CN112051716B

CN112051716B - Photosensitive body, image forming apparatus, and method for manufacturing photosensitive body

Info

Publication number: CN112051716B
Application number: CN202010487145.4A
Authority: CN
Inventors: 山本骏世; 清水智文; 江连和昭
Original assignee: Kyocera Document Solutions Inc
Current assignee: Kyocera Document Solutions Inc
Priority date: 2019-06-07
Filing date: 2020-06-02
Publication date: 2024-04-23
Anticipated expiration: 2040-06-02
Also published as: CN112051716A; JP2020201342A; JP7310329B2

Abstract

The invention provides a photoreceptor, an image forming apparatus and a method for manufacturing the photoreceptor. The electrophotographic photoreceptor includes a conductive substrate and a photosensitive layer. A single layer of photosensitive layer. The photosensitive layer contains a charge generating agent, a hole transporting agent, an electron transporting agent, and a binder resin. The hole transporting agent contains a first hole transporting agent and a second hole transporting agent. The first hole-transporting agent is a compound represented by the general formula (1). The second hole-transporting agent is a compound represented by the general formula (2). The electron transport agent contains a compound represented by the general formula (10), (11) or (12). [ chemical formula 1 ][ Chemical formula 2]

Description

Photosensitive body, image forming apparatus, and method for manufacturing photosensitive body

Technical Field

The present invention relates to a photoreceptor (electrophotographic photoreceptor), an image forming apparatus, and a method for manufacturing the photoreceptor (electrophotographic photoreceptor).

Background

Electrophotographic photoreceptors are used as image bearing members in electrophotographic image forming apparatuses (e.g., printers or multifunctional integrated machines). The electrophotographic photoreceptor includes a photosensitive layer. Examples of the electrophotographic photoreceptor include a single-layer electrophotographic photoreceptor and a layered electrophotographic photoreceptor. The single-layer electrophotographic photoreceptor includes a single-layer photosensitive layer having a charge generation function and a charge transport function. The photosensitive layer in the laminated electrophotographic photoreceptor contains a charge generation layer having a charge generation function and a charge transport layer having a charge transport function.

For example, an imaging element having a charge transfer layer containing a diamine compound of a specific structure is known.

Disclosure of Invention

However, as a result of the studies by the present inventors, it was found that the above-mentioned imaging element was insufficient in terms of crack resistance and crystallization inhibition.

The present invention has been made in view of the above problems, and an object thereof is to provide an electrophotographic photoreceptor which is excellent in crack resistance and can suppress crystallization. Still another object of the present invention is to provide an image forming apparatus capable of forming a high-quality image with excellent durability by providing the above electrophotographic photoreceptor. Still another object of the present invention is to produce an electrophotographic photoreceptor which realizes simplification of a hole-transporting agent production process, while also having excellent crack resistance and being capable of suppressing crystallization.

An electrophotographic photoreceptor of the present invention includes a conductive substrate and a photosensitive layer. The photosensitive layer is a single layer. The photosensitive layer contains a charge generating agent, a hole transporting agent, an electron transporting agent, and a binder resin. The hole transporting agent contains a first hole transporting agent and a second hole transporting agent. The first hole-transporting agent is a compound represented by the general formula (1). The second hole-transporting agent is a compound represented by the general formula (2). The electron transport agent contains a compound represented by the general formula (10), (11) or (12).

[ Chemical formula 1]

In the general formula (1), R ^1A、R^2A、R^3A、R^4A、R^5A、R^6A、R^7A、R^8A、R^9A and R ^10A each independently represent a hydrogen atom, a C1-C8 alkyl group, a C1-C8 alkoxy group or a C6-C14 aryl group. R ^1B in the general formula (1) and R ^1C in the general formula (2) are the same groups as R ^1A in the general formula (1). R ^2B in the general formula (1) and R ^2C in the general formula (2) are the same groups as R ^2A in the general formula (1). R ^3B in the general formula (1) and R ^3C in the general formula (2) are the same groups as R ^3A in the general formula (1). R ^4B in the general formula (1) and R ^4C in the general formula (2) are the same groups as R ^4A in the general formula (1). R ^5B in the general formula (1) and R ^5C in the general formula (2) are the same groups as R ^5A in the general formula (1). R ^6B in the general formula (1) and R ^6C and R ^6D in the general formula (2) are the same groups as R ^6A in the general formula (1). R ^7B in the general formula (1) and R ^7C and R ^7D in the general formula (2) are the same groups as R ^7A in the general formula (1). R ^8B in the general formula (1) and R ^8C and R ^8D in the general formula (2) are the same groups as R ^8A in the general formula (1). R ^9B in the general formula (1) and R ^9C and R ^9D in the general formula (2) are the same groups as R ^9A in the general formula (1). R ^10B in the general formula (1) and R ^10C and R ^10D in the general formula (2) are the same groups as R ^10A in the general formula (1). Y in the general formula (1) is a divalent group represented by the chemical formula (Y2).

[ Chemical formula 2]

[ Chemical 3]

In the general formula (10), Q ^5A and Q ^5B each independently represent a hydrogen atom, a C1-C8 alkyl group, a phenyl group or a C1-C8 alkoxy group. Q ^6A and Q ^6B each independently represent C1-C8 alkyl, phenyl or C1-C8 alkoxy. m ₁ and m ₂ each independently represent an integer of 0 to 4. In the general formula (11), Q ⁷ and Q ⁸ each independently represent a hydrogen atom, a C1-C8 alkyl group, a phenyl group or a C1-C8 alkoxy group. Q ⁹ represents a C1-C8 alkyl group, a phenyl group or a C1-C8 alkoxy group, and m ₃ represents an integer of 0 to 4 inclusive. In the general formula (12), Q ¹⁰ and Q ¹¹ each independently represent a C1-C6 alkyl group or a hydrogen atom. Q ¹² represents a halogen atom or a hydrogen atom.

An image forming apparatus includes an image carrier, a charging device, an exposure device, a developing device, and a transfer device. The charging device charges a surface of the image carrier to a positive polarity. The exposure device exposes the surface of the charged image carrier, and forms an electrostatic latent image on the surface of the image carrier. The developing device develops the electrostatic latent image into a toner image. The transfer device transfers the toner image from the image bearing member to a transfer target. The image bearing member is the above-described electrophotographic photoreceptor.

The method for producing an electrophotographic photoreceptor of the present invention comprises a hole-transporting agent production step and a photosensitive layer formation step. In the hole-transporting agent production step, the hole-transporting agent is produced. In the photosensitive layer forming step, a coating liquid containing the charge generating agent, the hole transporting agent, the electron transporting agent, the binder resin, and a solvent is applied to the conductive substrate, and at least a part of the solvent contained in the coating liquid is removed, thereby forming the photosensitive layer. The hole-transporting agent production process includes a first stirring process and a second stirring process. In the first stirring step, a mixed solution containing the compound represented by the general formula (A) and the compound represented by the general formula (B) is first stirred. In the second stirring step, a compound represented by the general formula (C) is further added to the mixed solution, and the mixed solution is subjected to second stirring. After the first stirring step, the second stirring step is performed without purifying the mixed solution. And obtaining the hole transporting agent containing the first hole transporting agent and the second hole transporting agent after the first stirring process and the second stirring process.

[ Chemical formula 4]

R ¹、R²、R³、R⁴ and R ⁵ in the general formula (A) are the same groups as R ^1A、R^2A、R^3A、R4^A and R ^5A in the general formula (1), respectively. R ⁶、R⁷、R⁸、R⁹ and R ¹⁰ in the general formula (B) are the same groups as R ^6A、R^7A、R^8A、R^9A and R ^10A in the general formula (1), respectively. Z ¹ in the general formula (B) represents a halogen atom. Y in the general formula (C) is the same group as Y in the general formula (1). Z ² and Z ³ in the general formula (C) represent halogen atoms.

The electrophotographic photoreceptor of the present invention has excellent crack resistance and can suppress crystallization. Further, the image forming apparatus of the present invention has an electrophotographic photoreceptor which is excellent in crack resistance and can suppress crystallization, and therefore is excellent in durability and capable of forming a high-quality image. Further, according to the method for producing a photoreceptor of the present invention, it is possible to produce a photoreceptor excellent in crack resistance and capable of suppressing crystallization while simplifying the hole-transporting agent production process.

Drawings

Fig. 1 is a partial cross-sectional view of an electrophotographic photoreceptor according to an embodiment of the present invention.

Fig. 2 is a partial cross-sectional view of an electrophotographic photoreceptor according to an embodiment of the present invention.

Fig. 3 is a partial cross-sectional view of an electrophotographic photoreceptor according to an embodiment of the present invention.

Fig. 4 is a cross-sectional view of an example of an image forming apparatus.

Detailed Description

Hereinafter, embodiments of the present invention will be described in detail. However, the present invention is not limited to the following embodiments in any way. The present invention can be implemented after being appropriately modified within the scope of the object. In addition, although the overlapping description is omitted appropriately, the gist of the present invention is not limited in some cases. Hereinafter, the compound and its derivatives may be collectively referred to by the name of the compound followed by the "class". In addition, in the case where a compound name is followed by a "class" to indicate a polymer name, it means that the repeating unit of the polymer is derived from the compound or a derivative thereof.

First, substituents used in the present specification will be described. Examples of the halogen atom (halogen group) include: fluorine atom (fluoro group), chlorine atom (chloro group), bromine atom (bromo group) and iodine atom (iodo group).

