Use of biscationic acid imide and acid imide derivatives whose anion is the stoichiometric equivalent of one or more organic or inorganic, mixed or non-mixed anions, the compounds also being able to exist as mixed crystals with different cations, individually or in combination, as charge controllers for toners and developers employed for electrophotographic copying or multicopying of originals and for printing electronically, optically or magnetically stored data or in color proofing, and as charge controllers for powders and powder paints.