| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a full color image forming device capable of forming a full color image of good quality and also forming a stable monochromatic image. SOLUTION: A 4th developing device 1 is provided with a developer container 2 for storing two-component developer, a developer carrier 10 with a built-in magnetic field generating means 11 and a developer control means 30 arranged adjacent to the developer carrier 10. The magnetic field generating means 11 is provided with a 1st magnetic pole in the developer container 2 so as to be positioned on the downstream side of the developing part in the developer carrier 10 rotating direction and a 2nd magnetic pole adjacently positioned on the downstream side of the 1st magnetic pole in the developer carrier rotating direction and whose polarity is the same as that of the 1st magnetic pole, and a repulsive interpole area is formed between the 1st and 2nd magnetic poles. The developer control means 30 is arranged near the opposed position of the 2nd magnetic pole, and the 4th developing device 1 is positioned so that an angleθ1 formed by a line linking between the rotational center axis of the image carrier 100 and the rotational center axis of the developer carrier 10 and a vertical line passing through the rotational center axis of the image carrier 100 may be 0±5 deg., and as for magnetic carrier contained in the two-component developer, the residual magnetic is 2 to 10 emu/g and the average particle size of the magnetic carrier is 20 to 100μm.</p> |
