Abstract: There is provided an organic photoconductive material that can realize an electrophotographic photoreceptor which is not only excellent in charge transporting ability but also excellent in solubility in a solvent and compatibility with a resin and moreover, which is excellent in both electric properties and durability, and the organic photoconductive material that is useful also as a raw material compound for various types of functional materials. An asymmetric bis-hydroxyenamine compound represented by the following structural formula (1aa) is provided. The compound is allowed to be contained in a charge transporting layer or a surface protective layer of an electrophotographic photoreceptor. This leads realization of the electrophotographic photoreceptor which is excellent in electric properties and durability and can stably form an image of high quality being free of an image defect such as a black spot.

Abstract: An object of the invention is to provide an electrophotographic photoreceptor showing high responsivity even under a low temperature and low humidity circumstance and capable of compatibilize the decrease of the size and the increase in the image forming speed of an electrophotographic apparatus. In a photosensitive layer of an electrophotographic photoreceptor, oxotitanium phthalocyanine having a crystal form showing a diffraction peak at a Bragg angle 2?(error: 2?±0.2°) of 27.2° in an X-ray diffraction spectrum is contained as a charge generating substance, and an enamine compound represented by the general formula for example, the structural formula (1-1) is contained as a charge transporting substance. Accordingly, the electrophotographic photoreceptor showing high responsivity even under a low temperature and low humidity circumstance is realized.

Abstract: An object of the invention is to provide a highly reliable electrophotographic photoreceptor having high sensitivity, excellent in light responsivity, not suffering from lowering of such characteristics even when it is used under a low temperature circumstance or in a high speed electrophotographic process, and with less fatigue degradation upon repetitive use. In a photosensitive layer of an electrophotoreceptor, an enamine compound represented by the following general formula (1), for example, the following structural formula is contained as a charge transporting substance, and further at least one of an antioxidant and a light stabilizer is contained. Accordingly, an electrophotographic photoreceptor excellent in sensitivity and light responsivity in various environments, and with less fatigue degradation upon repetitive use is realized.

Abstract: According to the present invention, an enamine compound having a specific structure is used as an organic photoconductive material. This enamine compound is obtained based on asymmetrical secondary naphtylamine which is readily available at a lowest price, by introducing phenyl groups containing substituents, as constituents units of the enamine part and presents excellent compatibility with binder resins, will not present detrimental effects such as partial crystallization at film forming and have a high charge mobility. The compound is able to realize highly reliable electrophotographic photoreceptor and an image forming apparatus which present a high electrostatic potential, high sensitivity and high enough light response and are excellent in durability and will not degrade in these characteristics under a low-temperature environment or in a high-speed process and will not lower in these characteristics even due to exposure to light.

Abstract: A method of forming an electrophotographic photoreceptor capable of forming a smooth coating film free of pinholes, bubbles, surface unevenness, etc. in a short time as a coating film for forming a photosensitive layer is provided. The method includes heating and drying a coating film formed by coating a coating solution containing ingredients of the photosensitive layer and a solvent medium containing 30% by weight or more of a solvent having a relative evaporation rate of less than 1.7 represented by the following formula (1) in an air stream at a temperature of 50° C. or higher and 130° C.

Abstract: A hydrazone compound capable of realizing an electrophotographic photoreceptor having good electric properties such as good sensitivity and light responsibility, good electric and mechanical durability and good environment stability, is provided. The hydrazone compound is represented by the following general formula (1). The compound is contained in the charge transporting layer of the electrophotographic photoreceptor.

Abstract: A method for producing a high-quality and low-cost laminate type electrophotographic photoreceptor having a coating film of uniform thickness with high efficiency is provided. In the electrophotographic photoreceptor having a laminated structure composed at least of two layers: a charge generating layer containing a charge generating substance and a charge transporting layer containing a charge transporting substance, the charge generating layer is formed by applying a coating solution for forming the charge generating layer onto the conductive supportby an ink-jet coating method, and the charge transporting layer is formed by applying a coating solution for forming the charge transporting layer onto the charge generating layer by a roll coating method.

Abstract: An amine compound represented by the following general formula (1) is incorporated as a charge-transporting substance into a charge-transporting layer of an electrophotographic photoreceptor.

Abstract: An amine compound represented by the general formula (1), which is incorporated as a charge-transporting substance to a charge-transporting layer of an electrophotographic photoreceptor: (in which Ar1, Ar2 and Ar3 each represents an optionally-substituted aryl group, or an optionally-substituted monovalent heterocyclic ring residue. Ar4 represents an optionally-substituted arylene group, or an optionally-substituted bivalent heterocyclic ring residue. R1 represents an optionally-substituted alkyl group, an optionally-substituted aryl group, an optionally-substituted monovalent heterocyclic ring residue, or an optionally-substituted aralkyl group. R2 and R3 each represents a hydrogen atom, an optionally-substituted alkyl group, an optionally-substituted aryl group, an optionally-substituted monovalent heterocyclic ring residue, or an optionally-substituted aralkyl group. n represents an integer of 1 or 2.

Abstract: An image forming apparatus having excellent chargeability, sensitivity and light responsivity of an electrophotographic photoconductor and capable of forming images of high quality and high resolution at a high speed in various circumstances, is provided. An electrophotographic photoconductor having a photosensitive layer containing the enamine compound represented by the following general formula (1), for example, the enamine compound represented by the following structural formula (1-1) as a charge transportation substance is mounted to an image forming apparatus and the volume average particle size of the toner contained in a developer 50 housed in a developing device 33 is set to a size from 4 to 7 ?m.

