WO2018163597A1

WO2018163597A1 - Electrophotographic photosensitive body

Info

Publication number: WO2018163597A1
Application number: PCT/JP2018/000668
Authority: WO
Inventors: 岡田　英樹
Original assignee: 京セラドキュメントソリューションズ株式会社
Priority date: 2017-03-08
Filing date: 2018-01-12
Publication date: 2018-09-13
Also published as: JPWO2018163597A1; CN110383181B; CN110383181A; JP6702500B2

Abstract

This electrophotographic photosensitive body (100) is provided with a conductive substrate (101) and a single photosensitive layer (102). The photosensitive layer (102) contains at least a charge generating agent and a compound represented by general formula (1). In general formula (1), R1 represents a C1-10 alkyl group, a C1-6 alkoxy group, a C7-20 aralkyl group, a C3-10 cycloalkyl group or a C6-14 aryl group which may have at least one substituent; each of R2, R3 and R4 independently represents a hydrogen atom, a halogen atom, a C1-10 alkyl group, a C1-6 alkoxy group, a C7-20 aralkyl group, a C3-10 cycloalkyl group or a C6-14 aryl group; and R3 and R4 may combine together to form a ring.

Description

Electrophotographic photoreceptor

The present invention relates to an electrophotographic photoreceptor.

The electrophotographic photoreceptor is used in an electrophotographic image forming apparatus. As the electrophotographic photosensitive member, for example, a multilayer electrophotographic photosensitive member or a single layer type electrophotographic photosensitive member is used. The multilayer electrophotographic photoreceptor includes, as a photosensitive layer, a charge generation layer having a charge generation function and a charge transport layer having a charge transport function. The single-layer electrophotographic photosensitive member includes a single-layer photosensitive layer having a charge generation function and a charge transport function as a photosensitive layer.

The electrophotographic photoreceptor described in Patent Document 1 includes a photosensitive layer. This photosensitive layer contains, for example, a naphthalene tetracarboxylic acid diimide derivative having a structure represented by the chemical formula (E-1) as an electron transport material.

JP 2005-154444 A

However, the electrophotographic photosensitive member described in Patent Document 1, specifically, an electrophotographic photosensitive member having a photosensitive layer containing a naphthalene tetracarboxylic acid diimide derivative having a structure represented by the chemical formula (E-1) has poor sensitivity characteristics. It has been found out by the inventors that this is sufficient.

The present invention has been made in view of the above-described problems, and an object thereof is to provide an electrophotographic photoreceptor excellent in sensitivity characteristics.

The electrophotographic photoreceptor of the present invention comprises a conductive substrate and a single photosensitive layer. The photosensitive layer contains at least a charge generating agent and a compound represented by the following general formula (1).

In the general formula (1), R ¹ is an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an aralkyl group having 7 to 20 carbon atoms, and 3 or more carbon atoms. 10 or less cycloalkyl group or an aryl group having 6 to 14 carbon atoms which may have at least one substituent. The substituent includes a halogen atom, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an aralkyl group having 7 to 20 carbon atoms, and a cyclohexane having 3 to 10 carbon atoms. An alkyl group or an aryl group having 6 to 14 carbon atoms. R ² , R ³ and R ⁴ are each independently a hydrogen atom, a halogen atom, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, or 7 to 20 carbon atoms. An aralkyl group, a cycloalkyl group having 3 to 10 carbon atoms, or an aryl group having 6 to 14 carbon atoms is represented. R ³ and R ⁴ may be bonded to each other to represent a ring.

The electrophotographic photoreceptor of the present invention is excellent in sensitivity characteristics.

1 is a cross-sectional view illustrating an example of an electrophotographic photoreceptor according to an embodiment of the present invention. 1 is a cross-sectional view illustrating an example of an electrophotographic photoreceptor according to an embodiment of the present invention. 1 is a cross-sectional view illustrating an example of an electrophotographic photoreceptor according to an embodiment of the present invention. ¹ is a ¹ H-NMR spectrum of a compound represented by the chemical formula (1-2), and this compound is contained in the electrophotographic photosensitive member according to the embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail. However, the present invention is not limited to the following embodiments. The present invention can be implemented with appropriate modifications within the scope of the object of the present invention. In addition, about the location where description overlaps, although description may be abbreviate | omitted suitably, the summary of invention is not limited.

Hereinafter, a compound and its derivatives may be generically named by adding “system” after the compound name. In addition, when “polymer” is added after the compound name to indicate the polymer name, it means that the repeating unit of the polymer is derived from the compound or a derivative thereof.

Hereinafter, a halogen atom, an alkyl group having 1 to 10 carbon atoms, an alkyl group having 1 to 6 carbon atoms, an alkyl group having 1 to 4 carbon atoms, an alkyl group having 1 to 3 carbon atoms, carbon An alkoxy group having 1 to 6 atoms, an alkoxy group having 1 to 3 carbon atoms, an aryl group having 6 to 14 carbon atoms, an aryl group having 6 to 10 carbon atoms, and 3 to 10 carbon atoms A cycloalkyl group having 5 to 7 carbon atoms, a cycloalkane having 5 to 7 carbon atoms, a 5- to 7-membered heterocyclic ring, and an aralkyl group having 7 to 20 carbon atoms, Unless otherwise specified, each has the following meaning:

The alkyl group having 1 to 10 carbon atoms, the alkyl group having 1 to 6 carbon atoms, the alkyl group having 1 to 4 carbon atoms, and the alkyl group having 1 to 3 carbon atoms are each linear. Or it is branched and unsubstituted. Examples of the alkyl group having 1 to 10 carbon atoms include a methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, n-pentyl group, 1 -Methylbutyl group, 2-methylbutyl group, 3-methylbutyl group, 1-ethylpropyl group, 2-ethylpropyl group, 1,1-dimethylpropyl group, 1,2-dimethylpropyl group, 2,2-dimethylpropyl group, 1,2-dimethylpropyl group, n-hexyl group, 1-methylpentyl group, 2-methylpentyl group, 3-methylpentyl group, 4-methylpentyl group, 1,1-dimethylbutyl group, 1,2-dimethyl Butyl, 1,3-dimethylbutyl, 2,2-dimethylbutyl, 2,3-dimethylbutyl, 3,3-dimethylbutyl, 1,1,2-tri Chirupuropiru group, 1,2,2-trimethyl propyl group, 1-ethylbutyl group, 2-ethylbutyl group, 3-ethylbutyl group, heptyl group, octyl group, nonyl group and decyl group. Examples of the alkyl group having 1 to 6 carbon atoms are groups having 1 to 6 carbon atoms among the groups described as examples of alkyl groups having 1 to 10 carbon atoms. Examples of the alkyl group having 1 to 4 carbon atoms are groups having 1 to 4 carbon atoms among the groups described as examples of alkyl groups having 1 to 10 carbon atoms. Examples of the alkyl group having 1 to 3 carbon atoms are groups having 1 to 3 carbon atoms among the groups described as examples of alkyl groups having 1 to 10 carbon atoms.

