JP2007322867A - Electrophotographic photoreceptor and method of manufacturing the same, and image forming method, image forming apparatus and process cartridge - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electrophotographic photoreceptor having a high-durability surface layer excellent in smoothness, having high wear resistance and good electrical characteristics, and capable of achieving higher image quality over a long period of time, a method of manufacturing the electrophotographic photoreceptor, and an image forming method, an image forming apparatus and a process cartridge using the electrophotographic photoreceptor. <P>SOLUTION: The electrophotographic photoreceptor comprises a support and at least a photosensitive layer and the surface layer disposed in this order on the support, wherein the surface layer contains a cured product obtained by curing a trifunctional or higher radical polymerizable compound having no charge transporting structure and a radical polymerizable compound having a charge transporting structure by photoirradiation, and an initial surface temperature of the electrophotographic photoreceptor at the beginning of photoirradiation is 10-25°C. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an electrophotographic photosensitive member (hereinafter referred to as “photosensitive member”, “electrostatic latent image carrier”, “image carrier”) having high wear resistance, high durability, and good electrical characteristics. And an image forming method, an image forming apparatus, and a process cartridge capable of realizing high image quality over a long period of time using the electrophotographic photosensitive member.

In recent years, organic photoconductors (OPCs) are used in many cases in copying machines, facsimile machines, laser printers, or complex machines in place of inorganic photoconductors. Reasons for this are, for example, (1) optical characteristics such as light absorption wavelength range and absorption amount, (2) electrical characteristics such as high sensitivity and stable charging characteristics, and (3) material selection range. These include wide area, (4) ease of production, (5) low cost, and (6) non-toxicity.
Recently, the diameter of the electrophotographic photosensitive member has been reduced due to the downsizing of the image forming apparatus, and the high durability of the photosensitive member has been eagerly desired in addition to the speeding up of the machine and the maintenance-free movement. The organophotoreceptor is generally soft because the surface layer is mainly composed of a low molecular charge transport material and an inert polymer, and when it is repeatedly used in an electrophotographic process, it is caused by a mechanical load caused by a development system and a cleaning system. There is a drawback that wear tends to occur. In addition, due to the demand for higher image quality, the rubber hardness of the cleaning blade and the contact pressure must be increased for the purpose of improving the cleaning property as the toner particle size is reduced. This also promotes the wear of the photoreceptor. It is a factor. Such wear of the photoreceptor deteriorates electrical characteristics such as sensitivity deterioration and chargeability, and causes abnormal images such as image density reduction and background stains. Furthermore, scratches where wear has occurred locally cause streak-like stain images due to poor cleaning. As a result, at present, the life of the electrophotographic photosensitive member is limited by the above-described wear and scratches and has been replaced.

In order to increase the durability of the electrophotographic photosensitive member, it is a first problem to reduce the wear amount of the photosensitive layer. Examples of techniques for improving the abrasion resistance of such a photosensitive layer include (1) using a curable binder for the surface layer (see Patent Document 1), and (2) a polymeric charge transport material for the photosensitive layer. (See Patent Document 2), (3) those in which an inorganic filler is dispersed in the surface layer (see Patent Document 3), and the like. Since the photoconductor using the curable binder (1) has poor compatibility with the charge transport material, the residual potential is increased due to impurities such as a polymerization initiator and an unreacted residue, and the image density is likely to decrease. Tend. In addition, the photoconductor using the polymer type charge transport material (2) can sufficiently improve the wear resistance, but sufficiently satisfies the durability required for the organic photoconductor. It has not yet reached. In addition, since polymer charge transport materials are difficult to polymerize and purify, and it is difficult to obtain high-purity materials, it is difficult to stabilize the electrical characteristics between materials, and the coating liquid has a high viscosity. It can cause problems. In addition, the photoconductor in which the inorganic filler (3) is dispersed exhibits higher wear resistance than a photoconductor in which a normal low molecular charge transport material is dispersed in an inert polymer. The residual potential increases due to the trap existing on the surface, and the image density tends to decrease. Further, when the unevenness of the inorganic filler and the binder resin on the surface of the photoreceptor is large, a cleaning failure occurs, which causes toner filming and image flow. The technologies (1), (2), and (3) sufficiently satisfy the overall durability including the electrical durability and mechanical durability required for the organic photoreceptor. It has not reached.
In order to improve the electrical characteristics of (1), there has been proposed a photoreceptor provided with a protective layer containing a conductive filler (see Patent Document 4). Although this photoreceptor can suppress an increase in residual potential due to repeated use, the resistance of the protective layer is low, so that the resolution tends to decrease and the image flow tends to occur in a high humidity environment.

