Abstract: The present invention relates to a method for treating at least one protein substrate comprising at least one dyeing step, wherein in the at least one dyeing step at least one dyeing composition comprising at least one sulfur dye is used. The present invention further relates to a hair colorant comprising at least one sulfur dye. It also relates to a protein substrate that has been treated with the method according to the invention or the hair colorant according to the invention. The present invention further relates to the use of a dyeing composition comprising at least one sulfur dye for dyeing at least one protein substrate.

Abstract: The invention refers to the manufacturing of a novel group of sulfur dyes in which are used, as raw material, different kind of natural “biomass”, usually existing in the nature, and transforming them into soluble dyestuffs, capable to dye textile fibers, preferably cellulose fibers and derivatives, as cotton, viscose, paper, tencel, with high strength and fast color properties. For this purpose, the concept “Biomass”, is defined as the residual product obtained from the usual human crop activities, in agricultural and forestry sectors.

Abstract: The invention refers to the manufacturing of a novel group of sulfur dyes in which are used, as raw material, different kind of natural “biomass”, usually existing in the nature, and transforming them into soluble dyestuffs, capable to dye textile fibers, preferably cellulose fibers and derivatives, as cotton, viscose, paper, tencel, with high strength and fast color properties. For this purpose, the concept “Biomass”, is defined as the residual product obtained from the usual human crop activities, in agricultural and forestry sectors.

Abstract: The invention refers to the manufacturing of a novel group of sulfur dyes in which are used, as raw material, different kind of natural “biomass”, usually existing in the nature, and transforming them into soluble dyestuffs, capable to dye textile fibres, preferably cellulose fibres and derivatives, as cotton, viscose, paper, tencel, with high strength and fast colour properties. For this purpose, the concept “Biomass”, is defined as the residual product obtained from the usual human crop activities, in agricultural and forestry sectors.

Abstract: The invention refers to the manufacturing of a novel group of sulfur dyes in which are used, as raw material, different kind of natural “biomass”, usually existing in the nature, and transforming them into soluble dyestuffs, capable to dye textile fibres, preferably cellulose fibres and derivatives, as cotton, viscose, paper, tencel, with high strength and fast colour properties. For this purpose, the concept “Biomass”, is defined as the residual product obtained from the usual human crop activities, in agricultural and forestry sectors.

Abstract: Azo dyes containing sulphur dye entities as a constitutional component are dyes of valuable properties, in particular for the dyeing of leather.

Abstract: New sulfur dyes comprising in their preparation at least one sulfur dye intermediate of the formula I ##STR1## wherein R and R.sub.1 are independently nitro, nitroso or amino, are produced by including in their preparation at least one modifying agent selected from the group of: A) an aldehyde; B) urea; C) a benzoquinone or naphthoquinone; and D) monoethanolamine or by treating an already prepared sulfur dye involving such an intermediate in its preparation, with at least one aldehyde, benzoquinone or naphthoquinone or with monoethanolamine.

Abstract: A cationic dye (S.sub.K) comprising at least one quaternary ammonium group or protonated or protonizable tertiary amino group and at least one chromophoric radical, wherein the chromophoric radical is the radical of an optionally (pre)reduced sulphur dye, its precursor (S.sub.K1) containing a cationic group which is a secondary amino group of basic character, which is optionally protonated but does not contain an acid group in a substituent of this cationic group, or a mixture thereof and desolubilized derivatives thereof or of their non-quaternized and non-tertiary precursors, which in standardized form are usable as pigments.