Abstract: An electrophotosensitive material of the present invention is formed by providing a photosensitive layer containing a bis-azo pigment expressed in formula (1): ##STR1## wherein A.sup.1, A.sup.2, R.sup.1 and n are as defined, as a charge generating material, and a diamine compound expressed in formula (2): ##STR2## wherein R.sup.2, R.sup.3, R.sup.4, R.sup.5, R.sup.6 and R.sup.7 p and q k, l, m and o are as defined, as a charge-trasferring material, on a conductive substrate. As a charge generating material, a perylene pigment, anthanthrone pigment, X-type metal-free phthalocyanine pigment, imidazoleperylene pigment or perylene bis-azo pigment are preferable used together with the bis-azo pigment. Thus, photosensitive material is excellent in sensitivity and durability.

Abstract: In accordance with the present invention, there is provided a phenanthrylenediamine derivative represented by the general formula (1). The derivative is excellent in the electric charge transferring capability, the compatibility with a binding resin and the stability, thereby providing a photosensitive material which is highly sensitive and excellent in the durability. ##STR1## ?wherein R.sup.1, R.sup.2, R.sup.3 and R.sup.4 each represent a halogen atom, an alkyl group, an alkoxy group or an aryl group; and a, b, c and d each represent an integer from 0 to 5!.

Abstract: The present invention provides a novel naphthylenediamine derivative which is superior in electric charge transferring capability, compatibility with binding resin and stability, and an electrophotosensitive material which has a higher sensitivity and an excellent durability. The above naphthylenediamine derivative is represented by the following general formula (1), and the electrophotosensitive material is formed by providing a photosensitive layer having this naphthylenediamine derivative as an electric charge transferring material on a conductive substrate. ##STR1## wherein R.sup.1 to R.sup.4, R.sup.5a to R.sup.5f and a to d are as defined.

Abstract: The present invention provides a tryptoanthrinimine derivative represented by the general formula (Y): ##STR1## wherein R.sup.A to R.sup.M are as defined. Such a derivative of the general formula (Y) is superior in electron transferring capability. Accordingly, an electrophotosensitive material comprising a photosensitive layer containing this derivative (Y) is superior in sensitivity.

Abstract: An electrophotosensitive material of the present invention is formed by providing a photosensitive layer containing a bis-azo pigment expressed in formula (1): ##STR1## wherein A.sup.1, A.sup.2, R.sup.1 and n are as defined, as a charge generating material, and a diamine compound expressed in formula (2): ##STR2## wherein R.sup.2, R.sup.3, R.sup.4, R.sup.5, R.sup.6 and R.sup.7 p and q k, l, m and o are as defined, as a charge-trasferring material, on a conductive substrate. As a charge generating material, a perylene pigment, anthanthrone pigment, X-type metal-free phthalocyanine pigment, imidazoleperylene pigment or perylene bis-azo pigment are preferable used together with the bis-azo pigment. Thus, photosensitive material is excellent in sensitivity and durability.

Abstract: The present invention provides a process for packing a drum-shaped electrophotographic photoreceptor comprising the steps of folding a wrapping-start edge portion of a light-shielding packing sheet outwardly in a diametrical direction of the photoreceptor across a width of the packing sheet, and wrapping the packing sheet on a circumferential surface of the photoreceptor. The packing process of the present invention enables an electrophotographic photoreceptor, which has a small diameter, or has a soft surface and is susceptible to scratching, to be packed without forming scratches on its surface and decreasing its photosensitivity.

Abstract: An azo compound represented by the following general formula IA and an electrophotographic photosensitive member comprising a photosensitive layer containing the azo compound: ##STR1## wherein R.sup.1 and R.sup.2 are the same or different from each other and indicate a hydrogen atom, an alkyl group, an alkenyl group, a hydroxyl group, an alkoxy group, a carboxy group, an alkoxy carbonyl group, an acyl group, an aryl group, a halogen group or a cyano group, respectively; R.sup.14 indicates a hydrogen atom, a halogen group, an alkyl group, an alkoxy group, an aryl group, an amine group, a cyano group, a nitro group or a sulfoxide group; and A indicates a coupler residue having an acceptor property.

Abstract: An azo compound represented by the following general formula IA and an electrophotographic photosensitive member comprising a photosensitive layer containing the azo compound: ##STR1## wherein R.sup.1 and R.sup.2 are the same or different from each other and indicate a hydrogen atom, an alkyl group, an alkenyl group, a hydroxyl group, an alkoxy group, a carboxy group, an alkoxy carbonyl group, an acyl group, an aryl group, a halogen group or a cyano group, respectively; R.sup.14 indicates a hydrogen atom, a halogen group, an alkyl group, an alkoxy group, an aryl group, an amino group, a cyano group, a nitro group or a sulfoxide group; and A indicates a coupler residue having an acceptor property.

Abstract: An azo compound represented by the following general formula IA and an electrophotographic photosensitive member comprising a photosensitive layer containing the azo compound: ##STR1## wherein R.sup.1 and R.sup.2 are the same or different from each other and indicate a hydrogen atom, an alkyl group, an alkenyl group, a hydroxyl group, an alkoxy group, a carboxy group, an alkoxy carbonyl group, an acyl group, an aryl group, a halogen group or a cyano group, respectively; R.sup.14 indicates a hydrogen atom, a halogen group, an alkyl group, an alkoxy group, an aryl group, an amino group, a cyano group, a nitro group or a sulfoxide group; and A indicates a coupler residue having an acceptor property.

