JP5057907B2 - Electrophotographic apparatus and process cartridge - Google Patents

Description

  The present invention relates to an electrophotographic apparatus and a process cartridge capable of obtaining an excellent image.

In general, a corona charging method or a contact charging method has been used as a charging method in electrophotography.
Corona charging methods include a corotron method and a scorotron method with a grid, and a direct current or a direct current voltage superimposed on an alternating current is applied to a tungsten or nickel charge wire placed in the center of a housing shielded by a metal plate. In this method, corona discharge is caused to charge the photosensitive member. However, in this method, ozone, nitrogen oxide, or the like is generated in order to apply a high voltage to the charge wire. This product is known to have an adverse effect not only on environmental aspects but also on the photoreceptor and durability and image characteristics.

In recent years, instead of this method, a contact charging method has been put into practical use for the purpose of low ozone and low power. The contact charging method is a method of applying a direct current or a direct current voltage on which an alternating current is applied to a charging member having a resistance of about 10 ² to 10 ¹⁰ Ω · cm, and applying pressure to the photosensitive member to apply a charge. . Since this charging method is performed by discharging from the charging member to the member to be charged in accordance with Paschen's law, charging is started by applying a voltage equal to or higher than a certain threshold voltage. In this contact charging method, compared with the corona charging method, the voltage applied to the charging member is low, but since discharge is accompanied, a small amount of ozone and nitrogen oxides are generated.

  Therefore, as a new charging method, Patent Document 1 discloses a charging method by direct injection of charges into a photoconductor. This charging method is a method in which a charge injection layer is provided on the surface of a photoconductor, a voltage is applied to a contact conductive member such as a charging roller, a charging brush, a charging magnetic brush, etc., and injection charging is performed by contacting the charge. In this charging method, almost one-to-one charging is possible with respect to the applied voltage with almost no discharge phenomenon. Therefore, compared with the conventional contact charging method, the amount of ozone and NOx generated is very small. It is an excellent charging method with low power.

As the charge injection layer provided on the photosensitive member for performing the charge injection charging, a resin in which a metal oxide such as tin oxide is dispersed in a resin is used. Charge injection layers composed of these metal oxides and resins tend to cause uneven charging on the surface of the photoconductor due to uneven dispersion of the metal oxide, and in addition, contact at the contact charging part, toner developing part, and transfer part. It became clear that the durability by was inferior.
In addition, in the electrophotographic photosensitive member that has been attempted to be used for injection charging, the charge injection property from the charging member to the surface of the photosensitive member is not sufficient. It was necessary to secure a sufficient contact area and to increase the contact pressure and take a sufficiently long time for charging.

However, when the contact pressure between the charging member and the surface of the photosensitive member is increased in this way, scratches are generated on the surface of the photosensitive member due to friction between the charging member and the surface of the photosensitive member during repeated use, and the surface is scraped. As a result, the durable life of the photoreceptor has been determined.
In contrast, the photoreceptor described in Patent Document 2 disperses conductive particles in a photocurable acrylic monomer having three or more acryloyl groups, which are relatively high polar groups, in one molecule. By using a surface layer formed by coating and photocuring on the photosensitive layer of the photoreceptor, both the film strength and the dispersibility of the conductive fine particles are improved.

Although the dispersibility of conductive fine particles and film strength have been improved by the above-mentioned techniques, increasing the amount of functional groups with the aim of high wear resistance increases the film strength but increases the shrinkage ratio during curing, so In the body, it causes cracks in the underlying photosensitive layer, so that it was difficult to form a cured surface layer having good dispersibility of conductive fine particles, sufficient film strength, and low shrinkage. .
JP-A-6-003921 JP-A-6-035220

  An object of the present invention is to provide an electrophotographic apparatus and a process cartridge that can perform good injection charging, obtain an excellent image, and have a sufficiently long durable life of a photoreceptor.

As a result of intensive studies, the present inventors have found that the above object can be achieved by the following (1) to (9), and have completed the present invention.
(1) In an electrophotographic apparatus having an electrophotographic photosensitive member, a charging member that is placed in contact with the electrophotographic photosensitive member and charges the electrophotographic photosensitive member by applying a voltage, an exposure unit, a developing unit, and a transfer unit The electrophotographic photosensitive member has a photosensitive layer that is not radically cured, and a surface layer containing a radical curable composition and conductive fine particles, and is represented by at least the following general formula (A) in the radical curable composition. An electrophotographic apparatus comprising: a structural unit, wherein the charge is injection charge.
(Expressed in the _{formula, R 5, R 6, R} 7 and R ₈ are each a hydrogen atom, a linear or branched or cyclic alkyl group having 1 to 6 carbon atoms, an allyl group, a halogen atom, an aryl group, R ₉ And R ₁₀ represents a hydrogen atom, a methyl group, or an ethyl group, except that all of R _{5 to} R ₈ are hydrogen atoms, and the sum of the carbon number of R _{9 and} the carbon number of R ₁₀ is 0 to 2. is there.)

(2) The surface layer of the electrophotographic photosensitive member is coated with a coating solution containing at least conductive fine particles and a radical polymerizable compound represented by the following general formula (B) on the surface of the photosensitive layer. The electrophotographic apparatus according to (1), wherein the electrophotographic apparatus is formed by radically curing the radically polymerizable compound in the coating film after the formation.
(In the formula, R ₁ and R ₂ each represent a linear or branched alkylene group having 1 to 6 carbon atoms, 1-ketohexylene group, R ₃ and R ₄ represent a hydrogen atom or a methyl group, R ₅ , R ₆ , R ₇ and R ₈ each represent a hydrogen atom, a linear, branched or cyclic alkyl group having 1 to 6 carbon atoms, an allyl group, a halogen atom or an aryl group, and R ₉ and R ₁₀ are hydrogen atoms. Represents an atom, a methyl group, or an ethyl group, and n to m each represents an integer of 0 to 4, except when all of R _{5 to} R ₈ are hydrogen atoms, the number of carbons of R _{9 and} the carbon number of R ₁₀ The sum of the numbers is 0-2.)

(3) The surface layer of the electrophotographic photoreceptor is coated with a coating solution containing at least conductive fine particles and a radical polymerizable compound represented by the following general formula (C) on the surface of the photosensitive layer. The electrophotographic apparatus according to (1), wherein the electrophotographic apparatus is formed by radically curing the radically polymerizable compound in the coating film after the formation.
(In the formula, R ₁₁ , R ₁₂ , R ₁₃ and R ₁₄ each represent a hydrogen atom or a methyl group, and R ₅ , R ₆ , R ₇ and R ₈ are each a hydrogen atom and a straight chain having 1 to 6 carbon atoms. Or a branched or cyclic alkyl group, an allyl group, a halogen atom, or an aryl group, and R ₉ and R ₁₀ represent a hydrogen atom, a methyl group, or an ethyl group, provided that all of R _{5 to} R ₈ are hydrogen atoms. (The sum of the carbon number of R _{9 and} the carbon number of R ₁₀ is 0 to 2.)

(4) The surface layer of the electrophotographic photoreceptor is coated with a coating solution containing at least conductive fine particles and a radical polymerizable compound represented by the following general formula (D) on the surface of the photosensitive layer. The electrophotographic apparatus according to (1), wherein the electrophotographic apparatus is formed by radically curing the radically polymerizable compound in the coating film after the formation.
(Wherein R ₂₁ and R ₂₂ each represent a hydrogen atom or a methyl group, and R ₅ , R ₆ , R ₇ and R ₈ are each a hydrogen atom, a linear, branched or cyclic alkyl having 1 to 6 carbon atoms. A group, an allyl group, a halogen atom, and an aryl group, R ₉ and R ₁₀ represent a hydrogen atom, a methyl group, and an ethyl group, and n represents an integer of 1 to 50, provided that all of R _{5 to} R ₈ are hydrogen. (When it is an atom, the sum of the carbon number of R _{9 and} the carbon number of R ₁₀ is 0 to 2.)

(5) surface layer of the electrophotographic photosensitive member, at least conductive fine particles and the following general formula (B), (C), and any of the radical polymerizable compound represented by (D), further radical polymerizable functional group A coating solution containing a monomer having 3 or more is applied to the surface of the photosensitive layer to form a coating film, and the monomer having 3 or more radically polymerizable compounds and radically polymerizable functional groups in the coating film is radically cured. The electrophotographic apparatus according to any one of (1) to (4), wherein the electrophotographic apparatus is formed.
(In the formula, R ₁ and R ₂ each represent a linear or branched alkylene group having 1 to 6 carbon atoms, 1-ketohexylene group, R ₃ and R ₄ represent a hydrogen atom or a methyl group, R ₅ , R ₆ , R ₇ and R ₈ each represent a hydrogen atom, a linear, branched or cyclic alkyl group having 1 to 6 carbon atoms, an allyl group, a halogen atom or an aryl group, and R ₉ and R ₁₀ are hydrogen atoms. atom, a methyl group, an ethyl group, n to m represents an integer of 0 to 4. However carbon carbon number and R ₁₀ of the .R ₉ except when all R ₅ to R ₈ is a hydrogen atom The sum of the numbers is 0-2.)
(In the formula, R ₁₁ , R ₁₂ , R ₁₃ and R ₁₄ each represent a hydrogen atom or a methyl group, and R ₅ , R ₆ , R ₇ and R ₈ are each a hydrogen atom and a straight chain having 1 to 6 carbon atoms. Or a branched or cyclic alkyl group, an allyl group, a halogen atom, or an aryl group, and R ₉ and R ₁₀ represent a hydrogen atom, a methyl group, or an ethyl group, provided that all of R _{5 to} R ₈ are hydrogen atoms. ( The sum of the carbon number of R _{9 and} the carbon number of R ₁₀ is 0 to 2.)
(Wherein R ₂₁ and R ₂₂ each represent a hydrogen atom or a methyl group, and R ₅ , R ₆ , R ₇ and R ₈ are each a hydrogen atom, a linear, branched or cyclic alkyl having 1 to 6 carbon atoms. A group, an allyl group, a halogen atom, and an aryl group, R ₉ and R ₁₀ represent a hydrogen atom, a methyl group, and an ethyl group, and n represents an integer of 1 to 50, provided that all of R _{5 to} R ₈ are hydrogen. (When it is an atom, the sum of the carbon number of R _{9 and} the carbon number of R ₁₀ is 0 to 2.)
(6) The electrophotographic apparatus according to any one of (1) to (5), wherein the surface layer of the electrophotographic photosensitive member is cured by means using light energy.
(7) The electrophotographic apparatus according to any one of (1) to (6), wherein the conductive fine particles are a metal oxide.

(8) The above-mentioned (1) to (1), wherein the non-radical photosensitive layer of the electrophotographic photoreceptor has a structure in which at least a charge generation layer and a charge transport layer are sequentially laminated on a conductive support. 7) The electrophotographic apparatus according to any one of the above.
(9) A process cartridge for use in the electrophotographic apparatus according to any one of (1) to (8), wherein the electrophotographic photosensitive member, and further a charging unit, an exposure unit, a developing unit, a transfer unit, a cleaning unit, A process cartridge comprising: at least one unit selected from a charge eliminating unit and being detachable from an electrophotographic apparatus.

  An electrophotographic photosensitive member having a photosensitive layer that is not radically cured according to the present invention, and a surface layer that contains a radical curable composition containing the structure of the general formula (A) and conductive fine particles is provided. It has good environmental stability, excellent film strength, small shrinkage, and no cracks. Therefore, by using the electrophotographic photosensitive member in an electrophotographic apparatus of a charging type that directly injects charges, it is possible to perform good injection charging, obtain an excellent image, and the durable life of the photosensitive member. Can provide a sufficiently long electrophotographic apparatus.

Hereinafter, the present invention will be described in detail.
In the present invention, by incorporating the chemical structure of the following general formula (A) into the structure of the radical curable composition that forms the surface layer, it is possible to form a cured surface layer having a small shrinkage rate as well as excellent film strength. It was possible to suppress the occurrence of cracks.
(Expressed in the _{formula, R 5, R 6, R} 7 and R ₈ are each a hydrogen atom, a linear or branched or cyclic alkyl group having 1 to 6 carbon atoms, an allyl group, a halogen atom, an aryl group, R ₉ And R ₁₀ represents a hydrogen atom, a methyl group, or an ethyl group, except that all of R _{5 to} R ₈ are hydrogen atoms, and the sum of the carbon number of R _{9 and} the carbon number of R ₁₀ is 0 to 2. is there.)

<Reason for excellent film strength and crack resistance>
Conventionally, it has been known that a surface layer made of a radically curable composition can form a dense three-dimensional network structure, thereby exhibiting high film strength. As described in JP-A-2004-302451 and JP-A-2006-003863, the factor governing the film strength is important to increase the amount of radical-curable functional groups in the cured composition. In the case of a group, it is disclosed that a denser three-dimensional cross-linked structure is formed and high wear resistance is achieved by using a monomer having a small acrylic equivalent (a value obtained by dividing the monomer molecular weight by the number of functional groups). It is also effective to improve the wear resistance by using a monomer having a large number of functional groups, for example, a monomer having three or more functional groups, and further a hexafunctional monomer. Due to the increase. Therefore, it was expected that the use of a bifunctional or lower monomer as the main component would lower the film strength and reduce the wear resistance of the surface layer.

