| 摘要 |
PROBLEM TO BE SOLVED: To provide a developing device and an image forming device equipped therewith capable of reducing irregular density caused by history at the time of developing generated in the cycle of a developing roller and forming a neutral tint image with good reproducibility. SOLUTION: In this developing device, color toner which does not include carbon black is used. The device is constituted to satisfy a condition m2=am1 (0.75<=a<=0.95) assuming that the weight per unit area of the toner carried on a developing roller 25 just before the next developing after forming a white image on the entire surface of a photoreceptor drum 18 is m1, and the weight per unit area of the toner carried on the roller 25 just before the next developing after forming a color solid image on the entire surface of the drum 18 is m2. Thus, electrification amounts (Q/M) per unit weight for the former toner and the latter toner are made approximately equal and the irregular density caused by the history at the time of developing is reduced. |
