NEW SUSTAINABLE RANGE OF DYESTUFFS FOR TEXTILE AND PAPER DYEING

摘要

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.

主权项

1. A process for manufacturing a dyestuff comprising:
(i) Providing vegetal biomass; (ii) Pretreating said vegetal biomass with an aqueous alkaline medium and/or with an amino and/or polyamino compound, at an elevated temperature; (iii) Mixing pretreated vegetal biomass with at least one sulfurization agent selected from the group consisting of sulfur, sulfide, and polysulfide; (iv) Heating said mixture to a temperature of from 120° C. to 350° C. for at least 2 hours; (v) Dissolving the mixture in aqueous medium and optionally removing undissolved solid particles.