Abstract: A part for an ion implantation device employing a silicon carbide sintered body is provided. The density of the silicon carbide sintered body is 2.9 g/cm.sup.3 or more. The silicon carbide sintered body is obtained by sintering a mixture in which silicon carbide powder and a non-metal-based sintering additive are mixed uniformly. The non-metal-based sintering additive is formed of an organic compound which generates carbon upon heating or the like. As a result, a part for an ion implantation device with excellent heat resistance and ion resistance and which causes little contamination is provided.

Abstract: A charging device for electrically charging a photoconductor drum includes a charging member adapted to be placed in contact with the drum and an element for applying voltage between the charging member and the drum. The charging member has a microhardness of 1-65 degrees at its surface in contact with the drum or at least a surface layer of the charging member in contact with the drum is formed of a polyurethane which is prepared from liquid MDI as an isocyanate component and a polyol.

Abstract: A developing roller includes a metal shaft and a conductive resilient sleeve surrounding the shaft and made of a urethane elastomer containing carbon black with at least pH 5. The developing roller is mounted in an electrophotographic apparatus in combination with a latent image-bearing photoreceptor wherein development is carried out using a non-magnetic single-component toner.