Abstract: An electrophotographic apparatus having an electrophotographic photosensitive member, a charging unit, and a developing unit for forming a toner image, wherein the charging unit has a conductive member disposed to be contactable with the electrophotographic photosensitive member, a conductive layer at the surface of the conductive member has a matrix-domain structure, at least a portion of the domains is exposed at the outer surface of the conductive member, the outer surface of the conductive member is constituted at least of the matrix and these domains, a volume resistivity R1 of the matrix is greater than 1.00×1012 ?·cm, a volume resistivity R2 of the domains is less than R1, Martens hardness G1 of the matrix and Martens hardness G2 of the domains satisfy a prescribed relationship, and an onset temperature T(A) for a storage elastic modulus E? of the toner is not more than 80.0° C.
Type:
Grant
Filed:
October 15, 2020
Date of Patent:
September 20, 2022
Assignee:
CANON KABUSHIKI KAISHA
Inventors:
Tomohiro Unno, Kosuke Fukudome, Dai Nozaki, Kozue Uratani, Yuta Komiya, Kazuhiro Yamauchi, Masahiro Kurachi
Abstract: A method for ascertaining the concentration of at least one material in a powder mixture used as starting material for the production of a component in an additive production method, comprising: providing the powder mixture having at least two different materials; guiding a high-energy beam generated by a radiation source over the surface of the powder mixture; detecting by a detection unit at least one brightness value of at least one subregion of the surface irradiated by the high-energy beam during the irradiation; ascertaining by an analysis unit the concentration of at least one material in the powder mixture depending on the detected at least one brightness value and at least one predetermined reference brightness value for a concentration and/or a concentration range of the material.
Type:
Grant
Filed:
January 11, 2017
Date of Patent:
August 16, 2022
Assignee:
MTU AERO ENGINES AG
Inventors:
Alexander Ladewig, Andreas Jakimov, Katrin Friedberger
Abstract: There is provided an electrophotographic photoreceptor obtained by sequentially laminating at least a photosensitive layer and an outermost layer on a conductive support, wherein the outermost layer contains a polymerized and cured product of a composition containing a polymerizable monomer and a filler, and the filler includes a conductive first filler surface-treated with a surface treatment agent having a silicone chain in a side chain, and a second filler having a relative dielectric constant which is lower than that of the first filler and 5 or less.
Abstract: An electrophotographic photoreceptor includes: a conductive base body and a photosensitive layer, in which an outermost surface layer of the electrophotographic photoreceptor contains fluorine-containing resin particles, and in which a fluorine atom concentration at a surface of the outermost surface layer is 1.5 to 5.0 times a fluorine atom concentration at a depth of 1 ?m from the surface of the outermost surface layer, or in which a number density ratio of aggregates of the fluorine-containing resin particles in a second region defined in this specification, to aggregates of he fluorine-containing resin particles in a first region defined in this specification is less than 0.95, and a ratio of an area ratio of the fluorine-containing resin particles in the second region, to an area ratio of the flourine-containing resin particles in the first region is within a range of 1±0.1.
Abstract: To provide a liquid composition whereby a resin powder can be uniformly dispersed in a resin or the like without being scattered, and a method for producing a film, a laminate or the like by using the liquid composition. The liquid composition comprises a liquid medium and a resin powder dispersed in the liquid medium, and characterized in that the average particle size of the resin powder is from 0.3 to 6 ?m, the volume-based cumulative 90% diameter of the resin powder is at most 8 ?m, and the resin powder is a resin containing a fluorinated copolymer having a specific functional group. And, the method is a method for producing a film, a laminate or the like by using the liquid composition.
Abstract: An electrophotographic photoreceptor includes a conductive substrate; an undercoat layer that is disposed on the conductive substrate and contains metal titanate compound particles, an electron transporting compound, and a binder resin; and a photosensitive layer on the undercoat layer.
Type:
Grant
Filed:
July 24, 2019
Date of Patent:
October 19, 2021
Assignee:
FUJIFILM Business Innovation Corp.
