Abstract: To provide a coating fluid for forming an undercoat layer having high stability, a high quality and long-life electrophotographic photoreceptor capable of forming a high quality image in various environments, with which image defects such as black spots or color spots hardly occur, an image forming apparatus using such a photoreceptor, and an electrophotographic cartridge using such a photoreceptor. A coating fluid for forming un undercoat layer of an electrophotographic photoreceptor containing titanium oxide particles and a binder resin, characterized in that titanium oxide agglomerated secondary particles in the coating fluid have a volume average particle size of at most 0.1 ?m and a cumulative 90% particle size of at most 0.3 ?m.

Abstract: An electrophotographic photoreceptor, comprising an electroconductive substrate, an undercoat layer comprising a binder resin and metal oxide particles having a refractive index of at least 2.0 formed on the electroconductive substrate, and a photosensitive layer formed on the undercoat layer, wherein a ratio of a specular reflection of the undercoat layer calculated as a thickness of 2 ?m to a light having a wavelength of 480 nm, to the specular reflection of the electroconductive substrate to a light having a wavelength of 480 nm, is at least 50%.

Abstract: Provided is an electrophotographic photoreceptor that is excellent in electric characteristics and can form a high-quality image having reduced ghosting. In the electrophotographic photoreceptor including an undercoat layer containing metal oxide particles and a binder resin on an electroconductive support, and a photosensitive layer disposed on the undercoat layer, the metal oxide particles have a volume average particle diameter of 0.1 ?m or less and a 90% cumulative particle diameter of 0.3 ?m or less which are measured by a dynamic light-scattering method in a liquid containing the undercoat layer dispersed in a solvent mixture of methanol and 1-propanol at a weight ratio of 7:3; and the photosensitive layer contains a compound represented by the following Formula (I): where Formula (I), Ar1 to Ar6 each independently represent an aromatic moiety that may have a substituent; X represents an organic moiety that may have a substituent; and n1 and n2 each independently represent an integer of 0 to 2.

Abstract: Provided are a coating liquid for forming an undercoat layer exhibiting high stability, a process for forming the coating liquid, a high-performance electrophotographic photoreceptor that is capable of forming a high-quality image under various use environments and exhibiting reduced image defects such as black spots and color spots, and an image-forming apparatus and electrophotographic cartridge including the electrophotographic photoreceptor. In the coating liquid for forming an undercoat layer of an electrophotographic photoreceptor containing metal oxide particles and a binder resin, the metal oxide particles have a number average particle diameter of 0.10?m or less and a 10% cumulative particle diameter of 0.060 ?m or less which are measured by a dynamic light-scattering method in the coating liquid for forming an undercoat layer.

Abstract: Provided is a coating liquid for forming an undercoat layer of an electrophotographic photoreceptor exhibiting high stability. In the coating liquid for forming an undercoat layer of an electrophotographic photoreceptor containing metal oxide particles and a binder resin, the metal oxide particles have a cumulative volume average diameter D50 of 0.1 ?m or less and a volume particle size distribution width index SD satisfying the following Expression (1) which are measured by a dynamic light-scattering method in the coating liquid for forming an undercoat layer, 0.010?SD?0.040??(1) where SD=(D84?D16)/2, where D84 represents the particle diameter (?m) at a point of 84% in the cumulative volume particle size distribution curve, and D16 represents the particle diameter (?m) at a point of 16% in the cumulative volume particle size distribution curve.

Abstract: An electrophotographic photoreceptor having high sensitivity and hardly affected by the transfer in an electrophotographic process is provided. The electrophotographic photoreceptor includes an undercoat layer containing metal oxide particles and a binder resin and a photosensitive layer disposed on the undercoat layer, wherein the metal oxide particles have a volume average particle diameter of 0.1 ?m or less and a 90% cumulative particle diameter of 0.3 ?m or less which are measured by a dynamic light-scattering method in a liquid of the undercoat layer dispersed in a solvent mixture of methanol and 1-propanol at a weight ratio of 7:3, and the photosensitive layer contains a binder resin having an ester bond.

Abstract: A coating fluid for photosensitive-layer formation having high productivity and stability and a process thereof are provided. Also provided are a high-performance electrophotographic photoreceptor and an image-forming apparatus which are capable of forming high-quality images even in various use environments and are less apt to cause image defects such as black spots or color spots. The objects are accomplished with a process for producing a coating fluid which is for forming a photosensitive layer of an electrophotographic photoreceptor and comprises a charge-generating material and a binder resin, wherein a dispersing medium having an average particle diameter in the range of from 1.0 ?m to 350 ?m is used as a dispersing medium for dispersing the charge-generating material in the coating fluid for photosensitive-layer formation. The coating fluid for photosensitive-layer formation produced by this process is preferable as a photosensitive layer of an electrophotographic photoreceptor.

Abstract: To provide a coating fluid for forming an undercoat layer having high stability, a high quality and long-life electrophotographic photoreceptor capable of forming a high quality image in various environments, with which image defects such as black spots or color spots hardly occur, an image forming apparatus using such a photoreceptor, and an electrophotographic cartridge using such a photoreceptor. A coating fluid for forming un undercoat layer of an electrophotographic photoreceptor containing titanium oxide particles and a binder resin, characterized in that titanium oxide agglomerated secondary particles in the coating fluid have a volume average particle size of at most 0.1 ?m and a cumulative 90% particle size of at most 0.3 ?m.

Abstract: An electrophotographic photoreceptor having high sensitivity and low residual potential is provided. The electrophotographic photoreceptor includes an undercoat layer containing metal oxide particles and a binder resin on an electroconductive substrate, and a photosensitive layer disposed on the undercoat layer, wherein the metal oxide particles have a volume average particle diameter of 0.1 ?m or less and a 90% cumulative particle diameter of 0.3 ?m or less which are measured by a dynamic light-scattering method in a liquid of the undercoat layer dispersed in a solvent mixture of methanol and 1-propanol at a weight ratio of 7:3; and the photosensitive layer contains crystalline phthalocyanine showing at least one distinct main diffraction peak at a Bragg angle (2?±0.2°) of 27.0° to 29.0° in an X-ray diffraction spectrum.