ELECTROPHOTOGRAPHIC TONER

摘要

PROBLEM TO BE SOLVED: To obtain an electrophotographic toner attaining rapidly the saturation quantity of electric charges at the time of kick-off of electrostatic charge, having a very high uniformity in the distribution of the quantity of electric charge and giving a fog-free high quality image by adding a specified amt. of electrically conductive fine particles and a specified amt. of fine silica particles to the surfaces of spherical colored resin particles contg. a colorant in a bonding resin. SOLUTION: A soln. contg. a colorant and a bonding resin in an org. solvent is mixed with an aq. medium under stirring, the org. solvent is removed and particles dispersed in the aq. medium are separated as dry powder. Electrically conductive fine particles and fine silica particles are then added to the surfaces of the resultant spherical colored resin particles contg. the colorant in the bonding resin. It is especially preferable that 0.05-3wt.% hydrophobic electrically conductive fine particles having 5-500nm average diameter of primary particles and 0.05-3wt.% fine silica particles are added to the resin particles. The objective electrophotographic toner giving a satisfactory image is obtd.