Inventors:
Kota Maki, Masahiro Iwasaki, Kenji Kajiwara
Abstract: A dispersant-attached polytetrafluoroethylene particle includes a polytetrafluoroethylene particle and a dispersant that attaches to a surface of the polytetrafluoroethylene particle and contains a fluorine atom. The particle size distribution index [D50-D10] is less than 50 nm and the electrical conductivity is 7 ?S/cm or less.
Abstract: Provided is an electrophotographic photosensitive member in which discharge streaks generated in an end portion can be suppressed. The electrophotographic photosensitive member includes a cylindrical support, a charge-generating layer, and a charge-transporting layer in the stated order. In the electrophotographic photosensitive member, when a region between a center position and a 90% position situated at a 90% of a length of from the center position to one end of the electrophotographic photosensitive member in an axial direction thereof from the center position, is defined as a region X, and a region between the 90% position and the end of the electrophotographic photosensitive member is defined as a region Z. Average thicknesses in regions obtained by equally dividing the region X into five and regions obtained by equally dividing the region Z into three satisfy particular relationships.
Abstract: The electrophotographic photosensitive member includes: a support; a charge-generating layer; and a charge-transporting layer, the charge-generating layer and the charge-transporting layer being arranged on the support, wherein a surface layer of the electrophotographic photosensitive member contains: inorganic particles having an average particle diameter (L?) of primary particles of 5 nm or more and 50 nm or less; and resin particles having an average particle diameter (L?) of primary particles of 0.1 ?m or more and 5.0 ?m or less, and wherein in any cross-section of the surface layer, “(Sm?)/(S?)?0.3” is satisfied, where a region within (L?/2) from a surface of each of the resin particles is defined as a region (M), a sum of cross-sectional areas of the inorganic particles in the any cross-section is represented by (S?), and a sum of cross-sectional areas of the inorganic particles that are included in the region (M) is represented by (Sm?).
Type:
Grant
Filed:
January 17, 2020
Date of Patent:
September 7, 2021
Assignee:
CANON KABUSHIKI KAISHA
Inventors:
Koji Takahashi, Akifumi Matsubara, Yuya Chimoto
Abstract: An electrophotographic photoreceptor includes a support, an undercoat layer placed on the support, a charge generation layer placed on the undercoat layer, and a charge transport layer placed on the charge generation layer. The undercoat layer contains titanium oxide particles surface-treated with an organosilicon compound that is at least one member selected from the group consisting of compounds represented by formulas (1) to (8) and a polyamide resin. The charge generation layer contains hydroxygallium phthalocyanine.
Abstract: A dispersant-attached polytetrafluoroethylene particle includes a polytetrafluoroethylene particle; and a dispersant that contains a fluorine atom and is attached to a surface of the polytetrafluoroethylene particle. The dispersant-attached polytetrafluoroethylene particle has a particle size distribution index [D50-D10] of 50 nm or more.
Abstract: An electrophotographic photoreceptor includes a support, a photosensitive layer, and a protection layer. The protection layer contains a copolymer of a compound having a specific frame and a hole-transporting compound containing a specific polarizable functional group.
Abstract: Disclosed in certain embodiments is an electron donor for a polyolefin polymerization catalyst. In some embodiments, a solid catalyst component includes a metal component and the electron donor that form a catalyst on a support.
Type:
Grant
Filed:
August 11, 2016
Date of Patent:
May 11, 2021
Assignee:
BRASKEM AMERICA, INC.
Inventors:
Binh Thanh Nguyen, Jonas Alves Fernandes
Abstract: 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 ?m 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.
Abstract: A process cartridge includes a developing device that supplies developer to a photosensitive member and an elastic portion that cleans a peripheral surface of the photosensitive member. Multiple grooves are formed side by side in a generatrix direction on the peripheral surface. The developer contains a toner including a toner particle and an organosilicon polymer having a structure represented by R—SiO3/2 covering the toner particle surface, where R represents a hydrocarbon group having at least 1 and not more than 6 carbon atoms. When a penetration amount of the elastic portion with respect to the photosensitive member is set as ? (mm), and a fixing rate of the organosilicon polymer on the surface of the toner particle is set as ? (%), ??0.02×??0.4 is satisfied.
