JP3269981B2 - Electrophotographic photoreceptor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic photosensitive member used for an image forming apparatus such as an electrostatic copying machine, a facsimile, and a laser beam printer.

[0002]

2. Description of the Related Art In recent years, various photoconductors having sensitivity in a wavelength region of a light source used in the image forming apparatus have been used. One is an inorganic photoreceptor using an inorganic material such as selenium for the photosensitive layer, and the other is an organic photoreceptor (OPC) using an organic material for the photosensitive layer. Organic photoreceptors are easier to manufacture than inorganic photoreceptors, and have a wide variety of photoreceptor materials, such as charge transport agents, charge generators, and binder resins, and a high degree of freedom in functional design. Extensive research is ongoing.

[0003] The organic photoreceptor includes a laminated photoreceptor in which a charge generating layer containing a charge generating agent and a charge transporting layer containing a charge transporting agent are laminated, and a single charge generating agent and a charge transporting agent. There is a single-layer type photoreceptor dispersed in a photosensitive layer. Of these, photoconductors that are practically used are generally of a laminated type,
From the viewpoint of mechanical strength, a stacked photoreceptor in which a charge transport layer having a thickness greater than that of the charge generation layer is arranged as the outermost layer is more common.

[0004] Charge transporting agents used in these photoreceptors are required to have high carrier mobility, but most of the charge transporting agents having high carrier mobility have hole transporting properties. For this reason, the laminated photoreceptor in which the charge transport layer is disposed as the outermost layer is of a negative charge type. However, the negatively charged organic photoreceptor needs to be charged by a negative corona discharge, which generates a large amount of ozone, and the ozone affects the environment and deteriorates the photoreceptor itself.

[0005] In order to solve the above problems, use of an electron transporting agent as a charge transporting agent has been studied. For example, JP-A-1-206349 proposes using a compound having a diphenoquinone structure or a benzoquinone structure as an electron transporting agent, and JP-A-6-110227 discloses a compound represented by the general formula (ET13):

[0006]

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^Wherein R ^e22 represents a halogen atom, an alkyl group which may have a substituent, a phenyl group which may have a substituent, an alkoxycarbonyl group, an N-alkylcarbamoyl group, a cyano group or Represents a nitro group, μ represents an integer of 0 to 3. When μ is 2 or more, each R
^e22 may be different from each other. It has been proposed to use a naphthoquinone derivative represented by the formula (1) as an electron transport agent.

[0008]

However, conventional electron transporting agents such as the compound having a diphenoquinone structure or a benzoquinone structure and the naphthoquinone derivative represented by the general formula (ET13) generally have a matching with a charge generating agent. It is difficult, and the electron injection from the charge generating agent to the electron transporting agent is insufficient. Further, such an electron transporting agent has poor compatibility with the binder resin and is not uniformly dispersed in the photosensitive layer.
The hopping distance of the electrons becomes longer, and the electron transfer is less likely to occur particularly in a low electric field.

Therefore, the photoreceptor containing the conventional electron transporting agent has a problem that the residual potential becomes high and the sensitivity becomes insufficient, as is clear from the electrical property test described in Examples described later. . Further, the single-layer type photoreceptor has an advantage that one photoreceptor can be used for both the positively charged type and the negatively charged type by using an electron transporting agent and a hole transporting agent in combination, but the diphenoquinone derivative described above is used. When a naphthoquinone derivative (ET13) is used as an electron transporting agent, a problem arises in that a charge transfer complex is formed by interaction with a hole transporting agent, and the transport of electrons and holes is inhibited.

Accordingly, an object of the present invention is to solve the above-mentioned technical problems and to provide an electrophotographic photoreceptor having improved sensitivity as compared with the prior art.

[0011]

Means for Solving the Problems The inventors of the present invention have made intensive studies to solve the above-mentioned problems, and as a result, the present invention relates to an electrophotographic photosensitive member having a photosensitive layer provided on a conductive substrate. Has the general formula (1):

[0012]

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(Wherein R ¹ is an alkyl group, an aryl group,
Aralkyl groups, acyl Motoma other represents a cyano group. When the phthaloylpyrrolocholine derivative represented by the formula (1) is contained, the present inventors have found a new fact that the residual potential is lower and the sensitivity is higher than that of a conventional electrophotographic photoreceptor containing an electron transporting agent. I came to.

The phthaloylpyrrolocholine derivative represented by the general formula (1) has a naphthoquinone structure, and has excellent electron acceptability due to the action of a pyrrolocholine ring (indolizine ring) fused to a naphthoquinone ring. It has good compatibility with the binder resin and is uniformly dispersed in the photosensitive layer. Further, it is excellent in matching with the charge generating agent, and the injection of electrons from the charge generating agent is performed smoothly.

Therefore, the photosensitive layer containing the phthaloylpyrrolocholine derivative (1) is excellent in the electron transporting property under a low electric field, and has a low rate of recombination of electrons and holes in the photosensitive layer. As a result, the apparent charge generation efficiency approaches the actual value, so that the sensitivity of the photoreceptor having such a photosensitive layer is improved. Further, the residual potential of the photoreceptor is reduced, and the stability and durability when repeatedly exposed are improved.

In particular, since the phthaloylpyrrolocholine derivative (1) does not form a charge transfer complex with a hole transporting agent, a single-layer type containing an electron transporting agent and a hole transporting agent in the same photosensitive layer. When the photoreceptor is used, a highly sensitive photoreceptor can be obtained. Further, the photosensitive layer has a general formula
(1 '):

Embedded image (Wherein R ^{1 ′} is an alkyl group, an aryl group, an aralkyl
Group, acyl group, alkoxycarbonyl group, aryloxy
A cyclocarbonyl group, an aralkyloxycarbonyl group or
Shows a cyano group. ) Phthalonitrile represented by yl pyrrolo choline <br/> induction body (electron transferring material), as another electron transferring material, electron transferring material redox potential is -0.8 to-1.4V
, The sensitivity of the photoreceptor is further improved.

This is because the other electron transporting agent extracts electrons from the charge generating agent, and the one electron transporting agent is the main electron transporting agent.
'By reaching transfer <br/> the phthaloyl pyrrolo choline induced body represented by phthaloyl pyrrolo choline derivative from the electric charge generating material (1 general formula (1)') electron injection for becomes smoother to It is presumed. The other electron transporting agent is preferably represented by the following general formula (2), particularly in consideration of a combination with the phthaloylpyrrolocholine derivative (1 ′) as a main electron transporting agent.

[0018]

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(Wherein R ^A , R ^B , R ^C and R ^D are the same or different and each have a hydrogen atom, an alkyl group, an aryl group, an aralkyl group, a cycloalkyl group, an alkoxy group or a substituent. A diphenoquinone derivative represented by the general formula (3):

[0020]

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(Wherein R ^E , R ^F , R ^G and R ^H are the same or different and each have a hydrogen atom, an alkyl group, an aryl group, an aralkyl group, a cycloalkyl group, an alkoxy group or a substituent. A benzoquinone derivative represented by the following formula:

[0022]

BEST MODE FOR CARRYING OUT THE INVENTION The above general formula (1) and general formula (1 ′)
In the phthaloylpyrrolocholine derivative represented by the formula, among the groups corresponding to the groups R ¹ and R ^{1 ′} , examples of the alkyl group include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, and s- Examples thereof include groups having 1 to 6 carbon atoms such as butyl, t-butyl, n-pentyl and n-hexyl. Examples of the aryl group include groups such as phenyl, tolyl, xylyl, naphthyl, anthryl, phenanthryl, fluorenyl, biphenylyl, o-terphenyl and the like. Examples of the aralkyl group include groups such as benzyl, benzhydryl, trityl, and phenethyl. The aryl group and the aralkyl group may be further substituted with an alkyl group or the like, and the number and position of substitution of these groups are not particularly limited. Examples of the acyl group include alkanoyl groups having 1 to 6 carbon atoms such as acetyl, propionyl, butyryl, isobutyryl, valeryl, isovaleryl, pivaloyl, and hexanoyl, and groups such as benzoyl, naphthoyl, toluoyl, and benzylcarbonyl. Examples of the alkoxycarbonyl group include groups such as methoxycarbonyl. Examples of the aryloxycarbonyl group include groups such as phenoxycarbonyl. Examples of the aralkyloxycarbonyl group include groups such as benzyloxycarbonyl. The alkoxy moiety in the alkoxycarbonyl group includes, for example, an alkoxy group having 1 to 6 carbon atoms such as methoxy, ethoxy, n-propoxy, isopropoxy, t-butoxy, n-pentyloxy and n-hexyloxy. Is raised. The aryl moiety in the aryloxycarbonyl group includes groups similar to the above-described aryl groups. The aralkyl moiety in the aralkyloxy group exemplified above includes the same groups as the aralkyl groups exemplified above.

