JP4217588B2 - Electrophotographic photosensitive member, process cartridge, and electrophotographic apparatus - Google Patents

Description

  The present invention relates to an electrophotographic photosensitive member, a process cartridge, and an electrophotographic apparatus, and more specifically, an electrophotographic photosensitive member containing a specific charge transporting substance and a specific additive compound in a photosensitive layer, and a process cartridge having the electrophotographic photosensitive member. And an electrophotographic apparatus.

  In recent years, electrophotographic photoreceptors used in electrophotographic technology are organic electrophotographic photoreceptors using organic materials because of their advantages such as easy photo film formation and low cost production. Has been put into practical use, and active research and development is still underway. Among the organic electrophotographic photoreceptors, the function-separated organic electrophotographic photoreceptor, in which the photosensitive layer is separated into a charge generation layer and a charge transport layer, has good electrophotographic characteristics, and a wide range of organic materials for each layer. Since a suitable material can be selected from the above, it has been widely used. However, further improvement is desired in terms of high sensitivity, high durability, and image stability during repeated use as an organic electrophotographic photoreceptor.

  In response to these problems, it has been proposed to use a high molecular weight charge transport material for increasing the sensitivity and durability of an electrophotographic photoreceptor (see, for example, Patent Documents 1 and 2). The high molecular weight charge transporting material described in Patent Document 1 is a high molecular weight charge transporting material having a molecular weight distribution produced by polymerizing a low molecular weight monomer, and this charge transporting material is used for an electrophotographic photoreceptor. This indicates that high sensitivity can be achieved by improving durability and improving charge transport ability. Further, Patent Document 1 proposes a method of separating a polymer type high molecular weight charge transporting material containing a large number of triphenylamines into molecular weight fractions and narrowing the molecular weight distribution of the polymer type high molecular weight charge transporting material. Among them, it is described that the charge transporting ability can be improved by narrowing the molecular weight distribution of the polymer type high molecular weight charge transporting substance. Also in this Patent Document 1, an electrophotographic photoreceptor containing a polymer type high molecular weight charge transporting material having a molecular weight distribution obtained by separation is disclosed. In particular, Patent Document 2 describes that the durability of an electrophotographic photoreceptor is improved by using a polymer-type polymer charge transport material.

In addition, for the purpose of improving the potential stability during repeated use over a long period of time, a proposal has been made to contain an additive compound in the photosensitive layer (see, for example, Patent Document 3). Further, proposals have been made to use an additive compound together with a high molecular weight charge transport material in the photosensitive layer (see, for example, Patent Document 4, Patent Document 5, and Patent Document 6). Patent Documents 4 to 6 describe that image stability during repeated use is improved when a polymer charge transport material and an additive compound having a specific structure are used for the charge transport layer.
International Publication Number WO00 / 078843 International Publication Number WO99 / 32537 Japanese Patent Publication No. 50-33857 JP 9-319106 A JP 9-319112 A Japanese Patent Laid-Open No. 9-319121

  However, the electrophotographic photoreceptors described in Patent Documents 1 and 2 are polymer-type high-molecular-weight charge transport materials, and are susceptible to oxidative degradation. It may not be. Further, in the electrophotographic photoreceptors described in Patent Documents 4 to 6, since a polymer type high molecular weight charge transport material is used as the resin constituting the photosensitive layer, the solvent contained in the coating solution for the photosensitive layer Insufficient compatibility of the functional group having a charge transport function may not be uniformly disposed in the photosensitive layer, resulting in insufficient sensitivity, and the lifetime of carriers generated in the charge transport material upon light irradiation may be reduced. Long and optical memory may become large.

  The object of the present invention is to solve the above-mentioned problems, and to contain a specific charge transporting substance and a specific additive compound in the photosensitive layer, so that the mechanical strength of wear resistance is high and the optical memory is not used. It is an object to provide an electrophotographic photosensitive member that is small and has good and stable electrophotographic characteristics upon repeated use over a long period of time, and stably provides images of good quality even during repeated use.

That is, the present invention has a support and a photosensitive layer formed on the support, an electrophotographic photosensitive member the photosensitive layer contains a charge transport material and additive compound,
The following formula (1) with respect to the total mass of the charge transport material contained in the photosensitive layer:

(In formula (1) , Ar _{101 to} Ar ₁₀₈ each independently represents a substituted or unsubstituted monovalent aromatic hydrocarbon ring group, or a substituted or unsubstituted monovalent aromatic heterocyclic group. Z _{11 to} Z ₁₅ each independently represents a substituted or unsubstituted divalent aromatic hydrocarbon ring group or a substituted or unsubstituted divalent aromatic heterocyclic group.
In having a structure shown, and the proportion of the molecular weight of the charge transporting substance is 1500 to 4,000 is 1 00% by weight and,
At least one additive compound contained in the photosensitive layer, the following equation (1-1)

(In the formula (1-1) , tBu is a tertiary butyl group, R ₁ is a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted hydroxyl group, a substituted or unsubstituted ester group, A substituted or unsubstituted amino group or a substituted or unsubstituted cycloalkyl group is shown.)
Or a compound having a structure represented by the following formula (1-2)

(In Formula (1-2) , R ₂ and R ₃ are each independently a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted hydroxyl group, a substituted or unsubstituted ester group. Represents a substituted or unsubstituted amino group or a substituted or unsubstituted cycloalkyl group.)
And a compound having a structure represented by :
The mass (X _1-1 ) of the compound having the structure represented by the above formula (1-1) contained in the photosensitive layer and the mass of the compound having the structure represented by the above formula (1-2) (X ₁₋ sum of the mass of _{2) (in X} 1-1 ₊ X _1-2), the ratio of the values to the total weight of the charge transport material included in the photosensitive layer _{(Y 1) ((X 1-1} + X 1-2) / _{Y 1)} is Ru electrophotographic photoreceptor der, characterized in that 0.05 to 0.20.

Further, the present invention has a support and a photosensitive layer formed on the support, an electrophotographic photosensitive member the photosensitive layer contains a charge transport material and additive compound,
With respect to the total mass of the charge transport material contained in the photosensitive layer, the following formula (2)

(In the formula (2) , Ar _{201 to} Ar ₂₀₉ each independently represent a substituted or unsubstituted monovalent aromatic hydrocarbon ring group or a substituted or unsubstituted monovalent aromatic heterocyclic group. Z _{21 to} Z ₂₆ each independently represent a substituted or unsubstituted divalent aromatic hydrocarbon ring group or a substituted or unsubstituted divalent aromatic heterocyclic group.
In having a structure shown, and the proportion of the molecular weight of the charge transporting substance is 1500 to 4,000 is 1 00% by weight and,
At least one additive compound contained in the photosensitive layer, the following equation (2-1)

(In the formula (2-1) , tBu is a tertiary butyl group, R ₄ is a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted hydroxyl group, a substituted or unsubstituted ester group, A substituted or unsubstituted amino group or a substituted or unsubstituted cycloalkyl group is shown.)
Or a compound having a structure represented by the following formula (2-2)

(In Formula (2-2) , R ₅ and R ₆ are each independently a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted hydroxyl group, a substituted or unsubstituted ester group. Represents a substituted or unsubstituted amino group or a substituted or unsubstituted cycloalkyl group.)
And a compound having a structure represented by :
The mass (X _2-1 ) of the compound having the structure represented by the above formula (2-1) and the mass of the compound having the structure represented by the above formula (2-2) contained in the photosensitive layer (X _{2− 2} ) The value of the ratio of the total mass (X _2-1 + X _2-2 ) to the total mass (Y ₂ ) of the charge transport material contained in the photosensitive layer ((X _2-1 + X _2-2 ) / _{Y 2)} is Ru electrophotographic photoreceptor der, characterized in that 0.05 to 0.20.

Further, the present invention has a support and a photosensitive layer formed on the support, an electrophotographic photosensitive member the photosensitive layer contains a charge transport material and additive compound,
With respect to the total mass of the charge transport material contained in the photosensitive layer, the following formula (3)

(In Formula (3) , Ar _{301 to} Ar ₃₁₀ each independently represent a substituted or unsubstituted monovalent aromatic hydrocarbon ring group or a substituted or unsubstituted monovalent aromatic heterocyclic group. Z _{31 to} Z ₃₇ each independently represent a substituted or unsubstituted divalent aromatic hydrocarbon ring group or a substituted or unsubstituted divalent aromatic heterocyclic group.
In having a structure shown, and the proportion of the molecular weight of the charge transporting substance is 1500 to 4,000 is 1 00% by weight and,
At least one additive compound contained in the photosensitive layer, the following equation (3-1)

(In the formula (3-1) , tBu is a tertiary butyl group, R ₇ is a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted hydroxyl group, a substituted or unsubstituted ester group, A substituted or unsubstituted amino group or a substituted or unsubstituted cycloalkyl group is shown.)
Or a compound having a structure represented by the following formula (3-2)

(In Formula (3-2) , R ₈ and R ₉ are each independently a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted hydroxyl group, a substituted or unsubstituted ester group. Represents a substituted or unsubstituted amino group or a substituted or unsubstituted cycloalkyl group.)
And a compound having a structure represented by :
The mass (X _3-1 ) of the compound having the structure represented by the above formula (3-1) and the mass of the compound having the structure represented by the above formula (3-2) (X _{3 −3} ) contained in the photosensitive layer. ₂ ) the value of the ratio of the total mass (X _3-1 + X _3-2 ) to the total mass (Y ₃ ) of the charge transport material contained in the photosensitive layer ((X _3-1 + X _3-2 ) / _{Y 3)} is Ru electrophotographic photoreceptor der, characterized in that 0.05 to 0.20.

Further, the present invention has a support and a photosensitive layer formed on the support, an electrophotographic photosensitive member the photosensitive layer contains a charge transport material and additive compound,
With respect to the total mass of the charge transport material contained in the photosensitive layer, the following formula (4)

(In formula (4) , Ar _{401 to} Ar ₄₁₁ each independently represent a substituted or unsubstituted monovalent aromatic hydrocarbon ring group or a substituted or unsubstituted monovalent aromatic heterocyclic group. Z _{41 to} Z ₄₈ each independently represent a substituted or unsubstituted divalent aromatic hydrocarbon ring group or a substituted or unsubstituted divalent aromatic heterocyclic group.
In having a structure shown, and the proportion of the molecular weight of the charge transporting substance is 1500 to 4,000 is 1 00% by weight and,
At least one additive compound contained in the photosensitive layer, the following equation (4-1)

(In the formula (4-1) , tBu is a tertiary butyl group, R ₁₀ is a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted hydroxyl group, a substituted or unsubstituted ester group, A substituted or unsubstituted amino group or a substituted or unsubstituted cycloalkyl group is shown.)
Or a compound having a structure represented by the following formula (4-2)

(In Formula (4-2) , R ₁₁ and R ₁₂ are each independently a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted hydroxyl group, a substituted or unsubstituted ester group. Represents a substituted or unsubstituted amino group or a substituted or unsubstituted cycloalkyl group.)
And a compound having a structure represented by :
The mass (X _4-1 ) of the compound having the structure represented by the above formula (4-1) contained in the photosensitive layer and the mass of the compound having the structure represented by the above formula (4-2) (X _{4− 2} ) The value of the ratio of the total mass (X _4-1 + X _4-2 ) to the total mass (Y ₄ ) of the charge transport material contained in the photosensitive layer ((X _4-1 + X _4-2 ) / _{Y 4)} is Ru electrophotographic photoreceptor der, characterized in that 0.05 to 0.20.