Unless otherwise indicated, C1-C8 alkyl, C1-C6 alkyl, C1-C4 alkyl, C2-C4 alkyl are all linear or branched and are unsubstituted. Examples of the C1-C8 alkyl group include: methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, tert-butyl, n-pentyl, 1-methylbutyl, 2-methylbutyl, 3-methylbutyl, 1-ethylpropyl, 2-ethylpropyl, 1-dimethylpropyl, 1, 2-dimethylpropyl, 2-dimethylpropyl, 1, 2-dimethylpropyl, n-hexyl, 1-methylpentyl, 2-methylpentyl, 3-methylpentyl 4-methylpentyl, 1-dimethylbutyl, 1, 2-dimethylbutyl, 1, 3-dimethylbutyl, 2-dimethylbutyl, 2, 3-dimethylbutyl, 3-dimethylbutyl, 1, 2-trimethylpropyl, 1, 2-trimethylpropyl, 1-ethylbutyl, 2-ethylbutyl and 3-ethylbutyl, linear and branched heptyl and linear and branched octyl. Examples of C1-C6 alkyl, C1-C4 alkyl, C2-C4 alkyl are groups having the corresponding number of carbon atoms in the case of C1-C8 alkyl, respectively.

Unless otherwise indicated, C1-C8 alkoxy, C1-C6 alkoxy and C1-C3 alkoxy are all linear or branched and unsubstituted. Examples of the C1-C8 alkoxy group include: methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, sec-butoxy, tert-butoxy, n-pentoxy, 1-methylbutoxy, 2-methylbutoxy, 3-methylbutoxy, 1-ethylpropoxy, 2-ethylpropoxy, 1-dimethylpropoxy, 1, 2-dimethylpropoxy, 2-dimethylpropoxy, 1, 2-dimethylpropoxy, n-hexyloxy, 1-methylpentyloxy, 2-methylpentyloxy 3-methylpentyloxy, 4-methylpentyloxy, 1-dimethylbutoxy, 1, 2-dimethylbutoxy, 1, 3-dimethylbutoxy, 2-dimethylbutoxy, 2, 3-dimethylbutoxy, 3-dimethylbutoxy, 1, 2-trimethylpropoxy, 1, 2-trimethylpropoxy, 1-ethylbutoxy, 2-ethylbutoxy, 3-ethylbutoxy, linear and branched heptyloxy and linear and branched octyloxy groups. Examples of C1-C6 alkoxy and C1-C3 alkoxy are, respectively, groups having the corresponding number of carbon atoms in the case of C1-C8 alkoxy.

Unless otherwise indicated, both C6-C14 aryl and C6-C10 aryl are unsubstituted. Examples of the C6-C14 aryl group include: phenyl, naphthyl, indacenyl (indacenyl), biphenylene (biphenylenyl), acenaphthylene (ACENAPHTHYLENYL), anthryl and phenanthryl. Examples of the C6-C10 aryl group include: phenyl and naphthyl. As described above, substituents used in the present specification are described.

< Electrophotographic photoreceptor >

The present embodiment relates to an electrophotographic photoreceptor (hereinafter, may be referred to as a photoreceptor). Hereinafter, a photoreceptor 1 according to the present embodiment will be described with reference to fig. 1 to 3. Fig. 1 to 3 are partial sectional views of the photoreceptor 1.

As shown in fig. 1, the photoreceptor 1 includes, for example, a conductive substrate 2 and a photosensitive layer 3. A single layer of photosensitive layer 3. The photoreceptor 1 is a single-layer electrophotographic photoreceptor having a single-layer photosensitive layer 3.

As shown in fig. 2, the photoreceptor 1 may include a conductive substrate 2, a photosensitive layer 3, and an intermediate layer 4 (undercoat layer). The intermediate layer 4 is between the conductive substrate 2 and the photosensitive layer 3. As shown in fig. 1, the photosensitive layer 3 may be directly on the conductive substrate 2. Alternatively, as shown in fig. 2, the photosensitive layer 3 may be formed on the conductive substrate 2 through the intermediate layer 4.

As shown in fig. 3, the photoreceptor 1 may include a conductive substrate 2, a photosensitive layer 3, and a protective layer 5. A protective layer 5 is on the photosensitive layer 3. As shown in fig. 1 and 2, the photosensitive layer 3 is preferably used as the outermost surface layer of the photosensitive body 1. By using the photosensitive layer 3 containing a predetermined hole transporting agent and a predetermined electron transporting agent, which will be described later, as the outermost surface layer, even if a cleaning agent remains on the surface of the photosensitive body 1 during maintenance, cracking of the photosensitive layer 3 is less likely to occur. In addition, as shown in fig. 3, the protective layer 5 may also be the outermost surface layer of the photoconductor 1.

The photosensitive layer 3 contains at least a charge generating agent, a hole transporting agent, an electron transporting agent, and a binder resin. The photosensitive layer 3 may further contain an additive as required.

The thickness of the photosensitive layer 3 is not particularly limited, but is preferably 5 μm or more and 100 μm or less, and more preferably 10 μm or more and 50 μm or less. As described above, the photoreceptor 1 is described with reference to fig. 1 to 3.

(Charge generating agent)

Examples of the charge generating agent include: phthalocyanine pigments, perylene pigments, disazo pigments, trisazo pigments, dithiopyr-rolopyrrole (dithioketo-pyrrolopyrrole) pigments, metal-free naphthalocyanine pigments, metal naphthalocyanine pigments, squaraine pigments, indigo pigments, gan Julan pigments, cyanine pigments, powders of inorganic photoconductive materials (for example, selenium-tellurium, selenium-arsenic, cadmium sulfide and amorphous silicon), pyran pigments, anthanthrone pigments, triphenylmethane pigments, petrolatum pigments, toluamide pigments, pyrazoline pigments and quinacridone pigments. The photosensitive layer may contain only 1 kind of charge generating agent, or may contain 2 or more kinds.

The phthalocyanine pigment is a pigment having a phthalocyanine structure. Examples of the phthalocyanine pigment include: no metal phthalocyanine and no metal phthalocyanine. Examples of the metal phthalocyanine include: oxytitanium phthalocyanine, hydroxygallium phthalocyanine and chlorogallium phthalocyanine. The metal-free phthalocyanine is represented by the chemical formula (CGM-1). Oxytitanium phthalocyanine is represented by the chemical formula (CGM-2).

[ Chemical 5]

The phthalocyanine pigment may be crystalline or amorphous. Examples of the metal-free phthalocyanine crystal include: x-type crystals of metal-free phthalocyanine (hereinafter, may be referred to as X-type metal-free phthalocyanine). Examples of the crystal of oxytitanium phthalocyanine include: alpha, beta and Y-type crystals of oxytitanium phthalocyanine (hereinafter, sometimes referred to as alpha, beta and Y-type oxytitanium phthalocyanine, respectively).

For example, in a digital optical image forming apparatus (for example, a laser printer or a facsimile machine using a light source such as a semiconductor laser), a photoreceptor having sensitivity in a wavelength region of 700nm or more is preferably used. The charge generating agent is preferably a phthalocyanine pigment, more preferably a metal-free phthalocyanine or oxytitanium phthalocyanine, further preferably oxytitanium phthalocyanine, particularly preferably Y-type oxytitanium phthalocyanine, from the viewpoint of having a high quantum yield in a wavelength region of 700nm or more.

Y-type oxytitanium phthalocyanine has a main peak in the cukα characteristic X-ray diffraction spectrum, for example, at 27.2 ° of bragg angle (2θ±0.2°). The main peak in the cukα characteristic X-ray diffraction spectrum means a peak having the first or second largest intensity in a range where the bragg angle (2θ±0.2°) is 3 ° to 40 °. In the characteristic X-ray diffraction spectrum of CuK alpha, the Y-type oxytitanium phthalocyanine has no peak at 26.2 ℃.

The cukα characteristic X-ray diffraction spectrum can be measured, for example, by the following method. First, a sample (oxytitanium phthalocyanine) was filled into a sample holder of an X-ray diffraction apparatus (manufactured by Rigaku Corporation under the trade name "RINT (Japanese registered trademark) 1100"), and X-ray wavelengths characteristic of X-ray tube Cu, tube voltage 40kV, tube current 30mA, and CuK. Alpha. Were measuredAnd (3) measuring an X-ray diffraction spectrum. The measurement range (2θ) is, for example, 3 ° or more and 40 ° or less (start angle 3 °, stop angle 40 °), and the scanning speed is, for example, 10 °/minute. And determining a main peak according to the obtained X-ray diffraction spectrum, and reading the Bragg angle of the main peak.

The content of the charge generating agent is preferably 0.1 part by mass or more and 50 parts by mass or less, more preferably 0.5 part by mass or more and 5 parts by mass or less, relative to 100 parts by mass of the binder resin.

(Hole transporting agent)

The hole transporting agent contains a first hole transporting agent and a second hole transporting agent. The first hole-transporting agent is a compound represented by the general formula (1). The second hole-transporting agent is a compound represented by the general formula (2). Hereinafter, the compounds represented by the general formulae (1) and (2) are sometimes referred to as hole transporting agents (1) and (2), respectively.

[ 6] A method for producing a polypeptide

[ Chemical 7]

By containing both the hole transporting agents (1) and (2) in the photosensitive layer, the crack resistance of the photoreceptor can be provided, and crystallization of the photoreceptor can be suppressed. The cracking resistance of the photoreceptor refers to the following characteristics: even if the cleaning agent remains on the surface of the photoreceptor 1 during maintenance, cracking of the photosensitive layer 3 can be suppressed. Wherein the hole transporting agent (2) is a by-product generated during the synthesis of the hole transporting agent (1) as a final product. Generally, the byproducts are removed by purification, thereby obtaining the final product. However, the inventors found that the crack resistance of the photoreceptor is improved when the hole transporting agent (2) is intentionally mixed into the hole transporting agent (1) without completely removing the hole transporting agent (2) as a by-product by purification. The inventors have found that the hole transporter (2) inhibits aggregation of the hole transporter (1), and that crystallization of the photoreceptor is inhibited. The photoreceptor of the present embodiment has a photosensitive layer having excellent photosensitivity and containing a hole transporting agent (1). Therefore, the cracking resistance of the photoreceptor can be improved and the crystallization of the photoreceptor can be suppressed without impairing the sensitivity characteristics of the photoreceptor.