  As a technique for improving the abrasion resistance of a photosensitive layer that replaces these, charge transport containing a monomer having a carbon-carbon double bond, a charge transporting material having a carbon-carbon double bond, and a cured product obtained by curing a binder resin A photoreceptor provided with a layer has been proposed (see Patent Document 5). The proposed binder resin includes those having a carbon-carbon double bond and having reactivity with respect to the charge transport material, and those having no double bond and not having reactivity. The proposed photoreceptor is noticeable because it has both wear resistance and good electrical characteristics. However, when a non-reactive binder resin is used, the photoconductor is a cured product produced by a reaction between the binder resin, a monomer having a carbon-carbon double bond, and a charge transport material. Causes poor phase compatibility in the cross-linked surface layer, resulting in locally low wear resistance, which causes damage to the surface of the photoconductor and adhesion of external toner additives and paper dust. It may become. When such fixing further proceeds, toner filming is caused, and there is a possibility that white spots of an image portion may occur due to non-uniformity of light transmission. In addition to the binder resin preventing the curing of the monomer, what is specifically described as the above monomer is bifunctional, and such a bifunctional monomer has a small number of functional groups and a sufficient crosslinking density is obtained. It was not yet satisfactory in terms of wear resistance. On the other hand, when a reactive binder is used, it is difficult to achieve both the binding amount of the charge transport material and the crosslinking density because of the low number of functional groups contained in the monomer and the binder resin, and the electrical characteristics and resistance. Abrasion was not sufficient.

  In addition, a photoreceptor having a photosensitive layer containing a compound obtained by curing a hole transporting compound having two or more chain polymerizable functional groups in the same molecule has been proposed (see Patent Document 6). The proposed photosensitive layer has a high hardness because it can increase the crosslink density, but the bulky hole transporting compound has two or more chain-polymerizable functional groups, so that distortion occurs in the cured product. The curing reaction tends to be uneven. For this reason, the restoring force with respect to external stress falls locally, and cracks and scratches may occur due to stress such as carrier adhesion due to repeated use over a long period of time.

In addition to the materials, there are curing conditions as a factor for improving the crosslinking density. In particular, it is disclosed that the surface temperature of the photoconductor during light irradiation greatly affects the characteristics of the photoconductor (see Patent Document 7). In this patent document 7, as the curing condition, the photoconductor surface temperature is controlled to 25 ° C. or higher and 130 ° C. or lower, and curing by light irradiation is performed. During photopolymerization, the surface of the photoconductor is heated to increase the mobility of the radically polymerized compound, and the reaction rate is lowered, improving the probability of polymerization of unreacted substances in the second half of the reaction, and finally achieving extremely high crosslinking. It is possible to build density.
However, the reaction rate due to photopolymerization differs between the outermost surface and the inside of the photoconductor, and the reaction rate of the outermost surface is larger than that of the inner surface. However, there is a problem that the reaction on the outermost surface proceeds very quickly as compared with the inside, and wrinkles are generated on the surface to adversely affect the film characteristics.

JP 56-48637 A JP-A 64-1728 JP-A-4-281461 JP 2002-6526 A Japanese Patent No. 3194392 JP 2000-66425 A JP 2001-125297 A

  An object of the present invention is to solve the conventional problems in response to the above-mentioned demands and achieve the following object. That is, the present invention provides an electrophotographic photoreceptor having a smooth and highly durable surface layer, high wear resistance, and good electrical characteristics, a method for producing the electrophotographic photoreceptor, and the electron An object of the present invention is to provide an image forming method, an image forming apparatus, and a process cartridge capable of forming a high-quality image over a long period of time using a photographic photoreceptor.