Further, the present invention has a support and a photosensitive layer formed on the support, an electrophotographic photosensitive member the photosensitive layer contains a charge transport material and additive compound,
The following formula (5) with respect to the total mass of the charge transport material contained in the photosensitive layer:

(In formula (5) , Ar _{501 to} Ar ₅₁₂ each independently represent a substituted or unsubstituted monovalent aromatic hydrocarbon ring group, or a substituted or unsubstituted monovalent aromatic heterocyclic group. And Z _{51 to} Z ₅₉ each independently represent a substituted or unsubstituted divalent aromatic hydrocarbon ring group or a substituted or unsubstituted divalent aromatic heterocyclic group.
In having a structure shown, and the proportion of the molecular weight of the charge transporting substance is 1500 to 4,000 is 1 00% by weight and,
At least one additive compound contained in the photosensitive layer, the following equation (5-1)

(In the formula (5-1) , tBu is a tertiary butyl group, R ₁₃ is a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted hydroxyl group, a substituted or unsubstituted ester group, A substituted or unsubstituted amino group or a substituted or unsubstituted cycloalkyl group is shown.)
Or a compound having a structure represented by the following formula (5-2)

(In Formula (5-2) , R ₁₄ and R ₁₅ are each independently a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted hydroxyl group, a substituted or unsubstituted ester group. Represents a substituted or unsubstituted amino group or a substituted or unsubstituted cycloalkyl group.)
And a compound having a structure represented by :
The mass (X _5-1 ) of the compound having the structure represented by the above formula (5-1) and the mass of the compound having the structure represented by the above formula (5-2) contained in the photosensitive layer (X _{5− 2} ) The value of the ratio of the total mass (X _5-1 + X _5-2 ) to the total mass (Y ₅ ) of the charge transport material contained in the photosensitive layer ((X _5-1 + X _5-2 ) / _{Y 5)} is, Ru electrophotographic photoreceptor der, characterized in that 0.05 to 0.20.

In addition, the present invention integrally supports any of the above electrophotographic photosensitive members and at least one means selected from the group consisting of a charging means, a developing means, and a cleaning means, and is detachably attached to the electrophotographic apparatus main body. Ru process cartridge der, characterized in that it.

Further, the present invention is one of the electrophotographic photosensitive member described above, a charging means, an exposure means, Ru electrophotographic apparatus der characterized by having a developing means and a transfer means.

  In the present invention, by using the electrophotographic photosensitive member, it has high mechanical strength, high wear resistance, high light resistance, and good electrophotographic characteristics, so that it has a good quality even when used repeatedly for a long time. An electrophotographic photoreceptor that forms an image can be provided.

  The charge transport material in the present invention refers to a high molecular weight charge transport material (Macro-Molecular Charge Transfer Materials) that can be described by a specific chemical structural formula, which is different from a polymer type high molecular weight charge transport material having a molecular weight distribution.

  The charge transport material contained in the photosensitive layer has a structure represented by any one of the above formulas (1) to (5) and has a molecular weight of 1500 or more and 4000 or less. Although it may contain a molecular weight charge transporting substance and a high molecular weight charge transporting substance at the same time, it has a structure represented by the above formula (1) from the viewpoint of mechanical strength and electrophotographic characteristics of the electrophotographic photosensitive member, In addition, the proportion of the charge transport material having a molecular weight of 1500 or more and 4000 or less is preferably 90% by mass or more and 100% by mass or less, more preferably based on the total mass of the charge transport material contained in the photosensitive layer. It is 95 mass% or more and 100 mass% or less, More preferably, it is 100 mass%.

  Alternatively, the proportion of the charge transport material having the structure represented by the above formula (2) and having a molecular weight of 1500 or more and 4000 or less is 90 masses with respect to the total mass of the charge transport material contained in the photosensitive layer. % To 100% by mass, more preferably 95% to 100% by mass, and even more preferably 100% by mass.

  Alternatively, the proportion of the charge transport material having the structure represented by the above formula (3) and having a molecular weight of 1500 or more and 4000 or less is 90 masses with respect to the total mass of the charge transport material contained in the photosensitive layer. % To 100% by mass, more preferably 95% to 100% by mass, and even more preferably 100% by mass.

  Alternatively, the proportion of the charge transport material having the structure represented by the above formula (4) and having a molecular weight of 1500 or more and 4000 or less is 90 masses with respect to the total mass of the charge transport material contained in the photosensitive layer. % To 100% by mass, more preferably 95% to 100% by mass, and even more preferably 100% by mass.

  Alternatively, the proportion of the charge transport material having the structure represented by the above formula (5) and having a molecular weight of 1500 or more and 4000 or less is 90 masses with respect to the total mass of the charge transport material contained in the photosensitive layer. % To 100% by mass, more preferably 95% to 100% by mass, and even more preferably 100% by mass.

Ar _{101 to} Ar _{108 in} the above formula (1), Ar _{201 to} Ar _{209 in} the above formula (2), Ar _{301 to} Ar _{310 in} the above formula (3), and Ar ₄₀₁ in the above formula (4). ˜Ar ₄₁₁ and the substituted or unsubstituted monovalent aromatic hydrocarbon ring group represented by Ar _{501 to} Ar ₅₁₂ in the above formula (5) include a phenyl group, a naphthyl group, an anthracenyl group, and a pyrenyl group. Examples of the substituted or unsubstituted monovalent aromatic heterocyclic group include a pyridyl group, an indole group, a quinolinyl group, a benzofuranyl group, a dibenzofuranyl group, a benzothiophenyl group, and a dibenzothiophenyl group. Of these, a phenyl group, a naphthyl group, a pyridyl group, a benzofuranyl group, and a benzothiophenyl group are preferable. These substituents include a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, an aromatic hydrocarbon ring group having any of 3 to 12 carbon atoms, and 1 to 8 carbon atoms. Any of alkoxy groups, halogen atoms, fluorinated alkyl groups, cyano groups, nitro groups, etc. are mentioned. Among them, hydrogen atom, methyl group, ethyl group, methoxy group, fluorine atom, chlorine atom, bromine atom, A fluoromethyl group is preferred.

Z _{11 to} Z _{15 in} the above formula (1), Z _{21 to} Z _{26 in} the above formula (2), Z _{31 to} Z _{37 in} the above formula (3), Z _{41 to} Z in the above formula (4). ₄₈ , and substituted or unsubstituted divalent aromatic hydrocarbon ring groups represented by Z _{51 to} Z ₅₉ in the above formula (5) include a phenylene group, a biphenylene group, a terphenylene group, a fluorenylene group, and a naphthylene group. , Anthracenylene group, pyrenylene group, etc., and substituted or unsubstituted divalent aromatic heterocyclic groups include pyridinylene group, indolinylene group, quinolinylene group, benzofuranylene group, dibenzofuranylene group, benzothiophenylene group, And dibenzothiophenylene group. In addition, the above-described divalent aromatic hydrocarbon ring group or aromatic heterocyclic group is an alkylene group, an alkylidene group, a substituted or non-substituted group having a single bond, a substituted or unsubstituted carbon number of 1 to 4 carbon atoms. Those formed by linking with a silylene group having a substituted silicon number of 1 to 4, an oxygen atom, or a sulfur atom are also substituted or unsubstituted divalent aromatic hydrocarbon ring groups, or substituted or Examples thereof include an unsubstituted divalent aromatic heterocyclic group. Among substituted or unsubstituted divalent aromatic hydrocarbon ring groups or substituted or unsubstituted divalent aromatic heterocyclic groups, biphenylene group, fluorenylene group, pyridinylene group, dibenzofuranylene group, benzothiophenylene Groups are preferred.

More preferably, Z _{11 to} Z ₁₅ in the above formula (1) are a substituted or unsubstituted biphenylene group, a substituted or unsubstituted dibenzofuranylene group, or a substituted or unsubstituted dibenzothiophenylene group,
Alternatively, Z _{21 to} Z ₂₆ in the above formula (2) are a substituted or unsubstituted biphenylene group, a substituted or unsubstituted dibenzofuranylene group, or a substituted or unsubstituted dibenzothiophenylene group,
Alternatively, Z _{31 to} Z ₃₇ in the above formula (3) are a substituted or unsubstituted biphenylene group, a substituted or unsubstituted dibenzofuranylene group, or a substituted or unsubstituted dibenzothiophenylene group,
Alternatively, Z _{41 to} Z ₄₈ in the above formula (4) are a substituted or unsubstituted biphenylene group, a substituted or unsubstituted dibenzofuranylene group, or a substituted or unsubstituted dibenzothiophenylene group,
Alternatively, Z _{51 to} Z ₅₉ in the above formula (5) are a substituted or unsubstituted biphenylene group, a substituted or unsubstituted dibenzofuranylene group, or a substituted or unsubstituted dibenzothiophenylene group.

More preferably, at least one of Z _{11 to} Z ₁₅ in the formula (1) is a substituted or unsubstituted dibenzofuranylene group or a substituted or unsubstituted dibenzothiophenylene group, and other Z ₁₁ to Z ₁₅ is a substituted or unsubstituted biphenylene group,
Alternatively, among Z _{21 to} Z ₂₆ in the formula (2), at least one is a substituted or unsubstituted dibenzofuranylene group or a substituted or unsubstituted dibenzothiophenylene group, and the other Z ₂₁ to Z ₂₆ Z ₂₆ is a substituted or unsubstituted biphenylene group,
Alternatively, at least one of Z _{31 to} Z ₃₇ in the formula (3) is a substituted or unsubstituted dibenzofuranylene group or a substituted or unsubstituted dibenzothiophenylene group, and the other Z ₃₁ to Z ₃₇ Z ₃₇ is a substituted or unsubstituted biphenylene group,
Alternatively, at least one of Z _{41 to} Z _{48 in} the above formula (4) is a substituted or unsubstituted dibenzofuranylene group or a substituted or unsubstituted dibenzothiophenylene group, and the other Z ₄₁ to Z ₄₈ Z ₄₈ is a substituted or unsubstituted biphenylene group,
Alternatively, at least one of Z _{51 to} Z ₅₉ in the formula (5) is a substituted or unsubstituted dibenzofuranylene group, or a substituted or unsubstituted dibenzothiophenylene group, and the other Z ₅₁ to Z ₅₉ Z ₅₉ is a substituted or unsubstituted biphenylene group.

  Examples of the substituent of these divalent aromatic hydrocarbon ring group or divalent aromatic heterocyclic group include a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, and 3 to 12 carbon atoms. An aromatic hydrocarbon ring group that is any of the above, an alkoxy group having any one of 1 to 8 carbon atoms, a halogen atom, a fluorinated alkyl group, a cyano group, a nitro group, etc., among them, a hydrogen atom, A methyl group, ethyl group, propyl group, methoxy group, ethoxy group, fluorine atom, chlorine atom, bromine atom and trifluoromethyl group are preferred.

  Next, specific examples of the charge transport material of the present invention will be given, but the present invention is not necessarily limited to the presented structure.

  The molecular weight of the charge transport material in the present invention is preferably 1500 or more and 4000 or less, more preferably 1500 or more and 3500 or less.