The C1-C8 alkyl group represented by R ^1A、R^2A、R^3A、R^4A、R^5A、R^6A、R^7A、R^8A、R^9A and R ^10A in the general formula (1) is preferably a C1-C6 alkyl group, more preferably a C1-C3 alkyl group, further preferably a methyl group or an ethyl group.

The C1-C8 alkoxy group represented by R ^1A、R^2A、R^3A、R^4A、R^5A、R^6A、R^7A、R^8A、R^9A and R ^10A in the general formula (1) is preferably a C1-C6 alkoxy group, more preferably a C1-C3 alkoxy group, and further preferably a methoxy group.

The C6-C14 aryl group represented by R ^1A、R^2A、R^3A、R^4A、R^5A、R^6A、R^7A、R^8A、R^9A and R ^10A in the general formula (1) is preferably a C6-C10 aryl group.

In order to improve the cracking resistance of the photoreceptor and to suppress crystallization, it is preferable to: in the general formula (1), at least 2 of R ^1A、R^2A、R^3A、R^4A、R^5A、R^6A、R^7A、R^8A、R^9A and R ^10A represent groups other than a hydrogen atom, and the rest of R ^1A、R^2A、R^3A、R^4A、R^5A、R^6A、R^7A、R^8A、R^9A and R ^10A represent a hydrogen atom. The total number of carbon atoms of the groups other than hydrogen atoms is preferably 3 or more. In the general formula (1), the groups other than the hydrogen atom represented by R ^1A、R^2A、R^3A、R^4A、R^5A、R^6A、R^7A、R^8A、R^9A and R ^10A are a C1-C8 alkyl group, a C1-C8 alkoxy group or a C6-C14 aryl group.

In the general formula (1), R ^3A preferably represents a C1-C8 alkoxy group in order to improve the cracking resistance of the photoreceptor and to suppress crystallization.

In order to improve the cracking resistance of the photoreceptor and to suppress crystallization, it is preferable to: in the general formula (1), 1 or 2 of R ^1A、R^3A and R ^5A represent a C1-C8 alkyl group or a C1-C8 alkoxy group, the remainder of R ^1A、R^3A and R ^5A represent a hydrogen atom, and R ^2A and R ^4A both represent a hydrogen atom.

In order to improve the cracking resistance of the photoreceptor and to suppress crystallization, it is preferable to: in the general formula (1), R ^8A represents a hydrogen atom or a C1-C8 alkyl group, and R ^6A、R^7A、R^9A and R ^10A represent hydrogen atoms.

In order to improve the cracking resistance of the photoreceptor and to suppress crystallization, it is preferable to: thehole-transportingagent(1)isacompoundrepresentedbytheformula(HTM-1),andthehole-transportingagent(2)isacompoundrepresentedbytheformula(HTM-A). Based on the same considerations, preference is given to: the hole transporting agent (1) is a compound represented by the formula (HTM-2), and the hole transporting agent (2) is a compound represented by the formula (HTM-B). Based on the same considerations, preference is given to: the hole-transporting agent (1) is a compound represented by the formula (HTM-3), and the hole-transporting agent (2) is a compound represented by the formula (HTM-C). Based on the same considerations, preference is given to: the hole-transporting agent (1) is a compound represented by the formula (HTM-4), and the hole-transporting agent (2) is a compound represented by the formula (HTM-D). The compounds represented by the chemical formulas (HTM-1) to (HTM-4) are sometimes referred to as hole-transporting agents (HTM-1) to (HTM-4), respectively. thecompoundsrepresentedbythechemicalformulas(HTM-A)to(HTM-D)aresometimesreferredtoashole-transportingagents(HTM-A)to(HTM-D),respectively.

[ Chemical formula 8]

The content of the hole-transporting agent (2) is preferably 1.0 mass% or more and 30.0 mass% or less, more preferably 1.0 mass% or more and 10.0 mass% or less, and still more preferably 2.0 mass% or more and 5.0 mass% or less, relative to the total mass of the hole-transporting agents (1) and (2). When the content of the hole-transporting agent (2) is 1.0 mass% or more relative to the total mass of the hole-transporting agents (1) and (2), the crack resistance of the photoreceptor can be further improved, and the crystallization of the photoreceptor can be further suppressed. When the content of the hole transporting agent (2) is 30.0 mass% or less relative to the total mass of the hole transporting agents (1) and (2), the photosensitivity of the photoreceptor can be improved. The method of adjusting the content of the hole-transporting agent (2) with respect to the total mass of the hole-transporting agents (1) and (2) will be described in the following < method of producing a photoreceptor >.

The total content of the hole-transporting agents (1) and (2) is preferably 10 parts by mass or more and 200 parts by mass or less, more preferably 50 parts by mass or more and 90 parts by mass or less, and still more preferably 60 parts by mass or more and 80 parts by mass or less, with respect to 100 parts by mass of the binder resin.

The hole transporting agent may contain only the hole transporting agents (1) and (2) in the photosensitive layer. Alternatively, the hole-transporting agent may further contain a hole-transporting agent other than the hole-transporting agents (1) and (2) (hereinafter, sometimes referred to as other hole-transporting agents) in addition to the hole-transporting agents. Other hole-transporting agents are, for example: triphenylamine derivatives, diamine derivatives (e.g., N, N, N ', N' -tetraphenylbenzidine derivatives, N, N, N ', N' -tetraphenylphenylenediamine derivatives, N, N, N ', N' -tetraphenylnaphthylenediamine derivatives, N, N, N ', N' -tetraphenylphenanthrylenediamine (N, N, N ', N' -TETRAPHENYL PHENANTHRYLENE DIAMINE) derivatives and di (aminophenylvinyl) benzene derivatives), oxadiazoles (e.g., 2, 5-bis (4-methylaminophenyl) -1,3, 4-oxadiazole), styrenes (e.g., 9- (4-diethylaminostyryl) anthracene), carbazole compounds (e.g., polyvinylcarbazole), organopolysiloxane compounds, pyrazoline compounds (e.g., 1-phenyl-3- (p-dimethylaminophenyl) pyrazoline), hydrazone compounds, indole compounds, oxazole compounds, isoxazole compounds, thiazole compounds, thiadiazole compounds, imidazole compounds, pyrazole compounds and triazole compounds.

(Electron transporting agent)

The electron transporting agent contains a compound represented by the general formula (10), (11) or (12) (hereinafter, may be referred to as the electron transporting agent (10), (11) or (12), respectively). By containing both the hole transporting agents (1) and (2) and the electron transporting agent (10), (11) or (12) in the photosensitive layer, the cracking resistance of the photoreceptor can be improved and the crystallization of the photoreceptor can be suppressed in particular.

[ Chemical formula 9]

In the general formula (10), Q ^5A and Q ^5B each independently represent a hydrogen atom, a C1-C8 alkyl group, a phenyl group or a C1-C8 alkoxy group. Q ^6A and Q ^6B each independently represent C1-C8 alkyl, phenyl or C1-C8 alkoxy. m ₁ and m ₂ each independently represent an integer of 0 to 4.

When m ₁ represents an integer of 2 to 4, Q ^6A may be the same as or different from each other. When m ₂ represents an integer of 2 to 4, Q ^6B may be the same as or different from each other.

In the general formula (10), Q ^5A and Q ^5B are each independently preferably a C1-C8 alkyl group, more preferably a C1-C6 alkyl group, and still more preferably a1, 1-dimethylpropyl group. m ₁ and m ₂ are preferably 0.

In the general formula (11), Q ⁷ and Q ⁸ each independently represent a hydrogen atom, a C1-C8 alkyl group, a phenyl group or a C1-C8 alkoxy group. Q ⁹ represents C1-C8 alkyl, phenyl or C1-C8 alkoxy. m ₃ represents an integer of 0 to 4 inclusive.

When m ₃ represents an integer of 2 to 4, Q ⁹ may be the same as or different from each other.

In the general formula (11), Q ⁷ and Q ⁸ are each independently preferably a C1-C8 alkyl group, more preferably a C1-C6 alkyl group, and still more preferably a tert-butyl group. m ₃ preferably represents 0.

In the general formula (12), Q ¹⁰ and Q ¹¹ each independently represent a C1-C6 alkyl group or a hydrogen atom. Q ¹² represents a halogen atom or a hydrogen atom.

In the general formula (12), Q ¹⁰ and Q ¹¹ are each independently preferably a C1-C6 alkyl group, more preferably a tert-butyl group. Q ¹² preferably represents a halogen atom, more preferably represents a chlorine atom.

In order to improve the cracking resistance of the photoreceptor and to suppress crystallization, the electron mediator (10) is preferably a compound represented by the formula (E-1). The electron mediator (11) is preferably a compound represented by the formula (E-2) in view of the same. For the same reasons, the electron mediator (12) is preferably a compound represented by the formula (E-3). The compounds represented by the chemical formulas (E-1), (E-2) and (E-3) are sometimes referred to as electron transporting agents (E-1), (E-2) and (E-3), respectively.

[ Chemical formula 10]

The content of the electron mediator is preferably 5 parts by mass to 150 parts by mass, more preferably 10 parts by mass to 50 parts by mass, and even more preferably 20 parts by mass to 40 parts by mass, based on 100 parts by mass of the binder resin.