Means for solving the problems are as follows. That is,
<1> An electrophotographic photosensitive member having a support and at least a photosensitive layer and a surface layer in this order on the support,
The surface layer contains a cured product obtained by curing a radically polymerizable compound having a trifunctional or higher functionality not having a charge transporting structure and a radically polymerizable compound having a charge transporting structure by light irradiation,
An electrophotographic photosensitive member, wherein an initial surface temperature of the electrophotographic photosensitive member at the start of light irradiation is 10 ° C. or higher and 25 ° C. or lower.
<2> The electrophotographic photosensitive member according to <1>, wherein the maximum surface temperature of the electrophotographic photosensitive member during light irradiation is 40 ° C. or higher and 140 ° C. or lower.
<3> The electrophotographic photosensitive member according to any one of <1> to <2>, wherein the surface temperature of the electrophotographic photosensitive member is controlled by bringing a cooling means into contact with the inner side of the electrophotographic photosensitive member.
<4> The electrophotographic photosensitive member according to <3>, wherein the cooling unit is a unit that introduces a refrigerant whose temperature is controlled in an external thermostat into the mandrel tube and circulates the refrigerant between the thermostat. .
<5> The electrophotographic photosensitive member according to <4>, wherein the refrigerant is any one of water and silicone oil.
<6> The electrophotographic photosensitive member according to any one of <1> to <5>, wherein the photosensitive layer contains at least a charge generating substance, and the charge generating substance contains titanyl phthalocyanine.
<7> Titanyl phthalocyanine has a major peak at a Bragg angle 2θ of at least 9.6 ° ± 0.2 °, 24.0 ° ± 0.2 °, and 27.2 ° in an X-ray diffraction spectrum with respect to Cu—Kα ray. The electrophotographic photosensitive member according to <6>, wherein the electrophotographic photosensitive member has a crystal type of ± 0.2 °.
<8> The electrophotographic photosensitive member according to any one of <1> to <7>, wherein the photosensitive layer has a multilayer structure having at least a charge generation layer and a charge transport layer in this order.
<9> A method for producing an electrophotographic photosensitive member having at least a photosensitive layer and a surface layer in this order on a support,
Including at least a surface layer forming step of forming a surface layer by curing a radically polymerizable compound having three or more functional groups having no charge transporting structure and a radical polymerizable compound having a charge transporting structure by light irradiation;
An electrophotographic photosensitive member manufacturing method, wherein an initial surface temperature of the electrophotographic photosensitive member at the start of light irradiation is 10 ° C. or higher and 25 ° C. or lower.
<10> The method for producing an electrophotographic photosensitive member according to <9>, wherein the maximum surface temperature of the electrophotographic photosensitive member during light irradiation is 40 ° C. or higher and 140 ° C. or lower.
<11> The method for producing an electrophotographic photosensitive member according to any one of <9> to <10>, wherein an inner surface of the electrophotographic photosensitive member is brought into contact with a cooling unit to control a surface temperature of the electrophotographic photosensitive member. .
<12> The production of the electrophotographic photosensitive member according to <11>, wherein the cooling unit is a unit that introduces a refrigerant whose temperature is controlled in an external thermostat into the mandrel tube and circulates the refrigerant between the thermostat. Is the method.
<13> The method for producing an electrophotographic photosensitive member according to <12>, wherein the refrigerant is any one of water and silicone oil.
<14> The electrophotographic photosensitive member according to any one of <1> to <8>, an electrostatic latent image forming unit that forms an electrostatic latent image on the electrophotographic photosensitive member, and the electrostatic latent image At least development means for developing a visible image by using toner, transfer means for transferring the visible image to a recording medium, and fixing means for fixing the transfer image transferred to the recording medium An image forming apparatus characterized by the above.
<15> An electrostatic latent image forming step of forming an electrostatic latent image on the electrophotographic photosensitive member according to any one of <1> to <8>, and developing the electrostatic latent image with toner. An image forming method comprising: a developing step for forming a visible image in the image; a transfer step for transferring the visible image to a recording medium; and a fixing step for fixing the transferred image transferred to the recording medium. Is the method.
<16> Development for forming a visible image by developing the electrophotographic photosensitive member according to any one of <1> to <8> and an electrostatic latent image formed on the electrophotographic photosensitive member with toner. And a process cartridge that is detachable from the main body of the image forming apparatus.