  On the other hand, the greater the number of functional groups, the higher the hardness of the film and the less the occurrence of surface wear and scratches due to rubbing. However, the more functional groups, the greater the shrinkage rate of the film at the time of curing, and in the electrophotographic photosensitive member, the occurrence of cracks may occur in the surface layer or the lower photosensitive layer.

  On the other hand, in this invention, it became clear that the film intensity | strength more than the case where the said polyfunctional monomer is used by including the structural unit represented by general formula (A) in a radical hardening composition is obtained. This is not seen in the prior art. The reason for this is not clear, but is presumed as follows. In the case where the structural unit of the general formula (A) is contained in the cured composition, the ratio of the functional group is diluted as compared with the polyfunctional aliphatic monomer described in the above publication, and the mechanical strength is considered to decrease. However, although the crosslink density decreases, it is presumed that the effect of entanglement between molecules observed in the linear polymer (in this case, entanglement between structures of the general formula (A)) appears. Moreover, the π-π stacking effect by the π-electron conjugated systems of the general formula (A) appears.

  In addition, intermolecular entanglement and intermolecular interaction due to π-π stacking can significantly suppress film shrinkage during curing, hardly reducing the strength of the cured film, and suppressing cracks in the underlying photosensitive layer. I guess it was possible.

<Excellent environmental stability>
Next, the reason why the crosslinked surface layer of the present invention is resistant to environmental fluctuations and oxidizing gases will be described.
A cross-linked surface layer with high wear resistance originally requires a large amount of reactive substituents to form a dense network structure regardless of the cross-linked structure such as urethane curing, acrylic curing, siloxane curing, and epoxy curing. The crosslinked film also has a large number of polar groups. For this reason, it is vulnerable to environmental fluctuations and oxidizing gases.

  The direction of increasing the functional groups in the radical curing composition described above and the direction of using a large amount of polyfunctional monomers having a large number of functional groups further increase the polar groups (for example, ester groups), resulting in an increase in moisture adsorption. Image flow is likely to occur in a high humidity environment. In addition, when a very dense cross-linked structure is formed, the mobility of the molecule is frozen, and the change of the three-dimensional structure of the charge transport material is suppressed particularly at a low temperature, resulting in a decrease in sensitivity. Further, when the functional group in the cured composition is increased, the unreacted functional group remaining after the curing is increased, and accordingly, the adsorption amount of the highly reactive oxidizing gas generated from the charger is increased, and the crosslinked surface layer is increased. Lowers resistance and lowers resolution.

  On the other hand, by including the structural unit of the general formula (A) in the cured composition of the present invention, the influence of environmental fluctuations and oxidizing gas is alleviated. The reason for this is not clear, but is presumed as follows. When the structural unit of the general formula (A) is contained in the cured composition, it is considered that the environmental stability of the cross-linked surface layer is improved by reducing the functional group concentration as compared with the one using the polyfunctional aliphatic monomer. . In addition, the distance between the actual meshes is widened to keep the molecules easy to move. In addition, the decrease in the polar group does not increase the dielectric constant, so that high charge transportability can be maintained. It is considered possible. Further, it is considered that the bulky structure fills the space of the network structure, so that the gas permeability into the membrane is low and the influence of the oxidizing gas can be reduced. In addition, unlike the bisphenol A structure, the hydrogen of the benzene nucleus is replaced with a bulky linear, branched, or cyclic alkyl group, halogen atom, aryl group, etc. to oxidize to a polar oxygen atom It is thought that the gas resistance was further improved by suppressing the adsorption of the reactive gas.

<About excellent conductive fine particle dispersibility>
Further, the surface layer containing the cured composition having the structural unit of the general formula (A) contains at least conductive fine particles and any radically polymerizable compound of the general formulas (B), (C), and (D). It is preferable to form using a coating liquid. Since the radically polymerizable compounds represented by the general formulas (B), (C), and (D) have an acryl group or a methacryl group, they have a relatively high polarity. For this reason, by dispersing conductive fine particles in a binder resin containing the radical polymerizable compound, there is no formation of secondary particles of dispersed particles, and a coating solution with good dispersibility that is stable over time can be obtained. can get. Furthermore, the surface layer formed from this coating liquid has good transparency, and a film excellent in environmental resistance such as water resistance and chemical resistance can be obtained.

  For the reasons as described above, by containing the structural unit of the general formula (A) in the cured composition of the present invention, it is possible to form a cured surface layer having a small shrinkage rate as well as excellent film strength, and cracks. It is thought that the surface layer which can suppress generation | occurrence | production of was achieved.

<Regarding the radical curable composition>
Next, the components of the radical curable composition that forms the surface layer of the present invention will be described.
In the present invention, the radical curable composition contains the structural unit of the general formula (A), and the radical polymerizable monomer, radical polymerizable oligomer, or polymer having a radical polymerizable functional group having such a structural unit. A radically polymerizable compound such as is cured by radiation energy such as light, heat, or an electron beam to be introduced into the cured product structure in the surface layer. At the time of this curing, the structural unit of the general formula (A) is fixed without being decomposed, and the cured surface layer can be confirmed by MS spectrum measurement by pyrolysis GC analysis, characteristic absorption measurement by infrared spectroscopy, or the like. The structural unit of the general formula (A) is 5 to 80% by weight, preferably 10 to 50% by weight, based on the total amount of the radical curable composition. If it is less than 5% by weight, cracks due to curing shrinkage cannot be suppressed. On the other hand, if it exceeds 80% by weight, there are few curable functional groups, so that the mechanical strength such as abrasion resistance and scratch resistance is lowered, and when the film thickness is increased, the residual potential may be increased.

  The radical polymerizable monomer, oligomer and polymer have a radical polymerizable functional group, and any functional group may be used as long as it has a carbon-carbon double bond and is capable of radical polymerization. Examples of these radical polymerizable functional groups include 1-substituted ethylene functional groups and 1,1-substituted ethylene functional groups shown below.

(1) Examples of the 1-substituted ethylene functional group include a functional group (P) represented by the following formula.
Functional group (P)
CH ₂ = CH-X ₁ -
(In the formula, X ₁ is an arylene group such as a phenylene group or a naphthylene group which may have a substituent, an alkenylene group which may have a substituent, a —CO— group, a —COO— group. , —CON (R ₂₁ ) — group (R ₂₁ represents an alkyl group such as hydrogen, methyl group or ethyl group, an aralkyl group such as benzyl group, naphthylmethyl group or phenethyl group, or an aryl group such as phenyl group or naphthyl group. Or the —S— group.)
Specific examples of these substituents include a vinyl group, a styryl group, a 2-methyl-1,3-butadienyl group, a vinylcarbonyl group, an acryloyloxy group, an acryloylamide group, and a vinyl thioether group.

(2) Examples of the 1,1-substituted ethylene functional group include a functional group (R) represented by the following formula.
Functional group (R)
_{CH 2 = C (Y) -X} 2 -
(In the formula, Y is an aryl group such as an alkyl group which may have a substituent, an aralkyl group which may have a substituent, a phenyl group which may have a substituent, or a naphthyl group. Group, halogen atom, cyano group, nitro group, alkoxy group such as methoxy group or ethoxy group, -COOR ₂₂ group (R ₂₂ is a hydrogen atom, an alkyl such as an optionally substituted methyl group or ethyl group) Group, an aralkyl group such as benzyl and phenethyl group which may have a substituent, an aryl group such as phenyl group and naphthyl group which may have a substituent, or -CONR ₂₃ R ₂₄ (R ₂₃ and R ₂₄ represents a hydrogen atom, an alkyl group such as an optionally substituted methyl group or an ethyl group, an aralkyl group such as an optionally substituted benzyl group, naphthylmethyl group, or phenethyl group; Also Substituent a phenyl group which may have a represents an aryl group such as a naphthyl group, which may be the same or different from each other.) Further, X ₂ is X ₁ same substituent functional group (P) And a single bond or an alkylene group, provided that at least one of Y and X ₂ is an oxycarbonyl group, a cyano group, an alkenylene group, and an aromatic ring.)
Specific examples of these substituents include an α-acryloyloxy chloride group, a methacryloyloxy group, an α-cyanoethylene group, an α-cyanoacryloyloxy group, an α-cyanophenylene group, and a methacryloylamino group.

In addition, examples of the substituent further substituted with the substituent for X ₁ , X ₂ , and Y include alkyl groups such as halogen atom, nitro group, cyano group, methyl group, and ethyl group, methoxy group, and ethoxy group. And an aryloxy group such as a phenoxy group, an aryl group such as a phenyl group and a naphthyl group, and an aralkyl group such as a benzyl group and a phenethyl group.

  Among these radical polymerizable functional groups, acryloyloxy group and methacryloyloxy group are particularly useful. For example, a compound having an acryloyloxy group includes a compound having a hydroxyl group and acrylic acid (salt), acrylic acid halide, acrylic acid. It can be obtained by esterification or transesterification using an ester. A compound having a methacryloyloxy group can be obtained in the same manner. When there are a plurality of radically curable functional groups, they may be the same or different.

<Regarding the radically polymerizable compound of the general formula (B)>
In order to introduce the structural unit of the general formula (A), it is particularly preferable to apply radical curing after coating a coating solution containing a radical polymerizable compound represented by the following general formula (B) on the photosensitive layer. preferable.
(In the formula, R ₁ and R ₂ each represent a linear or branched alkylene group having 1 to 6 carbon atoms, 1-ketohexylene group, R ₃ and R ₄ represent a hydrogen atom or a methyl group, R ₅ , R ₆ , R ₇ and R ₈ each represent a hydrogen atom, a linear, branched or cyclic alkyl group having 1 to 6 carbon atoms, an allyl group, a halogen atom, an aryl group, R ₉ and R ₁₀ are a hydrogen atom, Represents a methyl group and an ethyl group, and n to m each represents an integer of 0 to 4. Except for the case where all of R _{5 to} R ₈ are hydrogen atoms, the number of carbon atoms of R _{9 and} the number of carbon atoms of R ₁₀ The sum is 0-2.)

The radically polymerizable compound represented by the general formula (B) can be easily synthesized, for example, by the following production method.
<When n and m are both 0>
Process B1-1

<When n and m are other than 0>
B2-1 process

B2-2 process

Examples of the radically polymerizable compound represented by the general formula B include the following, but are not limited to these compounds.

<Regarding the radically polymerizable compound of the general formula (C)>
In order to introduce the structural unit of the general formula (A), it is particularly preferable to perform radical curing after coating a coating solution containing a radical polymerizable compound represented by the following general formula (C) on the photosensitive layer. preferable.
(In the formula, R ₁₁ , R ₁₂ , R ₁₃ and R ₁₄ each represent a hydrogen atom or a methyl group, and R ₅ , R ₆ , R ₇ and R ₈ are each a hydrogen atom and a straight chain having 1 to 6 carbon atoms. Or a branched or cyclic alkyl group, an allyl group, a halogen atom, or an aryl group, and R ₉ and R ₁₀ represent a hydrogen atom, a methyl group, or an ethyl group, provided that all of R _{5 to} R ₈ are hydrogen atoms. (The sum of the carbon number of R _{9 and} the carbon number of R ₁₀ is 0 to 2.)

The radically polymerizable compound represented by the general formula (C) can be easily synthesized, for example, by the following production method.
Process C1-1

Process C1-2

Moreover, it can synthesize | combine easily even if it changes a C1-1 process into the following method (C2-1 & C2-2).
Process C2-1

Process C2-2

Further, R ₁₁ to R ₁₄ in the general formula (C) is If all the same group, can be synthesized by the following C3 step.
C3-1 process

C3-2 process

The reaction conditions in each of the above steps can be carried out under the conditions of a conventionally known ring-opening addition reaction of an epoxy ring to a hydroxy group or an esterification reaction with an acid chloride and a hydroxy group.
In addition, conventional synthesis methods other than those described in the steps can be applied. For example, although the (meth) acryloylation step is exemplified in the above step using a reaction between an acid chloride and a hydroxy group, it is also possible to use a dehydration condensation reaction between a suitable acid and a hydroxy group, In acryloylation, the reaction shown in the following (C4) can also be applied.

C4 process

Although the following are illustrated as a radically polymerizable compound represented by general formula (C), it is not limited to these compounds.

<Regarding the radically polymerizable compound of the general formula (D)>
In order to introduce the structural unit represented by the general formula (A), it is particularly preferable to apply a coating solution containing a radical polymerizable compound represented by the following general formula (D) on the photosensitive layer and then to perform radical curing. preferable.
(Wherein R ₂₁ and R ₂₂ each represent a hydrogen atom or a methyl group, and R ₅ , R ₆ , R ₇ and R ₈ are each a hydrogen atom, a linear, branched or cyclic alkyl having 1 to 6 carbon atoms. A group, an allyl group, a halogen atom, and an aryl group, R ₉ and R ₁₀ represent a hydrogen atom, a methyl group, and an ethyl group, and n represents an integer of 1 to 50, provided that all of R _{5 to} R ₈ are hydrogen. (When it is an atom, the sum of the carbon number of R _{9 and} the carbon number of R ₁₀ is 0 to 2.)

