Charging device with contactable charging means and an image forming apparatus having the charging means and a detachable process unit

摘要

A charging device for charging a moving member to be charged includes charging device for being contacted to the member to be charged to charge the member; a voltage source for applying a vibratory voltage to the charging device; wherein the charging device includes a first layer contactable to the member to be charged, a second layer adjacent thereto wherein the first layer is a dielectric layer having a volume resistivity larger than that of the second layer.