Abstract: An image-forming apparatus with strontium titanate used as an external additive for a toner is provided, wherein the image-forming apparatus is an electrophotographic apparatus that has the durability of an electrophotographic photosensitive member maintained and is superior in transferability even under low-temperature/low-humidity conditions. An electrophotographic apparatus is provided, the electrophotographic apparatus including: an electrophotographic photosensitive member having a surface layer containing a resin X as a binder resin; a charging unit; an exposing unit; a developing unit; and a transferring unit, wherein the toner contains strontium titanate as an external additive, and the resin X contains a structural unit represented by Formula (1).

Abstract: Provided is a process cartridge capable of suppressing the occurrence of a banding image that is detachably attachable onto a main body of an electrophotographic apparatus. A developing roller and a toner supply roller are configured to be rotated so that R represented by the following formula (E1) satisfies 1.2?R?1.5 and are configured so that a movement direction of a surface of the developing roller is opposite to a movement direction of a surface of the toner supply roller at a contact position with respect to the toner supply roller: R=VRS/VD Formula (E1) (in the formula (E1), VRS represents an absolute value of a peripheral speed [m/s] of the toner supply roller, and VD represents an absolute value of a peripheral speed [m/s] of the developing roller). An electrophotographic photosensitive member includes a surface layer containing a polyarylate resin including a structural unit represented by the following formula (A1).

Abstract: Provided is a process cartridge being detachably attachable onto a main body of an electrophotographic apparatus. The process cartridge includes an electrophotographic photosensitive member, a developing roller, and a toner-supplying roller. The developing roller and the toner-supplying roller are rotated so as to satisfy a particular velocity ratio so that the surface of the developing roller and the surface of the toner-supplying roller are opposite to each other at a contact position therebetween. The surface of the developing roller is a surface of an elastic layer, and the toner-supplying roller includes a shaft body and a resin layer formed on an outer peripheral surface of the shaft body. The electrophotographic photosensitive member includes a surface layer containing a polyarylate resin including a structural unit represented by the following formula (A1) and a structural unit represented by the following formula (A2).

Abstract: Provided is a process cartridge being detachably attachable onto a main body of an electrophotographic apparatus. The process cartridge includes an electrophotographic photosensitive member, a developing roller, and a toner-supplying roller. The developing roller and the toner-supplying roller are configured to be opposite to each other at a contact position between the developing roller and the toner-supplying roller, and to be rotated while R represented by the following formula (E1) satisfies 1.2?R?1.5: R=VRS/VD Formula (E1) (in the formula (E1), VRS represents an absolute value of a peripheral velocity [m/s] of the toner-suppling roller, and VD represents an absolute value of a peripheral velocity [m/s] of the developing roller). The electrophotographic photosensitive member includes a surface layer containing a polycarbonate resin including a structural unit represented by the formula (A1).

Abstract: Provided is an electrophotographic photosensitive member including in this order: a support; an undercoat layer, and a photosensitive layer, wherein the undercoat layer comprises at least one kind of polymer selected from the group consisting of: a polymer having a structural unit represented by the following formula (1); and a polymer having a structural unit represented by the following formula (2).

Abstract: Provided is an electrophotographic photosensitive member in which streaky image damage can be suppressed throughout long-term use in a low-temperature and low-humidity environment. An electrophotographic photosensitive member having a surface layer comprising a polyarylate and a polycarbonate, wherein the polyarylate has at least one structural unit selected from the group consisting of a structural unit represented by the following formula (1-1), a structural unit represented by the following formula (1-2) and a structural unit represented by the following formula (1-3), and the polycarbonate has a structural unit represented by the following formula (2-1).

Abstract: An electrophotographic photosensitive member includes a surface layer. The surface layer comprises a polycarbonate resin (?) and a polycarbonate resin (?). The polycarbonate resin (?) has a structural unit represented by a following formula (A) described herein and a structural unit represented by a following formula (B) described herein. The polycarbonate resin (?) has a structure having a dimethylsiloxane moiety.

Abstract: Provided is a process cartridge integrally supporting an electrophotographic photosensitive member, a developing unit, and a cleaning unit, and being detachably attachable onto a main body of an electrophotographic apparatus. A surface layer of the electrophotographic photosensitive member comprises a polycarbonate resin having a structural unit represented by the formula (1), a structural unit represented by the formula (2), and a structural unit represented by the formula (3). Toner contains: a toner particle containing a resin; and an external additive. The external additive contains a particle of a silicon atom-containing compound, and a content ratio of the particle of the silicon atom-containing compound in the toner is 2.0 to 3.0 mass % with respect to a total mass of the toner. Also provided is an electrophotographic apparatus including the process cartridge.

Abstract: To provide an electrophotographic photosensitive member capable of satisfying both high durability and high sensitivity at a high level. An electrophotographic photosensitive member having a support, a charge generation layer formed on the support and a charge transport layer formed on the charge generation layer, the charge transport layer being a surface layer, in which the charge transport layer comprises a polyester resin having a structural unit represented by the following formula (1) and a charge-transporting compound represented by the following formula (HTM1).

Abstract: An object of the present disclosure is to provide an electrophotographic photosensitive member with suppressed positive ghosts, and a process cartridge and an electrophotographic apparatus each including the electrophotographic photosensitive member. The present disclosure provides an electrophotographic photosensitive member having a support and a photosensitive layer on the support; the photosensitive layer comprises (?) a compound represented by the formula (1), and (?) at least one selected from the group consisting of a compound represented by the formula (2) and a compound represented by the formula (3), wherein a content of the (?) with respect to a content of the (?) is 50 to 850 mass ppm in the photosensitive layer.