The radically polymerizable compound of the general formula (D) is synthesized by the following route.
D1-1 process

D1-2 process

Although the following are illustrated as a radically polymerizable compound represented by general formula (D), It is not limited to these compounds.

  The radically polymerizable compounds of the general formulas (B), (C), and (D) that are preferably used in the present invention are 10 to 100% by weight, preferably 20 to 70% by weight, based on the total amount of the curable constituent material. is there. If these radically polymerizable compounds are less than 10% by weight, the structural unit of the general formula (A) in the cured composition is diluted, and cracks due to curing shrinkage cannot be suppressed. On the other hand, if it exceeds 70% by weight, there are few curable functional groups, so that the mechanical strength such as abrasion resistance and scratch resistance is lowered, and when the film thickness is increased, the residual potential may be increased.

<Regarding monomer having three or more radical polymerizable functional groups>
The surface layer coating solution of the present invention contains a curable composition having the structural unit of the general formula (A), but for the purpose of adjusting wear resistance, hardness, coating solution viscosity, curing rate, etc., radicals are used. A monomer having three or more polymerizable functional groups can be mixed and used. Examples of the radical polymerizable functional group include those described above for the radical polymerizable compound, and acryloyloxy group and methacryloyloxy group are particularly useful.

Examples of the tri- or higher functional radical polymerizable monomer include the following, but are not limited to these compounds.
That is, examples of the trifunctional or higher functional radical polymerizable monomer suitably used in the present invention include trimethylolpropane triacrylate (TMPTA), trimethylolpropane trimethacrylate, trimethylolpropane alkylene-modified triacrylate, trimethylolpropane ethyleneoxy. Modified (hereinafter EO modified) triacrylate, trimethylolpropane propyleneoxy modified (hereinafter PO modified) triacrylate, trimethylolpropane caprolactone modified triacrylate, trimethylolpropane alkylene modified trimethacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate (PETTA) ), Glycerol triacrylate, glycerol epichlorohydrin modified ECH modified) triacrylate, glycerol EO modified triacrylate, glycerol PO modified triacrylate, tris (acryloxyethyl) isocyanurate, dipentaerythritol hexaacrylate (DPHA), dipentaerythritol caprolactone modified hexaacrylate, dipentaerythritol hydroxypentaacrylate , Alkylated dipentaerythritol pentaacrylate, alkylated dipentaerythritol tetraacrylate, alkylated dipentaerythritol triacrylate, dimethylolpropane tetraacrylate (DTMPTA), pentaerythritol ethoxytetraacrylate, EO-modified triacrylate phosphate, 2,2 , 5,5-Tetrahydroxymethylcyclopentanone Such as tigers acrylate and the like, which may be mixed using a single or two or more kinds.

  The amount of the monomer having three or more radically polymerizable functional groups that can be mixed and used in the present invention is 0 to 90% by weight, preferably 0 to 50% by weight, based on the total amount of the curable constituent material. In order to suppress the cracking in curing shrinkage, the amount is preferably equal to or less than the radical polymerizable compound of the general formulas (B), (C), and (D).

<Regarding Additives Having Other Radical Polymerizable Functional Groups>
The surface layer of the present invention contains the structural unit represented by the above general formula (A), but in addition to this, viscosity adjustment at the time of coating, stress relaxation of the surface layer, low surface energy and friction coefficient Monofunctional and bifunctional radically polymerizable monomers, functional monomers, and radically polymerizable oligomers can be used in combination for the purpose of imparting functions such as reduction. Known radical polymerizable monomers and oligomers can be used.

  Examples of the monofunctional radically polymerizable monomer include 2-ethylhexyl acrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, tetrahydrofurfuryl acrylate, 2-ethylhexyl carbitol acrylate, 3-methoxybutyl acrylate, benzyl acrylate, Examples include cyclohexyl acrylate, isoamyl acrylate, isobutyl acrylate, methoxytriethylene glycol acrylate, phenoxytetraethylene glycol acrylate, cetyl acrylate, isostearyl acrylate, stearyl acrylate, and styrene monomer.

  Examples of the bifunctional radical polymerizable monomer include 1,3-butanediol diacrylate, 1,4-butanediol diacrylate, 1,4-butanediol dimethacrylate, 1,6-hexanediol diacrylate, 1, Examples include 6-hexanediol dimethacrylate, diethylene glycol diacrylate, neopentyl glycol diacrylate, bisphenol A-EO modified diacrylate, bisphenol F-EO modified diacrylate, neopentyl glycol diacrylate, and the like.

  Examples of the functional monomer include those substituted with a fluorine atom such as octafluoropentyl acrylate, 2-perfluorooctylethyl acrylate, 2-perfluorooctylethyl methacrylate, 2-perfluoroisononylethyl acrylate, No. 60503, JP-B-6-45770, siloxane repeating units: 20-70 acryloyl polydimethylsiloxane ethyl, methacryloyl polydimethylsiloxane ethyl, acryloyl polydimethylsiloxane propyl, acryloyl polydimethylsiloxane butyl, diacryloyl polydimethylsiloxane Examples include vinyl monomers having a polysiloxane group such as diethyl, acrylates and methacrylates.

Examples of the radical polymerizable oligomer include epoxy acrylate, urethane acrylate, and polyester acrylate oligomers.
However, when a large amount of monofunctional and bifunctional radically polymerizable monomers and radically polymerizable oligomers are contained, the three-dimensional cross-linking density of the surface layer is substantially reduced, resulting in a decrease in wear resistance. For this reason, the content of these monomers and oligomers is limited to 30% by weight or less, preferably 20% by weight or less, based on the total amount of the constituent material having curability of the surface layer.

<Regarding the polymerization initiator>
Further, the surface layer of the present invention contains at least the structural unit represented by the general formula (A) in the radical curable composition, but the surface layer is used to efficiently advance the curing reaction as necessary. A polymerization initiator may be contained in the coating solution.

  Examples of the photopolymerization initiator include diethoxyacetophenone, 2,2-dimethoxy-1,2-diphenylethane-1-one, 1-hydroxy-cyclohexyl-phenyl-ketone, 4- (2-hydroxyethoxy) phenyl- (2 -Hydroxy-2-propyl) ketone, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) butanone-1, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 2- Acetophenone-based or ketal-based photopolymerization initiators such as methyl-2-morpholino (4-methylthiophenyl) propan-1-one, 1-phenyl-1,2-propanedione-2- (o-ethoxycarbonyl) oxime, Benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isobutyl ether Benzoin ether photopolymerization initiators such as benzoin isopropyl ether, benzophenone, 4-hydroxybenzophenone, methyl o-benzoylbenzoate, 2-benzoylnaphthalene, 4-benzoylbiphenyl, 4-benzoylphenyl ether, acrylated benzophenone, Benzophenone photopolymerization initiators such as 1,4-benzoylbenzene, thioxanthones such as 2-isopropylthioxanthone, 2-chlorothioxanthone, 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2,4-dichlorothioxanthone Examples of photopolymerization initiators and other photopolymerization initiators include ethyl anthraquinone, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, 2,4,6-trimethylbenzoic acid. Phenylethoxyphosphine oxide, bis (2,4,6-trimethylbenzoyl) phenylphosphine oxide, bis (2,4-dimethoxybenzoyl) -2,4,4-trimethylpentylphosphine oxide, methylphenylglyoxyester, 9,10 -Phenanthrene, an acridine type compound, a triazine type compound, an imidazole type compound is mentioned. Moreover, what has a photopolymerization acceleration effect can also be used individually or in combination with the said photoinitiator. Examples include triethanolamine, methyldiethanolamine, ethyl 4-dimethylaminobenzoate, isoamyl 4-dimethylaminobenzoate, (2-dimethylamino) ethyl benzoate, 4,4'-dimethylaminobenzophenone, and the like.

Examples of the thermal polymerization initiator include 2,5-dimethylhexane-2,5-dihydroperoxide, dicumyl peroxide, benzoyl peroxide, t-butylcumyl peroxide, 2,5-dimethyl-2,5-di ( Peroxybenzoyl) hexyne-3, di-t-butyl peroxide, t-butyl hydroperoxide, cumene hydroperoxide, lauroyl peroxide, 2,2-bis (4,4-di-t-butylperoxycyclohexyl) B) Peroxide-based initiators such as propane, azo-based compounds such as azobisisobutyronitrile, azobiscyclohexanecarbonitrile, methyl azobisisobutyrate, azobisisobutylamidine hydrochloride, 4,4′-azobis-4-cyanovaleric acid Initiators are mentioned.
These polymerization initiators may be used alone or in combination of two or more. The content of the polymerization initiator is 0.5 to 40 parts by weight, preferably 1 to 20 parts by weight with respect to 100 parts by weight of the total content having radical polymerizability.

<Other additives>
Furthermore, the surface layer coating solution of the present invention may be added with various plasticizers (for the purpose of stress relaxation and adhesion improvement), leveling agents, low molecular charge transport materials having no radical reactivity, binder resins, etc., as necessary. An agent can be contained. As these additives, known additives can be used, and as plasticizers, those used in general resins such as dibutyl phthalate and dioctyl phthalate can be used, and the amount used is the total solid content of the coating liquid. To 20 wt% or less, preferably 10 wt% or less. Moreover, as leveling agents, silicone oils such as dimethyl silicone oil and methylphenyl silicone oil, polymers or oligomers having a perfluoroalkyl group in the side chain can be used, and the amount used is based on the total solid content of the coating liquid. 3% by weight or less is appropriate. Although the low molecular charge transport material is effective for improving the charge transport property of the surface layer and lowering the exposed portion potential, the effect of high wear resistance is reduced because the addition of the curable material decreases. For this reason, the addition amount is adjusted by the process to be used, but it is used at 50% by weight or less, preferably 30% by weight or less, based on the total components of the surface layer. The binder resin has the effect of reducing the internal stress of the surface layer, increasing the uniformity, and suppressing the occurrence of cracks and scratches. However, since the effect of high wear resistance is reduced by addition as in the case of other additives, the addition amount is suppressed to 20% by weight or less, preferably 10% by weight or less.

<Concerning conductive fine particles>
The particle diameter of the conductive fine particles is determined from the transparency of the surface layer. In order to prevent light scattering, 0.3 μm or less is preferable. As the conductive fine particles used in the present invention, metal fine powder and metal oxide particles can be used, but metal oxide is more preferable from the viewpoint of transparency.
As the conductive fine particles used in the present invention, ultrafine particles such as zinc oxide, titanium oxide, tin oxide, antimony oxide, indium oxide, bismuth oxide, tin-doped indium oxide, antimony-doped tin oxide, and zirconium oxide are used. be able to. These metal oxides are used alone or in combination of two or more. When two or more kinds are mixed, they may take the form of a solid solution or fusion.

<Dispersibility of conductive fine particles>
In the surface layer in the present invention, the film strength and the dispersibility uniformity of the conductive fine particles are particularly important. The surface layer of the photoreceptor is exposed to mechanical rubbing such as toner development and cleaning in the electrophotographic process. In particular, the conductive fine particle dispersed film used in the present invention is required to have high strength against abrasion and scratches. In addition, the dispersibility of the conductive fine particles may cause image unevenness due to non-uniform injection charge when they are not uniformly dispersed, and the conductive fine particles are uniformly dispersed in the resin. There is a need.

Conventionally, it is known that the strength of the surface layer and the dispersion uniformity of the conductive fine particles are greatly influenced by the resin of the surface layer, but as the resin for the surface layer used in the present invention, a commercially available polyester, Polycarbonate, polyurethane, acrylic, epoxy, silicone, alkyd, vinyl chloride-vinyl acetate copolymer and the like can also be used in combination. Further, as a result of studies for suppressing cracks and improving film strength and dispersibility, in the radical polymerizable compound represented by at least the general formulas (B), (C) and (D) constituting the general formula (A) By using a surface layer formed by dispersing conductive particles on the surface and applying and curing the conductive particles on the photosensitive layer of the photoreceptor, it is possible to suppress cracks and dramatically improve film strength and dispersibility of conductive particles. Improved.
Even if mixed with the above-mentioned polyester, polycarbonate, polyurethane, acrylic, epoxy, silicone, alkyd, vinyl chloride-vinyl acetate copolymer, etc., the cracks can be sufficiently suppressed, the film strength, and the conductive particles can be dispersed. The effect on sex is achieved.
Various additives can be added for the purpose of improving the dispersibility of the conductive particles and improving the adhesion or smoothness. In particular, it is very effective to disperse a lubricant such as fluorine-containing resin fine particles such as polytetrafluoroethylene and fluorocarbon particles and silicone fine particles for the purpose of improving characteristics such as cleaning properties.

