| 摘要 |
<p>PROBLEM TO BE SOLVED: To stabilize transfer property at a secondary transfer position. SOLUTION: In this intermediate transfer unit, a toner image formed on a photoreceptor 110 is primarily transferred to an intermediate transfer belt 360, and the toner image is secondarily transferred to a recording medium by supplying bias from a high voltage power source to a secondary transfer member 380 made to press-contact with a backup roller 350. The resistance value of the secondary transfer member is 10<6> to 10<8>Ω, the surface resistance value of the intermediate transfer belt is 10<8> to 10<12>Ω/square, and volume resistivity is 10<8> to 10<12>Ωcm. The high-voltage power source performs constant-current control when the impedance of the secondary transfer part is large and performs constant-voltage control when the impedance is small.</p> |
