| 摘要 |
PROBLEM TO BE SOLVED: To prevent toner from being stuck to a developing sleeve and hindering development even in the case of using toner for low-temperature fixing. SOLUTION: In this reversal developing system developing device 4, the layer pressure of two-component developer consisting of toner and carrier laminated on the surface of a rotated developing sleeve 9 is regulated by a doctor 12 consisting of a conductor, and the potential of the sleeve 9 is set to potential having the same polarity as the charge polarity of the toner, and the toner is moved toward an electrostatic latent image on a photoreceptor 1 by electric field formed between the sleeve 9 and the electrostatic latent image on the photoreceptor 1 so as to be stuck to the electrostatic latent image. The doctor 12 is grounded. Carrier whose average particle diameter is <=50 μ and whose electrified amount after it is stirred with the toner is >=15 μc/g is used as the carrier. In the reversal developing system or normal developing system developing device, it is conceivable to apply voltage having the reverse polarity to the charge polarity of the toner to the doctor 12 by a power source. |
