Patent classifications
G03G5/0592
Electrophotographic photoreceptor, process cartridge, and image forming apparatus
An electrophotographic photoreceptor includes a conductive substrate and a photosensitive layer disposed on the conductive substrate. An outermost surface layer of the electrophotographic photoreceptor contains a fluorine-containing resin particle and a fluorine-based graft polymer having a fluorinated alkyl group. A ratio of an amount of a fluorine-based graft polymer separated from the fluorine-containing resin particle to a total amount of the fluorine-based graft polymer in the outermost surface layer is 15% or less.
ELECTROPHOTOGRAPHIC PHOTOSENSITIVE MEMBER, PROCESS CARTRIDGE, AND ELECTROPHOTOGRAPHIC IMAGE FORMING APPARATUS
An electrophotographic photosensitive member, which is suppressed in occurrence of fogging and is excellent in abrasion resistance. In the electrophotographic photosensitive member, an outermost surface layer of the electrophotographic photosensitive member comprises a polymerized product of a composition comprising at least a polyrotaxane and a monomer having a polymerizable reactive group, and a chain molecule of the polyrotaxane has two blocking groups at both terminals thereof, and a (meth)acryloyloxy group of a cyclic molecule of the polyrotaxane forms a bond.
ELECTROPHOTOGRAPHIC PHOTOSENSITIVE MEMBER, PROCESS CARTRIDGE AND ELECTROPHOTOGRAPHIC IMAGE FORMING APPARATUS
An electrophotographic photosensitive member having a support and a photosensitive layer on the support, wherein the electrophotographic photosensitive member comprises a surface layer comprising a polymerization product of a composition containing polyrotaxane and a charge transporting substance, and the polymerization product including a bond between the polyrotaxane and the charge transporting substance.
ELECTROPHOTOGRAPHIC PHOTORECEPTOR, PROCESS CARTRIDGE, AND IMAGE FORMING APPARATUS
An electrophotographic photoreceptor includes a conductive substrate and a photosensitive layer on the conductive substrate. The electrophotographic photoreceptor has an outermost surface layer that contains fluorine-containing resin particles and a fluorine-containing graft polymer. The fluorine-containing resin particles contain 0 or more and 30 or less carboxy groups per 10.sup.6 carbon atoms. The outermost surface layer has a dielectric constant of 3.75 or more and 3.90 or less. The contact angle of pure water on the outermost surface layer is 90° or more.
ELECTROPHOTOGRAPHIC PHOTOCONDUCTOR, AND ELECTROPHOTOGRAPHIC CARTRIDGE AND ELECTROPHOTOGRAPHIC IMAGING APPARATUS EMPLOYING THE SAME
An electrophotographic photoconductor in which a surface layer of a photosensitive layer or an overcoat layer has a glass transition temperature Tg greater than 100° C. and a hardness greater than 0.22 GPa. An electrophotographic cartridge and an electrophotographic imaging apparatus include the electrophotographic photoconductor. Flipping-over of a cleaning blade that comes into contact with the electrophotographic photoconductor may be effectively suppressed or prevented, the degree of freedom in terms of cleaning blade selection may be increased, and the possibility of causing high-frequency noise due to friction may be reduced.
Electrophotographic photoreceptor, process cartridge, and image-forming apparatus
An electrophotographic photoreceptor includes a conductive substrate and a photosensitive layer disposed on the conductive substrate. An outermost surface layer of the electrophotographic photoreceptor contains fluorine-containing resin particles and a fluorine-containing graft polymer having a fluorinated alkyl group. In an infrared absorption spectrum of the fluorine-containing graft polymer, a ratio of a peak area in a wavenumber range of from 1,020 cm.sup.−1 to 1,308 cm.sup.−1 to a peak area in a wavenumber range of from 1,673 cm.sup.−1 to 1,779 cm.sup.−1 is 2.7 or more and 4.8 or less.
ELECTROPHOTOGRAPHIC PHOTORECEPTOR, PROCESS CARTRIDGE, AND IMAGE FORMING APPARATUS
An electrophotographic photoreceptor includes a conductive substrate and a photosensitive layer on the conductive substrate. The outermost surface layer of the electrophotographic photoreceptor contains fluorine-containing resin particles, a fluorine graft polymer, and an acidic compound having an acid dissociation constant (pKa) of 3 or less in water at 25° C. The amount of the acidic compound relative to the outermost surface layer is 100 ppm or more and 10000 ppm or less.
Electrophotographic photosensitive member, process cartridge, and electrophotographic apparatus
An electrophotographic photosensitive member including: a support; and a surface layer, wherein the surface layer contains a cured product of a composition containing a curable hole-transport compound, a specific fluorine-atom-containing compound, and a specific polymerizable compound.
Electrophotographic photosensitive member, process cartridge, and electrophotographic apparatus
Provided is an electrophotographic photosensitive member improved both in wear resistance and in image unevenness. The electrophotographic photosensitive member includes a support, and a photosensitive layer and a surface layer on the support, wherein the surface layer is a cured product of a composition containing a compound represented by the formula (A) and a charge-transporting substance having at least one reactive functional group selected from the group consisting of a hydroxy group, a methoxy group, an amino group, a thiol group, and a carboxyl group.
Electrophotographic image forming apparatus and process cartridge
Provided are an electrophotographic apparatus and a process cartridge each capable of suppressing the occurrence of a black spot (white background contamination) in an output image under a low-temperature and low-humidity environment. The electrophotographic apparatus includes: an electrophotographic photosensitive member including a support, a photosensitive layer, and a protective layer in the stated order; an exposing device; a developing device; and a cleaning device, wherein the protective layer has a triarylamine structure and a specific structure at a ratio in a specific range, and a toner contains toner particles each containing at least a resin, and an external additive. The toner has a volume-average particle diameter of 7 μm or more. The external additive contains a compound containing a titanium atom. The ratio of the mass of the compound containing a titanium atom to the total mass of the toner is 0.6 mass % or more.