Abstract: An electrically biased magnetic brush is used to remove background toner particles from a photoreceptor, and an electrically biased reclaim roller is used to remove the toner particles from the magnetic brush. Before contacting the photoreceptor once again, the bristles of the magnetic brush are discharged by a charge bar, the bristles having been charged by the biased reclaim roll. A second reclaim roller biased to the opposite polarity of the first may also be used to remove toner particles from the magnetic brush to be certain that toner particles of opposite polarities are removed from the magnetic brush. In addition, if desired, a mixture of two groups of carrier beads may be used to form the bristles of the magnetic brush, the groups having different tribo-electric properties.

Abstract: Latent electrostatic images carried by a photoconductively coated substrate of an electrostatic processor are developed in a magnetic field free development zone by a multicomponent developer. The developer circulates in a path which runs from a lower level of a sump, upwardly through the development zone, and then back to the sump. To that end, there are means below the development zone for propelling the developer upwardly into and through that zone, together with means above the development zone for capturing the excess developer (i.e., the developer not consumed in the development process) emerging from that zone. In one embodiment, there are separate magnetic transport rolls for propelling the developer into the development zone and for recapturing the excess developer. To accomodate that embodiment, a developer containing ferromagnetic carrier particles and toner particles is used.