Abstract: An electrophotographic developing roller in which air tightness and electrical conductivity in a fit section between a cylindrical metal base body and a metal flange are satisfactory and outside diameter deflection accuracy is satisfactory; and an electrophotographic developing roller which is relatively inexpensive, excellent in mechanical rigidity, surface processability and plating film formation (corrosion resistance) and capable of being satisfied with a prescribed dimensional accuracy are provided. The electrophotographic developing roller is a developing roller having a cylindrical metal base body and a metal flange. The metal flange has a larger diameter section to be fitted in the opening end inner surface of the cylindrical metal base body and a smaller diameter section serving as a central shaft body coaxial with the cylindrical metal base body.

Abstract: A multi-layered organic electrophotographic photoconductor exhibits superior stability in mass production and excellent adhesion ability with two layers contacting the charge generation layer and is free of contamination of the coating liquid for a charge transport layer during a dip-coating process due to dissolution of the charge generation layer. The multi-layered organic electrophotographic photoconductor includes a conductive substrate and layers including an undercoat layer containing a thermosetting resin, a charge generation layer containing a charge generation material and an organic binder resin, and a charge transport layer laminated sequentially on the substrate, wherein polydispersity defined by a ratio of a weight average molecular weight to a number average molecular weight of the organic binder resin is at least 4.0, and the weight average molecular weight is at least 7.0×104 in a distribution of a polystyrene-converted molecular weight obtained by gel permeation chromatography.

Abstract: An electrophotographic developing roller in which air tightness and electrical conductivity in a fit section between a cylindrical metal base body and a metal flange are satisfactory and outside diameter deflection accuracy is satisfactory; and an electrophotographic developing roller which is relatively inexpensive, excellent in mechanical rigidity, surface processability and plating film formation (corrosion resistance) and capable of being satisfied with a prescribed dimensional accuracy are provided. The electrophotographic developing roller is a developing roller having a cylindrical metal base body and a metal flange. The metal flange has a larger diameter section to be fitted in the opening end inner surface of the cylindrical metal base body and a smaller diameter section serving as a central shaft body coaxial with the cylindrical metal base body.

Abstract: An electrophotographic photoconductor includes a photosensitive layer on a conductive substrate. The photosensitive layer contains a pigment that consists of crystallites composed of molecules having a titanylphthalocyanine structure, wherein a crystallite diameter of the pigment is not smaller than 20 nm and a primary particle diameter of the pigment is not larger than 500 nm.

Abstract: A highly sensitive positively charged type electrophotographic photoconductor includes an organic compound that transports electrons efficiently, improving light emission efficiency. The photoconductor is used in an electrophotographic drum, an electrophotographic cartridge and an electrophotographic apparatus.

Abstract: An electrophotographic photoreceptor has excellent electrical properties and is stable even upon repeated use. An electrophotographic apparatus using the electrophotographic photoreceptor uses a compound having an excellent electron transporting ability in a photosensitive layer of the electrophotographic photoreceptor. An electrophotographic photoreceptor, in which a photosensitive layer is located on an electrically conductive substrate either directly or via an undercoat layer, contains a compound having a structure represented by the general formula (I). An electrophotographic apparatus contains the above-mentioned electrophotographic photoreceptor, and carries out a charging process through a positive charging process.

Abstract: Quinomethane compounds having a structure represented by the general formula (1): wherein R1 to R4 and R9 to R12 are the same or different and each represents a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, a cyclic alkyl group, an aryl group, or an alkoxy group having 1 to 6 carbon atoms; R5 and R6 are the same or different and each represents an alkyl group having 1 to 12 carbon atoms, an aryl group, or a heterocyclic group; R7 and R8 each represents a hydrogen atom; and optional substituents are each a halogen atom, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an aryl group, or a heterocyclic group. Since these compounds transport electrons efficiently, they are useful in electrophotographic photoreceptors and/or organic electroluminescence applications.

Abstract: A photoconductor for electrophotography including a conductive substrate, an undercoat layer provided on the conductive substrate, and a photosensitive layer provided on the undercoat layer and a manufacturing method thereof. The undercoat layer contains metallic oxide fine particles and is formed by applying a coating liquid for the undercoat layer onto the conductive substrate. The coating liquid contains an organic solvent having a boiling point at 1×105Pa of about 160° C. or less and a viscosity at 20° C. of about 3.0 mPa.s or more. This improves dispersion stability of metal oxide fine particles in the coating liquid to realize a uniform undercoat layer and, in turn, provides the photoconductor with uniform electrophotographic characteristics, in particular, with uniform image characteristics and external appearance characteristics.

Abstract: A multi-layered organic electrophotographic photoconductor exhibits superior stability in mass production and excellent adhesion ability with two layers contacting the charge generation layer and is free of contamination of the coating liquid for a charge transport layer during a dip-coating process due to dissolution of the charge generation layer. The multi-layered organic electrophotographic photoconductor includes a conductive substrate and layers including an undercoat layer containing a thermosetting resin, a charge generation layer containing a charge generation material and an organic binder resin, and a charge transport layer laminated sequentially on the substrate, wherein polydispersity defined by a ratio of a weight average molecular weight to a number average molecular weight of the organic binder resin is at least 4.0, and the weight average molecular weight is at least 7.0×104 in a distribution of a polystyrene-converted molecular weight obtained by gel permeation chromatography.

