| 摘要 |
According to one embodiment, there is provided, a developing agent including a toner containing a toner particle containing a coloring agent, an amorphous polyester, a crystalline polyester having an endothermic peak temperature T1 measured by a differential scanning calorimeter, and an ester wax having an endothermic peak temperature T2 measured by a differential scanning calorimeter, and an additive composed of an inorganic oxide particle added onto the surface of the toner particle. The additive has a volume average particle size of from 80 to 200 nm. Also, the developing agent is satisfied with the following expression (1). 15(° C.)≦̸|T2−T1|≦̸50(° C.)  (1) |
