Abstract: An organic photoreceptor for electrophotography including a substrate which is electrically conductive; and an organic photosensitive layer which is formed on the substrate, which includes a photoconductive material, and which has a surface having a differential hardness corresponding to a 20 .mu.m or less change in width of a scratch formed on the surface for every 10 g change in vertical load during perpendicular loading with 10 g or more pressure on the surface when a test for evaluating differential hardness is performed by moving the photoreceptor to a predetermined position at a constant speed of 30 mm/minute under a load in a direction perpendicular to the surface through a conical indenter to make the scratch on the surface, which conical indenter is one of a sapphire or diamond conical indenter having a conical tip portion including an apex having a hemisphereical shape with a diameter of 0.01 mm and a conical angle of 90.degree..

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 electrophotogrpahic printer having a photoconductor with an As.sub.2-x Se.sub.3+x (0<x<0.5) overcoat layer and a carrier generation layer comprising a Se-Te alloy containing about 42% by weight of tellurium is provided in which the charge-removing light has a wavelength shorter then 680 nm, and the time interval between the removal of charge and the re-electrification is in excess of 400 msec, thus minimizing the potential drop at the surface of the photoconductor.

Abstract: The present invention provides a seleniumn electrophotographic photoreceptor comprising a laminate of a conductive base, a carrier transportaion layer consisting of amorphous selenium or an amorphous Se-Te alloy, a carrier generation layer consisting of an amorphous Se-Te alloy containing 20 to 50 wt % of Te, and an overcoat layer composed of two layers consisting of Se-As alloys having different arsenic concentrations and different thickenesses. In one embodiment of the invention, the lower overcoat layer contains 2-10% by weight arsenic while the upper overcoat layer contains 10-30% by weight arsenic. In another embodiment of the invention, the thickness of the upper overcoat layer is greater than that of the lower overcoat layer but not more than 8 .mu.m.

Abstract: A photosensitive material for electrophotography is provided, which comprises in sequence an aluminum substrate, a charge transport layer, a hole injection layer, a charge generation layer, and a surface protection layer, wherein the surface protection layer comprises an arsenic-selenium alloy containing from 35 atomic % to 45 atomic % arsenic.The photosensitive material may also include a buffer layer comprising an arsenic-selenium alloy disposed between the surface protection layer and the charge generation layer, said buffer layer having a graduated arsenic concentration in which the concentration of arsenic increases in the direction of the surface protection layer. These layers provide enhanced lifetime for the materials while maintaning good print quality. Further, the insertion of the buffer layer allows for high temperature operation.

Abstract: The present invention provides a photosensitive body of Se-based function separation type to be used in electrophotographic equipment which employs long wavelength light for writing. Such a body exhibits outstanding abrasion resistance and heat resistance without sacrificing good electrical properties. This is accomplished by interposing an intermediate layer of As-Se alloy between the surface protective layer and the chargeable layer. The intermediate layer contains As in an increasing concentration gradient across the section of the layer from the chargeable layer to the surface protective layer. This graded As concentration causes the coefficient of thermal expansion to gradually decrease across the intermediate layer section in the direction from the chargeable layer to the surface protective layer.

Abstract: A photosensitive material for electrophotography is provided, which comprises in sequence an electroconductive substrate, a carrier transport layer composed of a selenium-arsenic alloy, a carrier generation layer composed of a selenium-tellurium alloy and a surface coating layer composed of a selenium-arsenic alloy. The present invention further relates to a photosensitive material having a carrier transport layer that is doped with iodine as well.

Abstract: A photoconductor for electrophotography has a unique electron injection-limiting layer of either pure selenium or a selenium-arsenic alloy containing less than 10 weight % arsenic formed between the carrier generation layer and the surface protective layer, which suppresses the transfer of electrons to the surface protective layer and prevents a drop in the electrostatic surface potential.

Abstract: A photosensitive material for electrophotography is provided, which comprises in sequence an electroconductive substrate, a carrier transport layer composed of a selenium-arsenic alloy, a carrier generation layer composed of a selenium-tellurium alloy and a surface coating layer composed of a selenium-arsenic alloy. The present invention further relates to a photosensitive material having a carrier transport layer that is doped with iodine as well.