Abstract: A high-sensitivity and long-life electrophotographic photoreceptor comprising an electroconductive substrate and at least a photosensitive layer on the electroconductive substrate is provided, wherein the photosensitive layer contains a polyarylate resin not having a nitrogen atom in its repeating unit, and the Hall mobility at an electric field strength of 3×105 (V/cm) and at a temperature of 21° C. of the photosensitive layer is 3×10−6 (cm2/Vs) or more.

Abstract: A photoconductive imaging member comprised of an optional supporting substrate, an optional blocking layer, a photogenerating layer, and a charge transport layer, and a SiO3 containing polycarbonate component.

Abstract: A photoconductive imaging member comprised of an optional supporting substrate, an optional blocking layer, a photogenerating layer, and a charge transport layer, and wherein said charge transport layer comprises a crosslinked polycarbonate component containing a repeating segment of the formula 1

Abstract: An electrophotographic photoconductor has an electroconductive support, and a photoconductive layer formed thereon containing as an effective component an aromatic polycarbonate resin having a structural unit of formula (2) and a structural unit with charge transporting properties, each of the structural units being contained in an amount of 5 wt. % or more of the total weight of the polycarbonate resin. There is disclosed an aromatic polycarbonate resin having a structural unit of formula (1) and the structural unit of formula (2), with the relationship between the composition ratios being 0<k/(k+j)<1 when the composition ratio of the structural unit (1) is k and that of the structural unit (2) is j, or an aromatic polycarbonate resin having a repeat unit of formula (3). The formulas (1) to (3) are specified in the specification.

Abstract: Charge transport layers comprise a charge transport compound and binder including styrene-acrylic resin. Dual layer photoconductors comprise a substrate, a charge transport layer as described, and a charge generation layer.

Abstract: Disclosed is a binder-loaded type charge-transport liquid crystal material which comprises a liquid crystal compound and a binder and, in spite of the presence of the binder, can substantially retain the properties inherent in the liquid crystal compound.

Abstract: A composition is provided for coating a photoreceptor having a charge generating layer and a charge transport layer. The composition includes a hole transport material, a cross-linkable film forming binder having at least one functional group that is reactive with isocyanate, a blocked isocyanate cross-linking agent and a solvent having a boiling point equal to or below the deblocking temperature. The blocked isocyanate cross-linking agent is the reaction product of an isocyanate and a blocking agent, wherein the blocking agent has a boiling point temperature equal to or below a selected deblocking temperature to allow the isocyanate to form cross-links. The invention also provides an electrophotographic imaging member with an overcoat layer comprising a cross-linked film forming binder, an isocyanate compound, a hole transport material, and optionally a surface energy reducing agent. Processes for making the imaging members are also provided.

Abstract: A charge transport layer for an imaging member comprising a photogenerating layer, (1) a first charge transport layer comprised of a charge transport component and a resin binder, and thereover and in contact with the first layer (2) a second top charge transport layer comprised of a charge transport component, and a polymer of a styrene containing hindered phenol. The charge transport layer exhibits excellent wear resistance, excellent electrical performance, and outstanding print quality.

Abstract: A photoconductive imaging member comprised of a substrate, a photogenerating layer, and a charge transport layer containing a binder and a compound containing at least two (methyl)acrylates.

Abstract: A photoconductive imaging member containing a hole blocking layer, a photogenerating layer, a charge transport layer, and thereover an overcoat layer comprised of a polymer With a low dielectric constant and charge transport molecules.

Abstract: An imaging member including, for example, a substrate, a charge blocking layer, an optional adhesive layer, a charge generating layer, a charge transporting layer comprising a charge transport component and a polymer binder substantially free of low molecular weight fractions.