<About the ratio of the electroconductive particle of a surface layer>
The ratio between the resin and the conductive fine particles in the surface layer is a value that directly determines the resistance of the charge injection layer, and is 10 ¹⁰ to 10 ¹⁵ (Ω · cm), and preferably 10 ¹⁰ to 10 ¹⁴ (Ω · cm). More preferably, it is 10 ¹¹ to 10 ¹³ (Ω · cm).

<Regarding coating solvent>
The surface layer of the present invention is formed by applying and curing a coating solution containing at least conductive fine particles and a radical polymerizable compound containing the structural unit of the general formula (A) on the photosensitive layer described later. . When the radically polymerizable compound is a liquid, such a coating liquid can be applied by dissolving other components in the liquid, but if necessary, it is diluted with a solvent and applied. Solvents used at this time include alcohols such as methanol, ethanol, propanol and butanol, ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone, esters such as ethyl acetate and butyl acetate, tetrahydrofuran, dioxane and propyl ether. And ethers such as dichloromethane, dichloroethane, trichloroethane, and chlorobenzene, aromatics such as benzene, toluene, and xylene, and cellosolves such as methyl cellosolve, ethyl cellosolve, and cellosolve acetate. These solvents may be used alone or in combination of two or more. The dilution ratio with the solvent varies depending on the solubility of the composition, the coating method, and the target film thickness, and is arbitrary. The coating can be performed using a dip coating method, spray coating, bead coating, ring coating method or the like.

In this invention, after apply | coating this surface layer coating liquid, energy is given from the outside and it hardens | cures and forms a surface layer, As an external energy used at this time, there exists light, a heat | fever, or a radiation. As the energy of light, UV irradiation light sources such as high-pressure mercury lamps and metal halide lamps, which mainly have an emission wavelength in ultraviolet light, can be used, but a visible light source can also be selected according to the absorption wavelength of radically polymerizable substances and photopolymerization initiators. Is possible. Irradiation light amount is 50 mW / cm ² or more, preferably 1000 mW / cm ² or less, it takes time for the curing reaction is less than 50 mW / cm ^2. If it is higher than 1000 mW / cm ^2, the progress of the reaction becomes non-uniform, and local flaws are generated on the surface of the surface layer, and a large number of unreacted residues and reaction termination ends are generated. In addition, internal stress increases due to rapid crosslinking, which causes cracks and film peeling. The irradiation time depends on the UV light penetrability depending on the constituent material and the film thickness, but is preferably 5 seconds to 5 minutes. If it is too short, curing will be insufficient, and if it is too long, the constituent material will be decomposed and the electrical properties will deteriorate. In addition, it is desirable to control the temperature rise during curing to 50 ° C. or less to suppress decomposition of the constituent materials and uneven curing reaction.

When curing using thermal energy, 10 minutes to 3 hours are preferable at 100 to 170 ° C., and curing is insufficient at a temperature lower than 100 ° C. or a time shorter than 10 minutes. On the other hand, at a temperature higher than 170 ° C. or longer than 3 hours, decomposition of the constituent materials and non-uniform curing reaction proceed, and a good surface layer cannot be obtained.
An electron beam is preferably used as the energy of radiation. The acceleration voltage of the electron beam is 300 KV or less, preferably 150 KV or less, and the dose is cured under the conditions of 1 to 100 Mrad. When the acceleration voltage exceeds 300 KV or the dose exceeds 100 Mrad, the decomposition of the constituent materials proceeds, and the effect of the present invention is not exhibited.
Among these energies, those using light energy are useful because of the ease of reaction rate control and the simplicity of the apparatus.

<About the film thickness of the surface layer>
The film thickness of the surface layer of the present invention is preferably 0.1 to 10 μm and more preferably 0.5 to 7 μm from the viewpoint of film strength and charge injection property.

Hereinafter, the present invention will be described according to the layer structure.
<About the layer structure of the electrophotographic photoreceptor>
The electrophotographic photosensitive member used in the present invention will be described with reference to the drawings.
1 and 2 are sectional views showing the electrophotographic photosensitive member of the present invention.
FIG. 1 shows a case where a photosensitive layer having a charge generation function and a charge transport function at the same time is provided on a conductive support, and the surface layer is the surface portion of the photosensitive layer. That is, the photosensitive layer which is not radically cured represents a photosensitive layer having the charge generating function and the charge transporting function shown in the figure at the same time, and the surface layer containing the radical curable composition represents the surface layer shown in the figure.

  FIG. 2 shows a photoreceptor having a laminated structure in which a charge generation layer having a charge generation function and a charge transport layer having a charge transport material function are laminated as a photosensitive layer on a conductive support. The case where the surface layer is the surface portion of the charge transport layer is shown. That is, the photosensitive layer that is not radically cured represents the charge generation layer and the charge transport layer in the figure, and the surface layer containing the radical curable composition represents the surface layer in the figure.

<About conductive support>
Examples of the conductive support include those having a volume resistance of 10 ¹⁰ Ω · cm or less, such as metals such as aluminum, nickel, chromium, nichrome, copper, gold, silver, and platinum, tin oxide, and indium oxide. After metal oxide is deposited or sputtered, film or cylindrical plastic, paper coated, or aluminum, aluminum alloy, nickel, stainless steel, etc. Pipes that have been subjected to surface treatment such as cutting, super-finishing, and polishing can be used. Further, endless nickel belts and endless stainless steel belts disclosed in JP-A-52-36016 can also be used as the conductive support.
In addition, those obtained by dispersing and coating conductive powder in an appropriate binder resin on the support can also be used as the conductive support of the present invention.

Examples of the conductive powder include carbon black, acetylene black, metal powder such as aluminum, nickel, iron, nichrome, copper, zinc and silver, or metal oxide powder such as conductive tin oxide and ITO. Can be mentioned. The binder resin used at the same time is polystyrene, styrene-acrylonitrile copolymer, styrene-butadiene copolymer, styrene-maleic anhydride copolymer, polyester, polyvinyl chloride, vinyl chloride-vinyl acetate copolymer. , Polyvinyl acetate, polyvinylidene chloride, polyarylate resin, phenoxy resin, polycarbonate, cellulose acetate resin, ethyl cellulose resin, polyvinyl butyral, polyvinyl formal, polyvinyl toluene, poly-N-vinylcarbazole, acrylic resin, silicone resin, epoxy resin, Examples thereof include thermoplastic, thermosetting resins, and photocurable resins such as melamine resin, urethane resin, phenol resin, and alkyd resin. Such a conductive layer can be provided by dispersing and coating these conductive powder and binder resin in a suitable solvent such as tetrahydrofuran, dichloromethane, methyl ethyl ketone, and toluene.
Furthermore, it is electrically conductive by a heat shrinkable tube in which the conductive powder is contained in a material such as polyvinyl chloride, polypropylene, polyester, polystyrene, polyvinylidene chloride, polyethylene, chlorinated rubber, and Teflon (registered trademark) on a suitable cylindrical substrate. Those provided with a conductive layer can also be used favorably as the conductive support of the present invention.

<About photosensitive layer>
Next, the photosensitive layer will be described. The photosensitive layer may have a laminated structure or a single layer structure.
In the case of a laminated structure, the photosensitive layer is composed of a charge generation layer having a charge generation function and a charge transport layer having a charge transport function. In the case of a single layer structure, the photosensitive layer is composed of a layer having a charge generation function and a charge transport function at the same time.
Hereinafter, each of the photosensitive layer having a laminated structure and the photosensitive layer having a single layer structure will be described.

<Photosensitive layer with a laminated structure>
(1) Charge generation layer The charge generation layer is a layer mainly composed of a charge generation material having a charge generation function, and a binder resin can be used in combination as necessary. As the charge generation material, inorganic materials and organic materials can be used.
Inorganic materials include crystalline selenium, amorphous selenium, selenium-tellurium, selenium-tellurium-halogen, selenium-arsenic compounds, and amorphous silicon. In amorphous silicon, dangling bonds that are terminated with hydrogen atoms or halogen atoms, or those that are doped with boron atoms, phosphorus atoms, or the like are preferably used.
On the other hand, a known material can be used as the organic material. For example, phthalocyanine pigments such as metal phthalocyanine and metal-free phthalocyanine, azulenium salt pigments, squaric acid methine pigments, azo pigments having carbazole skeleton, azo pigments having triphenylamine skeleton, azo pigments having diphenylamine skeleton, dibenzothiophene skeleton Azo pigments having a fluorenone skeleton, azo pigments having an oxadiazole skeleton, azo pigments having a bis-stilbene skeleton, azo pigments having a distyryl oxadiazole skeleton, azo pigments having a distyrylcarbazole skeleton, perylene Pigments, anthraquinone or polycyclic quinone pigments, quinoneimine pigments, diphenylmethane and triphenylmethane pigments, benzoquinone and naphthoquinone pigments, cyanine and azomethine pigments, Goido based pigments, and bisbenzimidazole pigments. These charge generation materials can be used alone or as a mixture of two or more.

  As a binder resin used as necessary for the charge generation layer, polyamide, polyurethane, epoxy resin, polyketone, polycarbonate, silicone resin, acrylic resin, polyvinyl butyral, polyvinyl formal, polyvinyl ketone, polystyrene, poly-N-vinylcarbazole, Examples include polyacrylamide. These binder resins can be used alone or as a mixture of two or more. In addition to the binder resin described above as a binder resin for the charge generation layer, a polymer charge transport material having a charge transport function, such as an arylamine skeleton, benzidine skeleton, hydrazone skeleton, carbazole skeleton, stilbene skeleton, pyrazoline skeleton, etc. Polymer materials such as polycarbonate, polyester, polyurethane, polyether, polysiloxane, and acrylic resin, polymer materials having a polysilane skeleton, and the like can be used.

  Specific examples of the former include JP-A-01-001728, JP-A-01-009964, JP-A-01-013061, JP-A-01-019049, JP-A-01-241559, Japanese Unexamined Patent Publication Nos. 04-011627, 04-175337, 04-183719, 04-2225014, 04-230767, 04-320420, 05 -232727, JP-A 05-310904, JP-A 06-234836, JP-A 06-234837, JP-A 06-234838, JP-A 06-234839, JP-A 06-234840. No. 1, JP-A 06-234841, JP-A 06-239049, Japanese Unexamined Patent Publication Nos. 06-236050, 06-236051, 06-295077, 07-0756374, 08-176293, 08-208820, 08 No. -21640, JP 08-253568, JP 08-269183, JP 09-062019, JP 09-043883, JP 09-71642, JP 09-87376. No. 1, JP-A 09-104746, JP 09-110974, JP 09-110976, JP 09-157378, JP 09-221544, JP 09-227669. JP 09-235367 A, JP 09-241369 A Charge transporting polymer materials described in JP 09-268226 A, JP 09-272735 A, JP 09-302084 A, JP 09-302085 A, JP 09-328539 A, etc. Can be mentioned.

  Specific examples of the latter include polysilylene polymers described in, for example, JP-A No. 63-285552, JP-A No. 05-19497, JP-A No. 05-70595, JP-A No. 10-73944, and the like. Illustrated.

The charge generation layer may contain a low molecular charge transport material.
Low molecular charge transport materials that can be used in the charge generation layer include hole transport materials and electron transport materials.
Examples of the electron transporting material include chloroanil, bromanyl, tetracyanoethylene, tetracyanoquinodimethane, 2,4,7-trinitro-9-fluorenone, 2,4,5,7-tetranitro-9-fluorenone, 2,4 , 5,7-tetranitroxanthone, 2,4,8-trinitrothioxanthone, 2,6,8-trinitro-4H-indeno [1,2-b] thiophen-4-one, 1,3,7-tri Examples thereof include electron-accepting substances such as nitrodibenzothiophene-5,5-dioxide and diphenoquinone derivatives. These electron transport materials can be used alone or as a mixture of two or more.

  Examples of the hole transporting material include the electron donating materials shown below and are used favorably. As hole transport materials, oxazole derivatives, oxadiazole derivatives, imidazole derivatives, monoarylamine derivatives, diarylamine derivatives, triarylamine derivatives, stilbene derivatives, α-phenylstilbene derivatives, benzidine derivatives, diarylmethane derivatives, triaryls Other known materials such as methane derivatives, 9-styrylanthracene derivatives, pyrazoline derivatives, divinylbenzene derivatives, hydrazone derivatives, indene derivatives, butadiene derivatives, pyrene derivatives, bisstilbene derivatives, enamine derivatives, and the like can be given. These hole transport materials can be used alone or as a mixture of two or more.