The photosensitive layer may contain only 1 electron transporting agent or may contain 2 or more electron transporting agents. The photosensitive layer may further contain an electron transport agent other than the electron transport agents (10), (11) and (12) (hereinafter, may be referred to as other electron transport agents). Other electron transport agents are, for example: quinone compounds, diimide compounds, hydrazone compounds, malononitrile compounds, thiopyran compounds, trinitrothioxanthone compounds, 3,4,5, 7-tetranitro-9-fluorenone compounds, dinitroanthracene compounds, dinitroacridine compounds, tetracyanoethylene, 2,4, 8-trinitrothioxanthone, dinitrobenzene, dinitroacridine, succinic anhydride, maleic anhydride and dibromomaleic anhydride. Examples of the quinone compound include: diphenoquinone compounds, azo quinone compounds, anthraquinone compounds, naphthoquinone compounds, nitroanthraquinone compounds and dinitroanthraquinone compounds.

(Adhesive resin)

The binder resin includes, for example: thermoplastic resins, thermosetting resins, and photocurable resins. Examples of the thermoplastic resin include: polyarylate resin, polycarbonate resin, styrene-butadiene copolymer, styrene-acrylonitrile copolymer, styrene-maleic acid copolymer, acrylic 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, polyurethane resin, polysulfone resin, diallyl phthalate resin, ketone resin, polyvinyl butyral resin, polyester resin, polyvinyl acetal resin, and polyether resin. Examples of the thermosetting resin include: silicone resins, epoxy resins, phenolic resins, urea resins, and melamine resins. Examples of the photocurable resin include: acrylic acid adducts of epoxy compounds and acrylic acid adducts of polyurethane compounds. The photosensitive layer may contain only 1 kind of binder resin, or may contain 2 or more kinds of binder resins.

The viscosity average molecular weight of the binder resin is preferably 10,000 or more, more preferably 20,000 or more, further preferably 30,000 or more, and particularly preferably 40,000 or more. When the viscosity average molecular weight of the binder resin is 10,000 or more, the abrasion resistance of the photoreceptor can be improved. On the other hand, the viscosity average molecular weight of the binder resin is preferably 80,000 or less, more preferably 70,000 or less. When the viscosity average molecular weight of the binder resin is 80,000 or less, the binder resin is easily dissolved in a solvent for forming a photosensitive layer.

The binder resin is preferably a polyarylate resin or a polycarbonate resin, and more preferably a polyarylate resin. The polyarylate resin and the polycarbonate resin will be described in order.

First, a polyarylate resin will be described. In order to further improve the crack resistance of the photoreceptor and suppress crystallization, preferable examples of the polyarylate resin are, for example: a polyarylate resin comprising at least 1 repeating unit represented by the general formula (10) and at least 1 repeating unit represented by the general formula (11). Hereinafter, a polyarylate resin containing at least 1 repeating unit represented by the general formula (10) and at least 1 repeating unit represented by the general formula (11) is sometimes described as a polyarylate resin (PA). The repeating units represented by the general formulae (10) and (11) are sometimes referred to as repeating units (10) and (11), respectively.

[ Chemical formula 11]

In the general formula (10), R ¹¹ and R ¹² each independently represent a hydrogen atom or a methyl group. In the general formula (10), W is a divalent group represented by the general formula (W1), the general formula (W2) or the chemical formula (W3).

[ Chemical formula 12]

In the general formula (W1), R ¹³ represents a hydrogen atom or a C1-C4 alkyl group, and R ¹⁴ represents a C1-C4 alkyl group. In the general formula (W2), t represents an integer of 1 to 3.

In the general formula (11), X is a divalent group represented by the formula (X1), the formula (X2), or the formula (X3).

[ Chemical formula 13]

The C1-C4 alkyl group represented by R ¹³ in the general formula (W1) is preferably methyl. The C1-C4 alkyl group represented by R ¹⁴ in the general formula (W1) is preferably a C2-C4 alkyl group, more preferably an ethyl group. T in the general formula (W2) is preferably 2.

In the general formula (10), R ¹¹ and R ¹² are preferably methyl groups. In the general formula (10), W is preferably a divalent group represented by the general formula (W2). In the general formula (11), X is preferably a divalent group represented by the chemical formulas (X1) and (X3).

Preferred examples of the repeating unit (10) include: repeating units represented by the chemical formulas (10-1), (10-2) and (10-3). Hereinafter, the repeating units represented by the chemical formulas (10-1), (10-2) and (10-3) are sometimes referred to as repeating units (10-1), (10-2) and (10-3), respectively.

[ Chemical formula 14]

Preferred examples of the repeating unit (11) include: repeating units represented by the chemical formulas (11-X1), (11-X2) and (11-X3). Hereinafter, the repeating units represented by the chemical formulas (11-X1), (11-X2) and (11-X3) are sometimes referred to as repeating units (11-X1), (11-X2) and (11-X3), respectively.

[ 15] A method of producing a polypeptide

The polyarylate resin (PA) may contain only 1 kind of repeating unit (10), or may contain 2 or more kinds of repeating units (10). The polyarylate resin (PA) may contain only 1 kind of repeating unit (11), or may contain 2 or more kinds of repeating units (11). The polyarylate resin (PA) preferably contains at least 1 repeating unit (10) and at least 2 repeating units (11), more preferably contains 1 repeating unit (10) and 2 repeating units (11).

Preferable examples of the polyarylate resin (PA) include: polyarylate resins containing repeating units (10-2), (11-X1) and (11-X3) (hereinafter, may be referred to as polyarylate resins (I)).

Further preferable examples of the polyarylate resin (PA) are: the polyarylate resin represented by the chemical formula (R-1) (hereinafter, may be referred to as polyarylate resin (R-1)). In addition, in the chemical formula (R-1), the right subscript number of each repeating unit indicates: the percentage (%) of the number of each repeating unit relative to the total number of repeating units contained in the polyarylate resin. The total number of repeating units is the sum of the number of repeating units derived from bisphenol and the number of repeating units derived from dicarboxylic acid.

[ 16] The preparation method

The polyarylate resin (PA) may be, for example, a random copolymer, an alternating copolymer, a periodic copolymer, or a block copolymer. In the polyarylate resin (PA), the arrangement of the repeating units is not particularly limited as long as the repeating units derived from bisphenol are adjacent to and bonded to the repeating units derived from dicarboxylic acid. The repeating unit derived from bisphenol is, for example, the repeating unit (10). The repeating unit derived from a dicarboxylic acid is, for example, the repeating unit (11).

In the polyarylate resin (PA), the repeating units may be only the repeating units (10) and (11). Or the polyarylate resin (PA), the repeating units (10) and (11) may further contain repeating units other than these repeating units.

The method for producing the polyarylate resin (PA) is not particularly limited. The method for producing the polyarylate resin (PA) is, for example: a method of polycondensing bisphenol (constituting a repeating unit derived from bisphenol) with dicarboxylic acid (constituting a repeating unit derived from dicarboxylic acid). The polycondensation may be by well-known synthetic methods (e.g., solution polymerization, melt polymerization, or interfacial polymerization).

Examples of bisphenols (for constituting the repeating unit derived from bisphenol) include: a compound represented by the general formula (BP-10). Examples of dicarboxylic acids (for constituting the repeating units derived from dicarboxylic acids) include: a compound represented by the formula (DC-11). R ¹¹、R¹², W and X in the general formulae (BP-10) and (DC-11) have the same meanings as R ¹¹、R¹², W and X in the general formulae (10) and (11), respectively.

[ Chemical formula 17]

Bisphenol (used to constitute the repeating units derived from bisphenol) may also be used as the derivatized aromatic diacetate. Dicarboxylic acids (used to constitute the repeating units derived from dicarboxylic acids) may also be used as derivatives. Examples of derivatives of dicarboxylic acids are: dicarboxylic acid dichlorides, dimethyl dicarboxylic acid esters, diethyl dicarboxylic acids and dicarboxylic acid anhydrides. Dicarboxylic acid dichlorides are compounds in which the 2 "-C (=o) -OH" groups of the dicarboxylic acid are each substituted with a "-C (=o) -Cl" group.

In polycondensation of bisphenol and dicarboxylic acid, one or both of a base and a catalyst may be added. An example of a base is sodium hydroxide. Examples of catalysts are: benzyl tributyl ammonium chloride, ammonium bromide, quaternary ammonium salts, triethylamine and trimethylamine. As described above, the polyarylate resin is illustrated.

Next, a polycarbonate resin will be described. Examples of polycarbonate resins are: 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 has a repeating unit represented by the formula (R-2). Hereinafter, the polycarbonate resin having the repeating unit represented by the formula (R-2) may be referred to as a polycarbonate resin (R-2). As described above, the polycarbonate resin is described.

[ Chemical formula 18]

(Additive)

Examples of additives are: ultraviolet light absorbers, antioxidants, radical scavengers, singlet quenchers, softeners, surface modifiers, extenders, thickeners, dispersion stabilizers, waxes, donors, surfactants, plasticizers, sensitizers, electron acceptor compounds and leveling agents.

(Combination of materials)

In order to improve the cracking resistance of the photoreceptor and to suppress crystallization, the combination of the hole transporting agents (1) and (2) and the electron transporting agent is preferably each of combinations No. F-1 to F-8 in Table 1. Based on the same considerations, more preferred are: the combination of the hole transporting agents (1) and (2) and the electron transporting agent is each of combinations No. F-1 to F-8 in Table 1, and the charge generating agent is Y-type oxytitanium phthalocyanine.

[ Table 1]

No.	HTM(1)	HTM(2)	ETM
				F-1	HTM-1	HTM-A	E-1
F-2	HTM-1	HTM-A	E-2
				F-3	HTM-1	HTM-A	E-3
F-4	HTM-2	HTM-B	E-1
				F-5	HTM-2	HTM-B	E-2
F-6	HTM-2	HTM-B	E-3
				F-7	HTM-3	HTM-C	E-1
F-8	HTM-4	HTM-D	E-1

In order to improve the cracking resistance of the photoreceptor and to suppress crystallization, the combination of the hole transporting agents (1) and (2), the electron transporting agent, and the binder resin is preferably each of combinations No. G-1 to G-17 in Table 2. Based on the same considerations, more preferred are: the combination of the hole transporting agents (1) and (2), the electron transporting agent and the binder resin is each of combinations No. G-1 to G-17 in Table 2, and the charge generating agent is Y-type oxytitanium phthalocyanine.

