Patent classifications
G03G5/0564
Electrophotographic photosensitive member, process cartridge, and electrophotographic apparatus
The electrophotographic photosensitive member includes an undercoat layer and a surface layer on or above a support in this order, in which the undercoat layer contains metal oxide particles and a specific binder resin, the surface layer contains a charge transporting substance, fluororesin particles, and a specific binder resin, an arithmetic average roughness Ra of a surface of the undercoat layer is 0.15 m or less, a refractive index (a) of the metal oxide particles and a refractive index (b) of the binder resin contained in the undercoat layer satisfy a specific relationship, and a refractive index (c) of the binder resin contained in the surface layer and a refractive index (d) of the fluororesin particles satisfy a specific relationship.
ELECTROPHOTOGRAPHIC PHOTOSENSITIVE MEMBER, PROCESS CARTRIDGE, AND IMAGE FORMING APPARATUS
An electrophotographic photosensitive member includes a conductive substrate and a photosensitive layer of a single layer. The photosensitive layer contains a charge generating material, a binder resin, a hole transport material, and an electron transport material. The binder resin includes a polyester resin and a polycarbonate resin. The polyester resin includes a first repeating unit represented by general formula (1) shown below and a second repeating unit represented by general formula (2) shown below. The polycarbonate resin includes a third repeating unit represented by general formula (3) shown below and a fourth repeating unit represented by general formula (24) shown below.
##STR00001##
A content percentage of the polyester resin in the photosensitive layer is at least 0.3% by mass and no greater than 7.0% by mass.
Electrophotographic photosensitive member, process cartridge, and image forming apparatus
An electrophotographic photosensitive member includes a photosensitive layer of a single layer. The photosensitive layer contains a charge generating material, a hole transport material, an electron transport material, and a binder resin. An optical response time is 0.05 milliseconds or longer and 0.85 milliseconds or shorter. The optical response time is a time from irradiation of a surface of the photosensitive layer charged to +800 V with pulse light having a wavelength of 780 nm to decay of a surface potential of the photosensitive layer from +800 V to +400 V. The pulse light has an intensity that allows the surface potential of the photosensitive layer to decay to +200 V from +800 V after 400 milliseconds elapse from the irradiation of the surface of the photosensitive layer charged to +800 V with the pulse light. The photosensitive layer has a Martens hardness at 50 C. of at least 160 N/mm.sup.2.
Bis-butadiene derivative and electrophotographic photosensitive member
A bis-butadiene derivative is represented by general formula (1) shown below. ##STR00001##
In general formula (1), Ra, Rb, and Rc each represent, independently of one another, an alkyl group having a carbon number of at least 1 and no greater than 8 or an alkoxy group having a carbon number of at least 1 and no greater than 8. l and m each represent, independently of one another, an integer of at least 0 and no greater than 5. n represents an integer of at least 0 and no greater than 4. Chemical groups Ra may be the same as or different from each other. Chemical groups Rb may be the same as or different from each other. Chemical groups Rc may be the same as or different from each other.
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.
Polycarbonate resin, method for producing polycarbonate resin, coating liquid, electrophotographic photoreceptor, and electrophotography device
A polycarbonate resin has a structure represented by a formula (1) and a yellow index (YI) of 30 or less in a solid form, ##STR00001##
ELECTROPHOTOGRAPHIC PHOTORECEPTOR, PRODUCTION METHOD THEREOF, AND ELECTROPHOTOGRAPHIC APPARATUS
An electrophotographic photoreceptor includes an electroconductive substrate; and a photosensitive layer that is formed on the electroconductive substrate and that contains an inorganic oxide and a lubricant resin. When light having a wavelength of 780 nm is irradiated onto a slurry containing 20% by mass of the inorganic oxide in a predetermined solvent to provide an inorganic oxide slurry, the inorganic oxide slurry has a luminous transmittance that is 40% or more. The photosensitive layer may be a negatively-charged laminate-type photosensitive layer, a monolayer type photosensitive layer, or a positively-charged laminate-type photosensitive layer. The electrophotographic photoreceptor is less worn upon long-term use, allows no filming, and can realize stable images. A method for producing the electrophotographic photoreceptor and an electrophotographic apparatus including the electrophotographic photoreceptor are disclosed.
RESIN COMPOSITION, ELECTROPHOTOGRAPHIC PHOTOSENSITIVE MATERIAL, AND ELECTROPHOTOGRAPHIC DEVICE
A resin composition includes: a polycarbonate copolymer resin represented by a formula (1); and a polycarbonate resin having a repeating unit represented by a formula (2). Provided that a total of the polycarbonate copolymer resin represented by the formula (1) and the polycarbonate resin having the repeating unit represented by the formula (2) is defined as 100 parts by mass, a content of the polycarbonate copolymer resin represented by the formula (1) is in a range from 50 parts by mass to 95 parts by mass,
##STR00001##
Electrophotographic photoconductor, method of manufacturing the same, and electrophotographic apparatus
Provided is a photoconductor for electrophotography having high sensitivity, low residual potential, and good wear resistance and contamination resistance, and that is less likely to cause light-induced fatigue and filming, and also exhibits good potential stability before and after repeated printing, even without a surface protective layer formed on a photosensitive layer. Provided also are a process of producing the photoconductor and an electrophotographic apparatus. The photoconductor for electrophotography may be a single-layer-type photoconductor or a multi-layer-type photoconductor and includes a conductive substrate and a photosensitive layer formed on the conductive substrate and including a hole transport material having a structure represented by general formula (1) below; a binder resin having a repeating structure represented by general formula (2) below; and at least one electron transport material having a structure represented by general formulae (ET1) to (ET3) below: ##STR00001##
FLUORINE-CONTAINING RESIN PARTICLE, COMPOSITION, LAYER-SHAPED ARTICLE, ELECTROPHOTOGRAPHIC PHOTORECEPTOR, PROCESS CARTRIDGE, AND IMAGE FORMING APPARATUS
A fluorine-containing resin particle contains 0 or more and 30 or less carboxyl groups per 10.sup.6 carbon atoms and 0 ppm or more and 3 ppm or less of a basic compound.