| 摘要 |
PROBLEM TO BE SOLVED: To provide a two-component developer capable of stably supplying a high-quality image without a fog, a leakage mark, the sticking of a carrier and an edge effect, over a long period by using a core incorporating a magnetic substance, which shows an impedance of a specific value or more, at a specific sinusoidal AC voltage, as a core material for a coating carrier. SOLUTION: As the core material for the coating carrier, the core containing the magnetic substance, which shows an impedance of >=1×10<8> Ω.m, at a sinusoidal AC voltage whose amplitude is 2kV and frequency is 2kHz is used, so that the high-quality image is obtained. Further, a capacitor layer which is formed on the surface of the core material for the carrier and has a capacitance component is provided and capacitance obtained from the applied voltage frequency dependency of the impedance measured at the sinusoidal AC voltage whose amplitude is 2kV, of the carrier is at a value of 1×10<-15> F-1×10<-11> F. Thus, the problems of reduction in the edge effect and the density of an image, etc., occurring when a material whose electric resistance is high is used as the carrier for a developer are eliminated. |
