There is provided an electrophotographic photosensitive member that can achieve both of an adequately high initial sensitivity as the electrophotographic photosensitive member and reduction in the fluctuation of a light portion potential at the time of repeated use. An electrophotographic photosensitive member includes a support, an electroconductive layer and a photosensitive layer in this order, wherein the electroconductive layer contains a binder material and a metal oxide particle; the metal oxide particle has a core material containing a titanium oxide, and a covering layer which covers the core material and contains the titanium oxide; and when the oxygen deficiency ratio of the metal oxide particle is represented by A, the oxygen deficiency ratio of the core material is represented by B, and the oxygen deficiency ratio of the covering layer is represented by C, the Expressions (1) and (2) are satisfied: A2% (1) and 10B<C (2).

There is provided an electrophotographic photosensitive member that can achieve both of an adequately high initial sensitivity as the electrophotographic photosensitive member and reduction in the fluctuation of a light portion potential at the time of repeated use. An electrophotographic photosensitive member includes a support, an electroconductive layer and a photosensitive layer in this order, wherein the electroconductive layer contains a binder material and a metal oxide particle; the metal oxide particle has a core material containing a titanium oxide, and a covering layer which covers the core material and contains the titanium oxide; and when the oxygen deficiency ratio of the metal oxide particle is represented by A, the oxygen deficiency ratio of the core material is represented by B, and the oxygen deficiency ratio of the covering layer is represented by C, the Expressions (1) and (2) are satisfied: A2% (1) and 10B<C (2).

An electrophotographic photoconductor includes a conductive substrate; and a photosensitive layer provided on the conductive substrate and containing a charge generation material, a hole transport material, a first electron transport material, from 3% by mass to 40% by mass of a second electron transport material, a resin binder, and an inorganic oxide filler surface-treated with a silane coupling agent. In a dipole-dipole force component (a Hansen solubility parameter), the first electron transport material and the silane coupling agent have a difference of SPa<2.50; the second electron transport material and the silane coupling agent have a difference of SPb<2.50; and the first electron transport material and the second electron transport material have a difference of 0.30<SPc<1.00. In a London dispersion force component (a Hansen solubility parameter), the resin binder and the silane coupling agent have a difference of SPd<2.00.

An electrophotographic photoconductor includes a conductive substrate; and a photosensitive layer provided on the conductive substrate and containing a charge generation material, a hole transport material, a first electron transport material, from 3% by mass to 40% by mass of a second electron transport material, a resin binder, and an inorganic oxide filler surface-treated with a silane coupling agent. In a dipole-dipole force component (a Hansen solubility parameter), the first electron transport material and the silane coupling agent have a difference of SPa<2.50; the second electron transport material and the silane coupling agent have a difference of SPb<2.50; and the first electron transport material and the second electron transport material have a difference of 0.30<SPc<1.00. In a London dispersion force component (a Hansen solubility parameter), the resin binder and the silane coupling agent have a difference of SPd<2.00.

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 [.Math.cm], a volume resistivity of the electroconductive particles is represented by R2 [.Math.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.

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 [.Math.cm], a volume resistivity of the electroconductive particles is represented by R2 [.Math.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.

An electrophotographic photoreceptor includes an electroconductive substrate; and a photosensitive layer that is formed on the electroconductive substrate and that contains an inorganic oxide and a lubricant resin. When light having a wavelength of 780 nm is irradiated onto a slurry containing 20% by mass of the inorganic oxide in a predetermined solvent to provide an inorganic oxide slurry, the inorganic oxide slurry has a luminous transmittance that is 40% or more. The photosensitive layer may be a negatively-charged laminate-type photosensitive layer, a monolayer type photosensitive layer, or a positively-charged laminate-type photosensitive layer. The electrophotographic photoreceptor is less worn upon long-term use, allows no filming, and can realize stable images. A method for producing the electrophotographic photoreceptor and an electrophotographic apparatus including the electrophotographic photoreceptor are disclosed.

An electrophotographic photoreceptor includes an electroconductive substrate; and a photosensitive layer that is formed on the electroconductive substrate and that contains an inorganic oxide and a lubricant resin. When light having a wavelength of 780 nm is irradiated onto a slurry containing 20% by mass of the inorganic oxide in a predetermined solvent to provide an inorganic oxide slurry, the inorganic oxide slurry has a luminous transmittance that is 40% or more. The photosensitive layer may be a negatively-charged laminate-type photosensitive layer, a monolayer type photosensitive layer, or a positively-charged laminate-type photosensitive layer. The electrophotographic photoreceptor is less worn upon long-term use, allows no filming, and can realize stable images. A method for producing the electrophotographic photoreceptor and an electrophotographic apparatus including the electrophotographic photoreceptor are disclosed.

An electrophotographic photoconductor is provided that includes a conductive substrate, an undercoat layer overlying the conductive substrate, and a photosensitive layer overlying the undercoat layer. The undercoat layer contains zinc oxide particles and a binder resin and has a volume resistivity of 0.0310.sup.6 .Math.cm or less in an electrical field of 5 V/m at a temperature of 23 degrees C. and a relative humidity of 55%. The photosensitive layer contains a compound represented by the following general formula (1):

##STR00001##

where each of R.sub.1 to R.sub.3 independently represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 6 carbon atoms which may have a substituent, or a substituted or unsubstituted aryl group having 6 to 12 carbon atoms.

An electrophotographic photoconductor is provided that includes a conductive substrate, an undercoat layer overlying the conductive substrate, and a photosensitive layer overlying the undercoat layer. The undercoat layer contains zinc oxide particles and a binder resin and has a volume resistivity of 0.0310.sup.6 .Math.cm or less in an electrical field of 5 V/m at a temperature of 23 degrees C. and a relative humidity of 55%. The photosensitive layer contains a compound represented by the following general formula (1):

##STR00001##

where each of R.sub.1 to R.sub.3 independently represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 6 carbon atoms which may have a substituent, or a substituted or unsubstituted aryl group having 6 to 12 carbon atoms.