Abstract: A charge transport material having reduced photodeterioration is disclosed to be an ethylene compound having an ethylene double bond site, having a structure in which four different substituents are substituted at the ethylene double bond site, and having general formula (I) below where R1, R2 and R3 are each independently a hydrogen atom, a halogen atom, an alkyl group of 1 to 6 carbons or an alkoxyl group of 1 to 6 carbons; R4 is phenyl or tolyl; and Ar is one group selected from the group consisting of naphthyl, biphenyl, anthryl, xylyl, and phenanthryl. An electrophotographic photoreceptor and process for producing the electrophotographic photoreceptor also are disclosed. The electrophotographic photoreceptor includes a conductive substrate; and a photosensitive layer provided on the conductive substrate that includes the charge transport material.

Abstract: A layered, positively-charged electrophotographic photoreceptor, a method for manufacturing the photoreceptor and an electrophotographic apparatus using the photoreceptor are disclosed. The layered, positively-charged electrophotographic photoreceptor includes a conductive support on which is provided a sequential stack composed of a charge transport layer containing at least a first hole transport material and a first binder resin; and a charge generation layer containing at least a charge generation material, a second hole transport material, an electron transport material, and a second binder resin, wherein the charge generation layer and the charge transport layer have a total amount of residual solvents that is 50 ?g/cm2 or less. The photoreceptor is highly sensitive, highly durable, and has excellent image qualities including low image defects from cracks generated due to image memory or contact contamination.

Abstract: An electrophotographic photoreceptor includes an electroconductive substrate; an undercoat layer provided on the electroconductive substrate and composed of: metal oxide fine particles including particles of at least one metal oxide and at least one organic compound provided on the particles of the at least one metal oxide as a surface treatment; and a copolymer resin synthesized by copolymerization of essential constituent monomers composed of a dicarboxylic acid, a diol, a triol and a diamine; and a photosensitive layer laminated on the undercoat layer. The undercoat layer permits (a) attaining stable electric potential characteristics in all environments ranging from low temperature and low humidity environments to high temperature and high humidity environments, (b) suppressing the occurrence of printing defects and density differences, and (c) simultaneously attaining transfer restorability and restorability from intense light-induced fatigue even in a wide variety of usages and operation environments.

Abstract: Provided is a photoreceptor for electrophotography, a process for producing the photoreceptor, and an electrophotographic apparatus that includes the photoreceptor. The photoreceptor has a photosensitive layer which contains a resin binder that is a copolymerized polyallylate resin. An electrophotographic apparatus having a photoreceptor drum that includes this photoreceptor has a reduced surface frictional resistance throughout the printing period from the beginning to after printing, thus reducing the amount of surface wear while producing satisfactory images.

Abstract: An electrophotographic photoconductor including, in the order recited: a conductive substrate; an undercoat layer provided on the conductive substrate; and a photoconductive layer provided on the undercoat layer and containing at least a phthalocyanine compound as a charge generation material and, as a resin binder, a polyvinyl acetal resin composed of a repeating unit represented by formula (1): where, in formula (1), R is a hydrogen atom, a methyl group, an ethyl group or a propyl group; x, y and z represent mol % of the respective structural units, where x+y+z=100; n is an integer from 1 to 5; a degree of acetalization (x+z) is 86 to 99 mol %; and a molar ratio (x:z) of the structural units is 95:5 to 50:50.

Abstract: Electrophotographic photoconductor including a conductive substrate; and a photosensitive layer provided on the conductive substrate and including at least a charge generation material; a charge transport material; and a resin binder including a copolymer polyarylate resin represented by general formula (I) below: and manufacturing method therefore. Good images with less cracking occurrence are obtained during recycling of a photosensitive drum and peripheral members thereof that includes the electrophotographic photoconductor, and also when a liquid development process is employed.

