An electrophotographic photoreceptor includes a conductive substrate and a photosensitive layer disposed on the conductive substrate which serves as an outermost surface of the electrophotographic photoreceptor. The electrophotographic photoreceptor satisfies YCYA0.1 MPa, YCYB0.1 MPa, and YC4.5 MPa, where YA, YB, and YC (MPa) represent the Young's moduli of a surface of the photosensitive layer determined by nanoindentation at an indentation depth of 500 nm at end portions A and B extending from a position 10 mm to a position 70 mm from the respective edges of the photosensitive layer toward the center of the photosensitive layer in an axial direction of the electrophotographic photoreceptor and a central portion C extending from a position 20 mm in front of and to a position 20 mm behind the center of the photosensitive layer in the axial direction of the electrophotographic photoreceptor, respectively.

Provided is an electrophotographic photoreceptor including a conductive support, a photosensitive layer, and a surface protective layer disposed in sequence. The surface protective layer includes a cured product of a composition containing a polymerizable compound, a charge transporting material, and at least two polymerization initiators. The polymerization initiators include an acyl phosphine oxide and an O-acyl oxime.

Provided is an electro-conductive belt including an electro-conductive resin layer. The electro-conductive resin layer includes a matrix containing a thermoplastic resin having at least one bond selected from the group consisting of an amide bond, an ester bond and a carbonate bond, a domain containing an ionic liquid containing a hexafluorophosphate anion or an anion expressed by formula (1), and particles containing a silicone resin having a structure expressed by formula (2): R.sub.0SiO.sub.3/2. Formula (1) ##STR00001##

An electrophotographic photoreceptor includes a conductive substrate and a single-layer-type photosensitive layer on the conductive substrate. The single-layer-type photosensitive layer contains a binder resin, a charge generating material, an electron transporting material, and a hole transporting material. The product of a volume resistivity (G.Math.m) of the single-layer-type photosensitive layer and an elastic modulus (GPa) of the single-layer-type photosensitive layer is about 90 or more.

An electrophotographic photoreceptor includes a conductive substrate and a photosensitive layer disposed on the conductive substrate which serves as an outermost surface of the electrophotographic photoreceptor. The electrophotographic photoreceptor satisfies YCYA0.1 MPa, YCYB0.1 MPa, and YC4.5 MPa, where YA, YB, and YC (MPa) represent the Young's moduli of a surface of the photosensitive layer determined by nanoindentation at an indentation depth of 500 nm at end portions A and B extending from a position 10 mm to a position 70 mm from the respective edges of the photosensitive layer toward the center of the photosensitive layer in an axial direction of the electrophotographic photoreceptor and a central portion C extending from a position 20 mm in front of and to a position 20 mm behind the center of the photosensitive layer in the axial direction of the electrophotographic photoreceptor, respectively.

Provided is an electrophotographic photoreceptor including a conductive support, a photosensitive layer, and a surface protective layer disposed in sequence. The surface protective layer includes a cured product of a composition containing a polymerizable compound, a charge transporting material, and at least two polymerization initiators. The polymerization initiators include an acyl phosphine oxide and an O-acyl oxime.

An electrophotographic photosensitive member includes: a support; an undercoat layer; a charge generation layer; and a charge transport layer, wherein the undercoat layer contains a polyamide resin and a titanium oxide fine particle, and on the surface of the undercoat layer, an arithmetic mean roughness Ra and an average length Rsm of a roughness curve element both according to JIS B0601:2001 satisfy Ra50 nm and 0.1Ra/Rsm0.5; and the charge generation layer contains a hydroxygallium phthalocyanine pigment, wherein the hydroxygallium phthalocyanine pigment includes crystal particles having a crystal form exhibiting peaks at 7.40.3 and 28.20.3 at Bragg angles 2 in a spectrum of X-ray diffraction using a CuK, ray; and in a size distribution of the crystal particles, which is measured using small-angle X-ray scattering, a peak exists in a range of 20 to 50 nm, and the peak has a half-value width of 50 nm or smaller.