The alkoxy group having 1 to 6 carbon atoms and the alkoxy group having 1 to 3 carbon atoms are each linear or branched and unsubstituted. Examples of the alkoxy group having 1 to 6 carbon atoms include methoxy group, ethoxy group, n-propoxy group, isopropoxy group, n-butoxy group, sec-butoxy group, tert-butoxy group, n-pentoxy group, An isopentoxy group, a neopentoxy group and a hexyl group can be mentioned. Examples of the alkoxy group having 1 to 3 carbon atoms are groups having 1 to 3 carbon atoms among the groups described as examples of alkoxy groups having 1 to 6 carbon atoms.

The aryl group having 6 to 14 carbon atoms and the aryl group having 6 to 10 carbon atoms are each unsubstituted. Examples of the aryl group having 6 to 14 carbon atoms include a phenyl group, a naphthyl group, an indacenyl group, a biphenylenyl group, an acenaphthylenyl group, an anthryl group, and a phenanthryl group. Examples of the aryl group having 6 to 10 carbon atoms include a phenyl group and a naphthyl group.

The cycloalkyl group having 3 to 10 carbon atoms and the cycloalkyl group having 5 to 7 carbon atoms are each unsubstituted. Examples of the cycloalkyl group having 3 to 10 carbon atoms include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, a cyclononyl group, and a cyclodecyl group. Examples of the cycloalkyl group having 5 to 7 carbon atoms are groups having 5 to 7 carbon atoms among the groups described as examples of cycloalkyl groups having 3 to 10 carbon atoms.

A cycloalkane having 5 to 7 carbon atoms is unsubstituted. Examples of the cycloalkane having 5 to 7 carbon atoms include cyclopentane, cyclohexane and cycloheptane.

-5 to 7-membered heterocycle is unsubstituted. The 5- to 7-membered heterocycle contains at least one heteroatom other than the carbon atom. A hetero atom is a nitrogen atom, a sulfur atom or an oxygen atom. Examples of the 5- to 7-membered heterocycle include dioxolane, furan, thiophene, pyrrole, pyrrole, oxazole, isoxazole, thiazole, isothiazole, imidazole, pyrazole, furazane, pyran, pyridine, pyridazine, pyrimidine, pyrazine, Examples include pyrroline, pyrrolidine, imidazoline, imidazolidine, oxadiazine, dithiazine, oxathiane, azepine, triazine, thiolane, pyrazoline, pyrazolidine, piperidine, piperazine and morpholine.

An aralkyl group having 7 to 20 carbon atoms is unsubstituted. Examples of the aralkyl group having 7 to 20 carbon atoms include an alkyl group having 1 to 6 carbon atoms having an aryl group having 6 to 14 carbon atoms.

<Electrophotographic photoreceptor>
The present embodiment relates to an electrophotographic photoreceptor (hereinafter sometimes referred to as a photoreceptor). Hereinafter, the structure of the photoreceptor 100 will be described with reference to FIGS. 1A to 1C. 1A to 1C are cross-sectional views showing examples of the photoreceptor 100 according to this embodiment.

As shown in FIG. 1A, the photoreceptor 100 includes, for example, a conductive substrate 101 and a photosensitive layer 102. The photosensitive layer 102 is a single layer (single layer). The photoreceptor 100 is a single layer type electrophotographic photoreceptor including a single layer photosensitive layer 102.

As shown in FIG. 1B, the photoreceptor 100 may include a conductive substrate 101, a photosensitive layer 102, and an intermediate layer 103 (undercoat layer). The intermediate layer 103 is provided between the conductive substrate 101 and the photosensitive layer 102. As shown in FIG. 1A, the photosensitive layer 102 may be provided directly on the conductive substrate 101. Alternatively, as shown in FIG. 1B, the photosensitive layer 102 may be provided on the conductive substrate 101 with an intermediate layer 103 interposed therebetween. The intermediate layer 103 may be a single layer or a plurality of layers.

As shown in FIG. 1C, the photoreceptor 100 may include a conductive substrate 101, a photosensitive layer 102, and a protective layer 104. The protective layer 104 is provided on the photosensitive layer 102. The protective layer 104 may be a single layer or a plurality of layers.

The thickness of the photosensitive layer 102 is not particularly limited as long as the function as the photosensitive layer 102 can be sufficiently expressed. The thickness of the photosensitive layer 102 is preferably 5 μm or more and 100 μm or less, and more preferably 10 μm or more and 50 μm or less.

The structure of the photoconductor 100 has been described above with reference to FIGS. 1A to 1C. Hereinafter, the photoreceptor will be described in more detail.

<Photosensitive layer>
The photosensitive layer contains at least a charge generating agent and a compound represented by the general formula (1). The photosensitive layer may further contain a hole transport agent. The photosensitive layer may further contain a binder resin. The photosensitive layer may contain an additive as necessary.

(Compound (1))
The photosensitive layer contains a compound represented by the general formula (1) (hereinafter sometimes referred to as compound (1)). The photosensitive layer contains, for example, the compound (1) as an electron transport agent.

In the general formula (1), R ¹ is an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an aralkyl group having 7 to 20 carbon atoms, and 3 or more carbon atoms. 10 or less cycloalkyl group or an aryl group having 6 to 14 carbon atoms which may have at least one substituent. The substituent that the aryl group having 6 to 14 carbon atoms may have is a halogen atom, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, or 7 or more carbon atoms. An aralkyl group having 20 or less, a cycloalkyl group having 3 to 10 carbon atoms, or an aryl group having 6 to 14 carbon atoms. R ² , R ³ and R ⁴ are each independently a hydrogen atom, a halogen atom, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, or 7 to 20 carbon atoms. An aralkyl group, a cycloalkyl group having 3 to 10 carbon atoms, or an aryl group having 6 to 14 carbon atoms is represented. R ³ and R ⁴ may be bonded to each other to represent a ring.

When the photosensitive layer contains the compound (1), the sensitivity characteristics of the photoreceptor can be improved. The reason is presumed as follows. Compound (1) has two carbonyl groups which are electron-accepting groups. Moreover, the tricyclic condensed ring in the compound (1) has an asymmetric structure with respect to a line passing through two carbonyl groups. When the compound (1) has a tricyclic fused ring having an asymmetric structure, the solubility of the compound (1) in the solvent for forming the photosensitive layer is improved. Moreover, compatibility of the compound (1) with respect to binder resin improves because a compound (1) has a tricyclic condensed ring of an asymmetrical structure. By improving the solubility and compatibility, a uniform photosensitive layer can be formed, and the sensitivity characteristics of the photoreceptor are improved. It is also possible to suppress crystallization of the photosensitive layer of the photoreceptor.

