Ciba-geigy Corporation

Nitya G Podder

Hans Mollet

Horst H Jager

Suresh C Agarwal

The invention relates to a process for the preparation of a storage stable aqueous formulation of anionic dyes, which process comprises treating the aqueous dye solution and/or dispersion with a polymeric anion exchanger, simultaneously and/or subsequently subjecting the resin-bonded dye to a mechanical wet grinding, in the presence of a nonionic dispersant, and adding to the resultant aqueous dispersion the assistants customarily present in the liquid dye formulations. The process makes it possible to precipitate anionic dyes in virtually quantitative yield from aqueous solution and to prepare storage-stable dye dispersions.

Process for the preparation of storage stable aqueous formulations of

The invention relates to dyestuff preparations comprising water, a water-insoluble or sparingly water-soluble dye, a dispersant, a humectant, and optionally further additives, wherein said humectant is a compound of the formula I ##STR1## wherein R is a C.sub.1 -C.sub.16 alkyl group which is unsubstituted or substituted by OH, CN, halogen or --N(C.sub.1 -C.sub.4 alkyl).sub.2, and R' is hydrogen or the --CH.sub.2 --CHOH--CH.sub.2 OH group. These preparations are suitable for use in aqueous or aqueous-organic dye liquors or printing inks or also for obtaining printing pastes. After partial or complete dehydration they are also very readily redispersible.

Liquid dyestuff preparations

The readily dispersible dye preparations contain water, one or more dyes insoluble or difficultly soluble in water, a nonionic dispersing agent and optionally further additives, and as anionic dispersing agent:

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Duggingen, Switzerland

Nitya G Podder