Leuco-sulphuric esters of vat dyes and anthraquinone dye intermediates and salts thereof are made by reacting the corresponding leuco compound, or a metal salt of the corresponding leuco compound, or a complex compound comprising the metal salt of the corresponding leuco compound, in the presence of an organic amide as defined below, with or without the addition of diluents, with sulphur trioxide or with an addition compound of sulphur trioxide with an organic amide or tertiary base, or with any substance known to be capable of forming sulphuric esters from vat dyestuffs in the presence of metals, or from leuco compounds, or metal salts thereof, or complex compounds comprising the metal salts thereof. The amides are compounds of the formula R.CO.NR1R2 or R.SO2.NR1R2, where R stands for a hydrogen atom or an organic radical or, when the compound is of the formula R.CO.NR1R2, for a hydrogen atom and R1 and R2 stand for hydrocarbon radicals or substituted hydrocarbon radicals which may be the same or different and which may be connected with each other to form together with the nitrogen atom a closed ring. Amides specified are dimethylformamide, diethylformamide, dimethylacetamide, formylpiperidide, tetramethylurea, and diethyltoluenesulphonamide. Alternatives to sulphur trioxide specified are the addition compounds thereof with dimethylformamide or picoline, or an ester of chlorsulphonic acid. Metals specified are zinc, iron, and copper, and catalysts for the formation of the metal salt specified are potassium ethyl sulphate, sodium - 2 - naphthol - 6 - sulphonate, calcium naphthalene-2.6-disulphonate, sodium-naphthalene-sulphonate, ferric chloride, and magnesium chloride. In examples, the following substances are converted to their leuco compound metal salts (if not already in that form) and then to their leuco-sulphuric esters, using amides of the type defined: (1) 1.4-dibenzoylaminoanthraquinone; (2) 16.17-dimethoxydibenzanthrane; (3) 5.51 - diethoxythioindigo; (4) 2 - (1 - amino - 2 - anthraquinonyl) - antraquinone-21.31-oxazole; (5) 3-chloro-2-acetylamino - anthraquinone; (6) 2 - chloro-anthraquinone; (7) anthraquinone; (8) 9.10-dihydroxyanthracene; (9) leuco-indigo; (10) leuco - 16.17 - dimethoxydibenzanthrone; (11) 4.10 - dibromoanthanthrone; (12) 16.17 - dimethoxydibenzanthrone; (13) 1 : 11 : 4 : 111 - trianthrimide - 2.21.3.211 - dicarbazole; (14)2 - (1 - amino - 2 - anthraquinonyl) - anthraquinone - 21.31-oxazole; (15) anthraquinonyl-1-urethane; (16) 1.11-dianthrimide; (17) leuco-16.17-dimethoxydibenzanthrone; (18) leuco-flavanthrone. Specifications 186,057, 274,156, [both in Class 2 (iii)], 633,478 and 633,480, [both in Group IV (c)], are referred to.ALSO:Leuco-sulphuric esters of vat dyes and anthraquinone dye intermediates and salts thereof are made by reacting the corresponding leuco compound, or a metal salt of the corresponding leuco compound, or a complex compound comprising the metal salt of the corresponding leuco compound, in the presence of an organic amide as defined below, with or without the addition of diluents, with sulphur trioxide or with an addition compound of sulphur trioxide with an organic amide or tertiary base, or with any substance known to be capable of forming sulphuric esters from vat dyestuffs in the presence of metals or from leuco compounds, or metal salts thereof, or complex compounds comprising the metal salts thereof. The amides are compounds of the formula R.CO.NR1R2 or R.SO2.NR1R2, where R stands for a hydrogen atom or an organic radical or, when the compound is of the formula R.CO.NR1R2, for a hydrogen atom and R1 and R2 stand for hydrocarbon radicals or substituted hydrocarbon radicals which may be the same or different and which may be connected with each other to form together with the nitrogen atom a closed ring. Amides specified are dimethylformamide, p diethylformamide, dimethylacetamide, formylpiperidide, tetramethylurea, and diethyl-p-toluenesulphonamide. Alternatives to sulphur trioxide specified are the addition compounds thereof with dimethylformamide or picoline, or an ester of chlorsulphonic acid. Metals specified are zinc, iron, and copper, and catalysts for the formation of the metal salt specified are potassium ethyl sulphate, sodium - 2 - naphthol - 6 - sulphonate, calcium naphthalene - 2 : 6 - disulphonate, sodium b -naphthalene-sulphonate, ferric chloride, and magnesium chloride. In examples, the following substances are converted to their leuco compound metal salts (if not already in that form) and then to their leuco-sulphuric esters, using amides of the type defined: (1) 1.4-dibenzoylaminoanthraquinone; (2) 16.17-dimethoxydibenzanthrone; (3) 5.51-diethoxythioindigo; (4) 2-(1-amino-2-anthraquinonyl)-anthraquinone - 21.31 - oxazole; (5) 3 - chloro-2 - acetylamino - anthraquinone; (6) 2 - chloroanthraquinone; (7) anthraquinone; (8) 9.10-dihydroxyanthracene; (9) leuco-indigo; (10) leuco - 16.17 - dimethoxydibenzonthrone; (11) 4.10-dibromoanthanthrone; (12) 16.17-dimethoxydibenzanthrone; (13) 1 : 11 : 4 : 111 - trianthrimide - 2.21.3.211 - dicarbozole; (14) 2-(1 - amino - 2 - anthraquinonyl) - anthraquinone-21.31-oxazole; (15) anthraquinonyl-1-urethane; (16) 1.11-dianthrimide; (17) leuco-16.17-dimethoxydibenzanthrone; (18) leuco-flavanthrone. Specifications 186,057, 274,156, [both in Class 2 (iii)], 633,478 and 633,480 are referred to.