ELECTROSTATIC CHARGE IMAGE DEVELOPING TONER AND IMAGE- FORMING METHOD

摘要

PROBLEM TO BE SOLVED: To provide a toner, having superior chargeable stability and capable of obtaining an image high in image density and definition even for long-term use. SOLUTION: In the electrostatic charge developing toner having toner particles, containing at least binder resin and coloring agent and having external additives, the average circularity of the toner particles is >=0.960 and at least titanium oxide fine particles and silica fine particles are externally added to the toner particles. The number isolation rate of titanium oxide fine particles (Yt) on the toner particle surfaces ranges from 1.00 to 50.00%, and the number isolation rate of silica fine particles (Ys) is in the range of 0.01 to 4.00%, with Yt>Ys.