Specific examples of the phthaloylpyrrolocholine derivatives represented by the general formulas (1) and (1 ′) include, for example, the following formulas (1′-1), (1-2) to (1-2) 7), (1'-8), (1'-9)
And the compound represented by

[0024]

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[0025]

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The phthaloylpyrrolocholine derivative represented by the general formula (1) and the general formula (1 ′) is, for example, represented by the following reaction formula
As shown in (I), Ernest Efplat et al.
estF. Pratt, et al.) for the Journal of American Chemical Society (J. Am. Chem. So
c.), 79, 1212 (1957). Reaction formula (I)

[0027]

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That is, a phthaloylpyrrolocholine derivative
(1) and (1 ′) are obtained by adding 2,3-dichloro-1,4-naphthoquinone (4) and a ketone compound (5) to pyridine and alcohol in the presence of a base or the like, It is obtained by heating and refluxing for about an hour. The electrophotographic photoreceptor of the present invention has a photosensitive layer containing a phthaloylpyrrolocholine derivative represented by the general formula (1) and the general formula (1 ′) as an electron transporting agent provided on a conductive substrate. It is.

The electrophotographic photoreceptor of the present invention can be applied to both a single-layer type and a multilayer type. appear. The single-layer photoreceptor has a single photosensitive layer containing at least a phthaloylpyrrolocholine derivative (1) as an electron transporting agent, a charge generating agent, and a binder resin on a conductive substrate. is there. Such a single-layer type photosensitive layer can cope with either positive or negative charging by a single structure, but is preferably used in a positive charging type which does not require the use of a negative corona discharge. This single-layer type photoreceptor has the advantages that the layer configuration is simple and excellent in productivity, that the occurrence of film defects in the photosensitive layer can be suppressed, and that the optical characteristics can be improved because the number of interfaces between the layers is small. Have.

A single-layer type photoreceptor using the above phthaloylpyrrolocholine derivative (1), which is an electron transporting agent, in combination with a hole transporting agent having an excellent hole transporting property is, as described above, a phthaloylpyrrolocholine. Since there is no interaction between the derivative (1) and the hole transport agent, electron transport and hole transport can be performed efficiently even when both transport agents are contained in the same photosensitive layer at a high concentration. And a highly sensitive photoreceptor can be obtained.

On the other hand, the laminated type photoreceptor is formed on a conductive substrate.
A charge generating layer containing a charge generating agent and a charge transporting layer containing a charge transporting agent are laminated in this order or in the reverse order. However, since the charge generation layer is very thin compared to the charge transport layer, it is preferable to form the charge generation layer on a conductive substrate and to form the charge transport layer thereon for protection. .

The positive / negative charging type is selected according to the order of forming the charge generating layer and the charge transporting layer and the type of the charge transporting agent used in the charge transporting layer. . For example, in a layer configuration in which a charge generating layer is formed on a conductive substrate and a charge transporting layer is formed thereon, an electron transporting agent such as the phthaloylpyrrolocholine derivative (1) is used as a charge transporting agent in the charge transporting layer. When using the agent,
It becomes a positive charging type photoconductor. In this case, the charge generation layer may contain a hole transporting agent. When a hole transporting agent is used as the charge transporting agent in the charge transporting layer in the above-described layer configuration, a negatively charged photoreceptor is obtained. In this case, the charge generation layer may contain an electron transport agent.

In the photoreceptor of the present invention, the general formula
The oxidation-reduction potential is -0.8 to -1.4 V together with the phthaloylpyrrolocholine derivative (electron transporting agent) represented by (1 ').
The Rukoto other electron transferring material is not contained in the photosensitive layer
Therefore, the effect that the residual potential is greatly reduced and the sensitivity of the photoconductor is further improved can be obtained.

Another electron transporting agent having an oxidation-reduction potential within the above range is LUMO (Lowest Unoccupied Molecular).
Orbital (lowest unoccupied orbital) has a lower energy compliance than that of the charge generating agent. Therefore, when an ion pair of electrons (-) and holes (+) is generated in the charge generating agent by light irradiation, Extract electrons efficiently (ie, act as an electron acceptor). For this reason, the rate of disappearance of ion pairs due to recombination of electrons and holes is reduced, and charge generation efficiency is improved. The other electron transporting agent also functions to efficiently transfer electrons extracted from the charge generating agent to the phthaloylpyrrolocholine derivative (1 ′) , which is the main electron transporting agent. Therefore, in the combined use system of the phthaloylpyrrolocholine derivative (1 ′) and the other electron transporting agent, the injection and transport of electrons from the charge generating agent are performed smoothly, and the sensitivity of the photoreceptor is further improved.

The redox potential of the other electron transporting agent is -0.8
When it is larger than V, there is a possibility that the electron which moves while repeating the trap-detrap is reduced to a level at which detrap cannot be performed, thereby causing a carrier trap. Since this carrier trap hinders electron transport, it causes a reduction in the sensitivity of the photoconductor. Conversely, when the redox potential of the other electron transporting agent is smaller than -1.4 V, the energy level of LUMO becomes higher than that of the charge generating agent, and electrons are transferred to the other electron transporting agent when the ion pair is generated. As a result, there is a possibility that the charge generation efficiency may not be improved. The oxidation-reduction potential of the other electron transporting agent is preferably -0.85 to -1.00 V even within the above range, in consideration of the sensitivity of the photoreceptor.

As shown in FIG. 1, the oxidation-reduction potential can be calculated from the relationship between the traction voltage (V) and the current (μA) by E ₁ shown in FIG.
The and E ₂ was determined and calculated using the following equation. Oxidation-reduction potential (V) = (E ₁ + E ₂ ) / 2 The above pulling voltage (V) and current (μA) are measured by a three-electrode cyclic voltametry using a measurement solution prepared by mixing the following materials. did.

Electrodes: working electrode (glassy carbon electrode), counter electrode (platinum electrode) Reference electrode: silver nitrate electrode (0.1 mol / l AgNO ₃ -acetonitrile solution) Measurement solution Electrolyte: tetra-n-butylammonium perchlorate 0.1 mol Measurement substance: electron transporting agent 0.001 mol Solvent: 1 liter of CH ₂ Cl _{2 The} other electron transporting agent has a redox potential of −0.8 to −−.
The compound is not particularly limited as long as it is within the range of 1.4 V. For example, in addition to the diphenoquinone derivative represented by the general formula (2), the benzoquinone derivative represented by the general formula (3), an anthraquinone derivative, malononitrile Derivatives,
Thiopyran derivatives, trinitrothioxanthone derivatives,
Electron-accepting compounds such as fluorenone derivatives such as 3,4,5,7-tetranitro-9-fluorenone, dinitroanthracene derivatives, dinitroacridine derivatives, nitroantaraquinone derivatives, and dinitroanthraquinone derivatives.