  The charge transport material in the present invention is characterized by being a high-molecular-weight charge transport material having a high unity represented only by a specific chemical structural formula. . Accordingly, it is preferable to use a charge transport material synthesized by a sequential synthesis method in which the synthesis method used in the production of the low molecular weight charge transport material is repeated. The sequential synthesis method is a synthesis method in which a single compound is formed as a main product by a chemical reaction between a raw material and a reaction target in a multi-step process. Unlike the method, it is possible to selectively produce a charge transport material having such a high unity that there is no molecular weight distribution.

  As a synthesis reaction used in the sequential synthesis method, a synthesis method used in the production of a conventional low molecular charge transport material is used. That is, the Ullmann reaction or a synthesis method using a metal catalyst is used. In addition, multi-step synthesis may be produced sequentially and continuously, and a purification step may be inserted between the steps from the end of one synthesis step to the next step synthesis. In addition, after the final step, a conventionally used purification method can be used. In other words, treatment with adsorbents such as activated clay, activated carbon, silica and alumina, column chromatography with silica or alumina, etc., purification with gel permeation column chromatography using polystyrene fine particles, recrystallization and crystallization, etc. A purification procedure according to may be used.

  Next, although the manufacture example of the charge transport material in this invention is shown, this invention is not limited to these.

(Production Example 1) Production of Exemplary Compound (CT-10) of Charge Transport Material <Production of bis (2,4-dimethylphenyl) amine>
In a 1 L three-necked reaction vessel equipped with a condenser and a mechanical stirrer, 133 g (1.1 mol) of 2,4-dimethylphenylamine, 185 g (1.0 mol) of 1-bromo-2,4-dimethylbenzene, palladium acetate 11.2 g (0.05 mol), 2-tert-butylphosphinoyl-2-methylpropane 32.4 g (0.2 mol), tripotassium phosphate 212 g (1.0 mol), dimethylformamide 500 mL, nitrogen gas Under an atmosphere, it was heated in an oil bath and refluxed for 12 hours. After completion of the reaction, the mixture was allowed to cool to room temperature, extracted with toluene / water, washed with aqueous hydrochloric acid, and then the organic layer was distilled under reduced pressure to obtain the desired bis (2,4-dimethylphenyl) amine. The yield of the obtained compound was 189 g, and the yield was 84%. The obtained compound was measured using an elemental analyzer (CHN coder MT-5, manufactured by YANACO Corporation). In addition, the unit of the actual measurement value and calculation value by the following elemental analysis is the mass%. Actual value: C, 85.24, H, 8.53, N, 6.63 (calculated value: C, 85.28, H, 8.50, N, 6.22).

<Production of bis (2,4-dimethylphenyl) [4- (bromophenyl) phenyl] amine>
In a 2 L three-necked reaction vessel equipped with a condenser and a mechanical stirrer, 112.5 g (0.5 mol) of (2,4-dimethylphenyl) amine, 156 g (0.5 mol) of 4,4′-dibromobiphenyl, acetic acid Put 5.6 g (0.025 mol) of palladium, 27.7 g (0.05 mol) of bis (diphenylphosphino) ferrocene, 63.7 g (0.7 mol) of tert-butoxy sodium, and 800 mL of xylene. Heated in bath and refluxed for 5 hours. After completion of the reaction, the mixture was allowed to cool to room temperature, extracted with toluene / water, washed with aqueous hydrochloric acid, and then the organic layer was distilled under reduced pressure and purified with a silica gel column (developing solvent hexane / toluene = 2: 1). The target (bis (2,4-dimethylphenyl) [4- (bromophenyl) phenyl] amine) was obtained, and the yield of the obtained compound was 155.2 g, and the yield was 68% by mass. The compound was measured using an elemental analyzer similar to that described above Actual value: C, 73.44, H, 5.62, N, 2.98 (calculated value: C, 73.68, H, 5.74) , N, 3.07).

<Production of bis (2,4-dimethylphenyl) (4- {4-[(2,4-dimethylphenyl) amino] phenyl} phenyl) amine>
Into a 1 L three-necked reaction vessel equipped with a cooling tube and a mechanical stirrer, 91.3 g (0.2 mol) of (bis (2,4-dimethylphenyl) [4- (bromophenyl) phenyl] amine, 2,4- Dimethylphenylamine 36.3 g (0.3 mol), palladium acetate 2.24 g (0.01 mol), bis (diphenylphosphino) ferrocene 11.1 g (0.02 mol), tert-butoxy sodium 26.9 g (0.28 mol) ), 500 mL of xylene was added, heated in an oil bath in a nitrogen gas atmosphere, and refluxed for 3 hours.After the reaction, the mixture was allowed to cool to room temperature, extracted with toluene / water, washed with hydrochloric acid, and then the organic layer was washed. Distilled under reduced pressure and purified with a silica gel column (developing solvent hexane / toluene = 1: 1) to obtain the desired bis (2,4-dimethyl). Phenyl) (4- {4-[(2,4-dimethylphenyl) amino] phenyl} phenyl) amine was obtained, and the yield of the obtained compound was 83.4 g and the yield was 84 mass%. The obtained compound was measured using the same elemental analyzer as described above Actual values: C, 87.03, H, 7.26, N, 5.71 (calculated values: C, 87.05, H, 7 .31, N, 5.64).

<Production of bis (2,4-dimethylphenyl) [4- (4-{(2,4-dimethylphenyl) [4- (4-bromophenyl) phenyl] amino} phenyl) phenyl] amine>
Into a 1 L three-necked reaction vessel equipped with a condenser and a mechanical stirrer, bis (2,4-dimethylphenyl) (4- {4-[(2,4-dimethylphenyl) amino] phenyl} phenyl) amine 49. 7 g (0.1 mol), 4,4′-dibromobiphenyl 31.2 g (0.1 mol), palladium acetate 1.13 g (0.005 mol), bis (diphenylphosphino) ferrocene 5.54 g (0.01 mol), 13.4 g (0.14 mol) of tert-butoxy sodium and 300 mL of xylene were added, heated in an oil bath under a nitrogen gas atmosphere, and refluxed for 5 hours. After completion of the reaction, the mixture was allowed to cool to room temperature, extracted with toluene / water, washed with aqueous hydrochloric acid, and then the organic layer was distilled under reduced pressure and purified with a silica gel column (developing solvent hexane / toluene = 2: 1). The target bis (2,4-dimethylphenyl) [4- (4-{(2,4-dimethylphenyl) [4- (4-bromophenyl) phenyl] amino} phenyl) phenyl] amine was obtained. The yield of the obtained compound was 50.9 g, and the yield was 70% by mass. The measured value of the obtained compound was measured using the same elemental analyzer as described above. Found: C, 79.26, H, 5.98, N, 3.83 (calculated: C, 79.22, H, 5.96, N, 3.85).

<Production of (2,4-dimethylphenyl) {8-[(2,4dimethylphenyl) amino] dibenzo [b, d] furan-2-yl} amine>
In a 500 mL three-necked reaction vessel equipped with a condenser and a mechanical stirrer, 65.2 g (0.2 mol) of 2,8-dibromodibenzofuran, 72.6 g (0.6 mol) of 2,4-dimethylphenylamine, palladium acetate 2.24 g (0.01 mol), tri (o-tolyl) phosphine 12.2 g (0.04 mol), tert-butoxy sodium 51.8 g (0.54 mol), and xylene 300 mL were placed in an oil bath under a nitrogen gas atmosphere. And refluxed for 5 hours. After completion of the reaction, an excess amount of 2,4-dimethylphenylamine and the solvent were distilled off by distillation under reduced pressure, allowed to cool to room temperature, extracted with toluene / water, washed with aqueous hydrochloric acid, and then the organic layer was evaporated with reduced pressure. Distillation and recrystallization gave the desired (2,4-dimethylphenyl) {8-[(2,4dimethylphenyl) amino] dibenzo [b, d] furan-2-yl} amine. The yield of the obtained compound was 71.5 g, and the yield was 88% by mass. The obtained compound was measured using the same elemental analyzer as described above. Found: C, 82.68, H, 6.44, N, 6.92 (calculated values: C, 82.73, H, 6.45, N, 6.89).

<Production of Exemplary Compound (CT-10) for Charge Transport Material>
A 500 mL three-necked reaction vessel equipped with a condenser and a mechanical stirrer was charged with bis (2,4-dimethylphenyl) [4- (4-{(2,4-dimethylphenyl) [4- (4-bromophenyl)]. Phenyl] amino} phenyl) phenyl] amine 36.4 g (0.05 mol), (2,4-dimethylphenyl) {8-[(2,4dimethylphenyl) amino] dibenzo [b, d] furan-2-yl } 10.2 g (0.025 mol) of amine, 0.57 g (0.0025 mol) of palladium acetate, 3.0 g (0.01 mol) of biphenyl-2-yl-di-tert-butylphosphine, sodium tert-butoxy 7 g (0.07 mol) and 200 mL of xylene were added, heated in an oil bath under a nitrogen gas atmosphere, and refluxed for 4 hours. After completion of the reaction, the mixture is allowed to cool to room temperature, extracted with toluene / water, washed with aqueous hydrochloric acid, and then the organic layer is evaporated under reduced pressure and purified with a silica gel column (developing solvent hexane / toluene = 1: 1). To obtain the target charge transport material shown by the exemplary compound (CT-10). The yield of the obtained compound was 39.1 g, and the yield was 89% by mass. The obtained compound was measured using the same elemental analyzer as described above. Actual value: C, 84.80, H, 5.81, N, 4.83 (calculated value: C, 84.85, H, 5.85, N, 4.79). In addition, mass spectrometry of the obtained compound was performed using a laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF-MASS) apparatus (REFLEX III, manufactured by BRUKER, matrix; 9-nitroanthracene). The measurement results of the mass spectrum obtained at this time are shown in FIG. In FIG. 1, the peak of the exemplary compound (CT-10) as a charge transport material was observed at m / e = 1699.1. The other peaks observed around m / e = 1699.1 are due to the isotope of the exemplary compound (CT-10) of the charge transport material. The horizontal axis of the mass spectrum represents the mass-to-charge ratio (product ion mass (m) / product ion charge valence (z)), and the vertical axis represents the detected product ion intensity.

(Production Example 2) Production of Exemplary Compound (CT-17) of Charge Transport Material <(2,4-Dimethylphenyl) {8-[(2,4dimethylphenyl) amino] dibenzo [b] benzo [b] thiophene- Production of 2-yl} amine>
In a 500 mL three-necked reaction vessel equipped with a condenser and a mechanical stirrer, 68.4 g (0.2 mol) of 2,8-dibromodibenzothiophene, 72.6 g (0.6 mol) of 2,4-dimethylphenylamine, acetic acid 2.24 g (0.01 mol) of palladium, 12.2 g (0.04 mol) of tri (o-tolyl) phosphine, 51.8 g (0.54 mol) of tert-butoxy sodium, and 300 mL of xylene were placed in a nitrogen gas atmosphere. Heated in bath and refluxed for 5 hours. After completion of the reaction, an excess amount of 2,4-dimethylphenylamine and the solvent were distilled off by distillation under reduced pressure, allowed to cool to room temperature, extracted with toluene / water, washed with aqueous hydrochloric acid, and then the organic layer was evaporated with reduced pressure. Distillation and recrystallization gave the desired (2,4-dimethylphenyl) {8-[(2,4dimethylphenyl) amino] dibenzo [b] benzo [b] thiophen-2-yl} amine. The yield of the obtained compound was 71.0 g, and the yield was 84% by mass. The obtained compound was measured using the same elemental analyzer as described above. Actual value: C, 79.60, H, 6.24, N, 6.52 (calculated value: C, 79.58, H, 6.20, N, 6.63).

