To prevent an irregularity in an image in a solid image part and in a half tone image part.

Silica and titanium oxide are externally added to toner particles under such conditions that the add amt. of silica is 0.5 to 3.5 wt.%, the add amt. of titanium oxide is 0.1 to 2.0 wt.%, and the total and amt. of silica and titanium oxide is 1.0 to 5.0 wt.% to the total weight of the toner particles and the relation between the add amts. of silica and titanium oxide is represented by 1< (add amt. of silica)/(add amt. of titanium oxide) ≤5.