JP2009216859A - Method for manufacturing electrophotographic photoreceptor, electrophotographic photoreceptor, image forming method, image forming apparatus, process cartridge for image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing an electrophotographic photoreceptor which provides an excellent durability, prevents a decrease in electric characteristics, and achieves high-quality image formation for a long period of time by controlling a temperature when forming a crosslinked surface layer by irradiation with UV rays, to provide an electrophotographic photoreceptor having a long life time and high performance manufactured by the method, and also to provide an image forming method, an image forming apparatus and a process cartridge for an image forming apparatus, using the photoreceptor. <P>SOLUTION: The method for manufacturing the electrophotographic photoreceptor having a photosensitive layer and a surface layer on a conductive support body includes a step of forming the surface layer comprising a crosslinked resin film cured by irradiation with UV rays, wherein the temperature is controlled in such a manner that a temperature rise on the photoreceptor surface is not less than 10°C from starting irradiation to 30 seconds after upon irradiating with UV rays, and that the attained temperature of the photoreceptor surface when the irradiation is completed is 40 to 60°C. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a method for manufacturing an electrophotographic photosensitive member, an electrophotographic photosensitive member manufactured by the manufacturing method, an image forming method using the same, an image forming apparatus, and a process cartridge for the image forming apparatus.

  In recent years, organic photoreceptors (OPC) have been widely used in copying machines, facsimile machines, laser printers, and composite machines in place of inorganic photoreceptors because of their good performance and various advantages. This is because, for example, (1) optical characteristics such as the light absorption wavelength range and the amount of absorption, (2) electrical characteristics such as high sensitivity and stable charging characteristics, and (3) material selection range (4) Ease of manufacturing, (5) Low cost, (6) Non-toxicity, and the like.

On the other hand, the diameter of the photoconductor has recently been reduced due to the downsizing of the image forming apparatus, and the high speed of the machine and the maintenance-free movement have been added to increase the durability of the photoconductor. From this point of view, organophotoreceptors are generally soft because the surface layer is mainly composed of low-molecular charge transport materials and inert polymers, and when used repeatedly in electrophotographic processes, they are mechanically driven by development systems and cleaning systems. There is a drawback that wear is likely to occur due to a typical load. In addition, due to the demand for higher image quality, the cleaning blade has to be increased in hardness and contact pressure for the purpose of improving the cleaning properties as the particle size of the toner particles is reduced. This also promotes the wear of the photoreceptor. It is a factor. Such abrasion of the photoreceptor deteriorates electrical characteristics such as sensitivity deterioration and chargeability, and causes abnormal images such as image density reduction and background stains. Further, scratches where wear is locally generated cause streak-like stain images due to poor cleaning. Under the present circumstances, the wear and scratches are rate-determined and the life of the photoconductor has been replaced.
Therefore, it is indispensable to reduce the above-mentioned wear amount in order to increase the durability of the organic photoreceptor, and this is the most pressing issue in this field.

  Techniques for improving the abrasion resistance of the photosensitive layer include (1) using a curable binder for the surface layer (see, for example, Patent Document 1), and (2) using a polymeric charge transport material ( For example, refer patent document 2), (3) what dispersed the inorganic filler in the surface layer (for example, refer patent document 3), etc. are mentioned. Among these techniques, those using the curable binder (1) have poor compatibility with the charge transport material, and the residual potential increases due to impurities such as polymerization initiators and unreacted residues, resulting in a decrease in image density. Tends to occur. In addition, (2) using a polymer type charge transport material and (3) dispersed inorganic filler are required for organic photoreceptors, although they can improve wear resistance to some extent. The durability has not been fully satisfied. Further, in the case where the inorganic filler (3) is dispersed, the residual potential increases due to traps present on the surface of the inorganic filler, and the image density tends to decrease. These technologies (1), (2), and (3) are sufficient to satisfy the overall durability including the electrical durability and mechanical durability required for the organic photoreceptor. Has not reached.

As an alternative to the wear resistance technology of the photosensitive layer, a charge transport layer formed by using a coating liquid comprising a monomer having a carbon-carbon double bond, a charge transport material having a carbon-carbon double bond, and a binder resin is used. It is known to provide (for example, refer to Patent Document 4). In particular, the surface layer is a cross-linked resin layer obtained by curing a radical polymerizable compound having at least a trifunctional radical polymerizable monomer not having a charge transport structure and a radical polymerizable compound having a charge transport structure by ultraviolet irradiation, thereby improving wear resistance and Electrical characteristics are remarkably improved (see, for example, Patent Document 5, Patent Document 6, and Patent Document 7).
In forming a crosslinked resin layer using such a polymerizable compound, ultraviolet rays or electron beams are often used as a driving force for the crosslinking reaction. In the cross-linking reaction by ultraviolet ray or electron beam irradiation, in addition to the energy of ultraviolet ray or electron beam, the influence of the reaction temperature at the time of irradiation is great, and the characteristics vary greatly depending on the temperature conditions (see, for example, Patent Document 8 and Patent Document 9). In Patent Document 8 using ultraviolet irradiation, the temperature reached by the substrate at the time of ultraviolet irradiation is set to a high temperature of 70 ° C. or more and 90 ° C. or less, thereby promoting the crosslinking reaction and improving the hardness characteristics even in the low energy amount of ultraviolet irradiation. ing. However, it has been found that the substrate temperature at the time of ultraviolet irradiation greatly affects the electrical characteristics of the photoreceptor. Even if the amount of UV irradiation is appropriate, if the temperature is too high, or if the temperature rise in the initial stage at the start of irradiation is small, the electrical characteristics will deteriorate, and the image density will decrease due to long-term use. There is. From the above, it cannot be said that the method for producing a crosslinked surface layer by ultraviolet irradiation in the prior art sufficiently satisfies long-term durability and electrical stability.

JP 56-48637 A JP-A 64-1728 JP-A-4-281461 Japanese Patent No. 3194392 JP 2004-302450 A JP 2004-302451 A JP 2004-302452 A JP 2007-279288 A JP 2006-195497 A

  The object of the present invention is to control the temperature when forming a crosslinked surface layer by ultraviolet irradiation, thereby providing excellent durability, and at the same time preventing deterioration of electrical characteristics and high-quality image formation over a long period of time. The object is to provide a method for producing the realized electrophotographic photosensitive member. Another object of the present invention is to provide a long-life, high-performance electrophotographic photosensitive member manufactured by these manufacturing methods, an image forming method using the same, an image forming apparatus, and a process cartridge for the image forming apparatus. The point is to provide.

  In the method for producing an electrophotographic photosensitive member having a photosensitive layer and a surface layer on a conductive support, the inventors of the surface layer are cured by irradiating ultraviolet rays to form a crosslinked resin film. And a temperature rise of the photoreceptor surface from 30 to 30 seconds after the start of irradiation at the time of ultraviolet irradiation is 10 ° C. or more, and the temperature reached on the photoreceptor surface at the end of irradiation is 40 ° C. or more and 60 ° C. or less. The present invention has been completed by discovering that the above problems can be achieved by a method for producing an electrophotographic photosensitive member characterized by controlling the temperature.

That is, the said subject is solved by the following this invention.
(1) “In the method for producing an electrophotographic photoreceptor having a photosensitive layer and a surface layer on a conductive support, the surface layer is formed by curing the surface layer by irradiating with ultraviolet rays to form a crosslinked resin film” The temperature rise of the photoreceptor surface from the start of irradiation at the time of ultraviolet irradiation to 30 seconds is 10 ° C. or more, and the temperature reached on the photoreceptor surface at the end of irradiation is controlled to 40 ° C. or more and 60 ° C. or less. A method for producing an electrophotographic photosensitive member, ”
(2) "the first (1) The method for producing an electrophotographic photosensitive member according to claim irradiation amount of the ultraviolet rays, characterized in that it is 70 J / cm ² or more 120 J / cm ² or less",
(3) “The method for producing an electrophotographic photoreceptor according to (1) or (2) above, wherein an initial temperature of the surface of the photoreceptor before ultraviolet irradiation is 30 ° C. or less”,
(4) "The conductive support is a cylindrical base, and has a cylindrical elastic body that contacts the entire inner surface of the cylindrical base as temperature control means for temperature control, and the cylindrical elastic Any of (1) to (3) above, characterized in that a temperature control device is used for controlling the temperature by introducing a liquid as a refrigerant into the body and suppressing the temperature rise of the cylindrical substrate. The method for producing the electrophotographic photoreceptor according to the above ",
(5) The electrophotographic photosensitive member as described in (4) above, wherein the cylindrical elastic body is swelled by the pressure of a liquid used as a refrigerant and is in close contact with the inner surface of the cylindrical substrate. Body manufacturing method ",
(6) "The method for producing an electrophotographic photosensitive member according to (4) or (5) above, wherein the thickness of the cylindrical elastic body is from 0.5 mm to 3.0 mm",
(7) “The crosslinked resin film is
(B) Cured and formed by irradiating ultraviolet rays onto a monomer mixture containing a tri- or higher functional radical polymerizable monomer having no charge transport structure and (b) a radical polymerizable compound having a charge transport structure. The method for producing an electrophotographic photosensitive member according to any one of the items (1) to (6),
(8) "Electrophotographic photosensitive member produced using the method for producing an electrophotographic photosensitive member according to any one of (1) to (7)",
(9) "An image forming method characterized in that at least charging, image exposure, development, and transfer are repeatedly performed using the electrophotographic photosensitive member according to (8) above",
(10) "Image forming apparatus comprising the electrophotographic photosensitive member according to item (8)",
(11) “having at least one means selected from the group consisting of the electrophotographic photosensitive member according to the above (8) and a charging means, a developing means, a transfer means, a cleaning means, and a static elimination means, An image forming apparatus process cartridge characterized by being detachable from the main body of the image forming apparatus.

  In the method for producing an electrophotographic photosensitive member having a photosensitive layer and a surface layer on a conductive support according to the present invention, the step of forming the surface layer, wherein the surface layer is cured by irradiation with ultraviolet rays to form a crosslinked resin film The temperature rise of the photoreceptor surface from the start of irradiation at the time of ultraviolet irradiation to 30 seconds is 10 ° C. or more, and the temperature reached on the photoreceptor surface at the end of irradiation is controlled to 40 ° C. or more and 60 ° C. or less. By the electrophotographic photosensitive member manufacturing method characterized in that, an electrophotographic photosensitive member having excellent durability and stable electrical characteristics and capable of maintaining a high-quality image is realized. In addition, the photoconductor manufactured by the manufacturing method of the present invention, the image forming process using the photoconductor, the image forming apparatus, and the process cartridge for the image forming apparatus have high performance and high reliability.

The present invention is based on the following basic idea.
The method for producing an electrophotographic photosensitive member of the present invention relates to a method for producing a surface layer formed by ultraviolet irradiation. The surface layer formed by the ultraviolet irradiation can form a three-dimensional crosslinked surface layer, which can dramatically improve the wear resistance of the electrophotographic photosensitive member.
Higher wear resistance can be obtained by using a surface layer obtained by curing a mixture of a tri- or higher functional radical polymerizable monomer having no charge transport structure and a radical polymerizable compound having a charge transport structure as a constituent material of the crosslinked surface layer. An electrophotographic photosensitive member having high performance and stable electric characteristics is achieved. By using a radically polymerizable trifunctional or higher functional monomer having no charge transporting structure and curing reaction by ultraviolet irradiation, a three-dimensional network structure is developed, and a highly hard crosslinked surface layer having a very high crosslinking density is obtained. High wear resistance is achieved. Moreover, in addition to the trifunctional or higher functional radical polymerizable monomer having no charge transporting structure, it contains a radical polymerizable compound having a charge transporting structure, so that these are simultaneously polymerized and cured in a short time, and have high hardness. By forming a cross-linked bond and improving the durability and having a charge transporting structure, better electrical characteristics can be achieved. Furthermore, by curing a radically polymerizable monomer having a large number of reactive functional groups and a fast curing speed and having no charge transporting structure and having a trifunctional or higher functionality and a radically polymerizable compound having a charge transporting structure, It is possible to form a uniform crosslinked film with little distortion, and as a result, the unreacted portion of the charge transport material is reduced in the crosslinked surface layer, and the homogeneity inside the crosslinked film is greatly improved. As a result, it is possible to achieve both an improvement in wear resistance and a stable electrostatic property and an electrophotographic photoreceptor free from cracks.