The alkyl group having 1 to 10 carbon atoms represented by R ¹ to R ⁴ in the general formula (1) is preferably an alkyl group having 1 to 6 carbon atoms, and an alkyl group having 1 to 4 carbon atoms. Are more preferable, and a methyl group or a tert-butyl group is particularly preferable.

The alkoxy group having 1 to 6 carbon atoms represented by R ¹ to R ⁴ in the general formula (1) is preferably an alkoxy group having 1 to 3 carbon atoms, and more preferably a methoxy group.

The aralkyl group having 7 to 20 carbon atoms represented by R ¹ to R ⁴ in the general formula (1) is an alkyl group having 1 to 6 carbon atoms having a phenyl group, or the number of carbon atoms having a naphthyl group. 1 to 6 alkyl groups are preferred.

The cycloalkyl group having 3 to 10 carbon atoms represented by R ¹ to R ⁴ in the general formula (1) is preferably a cycloalkyl group having 5 to 7 carbon atoms, and more preferably a cyclohexyl group.

The aryl group having 6 to 14 carbon atoms represented by R ¹ to R ⁴ in the general formula (1) is preferably an aryl group having 6 to 10 carbon atoms, and more preferably a phenyl group.

The aryl group having 6 to 14 carbon atoms represented by R ¹ may have at least one substituent. When the aryl group having 6 to 14 carbon atoms has a substituent, the substituent that the aryl group having 6 to 14 carbon atoms has a halogen atom, an alkyl group having 1 to 10 carbon atoms, a carbon atom Examples thereof include an alkoxy group having 1 to 6 carbon atoms, an aralkyl group having 7 to 20 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, and an aryl group having 6 to 14 carbon atoms. The substituent of the aryl group having 6 to 14 carbon atoms is preferably an alkyl group having 1 to 10 carbon atoms, more preferably an alkyl group having 1 to 6 carbon atoms, and 1 to 3 carbon atoms. The following alkyl groups are more preferable, and a methyl group is particularly preferable. The number of substituents of the aryl group having 6 to 14 carbon atoms represented by R ¹ is preferably 1 or more, 5 or less, more preferably 1 or more and 3 or less, and even more preferably 2. .

The halogen atom represented by R ² to R ⁴ in the general formula (1) is preferably a chlorine atom or a fluorine atom, and more preferably a fluorine atom.

In the general formula (1), R ³ and R ⁴ may be bonded to each other to represent a ring together with the carbon atom to which R ³ is bonded and the carbon atom to which R ⁴ is bonded. The ring represented by R ³ and R ⁴ bonded to each other is preferably a cycloalkane having 5 to 7 carbon atoms or a heterocyclic ring having 5 to 7 members, more preferably a heterocyclic ring having 5 to 7 members. Further, a 5- to 7-membered heterocycle having an oxygen atom as a hetero atom is more preferable, and dioxolane is particularly preferable.

In the case where R ³ and R ⁴ in the general formula (1) are bonded to each other to represent a 5-membered to 7-membered heterocyclic ring, preferred examples of the compound (1) include those represented by the general formula (1-A). The compound which is made is mentioned.

R ¹ and R ² in formula (1-A), respectively, the same meaning as in formula (1) R ¹ and R ² in. In general formula (1-A), X ¹ , X ² and X ³ each independently represent —CH ₂ —, an oxygen atom, a sulfur atom or —NH—. However, at least one of X ¹ , X ² and X ³ represents an oxygen atom, a sulfur atom or —NH—. m represents an integer of 1 to 3. When m represents 2 or 3, a plurality of X ³ may be the same or different.

In general formula (1-A), X ¹ , X ² and X ³ each independently represent —CH ₂ — or an oxygen atom, provided that at least one of X ¹ , X ² and X ³ is oxygen Preferably it represents an atom. More preferably, X ¹ and X ³ represent an oxygen atom, and X ² represents —CH ₂ —. In general formula (1-A), m preferably represents 1 or 2, and more preferably represents 1.

In general formula (1), R ¹ has an alkyl group having 1 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, or at least one alkyl group having 1 to 10 carbon atoms. Represents an aryl group having 6 to 14 carbon atoms, and R ² , R ³ and R ⁴ each independently represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 10 carbon atoms, or the number of carbon atoms It preferably represents 1 to 6 alkoxy groups, and R ³ and R ⁴ may be bonded to each other to represent a 5- to 7-membered heterocyclic ring.

Preferable examples of compound (1) include compounds represented by chemical formulas (1-1), (1-2), (1-3), (1-4) and (1-5) (hereinafter, respectively) May be described as compounds (1-1), (1-2), (1-3), (1-4) and (1-5).

In order to further improve the sensitivity characteristics of the photoreceptor, in general formula (1), R ¹ is a cycloalkyl group having 3 to 10 carbon atoms, or at least one alkyl group having 1 to 10 carbon atoms. It is preferable to represent an aryl group having 6 to 14 carbon atoms that may have. In this case, the bond angle of R ¹ with respect to the tricyclic fused ring in the general formula (1) is increased. Due to the presence of R ^1, the tricyclic condensed ring of one compound (1) and the tricyclic condensed ring of the other compound (1) do not overlap too closely. Thereby, the space | interval of compound (1) can be kept moderate, and the solubility of compound (1) with respect to the solvent for photosensitive layer formation improves. As a result, a uniform photosensitive layer can be formed, and the sensitivity characteristic of the photoreceptor is improved. It is also possible to suppress crystallization of the photosensitive layer of the photoreceptor.

In order to further improve the sensitivity characteristics of the photoreceptor, in general formula (1), R ¹ is a cycloalkyl group having 3 to 10 carbon atoms, or at least one alkyl group having 1 to 10 carbon atoms. Represents an aryl group having 6 to 14 carbon atoms, and R ² , R ³ and R ⁴ each independently represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 10 carbon atoms or carbon More preferably, it represents an alkoxy group having 1 to 6 atoms, and R ³ and R ⁴ may be bonded to each other to represent a 5- to 7-membered heterocyclic ring. Preferable examples of such compound (1) include compounds (1-1), (1-2), (1-3) and (1-5).

In order to particularly improve the sensitivity characteristics of the photoreceptor, in general formula (1), R ² represents a hydrogen atom, and R ³ and R ⁴ are bonded to each other to represent a 5-membered to 7-membered heterocyclic ring. Is preferred. When R ³ and R ⁴ are bonded to each other to represent a 5-membered to 7-membered heterocyclic ring, a tetracyclic condensed ring is formed in the general formula (1). Thereby, the transport of electrons from the charge generator to the compound (1) and the transport of electrons between the compounds (1) can be more suitably performed. As a result, the sensitivity characteristics of the photoreceptor can be further improved.

