Charging device, process cartridge, image forming apparatus, and toner

摘要

The present invention provides a charging device which comprises a charging roller (14a) and a cleaning component (14b). The charging roller charges a surface of an image-recording medium (11) with a voltage which is applied from an external source. The cleaning component cleans a surface of the charging roller. The charging roller includes a resistance adjustment layer which is made of a resin composite and formed on an outer periphery of a core metal. The hardness of the charging roller is 45 degrees or more in JIS D hardness. The cleaning component has a portion which is in contact with the charging roller. This portion is made of resin foam which has a continuous foam structure. The density of the resin foam is 5 to 15 kg/m3 and its tensile strength is 1.7±0.5 kg/cm2.