Processes for producing negatively charged toner

Abstract

A process for the preparation of negatively charged toner comprising: (i) preparing a pigment dispersion, which dispersion is comprised of a pigment, an ionic surfactant, and optionally a charge control agent; (ii) shearing said pigment dispersion with a latex or emulsion blend comprised of a resin of styrene-vinylidene chloride-acrylic acid, styrene-vinyl chloride-acrylic acid, styrene-chloroprene-acrylic acid, styrene-butylacrylate-vinylidene chloride-acrylic acid, styrene-butylacrylate-vinyl chloride-acrylic acid, styrene-butadiene-vinylidene chloride-acrylic acid, or styrene-isoprene-vinylidene chloride-acrylic acid, a counterionic surfactant with a charge polarity of opposite sign to that of said ionic surfactant and a nonionic surfactant; (iii) heating the above sheared blend below about the glass transition temperature (Tg) of the resin to form electrostatically bound toner size aggregates with a narrow particle size distribution; and (iv) heating said bound aggregates above about the Tg of the resin.

Dependencies are inferred from the claim text.