GB571931A - Manufacture of new sulphur colours - Google Patents

Abstract

Sulphur dyestuffs are made by the interaction, with heating, if desired, of a polycyclic aromatic hydrocarbon and the aluminium chloride-sulphur monochloride complex of constitution AlCl3.2S2Cl2. Sulphur monochloride may be used with the complex. The crude reaction products may be purified by extraction with dilute alkali, with subsequent oxidation, if necessary. Free sulphur may be removed by extraction with carbon disulphide. The dyes are converted to their soluble leuco compounds by heating with sodium sulphide solutions, e.g. by heating with sodium sulphide melted in its own water of crystallization. They may be used to dye cotton and acetate or viscose rayon and wool, silk and nylon fibres have been dyed with them. In the examples, the following compounds are converted into sulphur dyestuffs by treatment with the complex under varying conditions: acenaphthene, perylene, pyrene, phenanthrene, retene and fluorene. In one example, the reaction is effected in a medium of carbon tetrachloride. The complex used in the examples is made by heating aluminium chloride and sulphur monochloride together at 90-95 DEG C. for 36 hours. The Specification as open to inspection under Sect. 91 comprises also the reaction of polycyclic aromatic compounds in general with any aluminium chloride-sulphur monochloride complex, and contains additional examples in which polybenzyl and gum rosin are reacted with the complex, AlCl3.2S2Cl2. This subject-matter does not appear in the Specification as accepted.