<Production of Exemplary Compound (CT-17) for Charge Transport Material>
A 500 mL three-necked reaction vessel equipped with a condenser and a mechanical stirrer was charged with bis (2,4-dimethylphenyl) [4- (4-{(2,4-dimethylphenyl) [4- (4-bromophenyl)]. Phenyl] amino} phenyl) phenyl] amine 36.4 g (0.05 mol), (2,4-dimethylphenyl) {8-[(2,4 dimethylphenyl) amino] dibenzo [b] benzo [b] thiophene-2 -Il} amine 10.6 g (0.025 mol), palladium acetate 0.57 g (0.0025 mol), biphenyl-2-yl-di-tert-butylphosphine 3.0 g (0.01 mol), tert-butoxy sodium 6.7 g (0.07 mol) and 200 mL of xylene were added, heated in an oil bath under a nitrogen gas atmosphere, and refluxed for 4 hours. After completion of the reaction, the mixture is allowed to cool to room temperature, extracted with toluene / water, washed with aqueous hydrochloric acid, and then the organic layer is evaporated under reduced pressure and purified with a silica gel column (developing solvent hexane / toluene = 1: 1). To obtain the target charge transport material shown by the exemplary compound (CT-17). The yield of the obtained compound was 37.3 g, and the yield was 87% by mass. The obtained compound was measured using the same elemental analyzer as described above. Found: C, 86.80, H, 6.40, N, 4.86 (calculated value: C, 86.78, H, 6.46, N, 4.90). Moreover, mass spectrometry of the obtained compound was performed using the apparatus similar to the above-mentioned. The measurement result of the mass spectrum obtained at this time is shown in FIG. In FIG. 2, the peak of the exemplary compound (CT-17) as a charge transport material was observed at m / e = 1715.4. The other peaks observed around m / e = 1715.4 are due to the isotope of the exemplary compound (CT-17) of the charge transport material.

Production Example 3 Production of Compound (CT-39) as an Example of Charge Transport Material <Production of (2,4-Dimethylphenyl) -p-tolylamine>
In a 1 L three-necked reaction vessel equipped with a condenser and a mechanical stirrer, 133 g (1.1 mol) of 2,4-dimethylphenylamine, 171 g (1.0 mol) of 1-bromo-4-methylbenzene, 11. 2 g (0.05 mol), 2-tert-butylphosphinoyl-2-methylpropane 32.4 g (0.2 mol), tripotassium phosphate 212 g (1.0 mol), and dimethylformamide 500 mL were placed under a nitrogen gas atmosphere. The mixture was heated in an oil bath and refluxed for 12 hours. After completion of the reaction, the mixture was allowed to cool to room temperature, extracted with toluene / water, washed with aqueous hydrochloric acid, and then the organic layer was distilled under reduced pressure to obtain the desired (2,4-dimethylphenyl) -p-tolylamine. The yield of the obtained compound was 189.5 g, and the yield was 88% by mass. The obtained compound was measured using the same elemental analyzer as described above. Actual measurement value: C, 85.27, H, 8.09, N, 6.64 (calculated value: C, 85.26, H, 8.11, N, 6.63).

<Production of (4′-bromobiphenyl-4-yl)-(2,4-dimethylphenyl) -p-tolylamine>
To a 2 L three-necked reaction vessel equipped with an air cooling tube and a mechanical stirrer, 105.7 g (0.5 mol) of (2,4-dimethylphenyl) -p-tolylamine, 4′-bromo-4-iodobiphenyl 215. 4 g (0.6 mol), 50 g of copper powder, 60 g of potassium carbonate, and 600 mL of o-dichlorobenzene were added and heated in an oil bath for 12 hours. After completion of the reaction, the mixture was allowed to cool to room temperature, solids were removed by filtration, and extracted with toluene / water. After depressurizingly distilling a solvent from an organic layer, it refine | purifies in a silica gel column (developing solvent hexane / toluene = 2: 1), The target (4'-bromobiphenyl-4-yl)-(2,4-dimethyl) is carried out. Phenyl) -p-tolylamine was obtained. The yield of the obtained compound was 165.9 g, and the yield was 75% by mass. The obtained compound was measured using the same elemental analyzer as described above. Found: C, 73.33, H, 5.48, N, 3.17 (calculated values: C, 73.30, H, 5.47, N, 3.17).

<Production of N ⁴ , N ^{4 ′} -bis (2,4-dimethylphenyl) -N ⁴ -p-tolylbiphenyl-4,4′-diamine>
To a 1 L three-necked reaction vessel equipped with a condenser and a mechanical stirrer, 88.5 g (0.2 mol) of (4′-bromobiphenyl-4-yl)-(2,4-dimethylphenyl) -p-tolylamine, 2,4-dimethylphenylamine 26.7 g (0.22 mol), palladium acetate 2.2 g (0.01 mol), bis (diphenylphosphino) ferrocene 11.1 g (0.02 mol), tert-butoxy sodium 26.8 g (0.28 mol) and 400 mL of xylene were added, heated in an oil bath under a nitrogen gas atmosphere, and refluxed for 5 hours. After completion of the reaction, the mixture was allowed to cool to room temperature, extracted with toluene / water, washed with aqueous hydrochloric acid, and then the organic layer was distilled under reduced pressure and purified with a silica gel column (developing solvent hexane / toluene = 1: 1). The desired N ⁴ , N ^{4 ′} -bis (2,4-dimethylphenyl) -N ⁴ -p-tolylbiphenyl-4,4′-diamine was obtained. The yield of the obtained compound was 71.4 g, and the yield was 74% by mass. The obtained compound was measured using the same elemental analyzer as described above. Found: C, 87.05, H, 7.14, N, 5.81 (calculated values: C, 87.10, H, 7.10, N, 5.80).

<N ^{4 '-} (-4- 4'- bromo-biphenyl-yl) ^{-N 4,} N ^4' - preparation of bis ^{(2,4-dimethylphenyl)} -N 4-p-tolyl-biphenyl-4,4'-diamine >
To a 2 L three-necked reaction vessel equipped with an air cooling tube and a mechanical stirrer, (N ⁴ , N ^{4 ′} -bis (2,4-dimethylphenyl) -N ⁴ -p-tolylbiphenyl-4,4′-diamine was added. 48.3 g (0.1 mol), 39.5 g (0.11 mol) of 4′-bromo-4-iodobiphenyl, 20 g of copper powder, and 200 mL of o-dichlorobenzene were added and heated in an oil bath for 12 hours. After cooling to room temperature, the solids were removed by filtration, extracted with toluene / water, and the solvent was distilled off from the organic layer under reduced pressure, followed by purification with a silica gel column (developing solvent hexane / toluene = 2: 1). performed, N ⁴ object ^'- (4'-bromo-biphenyl-yl) ^{-N 4,} N ^4' - bis ^{(2,4-dimethylphenyl)} -N 4-p-tolyl-biphenyl-4,4'- Diamine The yield of the obtained compound was 45.0 g, and the yield was 63% by mass, and the obtained compound was measured using the same elemental analyzer as described above, measured values: C, 78.88, H, 5.69, N, 3.96 (calculated values: C, 79.09, H, 5.79, N, 3.92).

<Production of N ⁴ , N ^{4 ′} -bis (2,4-dimethylphenyl) -biphenyl-4,4′-diamine>
In a 1 L three-necked reaction vessel equipped with a condenser and a mechanical stirrer, 62.4 g (0.2 mol) of 4,4′-dibromobiphenyl, 72.6 g (0.6 mol) of 2,4-dimethylphenylamine, acetic acid 2.24 g (0.01 mol) of palladium, 12.2 g (0.04 mol) of tri (o-tolyl) phosphine, 51.8 g (0.54 mol) of tert-butoxy sodium, and 300 mL of xylene were placed in a nitrogen gas atmosphere. Heated in bath and refluxed for 5 hours. After completion of the reaction, an excess amount of 2,4-dimethylphenylamine and the solvent were distilled off by distillation under reduced pressure, allowed to cool to room temperature, extracted with toluene / water, washed with aqueous hydrochloric acid, and then the organic layer was evaporated with reduced pressure. distillation, recrystallization purposes of ^N 4, N ^{4 '-} biphenyl-4,4'-diamine - bis (2,4-dimethylphenyl). The yield of the obtained compound was 62.7 g, and the yield was 80% by mass. The obtained compound was measured using the same elemental analyzer as described above. Found: C, 85.66, H, 7.18, N, 7.16 (calculated values: C, 85.67, H, 7.19, N, 7.14).

<Production of Exemplary Compound (CT-39) for Charge Transport Material>
In a 500 mL three-necked reaction vessel equipped with a condenser and a mechanical stirrer, N ^{4 ′} -(4′-bromobiphenyl-4-yl) -N ⁴ , N ^{4 ′} -bis (2,4-dimethylphenyl)- N ⁴ -p-tolylbiphenyl-4,4′-diamine 35.7 g (0.05 mol), N ⁴ , N ^{4 ′} -bis (2,4-dimethylphenyl) -biphenyl-4,4′-diamine9. 8 g (0.025 mol), palladium acetate 0.57 g (0.0025 mol), biphenyl-2-yl-di-tert-butylphosphine 3.0 g (0.01 mol), tert-butoxy sodium 6.7 g (0. 07 mol) and 200 mL of xylene were added, heated in an oil bath under a nitrogen gas atmosphere, and refluxed for 4 hours. After completion of the reaction, the mixture is allowed to cool to room temperature, extracted with toluene / water, washed with aqueous hydrochloric acid, and then the organic layer is evaporated under reduced pressure and purified with a silica gel column (developing solvent hexane / toluene = 1: 1). To obtain the target charge transport material shown by the exemplified compound (CT-39). The yield of the obtained compound was 34.4 g, and the yield was 83% by mass. The obtained compound was measured using the same elemental analyzer as described above. Actual value: C, 88.40, H, 6.51, N, 5.09 (calculated value: C, 88.37, H, 6.56, N, 5.07). Moreover, mass spectrometry of the obtained compound was performed using the apparatus similar to the above-mentioned. The measurement result of the mass spectrum obtained at this time is shown in FIG. In FIG. 3, the peak of the exemplary compound (CT-39) as a charge transport material was observed at m / e = 1573.3. The other peaks observed around m / e = 1573.3 are attributed to the isotope of the exemplary compound (CT-39) of the charge transport material.

  At least one of the additive compounds in the present invention is represented by the following formula (A)

Wherein tBu is a tertiary butyl group, R _A is a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted hydroxyl group, a substituted or unsubstituted ester group, a substituted or unsubstituted An amino group or a substituted or unsubstituted cycloalkyl group is indicated.)
Or a compound having a structure represented by the following formula (B)

Wherein R _B1 and R _B2 are each independently a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted hydroxyl group, a substituted or unsubstituted ester group, a substituted or unsubstituted group An amino group or a substituted or unsubstituted cycloalkyl group.)
The compound which has a structure shown by is used.

  Specific examples of the compound having the structure represented by the above formula (A) or the compound having the structure represented by the above formula (B) used as an additive compound of the present invention will be given below, but the structure shown is not necessarily presented. It is not limited to.

  In the above formulas (AO-1) to (AO-8), tBu represents a tertiary butyl group, and n in the above formula (AO-11) represents the number of repeating structural units. The number average molecular weight (Mn) of the above formula (AO-11) is preferably 3000 or more and 5000 or less.