[ Table 2]

In tables 1 and 2, the "No." is a combination No. "HTM (1)" is a hole transporter (1), "HTM (2)" is a hole transporter (2), "ETM" is an electron transporter, and "resin" is a binder resin. The "I" of the "resin" column is a polyarylate resin (I). The column "R-1" of the "resin" is a polyarylate resin (R-1). The column "R-2" of the "resin" is a polycarbonate resin (R-2).

(Conductive matrix)

The conductive substrate is not particularly limited as long as it can be used as a conductive substrate of a photoreceptor. The conductive base may be formed of a conductive material at least on the surface portion. An example of a conductive matrix is: a conductive base body made of a conductive material. Another example of a conductive matrix 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 2 or more (for example, as an alloy). Among these conductive materials, aluminum and aluminum alloys are preferable from the viewpoint of good charge transfer from the photosensitive layer to the conductive substrate.

The shape of the conductive substrate is appropriately selected according to the structure of the image forming apparatus. The shape of the conductive substrate is, for example: sheet-like and drum-like. The thickness of the conductive substrate is appropriately selected according to the shape of the conductive substrate.

(Intermediate layer)

The intermediate layer (primer layer) contains, for example, inorganic particles and a resin used in the intermediate layer (resin for intermediate layer). It can be considered that: the presence of the intermediate layer can maintain an insulating state to such an extent that occurrence of leakage can be suppressed, and can smoothly flow a current generated when exposing the photoreceptor, thereby suppressing an increase in resistance.

Examples of the inorganic particles include: particles of metals (e.g., aluminum, iron, and copper), particles of metal oxides (e.g., titanium dioxide, aluminum oxide, zirconium oxide, tin oxide, and zinc oxide), and particles of non-metal oxides (e.g., silicon dioxide). These inorganic particles may be used alone or in combination of 2 or more.

Examples of the resin for the intermediate layer are the same as those of the above-described binder resin. In order to well form the intermediate layer and the photosensitive layer, the resin for the intermediate layer is preferably different from the binder resin contained in the photosensitive layer. The intermediate layer may also contain additives. Examples of the additive contained in the intermediate layer are the same as those contained in the photosensitive layer.

< Method for producing photoreceptor >

The method for producing a photoreceptor includes a hole-transporting agent production step and a photosensitive layer formation step.

(Hole transporter manufacturing Process)

In the hole-transporting agent production step, a hole-transporting agent is produced. The hole-transporting agent production process includes a first stirring process and a second stirring process. In the first stirring step, the mixed solution (hereinafter, may be abbreviated as "solution") is first stirred. The solution contains a compound represented by the general formula (A) and a compound represented by the general formula (B). In the second stirring step, the compound represented by the general formula (C) is further added to the solution obtained in the first stirring step, and the solution is subjected to second stirring. After the first stirring step, the second stirring step is performed without purifying the solution. The first stirring step and the second stirring step are performed to obtain a hole transporting agent (i.e., a mixture of hole transporting agents (1) and (2)) containing both the first hole transporting agent and the second hole transporting agent. The resultant mixture of the hole-transporting agents (1) and (2) is used as a hole-transporting agent in the photosensitive layer forming step. The compounds represented by the general formulae (A), (B) and (C) are sometimes referred to as compounds (A), (B) and (C), respectively.

[ Chemical formula 19]

As shown in the following reaction equation (r-1), 1 molar equivalent of the hole transporting agent (2) was obtained by reacting 1 molar equivalent of the compound (A) with 2 molar equivalents of the compound (B). In the first stirring step, a reaction represented by the reaction equation (r-1) is performed. In addition, not only the first stirring step but also the second stirring step may be performed in the reaction represented by the reaction equation (r-1).

[ Chemical formula 20]

As shown in the following reaction equations (r-2) and (r-3), 2 molar equivalents of the compound (A), 2 molar equivalents of the compound (B) and 1 molar equivalent of the compound (C) were reacted to obtain 1 molar equivalent of the hole transporting agent (1). Specifically, as shown in the reaction equation (r-2), 2 molar equivalents of the compound (a) and 2 molar equivalents of the compound (B) are reacted to obtain 2 molar equivalents of the compound represented by the formula (D) (hereinafter, may be referred to as compound (D)). The compound (D) is an intermediate product. Then, as shown in the reaction equation (r-3), 1 molar equivalent of the hole transporting agent (1) was obtained by reacting 2 molar equivalents of the compound (D) with 1 molar equivalent of the compound (C). In the first stirring step, the reaction represented by the reaction equation (r-2) is performed, and in the second stirring step, the reaction represented by the reaction equation (r-3) is performed. In addition, not only the first stirring step but also the second stirring step may be performed in the reaction represented by the reaction equation (r-2).

[ Chemical formula 21]

In the raw materials of the hole transporting agents (1) and (2), the compound (a) is common, and thus R ¹ in the general formula (a) is the same group as R ^1A and R ^1B in the general formula (1) and R ^1C in the general formula (2). Like R ¹, R ²～R⁵ in the general formula (A) is the same group as the substituent corresponding to the general formulae (1) and (2). In the raw materials of the hole transporting agents (1) and (2), the compound (B) is common, and thus R ⁶ in the general formula (B) is the same group as R ^6A and R ^6B in the general formula (1) and R ^6C and R ^6D in the general formula (2). Like R ⁶, R ⁷～R¹⁰ in the general formula (B) is the same group as the substituent corresponding to the general formulae (1) and (2).

The palladium catalyst may be added to the solution subjected to the first stirring in the first stirring step and the solution subjected to the second stirring in the second stirring step. Examples of palladium catalysts are: palladium (II) acetate, palladium (II) chloride, sodium hexachloropalladium (IV) tetrahydrate and tris (dibenzylideneacetone) dipalladium (0).

The ligand may be added to the solution subjected to the first stirring in the first stirring step and the solution subjected to the second stirring in the second stirring step. Examples of the liquid include: 2-dicyclohexylphosphine-2 ',4',6' -triisopropylbiphenyl, (4-dimethylaminophenyl) di-tert-butylphosphine, tricyclohexylphosphine, triphenylphosphine and diphenylmethylphosphine.

The alkali may be added to the solution subjected to the first stirring in the first stirring step and the solution subjected to the second stirring in the second stirring step. Examples of the base include: sodium t-butoxide, tripotassium phosphate and cesium fluoride.

The solvent may be added to the solution subjected to the first stirring in the first stirring step and the solution subjected to the second stirring in the second stirring step. Examples of the solvent include: xylene, toluene, tetrahydrofuran and dimethylformamide.

The temperature of the solution subjected to the first stirring in the first stirring step and the solution subjected to the second stirring in the second stirring step is preferably 80 ℃ to 140 ℃. The time of the first stirring is preferably 1 hour to 10 hours, more preferably 5 hours to 10 hours. The second stirring time is preferably 1 hour to 10 hours, more preferably 1 hour to 4 hours. The first stirring and the second stirring may also be performed under an atmosphere of an inert gas (e.g., nitrogen or argon).

In the hole-transporting agent production step, the solution is not purified after the first stirring step. Therefore, the process for producing the hole-transporting agent can be simplified. The hole transporting agents (1) and (2) are obtained simultaneously in a mixed state through the first stirring step and the second stirring step. Since the mixture is obtained, the operation of separately metering and mixing the hole transporting agents (1) and (2) can be omitted when the coating liquid is prepared in the photosensitive layer forming step.

In the hole-transporting agent production step, the hole-transporting agent (2) remains in the hole-transporting agent obtained in the second stirring step. The hole-transporting agent (2) as a by-product is not completely removed, but instead the hole-transporting agent (2) is intentionally left, whereby the photosensitive layer can be made to contain both the hole-transporting agents (1) and (2). Therefore, the cracking resistance of the photoreceptor can be improved, and the crystallization of the photoreceptor can be suppressed. In addition, the second stirring step may be followed by purification so that the hole-transporting agent (2) is not completely removed. The second stirring step may be followed by purification so that the hole-transporting agent (1) is not completely removed. Examples of the purification method after the second stirring step include: activated clay treatment, recrystallization, and combinations thereof.

The content of the hole-transporting agent (2) relative to the total mass of the hole-transporting agents (1) and (2) can be adjusted, for example, by changing the ratio (B/a) of the amount of the additive of the compound (B) to the amount of the additive of the compound (a). The ratio (B/A) is a molar ratio conversion value. The higher the ratio (B/A), the higher the content of the hole-transporting agent (2) relative to the total mass of the hole-transporting agents (1) and (2). The ratio (B/A) is preferably 1.05 to 1.45, more preferably 1.05 to 1.25.

The content of the hole-transporting agent (2) relative to the total mass of the hole-transporting agents (1) and (2) can be adjusted, for example, by changing the ratio (a/C) of the amount of the additive of the compound (a) to the amount of the additive of the compound (C). The ratio (A/C) is a molar ratio conversion value. The higher the ratio (A/C), the higher the content of the hole-transporting agent (2) relative to the total mass of the hole-transporting agents (1) and (2). The ratio (A/C) is preferably 2.30 to 3.30, more preferably 2.30 to 2.60.

The content of the hole transporting agent (2) relative to the total mass of the hole transporting agents (1) and (2) can be adjusted, for example, by performing purification between the second stirring steps so that the hole transporting agent (2) is not completely removed and changing the purification conditions. In order to adjust the content of the hole-transporting agent (2) relative to the total mass of the hole-transporting agents (1) and (2), one or both of the hole-transporting agents (1) and (2) may be further added to the hole-transporting agent obtained through the first stirring step and the second stirring step.

