IMAGE FORMING DEVICE, AND CONTROL METHOD THEREFOR

摘要

PROBLEM TO BE SOLVED: To perfectly eliminate electrical electrostatic offset and to perform excellent image recording over a long term by providing an electric field forming means forming electric field between a fixing member and a transfer materiel. SOLUTION: A corona electrifier 316 is provided to be opposed to an upper fixing device 310 and imparts positive charge whose polarity is the same as that of the toner charge of a toner image on the upper surface of recording paper P to the surface of an insulated roller. A corona electrifier 326 provided to be opposed to a lower fixing roller 320 imparts negative charge whose polarity is the same as that of the toner charge of the toner image on the lower surface of the recording paper P to the surface of the insulated roller. The electrifiers 316 and 326 are used as an electric field forming means, the roller 310 is electrified to have the same polarity as that of the toner charge of the upper toner image, and the roller 320 is electrified to have the same polarity as that of the toner charge of the lower toner image to enhance electric repulsive force between the toner and the roller, so that a double-sided toner image is fixed altogether.