Methods for forming the charge generation layer include a vacuum thin film preparation method and a casting method from a solution dispersion system.
As the former method, a vacuum deposition method, a glow discharge decomposition method, an ion plating method, a sputtering method, a reactive sputtering method, a CVD method, or the like is used, and the above-described inorganic materials and organic materials can be satisfactorily formed.
In addition, in order to provide a charge generation layer by the casting method described later, if necessary, the inorganic or organic charge generation material together with a binder resin, tetrahydrofuran, dioxane, dioxolane, toluene, dichloromethane, monochlorobenzene, dichloroethane, cyclohexanone, cyclohexane. Can be formed by dispersing with a ball mill, attritor, sand mill, bead mill, etc. using a solvent such as pentanone, anisole, xylene, methyl ethyl ketone, acetone, ethyl acetate, butyl acetate, etc. . Moreover, leveling agents, such as a dimethyl silicone oil and a methylphenyl silicone oil, can be added as needed. The coating can be performed using a dip coating method, spray coating, bead coating, ring coating method or the like.
The thickness of the charge generation layer provided as described above is suitably about 0.01 to 5 μm, preferably 0.05 to 2 μm.

(2) Charge Transport Layer The charge transport layer is formed by dissolving or dispersing a charge transport material having a charge transport function and a binder resin in a suitable solvent, and applying and drying the solution on the charge generation layer.
As the charge transport material, the electron transport material, hole transport material and polymer charge transport material described in the charge generation layer can be used. In particular, the use of a polymer charge transport material is particularly useful because it has an effect of reducing the solubility of the lower layer during coating of the surface layer.
As the binder resin, polystyrene, styrene-acrylonitrile copolymer, styrene-butadiene copolymer, styrene-maleic anhydride copolymer, polyester, polyvinyl chloride, vinyl chloride-vinyl acetate copolymer, polyvinyl acetate, Polyvinylidene chloride, polyarylate resin, phenoxy resin, polycarbonate, cellulose acetate resin, ethyl cellulose resin, polyvinyl butyral, polyvinyl formal, polyvinyl toluene, poly-N-vinyl carbazole, acrylic resin, silicone resin, epoxy resin, melamine resin, urethane resin And thermoplastic or thermosetting resins such as phenol resins and alkyd resins.
The amount of the charge transport material is appropriately 20 to 300 parts by weight, preferably 40 to 150 parts by weight, based on 100 parts by weight of the binder resin. However, when a polymer charge transport material is used, it can be used alone or in combination with a binder resin.

  As the solvent used for coating the charge transport layer, the same solvent as that used for the charge generation layer can be used, but a solvent that dissolves the charge transport material and the binder resin is suitable. These solvents may be used alone or in combination of two or more. The charge transport layer can be formed by the same coating method as that for the charge generation layer.

If necessary, a plasticizer and a leveling agent can be added.
As the plasticizer that can be used in combination with the charge transport layer, those generally used as resin plasticizers such as dibutyl phthalate and dioctyl phthalate can be used as they are, and the amount used is based on 100 parts by weight of the binder resin. About 0 to 30 parts by weight is appropriate.
Leveling agents that can be used in combination with the charge transport layer include silicone oils such as dimethyl silicone oil and methylphenyl silicone oil, and polymers or oligomers having a perfluoroalkyl group in the side chain. The amount used is a binder resin. About 0 to 1 part by weight is appropriate for 100 parts by weight.
The thickness of the charge transport layer is suitably about 5 to 40 μm, preferably about 10 to 30 μm.

<Single photosensitive layer>
The photosensitive layer having a single layer structure is a layer having a charge generation function and a charge transport function at the same time.
When the photosensitive layer is a layer having both a charge generation function and a charge transport function, the photosensitive layer dissolves or disperses a charge generation material having a charge generation function, a charge transport material having a charge transport function, and a binder resin in an appropriate solvent. It can be formed by coating and drying. Moreover, a plasticizer, a leveling agent, etc. can also be added as needed. As the charge generation material dispersion method, the charge generation material, the charge transport material, the plasticizer, and the leveling agent may be the same as those already described in the charge generation layer and the charge transport layer. As the binder resin, in addition to the binder resin previously mentioned in the section of the charge transport layer, the binder resin mentioned in the charge generation layer may be mixed and used. In addition, the above-described polymer charge transport materials can be used, which is useful in that contamination of the photosensitive layer composition into the surface layer can be reduced. The charge generation material contained in the photosensitive layer is preferably 1 to 30% by weight based on the total amount of the photosensitive layer, the binder resin contained in the photosensitive layer is 20 to 80% by weight, and the charge transport material is 10 to 70% by weight. % Is used well.
The film thickness of the photosensitive layer is 5 to 30 μm, preferably 10 to 25 μm.

<About the intermediate layer>
In the photoreceptor of the present invention, when the surface layer is the surface portion of the photosensitive layer, an intermediate layer can be provided between the surface layer and the photosensitive layer. This intermediate layer prevents inhibition of the curing reaction and unevenness of the surface layer caused by mixing of the photosensitive layer composition that is not radically cured into the surface layer containing the radical curable composition. It is also possible to improve the adhesion between the photosensitive layer and the surface layer.
In the intermediate layer, a binder resin is generally used as a main component. Examples of these resins include polyamide, alcohol-soluble nylon, water-soluble polyvinyl butyral, polyvinyl butyral, and polyvinyl alcohol. As a method for forming the intermediate layer, a generally used coating method is employed as described above. In addition, about 0.05-2 micrometers is suitable for the thickness of an intermediate | middle layer.

<About the undercoat layer>
In the photoreceptor of the present invention, an undercoat layer can be provided between the conductive support and the photosensitive layer. In general, the undercoat layer is mainly composed of a resin. However, considering that the photosensitive layer is coated with a solvent on these resins, the resin may be a resin having high solvent resistance with respect to a general organic solvent. desirable. Examples of such resins include water-soluble resins such as polyvinyl alcohol, casein, and sodium polyacrylate, alcohol-soluble resins such as copolymer nylon and methoxymethylated nylon, polyurethane, melamine resin, phenol resin, alkyd-melamine resin, and epoxy. Examples thereof include a curable resin that forms a three-dimensional network structure such as a resin. Further, a metal oxide fine powder pigment exemplified by titanium oxide, silica, alumina, zirconium oxide, tin oxide, indium oxide and the like may be added to the undercoat layer in order to prevent moire and reduce residual potential.

These undercoat layers can be formed using an appropriate solvent and a coating method like the above-mentioned photosensitive layer. Furthermore, a silane coupling agent, a titanium coupling agent, a chromium coupling agent, or the like can be used as the undercoat layer of the present invention. In addition, in the undercoat layer of the present invention, Al ₂ O ₃ is provided by anodic oxidation, organic substances such as polyparaxylylene (parylene), SiO ₂ , SnO ₂ , TiO ₂ , ITO, CeO ₂ A material provided with an inorganic material such as a vacuum thin film can also be used favorably. In addition, known ones can be used. The thickness of the undercoat layer is 0.5 to 20 μm, preferably 3 to 6 μm.

<Addition of antioxidant to each layer>
Further, in the present invention, in order to improve environmental resistance, each layer such as a surface layer, a charge generation layer, a charge transport layer, an undercoat layer, an intermediate layer, etc., in particular for the purpose of preventing a decrease in sensitivity and an increase in residual potential An antioxidant can be added to the.
The following are mentioned as antioxidant which can be used for this invention.
(Phenolic compounds)
2,6-di-t-butyl-p-cresol, butylated hydroxyanisole, 2,6-di-t-butyl-4-ethylphenol, stearyl-β- (3,5-di-t-butyl-4 -Hydroxyphenyl) propionate, 2,2'-methylene-bis- (4-methyl-6-tert-butylphenol), 2,2'-methylene-bis- (4-ethyl-6-tert-butylphenol), 4, 4'-thiobis- (3-methyl-6-tert-butylphenol), 4,4'-butylidenebis- (3-methyl-6-tert-butylphenol), 1,1,3-tris- (2-methyl-4 -Hydroxy-5-t-butylphenyl) butane, 1,3,5-trimethyl-2,4,6-tris (3,5-di-t-butyl-4-hydroxybenzyl) benzene, tetrakis- [methylene- -(3 ', 5'-di-t-butyl-4'-hydroxyphenyl) propionate] methane, bis [3,3'-bis (4'-hydroxy-3'-t-butylphenyl) butyric acid] Glycol esters, tocopherols and the like.

(Paraphenylenediamines)
N-phenyl-N'-isopropyl-p-phenylenediamine, N, N'-di-sec-butyl-p-phenylenediamine, N-phenyl-N-sec-butyl-p-phenylenediamine, N, N'- Di-isopropyl-p-phenylenediamine, N, N′-dimethyl-N, N′-di-t-butyl-p-phenylenediamine and the like.
(Hydroquinones)
2,5-di-t-octylhydroquinone, 2,6-didodecylhydroquinone, 2-dodecylhydroquinone, 2-dodecyl-5-chlorohydroquinone, 2-t-octyl-5-methylhydroquinone, 2- (2-octadecenyl) ) -5-methylhydroquinone and the like.

(Organic sulfur compounds)
Dilauryl-3,3′-thiodipropionate, distearyl-3,3′-thiodipropionate, dimyristyl-3,3′-thiodipropionate, ditetradecyl-3,3′-thiodipropionate, penta Erythritol tetrakis (3-laurylthio-propionate) and the like.
(Organic phosphorus compounds)
Triphenyl phosphite, tris (nonylphenyl) phosphite, tri (dinonylphenyl) phosphite, tris (2-ethylhexyl) phosphite, tridecyl phosphite, tris (tridecyl) phosphite, diphenyl mono (2-ethylhexyl) Phosphite, diphenyl monodecyl phosphite, tris (2,4, di-t-butylphenyl) phosphite, distearyl pentaerythritol diphosphite, bis (2,4, di-t-butylphenyl) pentaerythritol phosphite 2,2-methylenebis (4,6-di-t-butylphenyl) octyl phosphite, tetrakis (2,4-di-t-butylphenyl) 4,4′-biphenylene-di-phosphonite, dilauryl hydrogenphos Fight, diphenyl Hydrogen phosphite, tetraphenyldipropylene glycol diphosphite, tetraphenyltetra (tridecyl) pentaerythritol tetraphosphite, tetra (tridecyl) -4,4′isopropylidene diphenyldiphosphite, bis (nonylphenyl) pentaerythritol diphos Phyto, hydrogenated bisphenol A, pentaerythritol phosphite polymer, etc.
These compounds are known as antioxidants such as rubbers, plastics and fats and oils, and commercially available products can be easily obtained.
The addition amount of the antioxidant in the present invention is 0.01 to 10% by weight based on the total weight of the layer to be added.

Next, the charging method in the present invention will be described. The charging method of the present invention is a contact charging method that does not involve a discharge phenomenon. In other words, this is a charge injection charging method capable of charging the photoconductor with a potential corresponding to the voltage applied to the contact charging device. Since this method does not involve discharge, less ozone and nitrogen oxide are generated, and the applied voltage for charging the photosensitive member is lower than that of the process using the conventional contact charging method, so that energy is saved. .
The photoreceptor to be used is provided with a surface layer having the function of a charge injection layer as the outermost layer described above. The charge injection layer serves as a so-called capacitor electrode. When a conductive contact charging member is brought into contact with this electrode and a voltage is applied, charge can be injected. In the absence of such a charge injection layer, there is nothing that can serve as an electrode on the surface of the photoreceptor, and sufficient charge injection cannot be performed.

By providing the charge injection layer on the surface of the photosensitive layer, a uniform charge sheet can be formed on the surface of the photosensitive layer below the charge injection layer. The charge injection layer is required to have a characteristic that a charge applied by a contact charging device is quickly transferred to the surface layer of the photosensitive layer to form a uniform charge sheet.
In order to form a uniform charge sheet, both the charge injection layer and the contact charging device must have characteristics such as uniform contact property, nip, contact resistance, and volume resistivity of the member. Must be set.

As the contact charging method, there is an example as shown in FIG.
3 (I) is a magnetic brush charging method, FIG. 3 (II) is a (conductive) brush charging method, FIG. 3 (III) is a roller charging method using a conductive soft roller, and FIG. 3 (IV) is fixed. FIG. 3 (V) shows a belt-type charging method using two rollers and a conductive belt.
In order to charge the photoconductor uniformly without discharge, ensure the necessary nip with the photoconductor with the appropriate applied voltage, reduce the gap between the photoconductor and the charger as much as possible, and make the contact as dense as possible. There is a need to.

In the magnetic brush charging method of FIG. 3 (I), a spherical roller of about 20 to 150 μm is formed on a magnetic roller formed by covering a magnet roller with alternately arranged S and N pole magnets with a sleeve of a nonmagnetic material such as aluminum or bakelite. Alternatively, magnetic particles such as substantially spherical ferrite, manganese oxide, and gamma ferric oxide, or fine particles coated on them for the purpose of improving fluidity, such as polyester resin or fluororesin, protective layer, etc., have a thickness of about 1 to 5 mm. Then, a layer formed by suction is used.
The resistance value of the fine particles is usually in the range of 10 ⁵ Ω · cm to ^{10 10} Ω · cm, and the lower the resistance, the better the charge injection property. It is also possible to form a cleaningless process by using a magnetic brush.