(Photosensitive layer Forming Process)

In the photosensitive layer forming step, a coating liquid (specifically, a coating liquid for forming a photosensitive layer) is applied to the conductive substrate, and at least a part of a solvent contained in the coating liquid is removed, thereby forming a photosensitive layer. The coating liquid contains a charge generating agent, a hole transporting agent, an electron transporting agent, a binder resin, and a solvent.

The solvent contained in the coating liquid is not particularly limited as long as it can dissolve or disperse the components contained in the coating liquid. Examples of the solvent include: alcohols (more specifically, methanol, ethanol, isopropanol, butanol, etc.), aliphatic hydrocarbons (more specifically, n-hexane, octane, cyclohexane, etc.), aromatic hydrocarbons (more specifically, benzene, toluene, xylene, etc.), halogenated hydrocarbons (more specifically, methylene chloride, dichloroethane, carbon tetrachloride, chlorobenzene, etc.), ethers (more specifically, dimethyl ether, diethyl ether, tetrahydrofuran, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, etc.), ketones (more specifically, acetone, methyl ethyl ketone, cyclohexanone, etc.), esters (more specifically, ethyl acetate, methyl acetate, etc.), dimethyl formaldehyde, dimethyl formamide, and dimethyl sulfoxide. These solvents may be used singly or in combination of two or more.

The coating liquid is prepared by dissolving or dispersing a charge generating agent, a hole transporting agent, an electron transporting agent, and a binder resin in a solvent. In the dissolving or dispersing operation, for example, a bead mill, a roller mill, a ball mill, an attritor, a paint shaker or an ultrasonic disperser may be used.

Examples of the method for coating with the coating liquid include: dip coating, spray coating, spin coating and bar coating.

Examples of the method for removing at least a part of the solvent contained in the coating liquid include: heating, depressurizing and heating and depressurizing are combined. More specifically, a method of performing heat treatment (hot air drying) using a high-temperature dryer or a reduced-pressure dryer is exemplified. The temperature of the heat treatment is, for example, 40 ℃ to 150 ℃. The time of the heat treatment is, for example, 3 minutes to 120 minutes.

The method for producing a photoreceptor may further include a step of forming an intermediate layer and a protective layer, if necessary. The step of forming the intermediate layer and the protective layer can be appropriately selected from known methods.

< Image Forming apparatus >

Next, an image forming apparatus including the photoreceptor 1 according to the present embodiment will be described. Hereinafter, a tandem type color image forming apparatus will be described as an example with reference to fig. 4. Fig. 4 is a cross-sectional view of an example of an image forming apparatus.

The image forming apparatus 100 in fig. 4 includes image forming units 40a, 40b, 40c, and 40d, a transfer belt 50, and a fixing device 54. Hereinafter, the image forming units 40a, 40b, 40c, and 40d are each described as an image forming unit 40 without distinction.

The image forming unit 40 includes an image carrier 30, a charging device 42, an exposure device 44, a developing device 46, a transfer device 48, and a cleaning member 52. The image carrier 30 is the photoreceptor 1 of the present embodiment.

As described above, since the photoreceptor 1 of the present embodiment has excellent crack resistance, the durability of the image forming apparatus 100 can be improved by using such a photoreceptor 1 as the image carrier 30. As described above, since the photoreceptor 1 according to the present embodiment can suppress crystallization, the image forming apparatus 100 can form a high-quality image by using the photoreceptor 1 as the image carrier 30.

The image carrier 30 is provided at a central position of the image forming unit 40. The image carrier 30 is provided rotatably in the arrow direction (counterclockwise direction). Around the image carrier 30, a charging device 42, an exposure device 44, a developing device 46, a transfer device 48, and a cleaning member 52 are provided in this order from the upstream side in the rotation direction of the image carrier 30.

Toner images of several colors (for example, four colors of black, cyan, magenta, and yellow) are sequentially superimposed on the recording medium P on the transfer belt 50 by each of the image forming units 40a to 40 d.

The charging device 42 charges a surface (e.g., a peripheral surface) of the image carrier 30, for example, to a positive polarity. The charging device 42 is, for example, a charging roller.

The exposure device 44 exposes the surface of the charged image carrier 30. Thereby, an electrostatic latent image is formed on the surface of the image carrier 30. Based on the image data input into the image forming apparatus 100, an electrostatic latent image is formed.

The developing device 46 supplies toner to the surface of the image carrier 30, and develops the electrostatic latent image into a toner image. When the developing device 46 develops the electrostatic latent image into a toner image, the surface of the image carrier 30 is in contact with the surface (e.g., peripheral surface) of the developing device 46. That is, the image forming apparatus 100 adopts a contact development method. The developing device 46 is, for example, a developing roller. In the case where the developer is a one-component developer, the developing device 46 supplies toner as the one-component developer to the electrostatic latent image formed on the image carrier 30. In the case where the developer is a two-component developer, the developing device 46 supplies the toner contained in the two-component developer and the toner in the carrier to the electrostatic latent image formed on the image carrier 30. Thereby, the image carrier 30 carries the toner image.

The transfer belt 50 conveys the recording medium P between the image carrier 30 and the transfer portion 48. The transfer belt 50 is an endless belt. The transfer belt 50 is provided rotatably in the arrow direction (clockwise direction).

After the developing section 46 develops the toner image, the transfer section 48 transfers the toner image from the surface of the image carrier 30 to the transfer target. The transfer target is a recording medium P. Specifically, when the recording medium P contacts the surface of the image carrier 30, the transfer device 48 transfers the toner image from the surface of the image carrier 30 to the recording medium P. That is, the image forming apparatus 100 adopts a direct transfer method. The transfer device 48 is, for example, a transfer roller.

The cleaning member 52 is brought into contact with the surface of the image carrier 30, and the cleaning member 52 recovers the toner adhering to the peripheral surface of the image carrier 30. The cleaning member 52 is, for example, a cleaning blade.

After the toner image is transferred onto the recording medium P by the transfer device 48, the recording medium P is conveyed by the transfer belt 50 to the fixing device 54. The fixing device 54 is, for example, a heat roller and/or a pressure roller. The unfixed toner image transferred by the transfer device 48 is heated and/or pressurized by the fixing device 54. The toner image is heated and/or pressurized, whereby the toner image is fixed on the recording medium P. As a result, an image is formed on the recording medium P.

As described above, an example of the image forming apparatus is described, but the image forming apparatus is not limited to the image forming apparatus 100 described above. The image forming apparatus 100 described above is a color image forming apparatus, but the image forming apparatus may be a monochrome image forming apparatus. In this case, the image forming apparatus may include, for example, only 1 image forming unit. Although the image forming apparatus 100 described above adopts the tandem system, the image forming apparatus may adopt a swing system (rotation system), for example. The charging device 42 is described as a charging roller, but the charging device may be a charging device other than a charging roller (for example, a scorotron charger, a charging brush, or a corotron charger). The image forming apparatus 100 described above adopts the contact development method, but the image forming apparatus may adopt the noncontact development method. The image forming apparatus 100 described above adopts the direct transfer method, but the image forming apparatus may adopt the intermediate transfer method. In the case where the image forming apparatus adopts the intermediate transfer system, the intermediate transfer belt corresponds to the transferred body. The cleaning member 52 is described as a cleaning blade, but the cleaning member may be a cleaning roller. The image forming unit 40 described above does not include a static electricity eliminating device, but the image forming unit may include a static electricity eliminating device.

[ Example ]

Hereinafter, the present invention will be described more specifically by using examples. The invention is not in any way limited to the scope of the embodiments.

The following charge generating agent, electron transporting agent, hole transporting agent, and binder resin were prepared as materials for forming the photosensitive layer of the photoreceptor.

(Charge generating agent)

The Y-type oxytitanium phthalocyanine described in the embodiment was prepared as a charge generating agent.

(Electron transporting agent)

Each of the electron-transporting agents (E-1), (E-2) and (E-3) described in the embodiments was prepared as an electron-transporting agent. The compound represented by the formula (E-4) (hereinafter, referred to as an electron mediator (E-4)) was prepared as an electron mediator used in the comparative example.

[ Chemical formula 22]

(Adhesive resin)

Each of the polyarylate resin (R-1) and the polycarbonate resin (R-2) described in the embodiment was prepared as a binder resin. The viscosity average molecular weight of the polyarylate resin (R-1) was 47,500. The viscosity average molecular weight of the polycarbonate resin (R-2) was 50,000.

(Hole transporting agent)

Samples (M-A1) to (M-A4) as a mixture of the hole transporting agents (1) and (2) were synthesized by the following methods. The samples (M-B1) to (M-B5) used in the comparative examples were synthesized by the following methods. The components of the samples (M-A1) to (M-A4) and (M-B1) to (M-B5) are shown in Table 3. The technical terms in table 3 are as follows. The "HTM (1)" and "HTM (2)" in the "kind" column represent the kind of the hole transporting agent (1) and the kind of the hole transporting agent (2), respectively. "HTM (1)" in the "content" column indicates: the content (unit: mass%) of the hole transporting agent (1) relative to the total mass of the hole transporting agent (1) and the hole transporting agent (2). "HTM (2)" in the "content" column indicates: the content (unit: mass%) of the hole transporting agent (2) relative to the total mass of the hole transporting agent (1) and the hole transporting agent (2). "-" indicates that the sample does not contain the hole transporting agent.

[ Table 3]

In the following description of the synthetic methods of the respective samples, the compounds represented by the following chemical formulas (A-1) to (A-4), (B-1) to (B-2) and (C-1) are sometimes referred to as compounds (A-1) to (A-4), (B-1) to (B-2) and (C-1), respectively.

[ Chemical formula 23]

(Preparation of sample (M-A1))

The preparation of the sample (M-A1) was carried out according to the following reaction equation (r-a).

