Semiconductive roller, method for manufacturing the same and image forming apparatus

A semiconductive roller comprising:

• a conductive support;
• and
• a semiconductive elastic layer disposed on a circumferential surface of the conductive support, the semiconductive elastic layer containing at least an epichlorohydrin rubber, an acrylonitrile-butadiene rubber, and a conducting agent and having a foam structure, wherein a mixing ratio of the epichlorohydrin rubber to the acrylonitrile-butadiene rubber ranges from 80/20 to 20/80 by mass,
• wherein, when the semiconductive roller is immersed in pure water for 30 minutes, a chlorine ion content derived from the semiconductive elastic layer per unit area of the semiconductive elastic layer is approximately not more than 0.06 μmol/cm2,
• wherein no electricity has been run through the semiconductive roller before the semiconductive roller is immersed in the pure water for 30 minutes, and
• wherein a volume resistivity of the semiconductive roller ranges from greater than 7 logΩ·cm to 13 logΩ·cm at 20° C.,
• the semiconductive roller being manufactured by a process comprising a cleaning process that comprises immersing the semiconductive elastic layer into pure water for approximately not less than 30 minutes for cleaning.