| 摘要 |
PURPOSE:To quantitatively evaluate the characteristic of toner based on an actual copying machine by measuring the developing current generated for toner sticking to a drum and the surface potential of toner at this time with a constitution adapted to the actual development process. CONSTITUTION:Toner is supplied into a hopper 8 and is moved on a sleeve 3 by rotation of the sleeve 3 and is carried to a development area and is stuck to the drum there to develop an image. The developing current to be monitored is measured continuously or intermittently until most of toner in the hopper is consumed after fresh toner is set to the hopper to start development. The transition of the current is traced to evaluate the long-time stability of toner, and simultaneously, the surface potential of the toner layer which passes the development area is monitored also. Thus, the initial characteristic and the life characteristic of toner are quantitatively evaluated. |
