Fitzpatrick, Cella, Harper & Scinto
Image forming apparatus with charging member supplied with first and second DC voltages of opposite polarities
 An image forming apparatus includes an image bearing member; a charging member for charging the image bearing member at a charging position, the charging member being contactable to the image bearing member; wherein the charging member is adapted to be supplied with a first DC voltage of a predetermined polarity for forming an image on the image bearing member and contains ion conduction material, and wherein the charging member is adapted to be supplied with a second voltage of a polarity opposite from the predetermined polarity when such an area of the image bearing member as is going to a non-image area of the image bearing member is at the charging position. 
Canon Kabushiki Kaisha
G
G03G
inventional
Osamu Sorin Hiroshi Nobuyuki
Watanabe Den Matsumoto Kume