Abstract: A polyarylate resin includes repeating units represented by formulas (1), (2), (3), and (4). A percentage of the number of repeats of the repeating unit represented by formula (3) relative to the total number of repeats of the respective repeating units represented by formulas (1) and (3) is greater than 0% and less than 20%. In formula (1), R1 and R2 each represent, independently of one another, a hydrogen atom or a methyl group and X represents a divalent group represented by formula (X1) or (X2). In formula (2), W represents, a divalent group represented by formula (W1) or (W2).

Abstract: A polyarylate resin includes repeating units represented by formulas (1), (2), and (4). The polyarylate resin further includes a repeating unit represented by formula (3) and a percentage of the number of repeats of the repeating unit represented by formula (3) relative to the total number of repeats of the respective repeating units represented by formulas (1) and (3) is greater than 0% and less than 50%. Or, the polyarylate resin does not include the repeating unit represented by formula (3). In formula (1), R1 and R2 each represent, independently of one another, a hydrogen atom or a methyl group and X represents a divalent group represented by formula (X1) or (X2). In formula (3), R5 and R6 each represent, independently of one another, a hydrogen atom or a methyl group.

Abstract: A polyarylate resin includes repeating units represented by formulas (1), (2), (3), and (4). A third percentage is greater than 0% and less than 50%. The third percentage is a percentage of the number of repeats of the repeating unit represented by formula (3) relative to the total of the number of repeats of the repeating unit represented by formula (1) and the number of repeats of the repeating unit represented by formula (3). A fourth percentage is at least 35% and less than 70%. The fourth percentage is a percentage of the number of repeats of the repeating unit represented by formula (4) relative to the total of the number of repeats of the repeating unit represented by formula (2) and the number of repeats of the repeating unit represented by formula (4).

Abstract: A polyarylate resin includes repeating units (1), (2), and (4). The polyarylate resin further includes a repeating unit (3) and a percentage of the number of repeats of the repeating unit (3) relative to the total number of repeats of each of the repeating units (1) and (3) is greater than 0% and less than 50%. Alternatively, the polyarylate resin does not include the repeating unit (3).

Abstract: An electrophotographic photosensitive member includes a conductive substrate and a photosensitive layer. The photosensitive layer is a single layer and contains a charge generating material, an electron transport material, a binder resin, and a hole transport material. The electron transport material includes a compound represented by general formula (1): In general formula (1), R1 and R2 each represent, independently of one another, a hydrogen atom, an alkyl group, a heterocyclic group, an alkoxy group, an aralkyl group, an allyl group, or an aryl group optionally substituted with at least 1 and no more than 5 substituents selected from the group consisting of a halogen atom, an alkyl group, and alkoxy group.

Abstract: A compound is represented by general formula (1). In general formula (1), R1 and R2 each represent, independently of one another, a hydrogen atom, a methyl group, or an ethyl group, and a sum of the number of carbon atoms of the chemical group represented by R1 and the number of carbon atoms of the chemical group represented by R2 is 2. R3 and R4 each represent, independently of one another, a hydrogen atom, a methyl group, or an ethyl group, and a sum of the number of carbon atoms of the chemical group represented by R3 and the number of carbon atoms of the chemical group represented by R1 is 2. A photosensitive layer of an electrophotographic photosensitive member contains at least a charge generating material, a hole transport material, and a binder resin.

Abstract: A photosensitive layer included in an electrophotographic photosensitive member contains at least a charge generating material, a hole transport material, and a binder resin. The hole transport material includes a compound (1). The binder resin includes a polyarylate resin having at least one repeating unit (10) and at least one repeating unit (11). Alternatively, the binder resin includes a polycarbonate resin having a repeating unit (20) and a repeating unit (21).

Abstract: An electrophotographic photosensitive member (1) includes a conductive substrate (2) and a photosensitive layer (3) disposed directly or indirectly on the conductive substrate (2). The photosensitive layer (3) has a charge generating layer (3a) and a charge transport layer (3b) disposed in order from the conductive substrate (2). The charge generating layer (3a) contains a charge generating material. The charge transport layer (3b) contains a charge transport material, a binder resin, and a pigment that absorbs light having an irradiation wavelength.

Abstract: A bis-butadiene derivative is represented by general formula (1) shown below. In general formula (1), Ra, Rb, and Rc each represent, independently of one another, an alkyl group having a carbon number of at least 1 and no greater than 8 or an alkoxy group having a carbon number of at least 1 and no greater than 8. l and m each represent, independently of one another, an integer of at least 0 and no greater than 5. n represents an integer of at least 0 and no greater than 4. Chemical groups Ra may be the same as or different from each other. Chemical groups Rb may be the same as or different from each other. Chemical groups Rc may be the same as or different from each other.

Abstract: A method for producing an electrophotographic photosensitive member includes an electrically conductive substrate and a photosensitive layer. The method includes applying an application liquid for photosensitive layer formation containing a solvent, a binder resin, and a hole transport material directly or indirectly onto the electrically conductive substrate, and removing a portion of the solvent, to form the photosensitive layer. The solvent contains a first solvent that is an alcohol having a carbon number of at least 1 and no greater than 3, and a second solvent other than the first solvent.