The phthaloylpyrrolocholine derivative of the present invention
Considering the combination with (1 ′) , among the other electron transporting agents exemplified above, it is preferable to use a diphenoquinone derivative represented by the general formula (2) and a benzoquinone derivative represented by the general formula (3). preferable. Examples of the alkyl group corresponding to the groups ^{RA to RH} in the general formulas (2) and (3) include the same groups as described above. Examples of the aryl group include groups such as phenyl, tolyl, xylyl, naphthyl, anthryl, phenanthryl, fluorenyl, biphenylyl, o-terphenyl and the like. As an aralkyl group,
Examples include groups such as benzyl, benzhydryl, trityl, phenethyl and the like. Examples of the cycloalkyl group include, for example, cyclopropyl, cyclobutyl, cyclopentyl,
Examples thereof include groups having 3 to 8 carbon atoms such as cyclohexyl, cycloheptyl, and cyclooctyl. Examples of the amino group which may have a substituent include, for example, amino, monomethylamino, dimethylamino, monoethylamino, diethylamino and the like. Further, the groups R ^{A to} R ^D in the general formula (2) and the groups R ^{E to} R ^H in the general formula (3) are
It is preferable that two or more of the groups are the same, but the present invention is not limited thereto.

Specific examples of the diphenoquinone derivative (2) include, for example, 3,5-dimethyl-3 ′, 5′-di (t-butyl) -4,4 ′ represented by the following formula (2-1). -Diphenoquinone (redox potential -0.86 V), the following formula (2-2)
3,3 ′, 5,5′-tetra (t-butyl) represented by
-4,4'-diphenoquinone (redox potential -0.94
V), and 3,3′-dimethyl-5,5′-di (t-
Butyl) -4,4'-diphenoquinone and 3,5'-dimethyl-3 ', 5-di (t-butyl) -4,4'-diphenoquinone.

[0040]

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Specific examples of the benzoquinone derivative (3) include, for example, p-benzoquinone (redox potential -0.81 V) represented by the formula (3-1) and formula (3-2). 2,6-di (t-butyl) -p-benzoquinone (redox potential -1.31 V).

[0042]

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In the present invention, in addition to the above-mentioned electron transporting agents, other conventionally known electron transporting agents may be contained in the photosensitive layer. Examples of such other electron transporting agents include compounds represented by the following general formulas (ET1) to (ET17). (Electron transport agent) (ET1)

[0044]

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Wherein R ^e1 , R ^e2 , R ^e3 , R ^e4 and R
^e5 are the same or different, a hydrogen atom, an alkyl group which may have a substituent, an alkoxy group which may have a substituent,
It represents an aryl group which may have a substituent, an aralkyl group which may have a substituent, a phenoxy group which may have a substituent, or a halogen atom. ) (ET2)

[0046]

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(Where R ^e6 is an alkyl group, R ^e7 is an alkyl group which may have a substituent, an alkoxy group which may have a substituent, an aryl group which may have a substituent, Represents an aralkyl group, a halogen atom or a halogenated alkyl group which may have a group, γ represents an integer of 0 to 5. When γ is 2 or more, each ^{Re 7} may be different from each other. ) (ET3)

[0048]

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(In the formula, R ^e8 and R ^e9 are the same or different and each represents an alkyl group. Δ represents an integer of 1 to 4,
Represents an integer of 0 to 4. Note that when δ and ε is 2 or more, each R ^e8 and R ^e9 may be different. ) (ET4)

[0050]

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^Wherein R ^e10 represents an alkyl group, an aryl group, an aralkyl group, an alkoxy group, a halogenated alkyl group or a halogen atom.
Indicates an integer. When η is 2 or more, each ^{Re 10} may be different. ) (ET5)

[0052]

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(In the formula, R ^e11 represents an alkyl group, and σ represents an integer of 1 to 4. When σ is 2 or more, each R
^e11 may be different. ) (ET6)

[0054]

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(In the formula, R ^e12 and R ^e13 are the same or different and each represent a hydrogen atom, a halogen atom, an alkyl group, an aryl group, an aralkyloxycarbonyl group, an alkoxy group, a hydroxyl group, a nitro group or a cyano group. It represents an oxygen atom, a = N-CN group or a = C (CN) ₂ group.) (ET7)

[0056]

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^Wherein R ^e14 represents a hydrogen atom, a halogen atom, an alkyl group or a phenyl group which may have a substituent, and R ^e15 represents a halogen atom, an alkyl group which may have a substituent or Represents a phenyl group, an alkoxycarbonyl group, an N-alkylcarbamoyl group, a cyano group or a nitro group which may have a group, and λ represents an integer of 0 to 3.
When λ is 2 or more, each ^{Re 15} may be different from each other. ) (ET8)

[0058]

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(In the formula, θ represents an integer of 1 to 2.) (ET9)

[0060]

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(In the formula, R ^e16 and R ^e17 are the same or different and each represent a halogen atom, an alkyl group which may have a substituent, a cyano group, a nitro group, or an alkoxycarbonyl group. shows a third integer. Note, [nu or ξ is when 2 or more, each R ^e16 and R ^e17 may be different from each other.) (ET10)

[0062]

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(In the formula, R ^e18 and R ^e19 are the same or different and each represents a phenyl group, a polycyclic aromatic group or a heterocyclic group, and these groups may have a substituent.) ET11)

[0064]

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( ^Wherein R ^e20 represents an amino group, a dialkylamino group, an alkoxy group, an alkyl group or a phenyl group, and π represents an integer of 1-2. When π is 2,
Each R ^{e2 0} may be different from each other. ) (ET12)

[0066]

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( ^Wherein R ^e21 represents a hydrogen atom, an alkyl group,
It represents an aryl group, an alkoxy group or an aralkyl group. ) (ET13)

[0068]

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^Wherein R ^e22 represents a halogen atom, an alkyl group which may have a substituent, a phenyl group which may have a substituent, an alkoxycarbonyl group, an N-alkylcarbamoyl group, a cyano group or a nitro group. Represents an integer of 0 to 3. When μ is 2 or more, each ^{Re 22} may be different from each other.) (ET14)

[0070]

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[0071] (wherein, R ^e23 is a alkyl group or a substituted group may have a substituent indicates also aryl group, R ^e24 represents an alkyl group which may have a substituent, have a represents an aryl group or a group ^-O-R e24a. R e24a in the group, represents an aryl group which may have a an optionally substituted alkyl group or a substituted group. ) (ET15)

[0072]

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^Where R ^e25 , R ^e26 , R ^e27 ,
R ^e28, R ^e29, R ^e30 and R ^e31 represents an alkyl group, an aryl group, an aralkyl group, an alkoxy group, a halogen atom or a halogenated alkyl group the same or different. χ and φ are the same or different and represent an integer of 0 to 4. ) (ET16)

[0074]

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( ^Wherein R ^e32 and R ^e33 are the same or different and represent an alkyl group, an aryl group, an alkoxy group, a halogen atom or a halogenated alkyl group. Τ and ψ are the same or different and are each an integer of 0 to 4) In the electron transport agent exemplified above, examples of the alkyl group, the aryl group, the aralkyl group, and the cycloalkyl group include the same groups as described above. Examples of the alkoxy group include groups having 1 to 6 carbon atoms such as methoxy, ethoxy, n-propoxy, isopropoxy, t-butoxy, n-pentyloxy, and n-hexyloxy. Examples of the halogen atom include fluorine, chlorine, bromine and iodine. Examples of the halogenated alkyl group include groups in which a halogen atom such as fluorine, chlorine, bromine, or iodine is substituted at an arbitrary position of the alkyl group. Examples of the alkoxycarbonyl group include groups such as a methoxycarbonyl group. Examples of the aralkyloxycarbonyl group include groups such as a benzyloxycarbonyl group.
The alkoxy moiety in the alkoxyoxy group includes the same groups as the above-described alkoxy groups. The aralkyl moiety in the aralkyloxy group includes the same groups as the aralkyl groups described above.

