Aqueous formulation containing (A) at least one pigment or at least one dyestuff, (B) at least one dispersant selected from (B1) copolymers of at least one ethylenically unsaturated C4-C10-dicarboxylic acid and at least one C4-C20-olefin and their respective alkali metal salts and (B2) aromatic sulfonic acids and their respective alkali metal salts.(C) at least one chelating agent selected from MGDA, GLDA, IDS and citric acid and their respective ammonium and alkali metal salts. (D) water, wherein the concentration of the pigment (A) or dyestuff (A) is in the range of from 5 to 500 ppm, referring to the total aqueous formulation, and wherein the weight ratio of dispersant (B) to the pigment (A) or dyestuff (A), respectively, is in the range of from 1:5 to 3:1.