摘要 |
A liquid preparation of an anionic dye of the disazo class, which preparation contains the disazo dye, which in the form of the free acid corresponds to the formula <IMAGE> +TR <IMAGE> dissolved in a solvent mixture which is miscible with water in any proportion and which consists of N,N,N',N'-tetramethylurea, at least one alkylene glycol ether and water, and alkyl- or alkanolamine in an amount sufficient to bring the pH value of the liquid preparation to 6.5 to 8.5, the dye being in the form of alkyl- or alkanolamine. This novel liquid preparation is a concentrated true solution which is stable in storage over several months at temperatures of between about -10 DEG C. and +60 DEG C., and which is miscible with cold and warm water in any proportion. It is suitable in particular for dyeing and printing paper, including semi-cardboard and cardboard, the dyeing of these materials being possible, for example, in the pulp, or by brushing or immersion.
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