Image-forming apparatus including first and second charging members with a target potential charging feature

摘要

According to the present invention, in an image-forming apparatus having at least two chargers for charging a rotating image carrier, in accordance with change in bias applied to a second charger disposed on the downstream side in a rotational direction of the image carrier, the bias applied to a first charger disposed on the upstream side is changed. Thereby, the electric power required for the charging is reduced.