| 摘要 |
PROBLEM TO BE SOLVED: To obtain a small-sized ecological electrophotographic both-side printer by constituting the printer so that a bias roller may be brought into contact with a photoreceptor drum and also a bias whose polarity is opposite to the electrostatically charged polarity of unfixed toner on the 1st side of a paper may be applied within a specified value. SOLUTION: The bias roller 95 facing the photoreceptor drum 91 as a 2nd image forming means across a paper P7 carrying path is brought into contact with the photoreceptor drum 91, and also, the bias of 1000 to 6000 V whose polarity is opposite to the electrostatically charged polarity of the unfixed toner on the 1st side of the paper P7 is applied by such the constitution, in the case the applied voltage of the bias roller 95 is controlled within the extent of 1000 to 6000 V, the electrostatically charged polarity of the unfixed toner on the 1st side of the paper is converted without the sticking of the toner on the 1st side to the bias roller 95, irrespective of the kind of rollers, and also, without the occurrence of irregularities in the image on the 1st side of the paper, and the toner image is transferred from the photoreceptor drum 91 to the 2nd side of the paper. |
