Patent GB-403621-A (GB)
Title: Colouration of textile materials
IPC: D06P3/44
Filed: 1932-05-12
Abstract: Azo dyes, forming on the material; vat dyes, dyeing with; cellulose ester or ethers, dyeing; regenerated celluloses, dyeing; printing.--Mixed shades are produced on textile materials, and especially on materials made of or containing cellulose esters or ethers, by applying thereto or incorporating therein a diazotizable amine, a coupling component and a free leuco compound of a vat dyestuff or a salt of such leuco compound and thereafter effecting diazotization and coupling and development of the vat dyestuff by oxidation.  The amine, coupling component and leuco vat dyestuff may be applied from a single bath, padding liquid or the like or they may be applied separately.  The oxidation of the leuco compound may be effected by exposure to air or by the action of nitrous acid employed for the diazotization.  Following the nitrous acid treatment a weak alkaline treatment may be applied to complete the coupling. Specified diazotizable amines are primary amines of the benzene, naphthalene, carbazole and anthraquinone series and particularly the amines used according to the processes of Specifications 310,779, [Class 15 (ii), Dyeing, Processes &c. for], 396,412, 396,429, 396,430, and 396,431. Specified coupling components are arylamides of oxycarboxylic acids of the benzene, naphthalene or carbazole series, e.g. the m-nitranilide of 2 : 3-oxynaphthoic acid, and diacylacetyl derivatives of aromatic diamines.  Specified vat dyes are Algol brilliant green BK, 5 : 7 : 5<1> : 7<1>-tetrabromindigo and those listed in Specification 355,363.  The amines or coupling components may be applied as aqueous dispersions, e.g. such as are obtainable by the use of the dispersing agents of Specifications 219,349, 224,925, 242,393, 242,711, 269,960, 273,819, 273,820, 322,737, or 323,788, [all in Class 15 (ii), Dyeing, Processes &c. for], and dispersion of phenolic coupling components may be facilitated by the presence of small quantities of alkali.  The various components may be applied by dyeing, padding, printing or stencilling, and pattern effects are obtainable by local application of components, e.g. by uniform application of the amine and coupling component and local application of the leuco compound.  In addition to cellulose ester or ether materials, animal fibres, cotton or regenerated cellulose artificial silk may be coloured by the process.  The following examples are specified. (1) The dyestuff Algol brilliant green BK, wetted with methylated spirit and vatted at 60 DEG  C. in an aqueous liquor containing sodium hydrosulphite and monoethanolamine, is added to the dyebaths together with a turkey red oil dispersion of 2-chloraniline, a caustic soda solution of diacetoacetyl-o-tolidine, and glucose; a cellulose acetate yarn is entered at 30--40 DEG  C., the temperature is raised during \ba1/2\be hour to 75 DEG  C. and so maintained for 1 hour, whereafter the yarn is rinsed and treated for \ba1/2\be hour in a bath at a temperature not above 15 DEG  C. containing sodium nitrite and acetic acid, again rinsed and treated for \ba1/4\be hour in a cold bath containing soda ash and soap, the temperature being raised slowly to 75 DEG  C. and so maintained for \ba1/2\be hour; on rinsing and drying a brilliant emerald green dyeing is obtained.  (2) The dyestuff 5 : 7 : 5<1> : 7<1>-tetrabromindigo, vatted at 60 DEG C. in an aqueous liquor containing sodium hydrosulphite, monoethanolamine and turkey red oil, is added to the dyebath together with a turkey red oil dispersion of 2 : 5-dichloraniline, a caustic soda solution of diacetoacetyl-o-tolidine and glucose; degummed silk yarn is entered into the bath and the temperature is raised slowly to 75 DEG  C. and so maintained for 1\ba1/2\be hours, whereafter the yarn is rinsed and treated for \ba1/4\be hour in a bath containing sodium nitrite and acetic acid, again rinsed and further treated as in (1) above.  According to the Provisional Specification the vat dyes may be applied by the process of Specification 262,506, [Class 15 (ii), Dyeing, Processes &c. for].