The present invention provides a conductive roller having a core and a
conductive foam formed on a peripheral surface thereof.
The conductive foam consists of a three-phase rubber composition
containing 35 to 50 parts by mass of epichlorohydrin rubber, 25 to 35
parts by mass of ethylene-propylene-diene copolymer rubber, and 25 to 30
parts by mass of acrylonitrile-butadiene rubber as a rubber component
thereof. The conductive foam does not have a coating layer formed on a
surface thereof.
The conductive roller has an Asker C hardness, an electric resistance
value, an average surface-cell diameter, and a number of surface cells
set to 30 to 36.degree., 10.sup.6 to 10.sup.7 .OMEGA., 100 to 200 .mu.m,
and 50 to 120/1.5 mm square respectively.