Abstract: There is provided an electrophotographic photoreceptor including: a conductive support; and a photosensitive layer and a protective layer containing a cured product obtained by curing a curable compound, which are sequentially disposed on the conductive support. An area ratio A/B is 0.0045 or less, where A is an absorbance area at a wavelength of 1647 cm?1 to 1627 cm?1 and B is an absorbance area of a peak at a wavelength of 1800 cm?1 to 1647 cm?1 in an infrared absorption spectrum measurement of the protective layer. The photosensitive layer contains at least a hole transport material (HTM) and a radical acceptor compound. The electrophotographic photoreceptor is an electrophotographic photoreceptor including a protective layer with a high curing degree and having good initial electrical characteristics, excellent strong exposure characteristics, and excellent transfer repeatability.

Abstract: The object of the present invention is to provide a positive charging electrophotographic photoreceptor having high sensitivity, low residual potential, and excellent chargeability, and relates to a positive charging electrophotographic photoreceptor including a conductive support, a photosensitive layer, and a protective layer in this order, the photosensitive layer containing a charge generation substance, a positive hole transport substance, and an electron transport substance in the same layer, in which the positive hole transport substance includes at least one of the compounds represented by any one of the following formulas (1) to (5), and a binder resin of the protective layer is an alcohol-soluble thermoplastic resin, providing that the symbols in the formula are defined in the specification.

Abstract: An electrophotographic photoreceptor that includes a conductive support; and at least a charge generation layer and a charge transport layer on the conductive support, where the charge transport layer includes at least two layers of a first charge transport layer which is an outermost layer and a second charge transport layer which is in contact with the first charge transport layer, such that the elastic deformation ratio of a binder resin A contained in the first charge transport layer is T1(%) and the elastic deformation ratio of a binder resin B contained in the second charge transport layer is T2(%) such that T1 and T2 satisfy a relationship of {0?(T1?T2)?4}, the first charge transport layer contains a charge transport material ? having a molecular weight of 600 or more, and the binder resin A and the binder resin B have different monomer units from each other.

Abstract: The object of the present invention is to provide a positive charging electrophotographic photoreceptor having high sensitivity, low residual potential, and excellent chargeability, and relates to a positive charging electrophotographic photoreceptor including a conductive support, a photosensitive layer, and a protective layer in this order, the photosensitive layer containing a charge generation substance, a positive hole transport substance, and an electron transport substance in the same layer, in which the positive hole transport substance includes at least one of the compounds represented by any one of the following formulas (1) to (5), and a binder resin of the protective layer is an alcohol-soluble thermoplastic resin, providing that the symbols in the formula are defined in the specification.

Abstract: The present invention aims to provide an electrophotographic photoreceptor including a charge transport layer and being excellent in electrical properties and adhesiveness while exhibiting sufficient abrasion resistance indispensable for prolonging the life, and an electrophotographic photoreceptor cartridge and an image forming apparatus including the electrophotographic photoreceptor, which is an electrophotographic photoreceptor including a charge transport layer including at least two layers, wherein an elastic deformation ratio of a binder resin contained in a first charge transport layer which is an outermost layer and an elastic deformation ratio of a binder resin contained in a second charge transport layer satisfy a predetermined relationship.

Abstract: An electrophotographic photoreceptor comprises a conductive support and, at least a photosensitive layer on the conductive support, wherein the photosensitive layer includes a polyarylate resin and the polyarylate resin has a repeating structure represented by formula (1), and the amount of bisphenol residues represented by formula (3) after the polyarylate resin is hydrolyzed, is 0.2% to 1%, in terms of intensity ratio, based on the total amount of bisphenol residues represented by formula (2) and formula (3) after the polyarylate resin is hydrolyzed, the bisphenol residues being detected with a gas chromatograph employing a hydrogen flame ionization detector (FID).

Abstract: The present invention relates to an electrophotographic photoreceptor comprising a conductive support and a photosensitive layer disposed thereover, wherein the photosensitive layer comprises a compound represented by general formula (1) and palladium, the photosensitive layer having a palladium content of 0.01-50 ppm.

Abstract: The present invention relates to an electrophotographic photoreceptor comprising a conductive support and a photosensitive layer disposed thereover, wherein the photosensitive layer comprises a compound represented by general formula (1) and palladium, the photosensitive layer having a palladium content of 0.01-50 ppm.

Abstract: The present invention relates to an electrophotographic photoreceptor comprising a conductive support and at least a photosensitive layer provided thereon, wherein the electrophotographic photoreceptor comprises an outermost layer which contains a specific charge transport substance and a specific compound.

Abstract: An electrophotographic photoreceptor comprises a conductive support and, at least a photosensitive layer on the conductive support, wherein the photosensitive layer includes a polyarylate resin and the polyarylate resin has a repeating structure represented by formula (1), and the amount of bisphenol residues represented by formula (3) after the polyarylate resin is hydrolyzed, is 0.2% to 1%, in terms of intensity ratio, based on the total amount of bisphenol residues represented by formula (2) and formula (3) after the polyarylate resin is hydrolyzed, the bisphenol residues being detected with a gas chromatograph employing a hydrogen flame ionization detector (FID).