  Among the above additive compounds, compounds having the structures of (AO-2), (AO-6), (AO-7), (AO-8), (AO-10), and (AO-11) are particularly preferable. .

Sum of the mass of the mass of the compound having the mass of the compound having the structure represented by the formula contained in the photosensitive layer (A) and (X _A) a structure represented by the formula _{(B) (X B) (} X A The value ((X _A + X _B ) / Y) of the ratio + X _B ) to the total mass (Y) of the charge transport material is preferably 0.05 or more and 0.20 or less, more preferably 0.05 or more. 0.15 or less. The above formula (1) contained in the photosensitive layer having the total mass of the mass of the compound having the structure represented by the above formula (A) contained in the photosensitive layer and the mass of the compound having the structure represented by the above formula (B). ) To (5), and an additive compound is contained when the ratio of the molecular weight of the charge transport material having a molecular weight of 1500 to 4000 is less than 0.05. The effect of reducing the optical memory due to this is not fully exhibited. The above formula (1) contained in the photosensitive layer having the total mass of the mass of the compound having the structure represented by the above formula (A) contained in the photosensitive layer and the mass of the compound having the structure represented by the above formula (B). ) To (5), and the ratio of the mass ratio of the charge transport material having a molecular weight of 1500 or more and 4000 or less exceeds 0.20, the sensitivity is deteriorated. .

  At this time, if the additive compound is contained in the photosensitive layer so as to satisfy the range of the above-mentioned ratio, only the compound having the structure represented by the above formula (A) has the structure represented by the above formula (B). Or a compound having a structure represented by the above formula (A) and a compound having a structure represented by the above formula (B) may be contained.

  In addition, for the purpose of improving electrophotographic characteristics, in addition to a compound having a structure represented by the above formula (A) or a compound having a structure represented by the above formula (B) of the present invention, one or more kinds It is also possible to contain other additive compounds. Especially, it is particularly effective when used in combination with an additive compound selected from (AO-1) to (AO-11). In this case, the mixing ratio is arbitrary and can be optimized depending on the process conditions, environment, etc. when the electrophotographic photosensitive member is used.

  By using a photosensitive layer containing a specific charge transport material and a specific additive compound in the present invention, high sensitivity of the electrophotographic photosensitive member is achieved, and potential stability during repeated use over a long period of time, That is, the point that the image stability is excellent is considered as follows.

  Even when the charge transporting material having a specific structure used in the present invention is used alone, an electrophotographic photosensitive member with good sensitivity and relatively small potential fluctuation due to repeated use can be obtained. By adding a compound having the structure represented by the formula (B) or a compound having the structure represented by the formula (B), a more stable potential is exhibited over a long period of time. Can be provided for a longer period of time. Although the cause of this has not been elucidated in detail, a compound having a structure represented by the above formula (A) or a compound having a structure represented by the above formula (B) with respect to a charge transport material having a specific structure Light that is said to be generated by the retention of carriers in the photosensitive layer, because the interaction between the two and the molecules is large, and it is easy for the molecules of each other to be placed closer to each other. It seems that the memory can be made very small.

  Hereinafter, the structure of the electrophotographic photosensitive member used in the present invention will be described.

  The photosensitive layer of the electrophotographic photoreceptor of the present invention includes a single layer type photosensitive layer containing a charge generating material and a charge transporting material in a single layer, a charge transporting layer containing a charge transporting material, and a charge generating material. Either a function-separated type (laminated type) photosensitive layer that is functionally separated into the charge generating layer to be used may be used, but from the viewpoint of electrophotographic characteristics, a function-separated type (laminated type) is preferable. A function-separated type (laminated type) photosensitive layer laminated in the order of the layers is more preferred.

  The support used in the electrophotographic photosensitive member of the present invention may be any one as long as it has conductivity, for example, a metal such as aluminum, copper, chromium, nickel, zinc, stainless steel in the form of a drum or a sheet. Examples include a molded product, a laminate of a metal foil such as aluminum or copper on a plastic film, and a product obtained by evaporating aluminum, indium oxide, tin oxide, or the like on a plastic film.

  When the image input is laser light such as LBP, a conductive layer may be provided for the purpose of preventing interference fringes due to scattering or covering scratches on the support. This can be formed by dispersing conductive particles such as carbon black and metal particles in a binder resin.

  5-40 micrometers is preferable and, as for the film thickness of a conductive layer, 10-30 micrometers is more preferable.

  Further, an intermediate layer having an adhesive function may be provided on the support or the conductive layer.

  Examples of the material for the intermediate layer include polyamide, polyvinyl alcohol, polyethylene oxide, ethyl cellulose, casein, polyurethane, and polyether urethane. These are dissolved in an appropriate solvent and applied.

  The thickness of the intermediate layer is preferably 0.05 to 5 μm, more preferably 0.3 to 1 μm.

  The thickness of the charge generation layer is preferably 5 μm or less, more preferably 0.1 to 2 μm.

  As the charge generation material constituting the charge generation layer, commonly known ones can be used. For example, selenium-tellurium, pyrylium, metal phthalocyanine, metal-free phthalocyanine, anthrone, dibenzpyrenequinone, trisazo, cyanine , Pigments such as disazo, monoazo, indigo and quinacrine compounds.

  These pigments are well dispersed by using a homogenizer, ultrasonic dispersion, ball mill, vibration mill, sand mill attritor, roll mill, liquid collision type high-speed disperser, etc. together with binder resin and solvent with a mass of 0.3 to 4 times. A dispersion is obtained. The charge generation layer is obtained by applying this solution and drying.

  The charge transport layer is a charge transport layer coating solution prepared by dissolving a compound having the structure represented by the above formula (A) with the above charge transport material or a compound having the structure represented by the above formula (B) in a solvent. The coating liquid is applied on the charge generation layer and then dried. In addition, the charge transport layer does not necessarily require a binder resin when the charge transport material itself has binding properties, but it binds to the charge transport layer from the viewpoint of mechanical strength and electrophotographic characteristics. It preferably contains a resin. The binder resin is preferably insulating.

  The ratio of the charge transport material to the binder resin (charge transport material / binder resin) in the coating solution is preferably 1/10 to 12/10 in terms of mass ratio, and the charge transport characteristics of the electrophotographic photosensitive member or the charge transport layer 2/10 to 10/10 is more preferable from the standpoint of the strength.

  As the binder resin constituting the charge transport layer, any resin such as a polycarbonate resin, a polyarylate resin, a polyester resin, a polystyrene resin, a polymethacrylate resin, or a polyacrylate resin can be used as long as it can be used for the charge transport layer. However, when the charge transport layer is a surface layer of an electrophotographic photosensitive member, polycarbonate or polyarylate resin is preferable from the viewpoint of resin permeability, film formability, and abrasion resistance. A polyarylate resin is preferred.

  The viscosity average molecular weight (Mv) of the polycarbonate resin is preferably 20000 or more and 80000 or less.

  The divalent organic residue constituting the polycarbonate resin includes a substituted or unsubstituted divalent biphenyl residue, a substituted or unsubstituted divalent bisphenyl residue, a substituted or unsubstituted divalent biphenyl ether residue. Any structure can be used as long as it is a divalent organic residue, such as a group, a substituted or unsubstituted divalent biphenyl thioether residue, a substituted or unsubstituted divalent biphenyl residue, It is preferably a substituted or unsubstituted divalent bisphenyl residue or a substituted or unsubstituted divalent biphenyl ether residue.

  Specific examples of the repeating structural unit of the polycarbonate resin are shown below, but the structure is not particularly limited.

  In addition, in order to improve productivity, it is also possible to use a copolymer resin that uses a different divalent organic residue in the divalent organic residue portion in the polycarbonate resin. In order to efficiently express the effect of mixing, the mixing ratio is preferably 5/95 to 95/5, and more preferably 20/80 to 80/20.

  The weight average molecular weight (Mw) of the polyarylate resin is preferably 50000 or more and 200000 or less, and more preferably 80000 or more and 150,000 or less from the viewpoint of strength, productivity, and the like.

  Regarding the structure of the phthalic acid moiety used in the polyarylate resin, isophthalic acid and terephthalic acid are used. The ratio of terephthalic acid and isophthalic acid in the resin can be arbitrarily selected from isophthalic acid / terephthalic acid = 0/100 to 100/0. From the viewpoint of solubility of the polyarylate resin in the solvent, isophthalic acid / terephthalic acid = It is preferably 20/80 to 80/20. Furthermore, or from the viewpoint of the strength of the resin, isophthalic acid / terephthalic acid = 30/70 to 70/30 is preferable.

  The divalent organic residue part constituting the polyarylate resin is substituted or unsubstituted divalent biphenyl residue, substituted or unsubstituted divalent bisphenyl residue, substituted or unsubstituted divalent biphenyl ether. Any structure can be used as long as it is a divalent organic residue such as a residue, a substituted or unsubstituted divalent biphenylthioether residue, a substituted or unsubstituted divalent biphenyl residue, It is preferably a substituted or unsubstituted divalent bisphenyl residue or a substituted or unsubstituted divalent biphenyl ether residue.

  Specific examples of the repeating structural unit of the polyarylate resin are shown below, but these structures are not particularly limited.

  In order to improve the solubility, it is also possible to use a copolymer resin that uses a different divalent organic residue in the divalent organic residue portion in the polyarylate resin. In order to efficiently express the effect of mixing, the mixing ratio is preferably 5/95 to 95/5, and more preferably 20/80 to 80/20.

  Furthermore, in order to improve productivity, it is also possible to blend a polyarylate resin or polycarbonate resin of another structure with a polycarbonate resin or polyarylate resin. In order to efficiently express the effect of mixing, the mixing ratio is preferably 5/95 to 95/5, and more preferably 20/80 to 80/20.

  When the charge transport layer is a surface layer of an electrophotographic photosensitive member, a lubricant or fine particles may be used as necessary. Examples of the lubricant or fine particles include resin fine particles such as polytetrafluoroethylene fine particles and polystyrene fine particles, metal oxide fine particles such as silica fine particles, alumina fine particles, and tin oxide fine particles, fine particles obtained by subjecting these fine particles to surface treatment, and solid such as zinc stearate. Examples include lubricants, silicones substituted with alkyl groups, aliphatic oils having alkyl fluoride groups, and varnishes.

  The thickness of the charge transport layer is preferably 5 to 40 μm, and preferably 15 to 30 μm.

  Further, as a surface layer of the electrophotographic photoreceptor, a layer for protecting the photosensitive layer, that is, a protective layer may be separately provided on the photosensitive layer.

  The resin used for the protective layer is preferably a high molecular weight thermoplastic resin, thermosetting resin or photocurable resin, and more preferably a high molecular weight polycarbonate resin, polyarylate resin, phenol resin, acrylic resin or epoxy resin. preferable. Further, for the purpose of reducing the residual potential or improving the film strength, conductive particles or a lubricant may be contained.

  The film forming method of the protective layer can be cured by heat, light or electron beam, and may contain a polymerization initiator or an additive compound as necessary.

  In the step of forming each layer of the electrophotographic photoreceptor, examples of the solvent to be used include chlorobenzene, tetrahydrofuran, 1,4-dioxane, toluene, xylene and the like, and a single solvent or a plurality of solvents may be used.

  In addition, as a coating method for forming each layer such as a charge generation layer and a charge transport layer of the electrophotographic photosensitive member, a conventionally known method such as a dip coating method, a spray coating method, a bar coating method, or the like is used. it can.

