Process for the preparation of vat dyes from brominated dibenzanthrone and 1-aminoanthraquinone
AssigneeCiba-Geigy Corporation
InventorWerner Brenner
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Abstract
There is disclosed a process for the preparation of vat dyes that dye cellulosic material in a grey or black shade of good fastness properties. The process comprises brominating dibenzanthrone and reacting the brominated reaction product with 1-aminoanthraquinone in a single step.
Claims15
A process for the preparation of vat dyes that are reaction pro of brominated bidenzanthrone with 1-aminoanthraquinone, which process comprises brominating dibenzanthrone, in an inert organic solvent, in the absence of sulfuric acid, and reacting the solution of the brominated intermediate with 1-aminoanthraquinone, without isolation of the brominated dibenzanthrone.
Dependencies are inferred from the claim text.