Patent GB-365170-A (GB)
Title: Improvements in the colouration of materials made of or containing cellulose derivatives
IPC: D06P3/82
Filed: 1930-10-16
Abstract: In the colouration of cellulose esters and ethers, an aqueous dispersion of a relatively insoluble dyestuff or colouring material, prepared by means of a sulphonated condensation product of an alcohol containing at least eight carbon atoms with an aromatic carbocyclic or heterocyclic compound, is employed.  The condensation of the aromatic compound with the higher alcohol may be effected by means of chlorsulphonic acid, oleum or concentrated sulphuric acid, in which case sulphonation takes place simultaneously, but the sulphonation may be effected as a separate step before or after the condensation. Benzene, naphthalene and derivatives thereof containing alkyl, hydroxy, halogen or sulphonic groups are mentioned as suitable aromatic compounds that may be used and the following alcohols are specified: secondary octylalcohol, n-octodecylalcohol, cerylalcohol, myricylalcohol, n-dodecylalcohol and cetylalcohol. Carbazol is mentioned as a suitable heterocyclic compound.  In one example, a mixture of naphthalene and cetyl alcohol is simultaneously sulphonated and condensed with chlorsulphonic acid. The resulting product is used in further examples for dispersing 2 : 4-dinitro-4<1>-hydroxydiphenylamine, which dyes cellulose acetate fabric a yellow shade, and for preparing a dye bath, for dyeing a mixed fabric of wool and cellulose acetate, containing benzene-azo-1-phenyl-3-methyl-5-pyrazolone and Azorhodine 2 G. The dispersions of the colouring materials may be prepared by mixing or grinding the constituents, but the colouring materials may also be formed, liberated or precipitated in the presence of the dispersing agent.  Auxiliary substances, e.g. those specified in Specifications 242,711 and 269,960, [both in Class 2 (iii), Dyes &c.], may be added. The invention may be applied to any cellulose ester, e.g. cellulose formate, propionate or butyrate or to the products obtained by treatment of alkalized cellulose with esterifying agents (e.g. the product known as immunized cotton obtained by means of p-toluenesulphochloride) or to any cellulose ether, e.g. methyl, ethyl, or benzyl cellulose or the corresponding condensation products of cellulose with glycols or other polyhydric alcohols.  Their mixed fabrics containing cellulose esters or ethers are used, the silk, wool, cotton, &c. may be dyed before, after or together with the cellulose ester or ether portion.  Any colouring material having an affinity for the fibres may be used, e.g. those mentioned in Specifications 219,349, 220,505, 224,681, 227,183, 237,943, 239,470, 253,978, 263,260, 283,081, 283,253, 299,349, 305,560, 306,981, 310,827, and 311,433, [all in Class 15 (ii), Dyeing, Processes &c. for].  In the case of dyeing for the azoic process, the base may be first applied, diazotized and then developed, or the developed component may be applied first and the colour formed by treatment with a diazo solution, or the base and developer components may be applied separately or together and the colour produced by subsequent diazotization.  Specification 224,925, [Class 2 (iii), Dyes &c.], also is referred to.