In order to particularly improve the sensitivity characteristics of the photoreceptor, in the general formula (1), a 5- to 7-membered heterocyclic ring represented by R ³ and R ⁴ bonded to each other contains an oxygen atom as a hetero atom. It is preferable to have. Since the oxygen atom has an electron withdrawing property, the electron acceptability of the compound (1) is improved, and the sensitivity characteristics of the photoreceptor can be further improved.

In order to particularly improve the sensitivity characteristics of the photoreceptor, in general formula (1), R ¹ has a cycloalkyl group having 3 to 10 carbon atoms or at least one alkyl group having 1 to 10 carbon atoms. Represents an aryl group having 6 to 14 carbon atoms, R ² represents a hydrogen atom, and R ³ and R ⁴ are bonded to each other to form a 5- to 7-membered heterocycle (preferably a heteroatom And more preferably a 5-membered to 7-membered heterocycle having an oxygen atom. A preferred example of such compound (1) is compound (1-2).

In order to particularly improve the sensitivity characteristics of the photoreceptor, it is also preferable that R ² and R ³ each represent a hydrogen atom and R ⁴ represents a halogen atom in the general formula (1). Since the halogen atom has an electron withdrawing property, the electron acceptability of the compound (1) is improved, and the sensitivity characteristics of the photoreceptor can be further improved. In order to further improve the sensitivity characteristics of the photoreceptor, in general formula (1), R ¹ has a cycloalkyl group having 3 to 10 carbon atoms or at least one alkyl group having 1 to 10 carbon atoms. More preferably, it represents an aryl group having 6 to 14 carbon atoms, R ² and R ³ each represent a hydrogen atom, and R ⁴ represents a halogen atom. A preferred example of such compound (1) is compound (1-3).

The photosensitive layer may contain only the compound (1) as an electron transport agent. In addition to the compound (1), the photosensitive layer may further contain an electron transport agent other than the compound (1) (hereinafter sometimes referred to as other electron transport agent). Examples of other electron transport agents include quinone compounds, diimide compounds, hydrazone compounds, thiopyran compounds, trinitrothioxanthone compounds, 3,4,5,7-tetranitro-9-fluorenone compounds, dinitroanthracene compounds Examples thereof include compounds, dinitroacridine compounds, tetracyanoethylene, 2,4,8-trinitrothioxanthone, dinitrobenzene, dinitroacridine, succinic anhydride, maleic anhydride and dibromomaleic anhydride. Examples of quinone compounds include diphenoquinone compounds, azoquinone compounds, anthraquinone compounds, naphthoquinone compounds, nitroanthraquinone compounds, and dinitroanthraquinone compounds.

One type of compound (1) may be used alone, or two or more types may be used in combination. One of the other electron transfer agents may be used alone, or two or more may be used in combination. The content of the compound (1) is preferably 80% by mass or more, more preferably 90% by mass or more, and particularly preferably 100% by mass with respect to the total mass of the electron transport agent.

The content of the compound (1) is preferably 5 parts by mass or more and 100 parts by mass or less, and more preferably 20 parts by mass or more and 40 parts by mass or less with respect to 100 parts by mass of the binder resin. When the content of the compound (1) is 5 parts by mass or more with respect to 100 parts by mass of the binder resin, it is easy to improve the sensitivity characteristics of the photoreceptor. When the content of the compound (1) is 100 parts by mass or less with respect to 100 parts by mass of the binder resin, the compound (1) is easily dissolved in the solvent for forming the photosensitive layer, and a uniform photosensitive layer is easily formed. .

Next, the manufacturing method of a compound (1) is demonstrated. Compound (1) is produced, for example, according to a reaction represented by the following reaction formula (R-1) (hereinafter sometimes referred to as reaction (R-1)) or by a method analogous thereto. In addition to the reaction (R-1), the production method of the compound (1) may further include an appropriate step as necessary. Hereinafter, the compound represented by the chemical formula (A) represented by the reaction (R-1) is referred to as a compound (A). R ^1, R ^2, R ³ and R ⁴ in formula (A) are each the same meaning as in formula (1) R ^1, R ^2, R ³ and R ⁴ in.

In the reaction (R-1), 1 molar equivalent of the compound (A) is reacted to obtain 1 molar equivalent of the compound (1). In the reaction (R-1), first stirring and second stirring are performed. Specifically, the compound (A) is first stirred in the presence of a base and a solvent to obtain an intermediate product. Examples of the base include cesium carbonate, potassium carbonate, and sodium carbonate. Examples of the solvent include acetonitrile and alcohol having 1 to 3 carbon atoms. The first stirring may be performed in an atmosphere of an inert gas (for example, nitrogen gas). The reaction temperature in the first stirring is preferably 50 ° C. or higher and 120 ° C. or lower. The first stirring time is preferably 1 hour or more and 5 hours or less.

Next, the intermediate product obtained by the first stirring is secondly stirred in the presence of a palladium catalyst, a ligand of the palladium catalyst, a base and a solvent to obtain a compound (1). Examples of the palladium catalyst include known palladium catalysts, specifically, palladium (II) acetate, palladium (II) chloride, sodium hexachloropalladium (IV) tetrahydrate and tris (dibenzylideneacetone). ) Dipalladium (0). Examples of palladium catalyst ligands include triphenylphosphine, tributylphosphine, tricyclohexylphosphine, and methyldiphenylphosphine. Examples of bases include potassium carbonate and sodium carbonate. Examples of solvents include toluene and xylene. The second stirring may be performed in an atmosphere of an inert gas (for example, nitrogen gas). The reaction temperature in the second stirring is preferably 50 ° C. or higher and 120 ° C. or lower. The second stirring time is preferably 2 hours or more and 15 hours or less.

After the reaction (R-1), the obtained compound (1) may be purified. Examples of the purification method include known methods (for example, filtration, silica gel chromatography, or crystallization).

(Charge generator)
The charge generator is not particularly limited as long as it is a charge generator for a photoreceptor. Examples of the charge generator include phthalocyanine pigments, perylene pigments, bisazo pigments, trisazo pigments, dithioketopyrrolopyrrole pigments, metal-free naphthalocyanine pigments, metal naphthalocyanine pigments, squaraine pigments, indigo pigments, azurenium pigments, cyanine Pigments, powders of inorganic photoconductive materials (eg selenium, selenium-tellurium, selenium-arsenic, cadmium sulfide or amorphous silicon), pyrylium pigments, ansanthrone pigments, triphenylmethane pigments, selenium pigments, toluidine pigments, Examples thereof include pyrazoline pigments and quinacridone pigments. A charge generating agent may be used individually by 1 type, and may be used in combination of 2 or more type.

