Abstract: Disclosed is a cylindrical electrophotographic photosensitive member having a region A along an outer surface and a region B along the outer surface. In this electrophotographic photosensitive member, the region A is located on an end side in an axial direction of the electrophotographic photosensitive member relative to the region B, the region A has a specific groove provided on the outer surface of the electrophotographic photosensitive member, an area ratio a1 of the groove is 65% to 100%, the region B has specific concave portions provided on the outer surface of the electrophotographic photosensitive member, and an area ratio a2 of the concave portion is 5% to 65%.

Abstract: Disclosed is a cylindrical electrophotographic photosensitive member having a region A along an outer surface and a region B along the outer surface. In this electrophotographic photosensitive member, the region A is located on an end side in an axial direction of the electrophotographic photosensitive member relative to the region B, the region A has a specific groove provided on the outer surface of the electrophotographic photosensitive member, an area ratio a1 of the groove is 65% to 100%, the region B has specific concave portions provided on the outer surface of the electrophotographic photosensitive member, and an area ratio a2 of the concave portion is 5% to 65%.

Abstract: There is provided a method for controlling an electrophotographic apparatus including forming a first measurement image by performing first halftone processing on image data, forming a second measurement image by performing second halftone processing different from the first halftone processing on the image data, measuring densities of the first measurement image and the second measurement image, calculating a density difference between each of densities of the measurement images, determining whether the density difference satisfies a predetermined reference value, and applying a surface treatment on an electrophotographic photosensitive member if the density difference does not satisfy the reference value, during a non-image formation period.

Abstract: Provided is a cylindrical electrophotographic photosensitive member, including a concave/convex portion forming region in which at least one of concave portions and convex portions are formed on a surface of the electrophotographic photosensitive member from a central portion to both end portions in an axial direction of the electrophotographic photosensitive member, wherein a maximum value Lmax and a minimum value Lmin of a distance L from the central portion to one end portion of the concave/convex portion forming region in the axial direction of the surface of the electrophotographic photosensitive member satisfy a specific relation.

Abstract: There is provided a method for controlling an electrophotographic apparatus including forming a first measurement image by performing first halftone processing on image data, forming a second measurement image by performing second halftone processing different from the first halftone processing on the image data, measuring densities of the first measurement image and the second measurement image, calculating a density difference between each of densities of the measurement images, determining whether the density difference satisfies a predetermined reference value, and applying a surface treatment on an electrophotographic photosensitive member if the density difference does not satisfy the reference value, during a non-image formation period.

Abstract: Provided is a cylindrical electrophotographic photosensitive member, including a concave/convex portion forming region in which at least one of concave portions and convex portions are formed on a surface of the electrophotographic photosensitive member from a central portion to both end portions in an axial direction of the electrophotographic photosensitive member, wherein a maximum value Lmax and a minimum value Lmin of a distance L from the central portion to one end portion of the concave/convex portion forming region in the axial direction of the surface of the electrophotographic photosensitive member satisfy a specific relation.

Abstract: The present invention provides an electrophotographic photosensitive member which has a substrate, a photoconductive layer and a surface layer formed from hydrogenated amorphous silicon carbide in this order. The average value of the carbon content (C/(C+Si)) of the surface layer formed from the hydrogenated amorphous silicon carbide is set at 0.90 or more and less than 1.00, and the average value of the hydrogen content (H/(H+C+Si)) is set at 0.40 or less; and when the average value of the ratios of the sum of a Si—O bond and an O—Si—O bond in the outermost surface region that constitutes a range within a depth of 5 nm or less from the outermost surface of the surface layer is represented by a, and an average value of the silicon content (Si/(C+Si)) is represented by b, 0.015?a*b?0.090 holds.

Abstract: An average value of a hydrogen content ratio of a surface layer made of hydrogenated amorphous carbon is set to be 0.40 or less and a maximum value of an sp2 bonding ratio in an outermost surface region of the surface layer made of the hydrogenated amorphous carbon is set to be 0.50 or less.

Abstract: An average value of a hydrogen content ratio of a surface layer made of hydrogenated amorphous carbon is set to be 0.40 or less and a maximum value of an sp2 bonding ratio in an outermost surface region of the surface layer made of the hydrogenated amorphous carbon is set to be 0.50 or less.

Abstract: The present invention provides an electrophotographic photosensitive member which has a substrate, a photoconductive layer and a surface layer formed from hydrogenated amorphous silicon carbide in this order. The average value of the carbon content (C/(C+Si)) of the surface layer formed from the hydrogenated amorphous silicon carbide is set at 0.90 or more and less than 1.00, and the average value of the hydrogen content (H/(H+C+Si)) is set at 0.40 or less; and when the average value of the ratios of the sum of a Si—O bond and an O—Si—O bond in the outermost surface region that constitutes a range within a depth of 5 nm or less from the outermost surface of the surface layer is represented by a, and an average value of the silicon content (Si/(C+Si)) is represented by b, 0.015?a*b?0.090 holds.

Abstract: Provided is an electrophotographic photosensitive member that improves the sensitivity characteristic and high-humidity deletion resistance, and achieves compatibility between a high image-resolving power and the suppression of an image memory. The electrophotographic photosensitive member comprises an electrophotographic photosensitive member, including: a photoconductive layer; and a surface layer comprising hydrogenated amorphous silicon carbide on the photoconductive layer, in which: a ratio (C/(Si+C)) of a number of carbon atoms (C) to a sum of a number of silicon atoms (Si) and the number of the carbon atoms (C) in the surface layer is 0.50 or more and 0.65 or less; a sum of an atom density of the silicon atoms and an atom density of the carbon atoms in the surface layer is 6.60×1022 atoms/cm3 or more; and a defect density of the surface layer determined by electron spin resonance measurement is 9.0×1018 spins/cm3 or more and 2.2×1019 spins/cm3 or less.

