| 摘要 |
PURPOSE:To perform excellent, high-speed development without scattering toner and carrier by using a magnetic developer with specific composition and a developing means suitable to the developer in combination. CONSTITUTION:The developer 22 consists of toner which incorporates magnetic powder and ferromagnetic carrier such as ferrite carrier and iron powder carrier which have >=45emu/g maximum magnetization characteristics in a 1,000Oe magnetic field and a >=20mum mean particle size, and the mixing ratio of the toner and carrier is so determined that carrier surfaces are covered with the toner by 100%. This developer is held around a sleeve 3 wherein a magnet roller 21 rotates to a >=1mm. thickness. The magnetic toner is used, so toner scattered by inner center force is attracted onto the sleeve 3 again by magnetic force. |