  Next, an electrophotographic apparatus having a process cartridge having the electrophotographic photosensitive member of the present invention will be described.

  FIG. 4 shows a schematic configuration of an electrophotographic apparatus having a process cartridge having the electrophotographic photosensitive member of the present invention.

  FIG. 4 shows an example of a contact charging type electrophotographic apparatus. This example is a transfer type copying machine or printer.

  Reference numeral 1 denotes an electrophotographic photosensitive member of a drum type. The electrophotographic photosensitive member 1 is rotationally driven in a clockwise direction indicated by an arrow A with a predetermined peripheral speed (process speed).

  A charging roller 2 is a contact charging member as a charging unit. The charging roller 2 rotates following the rotation of the electrophotographic photosensitive member 1 press-fitted to the charging roller, and a DC voltage is applied from the bias power source 2A. The charging roller 2 charges the peripheral surface of the electrophotographic photosensitive member 1 with a predetermined polarity and potential uniformly by a contact charging method.

  The surface of the electrophotographic photosensitive member 1 is irradiated with the exposure light 3 of the target image information by an exposure unit (not shown) such as a document image forming exposure unit or a laser beam scanner. An electrostatic latent image corresponding to the target image information is formed.

  The formed electrostatic latent image is visualized as a transferable particle image (toner image) 5a by regular development or reversal development with the charged particles (toner) 5 of the developing device 4.

  Next, the toner image is fed from the sheet feeding cassette 9 to the sheet feeding roller 10 and the registration roller at the nip (transfer section) between the electrophotographic photosensitive member 1 and the transfer roller 7 serving as a transfer means pressed against the electrophotographic photosensitive member. 11, the transferred particles 5b adhere to the paper 6 fed one by one at a predetermined timing. A bias voltage having a polarity opposite to the charge held in the toner 5 is applied to the transfer roller 7 from a bias power source 7A.

  The sheet 6 that has received the toner image transfer is separated from the surface of the electrophotographic photosensitive member 1 and conveyed to a fixing means (not shown) to undergo a toner image fixing process.

  The surface of the electrophotographic photosensitive member 1 after transfer of the toner image is subjected to removal of adhering contaminants such as residual toner after transfer by a cleaner (cleaning device) 8 to be cleaned and repeatedly used for image formation.

  An example of a contact charging type full-color electrophotographic apparatus having a plurality of electrophotographic photosensitive members, a charging roller and a developing device is shown in FIG. In this full-color electrophotographic apparatus, process cartridges similar to those shown in FIG. 4 containing toners of various colors (black, cyan, magenta, and yellow) are arranged in parallel in a vertical arrangement, sequentially transferred by each transfer means, and finally fixed. This is a color electrophotographic apparatus called a tandem type. 20K, 20C, 20M, and 20Y are each color process cartridge, 21K, 21C, 21M, and 21Y are electrophotographic photosensitive members, 22K, 22C, 22M, and 22Y are charging rollers, 23 is a transfer roller, 24 is a paper conveyance belt, and 25 is a laser. A light source, 26 is toner, 27 is a fixing device, and 28 is a paper feed roller.

  The electrophotographic photoreceptor of the present invention can be used not only in electrophotographic copying machines but also widely in electrophotographic application fields such as laser beam printers, CRT printers, LED printers, liquid crystal printers, and laser plate making.

  Examples of the photosensitive layer of the present invention are shown below, but the present invention is not limited thereto. In the examples, “part” means “part by mass”.

Example 1
SnO ₂ coat treatment 10 parts of barium sulfate, 2 parts of titanium oxide, 6 parts of phenolic resin, 0.001 part of silicone oil was added to 20 parts of a methanol / methoxypropanol = 2/8 mixed solvent to prepare a paint. A conductive layer having a film thickness of 15 μm was formed by coating on an aluminum cylinder 30 mm in diameter × 260.5 mm in length by dip coating and thermosetting at 140 ° C. for 30 minutes.

  Next, a solution obtained by dissolving 3 parts of N-methoxymethylated nylon and 3 parts of copolymer nylon in a mixed solvent of 65 parts of methanol and 30 parts of n-butanol is applied onto this conductive layer by a dip coating method and dried. Thus, an intermediate layer having a film thickness of 0.6 μm was formed.

  Next, 4 parts of hydroxygallium phthalocyanine having strong peaks at diffraction angles 2θ ± 0.2 ° of 7.4 ° and 28.2 ° in the X-ray diffraction spectrum of CuKα, polyvinyl butyral (trade name: ESREC BX-1, 2 parts of Sekisui Chemical Co., Ltd.) and 60 parts of cyclohexanone were dispersed in a sand mill apparatus using glass beads having a diameter of 1 mm for 4 hours, and then 100 parts of ethyl acetate was added to prepare a dispersion for charge generation layer. . This was applied onto the intermediate layer by a dipping method to form a charge generation layer having a thickness of 0.23 μm.

  Next, a copolymer having 5 parts of the compound represented by the above formula (CT-42) as a charge transport material and a repeating structural unit represented by the above formulas (PA-2) and (PA-9) as a binder resin. Polymerized polyarylate resin (weight average molecular weight (Mw) = 15000, mass ratio of terephthalic acid to isophthalic acid in resin: terephthalic acid / isophthalic acid = 50/50, copolymerization ratio = (PA-2) / (PA-9 ) = 7/3) and 2,6-di-tert-butyl-p-cresol represented by the above formula (AO-1) as a compound having the structure represented by the above formula (A) (product) (Name: BHT, manufactured by Tokyo Chemical Industry Co., Ltd.) 0.50 part was dissolved in 100 parts of monochlorobenzene to prepare a coating solution for charge transport layer. This was applied onto the charge generation layer by a dipping method and dried at 120 ° C. for 1 hour to form a charge transport layer having a thickness of 17 μm.

  Thus, the electrophotographic photosensitive member of the present invention was produced.

  Next, a method for evaluating an electrophotographic photoreceptor will be described.

The evaluation apparatus used was LBP-2510 manufactured by Canon Inc. (primary charging: contact charging method, process speed: 94.2 mm / sec) modified so that the charging potential of the electrophotographic photosensitive member can be adjusted. Evaluation was performed in a high temperature and high humidity environment (30 ° C., 80% RH). The dark part potential (Vd) of the produced electrophotographic photosensitive member, the light part potential (Vl) light-attenuated from the dark part potential Vd by irradiation with light, and the dark part potential (Vd ₂₀₀₀ ) from the initial stage when 2000 sheets are repeatedly used. Evaluation of the variation (Vd ₂₀₀₀ −Vd = ΔVd) and the variation (Vl ₂₀₀₀ −Vl = ΔVl) from the initial stage of the bright portion potential (Vl ₂₀₀₀ ) when 2000 sheets are repeatedly used is based on the image of the light source of the apparatus. The exposure amount is set so that the amount of light on the surface of the electrophotographic photosensitive member is 0.3 μJ / cm ^2, and the dark portion potential (Vd) of the non-exposed portion of the electrophotographic photosensitive member is Vd = −500V. This was done by continuously outputting 2000 sheets of A4 size plain paper and measuring the surface potential before and after that. The measurement of the surface potential of the electrophotographic photosensitive member was performed at the position of the developing device by exchanging the jig and the developing device fixed so that the potential measuring probe was positioned at a position 130 mm from the end of the electrophotographic photosensitive member. . The results are shown in Table 1.

  As for the evaluation method of the optical memory of the electrophotographic photosensitive member, a black film with a 1 cm × 5 cm hole is attached so that the hole is 130 mm from the end of the electrophotographic photosensitive member, and is shielded from light. The position of the halogen lamp is adjusted so that the exposure amount of 1500 Lux is on the surface of the electrophotographic photosensitive member, the white light of 1500 Lux is applied to the electrophotographic photosensitive member for 5 minutes, the black film is removed, and a light shielding portion ( Vd (light-shielding part)) and non-light-shielding part (Vd (non-light-shielding part)) dark part potential difference (Vd (non-light-shielding part) −Vd (light-shielding part) = optical memory) was measured. The results are shown in Table 1.

  Also, 1000 images are output in an intermittent mode in which A4 size plain paper is stopped once for each image output. After 1000 images are output, the amount of scraping from the initial stage of the electrophotographic photosensitive member is evaluated. went. The film thickness at that time was measured with a film thickness measuring device, Fisher MMS eddy current method probe EAW3.3, manufactured by Fischer. The results are shown in Table 1.

(Examples 2 to 19)
A compound having the structure represented by the above formula (A) shown in the “addition compound” column of Table 1 as an additive compound or a compound shown in the “charge transport material” column of Table 1 as a charge transport material or the above formula An electrophotographic photoreceptor was prepared in the same manner as in Example 1 except that the compound having the structure represented by (B) was used, and the same evaluation was performed. The results are shown in Table 1.

  The compound represented by the above formula (AO-2) used as the additive compound is a product name: IRGANOX 1330, manufactured by Ciba Specialty Chemicals Co., Ltd., and the compound represented by the above formula (AO-3) is a product Name: IRGANOX 1035, manufactured by Ciba Specialty Chemicals Co., Ltd., the compound represented by the above formula (AO-4) is trade name: IRGANOX 259, manufactured by Ciba Specialty Chemicals Co., Ltd., the above formula (AO-5) ) Are trade names: IRGANOX 1010, manufactured by Ciba Specialty Chemicals Co., Ltd., and the compounds represented by the above formula (AO-6) are trade names: IRGANOX 565, Ciba Specialty Chemicals Co., Ltd. The compound represented by the above formula (AO-7) is trade name: SANOL LS-2626, Sankyo The compound represented by the above formula (AO-8) manufactured by IFTEC Co., Ltd. is a trade name: TINUVIN 144, manufactured by Ciba Specialty Chemicals Co., Ltd., the compound represented by the above formula (AO-9) is a trade name : TINUVIN 765, manufactured by Ciba Specialty Chemicals Co., Ltd., the compound represented by the above formula (AO-10) is a product name: TINUVIN 123, manufactured by Ciba Specialty Chemicals Co., Ltd., the above formula (AO-11) Is a product name: TINUVIN 622LD, manufactured by Ciba Specialty Chemicals Co., Ltd.

(Example 20)
An electrophotographic photoreceptor was prepared in the same manner as in Example 19 except that the content of the additive compound was changed from 0.50 part to 0.25 part, and the same evaluation was performed. The results are shown in Table 1.

(Example 21)
An electrophotographic photosensitive member was prepared in the same manner as in Example 19 except that the content of the additive compound was changed from 0.50 part to 0.75 part, and the same evaluation was performed. The results are shown in Table 1.

(Example 22)
An electrophotographic photoreceptor was prepared in the same manner as in Example 19 except that the content of the additive compound was changed from 0.50 part to 1.00 part, and the same evaluation was performed. The results are shown in Table 1.

(Examples 23 to 34)
A compound having the structure represented by the above formula (A) shown in the “addition compound” column of Table 1 as an additive compound or a compound shown in the “charge transport material” column of Table 1 as a charge transport material or the above formula An electrophotographic photoreceptor was prepared in the same manner as in Example 1 except that the compound having the structure represented by (B) was used, and the same evaluation was performed. The results are shown in Table 1.