Abstract: The present invention provides a benzidine derivative of the following general formula (1). This derivative is excellent in photostability. Accordingly, when this derivative is contained in a photosensitive layer as an electric charge transferring material, there may be obtained an electrophotosensitive material excellent in photostability.

Abstract: The present invention provides a hydrazone compound represented by the following general formula (1). This compound has higher hole mobility as compared with an electric charge transferring material such as the conventional hydrazone compound or the like. Accordingly, when this compound is contained in a photosensitive layer as the electric charge transferring material, there may be obtained an electrophotosensitive material excellent in sensitivity, charging ability and repeat characteristics. ##STR1## (wherein R.sup.1, R.sup.2, R.sup.3, R.sup.4 and R.sup.5 are the same as or different from one another, and each is a hydrogen atom, a halogen atom, an alkyl group or an alkoxy group.

Abstract: The present invention provides a hydrazone compound represented by the following general formula (1). This compound has higher hole mobility as compared with an electric charge transferring material such as the conventional hydrazone compound or the like. Accordingly, when this compound is contained in a photosensitive layer as the electric charge transferring material, there may be obtained an electrophotosensitive material excellent in sensitivity, charging ability and repeat characteristics. ##STR1## (wherein R.sup.1 is a hydrogen atom, a halogen atom, an alkyl group or an alkoxy group, and R.sup.2 is a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group or the following group.

Abstract: The present invention provides a hydrazone compound of the following general formula (I). This compound presents a higher hole mobility as compared with a conventional electric charge transferring material such as a conventional hydrazone compound or the like. Accordingly, when a photosensitive layer contains, as the electric charge transferring material, the hydrazone compound of the present invention, there can be obtained an electrophotosensitive material which is excellent in sensitivity and charging ability and has high repeating characteristics. ##STR1## (wherein R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5 and R.sup.6 may be same as or different from one another, and each is a hydrogen atom, an alkyl group, an alkoxy group, an aralkyl group or an aryl group, each of said alkyl, alkoxy, aralkyl and aryl groups may have a substituent group; A.sup.1, A.sup.2, A.sup.3, A.sup.4, A.sup.5 and A.sup.

Abstract: The present invention provides a phenylenediamine derivative of the following general formula (1). This derivative is excellent in photostability. Accordingly, when this derivative is contained in a photosensitive layer as an electric charge transferring material, there may be obtained an electrophotosensitive material excellent in photostability. ##STR1## [wherein R.sup.1, R.sup.2, R.sup.3, R.sup.4 and R.sup.5 are the same as or different from one another.Each of A.sup.1 and A.sup.2 is a hydrogen atom or the following group: ##STR2## (wherein R.sup.6 and R.sup.7 are the same as or different from each other, and each is a hydrogen atom, an alkyl group, an alkoxy group, an aryl group, an aralkyl group or a heterocyclic group; the alkyl group, the alkoxy group, the aryl group, the aralkyl group and the heterocyclic group may have respective substituting groups; n is 0 or 1. A.sup.1 and A.sup.2 are not hydrogen atoms simultaneously. R.sup.6 and R.sup.7 are not hydrogen atoms simultaneously.

Abstract: An electrophotographic photosensitive element having a layer containing polyvinyl acetal, wherein the layer is formed by coating a coating composition containing the polyvinyl acetal and being compounded with a solution comprising an acetylacetone complex salt, an alcohol and water, and a process of producing an electrophotographic photosensitive element having a layer containing polyvinyl acetal, wherein the layer is provided by the steps of:preparing (A) a solution of an acetylacetone complex salt dissolved in a mixed solvent of an alcohol and water, and (B) a solution containing polyvinyl acetal;mixing the solutions (A) and (B) to provide a coating composition (C);coating the coating composition (C) on a constituting layer or a conductive substrate; and drying.

Abstract: This invention presents an electrophotographic photosensitive material wherein a charge transporting layer and a charge generating layer are laminated in this order on a conductive substrate, and the charge generating layer contains N-type dye and P-type dye at a ratio of 40/60 to 90/10 (N-type dye/P-type dye) by weight.This electrophotographic photosensitive material is especially superior in reproductivity of red-colored originals as well as having a high sensitivity.

Abstract: Disclosed is an electrophotographic photosensitive material containing in a photosensitive layer an m-phenylenediamine compound represented by the following general formula [I]: ##STR1## wherein R.sup.5, R.sup.6, R.sup.7 and R.sup.8 are groups substituted at meta-positions to the nitrogen atoms and represent a hydrogen atom, an alkyl group, an alkoxyl group or a halogen atom, with the proviso that at least two of R.sup.5, R.sup.6, R.sup.7 and R.sup.8 represent an alkyl group, alkoxyl group or a halogen atom, and R represents a hydrogen atom, an alkyl group, an alkoxyl group or a halogen atom.This meta-substituted m-phenylenediamine compound of general formula [I] is hardly crystallized in a resin but is sufficiently dissolved in the resin, and therefore, the concentration of the compound in the resin can be increased and the mobility can be enhanced. Accordingly, an electrophotographic photosensitive material having an increased sensitivity can be provided.

Abstract: An electrophotographic sensitive material is provided which has a photosensitive layer formed on an electroconductive substrate, the photosensitive layer containing a pyrrolopyrrole type compound represented by the following genral formula (1) and a benzidine derivative represented by the following general formula (2) ##STR1## In the general formulas (1) and (2), R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5, R.sup.6, R.sup.7, R.sup.8, R.sup.9, R.sup.10, l, m, n, o, p and q have the same meanings as defined in the text of the specification.