| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an image forming device capable of obtaining a sufficient image density in a recessed portion on a recording paper surface. <P>SOLUTION: In a secondary transfer bias power source 39 outputting a superposition bias superposed with an offset voltage Voff to an AC component having a peak-to-peak voltage Vpp as a secondary transfer bias, a bias having the relation of 1/6×Vpp>¾Voff¾ is output as the second transfer bias. As is clarified from the experiments carried out by the present inventors, even when using recording paper having widespread surface ruggedness such as Japanese paper, a sufficient image density can be obtained in a recessed portion on a recording paper surface by outputting such a secondary transfer bias. <P>COPYRIGHT: (C)2012,JPO&INPIT |