Abstract: 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/mm2.
Abstract: A bis-butadiene derivative is represented by general formula (1) shown below. 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.
Abstract: Provided are an electrophotographic photosensitive member including a support and a photosensitive layer above the support, in which a surface layer of the electrophotographic photosensitive member includes a polymerization product of a composition containing a specific hole transporting compound, and an electrophotographic apparatus and a process cartridge including the electrophotographic photosensitive member. Also provided is a method of producing the electrophotographic photosensitive member, including (i) forming a coating film of a coating solution for a surface layer which is a composition containing a specific hole transporting compound, and (ii) forming the surface layer of the electrophotographic photosensitive member by a polymerization reaction of the composition containing the specific hole transporting compound.
Abstract: Subject matter herein disclosed relates to a method for the manufacture of a CEM switching device providing that the CEM layer comprises a doped metal compound substantially free from metal wherein ions of the same metal element are present in different oxidation states. The method may provide a CEM layer which is born on and capable of switching with operating voltages below 2.0V.
Type:
Grant
Filed:
October 24, 2018
Date of Patent:
May 19, 2020
Assignee:
Arm Limited
Inventors:
Kimberly Gay Reid, Lucian Shifren, Carlos Alberto Paz de Araujo, Jolanta Bozena Celinska
Abstract: The present disclosure relates to an electrophotographic photoreceptor which can suppress occurrence of abnormalities such as peeling or falling off of a film from a substrate end portion in a film formation step of a surface layer and maintain and reproduce a stable printing quality even in a use stage after productization, and an image forming apparatus including the same. An electrophotographic photoreceptor includes a cylindrical substrate including a chamfered face located between an substrate outer circumferential surface and a substrate end face, and a surface layer located on the outer circumferential surface. The substrate outer circumferential surface includes a first uneven portion. The chamfered face includes a second uneven portion and a third uneven portion located on a surface of the second uneven portion. A surface roughness Sa of the second uneven portion is larger than a surface roughness Sa of the third uneven portion.
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 electrophotographic photosensitive member includes a support and a surface layer, in which the surface layer contains a copolymer of a composition which contains at least a compound represented by the following general formula (1) and a compound represented by the following general formula (2), a content of the compound represented by the general formula (1) in the composition is 25 mass % or more and 70 mass % or less with respect to a total content of the compound represented by the general formula (1) and the compound represented by the general formula (2), and the total content of the compound represented by the general formula (1) and the compound represented by the general formula (2) is 55 mass % or more with respect to a total mass of the composition.
Abstract: An electrophotographic photosensitive member suppressing potential variation due to repeated use is provided. The electrophotographic photosensitive member is an electrophotographic photosensitive member including a support, a photosensitive layer and a protective layer in this order, wherein the protective layer contains: a resin including a structure represented by a general formula (1) and a structure represented by a general formula (2); and a compound represented by a general formula (3), the molar ratio of the proportion of the structure represented by the general formula (2) to the proportion of the structure represented by the general formula (1) in the resin is 0.0002 to 0.1000 in a molar ratio, and the molar ratio of the content of the compound represented by the general formula (3) to the content of the structure represented by the general formula (1) in the resin in the protective layer is 0.0002 to 0.1000 in a molar ratio.
Abstract: A method of producing an electrophotographic photoreceptor composed of a photosensitive layer provided on a conductive substrate, includes, in the formation of an outermost layer, controlling slope k of a straight line obtained by plotting the average film density of outermost layer and boiling point of solvent used for the formation of the outermost layer along the ordinate and the abscissa, respectively, to be 1.50E-4 (g/cm3·° C.) or greater, and adjusting the difference in film density of the outermost layer between the surface side and the side close to the conductive substrate to be 0.030 g/cm3 or less. The electrophotographic photoreceptor has reduced image defects even after long-term use and has excellent wear performance.