[ Chemical 24]

Specifically, in a 500mL three-necked flask equipped with a separate chute, tris (dibenzylideneacetone) dipalladium (0.0366 g, 0.040 mmol), 2-dicyclohexylphosphine-2 ',4',6' -triisopropylbiphenyl (0.0763 g, 0.016 mmol) and sodium t-butoxide (9.669 g, 100.7 mmol) were placed. The degassing and nitrogen substitution in the flask were repeated 2 times, and the air in the flask was substituted with nitrogen.

Then, 2-ethylaniline (compound (A-1), 8.45g, 69.8 mmol), 4-chlorotoluene (compound (B-1), 10.13g, 80.0 mmol) and xylene (45 g) were further charged into the flask. The solution in the flask was heated to 130 ℃ and refluxed. In addition, the temperature of the solution was raised while evaporating t-butanol generated during the temperature raising. The solution was kept at 130 ℃ and stirred for 2 hours (corresponding to the first stirring) while the solution was refluxed. The solution in the flask was then cooled to 50 ℃.

Then, sodium t-butoxide (7.680 g, 80.0 mmol), 4 "-dibromo-p-terphenyl (compound (C-1), 11.60g, 30.0 mmol), palladium (II) acetate (0.0168 g, 0.075 mmol), 2-dicyclohexylphosphine-2 ',4',6' -triisopropylbiphenyl (0.1425 g, 0.299 mmol), and xylene (32 g) were further added to the solution in the flask. The solution in the flask was heated to 130 ℃ and refluxed. In addition, the temperature of the solution was raised while evaporating t-butanol generated during the temperature raising. The solution was maintained at 130 ℃ and stirred for 3 hours (corresponding to the second stirring) while the solution was refluxed.

The solution in the flask was then cooled to 90 ℃. The solution at 90℃in the flask was filtered to remove insoluble matter in the solution, and a filtrate was obtained. The filtrate was subjected to 2 times of activated clay treatment. The activated clay treatment is a treatment in which activated clay (SA-1, 8g, manufactured by Japanese activated clay Co., ltd.) is put into the filtrate and the filtrate is recovered by filtration again at 110℃for 15 minutes. The filtrate subjected to the 2-time activated clay treatment was concentrated under reduced pressure to obtain a concentrated solution. To the concentrate, isohexane was added in an amount (about 50 g) that made the concentrate slightly cloudy, followed by methanol (50 g). The concentrate was cooled to 5℃and precipitated crystals were removed by filtration. The crystals were placed in xylene (100 g) and heated to 110℃to dissolve the crystals in xylene to give a solution. The solution was subjected to the above-mentioned activated clay treatment 5 times. The filtrate subjected to the activated clay treatment 5 times was concentrated under reduced pressure to obtain a concentrated solution. To the concentrate, isohexane was added in an amount (about 50 g) that made the concentrate slightly cloudy, followed by methanol (50 g). The concentrate was cooled to 5℃and precipitated crystals were removed by filtration. The resulting crystals were dried at 70℃under vacuum for 24 hours to give a sample (M-A1). thesample(M-A1)isamixturecontainingaholetransportingagent(HTM-1)andaholetransportingagent(HTM-A). The yield of the sample (M-A1) was 16.3g. The yield of the hole transporter (HTM-1) contained in the sample (M-A1) was 84% relative to the compound (C-1).

(Preparation of sample (M-A2))

Sample (M-A2) was obtained in the same manner as in the preparation of sample (M-A1), except that 69.8mmol of compound (A-1) was changed to 69.8mmol of compound (A-2). The sample (M-A2) is a mixture containing a hole transporting agent (HTM-2) and a hole transporting agent (HTM-B).

(Preparation of sample (M-A3))

Sample (M-A3) was obtained in the same manner as in the preparation of sample (M-A1), except that 69.8mmol of compound (A-1) was changed to 69.8mmol of compound (A-3). The sample (M-A3) is a mixture containing a hole transporting agent (HTM-3) and a hole transporting agent (HTM-C).

(Preparation of sample (M-A4))

A sample (M-A4) was obtained in the same manner as in the preparation of sample (M-A1), except that 69.8mmol of compound (A-1) was changed to 69.8mmol of compound (A-4), and 80.0mmol of compound (B-1) was changed to 80.0mmol of compound (B-2). The sample (M-A4) is a mixture containing a hole transporting agent (HTM-4) and a hole transporting agent (HTM-D).

(Preparation of sample (M-B1))

The sample (M-A1) was purified by silica gel column chromatography using a mixed solvent of toluene and isohexane (volume ratio 50/50) as a developing agent. Thus, a component containing the hole transporter (HTM-1) was separated. The solution (component) was concentrated under reduced pressure until the separated solution was slightly cloudy, thereby obtaining a concentrated solution. Isohexane and methanol were added to the concentrate. The concentrated solution was cooled to 5℃and precipitated crystals were removed by filtration to obtain a sample (M-B1). thesample(M-B1)containedonlythehole-transportingagent(HTM-1),andnohole-transportingagent(HTM-A).

(Preparation of sample (M-B2))

Sample (M-B2) was obtained in the same manner as in the preparation method of sample (M-B1), except that sample (M-A1) was changed to sample (M-A2). Sample (M-B2) contained only the hole transporter (HTM-2), and no hole transporter (HTM-B).

(Preparation of sample (M-B3))

Sample (M-B3) was obtained in the same manner as in the preparation method of sample (M-B1), except that sample (M-A1) was changed to sample (M-A3). Sample (M-B3) contained only the hole-transporting agent (HTM-3), and no hole-transporting agent (HTM-C).

(Preparation of sample (M-B4))

Sample (M-B4) was obtained in the same manner as in the preparation method of sample (M-B1), except that sample (M-A1) was changed to sample (M-A4). Sample (M-B4) contained only the hole-transporting agent (HTM-4), and no hole-transporting agent (HTM-D).

(Preparation of sample (M-B5))

The sample (M-A1) was purified by silica gel column chromatography using a mixed solvent of toluene and isohexane (volume ratio 50/50) as a developing agent. thus,acomponentcontainingtheholetransporter(HTM-A)wasseparated. The solution (component) was concentrated under reduced pressure until the separated solution was slightly cloudy, thereby obtaining a concentrated solution. Isohexane and methanol were added to the concentrate. The concentrated solution was cooled to 5℃and precipitated crystals were removed by filtration to give a sample (M-B5). thesample(M-B5)containedonlythehole-transportingagent(HTM-A),andnohole-transportingagent(HTM-1).

(Measurement of the content of the hole-transporting agent (1) and the hole-transporting agent (2))

Regarding each sample prepared, the content of the hole-transporting agent (1) was measured with respect to the total mass of the hole-transporting agent (1) and the hole-transporting agent (2). The content of the hole-transporting agent (1) is the content of the hole-transporting agents (HTM-1) to (HTM-4) contained in the general formula (1). The content of the hole-transporting agent (2) was measured for each sample prepared, relative to the total mass of the hole-transporting agent (1) and the hole-transporting agent (2). thecontentofthehole-transportingagent(2)isthecontentofthehole-transportingagents(HTM-A)to(HTM-D)containedinthegeneralformula(2). The measurement method is as follows.

The obtained tetrahydrofuran solution was analyzed by High Performance Liquid Chromatography (HPLC), specifically, the tetrahydrofuran solution as a sample was analyzed by the following analysis device and analysis conditions to obtain an HPLC chart, the content of the hole transporter (1) in the HPLC chart was determined from the peak area of the hole transporter (1) in the HPLC chart, the content of the hole transporter (2) in the HPLC chart was determined from the peak area of the hole transporter (2) in the HPLC chart, and the content of the hole transporter (1) and the content of the hole transporter (2) were calculated from the content of the hole transporter (1) and the content of the hole transporter (2) determined.

(Analysis device and analysis conditions)

Analysis device: HITACHI HIGH-Technologies Corporation manufactured "LaChrom ELITE"

Detection wavelength: 254nm

Chromatographic column: GL SCIENCES Inc. manufactured "Inertsil (Japanese registered trademark) ODS-3" (inner diameter: 4.6mm; length: 250 mm)

Column temperature: 40 DEG C

Developing agent: acetonitrile

Flow rate: 1 mL/min

Sample injection amount: 1 mu L

< Production of photoreceptor >

The above-prepared charge generating agents, electron transporting agents, hole transporting agents and binder resins were used to produce photoreceptors (PA-1) to (PA-9) and (PB-1) to (PB-10).

(Production of photoreceptor (PA-1))

Usingaballmill,3partsbymassofY-typeoxytitaniumphthalocyanineasachargegeneratingagent,70partsbymassofasample(M-A1)(specifically,amixtureof67partsbymassofaholetransportingagent(HTM-1)and3partsbymassofaholetransportingagent(HTM-a)),100partsbymassofapolyarylateresin(r-1)asabinderresin,30partsbymassofanelectrontransportingagent(e-1)and800partsbymassoftetrahydrofuranasasolventweremixedfor50hourstoobtainacoatingliquid. The coating liquid was applied to the conductive substrate (aluminum drum support) by dip coating. The coated coating liquid was dried at 120℃with hot air for 60 minutes. Thus, a photosensitive layer (film thickness: 28 μm) was formed on the conductive substrate, and a photoreceptor (PA-1) was obtained. In the photoreceptor (PA-1), a single photosensitive layer is directly formed on a conductive substrate.

(Production of photoreceptors (PA-2) to (PA-9) and (PB-1) to (PB-10))

The photoreceptors (PA-2) to (PA-9) and (PB-1) to (PB-10) were produced according to the production method of the photoreceptor (PA-1), except that the samples of the types shown in Table 4, the electron mediator and the binder resin were used.

< Evaluation >

For each of the photoreceptors (PA-1) to (PA-9) and (PB-1) to (PB-10) to be evaluated, the sensitivity characteristics, the cracking resistance, and whether crystallization was suppressed were evaluated as follows.

