| 摘要 |
<p>PROBLEM TO BE SOLVED: To prevent the scattering of a toner, to make an image free from fog and unevenness in density and to form a stable satisfactory image over a long period of time by incorporating a positive charge type toner, two kinds of specified inorg. fine particles and a specified carrier. SOLUTION: This developer contains a positive charge type toner, 1st inorg. fine particles having 0.1-3μm number average particle diameter, 2nd inorg. fine particles having 0.005-0.02μm average primary particle diameter made hydrophobic by treatment and a carrier contg. magnetic powder dispersed in a resin binder and having 40-80μm vol. average particle diameter and 40-120nA dynamic electric current value. A developing sleeve 41 is disposed so that it confronts an amorphous silicon photosensitive drum P at the required interval Ds and a magnetic roll 42 having plural magnetic poles N, S,... is fixed in the sleeve 41. The developer (d) is housed in a device 40 and fed to the sleeve 41 after mixing and stirring by means of a mixing and stirring member 46.</p> |
