Patent ID: 8475992

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: providing an aqueous dispersion of neutralised self-dispersed polyester resin particles and colorant particles stabilised by an ionic surfactant, wherein the acid groups on the polyester resin and the ionic surfactant in the dispersion are reversibly ionisable or de-ionisable; associating the polyester resin particles and colorant particles by means of a change in the pH of the dispersion which causes the neutralised acid groups of the polyester and ionic surfactant to convert from an ionic to a non-ionic state; and a further step of heating, stirring or heating and stirring the associated particles at a temperature from 5 to 25° C. below the glass transition temperature of the binder.