Examples of the heterocyclic group include thienyl, furyl, pyrrolyl, pyrrolidinyl, oxazolyl, isoxazolyl, thiazolyl, isothiazolyl, imidazolyl, 2H-imidazolyl, pyrazolyl, triazolyl,
Examples include tetrazolyl, pyranyl, pyridyl, piperidyl, piperidino, 3-morpholinyl, morpholino, and thiazolyl. Further, it may be a heterocyclic group condensed with an aromatic ring.

Examples of the fused polycyclic group include naphthyl,
Phenanthryl, anthryl and the like. Examples of the N-alkylcarbamoyl group include those in which the alkyl moiety is any of the various alkyl groups described above. Examples of the dialkylamino group include those in which the alkyl moiety is any of the various alkyl groups described above. The two alkyls substituted on amino may be the same or different from each other.

Examples of the substituent which may be substituted on each of the above groups include a halogen atom, an amino group, a hydroxyl group, a carboxyl group which may be esterified, a cyano group, an alkyl group having 1 to 6 carbon atoms, Examples thereof include an alkoxy group having 1 to 6 carbon atoms and an alkenyl group having 2 to 6 carbon atoms which may have an aryl group. The substitution position of the substituent is not particularly limited.

Further, the electron transporting agents (ET1) to (ET1)
With or instead of 7), conventionally known electron transporting substances, that is, benzoquinone compounds, malononitriles, thiopyran compounds, tetracyanoethylene, 2,
4,8-Trinitrothioxanthone, dinitrobenzene, dinitroanthracene, dinitroacridine, nitroanthraquinone, dinitroanthraquinone, succinic anhydride, maleic anhydride, dibromomaleic anhydride and the like can also be used.

The charge generating agent, hole transporting agent and binder resin used in the electrophotographic photoreceptor of the present invention are as follows. [Charge Generator] Examples of the charge generator used in the present invention include compounds represented by the following general formulas (CG1) to (CG12).

(CG1) Metal-free phthalocyanine

[0082]

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(CG2) oxotitanyl phthalocyanine

[0084]

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(CG3) Perylene pigment

[0086]

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(Wherein, R ^g1 and R ^g2 are the same or different and represent a substituted or unsubstituted alkyl group, cycloalkyl group, aryl group, alkanoyl group or aralkyl group having 18 or less carbon atoms). ) Bisazo pigment

[0088]

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[Wherein Cp ¹ and Cp ² are the same or different and represent a coupler residue, and Q represents the following formulas (Q-1) to (Q-
8):

[0090]

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(Wherein, R ^g3 represents a hydrogen atom, an alkyl group, an aryl group or a heterocyclic group, and the alkyl group, the aryl group or the heterocyclic group may have a substituent.
Represents 0 or 1. )

[0092]

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[0093]

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(In the formula, R ^g4 and R ^g5 are the same or different and each represent a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, a halogen atom, an alkoxy group, an aryl group or an aralkyl group.)

[0095]

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[0096]

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[0097]

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(In the formula, R ^g6 represents a hydrogen atom, an ethyl group, a chloroethyl group or a hydroxyethyl group.)

[0099]

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Or

[0101]

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( ^Wherein , R ^g7 , R ^g8 and R ^g9 are the same or different and each represent a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, a halogen atom, an alkoxy group, an aryl group or an aralkyl group). Shows the group to be formed. (CG5) dithioketopyrrolopyrrole pigment

[0103]

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( ^Wherein R ^g10 and R ^g11 are the same or different and each represent a hydrogen atom, an alkyl group, an alkoxy group or a halogen atom, and R ^g12 and R ^g13 are the same or different and are a hydrogen atom, an alkyl group or an aryl group. (CG6) Metal-free naphthalocyanine pigment

[0105]

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^Wherein R ^g14 , R ^g15 , R ^g16 and R ^g14
g17 is the same or different and represents a hydrogen atom, an alkyl group, an alkoxy group or a halogen atom. (CG7) Metal naphthalocyanine pigment

[0107]

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^Wherein R ^g18 , R ^g19 , R ^g20 and R ^g20
g21 is the same or different and represents a hydrogen atom, an alkyl group, an alkoxy group or a halogen atom, and M represents Ti or V. ) (CG8) Squaraine pigment

[0109]

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( ^Wherein R ^g22 and R ^g23 are the same or different and each represent a hydrogen atom, an alkyl group, an alkoxy group or a halogen atom.) (CG9) Trisazo pigment

[0111]

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(Wherein Cp ³ , Cp ⁴ and Cp ⁵ are the same or different and represent a coupler residue.) (CG10) Indigo pigment

[0113]

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( ^Wherein , R ^g24 and R ^g25 are the same or different and each represent a hydrogen atom, an alkyl group or an aryl group, and Z represents an oxygen atom or a sulfur atom.) (CG11) Azulhenium pigment

[0115]

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( ^Wherein R ^g26 and R ^g27 are the same or different and each represent a hydrogen atom, an alkyl group or an aryl group.) (CG12) Cyanine pigment

[0117]

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(In the formula, R ^g28 and R ^g29 are the same or different and each represent a hydrogen atom, an alkyl group, an alkoxy group or a halogen atom, and R ^g30 and R ^g31 are the same or different and represent a hydrogen atom, an alkyl group or an aryl group. In the charge generators exemplified above, examples of the alkyl group, the alkoxy group, the aryl group, the aralkyl group, the alkanoyl group, the cycloalkyl group, and the heterocyclic group include the same groups as described above. The substituted or unsubstituted alkyl group having 18 or less carbon atoms is a group containing octyl, nonyl, decyl, dodecyl, tridecyl, pentadecyl, octadecyl and the like in addition to the above-mentioned alkyl group having 1 to 6 carbon atoms.

The substituents which may be substituted on the above groups include:
For example, a halogen atom, an amino group, a hydroxyl group, a carboxyl group which may be esterified, a cyano group, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, and 2 to 2 carbon atoms which may have an aryl group And 6 alkenyl groups. Cp ¹ , Cp ² , Cp ³ , Cp ⁴ and Cp
Examples of the coupler residue represented by ⁵ include groups represented by the following general formulas (Cp-1) to (Cp-11).

[0120]

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[0121]

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In each formula, R ^g32 represents a carbamoyl group, a sulfamoyl group, an allofanoyl group, an oxamoyl group, an anthraniloyl group, a carbazoyl group, a glycyl group, a hydantoyl group, a phthalamoyl group or a succinamoyl group. These groups include a halogen atom, a phenyl group which may have a substituent, a naphthyl group which may have a substituent, a nitro group, a cyano group, an alkyl group, an alkenyl group,
It may have a substituent such as a carbonyl group or a carboxyl group.

R ^g33 represents an atomic group necessary for forming an aromatic ring, a polycyclic hydrocarbon or a heterocyclic ring by condensing with a benzene ring, and these rings have the same substituents as described above. You may. R ^g34 represents an oxygen atom, a sulfur atom or an imino group. R ^g35 represents a divalent chain hydrocarbon group or an aromatic hydrocarbon group, and these groups may have the same substituent as described above.

R ^g36 represents an alkyl group, an aralkyl group, an aryl group or a heterocyclic group, and these groups may have the same substituent as described above. R ^g37 is required to form a heterocyclic ring together with a divalent chain hydrocarbon group or an aromatic hydrocarbon group, or with two nitrogen atoms in the above groups (Cp-1) to (Cp-11). Represents an atomic group, and these rings may have the same substituents as described above.

