Abstract: The invention provides a process cartridge and a high performance image forming apparatus in which no image defect such as image deletion, is caused by appropriately reducing the dispersion of a surface property between plural photoconductors used in the color image forming apparatus of a tandem system particularly at the early stage. Therefore, the process cartridge for the image forming apparatus of the tandem system has a photoconductor having at least a photosensitive layer on an electrically conductive substrate, and also has image forming apparatus for forming a toner image on the surface of the photoconductor. The electrically conductive substrate has a sandblast-processed outer surface. The image forming apparatus of the tandem system has plural photoconductors each having at least a photosensitive layer on an electrically conductive substrate, and also has apparatus for respectively forming toner images of plural colors on the surfaces of the photoconductors.

Abstract: An electrophotographic photoreceptor for incorporation in a process cartridge and removably mounted in the main body of an electrophotographic device. The photoreceptor includes a photosensitive drum having a cylindrical conductive substrate and a photosensitive layer formed on the substrate's outer peripheral surface. The photoreceptor has a gear flange engaged with an open end of the drum, for transmitting rotational driving force from the main body to the drum. A driving force transmitting section, designed to achieve rotational accuracy and rotational strength and realize reduced production costs, includes at least two projected portions inclined in a direction substantially opposite to the rotational direction of the drum, and arranged concentrically about the central axis of the drum. The driving force transmitting section also includes a raised portion, formed on a rotational driving force receiving surface of the gear flange, which reinforces an area between the projected portions.