Abstract: There is provided an electrophotographic member which suppresses scraping and contamination of a surface even in the durable use of multiple sheet printing under a high temperature environment. The electrophotographic member has an electroconductive substrate and a single elastic layer as a surface layer, the surface layer includes a binder resin and carbon black dispersed in the binder resin, the carbon black has a volatile content of 0.4% or more, the binder resin includes a crosslinked urethane resin and a crosslinked acrylic resin, and the surface layer has a first area in which the crosslinked urethane resin and the crosslinked acrylic resin form an interpenetrating polymer network structure, the first area being from an outer surface of the surface layer to a depth of 0.1 ?m in the surface layer.
Abstract: Provided is an electrophotographic photosensitive member that is reduced in exposure memory and is excellent in electrical characteristics and durability. The electrophotographic photosensitive member includes in this order: a support; a photosensitive layer; and a protective layer, wherein the protective layer contains a resin having a structure represented by the following general formula (1) and a structure represented by the following general formula (2).
Abstract: 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 hole transport material, an electron transport material, and a binder resin. An optical response time is at least 0.05 milliseconds and no greater than 0.85 milliseconds. The binder resin includes a polycarbonate resin including a repeating unit represented by general formula (1) shown below and a repeating unit represented by general formula (2) shown below.
Abstract: There is provided an electrophotographic photosensitive member, a process cartridge and an electrophotographic apparatus in which residual potential is suppressed and a ghost image is prevented from being generated in a low-humidity environment in an undercoat layer of the electrophotographic photosensitive member. An electrophotographic photosensitive member including: an undercoat layer containing a strontium titanate particle having a maximum peak at a position of 2?=32.20±0.20 (? represents a Bragg angle) in a CuK? characteristic X-ray diffraction pattern and a half-value width of the maximum peak of 0.10 deg or more and 0.50 deg or less, and a titanium oxide particle; and a photosensitive layer containing a polyvinyl butyral resin, and a process cartridge and an electrophotographic apparatus each provided with the electrophotographic photosensitive member.
Abstract: A surface layer of an electrophotographic photosensitive member contains a cured product of a composition containing a hole transport compound having an acryloyloxy group or a methacryloyloxy group, and a compound having a specific structure.
Abstract: The present invention relates to a solid lubricant to be coated on an image bearing member included in an electrophotographic image forming apparatus. The solid lubricant contains a resin particle and metal soap. The resin particle includes a particle body containing an amorphous resin as a principal component, and a fluorine atom supported on a surface of the particle body. The resin particle is a particle having a volume average particle size of 70 nm or more. The solid lubricant can sufficiently increase a cleaning effect in the image forming apparatus.
Abstract: A coating film of a coating liquid for a surface layer, the coating liquid containing a hole transporting compound having a chain-polymerizable functional group and a compound having a specified structure, is cured to thereby form a surface layer of an electrophotographic photosensitive member.
Abstract: An electrophotographic photoconductor comprises a support, an undercoat layer, a charge generation layer, and a hole transport layer in this order. The undercoat layer comprises an electron transport substance, and the charge generation layer comprises a gallium phthalocyanine crystal and an amide compound represented by formula (N1): where R1 represents a methyl group, a propyl group, or a vinyl group.
Abstract: A light-emitting device includes an emissive layer that emits light by recombination of first charges and second charges; a first electrode from which the first charges are supplied; a second electrode from which the second charges are supplied; a first charge transport layer that injects the first charges from the first electrode into the emissive layer; and a second charge transport layer that injects the second charges from the second electrode into the emissive layer. At least one of the charge transport layers is an absorbing charge transport layer that includes a light absorbing material that absorbs light within a portion of the emission spectrum of the light emitted by the emissive layer. The absorbing charge transport layer may be an ETL or an HTL, and may be located only between the first electrode and the emissive layer, only between the opposing second electrode and the emissive layer, or between both electrodes and the emissive layer.