Abstract: The electrophotographic photosensitive member includes a surface layer containing a binder resin, electroconductive particles, and insulating particles, wherein when a volume resistivity of the insulating particles is represented by R1 [?·cm], a volume resistivity of the electroconductive particles is represented by R2 [?·cm], a ratio of an area of the insulating particles that are exposed to a total area of the surface layer is represented by S1 [%], a ratio of an area of the electroconductive particles that are exposed to the total area of the surface layer is represented by S2 [%], an average exposed height of the insulating particles exposed to a surface of the electrophotographic photosensitive member is represented by L1 [nm], and an average exposed height of the electroconductive particles exposed to the surface of the electrophotographic photosensitive member is represented by L2 [nm], those parameters satisfy specific relational formulae.

Abstract: An electrophotographic photosensitive member including a surface layer containing a binder resin and metal oxide particles. An average primary particle diameter of the metal oxide particles measured from a cross-section of the surface layer is 20 to 70 nm. A content ratio of the metal oxide particles in the surface layer measured from the cross-section of the surface layer is 30 to 75 vol % with respect to a total volume of the surface layer.

Abstract: The process cartridge is a process cartridge to be removably mounted onto a main body of an electrophotographic apparatus, the process cartridge including: an electrophotographic photosensitive member; a toner; and a developing member, wherein the electrophotographic photosensitive member includes a surface layer that is a polymerized film of a composition containing at least one kind of monofunctional (meth)acrylic compound selected from the group consisting of: a monofunctional (meth)acrylic monomer; and a monofunctional (meth)acrylic oligomer, and at least one kind of tri- or higher functional (meth)acrylic compound selected from the group consisting of: a tri- or higher functional (meth)acrylic monomer; and a tri- or higher functional (meth)acrylic oligomer, wherein the toner contains a toner particle and a hydrotalcite particle as an external additive, and wherein the hydrotalcite particle contains fluorine in filter fitting analysis of STEM-EDS analysis.

Abstract: Provided is a process cartridge removably mountable onto a main body of an electrophotographic apparatus, the process cartridge comprising an electrophotographic photosensitive member, a toner, and a developing member configured to supply the toner to the electrophotographic photosensitive member, wherein, in filter fitting analysis in STEM-EDS analysis, a hydrotalcite particle comprises fluorine, and wherein, when a number-average primary particle diameter of a particle A is represented by “m” [nm], a content ratio of the particle A with respect to the surface layer is represented by “p” [vol %], and a number-average primary particle diameter of the hydrotalcite particle is represented by “h” [nm], the “m”, the “p”, and the “h” satisfy the following expressions, respectively: 5?m?300??Expression (1); 5?p?40??Expression (2); and 60?h?1,000??Expression (3).

Abstract: A process cartridge detachably attachable to a main body of an electrophotographic apparatus, the process cartridge including an electrophotographic photosensitive member, a toner, and a developing member that feeds the toner to the electrophotographic photosensitive member, wherein the electrophotographic photosensitive member includes a surface layer containing a (meth)acrylic resin having a urethane structure, the toner includes a toner particle and a hydrotalcite particle as an external additive, and the hydrotalcite particle contains fluorine in filter fitting analysis in STEM-EDS analysis.

Abstract: An electrophotographic photosensitive member that is excellent in image smearing resistance and low torque while maintaining its electrophotographic characteristic. The electrophotographic photosensitive member is an electrophotographic photosensitive member including, in this order: a support; a photosensitive layer; and a protection layer as a surface layer, wherein the protection layer has a surface having a developed area ratio Sdr of 1.0% to 40.0%, and wherein an A value represented by the following formula (1) is 0.10 to 0.27: A=S1/S2 . . . formula (1), where, in the formula (1), S1 represents a peak area based on C?C stretching vibration of an aromatic ring by attenuated total reflection Fourier transform infrared spectroscopy, and S2 represents a peak area based on C?O stretching vibration of an ester group by the same method.

Abstract: An electrophotographic image forming apparatus in which streak-like banding to be formed in an electrophotographic photosensitive member is suppressed. The electrophotographic image forming apparatus includes an electrophotographic photosensitive member, which has a protective layer, and a developer carrying member for supplying a developer. The protective layer contains a cured product containing an aromatic ring and an ester group, by attenuated total reflection Fourier transform infrared spectroscopy, when a peak area based on C?C stretching vibration of the aromatic ring is represented by S1, and a peak area based on C?O stretching vibration of the ester group is represented by S2, an area ratio S1/S2 is 0.10 to 0.27, and a rotation speed ratio D1/D2 of a rotation speed D1 of the developer carrying member to a rotation speed D2 of the electrophotographic photosensitive member is 0.80 to 1.20.

Abstract: 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.

Abstract: 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.

Abstract: An electrophotographic image forming apparatus in which streak-like banding to be formed in an electrophotographic photosensitive member is suppressed. The electrophotographic image forming apparatus comprises an electrophotographic photosensitive member, which has a protective layer, and a developer carrying member for supplying a developer. The protective layer contains a cured product containing an aromatic ring and an ester group, by attenuated total reflection Fourier transform infrared spectroscopy, when a peak area based on C?C stretching vibration of the aromatic ring is represented by S1, and a peak area based on C?O stretching vibration of the ester group is represented by S2, an area ratio S1/S2 is 0.10 to 0.27, and a rotation speed ratio D1/D2 of a rotation speed D1 of the developer carrying member to a rotation speed D2 of the electrophotographic photosensitive member is 0.80 to 1.20.