Abstract: An electrophotographic photoreceptor including a photosensitive layer on an electroconductive substrate, wherein nitrate ion is present on the surface of the photosensitive layer in an amount of from 50 to 300 &mgr;g per 1 m2 of the surface of the photosensitive layer when the nitrate ion is determined by an ion chromatographic method. Preferably a material having a fluorine atom and a carbon atom or a fatty acid metal salt such as zinc stearate is further present on the surface of the photosensitive layer such that the F/C ratio is from 0.05 to 0.5 or the Zn/C ratio is from 0.001 to 0.1. An image forming apparatus using the photoreceptor is also provided.

Abstract: An electrophotographic photoreceptor including at least an electroconductive substrate; and a photosensitive layer overlying the electroconductive substrate and including at least a charge generation layer; a charge transport layer; and a protective layer including a filler, wherein the filler is dispersed in the protective layer so as to occupy an area of from 3 to 5% of a cross section of the protective layer; the filler has particle diameter distribution having a peak at a diameter of from 0.2 to 0.3 &mgr;m; and the particles of the filler having a particle diameter of not less than 0.3 &mgr;m occupies an area of from 10 to 30% of the area of all the filler in the cross section of the protective layer.

Abstract: An electrophotographic drum-shaped photoconductor has an electroconductive support and a photoconductive layer formed thereon, with a lubricating material being applied to the surface thereof in the shape of a plurality of bands spaced therebetween, constituting band-shaped lubricating material applied areas, extending along a circumference of the drum-shaped photoconductor in the direction perpendicular or substantially perpendicular to an axis of rotation of the drum-shaped photoconductor. An electrophotographic image formation method and an image forming apparatus employing the above-mentioned drum-shaped photoconductor are also disclosed.

Abstract: An electrophotographic photoreceptor including a photosensitive layer on an electroconductive substrate, wherein nitrate ion is present on the surface of the photosensitive layer in an amount of from 50 to 300 &mgr;g per 1 m2 of the surface of the photosensitive layer when the nitrate ion is determined by an ion chromatographic method. Preferably a material having a fluorine atom and a carbon atom or a fatty acid metal salt such as zinc stearate is further present on the surface of the photosensitive layer such that the F/C ratio is from 0.05 to 0.5 or the Zn/C ratio is from 0.001 to 0.1. An image forming apparatus using the photoreceptor is also provided.

Abstract: An image forming apparatus including a photoreceptor configured to bear an electrostatic latent image while rotating in a direction, wherein the photoreceptor includes an electroconductive substrate, a photosensitive layer located overlying the substrate, and a protective layer located overlying the photosensitive layer and including a filler; a latent image former configured to form the electrostatic latent image on the photoreceptor; an image developer configured to develop the electrostatic latent image with a developer including a toner; an image transfer device configured to transfer the toner image onto a receiving material; a cleaner configured to remove the toner remaining on the surface of the photoreceptor while contacting the surface of the photoreceptor; and a surface condition controller configured to control a surface condition of the photoreceptor.

Abstract: An electrophotographic photoreceptor including an electroconductive substrate and a photoreceptive layer, which is formed overlying the substrate, wherein the photoreceptive layer includes a charge carrier generation layer including a charge carrier generation material and a charge carrier transport layer including a charge carrier transport material, and wherein when an electric field of from 2.5×105 V/cm to 5.5×105 V/cm is applied to the charge carrier transport layer, the relationship, tCTL/&mgr;CTL≦1.5×103 V·s/m, is satisfied, wherein tCTL represents a thickness of the charge carrier transport layer and &mgr;CTL represents a charge mobility of the charge carrier transport layer.

Abstract: An image forming apparatus including a photoreceptor having an image forming portion; a charging roller having a gap forming member on both ends thereof to form a gap between the photoreceptor and the charging roller and configured to charge the photoreceptor, wherein the gap forming members do not contact the image forming portion, and wherein the relationship t≧2g is satisfied; a light irradiator configured to form a latent image in the image forming portion; an image developer configured to form a toner image on the photoreceptor; and an image transferer configured to transfer the toner image onto a receiving material, wherein g is the gap and t represents a distance between an inside edge of one of the gap forming members and one of the two ends of the image forming portion closer to the inside edge of the gap forming member.

