CHARGING OF REPLENISHING TONER

This invention is generally directed to an improved process for rapidly charging uncharged replenishment toner particles to a positive polarity, and the use of such particles for developing images in an electrostatographic imaging system, which process comprises (1) adding uncharged replenishment toner particles to a charged developer composition comprised of carrier particles and toner particles, the carrier particles consisting of a core containing a polymer coating thereon having incorporated therein an additive having a pKa of less than 5, said additive being selected from the group consisting of perfluorooctanoic acid, 2,4-dinitrophenol, 2,4,6-trinitrophenol, and naphthalene sulfonic acids, (2) contacting the charged developing composition containing said carrier particles with the uncharged toner particles, wherein positive charges are transferred to the uncharged toner particles within a mixing period of from about 5 seconds to about 5 minutes, thereby resulting in substantially the same level of positive charge intensity for said uncharged toner particles as the charge intensity of toner particles in the charged developer composition, said charge intensity ranging from about 0.1 femtocoulombs per micron, to about 3 femtocoulombs per micron of toner particles.