Abstract: An electrophotographic photoreceptor comprising at least a photosensitive layer on a conductive support, wherein the photosensitive layer contains a specific compound and a specific charge-transporting substance.

Abstract: The present invention is intended to provide an electrophotographic photoreceptor that does not easily cause defects such as filming, insufficient cleaning, and abnormal noise, and that has many other desirable properties, including excellent abrasion resistance, excellent adhesion to a substrate and a lower layer, excellent electrical properties including fast response and sufficiently low exposure electric potential, and excellent gas resistance and image memory characteristics. The present invention relates to an electrophotographic photoreceptor that has at least a photosensitive layer on an electrocondutive support. The photosensitive layer contains a charge transport substance of a specific structure, and a specific polyester resin.

Abstract: The present invention relates to an electrophotographic photoreceptor comprising a conductive support and at least a photosensitive layer provided thereon, wherein the electrophotographic photoreceptor comprises an outermost layer which contains a specific charge transport substance and a specific compound.

Abstract: To provide an electrophotographic photoreceptor having a high sensitivity, a good balance of various electric properties such as chargeability and residual potential, a good stability of the coating solution, and an excellent light resistance. An electrophotographic photoreceptor comprising an electroconductive support having thereon a photosensitive layer, wherein the photosensitive layer contains a compound represented by the following formula (1): (wherein R1 represents a group having a chiral center, R2 represents a hydrogen atom, an alkyl group which may have a substituent, or an aryl group which may have a substituent, R3 and R4 each independently represents an alkylene group which may have a substituent, or an arylene group which may have a substituent, and R5, R6, R7 and R8 each independently represents an alkyl group which may have a substituent, or an aryl group which may have a substituent, and at least one member of R5 to R8 is an aryl group having a substituent).

Abstract: An electrophotographic photoreceptor is provided which comprises a conductive substrate and a photosensitive layer formed thereover, wherein the photosensitive layer contains at least a polyarylate resin having a repeating structure represented by the following formula [1] and a compound represented by the following formula [6]. This photoreceptor has excellent abrasion resistance under practical load, has high mechanical strength, and further has highly excellent electrical properties.

Abstract: To provide an electrophotographic photoreceptor having a high sensitivity, a good balance of various electric properties such as chargeability and residual potential, a good stability of the coating solution, and an excellent light resistance. An electrophotographic photoreceptor comprising an electroconductive support having thereon a photosensitive layer, wherein the photosensitive layer contains a compound represented by the following formula (1): (wherein R1 represents a group having a chiral center, R2 represents a hydrogen atom, an alkyl group which may have a substituent, or an aryl group which may have a substituent, R3 and R4 each independently represents an alkylene group which may have a substituent, or an arylene group which may have a substituent, and R5, R6, R7 and R8 each independently represents an alkyl group which may have a substituent, or an aryl group which may have a substituent, and at least one member of R5 to R8 is an aryl group having a substituent).

Abstract: To realize an electrophotographic photoreceptor excellent in abrasion resistance, the photosensitive layer of the photoreceptor comprises a polyester resin containing a repeating structural unit represented by the formula (1) and a hydrazone compound. (In the formula (1), Ar1 to Ar4 each represents, independently of each other, an arylene group which may have a substituent. X1 represents a bivalent group (including a single bond) and X2 represents a bivalent group (including a single bond) with 3 or less atoms.

Abstract: To provide an electrophotographic photoreceptor having a high sensitivity, a good balance of various electric properties such as chargeability and residual potential, a good stability of the coating solution, and an excellent light resistance. An electrophotographic photoreceptor comprising an electroconductive support having thereon a photosensitive layer, wherein the photosensitive layer contains a compound represented by the following formula (1): (wherein R1 represents a group having a chiral center, R2 represents a hydrogen atom, an alkyl group which may have a substituent, or an aryl group which may have a substituent, R3 and R4 each independently represents an alkylene group which may have a substituent, or an arylene group which may have a substituent, and R5, R6, R7 and R8 each independently represents an alkyl group which may have a substituent, or an aryl group which may have a substituent, and at least one member of R5 to R8 is an aryl group having a substituent).

Abstract: An electrophotographic photoreceptor comprising a conductive support and a photosensitive layer formed thereon, wherein the photosensitive layer comprises a polyarylate resin having a repeating structure represented by the following formula [1] and a compound represented by the following formula [6]. This electrophotographic photoreceptor has excellent wearing resistance under load in the practical use of the photoreceptor and has high mechanical strength and extremely satisfactory electrical characteristcis.

Abstract: To realize an electrophotographic photoreceptor excellent in abrasion resistance, the photosensitive layer of the photoreceptor comprises a polyester resin containing a repeating structural unit represented by the formula (1) and a hydrazone compound. (In the formula (1), Ar1 to Ar4 each represents, independently of each other, an arylene group which may have a substituent. X1 represents a bivalent group (including a single bond) and X2 represents a bivalent group (including a single bond) with 3 or less atoms.