Abstract: Provided is a liquid crosslinking agent in which liquid life (pot life) as an undiluted solution is sufficiently long and excellent coating properties are exhibited when used. A liquid crosslinking agent containing an epoxy compound and an emulsifier, in which a content of water is 39% by mass or less with respect to a total amount of a liquid, and a contact angle with respect to a poly(ethylene-methacrylic acid) film when preparing an aqueous dispersion in which a concentration of a non-volatile component is 15% by mass is 42.0° or less. It is preferable that the epoxy compound has two or more epoxy groups in molecules, and it is preferable that the emulsifier is a nonionic surfactant. Provided is a coating method of a liquid crosslinking agent including diluting the liquid crosslinking agent with water to be used for coating.

Abstract: The present invention relates to a liquid developer containing a carrier liquid and a developer component, in which the developer component contains an ethylene-(meth)acrylic acid copolymer A and a block copolymer B? containing a hard segment and a soft segment, and the hard segment is a vinyl alicyclic hydrocarbon polymer, an image forming method using the liquid developer, a liquid developer cartridge having the liquid developer and an image forming apparatus having the liquid developer.

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 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: Disclosed is an electrophotographic photoreceptor which is excellent in wear resistance and electrical characteristics. Specifically disclosed is an electrophotographic photoreceptor containing a polyester resin in a photosensitive layer provided on an electroconductive substrate. The polyester resin is composed of a copolymer represented by the general formula 1 below, which has a viscosity average molecular weight (Mv) of 10,000-300,000 and contains a diphenyl ether 4,4?-dicarboxylic acid component and a bivalent phenol component. In the general formula 1, A represents a diphenyl ether 4,4?-dicarboxylic acid residue represented by the formula A below, and B represents a bivalent phenol residue represented by the formula B below. In the formula A, each of Ra1 and Ra2 independently represents a hydrogen atom or a monovalent substituent which may have a substituent, and each of n and m is independently an integer from 0 to 4.

Abstract: Disclosed is an electrophotographic photoreceptor which is excellent in wear resistance and electrical characteristics. Specifically disclosed is an electrophotographic photoreceptor containing a polyester resin in a photosensitive layer provided on an electroconductive substrate. The polyester resin is composed of a copolymer of formula (4), which has a viscosity average molecular weight (Mv) of 10,000-300,000 and contains a diphenyl ether 4,4?-dicarboxylic acid component and a bivalent phenol component. A represents a diphenyl ether 4,4?-dicarboxylic acid residue of formula (A), and E represents a bivalent phenol residue of formula (E). In formula (A), each of Ra1 and Ra2 independently represents a hydrogen atom or a monovalent substituent which may have a substituent, and each of n and m is independently an integer from 0 to 4.

Abstract: The present invention relates to an electrophotographic photoreceptor comprising an electroconductive substrate and a photosensitive layer formed thereon, wherein the photosensitive layer contains a polyester resin consisting of a repeating ester structure consisting of at least one bivalent phenol residue having formula (1) and at least one of an aromatic dicarboxylic acid residue having formula (2): where, each of R1 to R4, which are independent of one another, represents hydrogen or a methyl group, and R5 represents a methyl group, where (i) R1 to R4 are hydrogen atoms; or (iii) R1 and R3 are methyl groups and R2 and R4 are hydrogen atoms, and where the polyester resin is a copolymer, and an amount of the repeating ester structure consisting of the bivalent phenol residue having the above formula (1) and the aromatic dicarboxylic acid residue having the above formula (2) is at least 10 wt % of the entire polyester resin of the copolymer.

Abstract: Disclosed is an electrophotographic photoreceptor which is excellent in wear resistance and electrical characteristics. Specifically disclosed is an electrophotographic photoreceptor containing a polyester resin in a photosensitive layer provided on an electroconductive substrate. The polyester resin is composed of a copolymer represented by the general formula 1 below, which has a viscosity average molecular weight (Mv) of 10,000-300,000 and contains a diphenyl ether 4,4?-dicarboxylic acid component and a bivalent phenol component. [Chemical Formula 1] A-Bn??(1) In the general formula 1, A represents a diphenyl ether 4,4?-dicarboxylic acid residue represented by the formula A below, and B represents a bivalent phenol residue represented by the formula B below. In the formula A, each of Ra1 and Ra2 independently represents a hydrogen atom or a monovalent substituent which may have a substituent, and each of n and m is independently an integer from 0 to 4.

Abstract: It is to provide a high performance and ultralife electrophotographic photoreceptor, which is less likely to be chemically and electrically deteriorated even when repeatedly used, which can maintain excellent electric characteristics, the photosensitive layer surface of which is less likely to be abraded or scarred or undergo film peeling due to e.g. contact with a developing apparatus, a developer or paper, and which is excellent also in mechanical characteristics. An electrophotographic photoreceptor, which contains a polyester resin having a repeating structure comprising a bivalent phenol residue represented by the following formula (1) and an aromatic dicarboxylic acid residue represented by the following formula (2): in the formula (1), each of R1 to R4 which are independent of one another, represents a hydrogen atom or an alkyl group, and R5 represents an alkyl group.

