| 摘要 |
PROBLEM TO BE SOLVED: To suppress a decrease in image quality caused by a developer holding member having concave grooves formed at distances in a circumferential direction on an outer peripheral surface of a cylindrical body.SOLUTION: A developing sleeve 106B (sleeve body 200) is produced in an ellipsoidal shape to make concave grooves 110 on a long axis L1 side of an ellipse shallow, and concave grooves 110 on a short axis L2 side deep. On the long axis L1 side of the ellipse in the developing sleeve 106B, a developing gap becomes narrow but the amount of developer (conveyance amount) is reduced; in contrast, on the short axis L2 side, the developing gap becomes wide but the amount of developer G (conveyance amount) increases. Accordingly, unevenness in the amount of developer supplied to a photoreceptor 72 is offset, and unevenness in image density is suppressed. |
