Abstract: Water-soluble black trisazo dyestuffs of the general formula I ##STR1## wherein R denotes hydrogen, alkyl having 1 or 2 carbon atoms, alkoxy having 1 or 2 carbon atoms, acylamino having 2 or 3 carbon atoms or carboxamide and n denotes a number from 0 to 2.5 are suitable for the preparation of recording fluids.

Abstract: The aqueous dyestuff formulation of an tetrakisazo direct dyestuff which is stable to alkali and contains at least one aromatic hydroxyl group and/or enol group and at least one group conferring solubility in water, or a mixture of such azo direct dyestuffs, is characterized in that it has a pH value equal to or greater than 12 and is prepared by mixing an azo direct dyestuff which is stable to alkali, water and a tertiary alkali metal phosphate and/or alkali metal metasilicate and/or alkali metal hydroxide, and by choosing the proportions such that the dyestuff formulation contains 5 to 50% by weight of dyestuff and has a pH value equal to or greater than 12. The dyestuff formulation is used, after dilution with water, for dyeing and printing natural or synthetic materials containing hydroxyl groups.