The electrophotographic photosensitive member of the present invention has a support and at least a photosensitive layer and a surface layer in this order on the support, and the surface layer does not have a charge transporting structure and has a trifunctional or higher functional radical polymerization property. A cured product obtained by curing a compound and a radical polymerizable compound having a charge transporting structure by light irradiation;
When the initial surface temperature of the electrophotographic photosensitive member at the start of light irradiation is 10 ° C. or more and 25 ° C. or less, a surface layer having excellent smoothness can be obtained, and it has high durability and a long period of time. An electrophotographic photosensitive member capable of realizing high image quality can be provided. The following factors can be considered as the reason.
The surface temperature of the photoconductor rapidly rises due to light irradiation, but this temperature increase is necessary to complete the reaction by radical polymerization to the inside of the surface layer. 140 ° C. or lower. However, when the temperature is increased from the initial stage of light irradiation, the smoothness of the surface layer is impaired, and wrinkles, roughness, cloudiness, and the like are generated. The cause of this state is considered to be due to the difference in the reaction speed between the outermost surface of the photoreceptor and the inside during light irradiation. When the surface temperature of the photoreceptor becomes high, the molecular motion of the radical polymerization compound becomes active, and the photopolymerization reaction rate increases. However, the photopolymerization reaction rate is not the same in any part of the surface layer, and the photopolymerization reaction rate in the outermost surface part of the surface layer is much higher than that in the interior. As a result, the gap between the outermost surface and the internal curing rate is increased, and the smoothness of the surface layer is impaired. On the other hand, if the initial surface temperature at the start of light irradiation is less than 10 ° C., condensation may occur on the surface of the photoreceptor, and the smoothness of the surface layer may not be obtained.
Therefore, in the electrophotographic photoreceptor of the present invention, the gap between the outermost surface portion at the start of light irradiation and the internal reaction rate is reduced by setting the initial surface temperature at the start of light irradiation to 10 ° C. or more and 25 ° C. or less. The smoothness of the surface layer can be improved without impairing the durability of the layer.

The method for producing an electrophotographic photoreceptor of the present invention is a method for producing the electrophotographic photoreceptor of the present invention, comprising a trifunctional or higher functional radical polymerizable compound having no charge transport structure, and a charge transport structure. Comprising at least a surface layer forming step of forming a surface layer by curing the radically polymerizable compound with light irradiation;
Since the initial surface temperature of the electrophotographic photosensitive member at the start of light irradiation is 10 ° C. or more and 25 ° C. or less, it has a smooth and highly durable surface layer, high wear resistance, and good electrical properties. An electrophotographic photoreceptor having characteristics can be produced efficiently.

  The image forming apparatus of the present invention comprises the electrophotographic photosensitive member of the present invention, an electrostatic latent image forming unit for forming an electrostatic latent image on the electrostatic latent image carrier, and the electrostatic latent image with toner. The image forming apparatus includes at least a developing unit that forms a visible image by development, a transfer unit that transfers the visible image to a recording medium, and a fixing unit that fixes the transferred image transferred to the recording medium. In the image forming apparatus, the electrostatic latent image forming unit of the present invention forms an electrostatic latent image on the electrostatic latent image carrier. The developing means develops the electrostatic latent image with toner to form a visible image. The transfer means transfers the visible image to a recording medium. The fixing unit fixes the transferred image transferred to the recording medium. As a result, a high-quality electrophotographic image can be formed over a long period of time.

  The image forming method of the present invention includes an electrostatic latent image forming step of forming an electrostatic latent image on the electrostatic latent image carrier of the present invention, and developing the electrostatic latent image with toner to make it visible. It includes at least a developing step for forming an image, a transfer step for transferring the visible image to a recording medium, and a fixing step for fixing the transferred image transferred to the recording medium. In the image forming method, an electrostatic latent image is formed on the electrostatic latent image carrier of the present invention in the electrostatic latent image forming step. In the developing step, the electrostatic latent image is developed with toner to form a visible image. In the transfer step, the visible image is transferred to a recording medium. In the fixing step, the transferred image transferred to the recording medium is fixed. As a result, a high-quality electrophotographic image can be formed over a long period of time.

