GB190304667A - Improvements in, and relating to, Printing on Vegetable Fibre and Means therefor - Google Patents

Abstract

4667. Lake, H. H., [Oehler, K.]. Feb. 27. Dyeing.-Relates to the printing, by means of resists, of white and coloured designs upon cotton goods dyed with p - nitraniline red or other developing-colour, and consists in using as resists hydrazine, hydroxylamine, and their derivatives, such as phenylhydrazine, tolylhydrazine, alpha and #- naphthylhydrazine, phenylhydroxylamine, benzylbydroxylamine, phthalylhydroxylamine, and their salts, their sulphoconjugated derivatives, and the salts of the latter. These bodies are either finely ground or dissolved into suitable thickenings, while, for coloured resists, suitable colours and fixing-agents must be added. There are three methods of carrying out the invention :-(1) On insoluble azo colours developed in the fibre, for example, the #-naphthol combinations of diazotized bases, such as aniline &c., a white resist is formed of phenylhydrazine sulphonic acid, water, ammonia, and ammonium sulphocyanate. This is mixed with a thickening formed of wheat starch, British gum, tragacanth, and water. In this case, the goods are padded with #-naphthol, dried, printed with the resist, dried, developed by diazo - pnitraniline, rinsed, passed through hot water, soaped, rinsed, given a chlorine bath, and again rinsed and dried. A stock of resist may be made, consisting of the hydroxylamine, or hydrazine, and water and thickening, and this is neutralized with ammonia and diluted before used. The reserving power is increased by adding a solution of glue to the thickening, or tannic acid neutralized with ammonia to the resist colour. Directions are also given for making coloured resists for use with basic colours, such as benzoflavine, anramine, thioflavine, benzal, methylene blue, navy blue, fast grey &c. ; and also for coloured resists for use with mordant colours. (2) On the so-called combination method described in Specification No. 5122, A.D. 1897. In this case, the cotton is dyed with toluylene orange G or R, with diazo orange, or with benzonitrol-bordeaux, or with a mixture, dried, and printed with the white resist, after which it is dried, cooled, and padded with a suitable diazo solution. Modifications may be made by simultaneously printing the white resist with a coloured resist, or with white or coloured discharges, directly-dyeing colouring-matters or aniline black or logwood black. (3) On colours which are diazotized upon the fibre and then developed with different compounds, such as azo-mauve, diamiueblack, primuline, &c. By using the white or coloured resists, the following effects may be obtained :-(a) a resist primuline yellow under primuline red ; (b) coloured resists on brick red (obtained with primuline) ; (c) green resists on primuline red ; and (d) coloured resists on primuline brown.