| 摘要 |
PURPOSE:To enhance image density and to prevent fogging by controlling the concentration of a photosensitive toner in a binary developer to a concentration satisfying a specified condition. CONSTITUTION:An image is formed by applying voltage, exposing at the same time, developing with a combination of the photosensitive toner and a magnetic carrier, and transferring the toner image, and the concentration of the toner is lowered as compared with the concentration of the toner in the conventional binary developer, and its concentration is controlled in relation to the specific areas of the carrier and the toner into the range represented by the equation (1), where Sc is the specific surface (cm<3>/g) of the magnetic carrier, and St is that of the toner, and (k) is 0.0-2.0, thus permitting image density to be enhanced while remarkably restraining fog density. |