Examples of the phthalocyanine pigment include metal-free phthalocyanine and metal phthalocyanine. Metal-free phthalocyanine is represented, for example, by the chemical formula (CGM2). Examples of the metal phthalocyanine include titanyl phthalocyanine, hydroxygallium phthalocyanine, and chlorogallium phthalocyanine. Titanyl phthalocyanine is represented by the chemical formula (CGM1). The phthalocyanine pigment may be crystalline or non-crystalline. The crystal shape of the phthalocyanine pigment (for example, α type, β type, Y type, V type or II type) is not particularly limited, and phthalocyanine pigments having various crystal shapes are used.

Examples of the crystal of metal-free phthalocyanine include a metal-free phthalocyanine X-type crystal (hereinafter sometimes referred to as X-type metal-free phthalocyanine). Examples of the crystal of titanyl phthalocyanine include α-type, β-type, and Y-type crystals of titanyl phthalocyanine (hereinafter sometimes referred to as α-type, β-type, and Y-type titanyl phthalocyanine).

For example, for a digital optical image forming apparatus (for example, a laser beam printer or a facsimile using a light source such as a semiconductor laser), it is preferable to use a photoreceptor having sensitivity in a wavelength region of 700 nm or more. Since it has a high quantum yield in a wavelength region of 700 nm or more, the charge generator is preferably a phthalocyanine pigment, more preferably a metal-free phthalocyanine or titanyl phthalocyanine, and even more preferably an X-type metal-free phthalocyanine or a Y-type titanyl phthalocyanine. Y-type titanyl phthalocyanine is particularly preferred.

Y-type titanyl phthalocyanine has a main peak at 27.2 ° of the Bragg angle (2θ ± 0.2 °) in the CuKα characteristic X-ray diffraction spectrum, for example. The main peak in the CuKα characteristic X-ray diffraction spectrum is a peak having the first or second highest intensity in a range where the Bragg angle (2θ ± 0.2 °) is 3 ° or more and 40 ° or less.

An example of a CuKα characteristic X-ray diffraction spectrum measurement method will be described. A sample (titanyl phthalocyanine) is filled in a sample holder of an X-ray diffractometer (for example, “RINT (registered trademark) 1100” manufactured by Rigaku Corporation), an X-ray tube Cu, a tube voltage 40 kV, a tube current 30 mA, and CuKα. An X-ray diffraction spectrum is measured under the condition of a characteristic X-ray wavelength of 1.542 mm. The measurement range (2θ) is, for example, 3 ° to 40 ° (start angle 3 °, stop angle 40 °), and the scanning speed is, for example, 10 ° / min.

An santhrone pigment is preferably used as a charge generating agent in a photoreceptor applied to an image forming apparatus using a short wavelength laser light source (for example, a laser light source having a wavelength of 350 nm to 550 nm).

The content of the charge generating agent is preferably 0.1 parts by weight or more and 50 parts by weight or less, and 0.5 parts by weight or more and 30 parts by weight or less with respect to 100 parts by weight of the binder resin contained in the photosensitive layer. More preferably, it is more preferably 0.5 parts by mass or more and 4.5 parts by mass or less.

(Hole transport agent)
Examples of the hole transporting agent include triphenylamine derivatives, diamine derivatives (for example, N, N, N ′, N′-tetraphenylbenzidine derivatives, N, N, N ′, N′-tetraphenylphenylenediamine derivatives, N, N, N ′, N′-tetraphenylnaphthylenediamine derivative, N, N, N ′, N′-tetraphenylphenanthrylenediamine derivative or di (aminophenylethenyl) benzene derivative), oxadiazole series Compounds (eg, 2,5-di (4-methylaminophenyl) -1,3,4-oxadiazole), styryl compounds (eg, 9- (4-diethylaminostyryl) anthracene), carbazole compounds (eg, , Polyvinylcarbazole), organic polysilane compounds, pyrazoline compounds (for example, 1-phenyl-3- (p- Methylamino phenyl) pyrazoline), hydrazone compounds, indole compounds, oxazole compounds, isoxazole compounds, thiazole compounds, thiadiazole compounds, imidazole compounds, pyrazole compounds and triazole compounds. A hole transport agent may be used individually by 1 type, and may be used in combination of 2 or more type.

The photosensitive layer preferably contains a compound represented by the general formula (10) (hereinafter sometimes referred to as the compound (10)). The photosensitive layer preferably contains the compound (10) as a hole transport agent, for example.

In the general formula (10), R ¹⁰¹ , R ¹⁰² , R ¹⁰³ , R ¹⁰⁴ , R ¹⁰⁵ and R ¹⁰⁶ are each independently an alkyl group having 1 to 6 carbon atoms or an alkoxy group having 1 to 6 carbon atoms. Represents a group or an aryl group having 6 to 14 carbon atoms. a, b, c and d each independently represent an integer of 0 or more and 5 or less. e and f each independently represents an integer of 0 or more and 4 or less.

When a represents an integer of 2 or more and 5 or less, the plurality of R ¹⁰¹ may be the same as or different from each other. When b represents an integer of 2 or more and 5 or less, the plurality of R ¹⁰² may be the same as or different from each other. When c represents an integer of 2 or more and 5 or less, the plurality of R ¹⁰³ may be the same as or different from each other. When d represents an integer of 2 or more and 5 or less, the plurality of R ¹⁰⁴ may be the same as or different from each other. When e represents an integer of 2 or more and 4 or less, the plurality of R ¹⁰⁵ may be the same as or different from each other. When f represents an integer of 2 or more and 4 or less, the plurality of R ¹⁰⁶ may be the same as or different from each other.

In general formula (10), R ¹⁰¹ , R ¹⁰² , R ¹⁰³ , R ¹⁰⁴ , R ^105, and R ¹⁰⁶ each independently preferably represents an alkyl group having 1 to 6 carbon atoms. More preferably, it represents an alkyl group of 3 or less, and more preferably a methyl group. a, b, c and d each independently preferably represent 0 or 1, and more preferably represent 1. e and f each independently preferably represent 0 or 1, and more preferably represent 1.

A preferred example of compound (10) is a compound represented by the following chemical formula (10-1) (hereinafter sometimes referred to as compound (10-1)).

The photosensitive layer may contain only the compound (10) as a hole transport agent. The content of the compound (10) is preferably 80% by mass or more, more preferably 90% by mass or more, and particularly preferably 100% by mass with respect to the mass of the hole transport agent.

The content of the hole transport agent contained in the photosensitive layer is preferably 10 parts by mass or more and 200 parts by mass or less, and preferably 10 parts by mass or more and 100 parts by mass or less with respect to 100 parts by mass of the binder resin. More preferred.

