Patent ID: 8551680

Claim:
A process for preparing a toner comprising the steps of: (a) preparing toner particles each of which contains at least a binder resin, a colorant, and a wax, and has a coat layer on the surface thereof; and (b) adding an inorganic fine powder to the toner particles, wherein the step (a) comprises: (i) providing a resin microparticle; (ii) providing an aqueous medium containing a color particle and a sparingly water-soluble inorganic salt, wherein the color particle contains at least the binder resin, the colorant, and the wax; (iii) forming a dispersion solution mixture by adding the resin microparticle to the aqueous medium; and (iv) immobilizing the resin microparticle to the color particle by: heating the dispersion solution mixture to a temperature of not less than T 2 (° C.) and not more than T s (° C.), where T 2 (° C.) is the glass transition point of the color particle and T s (° C.) is the glass transition point of the resin microparticle; adjusting a pH of the dispersion solution mixture to 5.0 or less to dissolve the sparingly water-soluble inorganic salt; and then heating the dispersion solution mixture to a temperature of not less than T 2 (° C.) and not more than Ts−30 (° C.) to Ts (° C.) or less, wherein the resin microparticle has a volume average particle size of 20.0 to 100.0 nm, wherein the resin microparticle has a zeta potential (Z 1s ) of from −110.0 mV to −35.0 mV, and wherein the color particle has a zeta potential (Z 2c ) of −15.0 mV or less, the zeta potential (Z 2c ) satisfying the relationship: (Z 1s +5.0) to (Z 1s +50.0) mV.