| 摘要 |
<P>PROBLEM TO BE SOLVED: To restrain, even where a developing device that places toner in a flare state on an insulative external circumferential face of a toner carrier, variations in picture over time due to variations of a developing electric field over time. <P>SOLUTION: In a developing device in which toner is carried on an insulative external circumferential face of a toner carrying roller having an inside electrode and an outside electrode and an electric field for hopping the toner (flare electric field) in external circumferential face parts opposite the inside electrode and the outside electrode by applying mutually different voltages to the inside electrode and the outside electrode, such a voltage as makes the potential difference between the surface of a toner feed roller that feeds the toner to the external circumferential face of the toner carrying roller equal to or higher than a discharge start voltage is applied to the toner feed roller. <P>COPYRIGHT: (C)2012,JPO&INPIT |