Type:
Grant
Filed:
March 28, 2018
Date of Patent:
July 30, 2019
Assignee:
Sharp Kabushiki Kaisha
Inventors:
Edward Andrew Boardman, James Andrew Robert Palles-Dimmock, Enrico Angioni, Tim Michael Smeeton
Abstract: The present invention provides an electrophotographic member which has a high ability to impart charge to toners while the charge imparting ability is unlikely to be reduced even under an environment at high temperature and high humidity. The electrophotographic member comprises a substrate, an elastic layer formed on the substrate, an intermediate layer covering the surface of the elastic layer, and a surface layer covering the surface of the intermediate layer, wherein the intermediate layer contains a binder resin and a polymer having a specific structure, the surface layer contains silicon oxide, and the surface layer has a thickness of 10 nm or more and 300 nm or less.
Abstract: Provided is an electrophotographic photoreceptor obtained by laminating a photosensitive layer and a surface protective layer in this order on a conductive support, wherein the surface protective layer contains conductive fine particles and crosslinkable organic fine particles, and either the conductive fine particles or the crosslinkable organic fine particles have been subjected to surface modification with a fluoroalkyl (meth)acrylate/(meth)acrylic acid copolymer.
Abstract: Provided are an electrophotographic photosensitive member capable of satisfying abrasion resistance and electrical properties and suppressing image deletion, and an electrophotographic apparatus and a process cartridge having the electrophotographic photosensitive member. A surface layer of the electrophotographic photosensitive member contains a polymer of a hole transport material having a polymerizable functional group, wherein the hole transport material has a specific structure.
Abstract: A polyarylate resin is represented by general formula (1) shown below. In general formula (1), R1 and R2 each represent, independently of one another, a hydrogen atom or a methyl group. r and s each represent an integer of at least 0 and no greater than 49. t and u each represent an integer of at least 1 and no greater than 50. r+s+t+u=100. r+t=s+u. X and Y each represent, independently of one another, a divalent group represented by chemical formula (1-1), chemical formula (1-2), chemical formula (1-3), or chemical formula (1-4). X and Y are different from one another.
Abstract: An electrophotographic photosensitive member includes a support member, an electroconductive layer, and a photosensitive layer in this order. The electroconductive layer contains a binder and particles. Each of the particles include a core made of a substance represented by general formula (1), and a coating layer coating the core and containing an electrically conductive material: M1M2O3??(1) wherein M1 represents an element selected from the group consisting of Sr, Li, Na, K, and Ba, and M2 represents an element selected from the group consisting of Ti, Nb, Ta, and Zr.
Abstract: An electrophotographic photosensitive member includes a conductive substrate and a photosensitive layer. The photosensitive layer has a single-layer structure and contains a charge generating material and a compound represented by general formula (1) shown below. In the general formula (1), R1 and R2 each represent, independently of each other: an alkyl group having 1 to 12 carbon atoms and optionally substituted by an alkoxy group having 1 to 6 carbon atoms or an alkoxycarbonyl group having 2 to 6 carbon atoms; an aryl group having 6 to 14 carbon atoms and optionally substituted by an alkyl group having 1 to 6 carbon atoms; an aralkyl group having 7 to 20 carbon atoms; or a cycloalkyl group having 3 to 10 carbon atoms. X represents —S— or —SO2—.
Abstract: An electrophotographic photoconductor including a support, an undercoat layer, and a photoconductive layer, the undercoat layer and the photoconductive layer being disposed on the support in an order mentioned, wherein the undercoat layer includes zinc oxide particles, a urethane bond-containing resin, and methylethyl ketone oxime, and the undercoat layer satisfies a formula below: 10<M/L<400??(Formula) where M is a ratio (ppm) of the methylethyl ketone oxime included in the undercoat layer, and L is an average thickness (?m) of the undercoat layer.
Abstract: A quinone derivative is represented by general formula (1). In general formula (1), at least one of R1-R3 and at least one of R4-R6 each represent, independently of one another, an alkyl group having 4 to 10 carbon atoms or an alkyl group having 2 to 5 carbon atoms that has an aryl group having 6 to 14 carbon atoms. All other of R1-R3 and all other of R4-R6 each represent, independently of one another, an alkyl group having 1 to 6 carbon atoms, an aryl group having 6 to 14 carbon atoms, or a cycloalkyl group having 3 to 10 carbon atoms.
