Toner for electrostatic development, charge controlling agent for the toner and process for producing the same

摘要

A positively charging dry toner for developing an electrostatic latent image including a nigrosine dye or nigrosine pigment containing 500 ppm or less nitrobenzene and 800 ppm or less aniline as a charge controlling agent. The dye or pigment is prepared by dispersing the nigrosine dye or nigrosine pigment obtained by an usual method in a solvent, adding an oxidizing agent such as bleaching powder to the solvent dispersion to conduct oxidation treatment and, if necessary, removing the solvent by steam distillation.