JPS6466675A - Conductive roll - Google Patents

Abstract

PURPOSE:To prevent the formation of holes on the surface of a photosensitive drum and the generation of the contamination of said surface and to prevent the unequal colors of images by coating the surface of a conductive elastic material layer which is concentrically formed on the outside circumference of a shaft with a resin dielectric layer in which conductive particles having 10<1>-10<5>OMEGA.cm electric resistance are distributed. CONSTITUTION:The conductive elastic material layer 12 formed by dispersing the conductive powder such as carbon black or metal powder into rubber matrix is formed concentrically on the outside peripheral face of the shaft 10. The resin dielectric layer 13 in which the conductive particles of 10<1>-10<5>OMEGA.cm are dispersed is formed on the surface thereof. The resin dielectric layer 13 is hardly compressibly deformed and only the conductive elastic material layer 12 is compressibly deformed when this conductive roll is brought into pressurized contact with the surface of the photosensitive drum. The conductive roll is thus brought into face to face contact with the surface of the photosensitive drum at a specified contact width. The change is the spacings between the conductive particles distributed in the layer and the consequent change in the electric resistance value are, therefore, obviated. As a result, the generation of unevequally varied densities of colors in the copied images and the generation of the spark discharge on the surface of the phtosensitive drum are obviated.