ROLLER MEMBER FOR ELECTROPHOTOGRAPHY, PROCESS CARTRIDGE AND ELECTROPHOTOGRAPHIC APPARATUS

摘要

PROBLEM TO BE SOLVED: To provide a roller member which suppresses uneven wear of a photoreceptor and generation of a banding image even in long-term use.SOLUTION: A roller member for electrophotography includes a conductive substrate and a conductive elastic layer as a surface layer. The conductive elastic layer has a crown shape in which an outer diameter at the middle in a longitudinal direction of the roller member is larger than outer diameters at both ends of the roller member. The conductive elastic layer contains a binder and bowl-shaped resin particles; and the surface of the roller member includes recesses derived from openings of the bowl-shaped resin particles and projections derived from edges of the openings. The relationship in a restoring rate for elastic deformation between at the middle in the longitudinal direction of the roller member and at both ends of the member is such that: on the surface of the conductive elastic layer, the restoring rate is larger at both ends than that at the middle; and at the position of depth t μm from the elastic layer surface, the restoring rate is larger at the middle than that at both ends.