Domains of a charge control resin are formed by dispersing a charge control resin containing a quaternary ammonium salt functional group-containing resin of a copolymer of an addition-polymerizable monomer having a quaternary ammonium salt functional group and a styrene and/or acrylic monomer into a polyester resin as binder resin, and the proportion of the number of domains of the charge control resin with a domain diameter of no less than 0.01 [mu]m to less than 0.3 [mu]m versus the number of domains of the charge control resin with a domain diameter of no less than 0.01 [mu]m, which is measured by a predetermined method, is no less than 98% by number.