The conductive brush charging method shown in FIG. 3 (II) is a conductive treatment of fibers such as rayon, acrylic, polypropylene, polyester, and polyacrylonitrile with carbon or copper sulfide, or conductive properties such as zinc oxide, tin oxide, and titanium oxide. It is made into a brush using a member that is spun with a fiber kneaded with a filler or knitted with a metal yarn.
In addition, carbon fibers or activated carbon fibers obtained by firing the fibers in an inert gas atmosphere can be used.
The resistance of the member of the contact charging device is preferably in the range of 10 ² Ω · cm to ^{10 10} Ω · cm.
Carbon fiber and activated carbon fiber can freely change the deposition resistivity at the firing temperature. When the carbon component is 90% or more, the resistance is as extremely low as about 10 ² Ω · cm. Accordingly, there is a risk of electric discharge destruction when the photoconductor has a pinhole, but there is no problem when it is used at a low voltage. Usually, a protective resistance of about 100 KΩ to 5 MΩ is inserted in series between the voltage supply source and used.

The (soft) roller charging method of FIG. 3 (III) is suitable for increasing the nip with the photoconductor and improving the adhesion with the photoconductor. The soft roller is made of soft rubber, soft foam (urethane sponge, foam, etc.), and the surface layer or the entire layer is subjected to a conductive treatment. Examples of the conductive treatment material include conductive fillers such as SnO ₂ , TiO ₂ , ZnO ₂ , and carbon black, and conductive fibers such as carbon fibers and activated carbon fibers.
The fixed (blade) charging method of FIG. 3 (IV) is a method of charging in such a manner that the photosensitive member is rubbed, and the above-mentioned members can be used almost.
Constitution includes, for example, finely woven carbon fiber or activated carbon fiber as a charging member on an elastic member such as sponge or foam (produced by Unitika, Toho Rayon, Veslon, etc., FW210, 310, etc. in the example of Toho Rayon) In such a shape as to cover the surface, charging is performed by contacting the photosensitive member.

The belt-type charging device in FIG. 3 (V) is a good means for earning a nip with the photoreceptor. As materials that can be used, members described in the conductive brush charging method and the roller charging method can be used.
The wider the nip necessary for contact with the photoreceptor, the better. However, it is usually sufficient that the nip is about 3 mm to 10 mm or more, and it is desirable that the contact with the photoreceptor is evenly and uniformly.
When the various members described above are used as a charging member, the volume resistivity is desirably 10 ² Ω · cm to 10 ¹⁰ Ω · cm, and preferably 10 ⁸ Ω · cm or less. The higher the resistance, the lower the charge injection property. If it is too low, there is no problem with the charge injection property, but if there is a pinhole in the photoconductor, there is a risk of causing a power supply break or horizontal black streaks on the image. Usually, since the charging level of the photoreceptor is about −500 to −800 V, the risk of discharge breakdown is small, and even if ozone is generated, the practical effect is small.
The photoreceptor of the present invention can be used in a general electrophotographic process including a charge injection charging method.

Next, an electrophotographic process cartridge which is an example of the electrophotographic process of the present invention will be described. In the process cartridge, units such as a charging unit, a developing unit, and a cleaning unit are integrated, and attachment and removal are simple. FIG. 4 shows an example of the electrophotographic process cartridge. The electrophotographic process of the present invention will be described along the description of this schematic cross-sectional view.
In the figure, reference numeral 11 denotes an electrophotographic photoreceptor of the present invention. First, the photosensitive member is charged by injection with a charging device 12 (the charger in FIG. 3 (III) in the figure). After the photosensitive member is charged, the image exposure 13 is received, and an electric charge is generated in the exposed portion, and an electrostatic latent image is formed on the surface of the photosensitive member. After the electrostatic latent image is formed on the surface of the photoreceptor, the toner image is formed by contacting with the developer via the developing roller 14. The toner image formed on the surface of the photoreceptor is transferred to the transfer member 15 such as paper by the transfer roller 16 and passes through the fixing unit 19 to become a hard copy. Residual toner on the electrophotographic photoreceptor 11 is removed by the cleaning unit 17, and the residual charge is removed by the charge eliminating lamp 18, and the process proceeds to the next electrophotographic cycle.

  The electrophotographic process using the present image forming method and the photoreceptor is not limited to the above example, and is any process that forms an electrostatic latent image by at least charging and exposure. It doesn't matter. In particular, in this image forming method, the toner transfer efficiency is improved and the toner remaining after the transfer is cleanerless without using a cleaning unit and collected by a charging device or a developing device. Desirable because of low load.

<Synthesis example 1 of exemplary compound B-1-1 used in the present invention>
(1) Synthesis of B-1-1
30 g of 2,2-bis (3-methyl-4-hydroxyphenyl) propane was dissolved in 200 ml of tetrahydrofuran, and sodium hydroxide (NaOH: 118.7 g, water: 75 ml) was added dropwise in a nitrogen stream. This solution was cooled to 6 ° C., and 42.4 g of acrylic acid chloride was added dropwise over 1 hour. Thereafter, the reaction was terminated by stirring for 2.5 hours. The reaction solution was poured into water and extracted with toluene. This extract was repeatedly washed with water. The reaction solution was poured into water and extracted with toluene. Thereafter, the solvent was removed from the toluene solution, and purification was performed by column chromatography (adsorption medium: silica gel, developing solvent: toluene / ethyl acetate (1/1)). Methanol was added to the obtained colorless oil to precipitate crystals. Thus, Exemplified Compound NO. 21.43 g (yield = 50.2%) of white crystals of B-1-1 were obtained. The melting point and elemental analysis value of the obtained compound are shown below. An infrared absorption spectrum is shown in FIG.
Melting point: 50.5-51.5 ° C

<Synthesis example 1 of exemplary compound C-1-1 used in the present invention>
(1) Synthesis of 2,2-bis {3-methyl-4- (2,3-dihydroxypropyloxy) phenyl} propane
8.57 g of 2,2-bis (3-methyl-4-hydroxyphenyl) propane and 11.01 g of glycidyl methacrylate were dissolved in 50 ml of toluene, 0.3 ml of triethylamine was added, and the mixture was stirred at 95 ° C. for 9 hours in an argon stream. . Thereafter, 33 ml of a 10 wt% sodium hydroxide solution and 30 ml of toluene were added at room temperature, and the mixture was stirred at 92 ° C. for 6 hours to complete the reaction. The reaction solution was neutralized with hydrochloric acid, extracted with ethyl acetate, and washed repeatedly with water. Thereafter, the solvent was removed from the ethyl acetate solution, and purification was performed by column chromatography (adsorption medium: silica gel, developing solvent: ethyl acetate / THF (1/1)). In this way, 8.64 g (yield = 87%) of the following structural formula A in the form of a colorless powder was obtained. The infrared absorption spectrum of the obtained compound is shown in FIG.

(2) Synthesis of C-1-1
8.64 g of 2,2-bis {3-methyl-4- (2,3-dihydroxypropyloxy) phenyl} propane was dissolved in 87 ml of dimethylacetamide. 16.75 g of 3-chloropropionic acid chloride was added at 3 ° C. in an argon stream and stirred at room temperature for 7 hours. Thereafter, 29 ml of triethylamine was added at 3 ° C., and the mixture was stirred at 60 for 5 hours to complete the reaction. The reaction solution was poured into water and extracted with dichloromethane. This extract was repeatedly washed with water. Thereafter, the solvent was removed from the dichloromethane solution, and purification was performed by column chromatography (adsorption medium: silica gel, developing solvent: n-hexane / ethyl acetate (2/1)). In this way, 10.19 g (yield = 77%) of oily exemplary compound C-1-1 was obtained. Elemental analysis values of the obtained compound are shown below. An infrared absorption spectrum is shown in FIG.

<The synthesis example of exemplary compound D-1-1 used by this invention>
In a reaction vessel equipped with a stirrer, thermometer and dropping funnel, 5.1 g (0.020 mol) of 2,2-bis (3-methyl-4-hydroxyphenyl) propane, 18.51 g (200 mmol) of epichlorohydrin, 20 ml of toluene. And heated and stirred at 110 ° C. under a nitrogen stream. To this, 9.60 g (48 mmol) of a 20 wt% aqueous sodium hydroxide solution was added dropwise over 30 minutes so that the temperature in the reaction system was maintained at 100 ° C. to 120 ° C., and reacted at 110 ° C. for 4 hours. This was allowed to cool to room temperature, and excess epichlorohydrin was recovered under reduced pressure, and then toluene was added to wash the organic layer with water. The toluene solution was dried over anhydrous magnesium sulfate and concentrated under reduced pressure. This liquid was subjected to column chromatography (adsorption medium: silica gel, developing solvent: n-toluene / ethyl acetate (1/1)) to remove the raw materials and high molecular weight components. This gave 5.05 g of a colorless oily substance.

This oily substance was again dissolved in 80 ml of toluene, put into a reaction vessel together with 0.72 g (10 mmol) of acrylic acid and 0.2 ml of triethylamine, and reacted at 80 ° C. for 3 hours. After standing to cool, it was washed with water and concentrated under reduced pressure. This was again added with a toluene solution and 5 g of activated clay and adsorbed at room temperature for 30 minutes, and then column chromatography (adsorption medium: silica gel, developing solvent: n-toluene / ethyl acetate (3/1)). Purified. In this way, 4.5 g of colorless oily D-1-1 was obtained. When the molecular weight of this product was measured by gel permeation chromatography, it showed a value which is a composition mainly composed of a mixture having n of 1 to 10.
As described above, other diphenol compounds can be synthesized in the same manner.

EXAMPLES Next, although an Example demonstrates this invention further in detail, this invention is not limited to a following example. Note that “parts” used in the examples all represent parts by weight.
<Example 1>
A photosensitive layer coating solution having the following composition was applied on a φ30 mm aluminum cylinder by a dipping method to form a photosensitive layer having a thickness of 23 μm after drying. A surface layer coating solution having the following composition is spray-coated on this photosensitive layer, and after natural drying for 5 minutes, a metal halide lamp: 160 W / cm, irradiation distance: 120 mm, irradiation intensity: 800 mW / cm ² , irradiation time: 60 The coating film was cured by light irradiation under the condition of seconds. Further, drying was performed at 130 ° C. for 20 minutes to provide a 2 μm surface layer, and the electrophotographic photosensitive member of the present invention was obtained.

[Photosensitive layer coating solution]
In the following formulation, a 3% solid content solution of metal-free phthalocyanine and tetrahydrofuran was ball milled with zirconia balls for 24 hours. The prepared pigment dispersion was added to a solution in which the remaining materials were mixed and dissolved to prepare a coating solution.
・ Metal-free phthalocyanine: 2 parts (FastogenBlue8120B, manufactured by Dainippon Ink & Chemicals, Inc.)
-Charge transport material of the following structural formula: 24 parts
The following diphenoquinone compound: 20 parts 2,6-dimethyl-2 ′, 6′-di-tert-butyl-diphenoquinone Bisphenol Z-type polycarbonate: 41 parts (Panlite TS-2050, manufactured by Teijin Chemicals)
Tetrahydrofuran: 382 parts Tetrahydrofuran solution of 1% silicone oil: 0.2 parts (KF50-100CS, manufactured by Shin-Etsu Chemical Co., Ltd.)

[Surface layer coating solution]
In the following formulation, all materials were mixed and dispersed in a ball mill for 48 hours to prepare a coating solution.
-Radical polymerizable compound of exemplary compound B-1-2: 20 parts-Conductive fine particle: 20 parts Antimony-doped tin oxide (T-1, manufactured by Mitsubishi Materials)
Photopolymerization initiator: 1 part 1-hydroxy-cyclohexyl-phenyl-ketone (Irgacure 184, manufactured by Ciba Specialty Chemicals)
・ Toluene: 100 parts

<Example 2>
An electrophotographic photosensitive member was produced in the same manner as in Example 1 except that the surface layer coating solution of Example 1 was changed to the following.
[Surface layer coating solution]
-Radical polymerizable compound of exemplary compound C-1-1: 20 parts-Conductive fine particles: 20 parts Antimony-doped tin oxide (T-1, manufactured by Mitsubishi Materials)
Photopolymerization initiator: 1 part 1-hydroxy-cyclohexyl-phenyl-ketone (Irgacure 184, manufactured by Ciba Specialty Chemicals)
・ Toluene: 100 parts

<Example 3>
An electrophotographic photosensitive member was produced in the same manner as in Example 1 except that the surface layer coating solution of Example 1 was changed to the following.
[Surface layer coating solution]
-Radical polymerizable compound of Exemplified Compound D-1-1: 20 parts-Conductive fine particles: 20 parts Antimony-doped tin oxide (T-1, manufactured by Mitsubishi Materials)
Photopolymerization initiator: 1 part 1-hydroxy-cyclohexyl-phenyl-ketone (Irgacure 184, manufactured by Ciba Specialty Chemicals)
・ Toluene: 100 parts

<Example 4>
By coating and drying an undercoat layer coating solution, a charge generation layer coating solution, and a charge transport layer coating solution in the following order on a φ30 mm aluminum cylinder in sequence, an undercoat layer of 3.5 μm A 0.2 μm charge generation layer and an 18 μm charge transport layer were formed. A surface layer coating solution having the following composition is spray-coated on the charge transport layer and naturally dried for 5 minutes, and then a metal halide lamp: 160 W / cm, irradiation distance: 120 mm, irradiation intensity: 800 mW / cm ² , irradiation time: The coating film was cured by light irradiation under conditions of 60 seconds. Further, drying was performed at 130 ° C. for 20 minutes to provide a 3 μm surface layer, and the electrophotographic photosensitive member of the present invention was obtained.

