Patent ID: 6077637
Filing Date: 2000-06-20
Classification: G03G

Abstract:
An image formation method comprising the steps of (a) uniformly charging the surface of a photoconductor to a predetermined polarity, (b) forming latent electrostatic images comprising low potential portions and high potential portions on said photoconductor by subjecting the charged surface of the photoconductor to selective light radiation, thereby selectively reducing the potential of the surface of said photoconductor, and (c) developing said latent electrostatic images to visible toner images by bringing a developer into contact with the latent-electrostatic-images-bearing photoconductor, thereby causing the toner contained in the developer to be selectively deposited on the latent-electrostatic-images-bearing photoconductor, wherein as said developer, there is employed a developer comprising (i) a carrier which comprises magnetic carrier particles having an average particle size between 20 and 50 .mu.m and having at least one of a maximum magnetization of between 50 and 200 emu/g in a magnetic field of 5 KOe, and a maximum magnetization of between 40 and 90 emu/g in a magnetic field of 1 KOe, wherein the magnetic carrier particles having a particle size of 35 .mu.m or less constitute 15 to 90 wt. % of the magnetic carrier, and the magnetic carrier particles having a particle size of 20 .mu.m or less constitute 15 to 30 wt. % of the magnetic carrier, and (ii) toner particles.