Abstract: Provided are a process cartridge and an electrophotographic apparatus each suppressed in fluctuation in charging potential at the time of its long-term use. The process cartridge includes: an electrophotographic photosensitive member having a surface layer containing a resin and a charge-transporting substance; and a charging member configured to charge the electrophotographic photosensitive member, wherein an average of Martens hardnesses of the surface layer of the electrophotographic photosensitive member measured at a pushing force of 7 mN is 245 N/mm2 or more, and wherein in a core defined by three-dimensional surface texture standards (ISO 25178-2:2012) of the surface of the charging member, an average of Martens hardnesses measured at a pushing force of 0.04 mN is 2 N/mm2 or more and 20 N/mm2 or less, and an average of adhesivenesses measured with a scanning probe microscope in a field of view of 2-micrometer square is 70 mV or less.

Abstract: A process cartridge configured to be detachably attachable to a main body of an electrophotographic image forming apparatus, in which an occurrence of an image failure is suppressed, wherein the process cartridge includes an electrophotographic photosensitive member and a cleaning member arranged in contact with the electrophotographic photosensitive member, wherein an elastic deformation modulus of a surface layer of the electrophotographic photosensitive member is 35% or larger, and the cleaning member is formed of a urethane foam, wherein a density of the urethane foam is 200 to 500 kg/cm3, and a 25% compressive load of the urethane foam is 0.3 MPa or smaller.

Abstract: An electrophotographic photosensitive member includes a surface layer containing a charge transporting material and a polyester resin having a specific structure.

Abstract: A process cartridge configured to be detachably attachable to a main body of an electrophotographic image forming apparatus, in which an occurrence of an image failure is suppressed, wherein the process cartridge includes an electrophotographic photosensitive member and a cleaning member arranged in contact with the electrophotographic photosensitive member, wherein an elastic deformation modulus of a surface layer of the electrophotographic photosensitive member is 35% or larger, and the cleaning member is formed of a urethane foam, wherein a density of the urethane foam is 200 to 500 kg/cm3, and a 25% compressive load of the urethane foam is 0.3 MPa or smaller.

Abstract: Provided is a process cartridge having a charging member and an electrophotographic photosensitive member to be charged by being in contact with the charging member, wherein the electrophotographic photosensitive member has a support and a photosensitive layer in this order, and a surface layer of the electrophotographic photosensitive member has a Martens hardness of 230 N/mm2 or less.

Abstract: Provided are a process cartridge and an electrophotographic apparatus each suppressed in fluctuation in charging potential at the time of its long-term use. The process cartridge includes: an electrophotographic photosensitive member having a surface layer containing a resin and a charge-transporting substance; and a charging member configured to charge the electrophotographic photosensitive member, wherein an average of Martens hardnesses of the surface layer of the electrophotographic photosensitive member measured at a pushing force of 7 mN is 245 N/mm2 or more, and wherein in a core defined by three-dimensional surface texture standards (ISO 25178-2:2012) of the surface of the charging member, an average of Martens hardnesses measured at a pushing force of 0.04 mN is 2 N/mm2 or more and 20 N/mm2 or less, and an average of adhesivenesses measured with a scanning probe microscope in a field of view of 2-micrometer square is 70 mV or less.

Abstract: An electrophotographic photoreceptor abuts against a charging member and/or a developer carrying member with an abutting member therebetween, has a first portion and a second portion abutting against the abutting member along the longitudinal direction of the photoreceptor, and includes a support, a charge generating layer containing a charge generation material, and a surface layer in this order. The first portion includes an undercoat layer containing a polymer of a composition containing an electron transport material and a crosslinking agent and being contiguous with the surface of the charge generating layer facing the support. The second portion includes (i) an intermediate layer being disposed between and being contiguous with the support and the charge generating layer and/or (ii) an intermediate layer being disposed between and being contiguous with the charge generating layer and the surface layer, wherein the intermediate layers each have a Martens hardness of 500 N/mm2 or less.

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.

Abstract: An electrophotographic photosensitive member including a surface layer containing a specific polyester resin is provided. The polyester resin contains specific structures.

Abstract: A battery includes: an electrode body; and a battery can configured to accommodate the electrode body and include a bottom part. At least one surface of the bottom part has two or more grooves on a same circumference, a proportion of an inner diameter of the groove to an outer diameter of the bottom part is 44% or more, and a proportion of a total value of intervals of the grooves to a perimeter of the circumference is 2% or more and 24% or less.

Abstract: An electrophotographic photosensitive member includes a surface layer containing a charge transporting material and a polyester resin having a specific structure.

Abstract: An electrophotographic photosensitive member including a surface layer containing a charge generating material and a polyester resin is provided. The polyester resin contains a structure having a 12- or higher-membered cycloalkylene 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.

Abstract: A support, a conductive layer, and an intermediate layer of an electrophotographic photosensitive member have a particular surface profile. The intermediate layer is a cured film containing particles.

Abstract: An image forming method in which a surface layer of an electrophotographic photosensitive member contains a compound having a specific structure in an amount of 0.1% to 10% by mass based on the total mass of the surface layer, and in a charged region of the surface of the electrophotographic photosensitive member charged in a charging step, a non-image forming region in which an electrostatic latent image is not formed is not irradiated with destaticizing light or is irradiated with reduced destaticizing light.

Abstract: A secondary battery capable of obtaining superior cycle characteristics and superior swollenness characteristics is provided. The secondary battery includes a cathode and an anode capable of inserting and extracting an electrode reactant; and an electrolyte containing a solvent and an electrolyte salt. The anode has an anode active material layer on an anode current collector. The anode active material layer contains a plurality of crystalline anode active material particles having silicon (Si) as an element. The plurality of anode active material particles contain a spherical particle and a nonspherical particle.

Abstract: A secondary battery capable of improving the cycle characteristics and the initial charge and discharge characteristics is provided. The secondary battery includes a cathode, an anode, and an electrolytic solution. The anode has an anode active material layer on an anode current collector. The anode active material layer contains a crystalline anode active material having silicon as an element, and is linked to the anode current collector.

Abstract: An electrophotographic photosensitive member including a surface layer containing a specific polyester resin is provided. The polyester resin contains specific structures.

Abstract: An electrophotographic photosensitive member including a surface layer containing a charge generating material and a polyester resin is provided. The polyester resin contains a structure having a 12- or higher-membered cycloalkylene group.

Abstract: An electrophotographic photosensitive member comprises a support, an undercoat layer, a charge generation layer and a hole transporting layer disposed in this order. The undercoat layer contains silica particles and a polymer of a composition including an electron transporting material having a polar group selected from the group consisting of a hydroxy group, a thiol group, an amino group, a carboxy group and a methoxy group, and a cross-linking agent. The content of the electron transporting material in the composition is 30 to 70 mass % relative to the total mass of the composition and the content of the silica particles in the undercoat layer is 1 to 30 mass % relative to the total mass of the electron transporting material.