fibres (e.g. of wool, silk, cotton or regenerated cellulose) may be converted into yarn, and the yarn consisting of or containing the coloured fibres may be woven or knitted into fabrics.  The coloured materials may be topped with other dyes, particularly direct dyes for cellulose esters or ethers, e.g. water-insoluble dyestuffs of the nitrodiarylamine, azo or aminoanthraquinone series, which topping colours may be applied, uniformly or locally, in aqueous solution or dispersion or in solution in organic solvents.  The monohydroxyazo dyestuffs of the invention may also be applied in any of the ways described in Specification 550,659.  In examples: (1) phenol is heated with oleyl alcohol and zinc chloride, the resulting oleylphenol is coupled with diazotized aminoazobenzene, and the dyestuff obtained is added to a solution of cellulose acetate in acetone from which filaments are dry-spun; (2) the aminoazobenzene in (1) is replaced by p-benzoylaminoaniline; (3) the oleyl alcohol in (1) is replaced by sec.-dodecyl alcohol, whilst the aminoazobenzene may be replaced by p-aminoacetanilide or p-aminobenzanilide. Additional diazo components specified are aniline, chloranilines, toluidines, zylidines, anisidines and aminoazotoluene, and reference is also made to the coloration of cellulose propionate, butyrate, acetopropionate, acetobutyrate and nitroacetate and methyl, ethyl and benzyl cellulose.  Specifications 489,562 and 551,435 also are referred to.  The Provisional Specification comprises the manufacture and use of azo dyes, preferably from sulphonic, carboxylic and nitro groups, obtained by coupling diazo compounds having, as nuclear substituents, aliphatic radicals containing at least 8 carbon p atoms united by carbon to carbon linkages, and refers additionally to Specifications 282,036, 313,451, [both in Class 15 (ii)], and 460,575.