Abstract: An electrophotographic photoreceptor for wet development including an electrically conductive substrate, and an organic photosensitive layer formed on the electrically conductive substrate, wherein a surface layer of the organic photosensitive layer includes at least a binder resin comprising a polymer compound and a charge transport material comprising a low molecule compound, the surface layer having an oxygen gas permeation coefficient of 5×10−13 cm3 (STP)*cm/s*cm2*cmHg or less. The electrophotographic photoreceptor has high durability for liquid developer used in a wet development technique and can produce good image characteristics.

Abstract: An electrophotographic photoconductor has an electroconductive support and a photoconductive layer which is formed thereon and contains at least one resin of a polyurethane resin, a polyester resin, or a polycarbonate resin, each resin having at least a structural unit of formula (1): 1

Abstract: An imaging member having a charge transport layer is provided. The charge transport layer includes a plurality of charge transport layers coated from solutions of similar or different compositions or concentrations, wherein the upper or additional transport layer(s) comprise a lower concentration of charge transport compound than the first (bottom) charge transport layer. The charge transport compound included in the first (bottom) charge transport layer may either be the same or different from that included in the additional charge transport layers. The charge transport compound in one or more of the layers is dissolved or molecularly dispersed in an electrically inactive polymer material to form a solid solution. In such a construction, the resulting charge transport layer exhibits enhanced cracking suppression, improves wear resistance, provides excellent imaging member electrical performance, and delivers improved print quality.

Abstract: An imaging member having a charge transport layer with multiple regions is provided. The charge transport layer includes a plurality of charge transport layers coated from solutions of similar or different compositions or concentrations, wherein at least the top or uppermost transport layer comprises a lower concentration of charge transport compound than the first (bottom) charge transport layer. The charge transport compound included in the first (bottom) charge transport layer may either be of the same or different compounds from that included in the top or additional charge transport layer(s). The charge transport compound present in each layer may be dissolved or molecularly dispersed in an electrically inactive polymer material to form a solid solution. In such a construction, the resulting charge transport layer exhibits enhanced cracking suppression, improves wear resistance, provides excellent imaging member electrical performance, and delivers improved print quality.

Abstract: The present invention relates to the electrophotographic apparatus wherein the photoconductor takes 200 msec or less to reach from the light irradiator to the developer, an exposure energy upon irradiation of a write light having a resolution of 600 dpi or greater from the light irradiator to the photoconductor is 5 erg/cm2 or less on the surface thereof, the photoconductor is obtained by stacking a charge generation layer and a charge transport layer in this order on a conductive support, and the charge generation layer contains titanyl phthalocyanine crystals having, as a diffraction peak (±0.2°) of Bragg angle 2&thgr; relative to CuK&agr; ray (wavelength: 1.542 angstrom), a maximum diffraction peak at least at 27.2°, main peaks at 9.4°, 9.6° and 24.0°, and a peak at 7.3° as a diffraction peak on the lowest angle side, and not having a peak within a range of 7.4 to 9.3°.

Abstract: A charge transport layer for an imaging member comprising a photogenerating layer, (1) a first charge transport layer comprised of a charge transport component and a resin binder, and thereover and in contact with the first layer (2) a second top charge transport layer comprised of a charge transport component, and a polymer of a styrene containing hindered phenol.

Abstract: A charge transport layer for an imaging member comprising a charge transport layer wherein the charge transport layer is coated in two passes and wherein the second pass comprises the application of a charge transport component and a hindered phenol covalently bonded to a polymer. The charge transport layer exhibits excellent wear resistance, excellent electrical performance, and excellent print quality.

Abstract: A charge transport layer for an imaging member comprising a dual charge transport layer and wherein the charge transport layers comprise a photogenerating layer; (1) a first charge transport layer comprised of a charge transport component and a resin binder; and thereover and in contact with the first layer; (2) a second top charge transport layer comprised of a charge transport component, a resin binder and a hindered phenol dopant. The charge transport layer exhibits, excellent electrical performance, outstanding print quality and reduces the diffusion of the anti-oxidant into the charge generator layer.

