LATER ELECTROGRAPHICAL IMAGE ON A SUPPORT LEAFLET, MAGNETICAL DEVELOPMENT APPROVED FOR USE IN APPLICATION, AN IMAGE OF THEM LATER AND A REVIEW OPPORT, AND APPEARANCE APPEARED TO REVIEW U

摘要

A magnetic brush for use in applying to a latent electrophotographic image on a carrier sheet a developer powder constituted by a mixture of particles of magnetizable material and a powdered toner and comprising a rotatable hollow cylinder of non-magnetic material and a stationary permanent magnet disposed within the cylinder, in which the cylinder also contains a screen of magnetizable material, the magnet and the screen being so disposed in relation to the cylinder as to produce at the surface thereof successive magnetic field zones of medium intensity sufficient to take up developer powder, of higher intensity for causing filaments to project radially from the cylinder for application of toner powder to the image and of intensity low enough to shed developer powder from the cylinder.