DEVELOPING ROLLER, DEVELOPING DEVICE, PROCESS CARTRIDGE AND IMAGE FORMING APPARATUS

PROBLEM TO BE SOLVED: To provide an inexpensive developing roller capable of suppressing a reduction in the conveying amount of developer due to change with lapse of time and preventing image density unevenness caused by the vibration during the rotation of a developing sleeve, and to provide a developing device having the developing roller, a process cartridge having the developing device and an image forming apparatus having the developing device.SOLUTION: A developing roller 115 is configured so that a developing roller 132 is formed in a cylindrical shape, a cylindrical axis center P and a rotation axis Q of the developing sleeve 132 are not matched, and a large number of recesses 139 in a circular or elliptical shape in plan view are regularly arranged to be spaced apart from one another so as not to overlap one another on the outer surface of the developing sleeve 132. And, for the large number of recesses 139, the depth H of the recess 139 provided at a portion close to the rotation axis Q on the outer surface of the developing sleeve 132 is arranged to be deeper than the depth H of the recess 139 provided at a portion far from the rotation axis Q on the outer surface.