| abstract |
The toner load in a container is concentrated in the vicinity of the developing roller as it is, the toner does not flow and stays in the vicinity of the layer thickness regulating member, and the density unevenness due to poor follow-up at the time of fixing to the layer thickness regulating member or full solid printing. Providing no developing device. In a developing device including a developing roller, a supply roller, and a layer thickness regulating member, the toner used in the vertical developing device has a vertical structure having a toner replenishing mechanism on the upper side, and the toner used in the vertical developing device contains wax. A toner for one-component development, which contains at least a wax-containing resin, a color material, and an external additive, and a nip width front end a where the layer thickness regulating member 104 and the developing roller 103 are in contact with the developing roller 103 The nip width tip b between the supply rollers 105 satisfies a relationship of 0.8 <| ab− <2.0 (mm). [Selection] Figure 1 |