| 摘要 |
PURPOSE:To obtain a carrier capable of forming a developer ensuring high image quality and long service life by mixing with a toner by specifying the ratio between dynamic resistance at the time of impressing specified DC voltage. CONSTITUTION:This carrier is a coated carrier for a two-component developer for development with a magnetic brush, is obtd. by coating the surfaces of core particles of a magnetic body with a resin and has 1.8-5.0 ratio (R100/R300) of dynamic resistance at the time of impressing 100V DC voltage to that at the time of impressing 300V DC voltage. The magnetic body is, e.g. magnetite or ferrite represented by a general formula MO.nFe2O3 (where M is Fe, Cu, Mg, Ni, Co, Mn, Cd, etc.). The resin is, e.g. silicone resin or modified silicon resin. Since dynamic resistance dependent on voltage is rendered to the coated carrier, an electrostatic latent image on a photosensitive body can be reproduced with high image quality from a part with low surface potential to a part with high surface potential, that is, from halftone to a line image area or a solid black area without causing unnecessary wear to the photosensitive body. |
