| 摘要 |
PURPOSE:To form a toner image directly on a transfer member by generating ions which differ in polarity from electrostatically charged toner at the opposite side of the charged toner layer across a transfer member, and sticking the toner with Coulomb force operating between the ions and charged toner. CONSTITUTION:High-resistance single-component toner 1 having magnetism is held on a sleeve 32 by the magnetic pole group 31 in a developing roller 3 and layered to constant layer thickness by a doctor blade 21 through the rotation of the roller 31 shown by an arrow 7. Further, the toner is charged electrostatically to the positive polarity by the friction against the sleeve 32 or blade 21. At the same time, a negative ion flow generated between the corona wire 61 and casing 62 of an ion flow control head of arranged under a transfer member 5 is controlled with an electric field established between a control electrode 63 connected to a bias power source 69 and each recording electrode 63 connected to a recording power source switched on the basis of image infor mation to be recorded, thereby forming a toner image on the transfer member 5. |
