| 摘要 |
PROBLEM TO BE SOLVED: To provide a developing device capable of improving toner conveyability, sticking resistance, and filming resistance of a developing roller.SOLUTION: A developing device comprises: a toner with the aggregation degree of 50 to 90%; and a developing roller that rotates while carrying the toner. The developing roller comprises, on the surface: a plurality of streak-like groove parts extending in a circumferential direction; and a plurality of step parts extending in a rotation shaft direction. |