Abstract: An electrophotographic photosensitive member includes a photosensitive layer. The photosensitive layer contains a charge generating material, a hole transport material, and a binder resin. The binder resin contains a polyarylate resin represented by general formula (1). In general formula (1), r and s each represent an integer of at least 0 and no greater than 49 and t and u represents an integer of at least 1 and no greater than 50. Furthermore, r+s+t+u=100 and r+t=s+u. X and Y each represent, independently of one another, a divalent group represented by chemical formula (1-1), (1-2), (1-3), or (1-4).

Abstract: A photosensitive member (1) includes a conductive substrate (2) and a photosensitive layer (3). The photosensitive layer is a single-layer photosensitive layer (3c). The photosensitive layer contains a charge generating material, a hole transport material, an electron transport material, and a binder resin. The hole transport material includes a triphenylamine derivative represented by general formula (HT). The electron transport material includes a compound represented by general formula (ET1), (ET2), (ET3), (ET4), or (ET5).

Abstract: A naphthalenedicarboxylic acid dichloride production method includes causing a reaction between naphthalenedicarboxylic acid and a chlorinating agent at a reaction temperature of 20° C. or higher and 75° C. or lower in presence of a solvent including tetrahydrofuran. The causing a reaction in the naphthalenedicarboxylic acid dichloride production method is preferably performed in presence of N,N-disubstituted formamide.

Abstract: An electrophotographic photosensitive member (1) includes a conductive substrate (2) and a photosensitive layer (3). The photosensitive layer (3) is a single-layer photosensitive layer (3c) and contains a charge generating material, a hole transport material, an electron transport material, and a binder resin. The binder resin includes a polyarylate resin represented by general formula (1). In general formula (1), Q1, Q2, Q3, and Q4 each represent a methyl group or a hydrogen atom. r, s, t, and u each represent a number greater than or equal to 15 and less than or equal to 35.

Abstract: An electrophotographic photosensitive member includes a conductive substrate, a charge generating layer, and a charge transport layer. The charge generating layer has a thickness of at least 0.07 ?m. The charge transport layer contains a binder resin, a hole transport material, and meta-terphenyl. The binder resin includes a polyarylate resin including repeating units and a group represented by respective general formulas (1) to (3). The electrophotographic photosensitive member satisfies at least two conditions of: (A) the charge generating layer has a thickness of at least 0.12 ?m; (B) the charge transport layer contains a specific amount of fluororesin particles; and (C) the charge transport layer contains meta-terphenyl in an amount of at least 5.0 parts by mass and no greater than 15.0 parts by mass relative to 100 parts by mass of the binder resin.

Abstract: A photosensitive layer included in an electrophotographic photosensitive member contains at least a charge generating material, a hole transport material, and a binder resin. The hole transport material includes a compound (1). The binder resin includes a polyarylate resin having at least one repeating unit (10) and at least one repeating unit (11). Alternatively, the binder resin includes a polycarbonate resin having a repeating unit (20) and a repeating unit (21).

Abstract: A compound is represented by general formula (1). In general formula (1), R1 and R2 each represent, independently of one another, a hydrogen atom, a methyl group, or an ethyl group, and a sum of the number of carbon atoms of the chemical group represented by R1 and the number of carbon atoms of the chemical group represented by R2 is 2. R3 and R4 each represent, independently of one another, a hydrogen atom, a methyl group, or an ethyl group, and a sum of the number of carbon atoms of the chemical group represented by R3 and the number of carbon atoms of the chemical group represented by R1 is 2. A photosensitive layer of an electrophotographic photosensitive member contains at least a charge generating material, a hole transport material, and a binder resin.

Abstract: An electrophotographic photosensitive member (1) includes a conductive substrate (2) and a photosensitive layer (3). The photosensitive layer (3) is a single-layer photosensitive layer (3c) and contains a charge generating material, a hole transport material, an electron transport material, and a binder resin. The binder resin includes a polyarylate resin represented by general formula (1). In general formula (1), Q1, Q2, Q3, and Q4 each represent a methyl group or a hydrogen atom. r, s, t, and u each represent a number greater than or equal to 15 and less than or equal to 35.

Abstract: A naphthalenedicarboxylic acid dichloride production method includes causing a reaction between naphthalenedicarboxylic acid and a chlorinating agent at a reaction temperature of 20° C. or higher and 75° C. or lower in presence of a solvent including tetrahydrofuran. The causing a reaction in the naphthalenedicarboxylic acid dichloride production method is preferably performed in presence of N,N-disubstituted formamide.

Abstract: A compound mixture contains a mixture of a compound represented by general formula (1) and a compound represented by general formula (2). In the general formula (1), R1A, R2A, R3A, R4A, R5A, R6A, R7A, R8A, R9A, and R10A each represent, independently of one another, a hydrogen atom, an alkyl group having a carbon number of at least 1 and no greater than 8, an alkoxy group having a carbon number of at least 1 and no greater than 8, or an aryl group having a carbon number of at least 6 and no greater than 14.