[Undercoat layer coating solution]
In the following formulation, all materials were mixed and ball milled with alumina balls for 48 hours. This dispersion was filtered through a 500 mesh stainless steel mesh to prepare a coating solution.
・ Alkyd resin: 6 parts (Beckolite M-6401-50, manufactured by Dainippon Ink & Chemicals, Inc.)
Melamine resin: 4 parts (Super Becamine G-821-60, manufactured by Dainippon Ink and Chemicals)
・ Titanium oxide: 40 parts ・ Methyl ethyl ketone: 50 parts

[Coating liquid for charge generation layer]
In the following formulation, a 10% solid content solution of bisazo pigment and methyl ethyl ketone was ball milled with zirconia balls for 10 days. Cyclohexanone was added to this dispersion to obtain a pigment dispersion having a solid content of 3%, and further ball milled for 2 hours. This pigment dispersion was added to a solution in which the remaining materials were mixed and dissolved, stirred well, and then filtered through a 1000 mesh stainless steel mesh to prepare a coating solution.
-Bisazo pigment with the following structure: 2.5 parts
Polyvinyl butyral (XYHL, manufactured by UCC): 0.5 part Cyclohexanone: 200 parts Methyl ethyl ketone: 80 parts

[Coating fluid for charge transport layer]
In the following formulation, all materials were mixed and dissolved to prepare a coating solution.
-Bisphenol Z-type polycarbonate: 10 parts (Panlite TS-2050, manufactured by Teijin Chemicals)
-Charge transport material with the following structural formula: 7 parts
Toluene: 100 parts Tetrahydrofuran solution of 1% silicone oil: 1 part (KF50-100CS, manufactured by Shin-Etsu Chemical Co., Ltd.)

[Surface layer coating solution]
In the following formulation, all materials were mixed and dispersed in a ball mill for 48 hours to prepare a coating solution.
-Radical polymerizable compound of Exemplified Compound B-1-1: 20 parts-Conductive fine particles: 20 parts Antimony-doped tin oxide (T-1, manufactured by Mitsubishi Materials)
Photopolymerization initiator: 1 part 1-hydroxy-cyclohexyl-phenyl-ketone (Irgacure 184, manufactured by Ciba Specialty Chemicals)
・ Toluene: 100 parts

<Example 5>
An electrophotographic photosensitive member was produced in the same manner as in Example 4 except that the surface layer coating solution of Example 4 was changed to the following.
[Surface layer coating solution]
-Radical polymerizable compound of exemplary compound C-1-1: 20 parts-Conductive fine particles: 20 parts Antimony-free tin oxide (S-1, manufactured by Mitsubishi Materials)
Photopolymerization initiator: 1 part 1-hydroxy-cyclohexyl-phenyl-ketone (Irgacure 184, manufactured by Ciba Specialty Chemicals)
Tetrahydrofuran: 100 parts

<Example 6>
An electrophotographic photosensitive member was produced in the same manner as in Example 4 except that the surface layer coating solution of Example 4 was changed to the following.
[Surface layer coating solution]
-Radical polymerizable compound of Exemplified Compound D-1-1: 20 parts-Conductive fine particles: 20 parts Antimony-doped tin oxide (T-1, manufactured by Mitsubishi Materials)
Photopolymerization initiator: 1 part 1-hydroxy-cyclohexyl-phenyl-ketone (Irgacure 184, manufactured by Ciba Specialty Chemicals)
・ Toluene: 100 parts

<Example 7>
An electrophotographic photosensitive member was produced in the same manner as in Example 4 except that the surface layer coating solution of Example 4 was changed to the following.
[Surface layer coating solution]
-Radical polymerizable compound of exemplary compound B-1-1: 10 parts-Monomer having 3 or more radical polymerizable functional groups: 10 parts Trimethylolpropane triacrylate (KAYARAD TMPTA, manufactured by Nippon Kayaku Co., Ltd.)
Conductive fine particles: 20 parts Antimony-doped tin oxide (T-1, manufactured by Mitsubishi Materials)
Photopolymerization initiator: 1 part 1-hydroxy-cyclohexyl-phenyl-ketone (Irgacure 184, manufactured by Ciba Specialty Chemicals)
・ Toluene: 100 parts

<Example 8>
An electrophotographic photosensitive member was produced in the same manner as in Example 4 except that the surface layer coating solution of Example 4 was changed to the following.
[Surface layer coating solution]
-Radical polymerizable compound of Exemplified Compound B-1-9: 10 parts-Monomer having 3 or more radical polymerizable functional groups: 10 parts Dipentaerythritol caprolactone-modified hexaacrylate (KAYARAD DPCA-120, manufactured by Nippon Kayaku)
Conductive fine particles: 20 parts Antimony-doped tin oxide (T-1, manufactured by Mitsubishi Materials)
Photopolymerization initiator: 1 part 1-hydroxy-cyclohexyl-phenyl-ketone (Irgacure 184, manufactured by Ciba Specialty Chemicals)
・ Toluene: 100 parts

<Example 9>
An electrophotographic photosensitive member was produced in the same manner as in Example 4 except that the surface layer coating solution of Example 4 was changed to the following.
[Surface layer coating solution]
-Radical polymerizable compound of Exemplified Compound B-1-2: 10 parts-Monomer having 3 or more radical polymerizable functional groups: 10 parts Dipentaerythritol caprolactone-modified hexaacrylate (KAYARAD DPCA-120, manufactured by Nippon Kayaku)
Conductive fine particles: 20 parts Antimony-doped tin oxide (T-1, manufactured by Mitsubishi Materials)
Photopolymerization initiator: 1 part 1-hydroxy-cyclohexyl-phenyl-ketone (Irgacure 184, manufactured by Ciba Specialty Chemicals)
・ Toluene: 100 parts

<Example 10>
An electrophotographic photosensitive member was produced in the same manner as in Example 4 except that the surface layer coating solution of Example 4 was changed to the following.
[Surface layer coating solution]
-Radical polymerizable compound of Exemplified Compound B-1-10: 10 parts-Monomer having 3 or more radical polymerizable functional groups: 10 parts Trimethylolpropane triacrylate (KAYARAD TMPTA, manufactured by Nippon Kayaku)
Conductive fine particles: 20 parts Antimony-doped tin oxide (T-1, manufactured by Mitsubishi Materials)
Photopolymerization initiator: 1 part 1-hydroxy-cyclohexyl-phenyl-ketone (Irgacure 184, manufactured by Ciba Specialty Chemicals)
・ Toluene: 100 parts

<Example 11>
An electrophotographic photosensitive member was produced in the same manner as in Example 4 except that the surface layer coating solution of Example 4 was changed to the following.
[Surface layer coating solution]
-Radical polymerizable compound of Exemplified Compound B-2-1: 10 parts-Monomer having 3 or more radical polymerizable functional groups: 10 parts Dipentaerythritol hexaacrylate (KAYARAD DPHA, Nippon Kayaku)
Conductive fine particles: 20 parts Antimony-doped tin oxide (T-1, manufactured by Mitsubishi Materials)
Photopolymerization initiator: 1 part 1-hydroxy-cyclohexyl-phenyl-ketone (Irgacure 184, manufactured by Ciba Specialty Chemicals)
・ Toluene: 100 parts

<Example 12>
An electrophotographic photosensitive member was produced in the same manner as in Example 4 except that the surface layer coating solution of Example 4 was changed to the following.
[Surface layer coating solution]
-Radical polymerizable compound of exemplary compound C-2-1: 10 parts-Monomer having 3 or more radical polymerizable functional groups: 10 parts Trimethylolpropane triacrylate (KAYARAD TMPTA, manufactured by Nippon Kayaku)
Conductive fine particles: 20 parts Antimony-free tin oxide (S-1, manufactured by Mitsubishi Materials)
Photopolymerization initiator: 1 part 1-hydroxy-cyclohexyl-phenyl-ketone (Irgacure 184, manufactured by Ciba Specialty Chemicals)
Tetrahydrofuran: 100 parts

<Example 13>
An electrophotographic photosensitive member was produced in the same manner as in Example 4 except that the surface layer coating solution of Example 4 was changed to the following.
[Surface layer coating solution]
-Radical polymerizable compound of exemplified compound D-1-2: 20 parts-Conductive fine particles: 20 parts Antimony-doped tin oxide (T-1, manufactured by Mitsubishi Materials)
Photopolymerization initiator: 1 part 1-hydroxy-cyclohexyl-phenyl-ketone (Irgacure 184, manufactured by Ciba Specialty Chemicals)
・ Toluene: 100 parts

<Example 14>
An electrophotographic photosensitive member was produced in the same manner as in Example 4 except that the surface layer coating solution of Example 4 was changed to the following.
[Surface layer coating solution]
-Radical polymerizable compound of exemplary compound D-1-4: 10 parts-Monomer having 3 or more radical polymerizable functional groups: 10 parts Dipentaerythritol hexaacrylate (KAYARAD DPHA, manufactured by Nippon Kayaku)
Conductive fine particles: 20 parts Antimony-free tin oxide (S-1, manufactured by Mitsubishi Materials)
Photopolymerization initiator: 1 part 1-hydroxy-cyclohexyl-phenyl-ketone (Irgacure 184, manufactured by Ciba Specialty Chemicals)
・ Toluene: 100 parts

<Comparative Example 1>
An electrophotographic photosensitive member was produced in the same manner as in Example 1 except that the surface layer coating solution of Example 1 was changed to the following.
[Surface layer coating solution]
-Radical polymerizable monomer having the following structural formula: 20 parts
Bisphenol A ethyleneoxy modified diacrylate (A-BPE-4, Shin-Nakamura Chemical Co., Ltd.)
Conductive fine particles: 20 parts Antimony-doped tin oxide (T-1, manufactured by Mitsubishi Materials)
Photopolymerization initiator: 1 part 1-hydroxy-cyclohexyl-phenyl-ketone (Irgacure 184, manufactured by Ciba Specialty Chemicals)
・ Toluene: 100 parts

<Comparative example 2>
An electrophotographic photosensitive member was produced in the same manner as in Example 4 except that the surface layer coating solution of Example 4 was changed to the following.
[Surface coating liquid]
-Radical polymerizable monomer: 20 parts Bisphenol A ethyleneoxy modified diacrylate (ABE-300, Shin-Nakamura Chemical Co., Ltd.)
Conductive fine particles: 20 parts Antimony-doped tin oxide (T-1, manufactured by Mitsubishi Materials)
Photopolymerization initiator: 1 part 1-hydroxy-cyclohexyl-phenyl-ketone (Irgacure 184, manufactured by Ciba Specialty Chemicals)
・ Toluene: 100 parts

<Comparative Example 3>
An electrophotographic photosensitive member was produced in the same manner as in Example 4 except that the surface layer coating solution of Example 4 was changed to the following.
[Surface layer coating solution]
-Radical polymerizable monomer: 10 parts Bisphenol A ethyleneoxy modified diacrylate (ABE-300, Shin-Nakamura Chemical Co., Ltd.)
-Monomer having 3 or more radical polymerizable functional groups: 10 parts Trimethylolpropane triacrylate (KAYARAD TMPTA, Nippon Kayaku)
Conductive fine particles: 20 parts Antimony-doped tin oxide (T-1, manufactured by Mitsubishi Materials)
Photopolymerization initiator: 1 part 1-hydroxy-cyclohexyl-phenyl-ketone (Irgacure 184, manufactured by Ciba Specialty Chemicals)
・ Toluene: 100 parts

<Comparative example 4>
An electrophotographic photosensitive member was produced in the same manner as in Example 4 except that the surface layer coating solution of Example 4 was changed to the following.
[Surface layer coating solution]
・ Radically polymerizable monomer of the following structural formula: 20 parts (KAYARAD SR-230, manufactured by Nippon Kayaku)
Conductive fine particles: 20 parts Antimony-doped tin oxide (T-1, manufactured by Mitsubishi Materials)
Photopolymerization initiator: 1 part 1-hydroxy-cyclohexyl-phenyl-ketone (Irgacure 184, manufactured by Ciba Specialty Chemicals)
・ Toluene: 100 parts

