An electrophotographic photoreceptor having at least a photoreceptive layer, which comprises one or more layers, on a conductive base, wherein a surface layer of the photoreceptive layer contains a binder resin and silica particles, wherein the silica particles have a specific number average primary particle diameter and are contained at a specific ratio with respect to a total solid content in the surface layer, wherein the binder resin is made of a specific polycarbonate resin, wherein an area at a center part of a charged area in an axial direction of the electrophotographic photoreceptor on a surface of the surface layer of the photoreceptive layer has a specific average spacing Sm of irregularities, wherein the surface of the surface layer of the photoreceptive layer has a specific contact angle to pure water.

An electrophotographic photoreceptor having at least a photoreceptive layer, which comprises one or more layers, on a conductive base, wherein a surface layer of the photoreceptive layer contains a binder resin and silica particles, wherein the silica particles have a specific number average primary particle diameter and are contained at a specific ratio with respect to a total solid content in the surface layer, wherein the binder resin is made of a specific polycarbonate resin, wherein an area at a center part of a charged area in an axial direction of the electrophotographic photoreceptor on a surface of the surface layer of the photoreceptive layer has a specific average spacing Sm of irregularities, wherein the surface of the surface layer of the photoreceptive layer has a specific contact angle to pure water.

An electrophotographic photosensitive member that can resist mass printing. The electrophotographic photosensitive member is an electrophotographic photosensitive member including a surface layer containing a binder resin and inorganic particles. The surface layer contains a urethane resin as the binder resin, wherein the value of the ratio of the volume of the inorganic particles to the volume of the binder resin in the surface layer is 0.10 or more and 3.0 or less. Protrusions derived from the inorganic particles are present on the surface of the surface layer. The inorganic particles to be incorporated into the surface layer have a number-based average primary particle diameter of 10 nm or more and 500 nm or less. The surface of the surface layer has a maximum height roughness Rz of 10 nm or more and 760 nm or less.

An electrophotographic photosensitive member that can resist mass printing. The electrophotographic photosensitive member is an electrophotographic photosensitive member including a surface layer containing a binder resin and inorganic particles. The surface layer contains a urethane resin as the binder resin, wherein the value of the ratio of the volume of the inorganic particles to the volume of the binder resin in the surface layer is 0.10 or more and 3.0 or less. Protrusions derived from the inorganic particles are present on the surface of the surface layer. The inorganic particles to be incorporated into the surface layer have a number-based average primary particle diameter of 10 nm or more and 500 nm or less. The surface of the surface layer has a maximum height roughness Rz of 10 nm or more and 760 nm or less.

An image forming apparatus includes a photosensitive drum, first and second charging members, a development member, and first and second charging voltage applying units. The photosensitive drum includes a surface layer constituting a surface of the photosensitive drum. The second charging voltage applying unit applies a second charging voltage to the second charging member. The surface layer of the photosensitive drum has a volume resistivity of 1.0109 ohm centimeters (.Math.cm) or more and 1.01014 .Math.cm or less. The second charging voltage applying unit applies the second charging voltage such that a second potential difference formed between the second charging member and the surface of the photosensitive drum charged by the first charging member is equal to or higher than a discharge starting voltage.

An image forming apparatus includes a photosensitive drum, first and second charging members, a development member, and first and second charging voltage applying units. The photosensitive drum includes a surface layer constituting a surface of the photosensitive drum. The second charging voltage applying unit applies a second charging voltage to the second charging member. The surface layer of the photosensitive drum has a volume resistivity of 1.0109 ohm centimeters (.Math.cm) or more and 1.01014 .Math.cm or less. The second charging voltage applying unit applies the second charging voltage such that a second potential difference formed between the second charging member and the surface of the photosensitive drum charged by the first charging member is equal to or higher than a discharge starting voltage.

An electrophotographic photosensitive member includes a surface layer containing a binder resin and an inorganic particle. A value of a ratio of a volume of the inorganic particle to a volume of the binder resin in the surface layer is 1.0 or more and 4.0 or less. The binder resin is a polymerization product of a composition containing a polymerizable monomer having a polymerizable functional group. The composition contains a (meth)acrylic monomer having 6 or more polymerizable functional groups. The (meth)acrylic monomer has a molecular weight of 540 or more and 1,300 or less. A content of the (meth)acrylic monomer in the composition is 40 mol % or more with respect to a total molar number of the polymerizable monomer in the composition. A surface of the surface layer has an arithmetic average roughness Rz of 150 nm or more and 400 nm or less.

An electrophotographic photosensitive member includes a surface layer containing a binder resin and an inorganic particle. A value of a ratio of a volume of the inorganic particle to a volume of the binder resin in the surface layer is 1.0 or more and 4.0 or less. The binder resin is a polymerization product of a composition containing a polymerizable monomer having a polymerizable functional group. The composition contains a (meth)acrylic monomer having 6 or more polymerizable functional groups. The (meth)acrylic monomer has a molecular weight of 540 or more and 1,300 or less. A content of the (meth)acrylic monomer in the composition is 40 mol % or more with respect to a total molar number of the polymerizable monomer in the composition. A surface of the surface layer has an arithmetic average roughness Rz of 150 nm or more and 400 nm or less.

An electrophotographic photosensitive member includes a support, a photosensitive layer, and a surface layer. The surface layer includes a cured product of a composition containing an organic salt having a polymerizable functional group, and at least one of a charge-transportable compound or electroconductive particles. The organic salt is formed of an organic cation and at least one of BF.sub.4.sup., PF.sub.6.sup., (CF.sub.3SO.sub.2).sub.2N.sup., CF.sub.3SO.sub.3.sup., (FSO.sub.2)N.sup., C.sub.2H.sub.5OSO.sub.3.sup., (CN).sub.2N.sup., SCN.sup., CH.sub.3COO.sup., NO.sub.3.sup., Cl.sup., Br.sup. or I.sup..

An electrophotographic photosensitive member includes a support, a photosensitive layer, and a surface layer. The surface layer includes a cured product of a composition containing an organic salt having a polymerizable functional group, and at least one of a charge-transportable compound or electroconductive particles. The organic salt is formed of an organic cation and at least one of BF.sub.4.sup., PF.sub.6.sup., (CF.sub.3SO.sub.2).sub.2N.sup., CF.sub.3SO.sub.3.sup., (FSO.sub.2)N.sup., C.sub.2H.sub.5OSO.sub.3.sup., (CN).sub.2N.sup., SCN.sup., CH.sub.3COO.sup., NO.sub.3.sup., Cl.sup., Br.sup. or I.sup..