R ^g38 represents a hydrogen atom, an alkyl group, an amino group, a carbamoyl group, a sulfamoyl group, an allofanoyl group, a carboxyl group, an alkoxycarbonyl group, an aryl group or a cyano group, and the groups other than the hydrogen atom are the same as those described above. It may have a substituent. R ^g39 represents an alkyl group or an aryl group, and these groups may have the same substituent as described above.

Examples of the alkenyl group include those having 2 to 2 carbon atoms such as vinyl, allyl, 2-butenyl, 3-butenyl, 1-methylallyl, 2-pentenyl and 2-hexenyl.
And 6 alkenyl groups. In the above R ^g33 ,
Examples of the atomic group necessary to form an aromatic ring by condensing with a benzene ring include an alkylene group having 1 to 4 carbon atoms such as methylene, ethylene, trimethylene, and tetramethylene.

Examples of the aromatic ring formed by the condensation of R ^g33 and a benzene ring include a naphthalene ring, an anthracene ring, a phenanthrene ring, a pyrene ring, a chrysene ring, and a naphthacene ring. In R ^g33 , the atomic group necessary for condensing with a benzene ring to form a polycyclic hydrocarbon includes, for example, the alkylene group having 1 to 4 carbon atoms, or a carbazole ring, a benzocarbazole ring, or a dibenzofuran ring. And the like.

In R ^g33 , the atomic groups necessary for condensing with a benzene ring to form a heterocyclic ring include, for example, benzofuranyl, benzothiophenyl, indolyl,
H-indolyl, benzoxazolyl, benzothiazolyl, 1H-indolyl, benzimidazolyl, chromenil, chromanil, isochromanyl, quinolinyl, isoquinolinyl, cinnolinyl, phthalazinyl, quinazonyril, quinoxalinyl, dibenzofuranyl, carbazolyl, xanthenyl, acridinyl, phenanthrinyl Phenazinyl, phenoxazinyl, thianthrenyl and the like can be mentioned.

The aromatic heterocyclic group formed by the condensation of R ^g33 with a benzene ring includes, for example, thienyl,
Furyl, pyrrolyl, oxazolyl, isoxazolyl,
Examples include thiazolyl, isothiazolyl, imidazolyl, pyrazolyl, triazolyl, tetrazolyl, pyridyl and thiazolyl. Further, it may be a heterocyclic group condensed with another aromatic ring (for example, benzofuranyl, benzimidazolyl, benzoxazolyl, benzothiazolyl, quinolyl and the like).

In R ^g35 and R ^g37 , ^examples of the divalent chain hydrocarbon group include ethylene, trimethylene, and tetramethylene, and examples of the divalent aromatic hydrocarbon group include phenylene, naphthylene, and phenanthrylene. Is raised. In R ^g36 , ^examples of the heterocyclic group include pyridyl, pyrazyl, thienyl, pyranyl, indolyl and the like.

In R ^g37 , ^examples of the atomic group necessary for forming a heterocyclic ring with two nitrogen atoms include phenylene, naphthylene, phenanthrylene, ethylene, trimethylene, and tetramethylene. Examples of the aromatic heterocyclic group formed by the above R ^g37 and two nitrogen atoms include benzimidazole, benzo [f] benzimidazole, dibenzo [e, g] benzimidazole, benzopyrimidine and the like. These groups may have the same substituents as described above.

In the above R ^g38 , ^examples of the alkoxycarbonyl group include groups such as methoxycarbonyl, ethoxycarbonyl, propoxycarbonyl and butoxycarbonyl. In the present invention, in addition to the above-exemplified charge generating agents, for example, powders of inorganic photoconductive materials such as selenium, selenium-tellurium, selenium-arsenic, cadmium sulfide, amorphous silicon, pyrylium salts, anthanthrone-based pigments, Conventionally known charge generators such as phenylmethane pigments, sllen pigments, toluidine pigments, pyrazoline pigments, and quinacridone pigments can be used.

The charge generation agents exemplified above are used alone or in combination of two or more so as to have an absorption wavelength in a desired region. Among the above-described charge generating agents, in particular, a photoreceptor having a sensitivity in a wavelength region of 700 nm or more is required for a digital optical image forming apparatus such as a laser beam printer or a facsimile using a light source such as a semiconductor laser. Therefore, for example, phthalocyanine pigments such as metal-free phthalocyanine represented by the general formula (CG1) and oxotitanyl phthalocyanine represented by the general formula (CG2) are preferably used. The crystal form of the phthalocyanine pigment is not particularly limited, and various types can be used.

On the other hand, an image forming apparatus of an analog optical system such as an electrostatic copying machine using a white light source such as a halogen lamp requires a photosensitive member having sensitivity in the visible region. Perylene pigments represented by (CG3), bisazo pigments represented by general formula (CG4), and the like are preferably used. [Hole transport agent] Examples of the hole transport agent used in the present invention include compounds represented by the following general formulas (HT1) to (HT13).

(HT1)

[0136]

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(Wherein R ^h1 , R ^h2 , R ^h3 , R ^h4 , R ^h5 and R ^h6 are the same or different and each have a halogen atom, an alkyl group which may have a substituent, A and b are the same or different and represent an integer of 0 to 4, and c, d, e and f are the same or different and represent 0 to 5 of an aryl group which may have a substituent. When a, b, c, d, e or f is 2 or more, each of R ^h1 , R ^h2 , R ^h3 , R ^h4 , R ^h5 and R ^h6
May be different. ) (HT2)

[0138]

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(Wherein R ^h7 , R ^h8 , R ^h9 , R ^h10 and R ^h11 are the same or different and are each a halogen atom, an alkyl group which may have a substituent, an alkoxy group which may have a substituent, An aryl group which may have a group or a substituent is shown.
g, h, i and j are the same or different and each represents an integer of 0 to 5, and k represents an integer of 0 to 4. Note that g, h, i,
When j or k is 2 or more, each of R ^h7 , R ^h8 , R ^h9 , R
^h10 and R ^h11 may be different. ) (HT3)

[0140]

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(Wherein R^h12, R^h13, R^h14And R
^h15Are the same or different and have a halogen atom and
Alkyl group which may be substituted, alkoxy which may have a substituent
It represents an aryl group which may have a substituent or a substituent. R
^h16Has a halogen atom, cyano group, nitro group,
Alkyl group which may be substituted, alkoxy which may have a substituent
It represents an aryl group which may have a substituent or a substituent.
m, n, o and p are the same or different, and
Indicates a number. q shows the integer of 0-6. Note that m, n,
When o, p or q is 2 or more, each R^h12, R^h13, R
^h14, R^h15And R ^h16May be different. ) (HT4)

[0142]

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( ^Wherein R ^h17 , R ^h18 , R ^h19 and R ^h17)
h20 is the same or different and represents a halogen atom, an alkyl group which may have a substituent, an alkoxy group which may have a substituent or an aryl group which may have a substituent.
r, s, t and u are the same or different and each represent an integer of 0-5. When r, s, t or u is 2 or more,
Each of R ^h17 , R ^h18 , R ^h19 and R ^h20 may be different. ) (HT5)

[0144]

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(Wherein R ^h21 and R ^h22 are the same or different and each represent a hydrogen atom, a halogen atom, an alkyl group or an alkoxy group. R ^h23 , R ^h24 , R ^h25 and R
^h26 is the same or different and represents a hydrogen atom, an alkyl group or an aryl group. ) (HT6)

[0146]

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( ^Wherein , R ^h27 , R ^h28 and R ^h29 are the same or different and each represent a hydrogen atom, a halogen atom, an alkyl group or an alkoxy group). (HT7)

[0148]

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( ^Wherein R ^h30 , R ^h31 , R ^h32 and R ^h30)
h33 is the same or different and is a hydrogen atom, a halogen atom,
It represents an alkyl group or an alkoxy group. ) (HT8)