Abstract: An electrophotographic photoreceptor including at least an electroconductive substrate; and a photosensitive layer overlying the electroconductive substrate and including at least a charge generation layer; a charge transport layer; and a protective layer including a filler, wherein the filler is dispersed in the protective layer so as to occupy an area of from 3 to 5% of a cross section of the protective layer; the filler has particle diameter distribution having a peak at a diameter of from 0.2 to 0.3 &mgr;m; and the particles of the filler having a particle diameter of not less than 0.3 &mgr;m occupies an area of from 10 to 30% of the area of all the filler in the cross section of the protective layer.

Abstract: An electrophotographic photoreceptor including an electroconductive substrate; a photosensitive layer located overlying the electroconductive substrate and including a resin; and a surface layer including a filler and a binder resin, wherein the surface layer and the photosensitive layer have a continuous structure, and wherein the surface layer satisfies the following relationship: &sgr;≦D/5, wherein D represents an average of maximum thicknesses of the surface layer in units of micrometers in 20 segments of 5 &mgr;m wide when a portion of a cross section of the photoreceptor of 100 &mgr;m wide is divided into the 20 segments, and &sgr; represents a standard deviation of the 20 maximum thicknesses.

Abstract: An image forming apparatus including a photoreceptor having an image forming portion; a charging roller having a gap forming member on both ends thereof to form a gap between the photoreceptor and the charging roller and configured to charge the photoreceptor, wherein the gap forming members do not contact the image forming portion, and wherein the relationship t≧2g is satisfied; a light irradiator configured to form a latent image in the image forming portion; an image developer configured to form a toner image on the photoreceptor; and an image transferer configured to transfer the toner image onto a receiving material, wherein g is the gap and t represents a distance between an inside edge of one of the gap forming members and one of the two ends of the image forming portion closer to the inside edge of the gap forming member.

Abstract: A lubricity-imparting unit for imparting lubricity to a surface of an electrophotographic photoconductor, which is in contact with the surface of the photoconductor, wherein at least a surface of the lubricity-imparting unit which comes into contact with the surface of the photoconductor includes a flexible lubricating material, and has a length at least capable of covering an image formation region of the electrophotographic photoconductor lengthwise. An image formation apparatus and an image formation method using this lubricity-imparting unit are described.

Abstract: An electrophotographic photoreceptor including a photosensitive layer on an electroconductive substrate, wherein nitrate ion is present on the surface of the photosensitive layer in an amount of from 50 to 300 &mgr;g per 1 m2 of the surface of the photosensitive layer when the nitrate ion is determined by an ion chromatographic method. Preferably a material having a fluorine atom and a carbon atom or a fatty acid metal salt such as zinc stearate is further present on the surface of the photosensitive layer such that the F/C ratio is from 0.05 to 0.5 or the Zn/C ratio is from 0.001 to 0.1. An image forming apparatus using the photoreceptor is also provided.

Abstract: In an image forming apparatus of the type sequentially executing charging, exposure, development and image transfer, a device for applying a lubricant to the surface of an image carrier includes a lubricant applying member rotatable in contact with the image carrier for applying, at a position where the lubricant applying member contacts the image carrier, the lubricant to the surface of the image carrier while deforming its contour in accordance with a bite of the surface of the image carrier. A lubricant feeding unit feeds the lubricant to the lubricant applying member and includes a lubricant providing unit having a preselected thickness t. The surface of the image carrier bites into the lubricant applying member by an amount T while the lubricant providing unit bites into the lubricant applying member by an amount t' smaller than the amount T, but substantially equal to or slightly greater than the thickness t.

