Improvements in the Manufacture of Sulphur Dye-stuffs.

摘要

17,805. Meyenberg, A., and Clayton Aniline Co. Aug. 17. Dyes, artificial.-Substantive sulphur dye-stuffs, such as a black dye from the dinitrophenol (OH: NO2 : NO2=1 : 2 : 4), are obtained practically pure, without the use of sodium sulphide or sulphur, by treating its sodium salt with sulphuretted hydrogen, pure or mixed with air. The sodium salts of dinitrocresol, of diphenylamine derivatives obtained by means of dinitrochlorbenzene or otherwise, and of other compounds, also yield dyes on similar treatment, though not necessarily the same as result from the action of sodium sulphide and sulphur. For example, sulphuretted hydrogen is passed through a boiling aqueous solution of sodium dinitrophenolate, in a vessel provided with a reflux and a stirring arrangement, until the colour of the solution no longer changes. The water is then distilled off until the residue thickens. The latter is kept until no more colour forms, and is then heated to dryness and powdered for use. The addition of compounds which influence the colour of the products obtained in other sulphuration methods, produces, to some extent, the same effects in the present one.