(Binder resin)
Examples of the binder resin include a thermoplastic resin, a thermosetting resin, and a photocurable resin. Examples of the thermoplastic resin include polycarbonate resin, polyarylate resin, styrene-butadiene copolymer, styrene-acrylonitrile copolymer, styrene-maleic acid copolymer, acrylic acid polymer, styrene-acrylic acid copolymer, Polyethylene resin, ethylene-vinyl acetate copolymer, chlorinated polyethylene resin, polyvinyl chloride resin, polypropylene resin, ionomer resin, vinyl chloride-vinyl acetate copolymer, alkyd resin, polyamide resin, urethane resin, polysulfone resin, diallyl phthalate Examples include resins, ketone resins, polyvinyl butyral resins, polyester resins, and polyether resins. As a thermosetting resin, a silicone resin, an epoxy resin, a phenol resin, a urea resin, and a melamine resin are mentioned, for example. As photocurable resin, the acrylic acid adduct of an epoxy compound and the acrylic acid adduct of a urethane compound are mentioned, for example. These binder resins may be used individually by 1 type, and may be used in combination of 2 or more type.

Among these resins, a polycarbonate resin is preferable because a photosensitive layer having an excellent balance of workability, mechanical properties, optical properties, and abrasion resistance can be obtained. Examples of the polycarbonate resin include bisphenol ZC type polycarbonate resin, bisphenol C type polycarbonate resin, bisphenol A type polycarbonate resin and bisphenol Z type polycarbonate resin. The bisphenol Z-type polycarbonate resin is a polycarbonate resin having a repeating unit represented by the following chemical formula (20). Hereinafter, the polycarbonate resin having a repeating unit represented by the chemical formula (20) may be referred to as a polycarbonate resin (20).

(Additive)
Examples of additives include deterioration inhibitors (for example, antioxidants, radical scavengers, singlet quenchers or ultraviolet absorbers), softeners, surface modifiers, extenders, thickeners, dispersion stabilizers. , Waxes, acceptors, donors, surfactants, plasticizers, sensitizers and leveling agents. Antioxidants include, for example, hindered phenols (eg, di (tert-butyl) p-cresol), hindered amines, paraphenylenediamine, arylalkanes, hydroquinones, spirochromans, spirodanone or derivatives thereof, organic sulfur compounds, and An organic phosphorus compound is mentioned.

<Conductive substrate>
The conductive substrate is not particularly limited as long as it can be used as the conductive substrate of the photoreceptor. The conductive substrate may be formed of a material having at least a surface portion having conductivity. An example of the conductive substrate is a conductive substrate formed of a conductive material. Another example of the conductive substrate is a conductive substrate coated with a conductive material. Examples of the conductive material include aluminum, iron, copper, tin, platinum, silver, vanadium, molybdenum, chromium, cadmium, titanium, nickel, palladium, indium, stainless steel, and brass. These conductive materials may be used alone or in combination of two or more (for example, as an alloy). Among these materials having conductivity, aluminum or an aluminum alloy is preferable because charge transfer from the photosensitive layer to the conductive substrate is good.

The shape of the conductive substrate is appropriately selected according to the structure of the image forming apparatus. Examples of the shape of the conductive substrate include a sheet shape and a drum shape. The thickness of the conductive substrate is appropriately selected according to the shape of the conductive substrate.

<Intermediate layer>
The intermediate layer (undercoat layer) contains, for example, inorganic particles and a resin (intermediate layer resin) used for the intermediate layer. The presence of the intermediate layer is considered to suppress the increase in resistance by smoothing the flow of current generated when the photosensitive member is exposed while maintaining an insulating state capable of suppressing the occurrence of leakage.

Examples of the inorganic particles include metal (for example, aluminum, iron or copper), metal oxide (for example, titanium oxide, alumina, zirconium oxide, tin oxide or zinc oxide) particles and non-metal oxide (for example, silica). Particles. These inorganic particles may be used individually by 1 type, and may use 2 or more types together.

The intermediate layer resin is not particularly limited as long as it can be used as a resin for forming the intermediate layer. The intermediate layer may contain an additive. Examples of the additive contained in the intermediate layer are the same as those of the additive contained in the photosensitive layer.

<Method for producing photoconductor>
The photoreceptor is manufactured, for example, as follows. The photoreceptor is manufactured by applying a coating solution for the photosensitive layer onto a conductive substrate and drying. The coating solution for the photosensitive layer is produced by dissolving or dispersing a charge generating agent, an electron transporting agent and components added as necessary (for example, a hole transporting agent, a binder resin and an additive) in a solvent. .

The solvent contained in the coating solution for the photosensitive layer is not particularly limited as long as each component contained in the coating solution can be dissolved or dispersed. Examples of solvents include alcohols (eg methanol, ethanol, isopropanol or butanol), aliphatic hydrocarbons (eg n-hexane, octane or cyclohexane), aromatic hydrocarbons (eg benzene, toluene or xylene), Halogenated hydrocarbons (eg dichloromethane, dichloroethane, carbon tetrachloride or chlorobenzene), ethers (eg dimethyl ether, diethyl ether, tetrahydrofuran, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether or propylene glycol monomethyl ether), ketones (eg acetone, Methyl ethyl ketone or cyclohexanone), esters (eg ethyl acetate or methyl acetate), dimethylformaldehyde, dimethylform And dimethyl sulfoxide. One of these solvents may be used alone, or two or more may be used in combination. In order to improve the workability during the production of the photoreceptor, it is preferable to use a non-halogen solvent (a solvent other than the halogenated hydrocarbon) as the solvent.

The coating solution is prepared by mixing each component and dispersing in a solvent. For mixing or dispersing, for example, a bead mill, a roll mill, a ball mill, an attritor, a paint shaker, or an ultrasonic disperser can be used.

The photosensitive layer coating solution may contain, for example, a surfactant in order to improve the dispersibility of each component.

The method for applying the photosensitive layer coating solution is not particularly limited as long as the coating solution can be uniformly applied onto the conductive substrate. Examples of the coating method include a blade coating method, a dip coating method, a spray coating method, a spin coating method, and a bar coating method.

The method for drying the photosensitive layer coating solution is not particularly limited as long as the solvent in the coating solution can be evaporated. For example, the method of heat-processing (hot-air drying) is mentioned using a high-temperature dryer or a vacuum dryer. The heat treatment conditions are, for example, a temperature of 40 ° C. or higher and 150 ° C. or lower and a time of 3 minutes or longer and 120 minutes or shorter.

It should be noted that the method for producing a photoreceptor may further include one or both of a step of forming an intermediate layer and a step of forming a protective layer as necessary. A known method is appropriately selected in the step of forming the intermediate layer and the step of forming the protective layer.

