Charging device, process cartridge and image forming apparatus

摘要

A charging device, suitable for use in an electrophotographic image forming apparatus, is formed of an object to be charged, and a roller-shaped charging member disposed in contact with the object via electroconductive particles and supplied with a voltage to charge the objects. The charging member has a surface layer including an elastic foam and is moved with a surface speed difference relative to the object. The charging member has surface cavities having an average diameter of 5 to 150 mum and occupying an area percentage of 50 to 90%. An image forming apparatus and a process cartridge therefor including the charging device are also provided.