  In the present invention, the photoconductor is not only naturally cooled from the surface side, but is also cooled in a controlled manner from the inner side of the conductive substrate having higher thermal conductivity (heat dissipation). The surface layer formed by ultraviolet irradiation can form a three-dimensional crosslinked surface layer, and can dramatically improve the wear resistance of the electrophotographic photosensitive member. However, such a cross-linked surface layer by ultraviolet irradiation causes poor curing and deterioration of electrical characteristics due to high temperature when the substrate temperature at the time of ultraviolet irradiation is not appropriate. As a result of an arbitrary study by the present inventors, the temperature rise of the photoreceptor surface from the start of irradiation at the time of ultraviolet irradiation to 30 seconds is set to 10 ° C. or higher, and the reached temperature at the end of irradiation is 40 ° C. or higher to 60 ° C. It has been found that an electrophotographic photoreceptor having sufficient curing and good electrical properties can be produced by the following. By increasing the temperature of the surface of the photoreceptor from 30 ° C. to 30 ° C. from the start of irradiation with UV irradiation, increasing the temperature rising rate at the start of irradiation, and setting the temperature reached at the end of UV irradiation to 60 ° C. or less, Curing at a low temperature can be completed in a short time, and deterioration of the charge transport material due to ultraviolet irradiation at a high temperature can be suppressed. On the other hand, when the ultimate temperature is less than 40 ° C., the curing reaction becomes insufficient due to the low temperature, the abrasion resistance becomes insufficient, and the unreacted residue becomes a charge trap, causing deterioration of electrical characteristics. The ultimate temperature at the end of ultraviolet irradiation is more preferably 45 ° C. or higher and 55 ° C. or lower.

The production method of the present invention will be described in detail below.
When the surface of the photoconductor is irradiated with ultraviolet rays, the surface temperature of the photoconductor rapidly increases due to the radiation heat of the ultraviolet rays. At this time, the surface temperature of the photoreceptor usually has a temperature profile as shown in FIG. In the present invention, the temperature rise from the start of ultraviolet irradiation to 30 seconds is 10 ° C. or higher, and the ultimate temperature at the end of the ultraviolet irradiation is 40 ° C. or higher and 60 ° C. or lower. As shown in FIG. The start temperature refers to the surface temperature of the photoreceptor at the start of ultraviolet irradiation, and the reached temperature refers to the surface temperature of the photoreceptor at the end of ultraviolet irradiation.
Moreover, it is preferable that the starting temperature at the time of ultraviolet irradiation is 30 degrees C or less. When the temperature is higher than 30 ° C., surface shrinkage may occur in the initial stage of the curing reaction, and wrinkles may occur on the surface of the crosslinked film.

In order to form the temperature profile (B in FIG. 1) of the present invention, it is necessary to control the temperature of the photosensitive member during ultraviolet irradiation. The temperature control method of the present invention will be described below. In the formation of the crosslinked surface layer by the ultraviolet irradiation of the present invention, the surface temperature of the photosensitive member is increased by the radiant heat from the ultraviolet lamp, and therefore it is necessary to control the temperature of the support during the ultraviolet irradiation. The temperature control method may be any method as long as the temperature range is within the range of the present invention. In the present invention, among various possible temperature control means candidates, in particular, adjustment of the mode of ultraviolet irradiation from the UV lamp. And adjusting the temperature within the target temperature range accurately and effectively by combining with the adjustment of the cooling mode of the support. Furthermore, as a preferable adjustment means for the cooling mode of the support, a cylindrical base is used as the support, and a coolant is used from the inside of the cylindrical base to suppress the temperature rise of the cylindrical base, so that the target temperature is reached. It includes performing temperature control using a temperature control device characterized by being controllable. There is also a method of controlling the temperature by suppressing the temperature rise from the outside of the cylindrical base body, but when performing temperature control from the outside, it is necessary to use a gas as a refrigerant, so the temperature reached at the time of ultraviolet irradiation is controlled to 60 ° C. or less It is difficult to do. In addition, in the case of cooling with gas, uniform temperature control in the axial direction and circumferential direction of the cylindrical substrate is difficult, and uneven curing may occur.
A conceptual diagram of an example of a temperature control device used in the present invention is shown in FIG.

As shown in FIG. 2, an ultraviolet lamp (52) is disposed in the vicinity of the cylindrical base (51), and is placed inside the cylindrical base (51) rotating while receiving heat from the ultraviolet lamp (52). And a cylindrical elastic body (54) in contact with the entire inner surface of the cylindrical base body (51), and an axial center of the cylindrical base body (51) inside the cylindrical elastic body (54). A coaxial refrigerant supply pipe (59) is provided, and the refrigerant is discharged from the upper end of the refrigerant supply pipe (59). The cylindrical elastic body (54) swells due to the pressure of the liquid used as the refrigerant, adheres closely to the inner surface of the cylindrical base, holds the cylindrical base, and controls the temperature of the cylindrical base. Further, by providing a refrigerant supply pipe (59) and extending the upper part of the cylindrical elastic body (51), the temperature of the refrigerant inside the cylindrical elastic body is made uniform, and the temperature of the cylindrical base body (51) is made uniform. can do. In the temperature control apparatus shown in FIG. 2, the temperature can be controlled without wetting the cylindrical substrate (51) by indirectly contacting the liquid used as the refrigerant with the cylindrical substrate (51).
The liquid used as the refrigerant of the temperature control device is preferably supplied from a constant temperature water layer in order to accurately control the temperature.

  By setting the pressure of the refrigerant supplied to the cylindrical elastic body to 0.01 Mpa to 0.2 Mpa, preferably 0.02 Mpa to 0.15 Mpa, the inner surface of the cylindrical base body (51) and the cylindrical elastic body (54) The outer surface can be in close contact, and the temperature variation of the cylindrical substrate (51) can be reduced. When the pressure of the refrigerant is smaller than 0.01 Mpa, the amount of swelling of the cylindrical elastic body (54) is reduced, and a partial gap is generated on the inner surface of the cylindrical base body (51), resulting in temperature variations of the cylindrical base body. To do. When the pressure of the refrigerant is 0.2 Mpa or more, the roundness of the cylindrical base body decreases, and the amount of swelling at the upper and lower ends of the cylindrical elastic body (54) protruding from the upper and lower sides of the cylindrical base body (51) increases. The cylindrical elastic body (54) bursts.

  The refrigerant is preferably circulated by a circulation pump of the refrigerant, and the circulation flow rate is preferably 2 L / min or more. By setting the circulation flow rate to 2 L / min or more, heat exchange necessary for making the temperature of the cylindrical substrate uniform can be performed. If the circulating flow rate is less than 2 L / min, a temperature difference occurs in the refrigerant inside the cylindrical elastic body, and uniform temperature control cannot be performed.

The cylindrical elastic body that contacts the entire inner surface of the cylindrical base of the temperature control device is preferably excellent in heat resistance, water resistance, and elasticity. Moreover, in order to improve the adhesiveness between the cylindrical elastic body and the cylindrical base body, it is preferable that the surface of the cylindrical elastic body has few irregularities. The cylindrical elastic body may have any thermal conductivity, but is preferably 0.1 W / (m · K) to 5 W / (m · K). When the thermal conductivity is less than 0.1 W / (m · K), the temperature tends to increase, and it becomes difficult to control the temperature reached at the time of ultraviolet irradiation to 60 ° C. or less. In addition, when the thermal conductivity is greater than 5 W / (m · K), it becomes difficult to increase the temperature after 30 seconds from the start of UV irradiation to 10 ° C. or higher, and the ultimate temperature is set to 40 ° C. or higher. Can be difficult. However, even when the thermal conductivity is outside the above range, the temperature rise and the arrival temperature at the start of ultraviolet irradiation can be controlled by the temperature of the refrigerant and the thickness of the cylindrical elastic body. In the present invention, a seamless cylindrical elastic body made of ethylene propylene diene rubber (EPDM, thermal conductivity 0.36 W / (m · K)) manufactured by Maruyoshi Polymer Co., Ltd. is used.
The thickness of the cylindrical elastic body is preferably 0.5 mm to 3.0 mm, and more preferably 0.8 mm to 1.5 mm. When the thickness of the cylindrical elastic body (54) is less than 0.5 mm, the durability is remarkably deteriorated, and the replacement cycle of the cylindrical elastic body (54) is shortened. When the thickness of the cylindrical elastic body (54) exceeds 3.0 mm, heat transfer from the cylindrical base body (51) to the refrigerant supplied to the inside of the cylindrical elastic body (54) becomes worse, and the temperature rise is controlled. It may be difficult to do this, and the uniformity of temperature in the base axis direction may be reduced.
The cylindrical substrate (51) is irradiated with ultraviolet rays while rotating. The rotational speed of the cylindrical substrate is preferably 10 rpm or more, and more preferably 20 rpm or more. When it is less than 10 rpm, the irradiation of ultraviolet rays becomes non-uniform, which may cause poor curing or uneven curing.

  The method for measuring the surface temperature of the photoreceptor in the present invention may be any method, such as a contact thermocouple, a non-contact thermocouple, an infrared radiation thermometer, a liquid column thermometer, and a bimetal thermometer. There is a measurement method. In the present invention, the measurement is performed by using a cylindrical substrate and bringing a contact-type thermocouple into contact with the surface of the photoreceptor from the non-irradiated side of the photoreceptor irradiated with ultraviolet rays. A multimeter PC520M and a K-type thermocouple are used.

For the ultraviolet irradiation lamp of the present invention, a high-pressure mercury lamp, a metal halide lamp, or the like can be used. The illuminance of the ultraviolet ray of the present invention indicates the illuminance on the surface of the photosensitive member. In the present invention, an illuminance at 365 nm is measured using an integrated UV light meter UIT-150-A and measurement probe UVD-S365 manufactured by USHIO. ing. Illuminance of ultraviolet is preferably 500 mW / cm ² or more 1000 mW / cm ² or less, more preferably 700 mW / cm ² or more 900 mW / cm ² or less. When the illuminance is smaller than 500 mW / cm ² , the curing reaction is insufficient and sufficient wear resistance may not be obtained. When the illuminance exceeds 1000 mW / cm ² , the curing reaction may proceed non-uniformly and unevenness may occur on the crosslinked film surface.

The dose of the present invention is the product of the time of irradiating ultraviolet rays to the photoreceptor and the illuminance, in the present invention, preferably 70 J / cm ² or more 120 J / cm ² or less, 80 J / cm ² or more 110J / cm ² or less Is more preferable. When it is lower than 70 J / cm ^2, curing is insufficient and sufficient wear resistance cannot be ensured. Furthermore, unreacted residues may act as charge traps and cause an increase in residual potential. On the other hand, when it is larger than 120 J / cm ² , the decomposition reaction of the charge transporting material becomes remarkable, and the electrical characteristics are deteriorated.

Next, the surface layer coating method of the present invention will be described. Examples of the method for coating the surface layer of the photoreceptor generally include a spray coating method, a ring coating method, and a dip coating method.
When the crosslinked surface layer is a surface portion of a photosensitive layer having a multilayer structure or a single layer structure, the thickness of the crosslinked surface layer is preferably 1 to 20 μm, and more preferably 2 to 10 μm. If the thickness is less than 1 μm, the durability varies due to uneven film thickness. If the thickness is more than 20 μm, the entire thickness of the charge transport layer is increased, and the reproducibility of the image is reduced due to the diffusion of charges. When the crosslinked surface layer is a charge transport layer of the photoreceptor, the thickness of the crosslinked surface layer is preferably 10 to 30 μm, and more preferably 10 to 25 μm. If the thickness is less than 10 μm, a sufficient charging potential cannot be maintained. If the thickness is more than 30 μm, peeling from the conductive substrate or the undercoat layer tends to occur due to volume shrinkage during curing.

  Next, the constituent material of the surface layer coating solution of the present invention will be described. In the present invention, a polymerizable compound that crosslinks by light energy is used as the surface layer coating liquid. In particular, (a) a tri- or higher functional radical polymerizable monomer having no charge transport structure and (b) charge transport. It is preferable to use a mixture in which a radically polymerizable compound having a crystalline structure is mixed. Examples of the trifunctional or higher functional radical polymerizable monomer having no charge transporting structure (a) include hole transporting structures such as triarylamine, hydrazone, pyrazoline, and carbazole, such as condensed polycyclic quinone, diphenoquinone, and cyano. A monomer having no electron transport structure such as an electron-withdrawing aromatic ring having a group or a nitro group and having three or more radically polymerizable functional groups. The radical polymerizable functional group may be any group 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.

As the 1-substituted ethylene functional group, for example, a functional group represented by the following general formula (1) is preferably exemplified.
CH ₂ = _{CH-X 1} - Formula (1)
However, the general formula (1), X ₁ is an optionally substituted phenylene group, an arylene group, an alkenylene group which may have a substituent such as a naphthylene group, -CO- group, —COO— group, —CON (R ₃₀ ) — group (wherein R ₃₀ is a hydrogen atom, an alkyl group such as a methyl group or an ethyl group, an aralkyl group such as a benzyl group, a naphthylmethyl group or a phenethyl group, a phenyl group, Represents an aryl group such as a naphthyl group), or an -S- group.
Specific examples of these substituents include vinyl, styryl, 2-methyl-1,3-butadienyl, vinylcarbonyl, acryloyloxy, acryloylamide, and vinylthioether groups.