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 present invention provides an electrophotosensitive material comprising a conductive substrate and a photosensitive layer provided on the conductive substrate, wherein the photosensitive layer contains a polyallylate having a repeating unit represented by the general formula (1): 1

Abstract: A double-layered positively-charged organic photoreceptor has a charge transport layer with effective adhesion to an electroconductive support and effective resistance against dissolving when in contact with a hydrocarbon-based solvent of a wet developer. Therefore, the double-layered positively-charged organic photoreceptor requires neither anodizing on the electroconductive support nor an additional adhesive layer, and is compatible with wet developing methods. The double-layered positively-charged organic photoreceptor includes: an electroconductive support; a charge transport layer formed on a surface of the electroconductive support and including a charge transport material for transporting holes, a polycarbonate-based first binder resin, and a second binder resin of a polyester copolymer with a biphenylfluorene group; and a charge generating layer formed on the surface of the charge transport layer.

Abstract: An electrophotographic photoreceptor includes a support, an undercoating, and a photosensitive layer, wherein the undercoating includes a charge transport material which is soluble in an organic solvent and a binder resin.

Abstract: An imaging member including, for example, a substrate, a charge blocking layer, an optional adhesive layer, a charge generating layer, a charge transporting layer comprising, and a film forming polymer binder substantially free of low molecular weight fractions.

Abstract: The present invention relates to a flexible electrostatographic imaging member. The electrostatographic imaging member contains an optically transparent thermoplastic anti-curl back coating, which enables the imaging member to maintain desirable structural flatness, mechanical robustness, flexibility, longevity, and copy image qualities over extended use. The present invention also relates to a process of fabricating a flexible electrostatographic imaging member.

Abstract: According to the present invention, there is provided: an electrophotographic photosensitive member having a photosensitive layer on a support in which a surface layer of the electrophotographic photosensitive member comprises an acrylic polymer having a polyfluoroolefin unit and an alkylene oxide unit, and having a number-average molecular weight in a range of 2,000 to 20,000; a process cartridge and an electrophotographic apparatus both comprising the electrophotographic photosensitive member.

Abstract: An electrophotographic photosensitive member having a surface layer containing at least one of a charge-transporting material and conductive particles and a polymer obtained by polymerizing at least one selected from the group consisting of a polyhydroxymethylbisphenol monomer having a specific structure, a polyhydroxymethylbisphenol oligomer having a specific structure, a polyhydroxymethyltrisphenol monomer having a specific structure and a polyhydroxymethyltrisphenol oligomer having a specific structure; and a process cartridge and an electrophotographic apparatus which have the electrophotographic photosensitive member.

Abstract: A member including for example, a substrate, a charge generating layer, a charge transport layer comprising a poly(phenylsilsesquioxane), molecule, and a film forming binder.

Abstract: An electrophotographic photoreceptor includes a photosensitive layer including a layer having at least one of a binder resin that includes a polymer compound and a hole transport material that includes a low-molecular weight compound, on an electrically conductive substrate, wherein the polymer compound is a polyester resin having a biphenylfluorene unit having a predetermined structure in a main chain, and the low-molecular weight compound is a stilbene compound having a predetermined structure. The electrophotographic photoreceptor according to the present invention has effective electrostatic properties and mechanical strength.

Abstract: An electrostatographic article including: a substrate; a charge generator layer overcoated on the substrate and which layer is sensitive to blue light; and a charge transport layer overcoated on the charge generator layer and which charge transport layer is transparent to blue light.

Abstract: Charge transport layers comprise a charge transport compound and binder including styrene-acrylic resin. Dual layer photoconductors comprise a substrate, a charge transport layer as described, and a charge generation layer.

