| 摘要 |
PURPOSE:To provide a two-component eletrostatic developer, and an electrostatic development method ensuring high imaging performance in image density, fog, image quality, cleanability, continuous stability or the like. CONSTITUTION:A developer and development method comprise a toner, and a carrier having a grain size within the range of 20 to 105mum. The quality of toner is specified at 5 to 8mum, 4 to 7mum and 50 to 95%, respectively in volumetric mean grain size range, mean grain size range per number and number ratio within a grain size between 4 and 8mum. An additive is contained in the toner by an amount of 0.3 to 5.0wt.% per toner unit weight. The additive is so prepared as to have a smaller grain size than the volumetric mean grain size of the toner. |
