TONER

摘要

PROBLEM TO BE SOLVED: To embody the miniaturization and simplification of a device, the adaptation to a development method which allows a cost reduction and high image quality of high densities an low ground fogging by incorporating specific wax composed of at least polyethylene(PE) into a binder resin. SOLUTION: The wax composed of at least the PE is incorporated into the binder resin of the toners at 5 to 10 pts.wt. per 100 pts.wt. binder resin. The wax is formed by a thermal decomposition method. The recover rate in the case of washing for one hour with toluene at 25 deg. is >=95% and the softening point of the wax is 80 to 140 deg.. The needle penetration rate at 25 deg.C is <=8. The toners are 0.3<=(St-Sb)/(Sa* W / 100)<=0.7 when the specific surface area of the toners is defined as St(m<2> /g), the specific surface area of the toner base material as Sb(m<2> /g), the specific surface area of external additives as Sa(m<2> /g) and the addition amt. of the external additives as W(wt.%). A release agent, a flow property assistant, such as powder of org. materials, electrostatic charge assistant and cleaning assistant may be incorporated at need into the toners.