As the 1,1-substituted ethylene functional group, for example, a functional group represented by the following general formula (2) is preferably exemplified.
_{CH 2 = C (Y) -X} 2 - Formula (2)
In the general formula (2), Y represents 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 naphthyl. An aryl group such as a group, an alkoxy group such as a halogen atom, a cyano group, a nitro group, a methoxy group or an ethoxy group, a —COOR ₃₁ group (where R ₃₁ is a hydrogen atom, an optionally substituted methyl group) , An alkyl group such as an ethyl group, an optionally substituted benzyl, an aralkyl group such as a phenethyl group, an optionally substituted phenyl group, an aryl group such as a naphthyl group), or —CONR ₃₂ R ₃₃ (wherein R ₃₂ and R ₃₃ are each a hydrogen atom, an optionally substituted methyl group, an alkyl group such as an ethyl group, an optionally substituted benzyl group, a naphthylmethyl group, Ah There is an aralkyl group such as a phenethyl group, or a substituent a phenyl group which may have a represents an aryl group such as a naphthyl group, may be the same or different from each other.) Further, X ₂ is the formula The same substituent as X _{1 in} (1), a single bond, and an alkylene group are represented. However, Y, at least one oxycarbonyl group in X _2, a cyano group, an alkenylene group, and an aromatic ring.
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, for example, a halogen atom, a nitro group, a cyano group, a methyl group, an alkyl group such as an ethyl group, a methoxy group, an ethoxy group, and the like And aryloxy groups such as phenoxy group, aryl groups such as phenyl group and naphthyl group, aralkyl groups such as benzyl group and phenethyl group, and the like.

  Among these radical polymerizable functional groups, an acryloyloxy group and a methacryloyloxy group are particularly useful, and a compound having three or more acryloyloxy groups includes, for example, a compound having three or more hydroxyl groups in the molecule. It can be obtained by an ester reaction or a transesterification reaction using acrylic acid (salt), acrylic acid halide, and acrylic ester. A compound having three or more methacryloyloxy groups can be obtained in the same manner. Further, the radical polymerizable functional groups in the monomer having three or more radical polymerizable functional groups may be the same or different.

Specific examples of the trifunctional or higher-functional radical polymerizable monomer (a) having no charge transporting structure include the following, but are not limited to these compounds.
That is, examples of the radical polymerizable monomer (A) used in the present invention include trimethylolpropane triacrylate (TMPTA), trimethylolpropane trimethacrylate, HPA-modified (alkylene-modified) trimethylolpropane triacrylate, EO-modified ( (Ethyleneoxy modified) trimethylolpropane triacrylate, PO modified (propyleneoxy modified) trimethylolpropane triacrylate, caprolactone modified trimethylolpropane triacrylate, HPA modified trimethylolpropane trimethacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate (PETTA) ), Glycerol triacrylate, ECH-modified (epichlorohydrin-modified) glycero Triacrylate, EO modified glycerol triacrylate, PO modified glycerol triacrylate, tris (acryloxyethyl) isocyanurate, dipentaerythritol hexaacrylate (DPHA), caprolactone modified dipentaerythritol hexaacrylate, dipentaerythritol hydroxypentaacrylate, alkyl modified Dipentaerythritol pentaacrylate, alkyl-modified dipentaerythritol tetraacrylate, alkyl-modified dipentaerythritol triacrylate, dimethylolpropane tetraacrylate (DTMPTA), pentaerythritol ethoxytetraacrylate, EO-modified phosphate triacrylate, 2, 2, 5, 5, -tetrahydroxymethylcyclopentanone tetra Such as acrylate and the like, which may be used in combination either alone or in combination. The reason for the modification is to lower the viscosity of the monomer and make it easier to handle.

  The trifunctional or higher functional radical polymerizable monomer having no charge transport structure used in the present invention is a ratio of molecular weight to the number of functional groups in the monomer in order to form a dense crosslink in the cross-linked surface layer. (Molecular weight / functional group number) is preferably 250 or less. Further, when this ratio is larger than 250, the crosslinked surface layer is soft and wear resistance is somewhat lowered. Therefore, among the monomers exemplified above, monomers having a modifying group such as HPA, EO, and PO are extremely long. It is not preferable to use one having a modifying group alone.

  Moreover, the component ratio of the trifunctional or higher functional radical polymerizable monomer having no charge transporting structure used for the crosslinked surface layer is 20 to 80% by weight, preferably 30 to 70% by weight, based on the total amount of the crosslinked surface layer. When the monomer component is less than 20% by weight, the three-dimensional cross-linking density of the cross-linked surface layer is small, and a drastic improvement in wear resistance is not achieved as compared with the case of using a conventional thermoplastic binder resin. On the other hand, if it exceeds 80% by weight, the content of the charge transporting compound is lowered, and the electrical characteristics are deteriorated. Since the required wear resistance and electrical characteristics differ depending on the process used, it cannot be said unconditionally, but considering the balance of both characteristics, the range of 30 to 70% by weight is most preferable.

The radically polymerizable compound having a (b) charge transporting structure used in the present invention is a hole transporting structure such as triarylamine, hydrazone, pyrazoline, carbazole, such as condensed polycyclic quinone, diphenoquinone, cyano group, etc. A compound having an electron transport structure such as an electron-withdrawing aromatic ring having a nitro group and having a radical polymerizable functional group. Examples of the radical polymerizable functional group include those previously shown for the radical polymerizable monomer, and acryloyloxy group and methacryloyloxy group are particularly useful. As the charge transporting structure, a triarylamine structure is highly effective.
Furthermore, when a compound represented by the structure of the following general formula (3) or (4) is used, electrical characteristics such as sensitivity and residual potential are favorably maintained.

〔式中、Ｒ_１は水素原子、ハロゲン原子、置換基を有してもよいアルキル基、置換基を有してもよいアラルキル基、置換基を有してもよいアリール基、シアノ基、ニトロ基、アルコキシ基、−ＣＯＯＲ_２（Ｒ_２は水素原子、置換基を有してもよいアルキル基、置換基を有してもよいアラルキル基又は置換基を有してもよいアリール基）、ハロゲン化カルボニル基若しくはＣＯＮＲ_３Ｒ_４（Ｒ_３及びＲ_４は水素原子、ハロゲン原子、置換基を有してもよいアルキル基、置換基を有してもよいアラルキル基又は置換基を有してもよいアリール基を示し、互いに同一であっても異なっていてもよい）を表わし、Ａｒ_１、Ａｒ_２は置換もしくは未置換のアリーレン基を表わし、同一であっても異なってもよい。Ａｒ_３、Ａｒ_４は置換もしくは未置換のアリール基を表わし、同一であっても異なってもよい。Ｘは単結合、置換もしくは無置換のアルキレン基、置換もしくは無置換のシクロアルキレン基、置換もしくは無置換のアルキレンエーテル基、酸素原子、硫黄原子、ビニレン基を表わし、Ｚは置換もしくは無置換のアルキレン基、置換もしくは無置換のアルキレンエーテル基、アルキレンオキシカルボニル基を表わし、ｍとｎは０〜３の整数を表わす。〕

[Wherein, R ₁ represents a hydrogen atom, a halogen atom, an alkyl group which may have a substituent, an aralkyl group which may have a substituent, an aryl group which may have a substituent, a cyano group, a nitro group, Group, alkoxy group, —COOR ₂ (R ₂ is a hydrogen atom, an alkyl group which may have a substituent, an aralkyl group which may have a substituent or an aryl group which may have a substituent), halogen Carbonyl group or CONR ₃ R ₄ (R ₃ and R ₄ may have a hydrogen atom, a halogen atom, an alkyl group which may have a substituent, an aralkyl group which may have a substituent, or a substituent. Represents a good aryl group, which may be the same or different from each other, and Ar ₁ and Ar ₂ represent a substituted or unsubstituted arylene group, which may be the same or different. Ar ₃ and Ar ₄ represent a substituted or unsubstituted aryl group, and may be the same or different. X represents a single bond, a substituted or unsubstituted alkylene group, a substituted or unsubstituted cycloalkylene group, a substituted or unsubstituted alkylene ether group, an oxygen atom, a sulfur atom, or a vinylene group, and Z represents a substituted or unsubstituted alkylene. Represents a group, a substituted or unsubstituted alkylene ether group or an alkyleneoxycarbonyl group, and m and n each represents an integer of 0 to 3; ]

In the general formulas (3) and (4), examples of the alkyl group in R ₁ include a methyl group, an ethyl group, a propyl group, and a butyl group. Examples of the aryl group include a phenyl group and a naphthyl group. As benzyl group, phenethyl group, naphthylmethyl group, and alkoxy groups include methoxy group, ethoxy group, propoxy group, etc., which are halogen atom, nitro group, cyano group, methyl group, ethyl group, respectively. Or an alkyl group such as methoxy group or ethoxy group, an aryloxy group such as phenoxy group, an aryl group such as phenyl group or naphthyl group, an aralkyl group such as benzyl group or phenethyl group, etc. .
Particularly preferred among R ₁ are a hydrogen atom and a methyl group.

Ar ₃ and Ar ₄ represent a substituted or unsubstituted aryl group. In the present invention, the aryl group includes a condensed polycyclic hydrocarbon group, a non-condensed cyclic hydrocarbon group, and a heterocyclic group, and includes the following groups.

  The condensed polycyclic hydrocarbon group preferably has 18 or less carbon atoms forming a ring, for example, a pentanyl group, an indenyl group, a naphthyl group, an azulenyl group, a heptaenyl group, a biphenylenyl group, an As-indacenyl group. , S-indacenyl group, fluorenyl group, acenaphthylenyl group, preadenyl group, acenaphthenyl group, phenalenyl group, phenanthryl group, anthryl group, fluoranthenyl group, acephenanthrenyl group, aceanthrylenyl group, triphenylyl group, pyrenyl group , A chrycenyl group, a naphthacenyl group, and the like.

  Examples of the non-fused cyclic hydrocarbon group include monovalent groups of monocyclic hydrocarbon compounds such as benzene, diphenyl ether, polyethylene diphenyl ether, diphenyl thioether and diphenyl sulfone, or biphenyl, polyphenyl, diphenylalkane, diphenylalkene, diphenylalkyne, Monovalent groups of non-condensed polycyclic hydrocarbon compounds such as triphenylmethane, distyrylbenzene, 1,1-diphenylcycloalkane, polyphenylalkane, and polyphenylalkene, or ring assemblies such as 9,9-diphenylfluorene And monovalent groups of hydrocarbon compounds.

  Examples of the heterocyclic group include monovalent groups such as carbazole, dibenzofuran, dibenzothiophene, oxadiazole, and thiadiazole.

The aryl group represented by Ar ₃ or Ar ₄ may have a substituent as shown below, for example.
(1) Halogen atom, cyano group, nitro group and the like.
(2) Alkyl groups, preferably C ₁ -C _12, especially C ₁ -C ₈ , more preferably C ₁ -C ₄ linear or branched alkyl groups, further including fluorine atoms , a hydroxyl group, a cyano _group, an alkoxy group of C 1 -C _4, a phenyl group or a halogen _atom, which may have a phenyl group substituted by an alkoxy group C 1 -C ₄ alkyl or _C 1 -C ₄ Good. Specifically, methyl group, ethyl group, n-butyl group, i-propyl group, t-butyl group, s-butyl group, n-propyl group, trifluoromethyl group, 2-hydroxyethyl group, 2-ethoxyethyl Group, 2-cyanoethyl group, 2-methoxyethyl group, benzyl group, 4-chlorobenzyl group, 4-methylbenzyl group, 4-phenylbenzyl group and the like.
(3) An alkoxy group (—ORa), and Ra represents an alkyl group defined in (2). Specifically, methoxy group, ethoxy group, n-propoxy group, i-propoxy group, t-butoxy group, n-butoxy group, s-butoxy group, i-butoxy group, 2-hydroxyethoxy group, benzyloxy group And a trifluoromethoxy group.
(4) An aryloxy group, and examples of the aryl group include a phenyl group and a naphthyl group. It _may contain an alkoxy group having C 1 -C _4, alkyl group, or a halogen atom C 1 -C ₄ as a substituent. Specific examples include a phenoxy group, a 1-naphthyloxy group, a 2-naphthyloxy group, a 4-methoxyphenoxy group, and a 4-methylphenoxy group.
(5) Alkyl mercapto group or aryl mercapto group, and specific examples include methylthio group, ethylthio group, phenylthio group, p-methylphenylthio group and the like.
(6)

