Abstract: The electrophotographic photosensitive member includes a support and a photosensitive layer on the support, in which a surface layer of the electrophotographic photosensitive member contains a particle, the surface layer has a particle partially exposed from the surface layer among the particle contained in the surface layer, the particle has a volume average particle diameter of 50.0 nm or more and 350.0 nm or less; in a cross-section of the surface layer, the number of the particle partially exposed from the surface layer is 80% by number or more based on a total number of the particle contained in the surface layer; and a total volume of an exposed portion of the particle partially exposed from the surface layer is 30% by volume or more and 80% by volume or less based on an entire volume of the particle contained in the surface layer.

Abstract: Provided is an electrophotographic photosensitive member that achieves satisfactory transferability. An electrophotographic photosensitive member including a charge generating layer, a charge transporting layer, and a protection layer laminated on a support in the stated order, wherein the protection layer contains a binder resin and particles, and wherein when an average thickness of the protection layer in a site free of the particles is represented by T and a volume-average particle diameter of the particles is represented by Dm in a cross-section of the protection layer, the following formula (a) is satisfied.

Abstract: In order to provide a photoelectric conversion element having higher photoelectric conversion efficiency, in a photoelectric conversion element having a first electrode, a second electrode, and a photoelectric conversion layer containing an organic-inorganic perovskite compound and disposed between the first electrode and the second electrode, a particle layer including particles that mainly contain a phthalocyanine compound is arranged between the photoelectric conversion layer and the first electrode.

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: A toner is provided, which has a toner particle that contains a binder resin, and organosilicon polymer particle on a surface of the toner particle. A methanol concentration a (vol %) of the organosilicon polymer particle in a wettability test and a methanol concentration b (vol %) of the toner particle in a wettability test satisfy Expression (I) below: |a?b|?25??(I), and an adhesion index of the organosilicon polymer particle on a polycarbonate film, calculated on the basis of Expression (II) below, is not more than 3.5: Adhesion index=area ratio c of the organosilicon polymer particle having migrated to the polycarbonate film/coverage ratio d of the organosilicon polymer particle on the surface of the toner particle×100??(II).

Abstract: A magnetic toner comprising a magnetic toner particle including a binder resin, a magnetic body and a crystalline polyester, wherein in cross-sectional observation of the magnetic toner particle using a transmission electron microscope, a variation coefficient CV3 of an occupied area ratio of the magnetic body when a cross section of the magnetic toner particle is divided by a square grid having a side of 0.8 ?m is from 40.0% to 80.0%, and assuming that a storage elastic modulus at 40° C. is taken as E?(40) [Pa] and a storage elastic modulus at 85° C. is taken as E?(85) [Pa], the storage elastic moduli being obtained in a powder dynamic viscoelasticity measurement of the magnetic toner, the following formulas (1) and (2) are satisfied. E?(85)?2.

Abstract: There is provided an electrophotographic photosensitive member comprising: a support, a photosensitive layer, and a surface layer in this order, wherein an outer surface of the electrophotographic photosensitive member exhibits a wrinkled shape by having a concavo-convex shape, the surface layer comprises a binder resin and an inorganic particle, and at least a part of the inorganic particle exposes at a concave portion of the concavo-convex shape.

Abstract: Provided is an electrophotographic photosensitive member including an electroconductive support, a photosensitive layer, and a protection layer, wherein the protection layer comprises an electroconductive particle, the electroconductive particle has a surface comprising a metal oxide containing a titanium atom and a niobium atom, an atomic concentration ratio of the niobium atom to the titanium atom in the metal oxide is 0.01 to 0.20, the electroconductive particle is surface-treated with a compound having a silicon atom, a content ratio of the electroconductive particle in the protection layer is 5 vol % or more and less than 40 vol % with respect to a total volume of the protection layer, and relative concentrations of a plurality of atoms at a surface of the protection layer, which are determined by X-ray photoelectron spectroscopy, satisfy specific conditions.

Abstract: A process cartridge including: an electrophotographic photosensitive member having a drum shape; a developing unit for developing an electrostatic latent image on the surface of the electrophotographic photosensitive member with toner; and a cleaning blade for removing the toner on the surface of the electrophotographic photosensitive member, the cleaning blade being in contact with the electrophotographic photosensitive member, wherein the electrophotographic photosensitive member comprises wrinkles on the surface of the electrophotographic photosensitive member, and wherein the toner has a fluidity torque E of 320 mJ or more.

Abstract: The present disclosure provides a photoelectric conversion element including a first electrode 3, a second electrode 7, a photoelectric conversion layer 5 between the first electrode 3 and the second electrode 7, and a reflection layer 6 between one of the first electrode 3 and the second electrode 7 and the photoelectric conversion layer 5. The wavelength at which the reflectance of the reflection layer 6 is maximum in the visible region is within the range of wavelengths in which the optical absorption coefficient of the photoelectric conversion layer 5 is ? or more of the maximum optical absorption coefficient in the visible region.

Abstract: A process cartridge including: an electrophotographic photosensitive member having a drum shape; a developing unit for developing an electrostatic latent image on the surface of the electrophotographic photosensitive member with toner; and a cleaning blade for removing the toner on the surface of the electrophotographic photosensitive member, the cleaning blade being in contact with the electrophotographic photosensitive member, wherein the electrophotographic photosensitive member comprises wrinkles on the surface of the electrophotographic photosensitive member, and wherein the toner has a fluidity torque E of 320 mJ or more.