Abstract: An electrophotographic photoreceptor of excellent durability having high sensitivity and light responsiveness, not suffering from lowering of the electric characteristics by exposure to light, change of circumstance, or repetitive use, and excellent in the cleaning property and not suffering from lowering of the picture quality of formed images for a long times, in which an enamine compound represented by the general formula (1), for example, an enamine compound represented by the following structural formula (1-1) is incorporated in a photosensitive layer 14, and the surface energy (?) on the surface of the photosensitive layer 14 is set to 20.0 mN/m or more and 35.

Abstract: To suppress generation of a joint when detaching an applicator roll and cylindrical substrate from each other in a simple control to form a coating film having a uniform thickness efficiently on the cylindrical substrate is provided. A coating liquid is supplied from a pan to an applicator roll via a metalling roll, the applicator roll supplied with the coating liquid and a cylindrical substrate provided so as to be close to or in contact with the applicator roll are rotated. The coating liquid is transferred from the applicator roll to the cylindrical substrate, and the cylindrical substrate is rotated in a predetermined number. Thereafter, such control is carried out that the circumferential speed V1 of one of the applicator roll and the cylindrical substrate is higher than the circumferential speed V2 of the other when detaching the applicator roll and the cylindrical substrate from each other.

Abstract: The invention is to provide an organic photoconductive material capable of realizing electrophotographic photoreceptors of high reliability that have high charge potential, high sensitivity, good responsiveness to light and good durability, of which the characteristics do not lower even when they are driven at low temperatures or at high speed and even when they are exposed to light, and to provide an electrophotographic photoreceptor that comprises the material and an image-forming apparatus. An organic photoconductive material of the following general formula (1), for example, an enamine compound of the following structural formula (1-1) is produced. Using the organic photoconductive material for the charge-transporting substance to be in a photosensitive layer on a conductive support, an electrophotographic photoreceptor is fabricated, and this is mounted on an image-forming apparatus.

Abstract: An object of the invention is to obtain an electrophotographic photoreceptor having high sensitivity, high image quality, high stability and high resolution. A charge generating layer of the electrophotographic photoreceptor contains, as a charge generating substance, a crystalline titanyl phthalocyanine composition exhibiting, in an X-ray diffraction spectrum of a CuK&agr; characteristic X-ray (wavelength: 1.5418 Å), at least four diffraction peaks at Bragg angles (2&thgr;±0.2°) of 10.0° or lower, and a diffraction peak at a Bragg angle of 27.2° having an intensity smaller than the maximum diffraction intensity of the four diffraction peaks, or a lowly crystalline titanyl phthalocyanine composition exhibiting a diffraction peak having the maximum diffraction intensity at a Bragg angle (2&thgr;±0.2°) of 27.3°. A charge transporting layer of the electrophotographic photoreceptor contains, as a charge transporting substance, a bisamine compound.

Abstract: An object of the invention is to improve the photosensitivity characteristics, characteristics on repeated use and stability of a photoreceptor. A photosensitive layer formed on a conductive support of a photoreceptor contains crystalline oxotitanylphthalocyanine having major peaks in an X-ray diffraction spectrum at Bragg angles (2&thgr;±0.2°) of 7.3°, 9.4°, 9.6°, 11.6°, 13.3°, 17,9°, 24.1° and 27.2°, wherein a peak bundle formed by overlapping the peaks at 9.4° and 9.6° is the largest peak, and the peak at 27.2° is the secondary largest peak as a charge generating substance. Furthermore, it contains a bisamine compound, an N,N′-bisenamine compound, a styryl compound, an amine-hydrazone compound, a benzofuran-bishydrazone compound, a bisenamine compound, a benzofuran-bishydrazone compound or a benzofuran-bis-cyclic hydrazone compound represented by the particular structural formulae as a charge transporting substance.

Abstract: A photoelectric material having high efficiency and superior durability is provided. The photoelectric material includes a semiconductor and a photosensitizing dye attached to the semiconductor, wherein the dye is a phthalocyanine derivative, a dioxazine derivative or an indigo derivative having at least one interlocking group and at least one hydrophobic group selected from the group consisting of monovalent substituted and unsubstituted aliphatic hydrocarbon groups and monovalent substituted and unsubstituted alicyclic hydrocarbon groups. The hydrophobic group is preferably an alkyl group with 3 to 12 carbon atoms. The interlocking group is a carboxyl group, a sulfonic acid group, phosphono group or the like. In manufacturing the photoelectric material, the dye is dissolved in a hydrophobic and/or aprotic solvent. In order to attach the dye to the semiconductor, the semiconductor is dipped in the dye solution.

Abstract: A photoreceptor for electrophotography of the present invention includes a photosensitive layer provided on a conductive support, the photosensitive layer containing a bishydrazone compound represented by the following general formula (Ia): ##STR1## where: R.sup.1 and R.sup.2 each represent a substituted or unsubstituted aryl group, a substituted or unsubstituted aralkyl group, a heterocyclic group, or an alkyl group which has 1 to 4 carbon atoms;"a" represents an alkyl group which has 1 to 3 carbon atoms, an alkoxy group which has 1 to 3 carbon atoms, a dialkylamino group which has 1 to 3 carbon atoms, a halogen atom, or a hydrogen atom; andn represents an integer of 1 to 3, wherein, if n is 2 or greater, a plurality of "a" substituents may be identical to or different from one another, or the substituents may form a ring.