Abstract: A multi-layer electrophotographic photosensitive member contains a charge generating material including oxo-titanium phthalocyanine that among diffraction peaks for Bragg angles 2?±0.2° with respect to characteristic X-rays of CuK? having a wavelength of 1.542 ?, at least exhibits a highest diffraction peak at 27.2°. The multi-layer electrophotographic photosensitive member also contains a hole transport material including a triarylamine derivative shown in Generic Formula (1). A ratio of the hole transport material relative to a binder resin in a charge transport layer is no greater than 0.55. In Generic Formula (1), Ar1 represents an aryl group substituted with at least one substituent selected from the group consisting of an alkoxy group having two to four carbon atoms and an optionally substituted phenoxy group, and Ar2 represents an aryl group optionally substituted with an alkyl group having one to four carbon atoms.

Abstract: An electrophotographic photosensitive member includes a photosensitive layer that contains a charge generating material, a hole transport material, a binder resin, and a plasticizer. The hole transport material contains a triarylamine derivative represented by General Formula (1) below. The plasticizer contains at least one of a compound represented by General Formula (2a) and a compound represented by General Formula (2b) below.

Abstract: An electrophotographic photosensitive member includes a photosensitive layer. The photosensitive layer contains a charge generating material, a hole transport material, and a binder resin. The hole transport material contains an amine stilbene derivative represented by a general formula (1), and the binder resin contains a polycarbonate resin represented by a general formula (2).

Abstract: A multi-layered electrophotographic photosensitive member includes a multi-layered photosensitive layer. In the multi-layered photosensitive layer, a charge generating layer that contains a charge generating material and a charge transport layer that contains a charge transport material and a binder resin are layered sequentially. The binder resin includes a polycarbonate resin represented by a formula (1).

Abstract: The present invention is to provide a multilayer type electrophotographic photoconductor capable of stably obtaining a high image quality image over a long term by restraining the exposure memory and the photo memory, and an image forming apparatus comprising such a multilayer type electrophotographic photoconductor. A multilayer type electrophotographic photoconductor comprising a charge generating layer containing at least a charge generating agent on a base member directly or via an intermediate layer, and a charge transporting layer containing at least a charge transporting agent and a binder resin formed successively, wherein the light absorption degree at a 680 nm wavelength light beam in the photoconductive layer of the multilayer type electrophotographic photoconductor is of a value of 0.8 or less, and the light absorption degree at a 450 nm wavelength light beam is of a value of 1.

Abstract: The invention provides an oxo-titanylphthalocyanine crystal which is stable, is superior in dispersibility in a photoreceptive layer and efficiently contributes to improvements in sensitivity and charge retention rate of an electrophotographic photoreceptor when it is used as a charge generating agent, a method for producing the oxo-titanylphthalocyanine crystal, and an electrophotographic photoreceptor.

Abstract: In some embodiments, a drum unit may include an electrophotographic photosensitive member having a base member and a photosensitive layer on the base member. An embodiment may include a cleaning blade configured to abut the photosensitive layer to remove a developer remaining on the photosensitive layer of the electrophotographic photosensitive member. Some embodiments may include side seals disposed at both ends of the cleaning blade to inhibit leakage of the developer. In some embodiments, a portion of a side seal may be in contact with at least a portion of the surface and an end face of the photosensitive layer.

Abstract: The invention provides an oxo-titanylphthalocyanine crystal which is stable, is superior in dispersibility in a photoreceptive layer and efficiently contributes to improvements in sensitivity and charge retention rate of an electophotographic photoreceptor when it is used as a charge generating agent, a method for producing the oxo-titanylphthalocyanine crystal, and an electrophotographic photoreceptor the oxo-titanylphthalocyanine crystal has predetermined optical characteristics and thermal properties and is produced by a production method including the following steps (a) to (d): (a) a step of dissolving a crude oxo-titanylphthalocyanine crystal in an acid to obtain an oxo-titanylphthalocyanine solution; (b) a step of adding the oxo-titanylphthalocyanine solution dropwise in a poor solvent to obtain a wet cake; (c) a step of washing the wet cake with an alcohol having 1 to 4 carbon atoms; and (d) a step of stirring the washed wet cake under heating in a nonaqueous solvent to obtain an oxo-titanylphthalocya

Abstract: The invention provides an oxo-titanylphthalocyanine crystal which is stable, is superior in dispersibility in a photoreceptive layer and efficiently contributes to improvements in sensitivity and charge retention rate of an electrophotographic photoreceptor when it is used as a charge generating agent, a method for producing the oxo-titanylphthalocyanine crystal, and an electrophotographic photoreceptor.

Abstract: The invention provides an oxo-titanylphthalocyanine crystal which is stable, is superior in dispersibility in a photoreceptive layer and efficiently contributes to improvements in sensitivity and charge retention rate of an electrophotographic photoreceptor when it is used as a charge generating agent, a method for producing the oxo-titanylphthalocyanine crystal, and an electrophotographic photoreceptor.

Abstract: According to the present invention, a titanyl phthalocyanin crystal excellent in storage stability in organic solvents, a method for preparing the same and an electrophotographic photoconductor using the same are provided. In the titanyl phthalocyanin crystal, the method for preparing such a titanyl phthalocyanin crystal and the electrophotographic photoconductor using the same, the titanyl phthalocyanin crystal is characterized by having the maximum peak at a Bragg angle 2?±0.2°=27.2° in a CuK? characteristic X-ray diffraction spectrum and one peak within the range of 270 to 400° C. other than a peak accompanied by the vaporization of adsorbed water in a differential scanning calorimetric analysis.