(Examples 35-37)
5 parts of the compound represented by the above formula (CT-17) as the charge transport material, and the compound having the structure represented by the above formula (A) shown in the column of “addition compound” of Table 1 as the additive compound, or the above 0.5 part of a compound having a structure represented by the formula (B) is used, and a polyarylate resin having a repeating structural unit represented by the above formula (PA-2) as a binder resin (weight average molecular weight (Mw) = An electrophotographic photosensitive member was prepared and evaluated in the same manner as in Example 1 except that 120,000 was used, and the mass ratio of terephthalic acid to isophthalic acid in the resin: terephthalic acid / isophthalic acid = 50/50). The results are shown in Table 1.

(Examples 38 to 40)
Examples 35 to 37 except that a polycarbonate resin having a repeating structural unit represented by the above formula (PC-5) (trade name: Iupilon Z-400, manufactured by Mitsubishi Engineering Plastics Co., Ltd.) was used as a binder resin. An electrophotographic photosensitive member was prepared in the same manner as described above, and the same evaluation was performed. The results are shown in Table 1.

(Examples 41 to 43)
Polyarylate resin (weight average molecular weight (Mw)) having 5 parts of the compound represented by the above formula (CT-10) as a charge transport material and the repeating structural unit represented by the above formula (PA-10) as a binder resin = 130,000, and the electrophotographic photosensitive member was prepared in the same manner as in Example 1 except that the mass ratio of terephthalic acid and isophthalic acid in the resin: terephthalic acid / isophthalic acid = 70/30) was used. . The results are shown in Table 1.

(Examples 44 to 50)
Example 1 except that 5 parts of the compound represented by the above formula (CT-17) as a charge transport material and the additive compound shown in Table 2 were mixed and the total mass of the additive compound was 0.5 parts. Similarly, an electrophotographic photosensitive member was produced and evaluated in the same manner. The results are shown in Table 2. Here, “mixing ratio of additive compound” in Table 2 means that “additive compound A / mass part of additive compound B” when additive compound A and additive compound B are mixed and used. Show. For example, in Example 44, 0.45 parts by mass of the additive compound represented by the above formula (AO-2) and 0.05 part by mass of the additive compound represented by the above formula (AO-15) were mixed and used. Indicates that

(Examples 51 to 61)
Example 1 was used except that the charge transport material shown in the column “Charge transport material” in Table 3 and the additive compound shown in the column “Addition compound” in Table 3 were used as the charge transport material. An electrophotographic photoreceptor was prepared and evaluated in the same manner. The results are shown in Table 3.

(Examples 62 to 72)
As in Example 1, except that the charge transport material shown in the column “Charge transport material” in Table 4 and the additive compound shown in the column “Additive compound” in Table 4 were used as the charge transport material. An electrophotographic photoreceptor was prepared and evaluated in the same manner. The results are shown in Table 4.

(Examples 73 to 83)
Example 1 was used except that the charge transport material shown in the column “Charge transport material” in Table 5 and the additive compound shown in the column “Additive compound” in Table 5 were used as the charge transport material. An electrophotographic photoreceptor was prepared and evaluated in the same manner. The results are shown in Table 5.

(Examples 84 to 94)
Example 1 was used except that the charge transport material shown in the column “Charge transport material” in Table 6 and the additive compound shown in the column “Additive compound” in Table 6 were used as the charge transport material. An electrophotographic photoreceptor was prepared and evaluated in the same manner. The results are shown in Table 6.

(Comparative Examples 1-10)
As in Example 1, except that the charge transport material shown in the column “Charge transport material” in Table 7 and the additive compound shown in the column “Additive compound” in Table 7 were used as the charge transport material. An electrophotographic photoreceptor was prepared and evaluated in the same manner. The results are shown in Table 7. In addition, the additive compounds (AO-12) to (AO-20) shown in the column of “additive compound” in Table 7 are compounds having the following structure.

  In the above formulas (AO-12), (AO-15), and (AO-17), tBu represents a tertiary butyl group, and n in the above formula (AO-19) represents the number of repeating structural units.

The compound represented by the above formula (AO-12) used as the additive compound is a product name: IRGANOX 245, manufactured by Ciba Specialty Chemicals Co., Ltd., and the compound represented by the above formula (AO-13) is a product Name: TINUVIN 770DF, manufactured by Ciba Specialty Chemicals Co., Ltd., the compound represented by the above formula (AO-14) is a product name: TINUVIN 234, manufactured by Ciba Specialty Chemicals Co., Ltd., the above formula (AO-15) ) Is a product name: IRGAFOS 168, manufactured by Ciba Specialty Chemicals Co., Ltd., and a compound represented by the above formula (AO-16) is a product name: Sumilizer GS, manufactured by Sumitomo Chemical Co., Ltd., The compound represented by the above formula (AO-17) is trade name: Antage W500, manufactured by Kawaguchi Chemical Industry Co., Ltd. The compound represented by the above formula (AO-18) is trade name: IRGANOX 1520, manufactured by Ciba Specialty Chemicals Co., Ltd., and the compound represented by the above formula (AO-19) is trade name: CHIMASSORB 944LD, Ciba The compound represented by the above formula (AO-20) manufactured by Specialty Chemicals Co., Ltd. is a trade name: Sumilizer TPS, manufactured by Sumitomo Chemical Co., Ltd.
Moreover, the comparative example described as "no addition" in the column of "addition compound" of Table 7 shows that the additive compound is not contained.

(Comparative Example 11)
An electrophotographic photosensitive member was prepared in the same manner as in Example 19 except that the content of the additive compound was changed from 0.50 part to 0.20 part, and the same evaluation was performed. The results are shown in Table 7.

(Comparative Example 12)
An electrophotographic photoreceptor was prepared in the same manner as in Example 19 except that the content of the additive compound was changed from 0.50 part to 1.25 parts, and the same evaluation was performed. The results are shown in Table 7.

(Comparative Examples 13-24)
As in Example 1, except that the charge transport material shown in the column “Charge transport material” in Table 7 and the additive compound shown in the column “Additive compound” in Table 7 were used as the charge transport material. An electrophotographic photoreceptor was prepared and evaluated in the same manner. The results are shown in Table 7.

(Comparative Example 25)
As a charge transport material, 15 parts of a polymer type polymer charge transport material having a repeating structural unit represented by the following formula (PCT-1) was dissolved in 100 parts of chlorobenzene to obtain a coating solution for a charge transport layer. An electrophotographic photosensitive member was produced in the same manner as in Example 1 except that this charge transport layer coating solution was used, and the same evaluation as in Example 1 was performed. The results are shown in Table 7. Measurement by ordinary gel permeation chromatography (GPC) (column used: Showa Denko KF-802, developing solvent: methanol / tetrahydrofuran = 7/3, detector: RI detector, sample molecular weight is polystyrene In the determination by the conversion method), the weight average molecular weight (Mw) of the compound represented by the following formula (PCT-1) was 2000.

(Comparative Examples 26-36)
15 parts of a polymer type polymeric charge transport material having a repeating structural unit represented by the above formula (PCT-1) as a charge transport material, and the additive compound shown in the “addition compound” column of Table 7 as an additive compound 0. An electrophotographic photosensitive member was produced in the same manner as in Example 1 except that 3 parts were used, and the same evaluation was performed. The results are shown in Table 7.

(Comparative Example 37)
As the charge transport material, a compound represented by the following formula (PCT-2) synthesized by a polymerization reaction described in Patent Document 2 was used. The compound represented by the following formula (PCT-2) was measured by ordinary gel permeation chromatography (GPC) (column used: KF-802 manufactured by Showa Denko KK, developing solvent: methanol / tetrahydrofuran = 7/3, detector) : The number of repetitions n = 4: n = 5: n = 6: n = 7: n = 8 is 7: 23: 50: 17 depending on the peak area ratio of: RI detector, molecular weight of sample determined by polystyrene conversion method) : Charge transport material mixed in a ratio of 3. Moreover, in the measurement by GPC, the weight average molecular weight (Mw) of the compound shown by a following formula (PCT-2) was 1700. An electrophotographic photosensitive member was produced in the same manner as in Example 1 except that 5 parts of the compound represented by the following formula (PCT-2) was used, and the same evaluation was performed. The results are shown in Table 7.

(Comparative Examples 38-48)
5 parts of a polymer type polymer charge transporting material having a repeating structural unit represented by the following formula (PCT-2) as a charge transporting material, and an additive compound 0. An electrophotographic photosensitive member was produced in the same manner as in Example 1 except that 5 parts were used, and the same evaluation was performed. The results are shown in Table 7.

(Comparative Example 49)
An electrophotographic photosensitive member was produced in the same manner as in Example 1 except that 5 parts of the compound represented by the following formula (SCT-1) was used as the charge transport material, and the same evaluation was performed. The results are shown in Table 7.

(Comparative Example 50)
An electrophotographic photoreceptor was prepared in the same manner as in Example 1 except that 5 parts of the compound represented by the above formula (SCT-1) was used as the charge transport material and 0.5 parts of (AO-11) was used as the additive compound. The same evaluation was performed. The results are shown in Table 7.

  Comparing Examples and Comparative Examples, in the photosensitive layer using the specific charge transporting material and the specific additive compound in the present invention in combination, compared to the case of using the photosensitive layer using the other charge transporting material and the additive compound in combination, The sensitivity at the same exposure amount is good, the fluctuation of the bright part potential before and after repeated use is reduced and the potential stability is improved, and the amount of wear of the charge transport layer is small even during long-term repeated use. small. The reason why ΔVl is a negative value in the table is that the amount of shaving is large. By using the electrophotographic photosensitive member of the present invention, it is considered possible to provide a stable image over a long period of time without any change in density between initial use and repeated use.

It is a MALDI-TOF-MASS spectrum of exemplary compound (CT-10) of this invention. It is a MALDI-TOF-MASS spectrum of exemplary compound (CT-17) of this invention. It is a MALDI-TOF-MASS spectrum of exemplary compound (CT-39) of this invention. FIG. 3 is a diagram illustrating an example of a contact charging type process cartridge and an electrophotographic apparatus. 1 is a diagram illustrating an example of a full-color contact charging type electrophotographic apparatus. FIG. The process cartridge shown in FIG. 4 is a system in which yellow, magenta, cyan, and black are arranged in the vertical order from the bottom in a tiedem manner.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Electrophotographic photoreceptor 2 Charging roller 2A Bias power supply 3 Exposure light 4 Developer 5 Charged particle (toner)
5a Transferable particle image (toner image)
5b Particles to be transferred 6 Paper 7 Transfer roller 7A Bias power supply 8 Cleaner (cleaning device)
DESCRIPTION OF SYMBOLS 9 Paper feed cassette 10 Paper feed roller 11 Registration roller 20K, 20C, 20M, 20Y Each color process cartridge 21K, 21C, 21M, 21Y Electrophotographic photosensitive member 22K, 22C, 22M, 22Y Charging roller 23 Transfer roller 24 Paper conveyance belt 25 Laser Light source 26 Toner 27 Fixing device 28 Paper feed roller

Claims (11)

Has a support and a photosensitive layer formed on the support, an electrophotographic photosensitive member the photosensitive layer contains a charge transport material and additive compound,
The following formula (1) with respect to the total mass of the charge transport material contained in the photosensitive layer:

