Patent ID: 7745087

Claim:
An electrostatic image developer comprising: a toner; and a carrier having a resin coating layer formed on the surface of a core material containing a ferrite component, wherein the developer has a ratio R 1 /R 2 of from about 0.88 to about 0.92 where: R 1 is the resistance value (Ω) of the developer having a toner concentration of 2 mass % when the developer is a magnetic brush, at an applied voltage of 10 4 V/cm; and R 2 is the resistance value (Ω) of a magnetic brush developer having a toner concentration of 12 mass % when the developer is a magnetic brush, at an applied voltage of 10 4 V/cm, the exposure ratio of the core material in the carrier is from about 2% to about 14% and the BET specific surface area of the core material in the carrier is from about 0.14 m 2 /g to about 0.28 m 2 /g.