To provide a roller high in durability and capable of preventing a photoreceptor and a roller from wearing, preventing toner from deteriorating, moreover, suppressing variations of a roller resistance value and maintaining a high quality image for a long period by properly adjusting a relation between the contact pressure and the contact width.
In the case of a roller provided with a single or plural resin layers 4 around a conductive shaft 3 and further concentrically provided with a surface layer 5 on this resin layer, the roller 2 for an electro-photographic system comprises such a conductive elastic layer for the constitution that when a linear load of a cylindrical electrode 1 of the same shape as a photoreceptor and the surface of the roller 2 is 2.2 g wt./mm, a circumferential contact width d of the cylindrical electrode 1 with the roller 2 is 1.0 mm or longer.
KOBAYASHI KENJI
MIMURA KAZUYOSHI
OGOSHI HIROSHI
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