Patent classifications
G03G5/102
Electrophotographic photosensitive member, process cartridge and electrophotographic apparatus
There is provided an electrophotographic photosensitive member that can achieve both of an adequately high initial sensitivity as the electrophotographic photosensitive member and reduction in the fluctuation of a light portion potential at the time of repeated use. An electrophotographic photosensitive member includes a support, an electroconductive layer and a photosensitive layer in this order, wherein the electroconductive layer contains a binder material and a metal oxide particle; the metal oxide particle has a core material containing a titanium oxide, and a covering layer which covers the core material and contains the titanium oxide; and when the oxygen deficiency ratio of the metal oxide particle is represented by A, the oxygen deficiency ratio of the core material is represented by B, and the oxygen deficiency ratio of the covering layer is represented by C, the Expressions (1) and (2) are satisfied: A2% (1) and 10B<C (2).
Tubular metal body and electrophotographic photoreceptor
A tubular metal body includes a tubular part having an opening at one end in an axis direction; and a bottom part disposed at another end of the tubular part in the axis direction. The ratio (Rz1/Rz2) of a surface roughness Rz1 of an outer peripheral surface of the bottom part to a surface roughness Rz2 of an outer peripheral surface of a center portion of the tubular part in the axis direction is in a range of 2 or more and 4000 or less. A Vickers hardness HV1 of the outer peripheral surface of the bottom part is 5 HV or more and 27 HV or less smaller than a Vickers hardness HV2 of the outer peripheral surface of the center portion of the tubular part in the axis direction.
Electrophotographic photosensitive member, process cartridge, and electrophotographic apparatus
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.
Support for dip coating, electrophotographic photoreceptor, process cartridge, and image forming apparatus
A support for dip coating, wherein the inner peripheral surface at an end in the axial direction of the support has an arithmetic average roughness Ra of 0.26 m or less and a maximum height roughness Rz of 2.3 m or less.
ELECTROPHOTOGRAPHIC PHOTOSENSITIVE MEMBER, PROCESS CARTRIDGE AND ELECTROPHOTOGRAPHIC APPARATUS
The present disclosure provides an electrophotographic photosensitive member that can simultaneously achieve the suppression of the occurrence of the black spot in a charged portion and the suppression of the deterioration in sensitivity of an exposed portion, even after stored in a high-temperature and high-humidity environment. An electrophotographic photosensitive member includes an electro-conductive support, an undercoat layer, a charge generation layer and a charge transport layer in this order, wherein an atomic concentration ratio R of the oxygen atom to the aluminum atom on the surface of the electro-conductive support, as measured by energy dispersive X-ray spectroscopy, satisfies the following Expression (1):
1.6R(1) and the undercoat layer includes a titanium oxide particle that is surface-treated with a particular silane compound.
ELECTROPHOTOGRAPHIC PHOTORECEPTOR, PROCESS CARTRIDGE, AND IMAGE FORMING APPARATUS
An electrophotographic photoreceptor includes: a conductive substrate; an undercoating layer that contains inorganic particles surface-treated with a surface treatment agent, and is provided in contact with an outer peripheral surface of the conductive substrate; and a photosensitive layer provided on the undercoating layer, wherein, with respect to the outer peripheral surface of the conductive substrate, a proportion of an area being in contact with the inorganic particles is from 82% to 91%.
TUBULAR METAL BODY AND ELECTROPHOTOGRAPHIC PHOTORECEPTOR
A tubular metal body includes a tubular part having an opening at one end in an axis direction; and a bottom part disposed at another end of the tubular part in the axis direction. The ratio (Rz1/Rz2) of a surface roughness Rz1 of an outer peripheral surface of the bottom part to a surface roughness Rz2 of an outer peripheral surface of a center portion of the tubular part in the axis direction is in a range of 2 or more and 4000 or less. A Vickers hardness HV1 of the outer peripheral surface of the bottom part is 5 HV or more and 27 HV or less smaller than a Vickers hardness HV2 of the outer peripheral surface of the center portion of the tubular part in the axis direction.
ELECTROPHOTOGRAPHIC PHOTORECEPTOR AND IMAGE FORMING APPARATUS
An electrophotographic photoreceptor includes a cylindrical substrate; and a surface layer located on an outer surface of the cylindrical substrate. At least a substrate central portion in a cylindrical axial direction of the outer surface of the cylindrical substrate is formed as a rough surface, and a surface roughness of a surface-layer central portion in the cylindrical axial direction of an outer surface of the surface layer is larger than that of at least one of two surface-layer end portions in the cylindrical axial direction of the outer surface of the surface layer. An image forming apparatus includes the electrophotographic photoreceptor; and a peripheral member capable of contacting a surface of the electrophotographic photoreceptor.
Organic photoconductor drum having an overcoat containing nano metal oxide particles and method to make the same
An improved organic photoconductor drum having a protective overcoat layer and method to make the same is provided. The protective overcoat layer is prepared from a curable composition including nano metal oxide particles sized less than 400 nm in combination with an urethane acrylate resin having at least 6 functional groups.
Organic photoconductor drum having an overcoat containing nano metal oxide particles and method to make the same
An improved organic photoconductor drum having a protective overcoat layer and method to make the same is provided. The protective overcoat layer is prepared from a curable composition including nano metal oxide particles sized less than 400 nm in combination with an urethane acrylate resin having at least 6 functional groups.