| 摘要 |
PURPOSE:To obtain always a sharp two-color picture by providing a separator for a toner, by the 1st development to the 2nd developing device, thereby preventing the accumulation of the toners by the 1st development in the 2nd developing device in long-term recording. CONSTITUTION:A toner wherein a polarity inverted red toner and a black toner 19 are coupled, rotate at a high speed on a separating roll 2 and are dropped into a toner well 22 from carriers 18 by centrifugal forces. If the roll 21 is rotated during development, the red toner 17 mixed with said toners is easily separated. The iron powder coated with resins such as polyfluorocarbon, PVC or the like is used for the carriers and resins such as styrenic, acrylic, epoxy or the like which are added with carbon, etc. and are further added with control materials for quantity of electrostatic charge are used for the toner. |
