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: 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 non 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 is a second region defined in this specification, to aggregates of the 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 fluorine-containing resin particles in the first region is within a range of 1±0.1.

Abstract: A charging device includes: a charging member that charges an electrophotographic photoconductor by a contact charging method and includes a conductive substrate, an elastic layer provided on the conductive substrate, and a surface layer that is provided on the elastic layer and contains irregularities-forming particles that have a number particle size distribution with two or more maximum values when observed, from a surface of the surface layer, and a voltage application unit that applies, to the charging member, an AC voltage superimposed on a DC voltage.

Abstract: A charging device includes a charging roller and a cleaning roller that includes a core and a foamed elastic layer disposed on an outer circumferential surface of the core and that rotates in contact with a surface of the charging roller. The number of ends of a cell skeleton that protrude from a surface of the foamed elastic layer is 25 ends/mm2 or more and 50 ends/mm2 or less. The cleaning roller is disposed in contact with the charging roller such that the compression ratio of the foamed elastic layer is 30% or less. The compression ratio is represented by Equation (1): compression ratio (%)=(r1/2+r2/2?d)/t1×100??Equation (1): where r1 is the outer diameter (mm) of the cleaning roller, r2 is the outer diameter (mm) of the charging roller, d is the interaxial distance (mm) between the charging roller and the cleaning roller, and t1 is the thickness (mm) of the foamed elastic layer of the cleaning roller.

Abstract: A porous membrane includes a porous membrane base containing a polymer compound and having pores interconnected in a thickness direction, and a metal oxide film on inner wall surfaces of the pores.

Abstract: A height of convexities in a 0.7-mm-square area of a surface of the charging member is measured at five or more different positions in an axial direction and calculated. A height of a position where the charging member occupies 0.01 area % from a highest portion is defined as a reference height. An average proportion of areas occupied by the charging member at a position 1.7 ?m lower than the reference height is 2 area % or less relative to 100 area % of the 0.7-mm-square area.

Abstract: A height of convexities in a 0.7-mm-square area of a surface of the charging member is measured at five or more different positions in an axial direction and calculated. A height of a position where the charging member occupies 0.01 area % from a highest portion is defined as a reference height. An average proportion of areas occupied by the charging member at a position 1.7 ?m lower than the reference height is 2 area % or less relative to 100 area % of the 0.7-mm-square area.

Abstract: Provided is an electrophotographic photoreceptor including a conductive substrate and a photosensitive layer provided on the conductive substrate, wherein an uppermost surface layer thereof is constituted with a cured film of a composition that contains at least two kinds of reactive charge transporting materials selected from a first reactive charge transporting material having an —OH group as a reactive functional group and a second reactive charge transporting material having an —OCH3 group as a reactive functional group, fluororesin particles, and an alkyl fluoride group-containing copolymer having repeating units represented by the following Structural Formulae A and B, and a relative dielectric constant ?r of the uppermost surface layer satisfies the following Formula (1):

Abstract: There is provided an electrophotographic photoreceptor including a conductive substrate; an intermediate layer; a photosensitive layer; and a surface layer, in this order, the surface layer including two or more charge transporting materials each including a reactive substituent and respectively having mutually different ionization potentials, in an amount of 90% by weight or more relative to the total solid content of the surface layer, and the content ratio X of each of the two or more charge transporting materials satisfying the following Formula (1).

Abstract: An electrophotographic photoreceptor includes a cylindrical conductive substrate that is formed of a metal or an alloy and has an average area of crystal grains of 100 ?m2 or greater; and a photosensitive layer that is provided on the conductive substrate.

Abstract: Provided is an electrophotographic photoreceptor including a conductive substrate and a photosensitive layer provided on the conductive substrate, wherein an uppermost surface layer thereof is constituted with a cured film of a composition that contains at least two kinds of reactive charge transporting materials selected from a first reactive charge transporting material having an —OH group as a reactive functional group and a second reactive charge transporting material having an —OCH3 group as a reactive functional group, fluororesin particles, and an alkyl fluoride group-containing copolymer having repeating units represented by the following Structural Formulae A and B, and a relative dielectric constant ?r of the uppermost surface layer satisfies the following Formula (1):

Abstract: The endless belt is provided with: a metal layer that includes at least one layer, that is cylindrically formed, and that has not more than 10 degrees as a half width of a diffraction peak in X-ray diffraction; and a release layer that is stacked on the metal layer.

Abstract: There is provided an electrophotographic photoreceptor including a conductive substrate; an intermediate layer; a photosensitive layer; and a surface layer, in this order, the surface layer including two or more charge transporting materials each including a reactive substituent and respectively having mutually different ionization potentials, in an amount of 90% by weight or more relative to the total solid content of the surface layer, and the content ratio X of each of the two or more charge transporting materials satisfying the following Formula (1).

Abstract: The endless belt is provided with: a metal layer that includes at least one layer, that is cylindrically formed, and that has not more than 10 degrees as a half width of a diffraction peak in X-ray diffraction; and a release layer that is stacked on the metal layer.