Abstract: An electrophotographic photosensitive member is configured such that the average value Hx_ave of the content of hydrogen atoms in a central portion area of a photoconductive layer in a cylindrically axial direction thereof, the content Hx of the hydrogen atoms at an arbitrary point in the central portion area, the average value Hy_ave of the content of the hydrogen atoms in an end area of the photoconductive layer in the cylindrically axial direction thereof, and the content Hy of the hydrogen atoms at an arbitrary point in the end area satisfy 10?Hx_ave?30, Hx<Hy, |Hx_ave?Hx|?5, and 2?Hy_ave?Hx_ave?12.

Abstract: The present invention provides an electrophotographic photosensitive member including a conductive substrate, a photoconductive layer on the conductive substrate, and a surface layer made of hydrogenated amorphous silicon carbide on the photoconductive layer. A ratio (C/(Si+C)) in the surface layer is 0.61 to 0.75, both inclusive, an Si+C atom density in the surface layer is 6.60×1022 atoms/cm3 or more, and an arithmetic average roughness Ra of the surface layer is 0.029 ?m to 0.500 ?m, both inclusive.

Abstract: An electrophotographic photosensitive member has a conductive substrate, a photoconductive layer formed on the conductive substrate, and a surface layer formed on the photoconductive layer. The photoconductive layer is formed of an amorphous material having chiefly silicon atoms. The surface layer has aluminum atoms, nitrogen atoms and oxygen atoms, where the nitrogen atoms are in a content of from 80 atom % or more to 95 atom % or less, and the oxygen atoms are in a content of from 1 atom % or more to 30 atom % or less, based on the aluminum atoms in the surface layer.

Abstract: An electrophotographic photosensitive member is configured such that the average value Hx_ave of the content of hydrogen atoms in a central portion area of a photoconductive layer in a cylindrically axial direction thereof, the content Hx of the hydrogen atoms at an arbitrary point in the central portion area, the average value Hy_ave of the content of the hydrogen atoms in an end area of the photoconductive layer in the cylindrically axial direction thereof, and the content Hy of the hydrogen atoms at an arbitrary point in the end area satisfy 10?Hx_ave?30, Hx<Hy, |Hx_ave?Hx|?5, and 2?Hy_ave?Hx_ave?12. An electrophotographic apparatus having the electrophotographic photosensitive member is provided.

Abstract: The present invention provides an electrophotographic photosensitive member including: a conductive substrate; a photoconductive layer on the conductive substrate; and a surface layer made of hydrogenated amorphous silicon carbide on the photoconductive layer, wherein (C/(Si+C)) in the surface layer is 0.61 to 0.75 (both inclusive), Si+C atom density in the surface layer is 6.60×1022 atoms/cm3 or more, and arithmetic average roughness Ra of the surface layer is 0.029 ?m to 0.500 ?m (both inclusive), and an electrophotographic apparatus including the electrophotographic photosensitive member.

Abstract: An electrophotographic photosensitive member has a conductive substrate, a photoconductive layer formed on the conductive substrate, and a surface layer formed on the photoconductive layer. The photoconductive layer is formed of an amorphous material having chiefly silicon atoms. The surface layer has aluminum atoms, nitrogen atoms and oxygen atoms, where the nitrogen atoms are in a content of from 80 atom % or more to 95 atom % or less, and the oxygen atoms are in a content of from 1 atom % or more to 30 atom % or less, based on the aluminum atoms in the surface layer.

Abstract: An electrophotographic photosensitive member is provided minimizing the absorption of image exposure having a short wavelength in a surface layer and keeping good electrophotographic properties including resolving power. The electrophotographic photosensitive member includes a conductive substrate, and a photoconductive layer and a surface region layer sequentially superimposed on the conductive substrate. The surface region layer is composed of a non-single-crystal silicon nitride film containing an Group element in the periodic table and a carbon atom and using at least a silicon atom and a nitrogen atom as base materials. In the surface region layer, the Group 13 element content with respect to the total amount of constituent atoms has distribution having at least two local maximum values in the thickness direction, and an the average concentration of nitrogen atoms is 30 atm % to 70 atm %.

Abstract: To provide a high-image-quality electrophotographic photosensitive member having a high sensitivity for a wavelength close to 380 to 500 nm, remarkable image resolution property in which absorption of the wavelength is hardly recognized, working-environment characteristic and high safety and superior in abrasion resistance and fabrication easiness and reducing optical memories and an electrophotographic apparatus using the high-image-quality electrophotographic photosensitive member. In the case of an electrophotographic photosensitive member having a substrate, photoconductive layer formed on the substrate and surface layer formed on the photoconductive layer and using silicon and nitrogen atoms as base material and containing an amorphous material containing at least oxygen atoms, the surface layer contains nitrogen atoms as an average concentration shown by the following expression (1) and contains oxygen atoms by the maximum value Omax of the number of oxygen atoms in the thickness direction: 0.

Abstract: An electrophotographic photosensitive member is provided which can keep at a minimum the absorption of image exposure light of 380 to 500 nm in wavelength in its surface layer and concurrently can satisfactorily keep electrophotographic properties including resolving power. The electrophotographic photosensitive member has a substrate, and a photoconductive layer and a surface layer in this order provided on the substrate. The surface layer includes an amorphous material composed chiefly of silicon atoms and nitrogen atoms and containing at least oxygen atoms and carbon atoms, and the ratios of the numbers of the respective oxygen atoms, carbon atoms and nitrogen atoms to the total number of oxygen atoms, carbon atoms and nitrogen atoms contained in the amorphous material are each within a specific range.