| 摘要 |
PROBLEM TO BE SOLVED: To reduce the driving torque of a supplying roller. SOLUTION: This developing unit is constituted to use toner having a shape factor SF-1 for showing the round degree of the toner of <=150 and a shape factor SF-2 for showing the rugged degree of the toner of <=140 and provide a developing roller 211 and the supplying roller 240 of a foamed body coming into press-contact with the developing roller 211, to supply the toner to the surface of the developing roller 211. At this time, the consecutive foam rate of the supplying roller 240 is >=30% and the biting depth of the supplying roller 240 on the developing roller 211 is <=0.4mm. |
