| 摘要 |
PROBLEM TO BE SOLVED: To miniaturize a device and to save space without a restriction caused by image quality by regulating the shape coefficient of a toner particle in developer to be used within a specified range even in the case of using a developing sleeve whose curvature is large. SOLUTION: A small-diameter sleeve whose curvature 1/Rs (Rs is the diameter of the developing sleeve) is >=0.044 is used as the developing sleeve 2. Preferably, it is >=0.047 and more preferably >=0.05. As for the state of globurizing of the particle shape of the toner particle; it is a necessary condition that Wardell globurizing degree is 0.25 to 0.4. An electrostatic latent image is formed on a photoreceptor drum 1 and the developer 3 held by the sleeve 2 is allowed to pass through a developer regulating member 5, so that the developer 3 is supplied to the electrostatic latent image on the drum 1 by a fixed amount to develop the latent image. In repetitive use, toner 4 is made to fall through a toner replenishing roller 7 so as to replenish the developer 3 with the toner 4. In such a case, the toner 4 is mixed in the developer 3 by a developer stirring member 6. |