Abstract: In an electrophotographic photoreceptor having a photosensitive layer on an electroconductive substrate, the photosensitive layer is a positive-charging laminate comprising at least a charge transport layer and a charge generating layer laminated in that order, with the charge generating layer containing at least a resin binder, a charge generating agent, a space filler and an electron transport agent, while the charge transport layer contains at least, as a resin binder, polystyrene and a hole transport agent, and mineral oil of the charge transport layer is in an amount of 1% by mass or less of an amount of polystyrene. Thus, a highly durable and economic positive-charging multilayer electrophotographic photoreceptor and a manufacturing method therefor may be achieved.

Abstract: Provided is a photoreceptor for electrophotography, a process for producing the photoreceptor, and an electrophotographic apparatus that includes the photoreceptor. The photoreceptor has a photosensitive layer which contains a resin binder that is a copolymerized polyallylate resin. An electrophotographic apparatus having a photoreceptor drum that includes this photoreceptor has a reduced surface frictional resistance throughout the printing period from the beginning to after printing, thus reducing the amount of surface wear while producing satisfactory images.

Abstract: An electrophotographic photoreceptor includes an electroconductive substrate; an undercoat layer provided on the electroconductive substrate and composed of: metal oxide fine particles including particles of at least one metal oxide and at least one organic compound provided on the particles of the at least one metal oxide as a surface treatment; and a copolymer resin synthesized by copolymerization of essential constituent monomers composed of a dicarboxylic acid, a diol, a triol and a diamine; and a photosensitive layer laminated on the undercoat layer. The undercoat layer permits (a) attaining stable electric potential characteristics in all environments ranging from low temperature and low humidity environments to high temperature and high humidity environments, (b) suppressing the occurrence of printing defects and density differences, and (c) simultaneously attaining transfer restorability and restorability from intense light-induced fatigue even in a wide variety of usages and operation environments.

Abstract: A positive-charging electrophotography photoreceptor includes a laminated structure having a conductive supporting member, a charge transport layer formed of at least a hole transport material and a first binder resin, and a charge generation layer formed of at least a charge generation material, hole transport material, electron transport material, and second binder resin. The charge transport layer is disposed between the conductive supporting member and the charge generation layer. The content of the charge generation material in the charge generation layer is in a range exceeding 0.7 wt % and less than 3.0 wt % of the charge generation layer.

Abstract: Provided is an electrophotographic photoconductor that has good coating solution stability and metal oxide dispersibility, is free of image defects including ground fogging and black spots, and affords good image characteristics in various environments, as well as a manufacturing method therefore and a device including the same. The electrophotographic photoconductor includes a conductive substrate; an undercoat layer; and a photosensitive layer. The undercoat layer contains, as a main component, a resin obtained by polymerizing, as starting materials, an aromatic dicarboxylic acid, at least one aliphatic dicarboxylic acid having 8 or more carbon atoms, and at least one diamine having a cycloalkane structure, and further contains a metal oxide. The aromatic dicarboxylic acid in the resin is present in an amount that ranges from 0.1 to 10 mol %, and the resin has an acid value and a base value that are each no greater than 10 KOH mg/g.

Abstract: Electrophotographic photoconductor including a conductive substrate; and a photosensitive layer provided on the conductive substrate and including at least a charge generation material; a charge transport material; and a resin binder including a copolymer polyarylate resin represented by general formula (I) below: and manufacturing method therefore. Good images with less cracking occurrence are obtained during recycling of a photosensitive drum and peripheral members thereof that includes the electrophotographic photoconductor, and also when a liquid development process is employed.

Abstract: An ethylene compound having general formula (I) below: wherein R1, R2 and R3 are each independently a hydrogen atom, a halogen atom, an alkyl group of 1 to 6 carbons or an alkoxyl group of 1 to 6 carbons; R4 is an alkyl group of 1 to 3 carbons, phenyl or tolyl; and Ar is an aryl group of 7 to 20 carbons or a heterocyclic group, functions as a charge transport material in an electrophotographic photoreceptor. This compound suppresses photodeterioration, causes little light-induced fatigue, can prevent a rise in the residual potential associated with such light-induced fatigue, has stable properties as an electrophotographic photoreceptor even when used for an extended period of time, and is able to stably provide a satisfactory image.