Abstract: In some embodiments, a drum unit may include an electrophotographic photosensitive member having a base member and a photosensitive layer on the base member. An embodiment may include a cleaning blade configured to abut the photosensitive layer to remove a developer remaining on the photosensitive layer of the electrophotographic photosensitive member. Some embodiments may include side seals disposed at both ends of the cleaning blade to inhibit leakage of the developer. In some embodiments, a portion of a side seal may be in contact with at least a portion of the surface and an end face of the photosensitive layer.

Abstract: Disclosed is an image forming apparatus composed of a combination of multi-layered electrophotographic photoreceptor wherein an undercoat layer is made of at least fine titanium oxide particles and a binder resin and has a thickness of 3 ?m or less and the fine titanium oxide particles are surface treated with alumina and silica and have a number average primary particle size of 20 nm or less, and exposing means by LED exposure. Thus, an electrophotographic photoreceptor having good balance between dispersibility of titanium oxide and electrical insulation properties is obtained and image fog does not occur under high temperature and high humidity environment and also excellent image quality can be maintained during continuous printing under low temperature and low humidity environment.

Abstract: According to the present invention, a titanyl phthalocyanin crystal excellent in storage stability in organic solvents, a method for preparing the same and an electrophotographic photoconductor using the same are provided. In the titanyl phthalocyanin crystal, the method for preparing such a titanyl phthalocyanin crystal and the electrophotographic photoconductor using the same, the titanyl phthalocyanin crystal is characterized by having the maximum peak at a Bragg angle 2 ?±0.2°=27.2° in a CuK? characteristic X-ray diffraction spectrum and one peak within the range of 270 to 400° C. other than a peak accompanied by the vaporization of adsorbed water in a differential scanning calorimetric analysis.

Abstract: It is an object of the present invention to provide a wet-developing electrophotographic photoconductor which can be manufactured stably by making use of particular physical property indexes of an electron transport agent and a binding resin and possesses the excellent durability and the excellent solvent resistance and a wet-developing image forming device which uses such a wet-developing electrophotographic photoconductor. To achieve such an object, in a wet-developing electrophotographic photoconductor which forms a photosensitive layer containing at least a charge generating agent, an electron transport agent, a hole transport agent and a binding resin on an electrically conductive base body thereof and a wet-developing image forming device which uses the wet-developing electrophotographic photoconductor, an inorganic value/organic value (I/O value) of the electron transport agent is set to 0.60 or more and an inorganic value/organic value (I/O value) of the binding resin is set to 0.

Abstract: An electrophotographic photoconductor where generation of cracks, crystallization of a photosensitive layer, and the like occur infrequently by sticking of finger oil. An electrophotographic photoconductor includes a conductive substrate on which a photosensitive layer containing at least a charge generating agent, a hole transfer agent and a binding resin is provided, wherein the binding resin is comprised of a plurality of polycarbonate resins; and the photosensitive layer contains a biphenyl derivative as a plasticizer component represented by the following general formula (1). (wherein R1 to R10 each independently represent a substituted or unsubstituted alkyl group having 1 to 12 carbon atoms, and R represents a substituted or unsubstituted aryl group having 1 to 12 carbon atoms or a substituted or unsubstituted alkylene group having 1 to 12 carbon atoms).

Abstract: To provide an electrophotographic photoconductor which can effectively prevent the generation of exposure memory and the increase in residual potential by easily adjusting the electroconductivity in an intermediate layer, and an image forming apparatus using the electrophotographic photoconductor. An electrophotographic photoconductor comprising a base body, and an intermediate layer containing a titanium oxide and a binding resin and a photosensitive layer which are arranged on the base body, and an image forming apparatus using the same, wherein an average primary particle diameter of the titanium oxide is set to a value within the range of 5 to 30 nm, a thickness of the intermediate layer set to a value within the range of 0.5 to 3 ?m, and the volume resistivity in the intermediate layer is set to a value within the range of 1×1010 to 5×1013 ?·cm.

Abstract: The invention provides an oxo-titanylphthalocyanine crystal which is stable, is superior in dispersibility in a photoreceptive layer and efficiently contributes to improvements in sensitivity and charge retention rate of an electrophotographic photoreceptor when it is used as a charge generating agent, a method for producing the oxo-titanylphthalocyanine crystal, and an electrophotographic photoreceptor.

Abstract: The present invention is to provide a multilayer type electrophotographic photoconductor capable of stably obtaining a high image quality image over a long term by restraining the exposure memory and the photo memory, and an image forming apparatus comprising such a multilayer type electrophotographic photoconductor. A multilayer type electrophotographic photoconductor comprising a charge generating layer containing at least a charge generating agent on a base member directly or via an intermediate layer, and a charge transporting layer containing at least a charge transporting agent and a binder resin formed successively, wherein the light absorption degree at a 680 nm wavelength light beam in the photoconductive layer of the multilayer type electrophotographic photoconductor is of a value of 0.8 or less, and the light absorption degree at a 450 nm wavelength light beam is of a value of 1.

Abstract: Disclosed is an image forming apparatus composed of a combination of multi-layered electrophotographic photoreceptor wherein an undercoat layer is made of at least fine titanium oxide particles and a binder resin and has a thickness of 3 ?m or less and the fine titanium oxide particles are surface treated with alumina and silica and have a number average primary particle size of 20 nm or less, and exposing means by LED exposure. Thus, an electrophotographic photoreceptor having good balance between dispersibility of titanium oxide and electrical insulation properties is obtained and image fog does not occur under high temperature and high humidity environment and also excellent image quality can be maintained during continuous printing under low temperature and low humidity environment.