Patent classifications
G03G5/1473
Photoreceptor for electrophotography and image forming apparatus employing the same
An electrophotographic photoreceptor includes a conductive support, a photosensitive layer on the conductive support, and a protective layer on the photosensitive layer. The protective layer includes a binder resin, metal oxide particles, and fluororesin particles. The metal oxide particles include, on a surface thereof, a first surface-treating agent including fluorine atoms, and a second surface-treating agent including a polymerizable reactive group and a hydrophobic group. At least some of the metal oxide particles are supported on a surface of the fluororesin particles. The fluororesin particles are fixed to the binder resin via the at least some of the metal oxide particles supported on the surface of the fluororesin particles.
ELECTROPHOTOGRAPHIC PHOTORECEPTOR AND IMAGE FORMING APPARATUS
Provided is an electrophotographic photoreceptor containing a conductive support having thereon a photosensitive layer and a protective layer located on the photosensitive layer, wherein the protective layer contains a polymerized and cured product of a composition incorporating: a polymerizable monomer, a polymerizable perfluoropolyether compound, and metal oxide particles surface-modified with a surface modifying agent containing a fluorine atom.
IMAGE FORMING APPARATUS
An image forming apparatus includes an image carrier that includes a conductive substrate, and a photosensitive layer and a surface protection layer; a developing device that includes an electrostatic image developer containing a toner, and develops the electrostatic image to form a toner image. The toner contains an amorphous polyester resin and has a weight average molecular weight Mw in a range of from 25,000 to 60,000, and a ratio of the weight average molecular weight Mw to a number average molecular weight Mn (Mw/Mn) is in a range of from 5 to 10. In the toner, a ratio of an absorbance for a wavelength of 1500 cm.sup.1 to an absorbance for a wavelength of 720 cm.sup.1 is 0.6 or less, and a ratio of an absorbance for a wavelength of 820 cm.sup.1 to the absorbance for a wavelength of 720 cm.sup.1 is 0.4 or less.
IMAGE FORMING METHOD AND IMAGE FORMING DEVICE
An image forming method forms an image by performing charging, exposing, developing, and transferring in a rotation direction of a rotationally driven photoreceptor, wherein the charging is performed by a roller charging method, exposing a surface of the photoreceptor to light and eliminating charges on the surface of the photoreceptor are included between the developing and the transferring, the photoreceptor includes at least a charge transporting layer and a protective layer laminated on the charge transporting layer on a conductive support, and energy of light for irradiation in the exposing the surface of the photoreceptor to light is in a range of 0.0001 to 500 W/mm.sup.2 on the surface of the photoreceptor.
ELECTROPHOTOGRAPHIC PHOTOSENSITIVE MEMBER, AND ELECTROPHOTOGRAPHIC APPARATUS AND PROCESS CARTRIDGE EACH INCLUDING THE ELECTROPHOTOGRAPHIC PHOTOSENSITIVE MEMBER
Provided is an electrophotographic photosensitive member, wherein a surface layer of the electrophotographic photosensitive member contains a copolymer of a hole-transportable compound having a polymerizable functional group and a compound represented by the following general formula (1).
Ar.sup.1L.sup.1-P.sup.1).sub.m(1)
ELECTROPHOTOGRAPHIC PHOTOSENSITIVE MEMBER, PROCESS CARTRIDGE, AND ELECTROPHOTOGRAPHIC APPARATUS
An electrophotographic photosensitive member includes an electroconductive support member and a photosensitive layer. The uppermost layer of the electrophotographic photosensitive member defines a surface layer, and the surface layer contains polytetrafluoroethylene particles, a charge transporting material, and polyvinyl acetal. The proportion of the polyvinyl acetal content to the polytetrafluoroethylene particles content in the surface layer is in the range of 0.1% by mass to 15.0% by mass, and the charge transporting material content in the surface layer is 35% by mass or more relative to the total mass of the surface layer.
Electrophotographic photosensitive member, method for manufacturing electrophotographic photosensitive member, process cartridge, and electrophotographic apparatus
An electrophotographic photosensitive member, in which occurrences of image defects are suppressed, and a method for manufacturing the electrophotographic photosensitive member are provided. In addition, a process cartridge and an electrophotographic apparatus, which include the electrophotographic photosensitive member, are provided. The surface layer of the electrophotographic photosensitive member contains a cured material, and the cured material is a copolymer of a hole transport compound having a chain-polymerizable functional group and a vinyl ester compound containing a long-chain alkyl group.
ELECTROPHOTOGRAPHIC PHOTORECEPTOR, IMAGE FORMING APPARATUS, IMAGE FORMING METHOD, PRODUCTION METHOD OF ELECTROPHOTOGRAPHIC PHOTORECEPTOR
An object of the present invention is achieved by an electrophotographic photoreceptor containing a conductive support sequentially laminated thereon with at least a photosensitive layer and a protective layer in that order, wherein the protective layer includes a cured composition having a radical polymerizable compound for a binder, a charge transport agent having a radical polymerizable functional group, and a photopolymerization initiator; the charge transport agent having a radical polymerizable functional group has a maximum absorption wavelength in the range of 40550 nm; and the charge transport agent having a radical polymerizable functional group and the photopolymerization initiator satisfy Formula (A),
G=Eox(D/D.sup.+)Ered(A.sup./A)E*0.2(eV). Formula (A):
Image forming apparatus and electrophotographic cartridge
The invention is to provide an image forming apparatus and an electrophotographic cartridge, which are free from problems of cleaning failure, filming, soiling, residual images (ghosts), fogging, density reduction, noise and the like and which can provide high-definition images even when a toner having a small particle size and having a high degree of circularity is used and even when a photoreceptor having a small outer diameter is used. An image forming apparatus comprising: an electrophotographic photoreceptor containing a conductive support and a photosensitive layer on the conductive support, a charging unit for charging the electrophotographic photoreceptor, an imagewise exposing unit for imagewise exposing the charged electrophotographic photoreceptor to form an electrostatic latent image thereon, a developing unit for developing the electrostatic latent image with a toner, and a transferring unit for transferring the toner from the electrophotographic photoreceptor to a receiving unit, wherein the outer diameter of the electrophotographic photoreceptor is 20 mm or less, the photosensitive layer contains a polyarylate resin, and the toner satisfies the specific requirements (1) and (2).
PHOTORECEPTOR FOR ELECTROPHOTOGRAPHY AND IMAGE FORMING APPARATUS EMPLOYING THE SAME
An electrophotographic photoreceptor includes a conductive support, a photosensitive layer on the conductive support, and a protective layer on the photosensitive layer. The protective layer includes a binder resin, metal oxide particles, and fluororesin particles. The metal oxide particles include, on a surface thereof, a first surface-treating agent including fluorine atoms, and a second surface-treating agent including a polymerizable reactive group and a hydrophobic group. At least some of the metal oxide particles are supported on a surface of the fluororesin particles. The fluororesin particles are fixed to the binder resin via the at least some of the metal oxide particles supported on the surface of the fluororesin particles.