Abstract: An electrophotographic photoconductor includes a conductive support; a charge generation layer provided on the conductive support; and a charge transport layer containing a charge transport material, a binder resin, and a highly branched polymer having a long-chain alkyl group or an alicyclic group, provided on the charge generation layer as an outermost layer. The electrophotographic photoconductor has excellent contamination resistance against sebum or the like, stable electrical characteristics even upon repeated use, as well as superior transfer resistance and gas resistance. A method for producing the electrophotographic photoconductor is disclosed, as well as an electrophotographic apparatus including the electrophotographic photoconductor.

Abstract: An electrophotographic photosensitive member capable of preventing the occurrence of interference fringe patterns when the member is installed in a device using coherent light as exposure light, without exerting a negative influence on electric characteristics, is disclosed. The electrophotographic photosensitive member includes an electrically conductive substrate; a photosensitive layer provided on the electrically conductive substrate; and an intermediate layer interposed between the photosensitive layer and the electrically conductive substrate. The intermediate layer is composed of a cyanine dye having a maximum absorption wavelength within a range of exposure light source wavelength of ±50 nm; metal oxide fine particles; and a thermosetting resin as a binder resin. The photosensitive layer may be a laminated photosensitive layer including a charge generating layer and a charge transport layer. An image forming apparatus that includes the electrophotographic photosensitive member is also disclosed.

Abstract: An electrophotographic photoconductor includes a conductive support; a charge generation layer provided on the conductive support; and a charge transport layer containing a charge transport material, a binder resin, and a highly branched polymer having a long-chain alkyl group or an alicyclic group, provided on the charge generation layer as an outermost layer. The electrophotographic photoconductor has excellent contamination resistance against sebum or the like, stable electrical characteristics even upon repeated use, as well as superior transfer resistance and gas resistance. A method for producing the electrophotographic photoconductor is disclosed, as well as an electrophotographic apparatus including the electrophotographic photoconductor.

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: 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: 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: 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 electrophotographic photoconductor that stabilizes electrical performances and prevents generation of image faults such as memories, irrespective of types of organic materials of resin binder and charge transport material, and variation of temperature and humidity of the operation environment. An electrophotographic photoconductor includes at least a photosensitive layer formed over a conductive substrate, wherein the photosensitive layer contains a cyclohexane dimethanol-diaryl ester compound represented by the formula (I): in formula (I), each of R1 through R10 represents independently, a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group of carbon number of from 1 to 5, a substituted or unsubstituted aryl group, or a substituted or unsubstituted alkoxy group of carbon number of from 1 to 5.

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 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: An electrophotographic photoconductor includes an undercoat layer and a photosensitive layer sequentially provided on a conductive substrate. The undercoat layer is mainly composed of a resin and contains a metal oxide. The resin is provided by mixing and polymerizing raw materials of aromatic dicarboxylic acid in a range of 0.1 to 10 mol %, two or more types of dicarboxylic acid other than the aromatic dicarboxylic acid, two or more types of diamine, and at least one type of cyclic amide compound. The resin exhibits an acid value and a base value each of at most 6.0 KOH mg/g. Advantageously, generation of secondary aggregates in the undercoat layer, which result in image defects such as black spots and fogging on a white field, is suppressed.

Abstract: An electrophotographic photoconductor and method that seldom generate cracks even while recycling a photoconductor drum and peripheral members or in a liquid developing process, and thereby produce excellent images. The electrophotographic photoconductor includes a conductive substrate and a photosensitive layer comprising a charge generation material and a charge transport material. The photosensitive layer comprises a resin binder of polyarylate resin having structural units represented by the following formula (I): In the formula, R1 and R2 represent a hydrogen atom, an alkyl group, a cycloalkyl group, or an aryl group. R1, R2, and a carbon atom bonding to the R1 and R2 together form a cyclic structure. The cyclic structure is bonded to no more than two arylene groups. Each of R3 through R10 being a hydrogen atom, an alkyl group, a fluorine atom, a chlorine atom, and a bromine atom. The values of m and n satisfy the equation 0.5<m/(m+n)<0.7.

Abstract: An electrophotographic photoconductor includes an undercoat layer and a photosensitive layer sequentially provided on a conductive substrate. The undercoat layer is mainly composed of a resin and contains a metal oxide. The resin is provided by mixing and polymerizing raw materials of aromatic dicarboxylic acid in a range of 0.1 to 10 mol %, two or more types of dicarboxylic acid other than the aromatic dicarboxylic acid, two or more types of diamine, and at least one type of cyclic amide compound. The resin exhibits an acid value and a base value each of at most 6.0 KOH mg/g. Advantageously, generation of secondary aggregates in the undercoat layer, which result in image defects such as black spots and fogging on a white field, is suppressed.

Abstract: An improved electrophotographic photosensitive device is disclosed. The device comprises a photosensitive layer coupled to a conductive substrate. The photosensitive layer preferably includes a vinyl chloride resin and the vinyl chloride resin preferably comprises an acid esterified vinyl chloride polymer having polymer hydroxy groups, epoxy groups and strong acid radicals as substituent groups, so that the epoxy groups and the hydroxy groups are partially esterified.

Abstract: An electrophotographic photoconductor and method that seldom generate cracks even while recycling a photoconductor drum and peripheral members or in a liquid developing process, and thereby produce excellent images. The electrophotographic photoconductor includes a conductive substrate and a photosensitive layer comprising a charge generation material and a charge transport material. The photosensitive layer comprises a resin binder of polyarylate resin having structural units represented by the following formula (I): In the formula, R1 and R2 represent a hydrogen atom, an alkyl group, a cycloalkyl group, or an aryl group. R1, R2, and a carbon atom bonding to the R1 and R2 together form a cyclic structure. The cyclic structure is bonded to no more than two arylene groups. Each of R3 through R10 being a hydrogen atom, an alkyl group, a fluorine atom, a chlorine atom, and a bromine atom. The values of m and n satisfy the equation 0.5<m/(m+n)<0.7.

Abstract: The object of the present invention is to provide an electrophotographic photoconductor that has sufficient resistance against ozone and exhibits improved stability in electrical characteristics. Another object of the invention is to provide a method for manufacturing such a photoconductor.

Abstract: The present invention provides an organic photosensitive body having improved stability of the electric property at times of repeated use and at times of changes in conditions of environmental usage. Such a photosensitive body prevents the generation of image defects of memory and the like. The present invention is a function-separated laminated organic photosensitive body equipped with a photosensitive layer, having a charge generating layer and a charge transport layer laminated in sequence on top of a conductive substrate, wherein the charge transport layer contains at least one type of electron transporting compound represented by the following general formulas (I) and (II): wherein R1-R29, A1, B1, and B2 are each as defined in the specification.

Abstract: A substrate for an electrophotographic photoconductor having an anodic oxidation film on the surface is subjected to two-step sealing treatment in which the substrate is sealing treated with nickel fluoride as a sealing agent, and then with nickel acetate as a sealing agent. Therefore, an electrophotographic photoconductor using the substrate for an electrophotographic photoconductor is small in charge potential difference between the first turn and the second turn and after, and does not generate a fogged image defect or the like even without preliminary charging before printing.