Abstract: In an electrophotographic photosensitive member, wrinkles have a convex portion in which a linear shape portion having a length of 50 ?m or longer exists, the linear shape portion is parallel to any one of L1 to L150 and L1651 to L1800, and each of L1 to L1800 intersects with the convex portion at a plurality of places, and at least two of the places have different intersection angles; and when height information of the wrinkles is subjected to a frequency analysis, and a two-dimensional power spectrum is obtained, a one-dimensional radial distribution function has at least one local maximum value, and when an angular distribution is calculated from the spectrum at a frequency of the local maximum value, the power values have a particular relationship.

Abstract: A toner comprising a resin that contains an amorphous segment and a crystalline segment as a binder resin, wherein a proportion of a tetrahydrofuran-insoluble matter of a resin component is from 40% by mass to 80% by mass; in differential scanning calorimeter measurement of the tetrahydrofuran-insoluble matter, where a temperature of a maximum endothermic peak is denoted by Tm [° C.] and an endothermic quantity is denoted by H(I) [J/g], the following formulas (1) and (2) are satisfied: 55.0?Tm?80.0??(1) 10.0?H(I)?80.0??(2).

Abstract: A toner includes a toner particle containing a resin component including a crystalline resin and an amorphous resin. In a cross-sectional observation of the toner particle, a domain-matrix structure which comprises a matrix containing the crystalline resin and domains containing the amorphous resin is observed. The maximum endothermic peak temperature Tm of the toner determined by DSC is 50° C. to 80° C. When the storage elastic modulus of the toner at a temperature 5° C. lower than Tm is G?(?5) (Pa), and the storage elastic modulus of the toner at a temperature 5° C. higher than Tm is G?(+5) (Pa), G?(?5) and G?(+5) satisfy inequality (1), and when the maximum loss tangent of the toner in a temperature range of from 50° C. to 130° C. is tan ? (Max), tan ? (Max) satisfies inequality (2).

Abstract: A toner including toner particles having a resin component containing a crystalline resin and an amorphous resin, in which the resin component contains a tetrahydrofuran-insoluble component, and the content of the tetrahydrofuran-insoluble component with respect to the content of the resin component is 5.0% to 80.0% by mass, wherein a maximum endothermic peak temperature of the tetrahydrofuran-insoluble component is 55.0 to 80.0° C., and the amount of heat absorption in the maximum endothermic peak of the tetrahydrofuran-insoluble component is 10.0 to 80.0 Pa, and toner particles have a structure which comprises a matrix containing the crystalline resin and domains containing the amorphous resin.

Abstract: A toner is provided, which has a toner particle that contains a binder resin, and organosilicon polymer particle on a surface of the toner particle. A methanol concentration a (vol %) of the organosilicon polymer particle in a wettability test and a methanol concentration b (vol %) of the toner particle in a wettability test satisfy Expression (I) below: |a?b|?25??(I), and an adhesion index of the organosilicon polymer particle on a polycarbonate film, calculated on the basis of Expression (II) below, is not more than 3.

Abstract: A toner comprising a toner particle containing a binder resin, the storage elastic modulus Gt? (150) of the toner at 150° C. is at least 1.0×104 Pa, the binder resin contains a polymer A having a first monomer unit derived from a first polymerizable monomer and a second monomer unit derived from a second polymerizable monomer different from the first polymerizable monomer, the first polymerizable monomer is selected from specific (meth)acrylic acid esters, the contents of the first monomer unit and second monomer unit in the polymer A are within specific ranges, and the SP values of the first monomer unit and second monomer unit are within specific ranges.

Abstract: A magnetic toner comprising a magnetic toner particle including a binder resin, a magnetic body and a crystalline polyester, wherein in cross-sectional observation of the magnetic toner particle using a transmission electron microscope, a variation coefficient CV3 of an occupied area ratio of the magnetic body when a cross section of the magnetic toner particle is divided by a square grid having a side of 0.8 ?m is from 40.0% to 80.0%, and assuming that a storage elastic modulus at 40° C. is taken as E?(40) [Pa] and a storage elastic modulus at 85° C. is taken as E?(85) [Pa], the storage elastic moduli being obtained in a powder dynamic viscoelasticity measurement of the magnetic toner, the following formulas (1) and (2) are satisfied. E?(85)?2.

Abstract: Provided is a magnetic toner having a toner particle containing a binder resin and a magnetic body, wherein the binder resin contains a polymer A having a first monomer unit and a second monomer unit, the first polymerizable monomer is at least one selected from the group consisting of the (meth)acrylic acid esters having C18-36 alkyl groups, a content of the first monomer unit and a content of the second monomer unit based on the total moles of all monomer units in the polymer A are respectively 5.0 to 60.0 mol % and 20.0 to 95.0 mol %, and assuming that an SP value of the first monomer unit and the second monomer unit are taken as SP11 (J/cm3)0.5 and SP21(J/cm3)0.5, respectively, 3.00?(SP21?SP11)?25.00 is satisfied, and an oil absorption of the magnetic body is 5 to 40 ml/100 g.