Abstract: In an electrophotographic photoreceptor having a photosensitive layer on an electroconductive substrate, the photosensitive layer is a positive-charging laminate comprising at least a charge transport layer and a charge generating layer laminated in that order, with the charge generating layer containing at least a resin binder, a charge generating agent, a space filler and an electron transport agent, while the charge transport layer contains at least, as a resin binder, polystyrene and a hole transport agent, and mineral oil of the charge transport layer is in an amount of 1% by mass or less of an amount of polystyrene. Thus, a highly durable and economic positive-charging multilayer electrophotographic photoreceptor and a manufacturing method therefor may be achieved.

Abstract: An electrophotographic photoconductor which is a positive charging, single layer type organic photoconductor including a conductive substrate; and a photosensitive layer which is provided on the conductive substrate, which is a positive charging, single layer type organic photoconductor, and which is composed of at least one charge generation substance that contains a phthalocyanine pigment; a positive hole transport substance; an electron transport substance; and a binder that contains a polycarbonate resin with a polydialkylsilozane constructed of a repeated unit represented by formula (1). Toner consumption during repeated electrophotographic use is reduced and print defects including dirty background suppressed.

Abstract: An electrophotographic apparatus utilizes a photoconductor which avoids a concentration of electric field due to the voltage applied from the charging member to the irregular spot on the outer surface of the cylindrical conductive substrate, and as a result, electrical breakdown of the photosensitive layer is suppressed and lowering of the charged voltage is prevented, so that a critical printing fault, such as a black spot on the printed material, does not occur. The photoconductor includes a cylindrical conductive substrate and an organic photosensitive layer on the outer surface of the substrate, and is used in an electrophotographic system including a contact charging process, wherein the outer surface of the substrate is finished to a mirror surface by means of surface cutting.

Abstract: An electrophotographic photoconductor includes a conductive substrate having a photoconductive film thereon. The photoconductive film includes a layer containing a charge transport agent and a phosphonite compound, which acts as an antioxidant. Preferably, the phosphonite compound is diarylarylphosphonite. The layer that contains the charge transport preferably contains from 0.005 to 10 weight % of diarylarylphosphonite. The diarylarylphosphonite is preferably a compound selected from the group consisting of bis(2,4-di-tert-butylphenyl)phenylphosphonite, bis(2,6-di-tert-butylphenyl)phenylphosphonite and bis(2,6-di-tert-butyl-4-methylphenyl)phenylphosphonite.

Abstract: An electrophotographic process includes providing an organic photoconductor comprised of a charge generation layer and a charge transport layer containing a poly(alkanedioic acid 2,6-dimethoxyanthracene-9,10-diol ester) resin formed on a conductive substrate, and having a half decay exposure; and eliminating static from the organic photoconductor by illuminating the organic photoconductor with a static elimination light having a wavelength ranging from 520 to 680 nm and with a dose of the static elimination light which ranges from 3 to 10 times the half decay exposure of the organic photoconductor. Preferably, the wavelength of the static elimination light ranges from 550 to 650 nm.

Abstract: A photoconductor for electrography suitable for use in an electrophotography-applied apparatus of a wet development type includes a conductive substrate, a photosensitive layer provided on the conductive substrate, having a charge generating layer and a charge transporting layer provided on the charge generating layer and as an outermost layer of the photosensitive layer. Each of the charge generating layer and charge transporting layer contains an organic material as a main component. A subbing layer may be provided between the conductive substrate and the charge generating layer. The outermost layer of the photosensitive layer contains a poly(2,6-dimethoxyanthracene-9,10-diolyl alkanedioate) and a low molecular weight charge transporting material. The charge transporting layer covers the charge generating layer and the optional subbing layer including their end portions.

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.