（式中、Ｒ_１０及びＲ_１１は各々独立に水素原子、前記（２）で定義したアルキル基、またはアリール基を表わす。アリール基としては、例えばフェニル基、ビフェニル基又はナフチル基が挙げられ、これらはＣ_１〜Ｃ_４のアルコキシ基、Ｃ_１〜Ｃ_４のアルキル基またはハロゲン原子を置換基として含有してもよい。Ｒ_１０及びＲ_１１は共同で環を形成してもよい。）
具体的には、アミノ基、ジエチルアミノ基、Ｎ−メチル−Ｎ−フェニルアミノ基、Ｎ，Ｎ−ジフェニルアミノ基、Ｎ，Ｎ−ジ（トリール）アミノ基、ジベンジルアミノ基、ピペリジノ基、モルホリノ基、ピロリジノ基等が挙げられる。
（７）メチレンジオキシ基、又はメチレンジチオ基等のアルキレンジオキシ基又はアルキレンジチオ基等が挙げられる。
（８）置換又は無置換のスチリル基、置換又は無置換のβ−フェニルスチリル基、ジフェニルアミノフェニル基、ジトリルアミノフェニル基等。
前記Ａｒ_１、Ａｒ_２で表わされるアリーレン基としては、前記Ａｒ_３、Ａｒ_４で表わされるアリール基から誘導される２価基である。
前記Ｘは単結合、置換もしくは無置換のアルキレン基、置換もしくは無置換のシクロアルキレン基、置換もしくは無置換のアルキレンエーテル基、酸素原子、硫黄原子、ビニレン基を表わす。
前記Ｘにおけるアルキレン基としては、Ｃ_１〜Ｃ_１２、好ましくはＣ_１〜Ｃ_８、更に好ましくはＣ_１〜Ｃ_４の直鎖または分岐鎖のアルキレン基であり、これらのアルキレン基には更にフッ素原子、水酸基、シアノ基、Ｃ_１〜Ｃ_４のアルコキシ基、フェニル基又はハロゲン原子、Ｃ_１〜Ｃ_４のアルキル基もしくはＣ_１〜Ｃ_４のアルコキシ基で置換されたフェニル基を有していてもよい。具体的にはメチレン基、エチレン基、ｎ−ブチレン基、ｉ−プロピレン基、ｔ−ブチレン基、ｓ−ブチレン基、ｎ−プロピレン基、トリフルオロメチレン基、２−ヒドロキシエチレン基、２−エトキシエチレン基、２−シアノエチレン基、２−メトキシエチレン基、ベンジリデン基、フェニルエチレン基、４−クロロフェニルエチレン基、４−メチルフェニルエチレン基、４−ビフェニルエチレン基等が挙げられる。
前記Ｘにおけるシクロアルキレン基としては、Ｃ_５〜Ｃ_７の環状アルキレン基であり、これらの環状アルキレン基にはフッ素原子、水酸基、Ｃ_１〜Ｃ_４のアルキル基、Ｃ_１〜Ｃ_４のアルコキシ基などの置換基を有していても良い。具体的なシクロアルキレン基としてはシクロヘキシリデン基、シクロへキシレン基、３，３−ジメチルシクロヘキシリデン基等が挙げられる。
前記Ｘにおけるアルキレンエーテル基としては、エチレンオキシ、プロピレンオキシ、エチレングリコール、プロピレングリコール、ジエチレングリコール、テトラエチレングリコール、トリプロピレングリコールを表わし、アルキレンエーテル基のアルキレン基はヒドロキシル基、メチル基、エチル基等の置換基を有してもよい。
前記Ｘにおけるビニレン基は、

(Wherein R ₁₀ and R ₁₁ each independently represent a hydrogen atom, an alkyl group defined in (2) above, or an aryl group. Examples of the aryl group include a phenyl group, a biphenyl group, and a naphthyl group. these _C 1 -C ₄ alkoxy _groups, C 1 -C good _{.R 10} and _{R 11} may contain, as a substituent, an alkyl group or a halogen atom ₄ may be linked to form a ring.)
Specifically, amino group, diethylamino group, N-methyl-N-phenylamino group, N, N-diphenylamino group, N, N-di (tolyl) amino group, dibenzylamino group, piperidino group, morpholino group And pyrrolidino group.
(7) An alkylenedioxy group or an alkylenedithio group such as a methylenedioxy group or a methylenedithio group.
(8) A substituted or unsubstituted styryl group, a substituted or unsubstituted β-phenylstyryl group, a diphenylaminophenyl group, a ditolylaminophenyl group, and the like.
The arylene group represented by Ar ₁ and Ar ₂ is a divalent group derived from the aryl group represented by Ar ₃ and Ar ₄ .
X represents a single bond, a substituted or unsubstituted alkylene group, a substituted or unsubstituted cycloalkylene group, a substituted or unsubstituted alkylene ether group, an oxygen atom, a sulfur atom, or a vinylene group.
The alkylene group in X is a C _{1 to} C ₁₂ , preferably C _{1 to} C ₈ , more preferably C _{1 to} C ₄ linear or branched alkylene group, and these alkylene groups further include fluorine. atom, a hydroxyl group, a cyano _group, optionally having a C 1 -C ₄ alkoxy group, a phenyl group or a halogen _atom, C 1 -C phenyl group substituted by ₄ alkyl or alkoxy group of _C 1 -C ₄ Also good. Specifically, methylene group, ethylene group, n-butylene group, i-propylene group, t-butylene group, s-butylene group, n-propylene group, trifluoromethylene group, 2-hydroxyethylene group, 2-ethoxyethylene. Group, 2-cyanoethylene group, 2-methoxyethylene group, benzylidene group, phenylethylene group, 4-chlorophenylethylene group, 4-methylphenylethylene group, 4-biphenylethylene group and the like.
The cycloalkylene group in X is a C _{5 to} C ₇ cyclic alkylene group, and these cyclic alkylene groups include a fluorine atom, a hydroxyl group, a C _{1 to} C ₄ alkyl group, and a C _{1 to} C ₄ alkoxy group. And may have a substituent such as Specific examples of the cycloalkylene group include a cyclohexylidene group, a cyclohexylene group, and a 3,3-dimethylcyclohexylidene group.
The alkylene ether group in X represents ethyleneoxy, propyleneoxy, ethylene glycol, propylene glycol, diethylene glycol, tetraethylene glycol, tripropylene glycol, and the alkylene group of the alkylene ether group includes a hydroxyl group, a methyl group, an ethyl group, and the like. You may have a substituent.
The vinylene group in X is

で表わされ、Ｒ_１２は水素、アルキル基〔前記（２）で定義されるアルキル基と同じ〕、アリール基（前記Ａｒ_３、Ａｒ_４で表わされるアリール基と同じ）、ａは１または２、ｂは１〜３を表わす。
前記Ｚは置換もしくは未置換のアルキレン基、置換もしくは無置換のアルキレンエーテル基、アルキレンオキシカルボニル基を表わす。置換もしくは未置換のアルキレン基としては、前記Ｘのアルキレン基と同様なものが挙げられる。置換もしくは無置換のアルキレンエーテル基としては、前記Ｘのアルキレンエーテル基が挙げられる。アルキレンオキシカルボニル基としては、カプロラクトン変性基が挙げられる。

R ₁₂ is hydrogen, an alkyl group (same as the alkyl group defined in (2) above), an aryl group (same as the aryl group represented by Ar ₃ or Ar ₄ above), a is 1 or 2 , B represents 1-3.
Z represents a substituted or unsubstituted alkylene group, a substituted or unsubstituted alkylene ether group, or an alkyleneoxycarbonyl group. Examples of the substituted or unsubstituted alkylene group include the same alkylene groups as those described above for X. Examples of the substituted or unsubstituted alkylene ether group include the alkylene ether group represented by X. Examples of the alkyleneoxycarbonyl group include a caprolactone-modified group.

  Further, the radically polymerizable compound having a charge transport structure of the present invention is more preferably a compound having the structure of the following general formula (5).

（式中、ｐ、ｑ、ｏはそれぞれ０又は１の整数、Ｒ_５は水素原子、メチル基を表わし、Ｒ_６、Ｒ_７は水素原子以外の置換基で炭素数１〜６のアルキル基を表わし、複数の場合は異なっても良い。ｓ、ｔは０〜３の整数を表わす。Ｚ_２は単結合、メチレン基、エチレン基、

(In the formula, p, q and o are each an integer of 0 or 1, R ₅ represents a hydrogen atom or a methyl group, and R ₆ and R ₇ represent a substituent other than a hydrogen atom and an alkyl group having 1 to 6 carbon atoms. And a plurality of s and t each represent an integer of 0 to _3. Z ₂ represents a single bond, a methylene group, an ethylene group,

を表わす。）
上記一般式で表わされる化合物としては、Ｒ_６、Ｒ_７の置換基として、特にメチル基、エチル基である化合物が好ましい。

Represents. )
As the compound represented by the above general formula, a compound having a methyl group or an ethyl group is particularly preferable as a substituent for R ₆ and R ₇ .

  The radically polymerizable compound having the charge transport structure represented by the general formulas (3) and (4), particularly (5) used in the present invention is polymerized by opening a double bond between carbon and carbon on both sides. In a polymer incorporated in a chain polymer and crosslinked by polymerization with a tri- or higher functional radical polymerizable monomer, the polymer exists in the main chain of the polymer, and the main chain-main chain Present in the cross-linked chain (in this cross-linked chain, the inter-molecular cross-linked chain between one polymer and the other polymer, the site with the main chain folded in one polymer and the main chain In other words, there is an intramolecular cross-linked chain that is cross-linked with other sites derived from the polymerized monomer at a position away from this), but even if it is present in the main chain or in the cross-linked chain Even so, the triarylamine structure suspended from the chain moiety is radial from the nitrogen atom. It has at least three aryl groups arranged in the direction and is bulky, but is not directly bonded to the chain part, but is suspended from the chain part via a carbonyl group etc. Since these triarylamine structures can be arranged adjacent to each other in the polymer, the structural distortion in the molecule is small, and the surface layer of the electrophotographic photosensitive member In this case, it is presumed that an intramolecular structure that is relatively free from interruption of the charge transport pathway can be taken.

  In the present invention, the specific acrylate compound represented by the following general formula (6) can also be used favorably as a radical polymerizable compound having a charge transporting structure.

Ａｒ_５は置換又は無置換の芳香族炭化水素骨格からなる一価基または二価基を表わす。芳香族炭化水素としては、ベンゼン、ナフタレン、フェナントレン、ビフェニル、１，２，３，４−テトラヒドロナフタレン等が挙げられる。
置換基としては、炭素数１〜１２のアルキル基、炭素数１〜１２のアルコキシ基、ベンジル基、ハロゲン原子が挙げられる。また、上記アルキル基、アルコキシ基は、さらにハロゲン原子、フェニル基を置換基として有していても良い。
Ａｒ_６は、少なくとも１個の３級アミノ基を有する芳香族炭化水素骨格からなる一価基または二価基、もしくは少なくとも１個の３級アミノ基を有する複素環式化合物骨格からなる一価基または二価基を表わすが、ここで、３級アミノ基を有する芳香族炭化水素骨格とは下記一般式（７）で表わされる。

Ar ₅ represents a monovalent group or a divalent group composed of a substituted or unsubstituted aromatic hydrocarbon skeleton. Examples of the aromatic hydrocarbon include benzene, naphthalene, phenanthrene, biphenyl, 1,2,3,4-tetrahydronaphthalene and the like.
Examples of the substituent include an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, a benzyl group, and a halogen atom. The alkyl group and alkoxy group may further have a halogen atom or a phenyl group as a substituent.
Ar ₆ is a monovalent group or divalent group composed of an aromatic hydrocarbon skeleton having at least one tertiary amino group, or a monovalent group composed of a heterocyclic compound skeleton having at least one tertiary amino group. Alternatively, it represents a divalent group. Here, the aromatic hydrocarbon skeleton having a tertiary amino group is represented by the following general formula (7).

（式中、Ｒ_１３、Ｒ_１４はアシル基、置換もしくは無置換のアルキル基、置換もしくは無置換のアリール基を表わす。Ａｒ_７はアリール基を表わす。ｗは１〜３の整数を表わす。）
Ｒ_１３、Ｒ_１４のアシル基としてはアセチル基、プロピオニル基、ベンゾイル基等が挙げられる。
Ｒ_１３、Ｒ_１４の置換もしくは無置換のアルキル基はＡｒ_５の置換基で述べたアルキル基と同様である。
Ｒ_１３、Ｒ_１４の置換もしくは無置換のアリール基は、フェニル基、ナフチル基、ビフェニリル基、ターフェニリル基、ピレニル基、フルオレニル基、９，９−ジメチル−２−フルオレニル基、アズレニル基、アントリル基、トリフェニレニル基、クリセニル基に加えて下記一般式（８）で表わされる基を挙げることができる。

(Wherein R ₁₃ and R ₁₄ represent an acyl group, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group. Ar ₇ represents an aryl group. W represents an integer of 1 to 3)
Examples of the acyl group for R ₁₃ and R ₁₄ include an acetyl group, a propionyl group, and a benzoyl group.
The substituted or unsubstituted alkyl group for R ₁₃ and R ₁₄ is the same as the alkyl group described for the substituent for Ar ₅ .
The substituted or unsubstituted aryl group of R ₁₃ and R ₁₄ is a phenyl group, a naphthyl group, a biphenylyl group, a terphenylyl group, a pyrenyl group, a fluorenyl group, a 9,9-dimethyl-2-fluorenyl group, an azulenyl group, an anthryl group, In addition to the triphenylenyl group and the chrysenyl group, a group represented by the following general formula (8) can be exemplified.