[0150]

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( ^Wherein R ^h34 , R ^h35 , R ^h36 , R ^h37
And R ^h38 are the same or different and each represent a hydrogen atom, a halogen atom, an alkyl group or an alkoxy group. ) (HT9)

[0152]

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[0153] (wherein, R ^H39 represents a hydrogen atom or an alkyl group, R ^h40, R ^h41 and R ^{h4 2} are the same or different and represent a hydrogen atom, a halogen atom, an alkyl group or an alkoxy group.) (HT10 )

[0154]

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[0155] (wherein, R ^h43, R ^h44 and R ^h45 are the same or different and represent a hydrogen atom, a halogen atom, an alkyl group or an alkoxy group.) (HT11)

[0156]

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( ^Wherein R ^h46 and R ^h47 are the same or different and each represent a hydrogen atom, a halogen atom, an alkyl group which may have a substituent or an alkoxy group which may have a substituent. R ^h48 And R ^h49 are the same or different,
It represents a hydrogen atom, an alkyl group which may have a substituent or an aryl group which may have a substituent. ) (HT12)

[0158]

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(Wherein R^h50, R^h51, R^h52,
R^h53, R^h54And R^h55Are the same or different
Alkyl group which may have a substituent, may have a substituent
An alkoxy group or an aryl group which may have a substituent;
Show. α represents an integer of 1 to 10, and v, w, x, y, z
And β are the same or different and represent an integer of 0 to 2. What
When v, w, x, y, z or β is 2, each
R^h50, R^h51, R^h52, R^h53, R ^h54And R^h55
May be different. ) (HT13)

[0160]

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( ^Wherein R ^h56 , R ^h57 , R ^h58 and R ^h58)
h59 is the same or different and is a hydrogen atom, a halogen atom,
Represents an alkyl group or an alkoxy group, and Φ represents the following group (Φ
-1), (Φ-2) or (Φ-3):

[0162]

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Is shown. In the above-described hole transporting agent, the alkyl group, the alkoxy group, the aryl group, the aralkyl group, and the halogen atom include the same groups as described above. Examples of the substituent which may be substituted on the above group include a halogen atom, an amino group, a hydroxyl group, a carboxyl group which may be esterified, a cyano group, an alkyl group having 1 to 6 carbon atoms, and a 1 to 1 carbon atom.
And an alkenyl group having 2 to 6 carbon atoms which may have 6 alkoxy groups and aryl groups. The substitution position of the substituent is not particularly limited.

In addition, the hole transport agents (HT1) to (HT1)
With or in place of 3), a conventionally known hole transporting substance, that is, an oxadiazole-based compound such as 2,5-di (4-methylaminophenyl) -1,3,4-oxadiazole, 9 Styryl compounds such as-(4-diethylaminostyryl) anthracene, carbazole compounds such as polyvinylcarbazole, organic polysilane compounds, pyrazoline compounds such as 1-phenyl-3- (p-dimethylaminophenyl) pyrazoline, hydrazone compounds, Nitrogen-containing cyclic compounds such as triphenylamine compounds, indole compounds, oxazole compounds, isoxazole compounds, thiazole compounds, thiadiazole compounds, imidazole compounds, pyrazole compounds, triazole compounds, and condensed polycyclic compounds Compounds and the like can also be used.

In the present invention, only one hole transporting agent may be used, or two or more hole transporting agents may be used in combination. Also,
When a hole transporting agent having a film-forming property such as polyvinyl carbazole is used, a binder resin is not necessarily required. [Binder Resin] As the binder resin for dispersing the above components, various resins conventionally used in the photosensitive layer can be used. For example, styrene-butadiene copolymer, styrene-acrylonitrile copolymer, styrene-
Maleic acid copolymer, acrylic copolymer, styrene-acrylic acid copolymer, polyethylene, ethylene-vinyl acetate copolymer, chlorinated polyethylene, polyvinyl chloride, polypropylene, ionomer, vinyl chloride-vinyl acetate copolymer, Polyester, alkyd resin, polyamide,
Thermoplastic resins such as polyurethane, polycarbonate, polyarylate, polysulfone, diallyl phthalate resin, ketone resin, polyvinyl butyral resin, polyether resin, polyester resin; silicone resin, epoxy resin, phenol resin, urea resin, melamine resin, and other crosslinkable Thermosetting resin; resins such as photo-curable resins such as epoxy acrylate and urethane-acrylate can be used.

In the photosensitive layer, in addition to the above-mentioned components, various additives known in the art, such as an antioxidant, a radical scavenger, a singlet quencher, and an ultraviolet absorber as long as the electrophotographic properties are not adversely affected. Agents, softeners, plasticizers, surface modifiers, extenders, thickeners, dispersion stabilizers, waxes, acceptors, donors, and the like.
Further, in order to improve the sensitivity of the photosensitive layer, a known sensitizer such as terphenyl, halonaphthoquinones, acenaphthylene and the like may be used in combination with the charge generator.

Next, a method for producing the electrophotographic photosensitive member of the present invention will be described. The single-layer type photoreceptor of the present invention comprises a phthaloylpyrrolocholine derivative (electron transporting agent) represented by the general formula (1), a charge generating agent, a binder resin, and if necessary, a hole transporting agent. It is formed by dissolving or dispersing in a solvent, applying the obtained coating liquid on a conductive substrate, and drying.

In the above-mentioned single-layer type photoreceptor, the charge generating agent may be blended in an amount of 0.1 to 50 parts by weight, preferably 0.5 to 30 parts by weight, based on 100 parts by weight of the binder resin. The electron transport agent is 5 parts by weight based on 100 parts by weight of the binder resin.
-100 parts by weight, preferably 10-80 parts by weight. Further, the hole transporting agent is a binder resin 100
5 to 500 parts by weight, preferably 25 to 2 parts by weight based on parts by weight
What is necessary is just to mix | blend in the ratio of 00 weight part. When the electron transporting agent and the hole transporting agent are used in combination, the total amount of the electron transporting agent and the hole transporting agent is 20 to 500 parts by weight, preferably 30 to 200 parts by weight, based on 100 parts by weight of the binder resin. It is appropriate to use parts by weight. Oite the photosensitive layer of single layer type, the general formula
Phthaloylpyrrolocholine derivative represented by (1 ') (electron transfer
And Okuzai), case of incorporating an electron-accepting compound, an electron accepting compound relative to the binder resin 100 parts by weight 0.1
It is appropriate to mix in an amount of from 40 to 40 parts by weight, preferably from 0.5 to 20 parts by weight.

The thickness of the photosensitive layer in the single-layer type photosensitive member is 5 to 5.
It is 100 μm, preferably 10 to 50 μm. The laminated photoreceptor of the present invention first forms a charge generation layer containing a charge generation agent on a conductive substrate by means such as vapor deposition or coating, and then forms a general formula on the charge generation layer.
The charge transport layer is prepared by applying a coating solution containing a phthaloylpyrrolocholine derivative (electron transporting agent) represented by (1) and a binder resin, and drying to form a charge transporting layer.

In the above-mentioned laminated type photoreceptor, the charge generating agent and the binder resin constituting the charge generating layer can be used in various ratios, and the charge generating agent is used with respect to 100 parts by weight of the binder resin. 5 to 1000 parts by weight, preferably 30 to 50 parts
It is appropriate to mix at a ratio of 0 parts by weight. When the charge generating layer contains a hole transporting agent, the proportion of the hole transporting agent is suitably from 10 to 500 parts by weight, preferably from 50 to 200 parts by weight, based on 100 parts by weight of the binder resin. .