Abstract: Disclosed is a positive charging single-layer organic photoreceptor for liquid development which comprises a conductive substrate having thereon a photosensitive layer containing a charge generating material, an electron transport material and an organic binder resin comprising a polymer represented by formula (I): wherein R1 and R2 each represent a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group, or R1 and R2 may form a cycloalkyl group in combination; R3, R4, R5, R6, R7, R8, R9, R10 and R11, each represent a hydrogen atom, a halogen atom, an aryl group or an alkyl group; and m and n each represent a molar percentage giving a total of 70 to 95 mol %.

Abstract: The object of the present invention is to provide an electrophotography photosensitive body substrate, photosensitive body, and electrophotography device used in a contact charging process that can prevent the occurrence of minor insulation damage of around diameter 0.1-0.5 mm. In an electrophotography photosensitive body substrate having a sealed aluminum anodic oxidation film on its surface, the anodic oxidation film is sealed by a sealing agent in which an anion surface active agent is beneficially added.

Abstract: An electrophotographic photoconductor and method of manufacturing thereof exhibits excellent characteristics of residual potential and repetition potential by containment of an additive of a compound. The electrophotographic photoconductor includes a conductive substrate and a photosensitive layer on the substrate, in which the photosensitive layer contains tri(4-nitrophenyl) phosphate.

Abstract: A highly sensitive positively charged type electrophotographic photoconductor includes an organic compound that transports electrons efficiently, improving light emission efficiency. The photoconductor is used in an electrophotographic drum, an electrophotographic cartridge and an electrophotographic apparatus.

Abstract: An electrophotographic photoconductor exhibits excellent electrophotographic performance, particularly high sensitivity. A method of manufacturing an electrophotographic photoconductor includes forming a photosensitive layer exhibiting high sensitivity using a coating liquid. The electrophotographic photoconductor includes a photosensitive layer that contains photoconductive substances, a principal component of which is a metallophthalocyanine compound and a subcomponent of which is a phthalocyanine compound having central elements of hydrogen. The content of the subcomponent is in a proportion of 1 &mgr;mol to 200 mmol with respect to 1 mol of the principal component. The manufacturing method uses a coating liquid containing photoconductive substances, including principal component of a metallophthalocyanine compound and a subcomponent of a phthalocyanine compound having central elements of hydrogen in a proportion of 1 &mgr;mol to 200 mmol with respect to 1 mol of the principal component.

Abstract: An electrophotographic photoreceptor has excellent electrical properties and is stable even upon repeated use. An electrophotographic apparatus using the electrophotographic photoreceptor uses a compound having an excellent electron transporting ability in a photosensitive layer of the electrophotographic photoreceptor. An electrophotographic photoreceptor, in which a photosensitive layer is located on an electrically conductive substrate either directly or via an undercoat layer, contains a compound having a structure represented by the general formula (I).

Abstract: Quinomethane compounds having a structure represented by the general formula (1): 1

Abstract: An electrophotographic photoconductor a substrate and a photosensitive layer on the substrate. The photosensitive layer contains charge generation substance, charge transport substance and a binder resin. The binder resin has a dispersion d1=Mz/Mw of at least 1.6, and/or a polydispersity d2=Mw/Mn of at least 2.0, each of d1 and d2 being an indicator of a range of molecular weight distribution converted to polystyrene standard, wherein Mz, Mw and Mn are a z-average molecular weight, a weight-average molecular weight, and a number-average molecular weight of the binder resin, respectively. The resulting electrophotographic photoconductor minimizes film abrasion and filming, allowing the photoconductor to possess stable characteristics in repeated use over long periods.

Abstract: A phthalimide salt compound is contained in a photosensitive material having a charge generating function. Such a photosensitive material exhibits high retention rates of the surface charge. An electrophotographic photoconductor comprising such a photosensitive material is useful in, for example, printers, photocopiers, and facsmilie machines.

Abstract: Disclosed is a positive charging single-layer organic photoreceptor for liquid development which comprises a conductive substrate having thereon a photosensitive layer containing a charge generating material, an electron transport material and an organic binder resin comprising a polymer represented by formula (I): 1

Abstract: A photoconductor for electrophotography including a conductive substrate, an undercoat layer provided on the conductive substrate, and a photosensitive layer provided on the undercoat layer and a manufacturing method thereof. The undercoat layer contains metallic oxide fine particles and is formed by applying a coating liquid for the undercoat layer onto the conductive substrate. The coating liquid contains an organic solvent having a boiling point at 1×105Pa of about 160° C. or less and a viscosity at 20° C. of about 3.0 mPa.s or more. This improves dispersion stability of metal oxide fine particles in the coating liquid to realize a uniform undercoat layer and, in turn, provides the photoconductor with uniform electrophotographic characteristics, in particular, with uniform image characteristics and external appearance characteristics.