DEVELOPING ROLLER, DEVELOPING DEVICE AND IMAGE FORMING DEVICE

摘要

PROBLEM TO BE SOLVED: To provide an inexpensive developing roller having high magnetic characteristics and high precision in the main polar part. SOLUTION: The peak width of a developing polar part of a ferrite magnet roller 51 is made smaller than that of a rare earth element magnet block 54. As a result, the half-value width of the magnetic waveform (a solid line shown in the figure) of the developing polar part as a magnet roller body 50 can be made to be 20 deg. or smaller and the magnetic flux density can be attained to 80 mT.