The electron transporting agent and the binder resin constituting the charge transporting layer can be used in various ratios within a range that does not hinder charge transport and a range that does not crystallize. An electron transporting agent is added to 100 parts by weight of the binder resin so that the generated charges can be easily transported.
It is suitable to mix at a ratio of from 500 to 500 parts by weight, preferably from 25 to 200 resin. When the charge-transporting layer contains an electron-accepting compound, the proportion of the electron-accepting compound is 0.1 to 40 parts by weight, preferably 0.5 to 20 parts by weight, based on 100 parts by weight of the binder resin. Is appropriate.

The thickness of the photosensitive layer in the laminated photoreceptor is such that the charge generation layer has a thickness of about 0.01 to 5 μm, preferably 0.1 to 5 μm.
The thickness is about 3 μm, and the thickness of the charge transport layer is about 2 to 100 μm, preferably about 5 to 50 μm. In the case of a single-layer type photoreceptor, between the conductive substrate and the photosensitive layer, and in the case of the laminated type photoreceptor, between the conductive substrate and the charge generating layer, between the conductive substrate and the charge transport layer, or A barrier layer may be formed between the generation layer and the charge transport layer as long as the characteristics of the photoreceptor are not impaired. Further, a protective layer may be formed on the surface of the photoconductor.

As the conductive substrate on which the photosensitive layer is formed, various conductive materials can be used.
For example, iron, aluminum, copper, tin, platinum, silver, vanadium, molybdenum, chromium, cadmium, titanium, nickel, palladium, indium, stainless steel, brass and other simple metals, and plastic materials on which the above metals are deposited or laminated, Glasses coated with aluminum iodide, tin oxide, indium oxide, and the like can be given.

The shape of the conductive substrate may be sheet-like or drum-like depending on the structure of the image forming apparatus to be used. The substrate itself has conductivity or the surface of the substrate has conductivity. What is necessary is just to have the property. The conductive substrate preferably has a sufficient mechanical strength when used. When the photosensitive layer is formed by a coating method, a charge generating agent, a charge transporting agent, a binder resin, and the like described above, together with a suitable solvent, may be used in a known manner, such as a roll mill, a ball mill, an attritor, a paint shaker, or What is necessary is just to disperse and mix using a sonic disperser or the like to prepare a dispersion, apply it by a known means, and dry it.

As the solvent for preparing the dispersion, various organic solvents can be used, for example, alcohols such as methanol, ethanol, isopropanol and butanol; and aliphatic carbons such as n-hexane, octane and cyclohexane. Hydrogen; aromatic hydrocarbons such as benzene, toluene and xylene; halogenated hydrocarbons such as dichloromethane, dichloroethane, chloroform, carbon tetrachloride and chlorobenzene; ethers such as dimethyl ether, diethyl ether, tetrahydrofuran, ethylene glycol dimethyl ether and diethylene glycol dimethyl ether Ketones such as acetone, methyl ethyl ketone and cyclohexanone; esters such as ethyl acetate and methyl acetate; dimethyl formaldehyde, dimethyl formamide, dimethyl sulfone Kishido and the like. These solvents are used alone or in combination of two or more.

Further, in order to improve the dispersibility of the charge transporting agent and the charge generating agent and the smoothness of the surface of the photosensitive layer, a surfactant is used.
A leveling agent or the like may be used.

[0177]

[Manufacture of electrophotographic photoreceptor]

Example 1 A metal-free phthalocyanine pigment (CG1) was used as a charge generating agent.
Formula (HT1-1) as a hole transport agent:

[0178]

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[0179] The benzidine derivative represented by the formula as an electron transporting agent phthaloyl pyrrolo choline derivative represented by (1'-1) (melting point 157 ° C.), have a predetermined redox potential
As the other electron transporting agent represented by the formula (3-1)
Zoquinone derivatives were each used. 5 parts by weight of the charge generating agent, 50 parts by weight of the hole transporting agent, 30 parts by weight of the electron transporting agent, 10 parts by weight of the other electron transporting agent, and 100 parts by weight of the binder resin (polycarbonate) are mixed with 800 parts by weight of a solvent (tetrahydrofuran). The mixture was mixed and dispersed in a ball mill for 50 hours to prepare a coating solution for a single-layer photosensitive layer. Next, this coating solution is applied on a conductive substrate (aluminum pipe) by dip coating, and dried with hot air at 100 ° C. for 60 minutes to obtain a single-layer electrophotographic photosensitive member having a photosensitive layer having a thickness of 15 to 20 μm. A body (for a digital light source) was manufactured.

[0180]

[0181]

[0182]

[0183]

[0184]

[0185]

[0186] In the other electron-transporting agent having an oxidation reduction potential of Examples 2-4 plants constant, in place of benzoquinone derivative represented by the formula (3-1), Table by the formula (3-2) Benzoquinone Derivatives (Examples)
2), in addition to using the diphenoquinone derivative represented by the formula (2-1) (diphenoquinone derivative represented by Example 3) or the formula (2-2) (Example 4) Example 1
Similarly, a single-layer type electrophotographic photoreceptor (for digital light source)
Manufactured .

[0187]

Comparative Examples 1 and 10 A metal-free phthalocyanine pigment (CG1) was used as a charge generator.
Benzidine represented by the above formula (HT1-1) as a hole transport agent
Derivative, and the electron transport agent formula (ET13-1):

[0189]

Embedded image

The naphthoquinone derivative represented by the formula (Comparative Example 1) or the diphenoquinone derivative represented by the formula (2-1) (Comparative Example 10) was used. The above charge generation
5 parts by weight of the agent, 50 parts by weight of the hole transporting agent, and 30 parts by weight of the electron transporting agent
Parts and 100 parts by weight of binder resin (polycarbonate)
Together with 800 parts by weight of solvent (tetrahydrofuran)
Mixing and dispersion for 50 hours using a
A coating solution was prepared. Next, this coating solution is applied to a conductive substrate (A
Luminium tube) by dip coating
It is dried with hot air at 00 ° C. for 60 minutes to form a film having a thickness of 15 to 20 μm.
A single-layer type electrophotographic photosensitive member having a photosensitive layer (for a digital light source) was manufactured. Comparative Examples 2 and 11 Comparative Example 2 was carried out in the same manner as Comparative Example 1 except that titanyl phthalocyanine pigment (CG2) was used as the charge generator , and Comparative Example 11 was carried out in the same manner as Comparative Example 10 in the same manner.
Each produced a single-layer type electrophotographic photoreceptor (for digital light source).

Comparative Examples 3 and 13 A metal-free phthalocyanine pigment (CG1) was used as a charge generator.
Naphthoquinone derivative represented by the formula as an electron transporting agent (ET13-1) (Comparative Example 3) or the formula (2-1)
The diphenoquinone derivative represented (Comparative Example 13)
Each was used. 100 parts by weight of the charge generating agent and binding
100 parts by weight of resin (polyvinyl butyral)
Ball mill with 2000 parts by weight of (trahydrofuran)
For 50 hours to form a coating solution for the charge generation layer.
Made. Next, this coating solution is applied to a conductive substrate (aluminum).
Dip-coating method at 100 ℃
Drying with hot air for 60 minutes to form a 1 μm-thick charge generation layer
did. Next, 100 parts by weight of the electron transport agent and the binder tree
100 parts by weight of fat (polycarbonate) in a solvent (tolue)
B) Mix with 800 parts by weight in a ball mill for 50 hours
By dispersing, a coating solution for a charge transport layer was prepared. Then
Apply this coating solution on the charge generation layer by dip coating.
Coated, dried with hot air at 100 ° C for 60 minutes,
m of a charge transport layer, and a layered electrophotographic photosensitive member (digital
For a barrel light source).

Comparative Examples 4 and 14 Formula (CG3-1):

Embedded image Comparative Example 4 except that a perylene pigment represented by
In the same manner as in Comparative Example 1,
A single-layer type electrophotographic photosensitive member (for an analog light source) was manufactured in the same manner as in Comparative Example 10 .