［式中、Ｂは−Ｏ−、−Ｓ−、−ＳＯ−、−ＳＯ_２−、−ＣＯ−及び以下の二価基から選ばれる。

[Wherein, B is selected from —O—, —S—, —SO—, —SO ₂ —, —CO— and the following divalent groups.

（ここで、Ｒ_２１は、水素原子、Ａｒ_５で定義された置換もしくは無置換のアルキル基、アルコキシ基、ハロゲン原子、Ｒ_１３で定義された置換もしくは無置換のアリール基、アミノ基、ニトロ基、シアノ基を表し、Ｒ_２２は、水素原子、Ａｒ_５定義された置換もしくは無置換のアルキル基、Ｒ_１３で定義された置換もしくは無置換のアリール基を表し、ｉは１〜１２の整数、ｊは１〜３の整数を表わす。）］
Ｒ_２１のアルコキシ基の具体例としてはメトキシ基、エトキシ基、ｎ−プロポキシ基、ｉ−プロポキシ基、ｎ−ブトキシ基、ｉ−ブトキシ基、ｓ−ブトキシ基、ｔ−ブトキシ基、２−ヒドロキシエトキシ基、２−シアノエトキシ基、ベンジルオキシ基、４−メチルベンジルオキシ基、トリフルオロメトキシ基等が挙げられる。
Ｒ_２１のハロゲン原子としてはフッ素原子、塩素原子、臭素原子、ヨウ素原子が挙げられる。
Ｒ_２１のアミノ基としては、ジフェニルアミノ基、ジトリルアミノ基、ジベンジルアミノ基、４−メチルベンジル基等が挙げられる。
Ａｒ_７のアリール基としてはフェニル基、ナフチル基、ビフェニリル基、ターフェニリル基、ピレニル基、フルオレニル基、９，９−ジメチル−２−フルオレニル基、アズレニル基、アントリル基、トリフェニレニル基、クリセニル基を挙げることができる。
Ａｒ_７、Ｒ_１３、Ｒ_１４は、Ａｒ_５で定義されたアルキル基、アルコキシ基、ハロゲン原子を置換基として有していても良い。
また、３級アミノ基を有する複素環式化合物骨格としては、ピロール、ピラゾール、イミダゾール、トリアゾール、ジオキサゾール、インドール、イソインドール、ベンズイミダゾール、ベンゾトリアゾール、ベンゾイソキサジン、カルバゾール、フェノキサジン等のアミン構造を有する複素環化合物が挙げられる。これらは、Ａｒ_５で定義されたアルキル基、アルコキシ基、ハロゲン原子を置換基として有していても良い。
Ｂ_１、Ｂ_２はアクリロイルオキシ基、メタクリロイルオキシ基、ビニル基、アクリロイルオキシ基又はメタクリロイルオキシ基又はビニル基を有するアルキル基、アクリロイルオキシ基又はメタクリロイルオキシ基又はビニル基を有するアルコキシ基を表わす。アルキル基、アルコキシ基は、Ａｒ_５で述べたものが同様に適用される。これらＢ_１、Ｂ_２はどちらか一方のみが存在し、両方の存在は除外される。
一般式（６）のアクリル酸エステル化合物においてより好ましい構造として下記一般式（９）の化合物を挙げることができる。

(Wherein R ₂₁ is a hydrogen atom, a substituted or unsubstituted alkyl group defined by Ar ₅ , an alkoxy group, a halogen atom, a substituted or unsubstituted aryl group defined by R ₁₃ , an amino group, a nitro group; Represents a cyano group, R ₂₂ represents a hydrogen atom, a substituted or unsubstituted alkyl group defined by Ar ₅ , a substituted or unsubstituted aryl group defined by R ₁₃ , i is an integer of 1 to 12, j represents an integer of 1 to 3)]
Specific examples of the alkoxy group of R ₂₁ include methoxy group, ethoxy group, n-propoxy group, i-propoxy group, n-butoxy group, i-butoxy group, s-butoxy group, t-butoxy group, 2-hydroxyethoxy. Group, 2-cyanoethoxy group, benzyloxy group, 4-methylbenzyloxy group, trifluoromethoxy group and the like.
Examples of the halogen atom for R ₂₁ include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.
Examples of the amino group of R ₂₁ include a diphenylamino group, a ditolylamino group, a dibenzylamino group, and a 4-methylbenzyl group.
Examples of the aryl group of Ar ₇ include a phenyl group, a naphthyl group, a biphenylyl group, a terphenylyl group, a pyrenyl group, a fluorenyl group, a 9,9-dimethyl-2-fluorenyl group, an azulenyl group, an anthryl group, a triphenylenyl group, and a chrysenyl group. Can do.
Ar ₇ , R ₁₃ and R ₁₄ may have an alkyl group, an alkoxy group or a halogen atom defined by Ar ₅ as a substituent.
Examples of the heterocyclic compound skeleton having a tertiary amino group include amines such as pyrrole, pyrazole, imidazole, triazole, dioxazole, indole, isoindole, benzimidazole, benzotriazole, benzisoxazine, carbazole, and phenoxazine. Examples include heterocyclic compounds having a structure. These may have an alkyl group, an alkoxy group, or a halogen atom defined by Ar ₅ as a substituent.
B ₁ and B ₂ represent an acryloyloxy group, a methacryloyloxy group, a vinyl group, an acryloyloxy group, a methacryloyloxy group, an alkyl group having a vinyl group, an acryloyloxy group, a methacryloyloxy group, or an alkoxy group having a vinyl group. As the alkyl group and alkoxy group, those described for Ar ₅ are similarly applied. Only _{one of} these B ₁ and B ₂ is present, and the presence of both is excluded.
As a more preferable structure in the acrylic ester compound of the general formula (6), a compound of the following general formula (9) can be exemplified.

式中、Ｒ_８、Ｒ_９は、置換もしくは無置換のアルキル基、置換もしくは無置換のアルコキシ基、ハロゲン原子を表わし、Ａｒ_７、Ａｒ_８は、置換もしくは無置換のアリール基またはアリレン基、置換又は無置換のベンジル基を表わす。アルキル基、アルコキシ基、ハロゲン原子は前記Ａｒ_５で述べたものが同様に適用される。
アリール基は、Ｒ_１３、Ｒ_１４で定義されたアリール基と同様である。アリレン基は、そのアリール基から誘導される二価基である。
Ｂ_１〜Ｂ_４は、一般式（６）におけるＢ_１、Ｂ_２と同様である。ｕは０〜５の整数、ｖは０〜４の整数を表わす。

In the formula, R ₈ and R ₉ represent a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group or a halogen atom, and Ar ₇ and Ar ₈ represent a substituted or unsubstituted aryl group or an arylene group, substituted Or an unsubstituted benzyl group is represented. As the alkyl group, alkoxy group, and halogen atom, those described for Ar ₅ are similarly applied.
The aryl group is the same as the aryl group defined by R ₁₃ and R ₁₄ . An arylene group is a divalent group derived from the aryl group.
B _{1 to} B ₄ are the same as B ₁ and B ₂ in the general formula (6). u represents an integer of 0 to 5, and v represents an integer of 0 to 4.

  The specific acrylic ester compound has the following characteristics. It is a tertiary amine compound having a stilbene-type conjugated structure, and has a developed conjugated system. By using a charge transporting compound with such a conjugated system, the charge injection property at the interface part of the cross-linked layer becomes very good, and intermolecular interaction is inhibited even when immobilized between cross-linked bonds. It is difficult and has good characteristics with respect to charge mobility. Further, it has an acryloyloxy group or a methacryloyloxy group having high radical polymerizability in the molecule, so that it rapidly gels during radical polymerization and does not cause excessive crosslinking distortion. The double bond of the stilbene structure in the molecule partially participates in the polymerization, and the polymerization is lower than the acryloyloxy group or methacryloyloxy group, so that a time difference occurs in the crosslinking reaction, thereby maximizing the distortion. In addition, since the number of cross-linking reactions per molecular weight can be increased due to the use of double bonds in the molecule, the cross-linking density can be increased and further improvement in wear resistance can be realized. . In addition, the degree of polymerization of this double bond can be adjusted depending on the crosslinking conditions, and an optimum crosslinked film can be easily produced. Such cross-linking participation in radical polymerization is a specific feature of the acrylate compound and does not occur in the α-phenylstilbene type structure as described above.

From the above, the use of the charge transporting compound having a radical polymerizable functional group represented by the general formula (6), particularly the general formula (9), while maintaining good electrical characteristics and generating cracks and the like. A film having a very high crosslinking density can be formed without causing any problems, thereby satisfying various characteristics of the photoconductor, preventing silica fine particles from being stuck in the photoconductor, and reducing image defects such as white spots. be able to.
Regarding the number of radical polymerizable functional groups, those having a small number of functional groups are preferable for the uniformity of the crosslinked structure, and those having a large number of functional groups are preferred for the wear resistance. In the present invention, it is possible to select and use it well from the balance of both.

  Specific examples of the radical polymerizable compound having a charge transporting structure used in the present invention, NO. 1-NO. 185 is shown in Table 1-1 to Table 1-12, but is not limited to compounds having these structures.

  Further, the radical polymerizable compound (b) having a charge transporting structure used in the present invention is important for imparting the charge transporting performance of the crosslinked surface layer, and this component is 20 to 80% by weight based on the total amount of the crosslinked surface layer. %, Preferably 30 to 70% by weight. When this component is less than 20% by weight, the charge transport performance of the crosslinked surface layer cannot be maintained sufficiently, and deterioration of electrical characteristics such as a decrease in sensitivity and an increase in residual potential appears with repeated use. On the other hand, if it exceeds 80% by weight, the content of the trifunctional or higher-functional radical polymerizable monomer having no charge transport structure is lowered, and the crosslink density is lowered, so that high wear resistance is not exhibited. Although the electrical characteristics and abrasion resistance required differ depending on the process used, it cannot be said unconditionally, but considering the balance of both characteristics, the range of 30 to 70% by weight is most preferable.

  The cross-linked surface layer of the present invention is a tri- or higher functional radical polymerizable compound in which the surface layer of the photosensitive layer has at least (i) a charge transporting structure in an electrophotographic photosensitive member having at least a photosensitive layer on a conductive support. It is formed by curing the monomer and (b) a radically polymerizable compound having a charge transporting structure. In addition to this, viscosity adjustment during coating, stress relaxation of the crosslinked surface layer, lower surface energy and friction Monofunctional and bifunctional radically polymerizable monomers, functional monomers and radically polymerizable oligomers can be used in combination for the purpose of imparting a function such as a reduction in coefficient. 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 cross-linked 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 50 parts by weight or less, preferably 30 parts by weight or less, with respect to 100 parts by weight of the tri- or higher functional radical polymerizable monomer.

  The surface layer of the present invention is an electrophotographic photosensitive member having at least a photosensitive layer on a conductive support, and the surface of the photosensitive layer has at least a trifunctional or higher functional radical polymerizable monomer having no charge transporting structure and a charge. It is formed by applying a solvent solution composition (coating solution) of a monomer mixture containing a monofunctional radically polymerizable compound having a transporting structure, drying, polymerizing and curing the composition. If necessary, a photopolymerization initiator may be used in the solvent solution composition in order to allow the crosslinking reaction to proceed efficiently.

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.
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.

  Furthermore, the coating liquid of the present invention can contain additives such as various plasticizers (for the purpose of stress relaxation and adhesion improvement), leveling agents, and low molecular charge transport materials having no radical reactivity as required. 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. 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.

  The crosslinked surface layer of the present invention applies a coating liquid containing a tri- or higher functional radical polymerizable monomer having no charge transport structure and a radical polymerizable compound having a charge transport structure to give light energy. Cured and formed. In some cases, the coating solution is applied after dilution. Examples of the solvent used include alcohols such as methanol, ethanol, propanol and butanol, ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone, ethyl acetate and acetic acid. Esters such as butyl, ethers such as tetrahydrofuran, dioxane, propyl ether, halogens such as dichloromethane, dichloroethane, trichloroethane, chlorobenzene, aromatics such as benzene, toluene, xylene, methyl cellosolve, ethyl cellosolve, cellosolve acetate, etc. Examples include cellosolve. 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 and the target film thickness, and is arbitrary, but the dilution ratio is preferably 5% to 40% from the viewpoint of film thickness controllability and surface leveling.

  Since the film thickness of the surface layer of the present invention varies depending on the layer structure of the photoreceptor in which the surface layer is used, it is described in accordance with the following description of 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.
FIG. 3 is a cross-sectional view showing the electrophotographic photosensitive member of the present invention, in which a single layer structure in which a photosensitive layer (33) having both a charge generating function and a charge transporting function is provided on a conductive support (31). This is a photoreceptor. FIG. 3A shows the case where the crosslinked surface layer is the entire photosensitive layer, and FIG. 3-B shows the case where the crosslinked surface layer is the surface portion of the photosensitive layer.

  FIG. 4 shows a photoreceptor having a laminated structure in which a charge generation layer (35) having a charge generation function and a charge transport layer (37) having a charge transport function are laminated on a conductive support (31). . FIG. 4-A shows the case where the cross-linked surface layer is the entire charge transport layer, and FIG. 4-B shows the case where the cross-linked surface layer is the surface portion of the charge transport layer.

<About conductive support>
As the conductive support (31), a material having a volume resistance of 10 ¹⁰ Ω · cm or less, for example, a metal such as aluminum, nickel, chromium, nichrome, copper, gold, silver, platinum, tin oxide, oxidation Metal oxide such as indium is deposited or sputtered to form film or cylindrical plastic, paper coated, or aluminum, aluminum alloy, nickel, stainless steel, etc. After conversion, a tube that has been subjected to surface treatment such as cutting, superfinishing, or polishing can be used. Further, an endless nickel belt and an endless stainless steel belt disclosed in Japanese Patent Application Laid-Open No. 52-36016 can be used as the conductive support (31).
In addition, the conductive support dispersed in a suitable binder resin and coated on the support can also be used as the conductive support (31) 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, Teflon (registered trademark) on a suitable cylindrical substrate. Those provided with a conductive layer can also be used favorably as the conductive support (31) 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 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 comprising a charge generation layer and a charge transport layer>
(Charge generation layer)
The charge generation layer (35) 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 a carbazole skeleton, azo pigments having a triphenylamine skeleton, azo pigments having a diphenylamine skeleton, dibenzothiophene skeleton Azo pigments having fluorenone skeleton, azo pigments having oxadiazole skeleton, azo pigments having bis-stilbene skeleton, azo pigments having distyryl oxadiazole skeleton, azo pigments having 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.

  The binder resin used as necessary for the charge generation layer (35) is polyamide, polyurethane, epoxy resin, polyketone, polycarbonate, silicone resin, acrylic resin, polyvinyl butyral, polyvinyl formal, polyvinyl ketone, polystyrene, poly-N-. Examples thereof include vinyl carbazole and 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. JP-A 09-104746, JP-A 09-110974, JP-A 09-110976, JP-A 09-157378, JP-A 09-221544, JP-A 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 (35) may contain a low molecular charge transport material.

Low molecular charge transport materials that can be used in combination with the charge generation layer (35) 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 (35) 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.

(About charge transport layer)
The charge transport layer (37) is a layer having a charge transport function, and the crosslinked surface layer having a charge transport structure of the present invention is useful as a charge transport layer. When the cross-linked surface layer is the entire charge transport layer (37), the radical polymerizable composition (charge transport structure of the present invention is formed on the charge generation layer (35) as described in the above cross-linked surface layer preparation method. A coating liquid containing a radically polymerizable monomer and a charge transporting compound having a radically polymerizable functional group, which are not included, is applied and cured by light energy to form a crosslinked surface layer. At this time, the film thickness of the crosslinked surface layer is 10 to 30 μm, preferably 10 to 25 μm. If it is thinner than 10 μm, a sufficient charging potential cannot be maintained, and if it is thicker than 30 μm, peeling from the lower layer tends to occur due to volume shrinkage during curing.

  When the cross-linked surface layer is formed on the surface portion of the charge transport layer (37) and the charge transport layer (37) has a laminated structure, the lower layer portion of the charge transport layer has a charge transport material having a charge transport function and a binder. The resin is dissolved or dispersed in a suitable solvent, and this is formed on the charge generation layer (35) by coating and drying, and a coating solution containing the radical polymerizable composition of the present invention is coated thereon. And cured by light energy.

As the charge transport material, the electron transport material, hole transport material and polymer charge transport material described in the charge generation layer (35) can be used. As described above, the use of the polymer charge transport material can reduce the solubility of the lower layer when the surface layer is applied, and is particularly useful.
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 lower layer portion of the charge transport layer, the same solvent as that for the charge generation layer can be used, but a solvent that dissolves the charge transport material and the binder resin well is suitable. These solvents may be used alone or in combination of two or more. The lower layer portion of the charge transport layer can be formed by a coating method similar to that for the charge generation layer (35).

If necessary, a plasticizer and a leveling agent can be added.
As a plasticizer that can be used in combination with the lower layer portion of the charge transport layer, those used as plasticizers for general resins such as dibutyl phthalate and dioctyl phthalate can be used as they are, and the amount used is 100 parts by weight of the binder resin. On the other hand, about 0 to 30 parts by weight is appropriate.
As a leveling agent that can be used in combination with the lower layer portion of the charge transport layer, silicone oils such as dimethyl silicone oil and methylphenyl silicone oil, and polymers or oligomers having a perfluoroalkyl group in the side chain are used. About 0 to 1 part by weight is appropriate for 100 parts by weight of the binder resin.
The thickness of the lower layer portion of the charge transport layer is appropriately about 5 to 40 μm, preferably about 10 to 30 μm.
When the cross-linked surface layer is the surface portion of the charge transport layer (37), the radical polymerizable composition of the present invention is contained on the lower layer portion of the charge transport layer as described in the method for preparing a cross-linked surface layer. After coating the coating liquid, it is cured by light energy to form a crosslinked surface layer. At this time, the film thickness of the crosslinked surface layer is 1 to 20 μm, preferably 2 to 10 μm. If the thickness is less than 1 μm, the durability varies due to uneven film thickness. If the thickness is more than 20 μm, the entire thickness of the charge transport layer is increased, and the reproducibility of the image is reduced due to the diffusion of charges.

<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, and the crosslinked surface layer having the charge transport structure of the present invention contains a charge generation material having a charge generation function, thereby providing a single layer structure. It is useful as a photosensitive layer. As described in the method for forming the charge generation layer, the charge generation material is dispersed together with the coating solution containing the radical polymerizable composition, applied onto the charge generation layer (35), and then cured by light energy. And a crosslinked surface layer is formed. In addition, you may add the liquid in which the charge generation material was previously disperse | distributed with the solvent to this coating material for bridge | crosslinking surface layers. At this time, the film thickness of the crosslinked surface layer is 10 to 30 μm, preferably 10 to 25 μm. If the thickness is less than 10 μm, a sufficient charging potential cannot be maintained. If the thickness is more than 30 μm, peeling from the conductive substrate or the undercoat layer tends to occur due to volume shrinkage during curing.

  Further, when the crosslinked surface layer is a surface portion of a photosensitive layer having a single layer structure, the lower layer portion of the photosensitive layer is composed of a charge generating material having a charge generating function, a charge transporting material having a charge transport function, and a binder resin in an appropriate solvent. It can be formed by dissolving or dispersing in, 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 (35) and the charge transport layer (37). As the binder resin, in addition to the binder resin previously mentioned in the section of the charge transport layer (37), the binder resin mentioned in the charge generation layer (35) may be mixed and used. In addition, the polymer charge transport materials listed above can also be used, which is useful in that contamination of the lower layer photosensitive layer composition into the crosslinked surface layer can be reduced. The thickness of the lower layer portion of the photosensitive layer is suitably about 5 to 30 μm, preferably about 10 to 25 μm.

When the crosslinked surface layer is a surface portion of a photosensitive layer having a single layer structure, the coating solution containing the radically polymerizable composition of the present invention and the charge generating material is applied onto the lower layer portion of the photosensitive layer as described above. Cured with light energy to form a crosslinked surface layer. At this time, the film thickness of the crosslinked surface layer is 1 to 20 μm, preferably 2 to 10 μm. When the thickness is less than 1 μm, the durability varies due to the film thickness unevenness.
The charge generation material contained in the photosensitive layer having a single layer structure is preferably 1 to 30% by weight based on the total amount of the photosensitive layer, and the binder resin contained in the lower layer portion of the photosensitive layer is 20 to 80% by weight of the total amount. The transport material is preferably used in an amount of 10 to 70 parts by weight.

<About the intermediate layer>
In the photoreceptor of the present invention, when the crosslinked surface layer is the surface portion of the photosensitive layer, it is possible to provide an intermediate layer for the purpose of suppressing mixing of lower layer components into the crosslinked surface layer or improving adhesion with the lower layer. is there. This intermediate layer prevents inhibition of the curing reaction and unevenness of the crosslinked surface layer caused by mixing of the lower photosensitive layer composition in the outermost surface layer containing the radical polymerizable composition. It is also possible to improve the adhesion between the lower photosensitive layer and the surface cross-linked 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. The thickness of the intermediate layer is suitably about 0.05 to 2 μm.

<About the undercoat layer>
In the photoreceptor of the present invention, an undercoat layer can be provided between the conductive support (31) 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 anodization, 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 suitably from 0 to 5 μm.

<Addition of antioxidant to each layer>
In the present invention, in order to improve environmental resistance, in order to prevent a decrease in sensitivity and an increase in residual potential, a surface cross-linked layer, a photosensitive layer, a charge generation layer, a charge transport layer, an undercoat layer, an intermediate layer An antioxidant can be added to each layer such as a layer.
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 ] Cryol ester, 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, ditetradecyl-3,3′-thiodipropionate, and the like.

(Organic phosphorus compounds)
Triphenylphosphine, tri (nonylphenyl) phosphine, tri (dinonylphenyl) phosphine, tricresylphosphine, tri (2,4-dibutylphenoxy) phosphine, and the like.
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.

<Image Forming Method and Apparatus>
Next, the image forming method and the image forming apparatus of the present invention will be described in detail with reference to the drawings.
The image forming method and the image forming apparatus of the present invention use a photoconductor having a smooth charge transporting surface cross-linked layer. For example, at least after the photoconductor is charged, exposed to an image, and developed, the image is held. An image forming method and an image forming apparatus including a process of transferring a toner image onto a body (transfer paper), fixing, and cleaning of the surface of a photoreceptor.
In some cases, an image forming method or the like in which an electrostatic latent image is directly transferred to a transfer member and developed does not necessarily have the above-described process arranged on a photosensitive member.
FIG. 5 is a schematic diagram illustrating an example of an image forming apparatus. A charging charger (3) is used as a means for charging the photoconductor on average. As the charging means, a corotron device, a scorotron device, a solid discharge element, a needle electrode device, a roller charging device, a conductive brush device, or the like is used, and a known system can be used.
In particular, the configuration of the present invention is effective when a charging unit such as a contact charging method or a non-contact proximity arrangement charging method is used in which the photosensitive composition is decomposed by proximity discharge from the charging unit. Here, the contact charging method is a charging method in which a charging roller, a charging brush, a charging blade, or the like is in direct contact with the photosensitive member. On the other hand, the proximity charging method is, for example, a type in which the charging roller is arranged in a non-contact state so as to have a gap of 200 μm or less between the surface of the photoreceptor and the charging means. If this gap is too large, the charging tends to become unstable, and if it is too small, the surface of the charging member may be contaminated when toner remaining on the photoreceptor exists. is there. Accordingly, the gap is suitably 10 to 200 μm, preferably 10 to 100 μm.

  Next, the image exposure unit (5) is used to form an electrostatic latent image on the uniformly charged photoreceptor (1). As the light source, all luminescent materials such as a fluorescent lamp, a tungsten lamp, a halogen lamp, a mercury lamp, a sodium lamp, a light emitting diode (LED), a semiconductor laser (LD), and an electroluminescence (EL) can be used. Various types of filters such as a sharp cut filter, a band pass filter, a near infrared cut filter, a dichroic filter, an interference filter, and a color temperature conversion filter can be used to irradiate only light in a desired wavelength range.

  Next, the developing unit (6) is used to visualize the electrostatic latent image formed on the photoreceptor (1). Development methods include a one-component development method using a dry toner, a two-component development method, and a wet development method using a wet toner. When the photosensitive member is positively (negatively) charged and image exposure is performed, a positive (negative) electrostatic latent image is formed on the surface of the photosensitive member. A positive image can be obtained by developing this with negative (positive) toner (electrodetection fine particles), and a negative image can be obtained by developing with positive (negative) toner.

  Next, a transfer charger (10) is used to transfer the toner image visualized on the photoconductor onto the transfer body (9). In addition, a pre-transfer charger (7) may be used for better transfer. As these transfer means, a transfer charger, an electrostatic transfer method using a bias roller, a mechanical transfer method such as an adhesive transfer method and a pressure transfer method, and a magnetic transfer method can be used. As the electrostatic transfer method, the charging means can be used.

  Next, a separation charger (11) and a separation claw (12) are used as means for separating the transfer body (9) from the photoreceptor (1). As other separation means, electrostatic adsorption induction separation, side end belt separation, tip grip conveyance, curvature separation, and the like are used. As the separation charger (11), the charging means can be used.

  Next, a fur brush (14) and a cleaning blade (15) are used to clean the toner remaining on the photoreceptor after transfer. Further, a pre-cleaning charger (13) may be used in order to perform cleaning more efficiently. Other cleaning means include a web method, a magnet brush method, and the like, but each may be used alone or in combination.