  The process cartridge of the present invention includes the electrostatic latent image carrier of the present invention, and a developing unit that develops the electrostatic latent image formed on the electrostatic latent image carrier with toner to form a visible image. At least. The process cartridge is detachable from the image forming apparatus, is highly convenient, and uses the electrophotographic photosensitive member of the present invention, so that a high-quality electrophotographic image can be formed over a long period of time.

  According to the present invention, conventional problems can be solved, the surface layer has excellent smoothness and high durability, high wear resistance, good electrical characteristics, and high image quality over a long period of time. Can be provided, an electrophotographic photoreceptor production method, an image forming method using the electrophotographic photoreceptor, an image forming apparatus, and a process cartridge.

(Electrophotographic photoreceptor)
The electrophotographic photoreceptor of the present invention comprises a support and at least a photosensitive layer and a surface layer in this order on the support, and further comprises other layers as necessary.

When forming the surface layer of the electrophotographic photosensitive member, the initial surface temperature of the electrophotographic photosensitive member at the start of light irradiation is 10 ° C. or more and 25 ° C. or less, preferably 13 to 22 ° C. If the initial surface temperature is less than 10 ° C, the smoothness of the surface layer may not be obtained due to the influence of moisture due to dew condensation. If the initial surface temperature exceeds 25 ° C, the smoothness of the surface layer may be impaired and wrinkles will occur. Roughness, cloudiness, etc. may occur.
The maximum surface temperature of the electrophotographic photosensitive member during light irradiation is preferably 40 ° C. or higher and 140 ° C. or lower, and more preferably 50 to 90 ° C. Within this range, a surface layer having excellent smoothness can be obtained, and an electrophotographic photosensitive member that has high durability and can realize high image quality over a long period of time can be obtained.
The maximum surface temperature during light irradiation means the highest surface temperature of the photoconductor during light irradiation, and the surface temperature of the photoconductor increases during light irradiation. It means the surface temperature of the photoreceptor at the end of irradiation.
Here, the surface temperature of the electrophotographic photoreceptor can be measured, for example, by bringing a thermocouple into contact with the surface of the photoreceptor opposite to the light irradiation surface.

  The method for controlling the surface temperature of the electrophotographic photosensitive member at the start of light irradiation and during light irradiation is not particularly limited, and many methods are conceivable. For example, (1) a method of flowing a temperature-controlled refrigerant such as gas or liquid directly inside a photosensitive drum as an electrophotographic photosensitive member, and (2) a cooling means having a large heat capacity is provided inside the photosensitive drum as an electrophotographic photosensitive member. Examples include a contact method, and (3) a temperature feedback control method.

In the method (1), the temperature can be adjusted by a relatively simple means. However, the method of flowing gas directly inside the photosensitive drum cannot sufficiently remove the heat energy due to light irradiation, and the photosensitive member. The surface temperature eventually exceeds 140 ° C., which may cause a residual potential increase and sensitivity deterioration. In the method of flowing a liquid instead of a gas, for example, water is used as the liquid. However, the temperature cannot be sufficiently increased, and the radical polymerization reaction may not be completed to the inside of the surface layer. Furthermore, it is necessary to treat the liquid after the light irradiation, and the production efficiency may be inferior.
Here, FIG. 4 is a diagram showing an example of a system in which the coolant is directly flowed into the photosensitive drum (1). In the method of FIG. 4, the photosensitive drum 202 is sandwiched between jigs 203 and 203 that chuck from both sides, the refrigerant 204 is poured from one side, and the refrigerant is poured out from the other side. Air, water, oil or the like is used as the refrigerant. This jig rotates the photosensitive drum 202 at a constant speed by the operation of a rotary motor (not shown).