Comparative Examples 5 and 16 A perylene face represented by the above formula (CG3-1) was used as a charge generating agent.
Comparative Example 5 was the same as Comparative Example 3 except that a charge was used.
Then , a laminated electrophotographic photosensitive member (for an analog light source) was manufactured in the same manner as in Comparative Example 13 for Comparative Example 16 .

Comparative Examples 6 to 9 A single-layer type electrophotographic photosensitive member (digital) was prepared in the same manner as in Examples 1 to 4 , except that the naphthoquinone derivative represented by the above formula (ET13-1) was used as the electron transporting agent. (For light source).
Other electron transporting agents having a predetermined oxidation-reduction potential include a benzoquinone derivative represented by the formula (3-1) (Comparative Example 6) and a benzoquinone derivative represented by the formula (3-2) ( Comparative Example 7), a diphenoquinone derivative represented by the formula (2-1) (Comparative Example 8) or a diphenoquinone derivative represented by the formula (2-2) (Comparative Example 9) was used.

Comparative Example 12 A single-layer electrophotographic photosensitive member (for a digital light source) was produced in the same manner as in Comparative Example 1, except that the electron transporting agent was not used. Comparative Example 15 A single-layer type electrophotographic photoreceptor (for an analog light source) was produced in the same manner as in Comparative Example 4 except that the electron transporting agent was not blended.

Of the photoreceptors obtained in the above Examples and Comparative Examples, the photoreceptor for digital light source was subjected to the following electrical property test (A), and the photoreceptor for analog light source was subjected to the following electrical property test (A). B) was performed, and the electrical characteristics of each photoconductor were evaluated. Electric property test (A) Applying an applied voltage to the surface of the photoreceptor using a drum sensitivity tester manufactured by GENTEC, and applying +700 to the surface
Was charged. Next, a wavelength 780 nm (half-width 20 nm, light intensity 16 μW / light) extracted from white light of a halogen lamp as an exposure light source using a bandpass filter.
cm ² ) of monochromatic light on the surface of the photoreceptor (irradiation time: 80 milliseconds) for exposure, and the surface potential at 330 milliseconds after the start of the exposure is determined as the residual potential Vr (unit:
V).

Electric property test (B) White light (light intensity 147) of a halogen lamp as an exposure light source
μW / cm ² ) and the irradiation time was set to 50 milliseconds, except that the residual potential V
r (V) was measured. The smaller the value of the residual potential Vr, the higher the sensitivity.

The types of the charge generating agent, the hole transporting agent, the electron transporting agent, and the other electron transporting agent having a predetermined oxidation-reduction potential used in Examples 1 to 4 and Comparative Examples 1 to 16 were determined based on the electrical characteristics. The results are shown in Tables 1 and 2 together with the test results. The types of the charge generating agent, the hole transporting agent and the electron transporting agent are indicated by the numbers assigned to the respective compounds.

[0199]

[Table 1]

[0200]

[Table 2]

Examples 5 to 13 Comparative Example 1 was carried out except that a phthaloylpyrrolocholine derivative represented by the above formula (1-2) (melting point: 212 to 213 ° C.) was used as the electron transporting agent. (Digital light source
Example 6 in the same manner as in Comparative Example 2 (digital
Example 7 is a comparative example
Example 8 in the same manner as in Example 3 (for digital light source)
Is the same as in Comparative Example 4 (for an analog light source),
Is the same as in Comparative Example 5 (for an analog light source).
Example 10 is the same as Example 1 (for digital light source).
In the manner described above, the eleventh embodiment corresponds to the second embodiment (digital optical
In the same manner as in the case of
Example 13 in the same manner as (for digital light source)
In the same manner as in Example 4 (for digital light source) was prepared <br/> electrophotographic photoreceptor, respectively. Next, the electrical characteristics test (A) was performed for the photosensitive member for the digital light source, and the electrical characteristics test (B) was performed for the photosensitive member for the analog light source, to evaluate the electrical characteristics of each photosensitive member.

Table 3 shows the types of the charge generating agent, the hole transporting agent and the electron transporting agent used in Examples 5 to 13 together with the test results of the electrical characteristics.

[0203]

[Table 3]

As is clear from Tables 1 to 3, the photoreceptors of Examples 1 to 13 using the phthaloylpyrrolocholine derivative represented by the general formula (1) or (1 ') as the electron transporting agent, Also, as compared with the corresponding photosensitive members of Comparative Examples 1 to 16, the residual potential Vr is small and the sensitivity is excellent. The photoreceptor using the phthaloylpyrrolocholine derivative (1) in combination with another electron transporting agent having a predetermined oxidation-reduction potential has a further smaller residual potential Vr and is more excellent in sensitivity.

[0205]

The electrophotographic photoreceptor of the present invention has the general formula (1)
Alternatively, since the photosensitive layer containing the phthaloylpyrrolocholine derivative represented by (1 ′) is provided, the sensitivity is high. Accordingly, the electrophotographic photoreceptor of the present invention has a specific function and effect that contributes to speeding up and improving performance of various image forming apparatuses such as an electrostatic copying machine and a laser beam printer.

[Brief description of the drawings]

FIG. 1 Traction voltage (V) for determining oxidation-reduction potential
6 is a graph showing the relationship between the current and the current (μA).

FIG. 2 is a ¹ H-NMR spectrum of a phthaloylpyrrolocholine derivative (1′-1) used in Examples.

FIG. 3 is an infrared absorption (IR) spectrum of a phthaloylpyrrolocholine derivative (1′-1) used in Examples.

FIG. 4 is a ¹ H-NMR spectrum of a phthaloylpyrrolocholine derivative (1-2) used in Examples.

FIG. 5 is an infrared absorption (IR) spectrum of a phthaloylpyrrolocholine derivative (1-2) used in Examples.

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-8-334911 (JP, A) JP-A-9-15881 (JP, A) JP-A-9-40672 (JP, A) 297610 (JP, A) JP-A-5-323639 (JP, A) JP-A-7-271067 (JP, A) JP-A-5-297611 (JP, A) JP-A-5-45908 (JP, A) JP-A-9-319110 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G03G 5/00 CA (STN)

Claims (3)

(57) [Claims] 1. An electrophotographic photosensitive member having a photosensitive layer provided on a conductive substrate, wherein the photosensitive layer has a general formula (1): (In the formula, R ¹ represents an alkyl group, an aryl group, an aralkyl group, an acyl Motoma other represents a cyano group.) The electrophotographic photosensitive member characterized by containing a phthaloyl pyrrolo choline derivative represented by the. 2. An electrophotographic device comprising a photosensitive layer provided on a conductive substrate.
An optical member, wherein the photosensitive layer is one general formula (1 '): ## STR2 ## (Wherein R ^{1 ′} is an alkyl group, an aryl group, an aralkyl
Group, acyl group, alkoxycarbonyl group, aryloxy
A cyclocarbonyl group, an aralkyloxycarbonyl group or
Shows a cyano group. And phthaloyl pyrrolo choline derivative represented by), the electrophotographic redox potential is characterized by containing an electron transfer agent is -0.8 to-1.4V photoreceptor. 3. The method according to claim 1, wherein the electron transporting agent has a general formula (2): (Wherein, R ^A , R ^B , R ^C and R ^D are the same or different and each represents a hydrogen atom, an alkyl group, an aryl group, an aralkyl group, a cycloalkyl group, an alkoxy group or an amino group optionally having a substituent. Or a diphenoquinone derivative represented by the following general formula (3): (Wherein, R ^E , R ^F , R ^G and R ^H are the same or different and each represents a hydrogen atom, an alkyl group, an aryl group, an aralkyl group, a cycloalkyl group, an alkoxy group or an amino which may have a substituent. The electrophotographic photoreceptor according to claim 2, which is a benzoquinone derivative represented by the following formula: