A charging device for use in an image forming apparatus is disclosed which charges an object to be charged by contacting a conductive charging member with the surface of the object and then applying a voltage across the charging member and the object, wherein at least a contact portion of the charging member comprises a conductive material having a hygroscopic degree of 0.2% or less.
An electrophotographic recording apparatus having a charging roller with a surface layer having a mixture of a resin and a hardener. The surface layer includes at least 10%, but less than 30%, by weight of the surface layer, of the hardener. This specific surface layer composition prevents the photosensitive drum, which is in contact with the charging roller, from becoming excessively charged. Furthermore, the amount of toner that adheres to the charging roller is reduced by circumferentially rotating the charging roller at a rate faster than the photosensitive drum.
A charging device includes a rotatable elastic charging roller, contactable to a member to be charged, for electrically charging the member to be charged. The charging device also includes a DC voltage source for applying a DC voltage to the charging roller. The voltage source is capable of controlling the width of a variation of the DC voltage, the variation being caused by passage of a deformed portion of the charging roller, resulting from contact between the member to be charged and the charging roller, by a charging region of the charging roller for the member to be charged, to be not more than 1%.