As a method of bringing the member having a large heat capacity (2) into contact with the inner side of the photosensitive drum, for example, there is a method of controlling the surface temperature of the photosensitive member by bringing the inner side of the electrophotographic photosensitive member into contact with a cooling means. The means is not particularly limited as long as the refrigerant can be circulated therein, and can be appropriately selected according to the purpose. Examples thereof include a mandrel tube. The material, structure, shape, size, number, etc. of the mandrel tube are not particularly limited and can be appropriately selected according to the purpose. Specifically, a method of introducing water or silicone oil as a refrigerant by introducing a refrigerant whose temperature is controlled by an external thermostat into the mandrel tube and circulating it between the thermostat is used. According to this method, it is possible to increase the temperature at the time of light irradiation to a temperature necessary for completing radical polymerization while controlling the surface temperature of the photosensitive member at the start of light irradiation.
An electrophotographic photosensitive member can be produced efficiently by controlling the surface temperature of a plurality of photosensitive members using one long mandrel tube.

  In the method (3) based on feedback control, the temperature of the refrigerant circulating in the cooling means is set in advance, and if the set temperature is exceeded, the temperature of the refrigerant is adjusted or the flow rate of the refrigerant is adjusted. This is a method of adjusting and controlling the temperature of the refrigerant to be constant. The method (1) or (2) and the method (3) may be combined.

  Here, FIG. 1 is a diagram in which a photosensitive drum 202 as an electrophotographic photosensitive member is mounted on a mandrel tube 201. The photosensitive drum 202 is irradiated with light while rotating in the direction of the arrow in the figure. 2 and 3 are views showing the inside of the mandrel pipe 201. In FIG. 2, the refrigerant 210 is circulated from the lower part to the upper part of the mandrel pipe. In FIG. 3, the refrigerant 210 is circulated from the upper part to the lower part of the mandrel tube. The refrigerant to be circulated can be appropriately selected depending on the required temperature. Examples of the refrigerant include water, alcohols, fluorine-based inert liquids, ethylene glycol, and silicone oil. Among these, water and silicone oil are particularly preferable. As the refrigerant, an external thermostat (not shown) or the like is used, and the temperature can be controlled by circulating between the mandrel tube and the thermostat.

<Configuration of electrophotographic photoreceptor>
The electrophotographic photosensitive member of the present invention is not particularly limited with respect to the layer structure, and can be appropriately selected according to the purpose. Therefore, the following first form or second form is preferable.
In the first embodiment, the electrophotographic photosensitive member includes a support, a single-layer type photosensitive layer on the support, and a surface layer on the single-layer type photosensitive layer. And other layers.
Further, in the second embodiment, the electrophotographic photosensitive member has a support, a multilayer photosensitive layer having at least a charge generation layer and a charge transport layer in this order on the support, and the multilayer photosensitive layer. A surface layer and, if necessary, other layers. In the second embodiment, the charge generation layer and the charge transport layer may be laminated in reverse.

Here, the layer structure of the electrophotographic photosensitive member will be described with reference to the drawings.
FIG. 5 is a schematic cross-sectional view showing an example of the electrophotographic photosensitive member of the present invention. A photosensitive member having a single layer structure in which a photosensitive layer 233 having a charge generating function and a charge transporting function are provided on a support 231 at the same time. It is. In FIG. 5, 239 represents a surface layer.
FIG. 6 is a schematic sectional view showing another example of the electrophotographic photosensitive member of the present invention. On the support 231, a charge generation layer 235 having a charge generation function and a charge transport layer 237 having a charge transport material function are provided. Is a laminated photoconductor. In FIG. 6, 239 represents a surface layer.

<Surface layer>
The surface layer contains a trifunctional or higher functional radical polymerizable compound having no charge transporting structure and a cured product obtained by curing with irradiation of a radical polymerizable compound having a charge transport structure. It contains other components as necessary.

-Trifunctional or higher radical polymerizable compound having no charge transport structure-
The trifunctional or higher functional radical polymerizable compound having no charge transport structure is, for example, a hole transport structure such as triarylamine, hydrazone, pyrazoline, carbazole; condensed polycyclic quinone, diphenoquinone, cyano group, nitro group, etc. The compound has no electron transport structure such as an electron-withdrawing aromatic ring and has 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 can be radically polymerized.

  Examples of the tri- or higher functional radical polymerizable compound having no charge transport structure include (1) 1-substituted ethylene functional group or (2) 1,1-substituted ethylene functional group shown below. It is done.