< Evaluation of sensitivity Properties >

The photosensitive characteristics of the photoreceptor were evaluated in an environment of a temperature of 23℃and a relative humidity of 50% RH. The surface of the photoreceptor was charged to +750v using a drum sensitivity tester (GENTEC, inc.). Then, monochromatic light (wavelength: 780nm; exposure amount: 0.7. Mu.J/cm ²) was extracted from the light of the halogen lamp using a band-pass filter, and irradiated onto the surface of the photoreceptor. After the end of the irradiation of the monochromatic light, the surface potential of the photoreceptor was measured at a time of 40 milliseconds. The measured surface potential was taken as the post-exposure potential V _L (unit: +V) of the photoreceptor. The post-exposure potential V _L of the photoreceptor is shown in table 4. The photoreceptor having the post-exposure potential V _L of +150v or less was evaluated as having good sensitivity characteristics.

< Evaluation of crack resistance >

The evaluation environment for the cracking resistance of the photoreceptor was an environment with a temperature of 23℃and a relative humidity of 50% RH. The lower 40mm region of the photoreceptor was immersed in an isoparaffinic solvent (Isopar L, manufactured by ExxonMobil corporation) for 24 hours. After 24 hours of immersion, the number of cracks generated on the surface of the photoreceptor was confirmed. The crack resistance was evaluated based on the number of cracks according to the following criteria. The evaluation results are shown in table 4.

Evaluation a (particularly good): the number of cracks was 20 or less.

Evaluation B (good): the number of cracks is 21 to 100.

Evaluation C (bad): the number of cracks is 101 or more.

< Evaluation of crystallization inhibition >

The entire photosensitive layer of the photoreceptor was visually observed to confirm whether or not a crystallized portion was present on the photosensitive layer. Based on the results of the confirmation, it was evaluated whether or not the crystallization of the photoreceptor was suppressed, according to the following criteria. The evaluation results are shown in table 4.

Evaluation a (good): no occurrence of crystallized portions was confirmed.

Evaluation B (bad): it was confirmed that crystallization occurred.

The technical terms in table 4 mean as follows. "HTM" means a hole transporter. "HTM (1)" means the hole transporter (1). "HTM (2)" means the hole transporter (2). "ETM" means an electron transport agent. "resin" means a binder resin. "V _L" represents the post-exposure potential. "crack" indicates the evaluation result of the cracking resistance of the photoreceptor. "crystallization" means an evaluation result of whether or not crystallization of the photoreceptor is suppressed. "-" means that the component is absent.

[ Table 4]

As shown in table 4, the photosensitive layers of the photoreceptors (PA-1) to (PA-9) are single-layered, and contain a charge generating agent, a hole transporting agent, an electron transporting agent, and a binder resin. inthephotosensitivelayer,theholetransportingagentcontainstwokindsofholetransportingagents(1)and(2)(morespecifically,holetransportingagents(HTM-1)and(HTM-a),holetransportingagents(HTM-2)and(HTM-b),holetransportingagents(HTM-3)and(HTM-c),orholetransportingagents(HTM-4)and(HTM-d)). In the photosensitive layer, the electron transporting agent contains an electron transporting agent (10), (11) or (12) (more specifically, an electron transporting agent (E-1), (E-2) or (E-3)). The evaluation of the cracking resistance of the photoreceptors (PA-1) to (PA-9) was A or B, and the cracking resistance of these photoreceptors was excellent. The evaluation of the inhibition of crystallization of the photoreceptors (PA-1) to (PA-9) was A, and crystallization of these photoreceptors was inhibited. The post-exposure potential V _L of the photoreceptors (PA-1) to (PA-9) is +150V or less, and these photoreceptors achieve improvement of cracking resistance and suppression of crystallization without impairing the sensitivity characteristics.

As described above, the photoreceptor according to the present invention exhibits excellent crack resistance and can suppress crystallization. Further, since the photoreceptor according to the present invention is excellent in cracking resistance and can suppress crystallization, it can be judged that the image forming apparatus including the photoreceptor is excellent in durability and can form a good-quality image. Further, according to the method for producing a photoreceptor of the present invention, it is possible to produce a photoreceptor excellent in crack resistance and capable of suppressing crystallization while simplifying the hole-transporting agent production process.

Claims

1. An electrophotographic photoreceptor which comprises a substrate and a photosensitive layer,

Comprises a conductive substrate and a photosensitive layer,

The photosensitive layer is a single layer and,

The photosensitive layer contains a charge generating agent, a hole transporting agent, an electron transporting agent and a binder resin,

The hole transporting agent contains a first hole transporting agent which is a compound represented by the general formula (1) and a second hole transporting agent which is a compound represented by the general formula (2),

The electron transport agent contains a compound represented by the formula (E-1),

The binder resin contains a polyarylate resin containing repeating units represented by the chemical formulas (10-2), (11-X1) and (11-X3),

In the general formula (1), R ^1A、R^2A、R^3A、R^4A、R^5A、R^6A、R^7A、R^8A、R^9A and R ^10A each independently represent a hydrogen atom, a C1-C8 alkyl group, a C1-C8 alkoxy group or a C6-C14 aryl group,

R ^1B in the general formula (1) and R ^1C in the general formula (2) are the same groups as R ^1A in the general formula (1),

R ^2B in the general formula (1) and R ^2C in the general formula (2) are the same groups as R ^2A in the general formula (1),

R ^3B in the general formula (1) and R ^3C in the general formula (2) are the same groups as R ^3A in the general formula (1),

R ^4B in the general formula (1) and R ^4C in the general formula (2) are the same groups as R ^4A in the general formula (1),

R ^5B in the general formula (1) and R ^5C in the general formula (2) are the same groups as R ^5A in the general formula (1),

R ^6B in the general formula (1) and R ^6C and R ^6D in the general formula (2) are the same groups as R ^6A in the general formula (1),

R ^7B in the general formula (1) and R ^7C and R ^7D in the general formula (2) are the same groups as R ^7A in the general formula (1),

R ^8B in the general formula (1) and R ^8C and R ^8D in the general formula (2) are the same groups as R ^8A in the general formula (1),

R ^9B in the general formula (1) and R ^9C and R ^9D in the general formula (2) are the same groups as R ^9A in the general formula (1),

R ^10B in the general formula (1) and R ^10C and R ^10D in the general formula (2) are the same groups as R ^10A in the general formula (1),

Y in the general formula (1) is a divalent group represented by the chemical formula (Y2),

2. The electrophotographic photoreceptor as claimed in claim 1, wherein,

Thecompoundrepresentedbythegeneralformula(1)isacompoundrepresentedbythechemicalformula(HTM-1),andthecompoundrepresentedbythegeneralformula(2)isacompoundrepresentedbythechemicalformula(HTM-A),

Or the compound represented by the general formula (1) is a compound represented by the formula (HTM-2), and the compound represented by the general formula (2) is a compound represented by the formula (HTM-B),

Or the compound represented by the general formula (1) is a compound represented by the formula (HTM-3), and the compound represented by the general formula (2) is a compound represented by the formula (HTM-C),

Or the compound represented by the general formula (1) is a compound represented by the formula (HTM-4), and the compound represented by the general formula (2) is a compound represented by the formula (HTM-D),

3. The electrophotographic photoreceptor as claimed in claim 1 or 2, wherein,

The photosensitive layer is an outermost surface layer.

4. An image forming apparatus includes:

An image bearing body;

a charging device that charges a surface of the image carrier to a positive polarity;

an exposure device that exposes the surface of the charged image carrier and forms an electrostatic latent image on the surface of the image carrier;

A developing device that develops the electrostatic latent image into a toner image; and

A transfer device that transfers the toner image from the image bearing member to a transfer target, the image bearing member being the electrophotographic photoreceptor according to any one of claims 1 to 3.

5. The image forming apparatus according to claim 4, wherein,

The transfer target is a recording medium and,

The transfer device transfers the toner image from the image bearing member onto the recording medium while the recording medium contacts the surface of the image bearing member.

6. The image forming apparatus according to claim 4, wherein,

The surface of the image carrier is in contact with the developing device.

7. A method of manufacturing a semiconductor device, which comprises,

The electrophotographic photoreceptor according to any of claims 1 to 3,

The manufacturing method comprises a hole transporter manufacturing process and a photosensitive layer forming process,

In the hole-transporting agent production step, the hole-transporting agent is produced,

In the photosensitive layer forming step, a coating liquid containing the charge generating agent, the hole transporting agent, the electron transporting agent, the binder resin, and a solvent is applied to the conductive substrate, and at least a part of the solvent contained in the coating liquid is removed to form the photosensitive layer,

The hole-transporting agent production process includes a first stirring process and a second stirring process,

In the first stirring step, a mixed solution containing a compound represented by the general formula (A) and a compound represented by the general formula (B) is subjected to first stirring,

In the second stirring step, a compound represented by the general formula (C) is further added into the mixed solution, and the mixed solution is subjected to second stirring,

After the first stirring step, the second stirring step is performed without purifying the mixed solution,

After the first stirring step and the second stirring step, the hole transporting agent containing the first hole transporting agent and the second hole transporting agent is obtained,

R ¹、R²、R³、R⁴ and R ⁵ in the general formula (A) are the same groups as R ^1A、R^2A、R^3A、R^4A and R ^5A in the general formula (1), respectively,

R ⁶、R⁷、R⁸、R⁹ and R ¹⁰ in the general formula (B) are the same groups as R ^6A、R^7A、R^8A、R^9A and R ^10A in the general formula (1), respectively, Z ¹ in the general formula (B) represents a halogen atom,

Y in the general formula (C) is the same group as Y in the general formula (1), and Z ² and Z ³ in the general formula (C) represent halogen atoms.