Patent ID: 6190820
Filing Date: 2001-02-20
Classification: G03G

Abstract:
A process for the preparation of toner comprising(i) generating by emulsion polymerization in the presence of an initiator a first resin latex emulsion;(ii) generating by solution polymerization in the presence of an oil soluble initiator a second resin latex;(iii) mixing (ii) with a colorant thereby providing a colorant dispersion;(iiib) mixing the resin latex emulsion of (i) with the resin/colorant mixture of (iii) to provide a blend of resin and colorant;(iv) adding an inorganic cationic coagulant solution of a metal salt, an organic cationic coagulant solution or mixtures thereof to the resin/colorant blend of (iiib);(v) heating at a temperature of from about 5.degree. C. to about 10.degree. C. below the latex resin Tg of (i) to form aggregate particles, and which particles are at a pH of from about 2 to about 4;(vi) adjusting the pH of (v) to about 6.5 to about 9 by the addition of a base;(vii) heating the aggregate particles at a temperature of from about 5.degree. C. to about 50.degree. C. above the Tg of the latex resin of (i), followed by a reduction of the pH to from about 2.5 to about 5 by the addition of an acid thereby resulting in coalesced toner; and(viii) optionally isolating the toner.