Next, a neutralizing unit is used for the purpose of removing the latent image on the photoreceptor as required. As the charge removal means, a charge removal lamp (2) and a charge removal charger are used, and the exposure light source and the charging means can be used respectively.
In addition, known processes can be used for reading, feeding, fixing, paper discharge and the like that are not close to the photoconductor.

The present invention is an image forming method and an image forming apparatus using the electrophotographic photoreceptor according to the present invention for such image forming means.
The image forming means may be fixedly incorporated in a copying apparatus, facsimile, or printer, but may be incorporated in these apparatuses in the form of a process cartridge and detachable. An example of the process cartridge is shown in FIG.
The process cartridge for the image forming apparatus includes a photoreceptor (101), and in addition, a charging unit (102), a developing unit (104), a transfer unit (106), a cleaning unit (107), and a discharging unit (not shown). ), And an apparatus (part) that can be attached to and detached from the image forming apparatus main body.

  Referring to the image forming process by the apparatus illustrated in FIG. 6, the surface of the photoconductor (101) is exposed by charging by the charging means (102) and exposure by the exposure means (103) while rotating in the direction of the arrow. An electrostatic latent image corresponding to the image is formed, and the electrostatic latent image is developed with toner by the developing means (104). The toner development is transferred to the transfer body (105) by the transfer means (106), and printed. Be out. Next, the surface of the photoconductor after the image transfer is cleaned by a cleaning unit (107), and further neutralized by a neutralizing unit (not shown), and the above operation is repeated again.

The present invention provides a process cartridge for an image forming apparatus in which a photosensitive member having a smooth charge transporting surface cross-linked layer and at least one of charging, developing, transferring, cleaning, and neutralizing means are integrated.
As is apparent from the above description, the electrophotographic photosensitive member of the present invention is not only used in electrophotographic copying machines, but also in electrophotographic application fields such as laser beam printers, CRT printers, LED printers, liquid crystal printers, and laser plate making. Can also be used widely.

  Hereinafter, the present invention will be described in more detail by way of synthesis examples, examples and comparative examples, but the present invention is not limited to the following examples. Note that “parts” used in the examples all represent parts by weight.

<Synthesis Example of Radical Polymerizable Compound Having Charge Transporting Structure>
The compound having a charge transporting structure in the present invention is synthesized, for example, by the method described in Japanese Patent No. 3164426. An example of this is shown below.
Synthesis Example of Radical Polymerizable Compound Having Triarylamine Structure (1) Synthesis of Hydroxy Group-Substituted Triarylamine Compound (Structural Formula B below) Methoxy group-substituted triarylamine compound (Structural Formula A below) 113.85 g (0 0.3 mol) and 138 g (0.92 mol) of sodium iodide were added with 240 ml of sulfolane and heated to 60 ° C. in a nitrogen stream. In this solution, 99 g (0.91 mol) of trimethylchlorosilane was added dropwise over 1 hour and stirred at a temperature of about 60 ° C. for 4 and a half hours to complete the reaction. About 1.5 L of toluene was added to the reaction solution, cooled to room temperature, and washed repeatedly with water and an aqueous sodium carbonate solution. Thereafter, the solvent was removed from the toluene solution and purified by column chromatography (adsorption medium: silica gel, developing solvent: toluene: ethyl acetate = 20: 1). Cyclohexane was added to the obtained pale yellow oil to precipitate crystals. In this way, 88.1 g (yield = 80.4%, melting point: 64.0-66.0 ° C.) of the white crystal of the following structural formula B was obtained. The elemental analysis results are shown below.

(2) Synthesis of Triarylamino Group-Substituted Acrylate Compound (Exemplary Compound No. 54) 82.9 g (0.227 mol) of the hydroxy group-substituted triarylamine compound (Structural Formula B) obtained in (1) above was added to 400 ml of tetrahydrofuran. In a nitrogen stream, an aqueous sodium hydroxide solution (NaOH: 12.4 g, water: 100 ml) was added dropwise. The solution was cooled to 5 ° C., and 25.2 g (0.272 mol) of acrylic acid chloride was added dropwise over 40 minutes. Then, it stirred at 5 degreeC for 3 hours, and reaction was complete | finished. The reaction solution was poured into water and extracted with toluene. This extract was repeatedly washed with an aqueous sodium bicarbonate solution and water. Thereafter, the solvent was removed from the toluene solution and purified by column chromatography (adsorption medium: silica gel, developing solvent: toluene). N-Hexane was added to the obtained colorless oil to precipitate crystals. Thus, Exemplified Compound NO. As a result, 80.73 g of 54 white crystals (yield = 84.8%, melting point: 117.5 to 119.0 ° C.) was obtained. The elemental analysis results are shown below.

Synthesis example of acrylic ester compound (1) Preparation of diethyl 2-hydroxybenzylphosphonate 38.4 g of 2-hydroxybenzyl alcohol (manufactured by Tokyo Chemical Industry Co., Ltd.) in a reaction vessel equipped with a stirrer, thermometer and dropping funnel, o -80 ml of xylene was added, 62.8 g of triethyl phosphite (manufactured by Tokyo Chemical Industry Co., Ltd.) was slowly added dropwise at 80 ° C under a nitrogen stream, and the reaction was further carried out at the same temperature for 1 hour. Thereafter, the produced ethanol, the solvent o-xylene, and unreacted triethyl phosphite were removed by distillation under reduced pressure to obtain 66 g of diethyl 2-hydroxybenzylphosphonate. (Boiling point: 120.0 ° C./1.5 mmHg) (Yield 90%)

(2) Preparation of 2-hydroxy-4 ′-(N, N-bis (4-methylphenyl) amino) stilbene Into a reaction vessel equipped with a stirrer, thermometer and dropping funnel, 14.8 g of potassium tert-butoxide. A solution of 9.90 g of diethyl 2-hydroxybenzylphosphonate and 5.44 g of 4- (N, N-bis (4-methylphenyl) amino) benzaldehyde in tetrahydrofuran was added under a nitrogen stream. The solution was slowly added dropwise at room temperature, and then reacted at the same temperature for 2 hours. Thereafter, water was added under water cooling, and then 2N hydrochloric acid aqueous solution was added for acidification. Tetrahydrofuran was removed by an evaporator, and the crude product was extracted with toluene. The toluene phase was washed with water, an aqueous sodium hydrogen carbonate solution and saturated brine in this order, and dehydrated by adding magnesium sulfate. After filtration, toluene was removed to obtain an oily crude product, which was further purified with silica gel and then crystallized in hexane to give 5.09 g of 2-hydroxy-4 ′-(N, N-bis). (4-Methylphenyl) amino) stilbene was obtained. (Yield 72%, melting point 136.0-138.0 ° C.)

(3) Preparation of 4 ′-(N, N-bis (4-methylphenyl) amino) stilben-2-yl acrylate In a reaction vessel equipped with a stirrer, thermometer and dropping funnel, 2-hydroxy-4′- (N, N-bis (4-methylphenyl) amino) stilbene (14.9 g), tetrahydrofuran (100 ml), 12% strength aqueous sodium hydroxide solution (21.5 g) were added, and acrylic acid chloride (5.17 g) was added at 5 ° C. under a nitrogen stream. It was added dropwise over 30 minutes. Then, it was made to react at the same temperature for 3 hours. The reaction solution was poured into water, extracted with toluene, concentrated and subjected to column purification with silica gel. The obtained crude product was recrystallized with ethanol, and yellow needle-like 4 ′-(N, N-bis (4-methylphenyl) amino) stilben-2-yl acrylate (Exemplary Compound NO. 109) 13. 5 g was obtained. (Yield 79.8%, melting point 104.1-105.2 ° C.) Elemental analysis results are shown below.

以上の様に、２−ヒドロキシベンジルホスホン酸エステル誘導体と種々のアミノ置換ベンズアルデヒド誘導体を反応させることにより数多くの２−ヒドロキシスチルベン誘導体を合成し、そのアクリル化またはメタクリル化を行なうことで種々のアクリル酸エステル化合物を合成することができる。

As described above, a number of 2-hydroxystilbene derivatives are synthesized by reacting 2-hydroxybenzylphosphonic acid ester derivatives with various amino-substituted benzaldehyde derivatives, and acrylation or methacrylation is carried out to produce various acrylic acids. An ester compound can be synthesized.

Example 1
By coating an undercoating layer coating solution, a charge generation layer coating solution, and a charge transporting layer coating solution in the following composition on a φ100 mm aluminum cylinder sequentially by a dip coating method and drying, A 3.0 μm undercoat layer, a 0.2 μm charge generation layer, and a 20 μm charge transport layer were formed.
[Coating liquid for undercoat layer]
-Alkyd resin: 6 parts (Beccosol 1307-60-EL, 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]
-Titanyl phthalocyanine pigment of the following structural formula (I): 15 parts-Polyvinyl butyral (BX-1: manufactured by Sekisui Chemical): 10 parts-2-butanone: 280 parts

[Coating fluid for charge transport layer]
-Bisphenol Z polycarbonate: 10 parts (Panlite TS-2050, manufactured by Teijin Chemicals)
-Low molecular charge transport material of the following structural formula (II): 7 parts-Tetrahydrofuran: 100 parts-Tetrahydrofuran solution of 1% silicone oil: 0.2 parts (KF50-100CS, manufactured by Shin-Etsu Chemical Co., Ltd.)

電荷輸送層上に下記構成の架橋表面層用塗工液をスプレーにより塗布し、紫外線照射により硬化させた後、乾燥して電子写真感光体を得た。架橋表面層塗工液の組成を以下に示す。

A coating solution for a crosslinked surface layer having the following constitution was applied on the charge transport layer by spraying, cured by ultraviolet irradiation, and dried to obtain an electrophotographic photoreceptor. The composition of the crosslinked surface layer coating solution is shown below.

[Coating liquid for cross-linked surface layer]
-Radical polymerizable compound having a charge transporting structure: 10 parts Example Compound NO. 54 (Molecular weight: 419, number of functional groups: 1)
・ Trifunctional or higher-functional radical polymerizable monomer having no charge transport structure: 10 parts Trimethylolpropane triacrylate (manufactured by Nippon Kayaku, KAYARAD TMPTA, molecular weight: 296, number of functional groups: trifunctional)
Photopolymerization initiator: 1 part Irgacure 184 (manufactured by Nippon Kayaku, molecular weight: 204)
Solvent: 120 parts Tetrahydrofuran (boiling point: 66 ° C., saturated vapor pressure: 176 mmHg / 25 ° C.)

After spray coating, UV irradiation was performed while rotating a support of Φ = 100 mm at 30 rpm using a UV lamp system manufactured by Fusion, a UV irradiation device. For the ultraviolet irradiation, a metal halide lamp was used, the distance between the ultraviolet lamp and the surface of the photoconductor was 53 mm, the illuminance was 800 mW / cm ^2, and the ultraviolet ray was irradiated for 90 seconds to cure the coating film. A temperature control apparatus as shown in FIG. 2 was used for temperature control. A cylindrical elastic body made of Maruyoshi Polymer Co., Ltd. ethylene propylene diene rubber (EPDM) was used. Temperature control is performed under the following conditions, and the temperature rise after 30 seconds of irradiation is 28 ° C. starting temperature measured at a position just opposite to the UV lamp position (a position that is 180 ° different from the UV lamp) across the support. Ultraviolet irradiation was carried out at 10 ° C., an ultimate temperature of 42 ° C., and an irradiation amount of 72 J / cm ² .
Refrigerant: Water refrigerant temperature: 25 ° C
Refrigerant pressure: 0.15 Mpa
Circulation flow rate: 5 L / min Cylindrical elastic body thickness: 0.5 mm
After the ultraviolet irradiation, drying was performed at 100 ° C. for 10 minutes, and a crosslinked surface layer having a thickness of 8 μm was provided to obtain the electrophotographic photosensitive member of the present invention.

(Example 2)
In Example 1, all except that the refrigerant temperature was 24 ° C., the irradiation time was 120 seconds, the start temperature was 27 ° C., the temperature increase after 30 seconds of irradiation was 10 ° C., the reached temperature was 42 ° C., and the irradiation amount was 96 J / cm ^2. The electrophotographic photoreceptor of the present invention was obtained in the same manner as Example 1.

(Example 3)
In Example 1, all except that the refrigerant temperature was 23 ° C., the irradiation time was 145 seconds, the start temperature was 26 ° C., the temperature increase after 30 seconds of irradiation was 10 ° C., the reached temperature was 42 ° C., and the irradiation amount was 116 J / cm ^2. The electrophotographic photoreceptor of the present invention was obtained in the same manner as Example 1.

Example 4
In Example 1, the thickness of the cylindrical elastic body is 1.0 mm, the refrigerant temperature is 25 ° C., the irradiation time is 90 seconds, the start temperature is 28 ° C., the temperature rise after 30 seconds is 11 ° C., the reached temperature is 46 ° C. An electrophotographic photosensitive member of the present invention was obtained in the same manner as in Example 1 except that the amount was 72 J / cm ² .

