Patent ID: 8377621

Claim:
A process for preparing a toner comprising a binder resin and a colorant, wherein the binder resin comprises a polyester resin having an acid value greater than 5 mg KOH/g, the process comprising: i) providing an aqueous dispersion of polyester resin particles stabilised by an ionic surfactant which is reversibly ionisable or de-ionisable; and ii) then associating the polyester resin particles by a change in the pH of the dispersion which causes the ionic surfactant to convert from an ionic to a non-ionic state; and then iii) heating and/or stirring the associated particles at a temperature of from 5 to 25° C. below the Tg of the binder resin; and then iv) raising the temperature to 20 to 35° C. above the Tg of the binder resin in a fusion step.