Leuco vat-dye preparations in granule form
AssigneeBASF SE
InventorsManfred Gang, Rudolf Kruger, Peter Miederer, Harald Schluter, Peter Schultz, Manfred R. Wolf
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Abstract
Granular leuco vat-dye preparations containing, as essential components, leuco vat-dye, reducing agents and alkaline metal hydroxide, and the production of said preparations and their use in dyeing cellulose-containing textile materials.
Claims11
A leuco indigo preparation in granule form, consisting essentially of leuco indigo or leuco forms of indigo derivatives, hydrosulfite and alkali metal hydroxide,
- wherein said leuco indgo preparation comprises about <4% by weight of unreduced indigo wherein said granules are mainly spherical particles having a mean particle size from 0.1 to 2 mm.
A method of stabilizing dry hydrosulfite against self-ignition, which comprises spray granulating an aqueous hydrosulfite solution together with a leucoindigo solution with exclusion of oxygen in such a weight ration that the resulting granules comprises hydrosulfite in an amount <50% by weight of hydrosulfite.
Dependencies are inferred from the claim text.