Hereinafter, the present invention will be described more specifically using examples. However, the present invention is not limited to the scope of the examples.

<Material for forming photosensitive layer>
The following charge generator, hole transport agent, binder resin and electron transport agent were prepared as materials for forming the photosensitive layer of the photoreceptor.

(Charge generator)
Y-type titanyl phthalocyanine and X-type metal-free phthalocyanine were prepared as charge generating agents. Y-type titanyl phthalocyanine was a titanyl phthalocyanine represented by the chemical formula (CGM1) described in the embodiment and having a Y-type crystal structure. The X-type metal-free phthalocyanine was a metal-free phthalocyanine represented by the chemical formula (CGM2) described in the embodiment and having an X-type crystal structure.

(Hole transport agent)
The compound (10-1) described in the embodiment was prepared as a hole transport agent.

(Binder resin)
A bisphenol Z-type polycarbonate resin was prepared as a binder resin. The bisphenol Z-type polycarbonate resin was a polycarbonate resin having a repeating unit represented by the chemical formula (20) described in the embodiment. The viscosity average molecular weight of the bisphenol Z-type polycarbonate resin was 50000.

(Electron transfer agent)
As the electron transfer agent, the compounds (1-1) to (1-5) described in the embodiment were prepared. Each of the compounds (1-1) to (1-5) was synthesized by the following method.

(Synthesis of Compound (1-1))
Compound (1-1) was synthesized according to the reaction represented by reaction formula (r-1) (hereinafter referred to as reaction (r-1)). The compounds represented by chemical formulas (A-1) to (A-5) described below are referred to as compounds (A-1) to (A-5), respectively. Moreover, the yield of each compound was calculated | required by molar ratio conversion.

In the reaction (r-1), the compound (A-1) was reacted to obtain the compound (1-1). Specifically, compound (A-1) (0.571 g, 1 mmol) was dissolved in acetonitrile (10 mL) to obtain a solution. Cesium carbonate (0.975 g, 3 mmol) was added to the solution to obtain a mixture. While the mixture was refluxed, the mixture was stirred at 100 ° C. for 3 hours under a nitrogen gas atmosphere. Subsequently, acetonitrile was distilled off from the mixed solution to obtain a residue. The residue was extracted with ethyl acetate and water to obtain an organic layer (ethyl acetate layer). Ethyl acetate was distilled off from the organic layer to obtain a first crude product.

To the first crude product, palladium acetate (34 mg, 0.15 mmol), triphenylphosphine (79 mg, 0.3 mmol), potassium carbonate (276 mg, 2 mmol), and toluene (30 mL) were added to obtain a mixture. . While the mixture was refluxed, the mixture was stirred at 100 ° C. for 10 hours under a nitrogen gas atmosphere. Subsequently, toluene was distilled off from the mixed solution to obtain a residue. The residue was extracted with ethyl acetate and water to obtain an organic layer (ethyl acetate layer). Ethyl acetate was distilled off from the organic layer to obtain a second crude product containing the compound (1-1). The second crude product was purified by silica gel column chromatography using ethyl acetate as a developing solvent. Thereby, the compound (1-1) was obtained. The yield of compound (1-1) was 0.17 g. The yield of compound (1-1) from compound (A-1) was 50%.

(Synthesis of compounds (1-2) to (1-5))
Each of the compounds (1-2) to (1-5) was synthesized by the same method as the synthesis of the compound (1-1) except that the following points were changed. In the synthesis of compound (1-1), 0.571 g (1 mmol) of compound (A-1) was added, but in the synthesis of each of compounds (1-2) to (1-5) A) The amount (mass and amount of substance) and the kind of compound shown in the column were added. As a result, instead of the compound (1-1), a reaction product of the type shown in Table 1 (any one of the compounds (1-2) to (1-5)) was obtained. Table 1 shows the yield of each of the compounds (1-1) to (1-5). Table 1 shows the yield of each of the compounds (1-1) to (1-5) from the compound shown in the compound (A) column. In the chemical formulas (A-2) to (A-5), “—OBz” represents a benzyloxy group.

Next, with reference to ¹ H-NMR (proton nuclear magnetic resonance spectroscopy), it was analyzed by ¹ H-NMR spectrum of the compound (1-1) to (1-5). The magnetic field strength was set to 300 MHz. Deuterated chloroform (CDCl ₃ ) was used as the solvent. Tetramethylsilane (TMS) was used as an internal standard substance. As a representative example of the compounds (1-1) to (1-5), the ¹ H-NMR spectrum of the compound (1-2) is shown in FIG. Further, the chemical shift value of the ¹ H-NMR spectrum of the compound (1-2) is shown below. From the measured ¹ H-NMR spectrum and chemical shift value, it was confirmed that the compound (1-2) was obtained. For compounds (1-1) and (1-3) to (1-5), from the measured ¹ H-NMR spectrum and chemical shift value, compounds (1-1) and (1-3) to (1) It was confirmed that each of −5) was obtained.

Compound (1-2): ¹ H-NMR (300 MHz, CDCl ₃ ) δ = 7.10-7.21 (m, 3H), 6.99 (s, 1H), 6.68-6.73 (m , 2H), 5.99 (s, 2H), 5.05 (s, 2H), 4.24 (s, 2H), 2.23 (s, 6H).

A compound represented by the following chemical formula (E-1) (hereinafter referred to as compound (E-1)) was also prepared as an electron transport agent used in Comparative Examples.

<Manufacture of photoconductor>
Photoreceptors (A-1) to (A-10) and (B-1) to (B-2) were produced using materials for forming the photosensitive layer.

(Manufacture of photoconductor (A-1))
In the container, 2 parts by mass of an X-type metal-free phthalocyanine as a charge generator, 50 parts by mass of the compound (10-1) as a hole transport agent, 30 parts by mass of the compound (1-1) as an electron transport agent, a binder 100 parts by mass of bisphenol Z-type polycarbonate resin as a resin and 600 parts by mass of tetrahydrofuran as a solvent were added. The contents of the container were mixed for 12 hours using a ball mill to disperse the material in the solvent. This obtained the coating liquid for photosensitive layers. The coating solution for the photosensitive layer was coated on a conductive substrate (aluminum drum-shaped support, diameter 30 mm, total length 238.5 mm) using a blade coating method. The applied photosensitive layer coating solution was dried with hot air at 120 ° C. for 80 minutes. Thus, a single photosensitive layer (thickness 30 μm) was formed on the conductive substrate. As a result, a photoreceptor (A-1) was obtained.

