Water-based liquid color containing thermostable dispersion additives for the coloring poly(meth)acrylates

An aqueous colorant preparation, comprising:

• a) from 1% to 49% by weight of a dispersing additive having a mass loss in dried form of not more than 15% by weight, in isothermal thermogravimetric analysis at 260° C. for 60 min;
• b) from 0.5% to 50% by weight of a pigment or of a pigment mixture;
• c) from 0% to 50% by weight of an assistant;
• and
• d) from 0% to 98.5% by weight of water,
• wherein the portions by weight of components a) to d) add up to 100% by weight, and the pigment b) is at least one selected from the group consisting of a diazo dye, perylene, an anthraquinone, an anthrapyrimidine, perinone, Thermoplast Red® 454, Macrolex Yellow® G, zinc chromate, cadmium sulphide, chromium oxide, an ultramarine pigment, a metal flake, BaSO4, Sandoplast® Red G, and Solvaperm® Red G.