The present invention relates to a pigment preparation that comprises, as component (A), 2,4,5,7-tetraaminopyrimido[5,4g]pteridine of formula, as component (B), a phosphate compound, and optionally, as component (C), further additives, to a process for the production thereof and to the use thereof for colouring high molecular weight organic material and in the production of printing colorants, printing pastes or printing inks.