Abstract: An electrophotographic image forming apparatus according to the present invention includes: a multiple number of image forming stations for multiple development colors including black, each station having a photoreceptor, an exposure device, a developing device for developing each static latent image with the toner of each development color; a recording media conveyer belt conveying, along the photoreceptors, a recording medium on which a monochrome toner image is formed or a color image is formed by overlapping multiple colors of toner images, wherein each of the photoreceptors has a charge transport layer composed of a binder resin that is a blend of at least two kinds of resins, the blended ratio of at least two kinds of binder resins for the photoreceptor for black is made different from that of the binder resins for the photoreceptors for the other development colors so that the photoreceptor for black presents a greater abrasion resistance than the photoreceptors for other development colors.

Abstract: An electrophotographic photoconductor has an electroconductive support and a photoconductive layer which is formed thereon and contains at least one resin of a polyurethane resin, a polyester resin, or a polycarbonate resin, each resin having at least a structural unit of formula (1): 1

Abstract: In an electrophotographic photosensitive member comprising a cylindrical support, and provided thereon a photosensitive layer and a protective layer in this order, which cylindrical support has an outer diameter of less than 30 mm, the difference between a coefficient of thermal expansion &agr;1 measured from the top of the protective layer and a coefficient of thermal expansion &agr;2 measured after the protective layer has been removed, |&agr;1−&agr;2|, is more than 5.0×10−7° C.−1 to less than 1.0×10−4° C.−1, and the modulus of elastic deformation We % measured from the top of the protective layer is more than 30% to less than 60%. Also disclosed are a process cartridge and an electrophotographic apparatus which have such an electrophotographic photosensitive member.

Abstract: An electrophotographic photosensitive member is disclosed in which a photosensitive layer and a protective layer are formed on a conductive substrate in that order. In this photosensitive member, when its surface is charged to −700 V under a 23° C./5% RH environment and irradiated with white light in a light quantity of 10 lux·sec, if the surface potential at the time 0.2 seconds have passed from the irradiation and the surface potential at the time 0.5 seconds have passed from the irradiation are defined as Vsl(0.2) and Vsl(0.5), respectively, the absolute value of Vsl(0.2) and the absolute value of Vsl(0.2)−Vsl(0.5) satisfy specific conditions.

Abstract: An electrophotographic imaging method, wherein a liquid developer directly contacts an electrophotographic organic photoreceptor to develop an image, utilizes a binder contained in a surface layer of the organic photoreceptor that comprises a polyester resin having a main chain of a biphenylfluorene repeating unit. Since the organic photoreceptor has effective initial electrostatic characteristics and experiences little change in electrostatic characteristics before and after soaking in a solvent for a liquid developer, even when the liquid developer directly contacts an organic photoreceptor, the organic photoreceptor is not eroded by the solvent, and the developer is not contaminated. Therefore, stable development can be performed.

Abstract: An electrophotographic photoreceptor is disclosed.

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 toner for electrophotography contains a binder resin and a colorant, the toner for electrophotography has a tensile fracture strength of 10-1400 (N/m2) under 10 kg/cm2 compression, and a loose apparent density of 0.10-0.50 (g/cm3).

Abstract: An electrophotographic photoreceptor is disclosed. A surface layer of the photoreceptor comprises binder resin having silicon or fluorine atoms and dioxolan or a derivative thereof at 0.001 to 10 weight percent.

Abstract: A high-sensitivity and long-life electrophotographic photoreceptor comprising an electroconductive substrate and at least a photosensitive layer on the electroconductive substrate is provided, wherein the photosensitive layer contains a polyarylate resin not having a nitrogen atom in its repeating unit, and the Hall mobility at an electric field strength of 3×105 (V/cm) and at a temperature of 21° C. of the photosensitive layer is 3×10−6 (cm2/Vs) or more.

Abstract: An electrophotographic photosensitive member having a photosensitive layer provided on an electro-conductive supporting substrate and a protection layer provided on the photosensitive layer, wherein the protection layer at least comprises a kind of finely divided metal oxide particle, an organic acid and a binder resin, the binder resin is a thermo-curable resin, and the organic acid being contained an amount of 0.05 wt. % to 5 wt. % for the amount of the thermo-curable resin. this photosensitive member has a high durability capable of stable image productions for a long period of utilizable time due to the protection layer.