(Example 5)
In Example 1, the thickness of the cylindrical elastic body is 1.0 mm, the refrigerant temperature is 24 ° C., the irradiation time is 120 seconds, the start temperature is 27 ° C., the temperature rise after 30 seconds is 11 ° C., the reached temperature is 46 ° C. An electrophotographic photosensitive member of the present invention was obtained in the same manner as in Example 1 except that the amount was 96 J / cm ² .

(Example 6)
In Example 1, the cylindrical elastic body thickness is 1.0 mm, the refrigerant temperature is 22 ° C., the irradiation time is 150 seconds, the starting temperature is 25 ° C., the temperature rise after 30 seconds is 11 ° C., the reached temperature is 46 ° C. An electrophotographic photoreceptor of the present invention was obtained in the same manner as in Example 1 except that the amount was 120 J / cm ² .

(Example 7)
In Example 1, the thickness of the cylindrical elastic body is 1.5 mm, the refrigerant temperature is 24 ° C., the irradiation time is 120 seconds, the start temperature is 27 ° C., the temperature rise after 30 seconds is 12 ° C., the ultimate temperature is 51 ° C. An electrophotographic photosensitive member of the present invention was obtained in the same manner as in Example 1 except that the amount was 96 J / cm ² .

(Example 8)
In Example 1, the thickness of the cylindrical elastic body is 1.5 mm, the refrigerant temperature is 28 ° C., the irradiation time is 110 seconds, the start temperature is 30 ° C., the temperature rise after 30 seconds is 12 ° C., the ultimate temperature is 54 ° C. An electrophotographic photoreceptor of the present invention was obtained in the same manner as in Example 1 except that the amount was 88 J / cm ² .

Example 9
In Example 1, the thickness of the cylindrical elastic body is 1.5 mm, the refrigerant temperature is 32 ° C., the irradiation time is 70 seconds, the start temperature is 34 ° C., the temperature rise after 30 seconds is 12 ° C., the ultimate temperature is 54 ° C. An electrophotographic photosensitive member of the present invention was obtained in the same manner as in Example 1 except that the amount was 56 J / cm ² .

(Example 10)
In Example 1, the cylindrical elastic body thickness is 2.0 mm, the refrigerant temperature is 28 ° C., the irradiation time is 110 seconds, the start temperature is 30 ° C., the temperature rise after 30 seconds of irradiation is 13 ° C., the ultimate temperature is 58 ° C. An electrophotographic photoreceptor of the present invention was obtained in the same manner as in Example 1 except that the amount was 88 J / cm ² .

(Example 11)
In Example 1, the thickness of the cylindrical elastic body is 2.0 mm, the refrigerant temperature is 26 ° C., the irradiation time is 180 seconds, the start temperature is 28 ° C., the temperature rise after 30 seconds of irradiation is 13 ° C., the ultimate temperature is 58 ° C. An electrophotographic photosensitive member of the present invention was obtained in the same manner as in Example 1 except that the amount was 144 J / cm ² .

Example 12
In Example 1, the cylindrical elastic body thickness is 1.5 mm, the refrigerant temperature is 20 ° C., the irradiation time is 120 seconds, the starting temperature is 22 ° C., the temperature rise after 30 seconds of irradiation is 12 ° C., the reached temperature is 46 ° C. An electrophotographic photosensitive member of the present invention was obtained in the same manner as in Example 1 except that the amount was 96 J / cm ² .

(Comparative Example 1)
In Example 1, a temperature control device was used in which the temperature control device controls the temperature by directly flowing water, which is a coolant, inside the cylindrical base. Example 1 except that the refrigerant temperature was 20 ° C., the irradiation time was 150 seconds, the starting temperature was 22 ° C., the temperature increase after 30 seconds of irradiation was 6 ° C., the reached temperature was 35 ° C., and the irradiation amount was 150 J / cm ^2. In the same manner as above, an electrophotographic photoreceptor was obtained.

(Comparative Example 2)
Using the same temperature control device as in Comparative Example 1, the refrigerant temperature was 24 ° C., the irradiation time was 120 seconds, the start temperature was 26 ° C., the temperature increase after 30 seconds of irradiation was 6 ° C., the reached temperature was 38 ° C., and the irradiation amount was An electrophotographic photoreceptor was obtained in the same manner as in Example 1 except that the density was 96 J / cm ² .

(Comparative Example 3)
Using the same temperature control device as in Comparative Example 1, the refrigerant temperature was 32 ° C., the irradiation time was 120 seconds, the start temperature was 34 ° C., the temperature increase after 30 seconds of irradiation was 6 ° C., the reached temperature was 46 ° C., and the irradiation amount was An electrophotographic photoreceptor was obtained in the same manner as in Example 1 except that the density was 96 J / cm ² .

(Comparative Example 4)
In Example 1, the thickness of the cylindrical elastic body is 0.5 mm, the refrigerant temperature is 20 ° C., the irradiation time is 120 seconds, the start temperature is 22 ° C., the temperature rise after 30 seconds of irradiation is 10 ° C., the temperature reached is 37 ° C. An electrophotographic photosensitive member of the present invention was obtained in the same manner as in Example 1 except that the amount was 96 J / cm ² .

(Comparative Example 5)
In Example 1, the thickness of the cylindrical elastic body is 2.0 mm, the refrigerant temperature is 32 ° C., the irradiation time is 120 seconds, the starting temperature is 34 ° C., the temperature rise after 30 seconds of irradiation is 13 ° C., the temperature reached 63 ° C. An electrophotographic photosensitive member of the present invention was obtained in the same manner as in Example 1 except that the amount was 96 J / cm ² .

(Comparative Example 6)
In Example 1, without using a temperature control device, ultraviolet rays were irradiated while rotating the cylindrical substrate, the irradiation time was 60 seconds, the starting temperature was 20 ° C., the temperature increase after 30 seconds of irradiation was 28 ° C., and the temperature reached An electrophotographic photosensitive member of the present invention was obtained in the same manner as in Example 1 except that the temperature was 95 ° C. and the irradiation amount was 48 J / cm ² .

(Comparative Example 7)
In Example 1, without using a temperature control device, ultraviolet rays were irradiated while rotating the cylindrical substrate, the irradiation time was 120 seconds, the starting temperature was 20 ° C., the temperature increase after 30 seconds of irradiation was 28 ° C., and the temperature reached An electrophotographic photoreceptor of the present invention was obtained in the same manner as in Example 1 except that the temperature was 138 ° C. and the irradiation amount was 48 J / cm ² .

(Comparative Example 8)
In Example 1, temperature control was performed by applying cold air of 10 ° C. to the cylindrical substrate from the outside. Except that the irradiation time is 120 seconds, the starting temperature is 10 ° C., the temperature rise after 30 seconds of irradiation is 18 ° C., the ultimate temperature is 85 ° C., and the irradiation amount is 96 J / cm ² , while rotating the cylindrical substrate. The electrophotographic photoreceptor of the present invention was obtained in the same manner as in Example 1.

(Comparative Example 9)
In Example 1, an electrophotographic photosensitive member was obtained in the same manner as in Example 1 except that the thickness of the charge transport layer was 28 μm and no surface layer was provided.

  The photoconductor produced as described above was subjected to a 100,000 sheets (A4) paper passing test using Rigoh's Imagio MF1350. In the present invention, the initial portion and the exposed portion potential after fatigue and paper passing, the measurement of the wear amount, and the image evaluation were performed. The amount of wear due to paper passing was calculated by measuring the film thickness of the photoreceptor before and after paper passing using an eddy current film thickness measuring device (manufactured by Fischer Instruments). Table 5 shows the temperature measurement results and the irradiation amount during ultraviolet irradiation. Table 6 shows the results of the paper passing test.

画像評価：○良好、△若干濃度低下、×濃度低下が著しい

Image evaluation: ○ Good, △ Slight decrease in density, X

  From the results of the actual machine paper passing test, Examples 1 to 12 of the present invention have little decrease in electrical characteristics after paper passing and no abnormal images. Moreover, the amount of wear is small and the wear resistance is improved. On the other hand, in Comparative Examples 1 to 9, the electrical characteristics after passing are markedly decreased, or the amount of wear is large, so that image stability over a long period of time and high durability of the photoreceptor cannot be expected.

(Example 13)
Using the electrophotographic photosensitive member of Example 5, an additional 900,000 sheets were tested. As a result, even after passing 1 million sheets, the electrical characteristics did not deteriorate and no abnormal image occurred. In addition, the amount of wear after passing 1 million sheets was 2.2 μm, and high wear resistance was confirmed even in long-term use.

Therefore, in a method for producing an electrophotographic photosensitive member having a photosensitive layer and a surface layer on a conductive support, the surface layer has a step of forming a crosslinked resin film by being cured by irradiating ultraviolet rays. The temperature rise on the surface of the photoconductor from the start of irradiation during ultraviolet irradiation to 30 seconds is 10 ° C. or higher, and the temperature reached on the surface of the photoconductor at the end of irradiation is controlled to 40 ° C. or higher and 60 ° C. or lower. The electrophotographic photosensitive member manufactured by the method of manufacturing an electrophotographic photosensitive member characterized by the above has realized an electrophotographic photosensitive member having good electrical characteristics and high durability and capable of maintaining a high-quality image.
Further, it has been clarified that the image forming process, the image forming apparatus, and the process cartridge for the image forming apparatus using the photoconductor of the present invention have high performance and high reliability.

It is a figure which shows the relationship between ultraviolet irradiation time and a photoreceptor surface temperature. It is a conceptual diagram of the temperature control apparatus used by this invention. 1 is an example of a cross-sectional view of an electrophotographic photosensitive member of the present invention. It is another example of sectional drawing of the electrophotographic photosensitive member of this invention. 1 is a schematic diagram illustrating an example of an image forming apparatus of the present invention. FIG. 2 is a schematic diagram illustrating an example of a process cartridge for an image forming apparatus according to the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Photoconductor 2 Static elimination lamp 3 Charger 4 Eraser 5 Image exposure part 6 Developing unit 7 Pre-transfer charger 8 Registration roller 9 Transfer body 10 Transfer charger 11 Separation charger 12 Separation claw 13 Pre-cleaning charger 14 Fur brush 15 Cleaning blade 31 Conductivity Support 33 Photosensitive layer 35 Charge generation layer 37 Charge transport layer 51 Cylindrical substrate 52 Ultraviolet lamp 54 Cylindrical elastic body 59 Refrigerant supply pipe 101 Photoconductor 102 Charging means 103 Exposure means 104 Developing means 105 Transfer body 106 Transfer means 107 Cleaning means (Cleaning blade)

Claims (11)

In the method for producing an electrophotographic photosensitive member having a photosensitive layer and a surface layer on a conductive support, the surface layer is cured by irradiating ultraviolet rays to form a crosslinked resin film. The temperature rise of the photoreceptor surface from the start of irradiation during ultraviolet irradiation to 30 seconds is 10 ° C. or more, and the temperature reached on the photoreceptor surface at the end of irradiation is controlled to 40 ° C. or more and 60 ° C. or less. A method for producing an electrophotographic photosensitive member. The method for producing an electrophotographic photosensitive member according to claim 1, wherein the irradiation amount of the ultraviolet is 70 J / cm ² or more 120 J / cm ² or less. The method for producing an electrophotographic photosensitive member according to claim 1, wherein an initial temperature of the surface of the photosensitive member before ultraviolet irradiation is 30 ° C. or less. The conductive support is a cylindrical base body, and has a cylindrical elastic body that contacts the entire inner surface of the cylindrical base body as temperature control means for controlling the temperature, and is provided inside the cylindrical elastic body. 4. The method for producing an electrophotographic photosensitive member according to claim 1, wherein a temperature control device is used which introduces a liquid as a refrigerant and suppresses a temperature rise of the cylindrical substrate to control the temperature. . The method for producing an electrophotographic photosensitive member according to claim 4, wherein the cylindrical elastic body swells due to a pressure of a liquid used as a refrigerant and adheres closely to an inner surface of the cylindrical substrate. 6. The method for producing an electrophotographic photosensitive member according to claim 4, wherein the cylindrical elastic body has a thickness of 0.5 mm to 3.0 mm. The crosslinked resin film is
(B) Cured and formed by irradiating ultraviolet rays onto a monomer mixture containing a tri- or higher functional radical polymerizable monomer having no charge transport structure and (b) a radical polymerizable compound having a charge transport structure. The method for producing an electrophotographic photosensitive member according to any one of claims 1 to 6. An electrophotographic photosensitive member manufactured using the method for manufacturing an electrophotographic photosensitive member according to claim 1. 9. An image forming method, wherein at least charging, image exposure, development and transfer are repeated using the electrophotographic photosensitive member according to claim 8. An image forming apparatus comprising the electrophotographic photosensitive member according to claim 8. 9. An electrophotographic photosensitive member according to claim 8, and at least one means selected from the group consisting of a charging means, a developing means, a transfer means, a cleaning means, and a charge eliminating means, and is attachable to and detachable from an image forming apparatus main body. A process cartridge for an image forming apparatus.

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