Patent ID: 6352810
Filing Date: 2002-03-05
Classification: G03G

Abstract:
A process for the preparation of toner comprising(i) providing or generating a latex emulsion of resin, water, and an ionic surfactant, and providing or generating a colorant dispersion containing a colorant, water, an ionic surfactant, or a nonionic surfactant, and wherein (ii) the latex emulsion is blended with the colorant dispersion; (iii) adding to the resulting blend containing the latex and colorant a polyamine salt coagulant; (iv) heating the resulting mixture below about the glass transition temperature (Tg) of the latex resin; (v) optionally adding a second latex comprised of resin particles suspended in an aqueous phase; (vi) adding an oxidative or oxidizing agent or component to (v) followed by changing the pH with a base from an initial pH of about 1.9 to about 3 to a pH of about 5 to about 9; (vii) heating (vi) above about the Tg of the latex resin; (viii) optionally retaining the mixture (vii) at a temperature of from about 70Â° C. to about 95Â° C.; (ix) changing the pH of the mixture (viii) by the addition of an acid to arrive at a pH in the range of about 1.5 to about 3.5; (x) optionally washing the resulting toner slurry; and (xi) optionally isolating the toner.