Abstract: An electrophotographic photosensitive member includes a support member, an electroconductive layer, and photosensitive layer in this order. The electroconductive layer contains a binder and particles. The particles have a core containing titanium oxide, and a coating layer coating the core and containing titanium oxide doped with niobium or tantalum.
Abstract: The present invention discloses a composite catalyst for the photocatalytic isomerization of norbornadiene to prepare quadricyclane, comprising: a solid photocatalyst, selected from the group consisting of TiO2, Ti-MCM-41, Ti-SBA-15, ZnO, WO3, Ta2O5 or SrTiO3; and an organic photo-sensitizer loaded on the surface or in the channel of said solid photocatalyst, selected from benzophenone, acetophenone, Michler's Ketone, tetraethyl Michler's Ketone, and diethyl Michler's Ketone, where the organic photo-sensitizer is present in the solid photocatalyst in an amount of 0.5% to 20% by weight. The catalyst of the invention can catalyze a target reaction under the condition that no solvent is used, and the yield of the target product quadricyclane is higher. Furthermore, the catalyst of the invention has a stable activity, and it can be recycled. The invention further discloses a process for preparing the composite catalyst.
Type:
Grant
Filed:
May 23, 2014
Date of Patent:
November 27, 2018
Assignee:
TIANJIN UNIVERSITY
Inventors:
Jijun Zou, Xiangwen Zhang, Li Wang, Qingfa Wang
Abstract: The present invention is to provide a charge transport substance having high resistance to stress within electrophotographic processes, an electrophotographic photoreceptor which has excellent high-speed responsiveness, shows a sufficient residual potential, and has high resistance to stress within electrophotographic processes, an electrophotographic cartridge, and an image-forming apparatus. The invention provides a charge transport substance having a specific structure. The invention further provides an electrophotographic photoreceptor including a photosensitive layer which contains the charge transport substance having a specific structure, an electrophotographic cartridge, and an image-forming apparatus, equipped with this electrophotographic photoreceptor.
Abstract: The present teachings relate to hybrid organic-inorganic perovskite solar cells including a hole-transport layer in contact with the perovskite light-absorbing layer, where the hole-transport layer (HTL) is a pristine (undoped) polymer. More specifically, the HTL comprises a copolymer including a benzo[1,2-d;4,5-d?]bistriazole-containing repeating unit and a benzo[1,2-b:4,5-b?]dithiophene-containing repeating unit.
Type:
Grant
Filed:
May 18, 2016
Date of Patent:
October 30, 2018
Assignee:
Northwestern University
Inventors:
Tobin J. Marks, Robert P. H. Chang, Teck Lip Dexter Tam, Hsueh-Chung Liao, Antonio Facchetti
Abstract: An electrophotographic photoreceptor includes a conductive substrate and a photosensitive layer disposed on the conductive substrate, wherein when time that takes for a current value to reach the maximum after beginning of application of a square wave voltage to the electrophotographic photoreceptor is T1 and time that takes for the current value to reach the maximum after the beginning of the application of the square wave voltage and then decrease to one fifth of the maximum is T2, T2 is approximately from 3.2 to 11.0 times as large as T1.
Abstract: Electrophotographic photoreceptor including a conductive substrate, an organic photosensitive layer on an outer peripheral surface of the conductive substrate, and an inorganic protective layer on an outer peripheral surface of the organic photosensitive layer, the inorganic protective layer containing gallium and oxygen. A volume resistivity of an inner region of the inorganic protective layer, the inner region extending 0.2 ?m or about 0.2 ?m from an inner peripheral surface of the inorganic protective layer in a thickness direction, and a volume resistivity of an outer region of the inorganic protective layer, the outer region extending 0.2 ?m or about 0.2 ?m from an outer peripheral surface of the inorganic protective layer in the thickness direction, are both 6.0×107 ?·cm or more and 4.0×108 ?·cm or less or about 6.0×107 ?·cm or more and about 4.0×108 ?·cm or less.
Abstract: 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.
Abstract: An electrophotographic photosensitive member includes a surface layer containing a charge transporting material and a specific polyester resin having a structure including a specific branched chain.