| 摘要 |
PURPOSE:To sharpen an electric charge distribution after replenishing a toner and to reduce attachment of the toner to the nonimage part of a photosensitive body by forming an external additive layer composed of fine particles of silica and metal oxide specified in electric resistance on the surface of each toner so as not to form a napping structure. CONSTITUTION:The external additive layer composed of the metal oxide fine particles 2 having a resistivity of 10<2>-10<9>OMEGA.cm and fine silica particles 3, or the fine particles 2 and 3 and cleaning aid particles 4 is formed on the surface of each toner particle 1. The additive layer is not allowed to form any napping structure. The additive particles attach to each other and to the toner particles 1 comparatively strongly in such a manner as coating the whole part or a part of the surface of each toner 1, thus permitting the obtained developer to be sharp in the charge distribution after mixing the additional toner and small in attachment of the toner to the nonimage parts of the photosensitive body. |
