Patent ID: 8148041

Claim:
A method of preparing a carrier comprising a core particle made of ferrite comprising Mg and coated thereon, a resin, comprising the steps of: (1) preparing a raw material to produce the ferrite containing Mg by mixing compounds; (2) wet mixing by adding water into the mixture obtained in step (1), dispersing the resulting to prepare slurry, and also adjusting concentration of the slurry, to at least 70% by weight; (3) wet pulverizing the slurry to obtain a pulverized material; (4) granulating and drying the pulverized material to obtain a ferrite granulated material; (5) baking the ferrite granulated material at a baking temperature of at least 1500° C.; (6) pulverizing the baked ferrite granulated material; (7) classifying the pulverized baked material to obtain the core particle; and (8) coating the core particle with the resin, wherein the core particle has a ratio of the number of irregular-shaped core particles of at most 5%, based on the total number of core particles, and a surface of the core particle has grains having a maximum grain diameter of 2-5 μM.