Abstract: A photoreceptor including an electroconductive substrate; a photosensitive layer on the electroconductive substrate; and a protection layer on the photosensitive layer, wherein the protection layer includes a radical polymerizable compound having three or more radical polymerizable groups without a charge transportable group, a monofunctional radical polymerizable compound having a specific charge transportable group and a non-radical polymerizable compound having a specific charge transportable group.

Abstract: An electrophotographic photoreceptor including an electroconductive substrate; a photosensitive layer located overlying the electroconductive substrate; and an outermost layer located overlying the photosensitive layer, wherein the outermost layer includes filler and a crosslinked resin having a residual group of a polycarboxylic acid compound and a group having the following formula (1): wherein each of R5 and R6 independently represents a hydrogen atom, or a substituted or unsubstituted alkyl group having 1 to 3 carbon atoms.

Abstract: An image forming apparatus including a latent image bearing member, a charging device, a latent electrostatic image formation device, a development device, a transfer device, and a lubricant supplying device, the latent image bearing member satisfying (I), (II) and (III): |(A1?B1)?(A2?B2)|?5.0??(I) B1?1 (atomic %)??(II) 1 (nm)?X?30 (nm)??(III), where, by XPS analysis, A1 and B1 represent oxygen and silicon atom content ratio in a cross-linked surface layer, respectively, A2 represents oxygen atom content ratio in a surface dug through a cross-linked surface layer along a direction perpendicular to the latent image bearing member surface, to an electroconductive substrate at depth point X where B1 decreases to not greater than B1×0.5, and B2 represents the silicone atom content ratio in the surface at X.

Abstract: An electrophotographic photoreceptor including an electroconductive substrate; a charge generation layer located overlying the electroconductive substrate; a charge transport layer located overlying the charge generation layer; and an outermost layer located overlying the charge transport layer. The charge transport layer includes a positive hole transport material having the following formula (1): wherein each of R1 to R26 independently represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or an alkoxyl group having 1 to 4 carbon atoms, and a compound having the following formula (2): wherein each of R27 and R28 independently represents a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group.

Abstract: A degradation level estimating device for estimating degradation level of a photoreceptor of an image forming apparatus performing at least a charging process, an optical image writing process, a developing process, and a transferring process in which a toner image on the photoreceptor is transferred onto a receiver while applying a charge to the photoreceptor. The degradation level estimating device includes a charge dependence detector to detect charge quantity dependence of a charge property of the photoreceptor in the charging process on the quantity of the charge applied to the photoreceptor in the last transferring process by subjecting the photoreceptor to the processes plural times without performing the optical image writing process, followed by the charging process, while changing the quantity of the charge and measuring the charge property of the photoreceptor. The degradation level estimating device estimates the degradation level of the photoreceptor based on the charge quantity dependence.

Abstract: An image forming apparatus having an image bearing member, a charger to charge the surface of the image bearing member, an irradiator to irradiate the image bearing member to form the latent image, a developing device to develop the latent electrostatic image with toner to obtain a visible image, a transfer device to transfer the visible image to a transfer medium by a transfer bias applied to a transfer area between the image bearing member and the transfer member, and a voltage detector to measure a first surface voltage and a second surface voltage under different conditions, and a life expectancy identification device to identify whether or when the expected working life of the image bearing member has come to the end based on a comparison of the first surface voltage and the second surface voltage.

Abstract: An image bearing member having an electroconductive substrate, a photosensitive layer overlying the electroconductive layer, and a cross-linked surface layer overlying the photosensitive layer, which contains a cross-linked polymer and a first compound consisting essentially of a nitrogen atom and a phenyl group, biphenyl group, and condensed polycyclic hydrocarbon group, or a second compound consisting essentially of a nitrogen atom and hydrogen atoms, halogen atoms, alkyl groups, alkoxy groups, or aryl groups, substituted or non-substituted alkyl groups, substituted or non-substituted alkoxy groups, substituted or non-substituted aralkyl groups, substituted or non-substituted aryl group, substituted or non-substituted alkylene groups, cyano groups, nitro groups, or —OCO?CH2R16, in which R16 represents a hydrogen atom, a substituted or non-substituted alkyl group, a substituted or non-substituted alkoxy group, or a substituted or non-substituted aryl group.

Abstract: A photoreceptor including an electroconductive substrate; a photosensitive layer located overlying the electroconductive substrate; and a crosslinked outermost layer located overlying the photosensitive layer and including a crosslinked material and a specific carbazole compound serving as a charge transport material. An image forming apparatus including the photoreceptor; a charger to charge the photoreceptor; an irradiator to irradiate the charged photoreceptor to form an electrostatic latent image thereon; a developing device to develop the electrostatic latent image with a developer including a toner to form a toner image on the photoreceptor; and a transferring device to transfer the toner image onto a recording material.

Abstract: A lubricant for use in an image forming apparatus, which contains a lubricant material and at least one of diamine compounds represented by chemical structure 1, 2, and 3, where R1 and R2 independently represent an alkyl group optionally having a substitution group and an aromatic hydrocarbon group optionally having a substitution group, one of R1 and R2 is an aromatic hydrocarbon group optionally having a substitution group, R1 and R2 optionally share bond connectivity to form a heterocyclic ring containing a nitrogen atom, and Ar represents an aromatic hydrocarbon group optionally having a substitution group, where R3 and R4 independently represent an alkyl group having one to four carbon atoms optionally substituted by an aromatic hydrocarbon group, R3 and R4 optionally share bond connectivity to form a heterocyclic ring containing a nitrogen atom, Ar1 and Ar2 independently represent a substituted or a non-substituted aromatic ring group, l and m each, independently, represent an integer of

Abstract: An image forming apparatus including a latent image bearing member, a charging device, a latent electrostatic image formation device, a development device, a transfer device, and a lubricant supplying device, the latent image bearing member satisfying (I), (II) and (III): |(A1?B1)?(A2?B2)|?5.0??(I) B1?1 (atomic %)??(II) 1 (nm)?X?30 (nm)??(III), where, by XPS analysis, A1 and B1 represent oxygen and silicon atom content ratio in a cross-linked surface layer, respectively, A2 represents oxygen atom content ratio in a surface dug through a cross-linked surface layer along a direction perpendicular to the latent image bearing member surface, to an electroconductive substrate at depth point X where B1 decreases to not greater than B1×0.5, and B2 represents the silicone atom content ratio in the surface at X.