Abstract: A biphenyl derivative is included in a photosensitive layer of an electrophotographic photoconductor. The electrophotographic photoconductor includes a single-layer photosensitive layer coated on a conductive substrate. The photosensitive layer includes a resin binder, a charge generation substance, a hole transport substance, and an electron transport substance. An electrophotographic apparatus using such an electrophotographic photoconductor has excellent electrical characteristics in a positive chargine system and is stable in repeated use.

Abstract: A photosensitive material for use in electric photography, which comprises in sequence a conductive substrate; a carrier transport layer consisting of a selenium/arsenic alloy; a carrier generation layer consisting of a selenium/tellurium alloy; and an overcoat layer consisting of a selenium/arsenic alloy; wherein carrier injection preventive layers consisting of a selenium/arsenic/sulfur alloy are inserted between the conductive substrate and the carrier transport layer, and between the carrier generation layer and the overcoat layer, or between the carrier generation layer and the overcoat layer, or between both.

Abstract: An electrophotographic photoreceptor is provided comprising, in sequence:a) a conductive base;b) a carrier transport layer;c) a carrier generation layer comprising a selenium alloy;d) a carrier injection regulating layer having a band gap energy greater than that of the carrier generation layer and comprising selenium and up to about 10 weight % arsenic;e) a thermal expansion relieving layer comprising aresenic and selenium; andf) a surface protective layer comprising arsenic and selenium in an atomic ratio of approximately 2 to 3;wherein the arsenic concentration in the thermal expansion relieving layer gradually increases from a concentration substantially equal to that of the carrier injection regulating layer on a face of the thermal expansion relieving layer adjacent to the carrier injection regulating layer to a concentration substantially equal to that of the surface protective layer on an opposite face of the thermal expansion relieving layer adjacent to the surface protective layer.

Abstract: An improved electrophotographic photoreceptor of a function separation type for long wavelength light is provided which comprises an As.sub.2 Se.sub.3 carrier transport layer, a 30 to 50 wt % Te-Se alloy carrier generation layer and an As.sub.2 Se.sub.3 surface protective layer and an outer layer of a transparent insulating material.