| 摘要 |
PROBLEM TO BE SOLVED: To prevent the transfer of toner stuck to a non-image part to an intermediate transfer body and to obtain high image quality by applying a opposite polarity of an electric charge to that of the toner to a toner image on an image carrier, before the toner stuck on the image carrier is transferred to the intermediate transfer body. SOLUTION: A negative charge is uniformly applied to a photoreceptor 1 by a scorotron electrifier 2 connected to a negative voltage source. A developer is carried to the surface of the photoreceptor 1 by the rotation of the developing roll of a developing device. A negative developing bias voltage is applied to the developing roll and the toner is stuck to the surface of the photoreceptor 1, to make an electrostatic latent image visualizable. At this time, an electrifier 5 connected to a positive voltage source uniformly applies a positive charge, the opposite polarity to that of the toner, to all the toner. The value of the electrified quantity of the toner stuck to the non-image part is drastically changed when the charge is applied and the attracting force of the toner whose polarity is changed to the photoreceptor 1 becomes strong to prevent the transfer of the toner to an intermediate transfer drum 6. |
