| 摘要 |
PROBLEM TO BE SOLVED: To provide an excellent carrier for electrophotography which is excellent in durability, forms a fine image having no edge effect for a long period of time, and does not cause color contamination, and to provide a developer using the carrier. SOLUTION: The carrier has a coating layer, which includes a binding resin and conductive microparticles, on a carrier core material. In addition, at least the form coefficients SF-1 of the conductive microparticles are 160 or larger, and the ratio (Df/h) of the volume average particle size Df of the conductive microparticles to the thickness h of the coating layer satisfies an inequality 0.5<[Df/h]<1.5, and the coating rate (%) of the conductive microparticles to the core material, which is represented by an equation (1) ((Ds×ρs×W)/(4×Df×ρf))×100, is 70% or larger, wherein Ds represents the volume average particle size of the carrier core material, ρs represents the true specific gravity of the carrier core material, W represents the ratio of the amount of the added conductive microparticles to the carrier core material, Df represents the volume average particle size of the conductive microparticles, and ρf represents the true specific gravity of the conductive microparticles. COPYRIGHT: (C)2009,JPO&INPIT
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