GB245587A - Improvements in and relating to dyes and dyeing - Google Patents

Abstract

245,587. Jones, J. I. M., Wylam, B., Morton, J., and Morton Sundour Fabrics, Ltd. July 12, 1924. Grant of Patent refused. Leuco-compounds of vat-dyes, alkylsulphuric esters of.-Alkylsulphuric halides are caused to act on leuco-compounds of vat-dyes, particularly those of the anthraquinone series. The products form stable solutions in water or dilute alkalies; fibres such as cotton, wool, silk, and artificial silk can be dyed or printed with these solutions, the shade of the parent dyestuff being then developed by treatment with an acid oxidizing agent such as an acid solution of ferric chloride. The following examples are given :-(1) leucoflavanthrone (obtained by acidification of a flavanthrone vat, filtering, washing, and drying in absence of air) is treated with methylsulphuric chloride in a mixture of carbon disulphide and pyridine; (2) leuco-indanthrone is treated with methyl- or ethyl-sulphuric chloride in chlorbenzene and pyridine; (3) leuco-anthraquinone-2 :1- naphthacridone (Caledon Red BN) is treated with methylsulphuric chloride in pyridine: (4) material is printed with a thickened caustic soda solution of the methysulphuric ester of leuco-flavanthrone, steamed, and treated with acid ferric chloride solution. Alkylsulphuric esters may be similarly obtained from indigo-white and other leuco compounds of vat-dyestuffs. Specification 248,802 is referred to.