<Comparative Example 5>
An electrophotographic photosensitive member was produced in the same manner as in Example 4 except that the surface layer coating solution of Example 4 was changed to the following.
[Surface layer coating solution]
・ Radically polymerizable monomer: 20 parts Dipentaerythritol hexaacrylate (KAYARAD DPHA, Nippon Kayaku)
Conductive fine particles: 20 parts Antimony-doped tin oxide (T-1, manufactured by Mitsubishi Materials)
Photopolymerization initiator: 1 part 1-hydroxy-cyclohexyl-phenyl-ketone (Irgacure 184, manufactured by Ciba Specialty Chemicals)
・ Toluene: 100 parts

<Comparative Example 6>
An electrophotographic photosensitive member was produced in the same manner as in Example 4 except that the surface layer coating solution of Example 4 was changed to the following.
[Surface layer coating solution]
-Monomer having 3 or more radical polymerizable functional groups: 10 parts Trimethylolpropane triacrylate (KAYARAD TMPTA, Nippon Kayaku)
Conductive fine particles: 20 parts Antimony-doped tin oxide (T-1, manufactured by Mitsubishi Materials)
Photopolymerization initiator: 1 part 1-hydroxy-cyclohexyl-phenyl-ketone (Irgacure 184, manufactured by Ciba Specialty Chemicals)
・ Toluene: 100 parts

<Comparative Example 7>
An electrophotographic photosensitive member was produced in the same manner as in Example 4 except that the surface layer coating solution of Example 4 was changed to the following.
[Surface layer coating solution]
-Monomer having 3 or more radical polymerizable functional groups: 10 parts Ethoxylated trimethylolpropane triacrylate (KAYARAD SR-415, manufactured by Nippon Kayaku)
Conductive fine particles: 20 parts Antimony-doped tin oxide (T-1, manufactured by Mitsubishi Materials)
Photopolymerization initiator: 1 part 1-hydroxy-cyclohexyl-phenyl-ketone (Irgacure 184, manufactured by Ciba Specialty Chemicals)
・ Toluene: 100 parts

The photoconductors of Examples 1 to 14 and Comparative Examples 1 to 7 manufactured as described above were subjected to a paper passing test (normal temperature and normal humidity) of 75,000 sheets of A4 size using a modified Imagio MF2200. did.
Imagio MF2200 remodeling machine: The charging part is a fixed charging method shown in FIG. 3 (IV). (Charging member: Toho Rayon FW210, Inoac Corporation SP-80)
First, the photosensitive member was mounted on a process cartridge for an electrophotographic apparatus, and an initial dark portion potential was set to −700 V using a 655 nm semiconductor laser as an image exposure light source. Thereafter, a paper passing test was started. Image evaluation after copying the initial and 75,000 sheets, the amount of wear of the electrophotographic photosensitive member (the value obtained by subtracting the initial photosensitive member film thickness from the photosensitive member film thickness after completion of the paper passing test) The film thickness was measured using a Fischerscope MMS Fischer). The results are shown in Table 3 below.

  As described above, the photoconductor of the present embodiment has much less wear and excellent wear resistance, and a good image can be obtained continuously. In Comparative Examples 1 to 3, as a result of using bisphenol A type diacrylate as a monomer, the amount of wear was larger than that of the photoreceptor of this example. In Comparative Examples 5 to 6 using a tri- or higher functional monomer, high wear resistance was obtained in terms of the number of functional groups, but white spots were generated in the image. This seems to be due to the occurrence of minute cracks generated on the surface of the photoreceptor. The photoreceptor using the bifunctional monomer of Comparative Example 4 had a large amount of wear. Therefore, it can be seen that the photoconductor of this example is generally superior to the photoconductor of the comparative example.

Next, a crack acceleration test of the photosensitive layer was performed on the photoreceptors of Examples 1 to 3 and Comparative Examples 5 to 7. The results are shown in Table 4. As an evaluation method, finger oil was attached to the surface of the electrophotographic photosensitive member, and left for 3 days at 50 ° C. and normal pressure, and then the surface state of the photosensitive layer was observed.
As described above, the photoreceptor of this example has excellent durability even in the crack acceleration test. This is because, in the photoconductors of Comparative Examples 5, 6, and 7, when only a trifunctional or higher functional acrylic monomer is used, the shrinkage ratio of the film during curing is high.

Next, the photoreceptors of Examples 1 to 3 and Comparative Examples 1 to 3 were subjected to a NOx exposure test using Direc (DY-0102N). Under NOx Environment _{(NO: 40ppm, NO 2:} 10ppm) was allowed to stand at 96 hours, an image density difference of NOx before and after exposure of the halftone image. An X-lite spectral densitometer 508 was used for image density measurement. The difference in image density is (image density after NOx exposure) − (image density before NOx exposure). The results are shown in the table below.
As described above, the image density change is large in the photoreceptors using the bisphenol A structure monomers of Comparative Examples 1, 2, and 3. On the other hand, the photoconductor of this embodiment has excellent durability against NOx gas. This is because the adsorption of the oxidizing gas to the oxygen atom, which is a polar group, is suppressed by replacing the hydrogen of the benzene nucleus with a bulky substituent.

  From the above, the electrophotographic photosensitive member containing the radical curable composition containing the structure of the general formula (A) shown in Examples 1 to 14 is excellent in film strength, gas resistance, and generation of cracks. It turns out that it has image output stability.

An example of the layer structure of the electrophotographic photoreceptor is shown. Another example of the layer structure of the electrophotographic photoreceptor is shown. An example of a contact charging method is shown. 1 shows an example of an electrophotographic process cartridge. It is an infrared absorption spectrum of the compound obtained by the synthesis example of exemplary compound B-1-1 used for this invention. It is an infrared absorption spectrum of the compound obtained by the synthesis example of exemplary compound C-1-1 used for this invention. It is an infrared absorption spectrum of the compound obtained by the synthesis example of exemplary compound D-1-1 used for this invention.

Explanation of symbols

11 Electrophotographic photoreceptor 12 Charging device 13 Image exposure 14 Developing roller 15 Transfer member 16 Transfer roller 17 Cleaning unit 18 Gradual lamp 19 Fixing unit

Claims (9)

An electrophotographic photosensitive member, wherein the electrophotographic photosensitive member includes at least a charging member, an exposing unit, a developing unit, and a transferring unit that are disposed in contact with the electrophotographic photosensitive member and charge the electrophotographic photosensitive member by applying a voltage. The photographic photoreceptor has a photosensitive layer that is not radically cured, and a surface layer that contains the radically cured composition and conductive fine particles, and the radically cured composition has at least a structural unit represented by the following general formula (A) And an electrophotographic apparatus characterized in that the charging is injection charging.
(Expressed in the _{formula, R 5, R 6, R} 7 and R ₈ are each a hydrogen atom, a linear or branched or cyclic alkyl group having 1 to 6 carbon atoms, an allyl group, a halogen atom, an aryl group, R ₉ And R ₁₀ represents a hydrogen atom, a methyl group, or an ethyl group, except that all of R _{5 to} R ₈ are hydrogen atoms, and the sum of the carbon number of R _{9 and} the carbon number of R ₁₀ is 0 to 2. is there.) After the surface layer of the electrophotographic photoreceptor is coated with a coating solution containing at least conductive fine particles and a radical polymerizable compound represented by the following general formula (B) on the surface of the photosensitive layer to form a coating film 2. The electrophotographic apparatus according to claim 1, wherein the electrophotographic apparatus is formed by radical curing of a radical polymerizable compound in the coating film.
(In the formula, R ₁ and R ₂ each represent a linear or branched alkylene group having 1 to 6 carbon atoms, 1-ketohexylene group, R ₃ and R ₄ represent a hydrogen atom or a methyl group, R ₅ , R ₆ , R ₇ and R ₈ each represent a hydrogen atom, a linear, branched or cyclic alkyl group having 1 to 6 carbon atoms, an allyl group, a halogen atom or an aryl group, and R ₉ and R ₁₀ are hydrogen atoms. Represents an atom, a methyl group, or an ethyl group, and n to m each represents an integer of 0 to 4, except when all of R _{5 to} R ₈ are hydrogen atoms, the number of carbons of R _{9 and} the carbon number of R ₁₀ The sum of the numbers is 0-2.) After the surface layer of the electrophotographic photoreceptor is coated with a coating solution containing at least conductive fine particles and a radical polymerizable compound represented by the following general formula (C) on the surface of the photosensitive layer to form a coating film 2. The electrophotographic apparatus according to claim 1, wherein the electrophotographic apparatus is formed by radical curing of a radical polymerizable compound in the coating film.
(In the formula, R ₁₁ , R ₁₂ , R ₁₃ and R ₁₄ each represent a hydrogen atom or a methyl group, and R ₅ , R ₆ , R ₇ and R ₈ are each a hydrogen atom and a straight chain having 1 to 6 carbon atoms. Or a branched or cyclic alkyl group, an allyl group, a halogen atom, or an aryl group, and R ₉ and R ₁₀ represent a hydrogen atom, a methyl group, or an ethyl group, provided that all of R _{5 to} R ₈ are hydrogen atoms. (The sum of the carbon number of R _{9 and} the carbon number of R ₁₀ is 0 to 2.) After the surface layer of the electrophotographic photoreceptor is coated with a coating solution containing at least conductive fine particles and a radical polymerizable compound represented by the following general formula (D) on the surface of the photosensitive layer to form a coating film 2. The electrophotographic apparatus according to claim 1, wherein the electrophotographic apparatus is formed by radical curing of a radical polymerizable compound in the coating film.
(Wherein R ₂₁ and R ₂₂ each represent a hydrogen atom or a methyl group, and R ₅ , R ₆ , R ₇ and R ₈ are each a hydrogen atom, a linear, branched or cyclic alkyl having 1 to 6 carbon atoms. A group, an allyl group, a halogen atom, and an aryl group, R ₉ and R ₁₀ represent a hydrogen atom, a methyl group, and an ethyl group, and n represents an integer of 1 to 50, provided that all of R _{5 to} R ₈ are hydrogen. (When it is an atom, the sum of the carbon number of R _{9 and} the carbon number of R ₁₀ is 0 to 2.) Surface layer of the electrophotographic photosensitive member, three at least conductive fine particles and the following general formula (B), and either (C), a radical polymerizable compound represented by (D), a further radical polymerizable functional group By coating the surface of the photosensitive layer with a coating solution containing the monomer having the above, a coating film is formed, and the monomer having three or more radically polymerizable compounds and radically polymerizable functional groups in the coating film is radically cured. The electrophotographic apparatus according to claim 1, wherein the electrophotographic apparatus is formed.
(In the formula, R ₁ and R ₂ each represent a linear or branched alkylene group having 1 to 6 carbon atoms, 1-ketohexylene group, R ₃ and R ₄ represent a hydrogen atom or a methyl group, R ₅ , R ₆ , R ₇ and R ₈ each represent a hydrogen atom, a linear, branched or cyclic alkyl group having 1 to 6 carbon atoms, an allyl group, a halogen atom or an aryl group, and R ₉ and R ₁₀ are hydrogen atoms. atom, a methyl group, an ethyl group, n to m represents an integer of 0 to 4. However carbon carbon number and R ₁₀ of the .R ₉ except when all R ₅ to R ₈ is a hydrogen atom The sum of the numbers is 0-2.)
(In the formula, R ₁₁ , R ₁₂ , R ₁₃ and R ₁₄ each represent a hydrogen atom or a methyl group, and R ₅ , R ₆ , R ₇ and R ₈ are each a hydrogen atom and a straight chain having 1 to 6 carbon atoms. Or a branched or cyclic alkyl group, an allyl group, a halogen atom, or an aryl group, and R ₉ and R ₁₀ represent a hydrogen atom, a methyl group, or an ethyl group, provided that all of R _{5 to} R ₈ are hydrogen atoms. ( The sum of the carbon number of R _{9 and} the carbon number of R ₁₀ is 0 to 2.)
(Wherein R ₂₁ and R ₂₂ each represent a hydrogen atom or a methyl group, and R ₅ , R ₆ , R ₇ and R ₈ are each a hydrogen atom, a linear, branched or cyclic alkyl having 1 to 6 carbon atoms. A group, an allyl group, a halogen atom, and an aryl group, R ₉ and R ₁₀ represent a hydrogen atom, a methyl group, and an ethyl group, and n represents an integer of 1 to 50, provided that all of R _{5 to} R ₈ are hydrogen. (When it is an atom, the sum of the carbon number of R _{9 and} the carbon number of R ₁₀ is 0 to 2.)   6. The electrophotographic apparatus according to claim 1, wherein the surface layer of the electrophotographic photosensitive member is cured by means using light energy.   The electrophotographic apparatus according to claim 1, wherein the conductive fine particles are a metal oxide.   The photosensitive layer of the electrophotographic photosensitive member that is not radically cured has a structure in which at least a charge generation layer and a charge transport layer are sequentially laminated on a conductive support. The electrophotographic apparatus according to the description.   9. A process cartridge used in the electrophotographic apparatus according to claim 1, wherein the process cartridge is selected from an electrophotographic photosensitive member, and further a charging unit, an exposing unit, a developing unit, a transferring unit, a cleaning unit, and a neutralizing unit. A process cartridge comprising at least one means and being detachable from an electrophotographic apparatus.