(Production of photoconductors (A-2) to (A-10) and (B-1) to (B-2))
Each of the photoreceptors (A-2) to (A-10) and (B-1) to (B-2) was prepared in the same manner as in the production of the photoreceptor (A-1) except that the following points were changed. Manufactured. In the production of the photoreceptor (A-1), X-type metal-free phthalocyanine was used as a charge generator, but the photoreceptors (A-2) to (A-10) and (B-1) to (B-2) In each production, charge generators of the types shown in Table 2 were used. In the production of the photoreceptor (A-1), the compound (1-1) was used as an electron transfer agent, but the photoreceptors (A-2) to (A-10) and (B-1) to (B-2) In each production of (), electron transport agents of the type shown in Table 2 were used.

<Evaluation of sensitivity characteristics>
The sensitivity characteristics of each of the photoreceptors (A-1) to (A-10) and (B-1) to (B-2) were evaluated. The sensitivity characteristics were evaluated in an environment of a temperature of 23 ° C. and a relative humidity of 50% RH. First, the surface of the photosensitive member was charged to +600 V using a drum sensitivity tester (manufactured by Gentec Corporation). Next, monochromatic light (wavelength 780 nm, half-value width 20 nm, light energy 1.5 μJ / cm ² ) was extracted from the white light of the halogen lamp using a bandpass filter. The surface of the photoreceptor was irradiated with the extracted monochromatic light. The surface potential of the photoconductor was measured after 50 milliseconds had elapsed from the end of irradiation. The measured surface potential was defined as a post-exposure potential (V _L , unit: + V). Table 2 shows the measured post-exposure potential (V _L ) of the photoreceptor. In addition, it shows that the sensitivity characteristic (especially photosensitivity characteristic) of a photoconductor is excellent, so that the post-exposure potential (V _L ) is a small positive value.

<Evaluation of presence or absence of crystallization>
The entire surface (photosensitive layer) of each of the photoreceptors (A-1) to (A-10) and (B-1) to (B-2) was observed with the naked eye. And the presence or absence of the crystallized part in a photosensitive layer was confirmed. The confirmation results are shown in Table 2.

In Table 2, CGM, HTM, ETM, V _L , XH ₂ Pc, and Y-TiOPc are the charge generator, hole transport agent, electron transport agent, post-exposure potential, X-type metal-free phthalocyanine, and Y, respectively. Type titanyl phthalocyanine. In Table 2, “None” indicates that the portion crystallized in the photosensitive layer was not confirmed, and “Slightly crystallized” indicates that the portion crystallized in the photosensitive layer was slightly confirmed.

Photoconductors (A-1) to (A-10) were provided with a conductive substrate and a single photosensitive layer. The photosensitive layer contained at least a charge generator and compound (1). Specifically, the photosensitive layer contained any of compounds (1-1) to (1-5) included in general formula (1). Therefore, as is apparent from Table 2, in the photoreceptors (A-1) to (A-10), the post-exposure potential was a small positive value, and the sensitivity characteristics of the photoreceptor were excellent. In the photoreceptors (A-1) to (A-10), no crystallized portion was confirmed in the photosensitive layer, and crystallization of the photosensitive layer was suppressed.

On the other hand, the photosensitive layers of the photoreceptors (B-1) to (B-2) did not contain the compound (1). Specifically, the photosensitive layers of the photoreceptors (B-1) to (B-2) contained the compound (E-1), but the compound (E-1) is included in the general formula (1). It was not a compound. Therefore, as is apparent from Table 2, in the photoconductors (B-1) to (B-2), the post-exposure potential was a large positive value, and the photoconductor sensitivity characteristics were inferior. In the photoconductors (B-1) to (B-2), a portion crystallized in the photosensitive layer was slightly confirmed, and crystallization of the photosensitive layer was not suppressed.

From the above, it was shown that the photoreceptor according to the present invention is excellent in sensitivity characteristics.

The photoconductor according to the present invention can be used in an image forming apparatus.

Claims

A conductive substrate and a single photosensitive layer;
The photosensitive layer is an electrophotographic photosensitive member containing at least a charge generating agent and a compound represented by the following general formula (1).

(In the general formula (1),
R 1 is an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an aralkyl group having 7 to 20 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, or Represents an aryl group having 6 to 14 carbon atoms which may have at least one substituent, and the substituent is a halogen atom, an alkyl group having 1 to 10 carbon atoms, or 1 to 6 carbon atoms. An alkoxy group, an aralkyl group having 7 to 20 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, or an aryl group having 6 to 14 carbon atoms,
R 2 , R 3 and R 4 are each independently a hydrogen atom, a halogen atom, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, or 7 to 20 carbon atoms. It represents an aralkyl group, a cycloalkyl group having 3 to 10 carbon atoms, or an aryl group having 6 to 14 carbon atoms, and R 3 and R 4 may be bonded to each other to represent a ring. )
In the general formula (1),
R 1 is an alkyl group having 1 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, or at least one alkyl group having 1 to 10 carbon atoms. Represents an aryl group of 6 or more and 14 or less,
R 2 , R 3 and R 4 each independently represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 10 carbon atoms or an alkoxy group having 1 to 6 carbon atoms, and R 3 and R 4 are The electrophotographic photoreceptor according to claim 1, which may be bonded to each other to represent a 5-membered to 7-membered heterocyclic ring.
In the general formula (1), R 1 may have a cycloalkyl group having 3 to 10 carbon atoms, or at least one alkyl group having 1 to 10 carbon atoms. The electrophotographic photosensitive member according to claim 2, which represents the following aryl group.
4. The electrophotographic photosensitive member according to claim 3, wherein, in the general formula (1), R 2 represents a hydrogen atom, and R 3 and R 4 are bonded to each other to represent a 5-membered to 7-membered heterocyclic ring. body.
4. The electrophotographic photosensitive member according to claim 3, wherein in the general formula (1), R 2 and R 3 each represent a hydrogen atom, and R 4 represents a halogen atom.
The compound represented by the general formula (1) is a compound represented by the following chemical formula (1-1), (1-2), (1-3), (1-4) or (1-5). The electrophotographic photosensitive member according to claim 1.
The electrophotographic photoreceptor according to claim 1, wherein the photosensitive layer further contains a compound represented by the following general formula (10).

(In the general formula (10), R 101 , R 102 , R 103 , R 104 , R 105 and R 106 are each independently an alkyl group having 1 to 6 carbon atoms, and having 1 to 6 carbon atoms. Represents an alkoxy group or an aryl group having 6 to 14 carbon atoms,
a, b, c and d each independently represents an integer of 0 to 5,
e and f each independently represents an integer of 0 or more and 4 or less. )
The electrophotographic photosensitive member according to claim 7, wherein the compound represented by the general formula (10) is a compound represented by the following chemical formula (10-1).
The electrophotographic photoreceptor according to claim 1, wherein the photosensitive layer further contains a polycarbonate resin having a repeating unit represented by the following chemical formula (20).