(In formula (1) , Ar _{101 to} Ar ₁₀₈ each independently represents a substituted or unsubstituted monovalent aromatic hydrocarbon ring group, or a substituted or unsubstituted monovalent aromatic heterocyclic group. Z _{11 to} Z ₁₅ each independently represents a substituted or unsubstituted divalent aromatic hydrocarbon ring group or a substituted or unsubstituted divalent aromatic heterocyclic group.
In having a structure shown, and the proportion of the molecular weight of the charge transporting substance is 1500 to 4,000 is 1 00% by weight and,
At least one additive compound contained in the photosensitive layer, the following equation (1-1)

(In the formula (1-1) , tBu is a tertiary butyl group, R ₁ is a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted hydroxyl group, a substituted or unsubstituted ester group, A substituted or unsubstituted amino group or a substituted or unsubstituted cycloalkyl group is shown.)
Or a compound having a structure represented by the following formula (1-2)

(In Formula (1-2) , R ₂ and R ₃ are each independently a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted hydroxyl group, a substituted or unsubstituted ester group. Represents a substituted or unsubstituted amino group or a substituted or unsubstituted cycloalkyl group.)
And a compound having a structure represented by :
The mass (X _1-1 ) of the compound having the structure represented by the above formula (1-1) contained in the photosensitive layer and the mass of the compound having the structure represented by the above formula (1-2) (X ₁₋ sum of the mass of _{2) (in X} 1-1 ₊ X _1-2), the ratio of the values to the total weight of the charge transport material included in the photosensitive layer _{(Y 1) ((X 1-1} + X 1-2) / Y ₁ ) is 0.05 or more and 0.20 or less. Has a support and a photosensitive layer formed on the support, an electrophotographic photosensitive member the photosensitive layer contains a charge transport material and additive compound,
With respect to the total mass of the charge transport material contained in the photosensitive layer, the following formula (2)

(In the formula (2) , Ar _{201 to} Ar ₂₀₉ each independently represent a substituted or unsubstituted monovalent aromatic hydrocarbon ring group or a substituted or unsubstituted monovalent aromatic heterocyclic group. Z _{21 to} Z ₂₆ each independently represent a substituted or unsubstituted divalent aromatic hydrocarbon ring group or a substituted or unsubstituted divalent aromatic heterocyclic group.
In having a structure shown, and the proportion of the molecular weight of the charge transporting substance is 1500 to 4,000 is 1 00% by weight and,
At least one additive compound contained in the photosensitive layer, the following equation (2-1)

(In the formula (2-1) , tBu is a tertiary butyl group, R ₄ is a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted hydroxyl group, a substituted or unsubstituted ester group, A substituted or unsubstituted amino group or a substituted or unsubstituted cycloalkyl group is shown.)
Or a compound having a structure represented by the following formula (2-2)

(In Formula (2-2) , R ₅ and R ₆ are each independently a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted hydroxyl group, a substituted or unsubstituted ester group. Represents a substituted or unsubstituted amino group or a substituted or unsubstituted cycloalkyl group.)
And a compound having a structure represented by :
The mass (X _2-1 ) of the compound having the structure represented by the above formula (2-1) and the mass of the compound having the structure represented by the above formula (2-2) contained in the photosensitive layer (X _{2− 2} ) The value of the ratio of the total mass (X _2-1 + X _2-2 ) to the total mass (Y ₂ ) of the charge transport material contained in the photosensitive layer ((X _2-1 + X _2-2 ) / Y ₂ ) is 0.05 or more and 0.20 or less. Has a support and a photosensitive layer formed on the support, an electrophotographic photosensitive member the photosensitive layer contains a charge transport material and additive compound,
With respect to the total mass of the charge transport material contained in the photosensitive layer, the following formula (3)

(In Formula (3) , Ar _{301 to} Ar ₃₁₀ each independently represent a substituted or unsubstituted monovalent aromatic hydrocarbon ring group or a substituted or unsubstituted monovalent aromatic heterocyclic group. Z _{31 to} Z ₃₇ each independently represent a substituted or unsubstituted divalent aromatic hydrocarbon ring group or a substituted or unsubstituted divalent aromatic heterocyclic group.
In having a structure shown, and the proportion of the molecular weight of the charge transporting substance is 1500 to 4,000 is 1 00% by weight and,
At least one additive compound contained in the photosensitive layer, the following equation (3-1)

(In the formula (3-1) , tBu is a tertiary butyl group, R ₇ is a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted hydroxyl group, a substituted or unsubstituted ester group, A substituted or unsubstituted amino group or a substituted or unsubstituted cycloalkyl group is shown.)
Or a compound having a structure represented by the following formula (3-2)

(In Formula (3-2) , R ₈ and R ₉ are each independently a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted hydroxyl group, a substituted or unsubstituted ester group. Represents a substituted or unsubstituted amino group or a substituted or unsubstituted cycloalkyl group.)
And a compound having a structure represented by :
The mass (X _3-1 ) of the compound having the structure represented by the above formula (3-1) and the mass of the compound having the structure represented by the above formula (3-2) (X _{3 −3} ) contained in the photosensitive layer. ₂ ) the value of the ratio of the total mass (X _3-1 + X _3-2 ) to the total mass (Y ₃ ) of the charge transport material contained in the photosensitive layer ((X _3-1 + X _3-2 ) / Y ₃ ) is 0.05 or more and 0.20 or less. Has a support and a photosensitive layer formed on the support, an electrophotographic photosensitive member the photosensitive layer contains a charge transport material and additive compound,
With respect to the total mass of the charge transport material contained in the photosensitive layer, the following formula (4)

(In formula (4) , Ar _{401 to} Ar ₄₁₁ each independently represent a substituted or unsubstituted monovalent aromatic hydrocarbon ring group or a substituted or unsubstituted monovalent aromatic heterocyclic group. Z _{41 to} Z ₄₈ each independently represent a substituted or unsubstituted divalent aromatic hydrocarbon ring group or a substituted or unsubstituted divalent aromatic heterocyclic group.
In having a structure shown, and the proportion of the molecular weight of the charge transporting substance is 1500 to 4,000 is 1 00% by weight and,
At least one additive compound contained in the photosensitive layer, the following equation (4-1)

(In the formula (4-1) , tBu is a tertiary butyl group, R ₁₀ is a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted hydroxyl group, a substituted or unsubstituted ester group, A substituted or unsubstituted amino group or a substituted or unsubstituted cycloalkyl group is shown.)
Or a compound having a structure represented by the following formula (4-2)

(In Formula (4-2) , R ₁₁ and R ₁₂ are each independently a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted hydroxyl group, a substituted or unsubstituted ester group. Represents a substituted or unsubstituted amino group or a substituted or unsubstituted cycloalkyl group.)
And a compound having a structure represented by :
The mass (X _4-1 ) of the compound having the structure represented by the above formula (4-1) contained in the photosensitive layer and the mass of the compound having the structure represented by the above formula (4-2) (X _{4− 2} ) The value of the ratio of the total mass (X _4-1 + X _4-2 ) to the total mass (Y ₄ ) of the charge transport material contained in the photosensitive layer ((X _4-1 + X _4-2 ) / Y ₄ ) is 0.05 or more and 0.20 or less. Has a support and a photosensitive layer formed on the support, an electrophotographic photosensitive member the photosensitive layer contains a charge transport material and additive compound,
The following formula (5) with respect to the total mass of the charge transport material contained in the photosensitive layer:

(In formula (5) , Ar _{501 to} Ar ₅₁₂ each independently represent a substituted or unsubstituted monovalent aromatic hydrocarbon ring group, or a substituted or unsubstituted monovalent aromatic heterocyclic group. And Z _{51 to} Z ₅₉ each independently represent a substituted or unsubstituted divalent aromatic hydrocarbon ring group or a substituted or unsubstituted divalent aromatic heterocyclic group.
In having a structure shown, and the proportion of the molecular weight of the charge transporting substance is 1500 to 4,000 is 1 00% by weight and,
At least one additive compound contained in the photosensitive layer, the following equation (5-1)

(In the formula (5-1) , tBu is a tertiary butyl group, R ₁₃ is a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted hydroxyl group, a substituted or unsubstituted ester group, A substituted or unsubstituted amino group or a substituted or unsubstituted cycloalkyl group is shown.)
Or a compound having a structure represented by the following formula (5-2)

(In Formula (5-2) , R ₁₄ and R ₁₅ are each independently a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted hydroxyl group, a substituted or unsubstituted ester group. Represents a substituted or unsubstituted amino group or a substituted or unsubstituted cycloalkyl group.)
And a compound having a structure represented by :
The mass (X _5-1 ) of the compound having the structure represented by the above formula (5-1) and the mass of the compound having the structure represented by the above formula (5-2) contained in the photosensitive layer (X _{5− 2} ) The value of the ratio of the total mass (X _5-1 + X _5-2 ) to the total mass (Y ₅ ) of the charge transport material contained in the photosensitive layer ((X _5-1 + X _5-2 ) / Y ₅ ) is 0.05 or more and 0.20 or less. At least one of the additive compounds contained in the photosensitive layer is represented by the following formulas (AO-1) to (AO-11)

(In formulas (AO-1) to (AO-8), tBu represents a tertiary butyl group, and in formula (AO-11), n represents the number of repeating structural units.)
The electrophotographic photosensitive member according to any one of the compounds der Ru請 Motomeko 1-5 having the structure represented by any of. Among Z _{11 to} Z ₁₅ in the formula (1), at least one is a substituted or unsubstituted dibenzofuranylene group or a substituted or unsubstituted dibenzothiophenylene group, and the other Z _{11 to} Z ₁₅ Is a substituted or unsubstituted biphenylene group, or
At least one of Z _{21 to} Z ₂₆ in the formula (2) is a substituted or unsubstituted dibenzofuranylene group or a substituted or unsubstituted dibenzothiophenylene group, and the other Z _{21 to} Z ₂₆ Is a substituted or unsubstituted biphenylene group, or
Among Z _{31 to} Z ₃₇ in the formula (3), at least one is a substituted or unsubstituted dibenzofuranylene group or a substituted or unsubstituted dibenzothiophenylene group, and the other Z _{31 to} Z ₃₇ Is a substituted or unsubstituted biphenylene group, or
Among Z _{41 to} Z ₄₈ in the formula (4), at least one is a substituted or unsubstituted dibenzofuranylene group or a substituted or unsubstituted dibenzothiophenylene group, and the other Z _{41 to} Z ₄₈ Is a substituted or unsubstituted biphenylene group, or
Among Z _{51 to} Z ₅₉ in the formula (5), at least one is a substituted or unsubstituted dibenzofuranylene group or a substituted or unsubstituted dibenzothiophenylene group, and the other Z _{51 to} Z ₅₉ Ru biphenylene group der of but a substituted or unsubstituted
The electrophotographic photosensitive member according to any one of 請 Motomeko 1-6. Has a structure represented by any one of the previous following formula (1) to (5), and a charge transport material molecular weight of 1500 or more 4000 or less, Ru charge transport material der synthesized by sequential synthesis method according Item 8. The electrophotographic photosensitive member according to any one of Items 1 to 7 . The electrophotographic photosensitive member according to any one of 請 Motomeko 1-8 you containing the photosensitive layer is a polyarylate resin. An electrophotographic photosensitive member according to any one of claims 1 to 9 charging means, and at least one means selected from the group consisting of the developing means and cleaning means integrally supported, detachably attached to an electrophotographic apparatus main body Process cartridge characterized by being. The electrophotographic photosensitive member according to any one of claims 1 to 9, a charging means, an exposure means, the electrophotographic apparatus, characterized in that it comprises a developing means and a transfer means.

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