Abstract: An image forming method wherein a surface of a photoconductor having a photoconductive layer provided on a conductive support is scanned at least along a main scanning direction of the photoconductor with a writing light beam having a wavelength of &lgr; &mgr;m and a spot diameter &phgr; &mgr;m to form an electrostatic latent image thereon. The surface of the photoconductor has such a roughness that the sectional curve thereof along the main scanning direction is represented by a function y=f(x) when the main scanning direction and the direction of the vertical height are assumed to be the X-axis and the Y-axis, respectively. The maximum height of the sectional curve in a region from an arbitral position x on the X-axis to a position (x+&phgr;) on the X-axis is at least &lgr;/2n &mgr;m where n is a refractive index of the photoconductive layer at the wavelength of the light beam.

Abstract: An electrophotographic photoreceptor including at least an electroconductive substrate, a photosensitive layer formed on the substrate and a protective layer formed on the photosensitive layer and including a binder resin, wherein when a solution in which the binder resin is dissolved in an organic solvent incompatible with water is mixed with deionized water having an electroconductivity not greater than 1 &mgr;S/cm and substantially the same weight as that of the solvent while agitating, the water has an electroconductivity not greater than 2 &mgr;S/cm.

Abstract: Electrophotographic photoreceptors having improved mechanical properties, electrical properties with excellent response characteristics are prepared by forming a photosensitive layer on an electroconductive substrate. The photosensitive layer contains a binder resin, which may be a polyarylate or a copolymer of polyarylate. The binder resin may be mixed with other resins up to 50 wt % with other resins to impove surface slip properties or fire retardant properties.

Abstract: The present invention relates to an organic photoreceptor unit that has a conductive base unit, a charge generating layer formed on the conductive base unit, a first charge transport layer that is formed on the charge generating layer and contains a first bonding resin and a first charge transport material, and a second charge transport layer that is formed on the first charge transport layer and contains a second bonding resin including denatured polycarbonate resin, fluorine resin particles and a second charge transport material, wherein the content of the second charge transport material relative to the second bonding resin is larger than the content of the first charge transport material relative to the first bonding resin.

Abstract: An electrophotographic photoconductor has an electroconductive support and a photoconductive layer which is formed thereon and contains at least one resin of a polyurethane resin, a polyester resin, or a polycarbonate resin, each resin having at least a structural unit of formula (1): wherein R1, R2, R3, a, b, and n are the same as those specified in the specification. An electrophotographic image forming apparatus and method, and a process cartridge employ the above photoconductor.

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 high-sensitivity and long-life electrophotographic photoreceptor comprising an electroconductive substrate and at least a photosensitive layer on the electroconductive substrate is provided, wherein the photosensitive layer contains a polyarylate resin not having a nitrogen atom in its repeating unit, and the Hall mobility at an electric field strength of 3×105 (V/cm) and at a temperature of 21° C. of the photosensitive layer is 3×10−6 (cm2/Vs) or more.

Abstract: A multi-active electrophotographic charge generation element comprises a conductive support, a charge generation layer (CGL) disposed on the conductive support, and a charge transport layer (CTL) disposed on the charge generation layer. The charge generation layer (CGL) includes a charge-generation material comprising an aggregated or crystalline form of a first dye or pigment and a first polymeric binder. The charge transport layer (CTL) comprises at least one charge-transport agent, a second dye or pigment having absorption in a selected spectral region that at least partially overlaps the absorption of a dissolved non-aggregated or non-crystalline form of the first dye or pigment, and a second polymeric binder. The second dye or pigment in the charge transport layer absorbs radiation in the selected spectral region that is incident on the charge transport layer, thereby shielding the charge generation layer from that radiation and mitigating visible radiation-induced photofatigue.