Abstract: Disclosed is an electrophotographic photoreceptor which is excellent in wear resistance and electrical characteristics. Specifically disclosed is an electrophotographic photoreceptor containing a polyester resin in a photosensitive layer provided on an electroconductive substrate. The polyester resin is composed of a copolymer represented by the general formula 1 below, which has a viscosity average molecular weight (Mv) of 10,000-300,000 and contains a diphenyl ether 4,4?-dicarboxylic acid component and a bivalent phenol component. In the general formula 1, A represents a diphenyl ether 4,4?-dicarboxylic acid residue represented by the formula A below, and B represents a bivalent phenol residue represented by the formula B below. In the formula A, each of Ra1 and Ra2 independently represents a hydrogen atom or a monovalent substituent which may have a substituent, and each of n and m is independently an integer from 0 to 4.

Abstract: An electrophotographic photoreceptor, which contains a polyester resin having a repeating structure comprising a bivalent phenol residue represented by the following formula (1) and an aromatic dicarboxylic acid residue represented by the following formula (2): in the formula (1), each of R1 to R4 which are independent of one another, represents a hydrogen atom or an alkyl group, and R5 represents an alkyl group.

Abstract: Disclosed is an electrophotographic photoreceptor which is excellent in wear resistance and electrical characteristics. Specifically disclosed is an electrophotographic photoreceptor containing a polyester resin in a photosensitive layer provided on an electroconductive substrate. The polyester resin is composed of a copolymer represented by the general formula 1 below, which has a viscosity average molecular weight (Mv) of 10,000-300,000 and contains a diphenyl ether 4,4?-dicarboxylic acid component and a bivalent phenol component. [Chemical Formula 1] ?A-B?n??(1) In the general formula 1, A represents a diphenyl ether 4,4?-dicarboxylic acid residue represented by the formula A below, and B represents a bivalent phenol residue represented by the formula B below. In the formula A, each of Ra1 and Ra2 independently represents a hydrogen atom or a monovalent substituent which may have a substituent, and each of n and m is independently an integer from 0 to 4.

Abstract: An electrophotographic photoreceptor including an electroconductive substrate and a photosensitive layer formed thereon, the photosensitive layer containing a polyester resin which is a copolymerized polyester resin having at least two different types of repeating ester structure (A) each comprising a bivalent phenol residue represented by invention formula (1) and an aromatic dicarboxylic acid residue represented by invention formula (3), and a repeating ester structure (B) comprising a bivalent phenol residue represented by invention formula (2) and an aromatic dicarboxylic acid residue represented by invention formula (3):

Abstract: It is to provide a high performance and ultralife electrophotographic photoreceptor, which is less likely to be chemically and electrically deteriorated even when repeatedly used, which can maintain excellent electric characteristics, the photosensitive layer surface of which is less likely to be abraded or scarred or undergo film peeling due to e.g. contact with a developing apparatus, a developer or paper, and which is excellent also in mechanical characteristics.

Abstract: It is to provide a high performance and ultralife electrophotographic photoreceptor, which is less likely to be chemically and electrically deteriorated even when repeatedly used, which can maintain excellent electric characteristics, the photosensitive layer surface of which is less likely to be abraded or scarred or undergo film peeling due to e.g. contact with a developing apparatus, a developer or paper, and which is excellent also in mechanical characteristics. An electrophotographic photoreceptor, which contains a polyester resin having a repeating structure comprising a bivalent phenol residue represented by the following formula (1) and an aromatic dicarboxylic acid residue represented by the following formula (2): in the formula (1), each of R1 to R4 which are independent of one another, represents a hydrogen atom or an alkyl group, and R5 represents an alkyl group.

Abstract: Electrophotographic photoreceptors having improved mechanical properties, electrical properties with excellent response characteristics are prepared by forming a photosensitive layer on an electroconductive substrate. The photosensitive layer contains a binder resin, which may be a polyarylate or a copolymer of polyarylate. The binder resin may be mixed with other resins up to 50 wt % with other resins to impove surface slip properties or fire retardant properties.

Abstract: A high-sensitivity and long-life electrophotographic photoreceptor comprising an electroconductive substrate and at least a photosensitive layer on the electroconductive substrate is provided, wherein the photosensitive layer contains a polyarylate resin not having a nitrogen atom in its repeating unit, and the Hall mobility at an electric field strength of 3×105 (V/cm) and at a temperature of 21° C. of the photosensitive layer is 3×10−6 (cm2/Vs) or more.

Abstract: A high-sensitivity and long-life electrophotographic photoreceptor comprising an electroconductive substrate and at least a photosensitive layer on the electroconductive substrate is provided, wherein the photosensitive layer contains a polyarylate resin not having a nitrogen atom in its repeating unit, and the Hall mobility at an electric field strength of 3×105 (V/cm) and at a temperature of 21° C. of the photosensitive layer is 3×10−6 (cm2/Vs) or more.

Abstract: Electrophotographic photoreceptors having improved mechanical properties, electrical properties with excellent response characteristics are prepared by forming a photosensitive layer on an electroconductive substrate. The photosensitive layer contains a binder resin, which may be a polyarylate or a copolymer of polyarylate. The binder resin may be mixed with other resins up to 50 wt % with other resins to impove surface slip properties or fire retardant properties.

Abstract: A high-sensitivity and long-life electrophotographic photoreceptor comprising an electroconductive substrate and at least a photosensitive layer on the electroconductive substrate is provided, wherein the photosensitive layer contains a polyarylate resin not having a nitrogen atom in its repeating unit, and the Hall mobility at an electric field strength of 3×105 (V/cm) and at a temperature of 21° C. of the photosensitive layer is 3×10−6 (cm2/Vs) or more.