Abstract: An electrophotographic photoconductor including a photoconductive layer which is formed overlying an electroconductive substrate and which includes at least a charge transporting polymer material, wherein the photoconductive layer has a water vapor permeability not greater than about 200 g.multidot.m.sup.-2 .multidot.24 h.sup.-1. The photoconductive layer may be a functionally separated photoconductive layer including a charge generating layer and a charge transporting layer which is formed overlying the charge generating layer and which includes the charge transporting polymer material, wherein the charge transporting layer has a water vapor permeability not greater than about 200 g.multidot.m.sup.-2 .multidot.24 h.sup.-1.

Abstract: An image forming apparatus comprising a lubricant supplying device which supplies a lubricant to a rotating image carrier, wherein the lubricant comprises at least one of low molecular weight polytetrafluoroethylene, a fluorine-containing resin including a filler, polytetrafluoroethylene which has been subjected to heat or radiation decomposition treatment, a fluorine-containing resin which has been prepared by a compression molding method, and a porous fluorine-containing resin. The lubricant preferably has a concave portion on the surface thereof contacting the image carrier. The lubricant is preferably disposed so that an acute angle formed by a line parallel to a compression direction of the lubricant, during the compression molding of the lubricant, and a line parallel to a moving direction of the image carrier, is from about 45 to about 90.degree..

Abstract: An electrophotographic photoconductor including a photoconductive layer which is formed overlying an electroconductive substrate and which includes at least a charge transporting polymer material, wherein the photoconductive layer has a water vapor permeability not greater than about 200 g.multidot.m.sup.-2 .multidot.24 h.sup.-1. The photoconductive layer may be a functionally separated photoconductive layer including a charge generating layer and a charge transporting layer which is formed overlying the charge generating layer and which includes the charge transporting polymer material, wherein the charge transporting layer has a water vapor permeability not greater than about 200 g.multidot.m.sup.2 .multidot.24 h.sup.-1.

Abstract: An organic electroluminescent element having an anode, a cathode, and an organic compound layer provided between the electrodes, the organic compound layer containing an oxadiazole compound of formula (I) or (II): ##STR1## wherein A.sup.1 to A.sup.6 are each an aromatic hydrocarbon group or an aromatic heterocyclic group which may have a substituent; X is a hydrogen atom or a fluorine atom; R.sup.1 and R.sup.2 are each a hydrogen atom, a halogen atom, or an alkyl group which may have a substituent, or an alkoxyl group which may have a substituent; and R.sup.3, R.sup.4 and R.sup.5 are each a hydrogen atom, a halogen atom, an alkyl group which may have a substituent, an alkoxyl group which may have a substituent, or hydroxyl group.

Abstract: An organic electroluminescent element having an anode, a cathode, and an organic compound layer provided between the electrodes, the organic compound layer containing an oxadiazole compound of formula (I) or (II): ##STR1## wherein A.sup.1 to A.sup.6 are each an aromatic hydrocarbon group or an aromatic heterocyclic group which may have a substituent; X is a hydrogen atom or a fluorine atom; R.sup.1 and R.sup.2 are each a hydrogen atom, a halogen atom, or an alkyl group which may have a substituent, or an alkoxyl group which may have a substituent; and R.sup.3, R.sup.4 and R.sup.5 are each a hydrogen atom, a halogen atom, an alkyl group which may have a substituent, an alkoxyl group which may have a substituent, or hydroxyl group.

Abstract: An electroluminescent device is composed of a negative electrode, a positive electrode, and an organic compound layer which is interposed between the negative electrode and the positive electrode and includes at least one oxadiazole compound with a plurality of aryl oxadiazole structures. Novel oxadiazole compounds for use in the electroluminescent device and a method of producing the oxadiazole compounds are disclosed.

Abstract: An electroluminescent device is composed of a negative electrode, a positive electrode, and an organic compound layer which is interposed between the negative electrode and the positive electrode and includes at least one oxadiazole compound with a plurality of aryl oxadiazole structures. Novel oxadiazole compounds for use in the electroluminescent device and a method of producing the oxadiazole compounds are disclosed.