| 摘要 |
PROBLEM TO BE SOLVED: To make an excellent image formed where problems such as the developer deterioration, the scratch mark generation on a developing sleeve, an insufficient charge of the developer, deterioration of the image density or the like are eliminated as well as suppression of ghost occurrence to leave the image history on a developing sleeve. SOLUTION: This developing device is allowed to form the developer peeling magnetic fields by arranging 2 magnetic poles in the same polarity adjacent to each other among plural magnetic poles in the magnet roll 42 (N2 and N3), allowed to arrange a magnetic body 48 opposite to the developing sleeve 41 in a state of non-contact without inserting any other member therein in a range of angle formed by the normal line that connects the magnetic pole N2 in the direction opposite to that of the gravity between 2 poles in the same polarity and the center of the developing sleeve and the normal line that connects the neutral pole part Nu between 2 magnetic poles in same polarity and the center of the developing sleeve 41, and allowed to arrange the polarity on the side opposite to the developing sleeve 41 of the magnetic body in the polarity S being different from the two magnetic poles N2 and N3 in the same polarity. |
