Abstract: An electroconductive roller is capable of exhibiting stable conductivity regardless of environmental change and is accompanied by small bleed-out of additives. The conductive roller includes an electroconductive support, an electroconductive elastic layer coating the support and a resistance layer coating the elastic layer; wherein the elastic layer comprises at least one species of rubber selected from the group consisting of acrylonitrile-butadiene rubber, epichlorohydrin rubber and chloroprene rubber, an ether oxygen containing alkyl phthalate derivative, a quaternary ammonium perchlorate compound and a fatty oil, and the ether oxygen-containing alkyl phthalate derivative, quaternary ammonium perchlorate compound and fatty oil are contained in a total amount of 0.1-20 wt. parts per 100 wt. parts of the rubber. The conductive roller is suitably used as a contact charging member in an electrophotographic apparatus.

Abstract: A charging member suitable for charging, e.g., a photosensitive member for electrophotography, is provided with improve surface-properties. The charging member is surface with a resin formed by plasticizing a rigid polymer with a plasticizing polymer chemically bonded to the rigid polymer.

Abstract: A charging member for charging a charge-receiving member, such as an electrophotographic photosensitive member, by disposing the charging member in contact with the charge-receiving member and applying a voltage to the charging member is constituted by disposing an electroconductive support, an elastic layer, and a surface coating layer having a tensile modulus of above 2000 kgf/cm.sup.2 to at most 30000 kgf/cm.sup.2 in this order. The coating layer may preferably contain an acrylic polymer-modified urethane resin. The charging member is effective in providing the charge-receiving member with a nip portion showing a uniform electric resistance distribution for a long period to provide excellent images.

Abstract: A charging member contactable to a member to be charged to electrically charge it, the improvement residing in that a microhardness of an end region, with respect to a longitudinal direction, of the charging member is larger than that in a central region of the charging member.

Abstract: A charger having a surface layer, the content of components of the surface layer having a molecular weight of 1,000 or less in a resin is 0.5 wt % or less, charges a member to be charged by contacting the member to be charged in an electrophotographic apparatus or the like.