Patent ID: 8642236
Filing Date: 2014-02-04
Classification: G03G

Abstract:
1. A tandem-system color image forming device including a drum type electrophotographic photoconductor, a rotation speed of which is 70 rpm or more, wherein the color image forming device is provided with a positive charging type electrophotographic photoconductor by which an image density is maintained at a value of 1.3 or more, wherein the electrophotographic photoconductor comprises a photosensitive layer containing a mixture of at least a charge-generating agent, a hole transfer agent, an electron transfer agent, and a binder resin carried on a conductive substrate, the conductive substrate comprising an aluminum base tube, the charge-generating agent comprising an X-type non-metal phthalocyanine, the binder resin comprising a polycarbonate resin represented by the formula (1) having a viscosity average molecular weight of from 20,000 to 80,000, the hole transfer agent comprising a compound represented by formula (2) or (5), the electron transfer agent is comprising a compound represented by the formula (9), and wherein, when Vb (V) denotes a sensitivity in the case where an amount of light exposure per unit area is 0.6 μJ/cm wherein the sensitivity (Vb), in the case where the amount of light exposure per unit area is 0.6 μJ/cm wherein the sensitivity (Va), in the case where the amount of light exposure per unit area is 1.5 μJ/cm