(1) As 1-substituted ethylene functional group, the functional group represented by the following <Formula 1> is mentioned, for example.
<Formula 1>
CH ₂ = _{CH-X 1} -
However, in the above <Formula 1>, X ₁ represents an arylene group which may have a substituent such as a phenylene group or a naphthylene group; an alkenylene group which may have a substituent, a —CO— group, — COO— group, —CON (R ₁₀ ) — group (where R ₁₀ represents 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 or a naphthyl group) Represents an aryl group such as a group) or an S-group.
Examples of these substituents include a vinyl group, a styryl group, a 2-methyl-1,3-butadienyl group, a vinylcarbonyl group, an acryloyloxy group, an acryloylamino group, and a vinyl thioether group.

(2) Examples of the 1,1-substituted ethylene functional group include functional groups represented by the following <Formula 2>.
<Formula 2>
_{CH 2 = C (Y) -X} 2 -
However, in <Formula 2>, Y has a substituent such as an alkyl group which may have a substituent, an aralkyl group which may have a substituent, a phenyl group or a naphthyl group. Aryl group, halogen atom, cyano group, nitro group, methoxy group, ethoxy group and other alkoxy groups, -COOR ₁₁ group (where R ₁₁ is a hydrogen atom, a methyl group optionally having substituents, An alkyl group such as an ethyl group, an aralkyl group such as an optionally substituted benzyl or phenethyl group, an aryl group such as an optionally substituted phenyl group or naphthyl group, or CONR ₁₂ R ₁₃ ( However, R ₁₂ and R ₁₃ may be the same as each other or different, a hydrogen atom, which may have a substituent an alkyl group such as methyl group and an ethyl group, a benzyl group, Nafuchirume Le represents group, aralkyl group which may have a substituent such as a phenethyl group, or a phenyl group, a represents an aryl group which may have a substituent such as naphthyl group).
X ₂ represents the same substituent, single bond, or alkylene group as X _{1 in the} above <Formula 1>. Note that at least one of Y and X ₂ represents an oxycarbonyl group, a cyano group, an alkenylene group, or an aromatic ring.
Examples of these substituents include an α-acryloyloxy 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 substituting the substituent for X ₁ , X ₂ and Y include, for example, a halogen atom, a nitro group, a cyano group; an alkyl group such as a methyl group, an ethyl group; a methoxy group, an ethoxy group An alkoxy group such as a group; an aryloxy group such as a phenoxy group; an aryl group such as a phenyl group or a naphthyl group; an aralkyl group such as a benzyl group or a phenethyl group;
Among these radical polymerizable functional groups, an acryloyloxy group and a methacryloyloxy group are particularly preferable.
As the compound having three or more acryloyloxy groups, for example, a compound having three or more hydroxyl groups in the molecule and acrylic acid (salt), acrylic acid halide, acrylate ester, ester reaction or transesterification reaction Can be obtained. 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 from each other.

  The trifunctional or higher functional radical polymerizable compound having no charge transport structure is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include trimethylolpropane triacrylate (TMPTA) and trimethylolpropane. Trimethacrylate, trimethylolpropane alkylene-modified triacrylate, trimethylolpropane ethyleneoxy-modified (hereinafter sometimes referred to as “EO-modified”) triacrylate, trimethylolpropane propyleneoxy-modified (hereinafter referred to as “PO-modified”) A) triacrylate, trimethylolpropane caprolactone-modified triacrylate, trimethylolpropane alkylene-modified trimethacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate (PETTA), glycerol triacrylate, glycerol epichlorohydrin modified (hereinafter also referred to as “ECH modified”) triacrylate, glycerol EO modified triacrylate, glycerol PO modified triacrylate, tris (acryloxyethyl) Isocyanurate, dipentaerythritol hexaacrylate (DPHA), dipentaerythritol caprolactone-modified hexaacrylate, dipentaerythritol hydroxypentaacrylate, alkylated dipentaerythritol pentaacrylate, alkylated dipentaerythritol tetraacrylate, alkylated dipentaerythritol triacrylate , Dimethylolpropane tetraacrylate (DTMPTA), pentaerythritol ester Carboxy tetraacrylate, phosphoric acid EO-modified triacrylate, 2,2,5,5 etc. tetrahydroxy methyl cyclopentanone tetraacrylate and the like. These may be used individually by 1 type and may use 2 or more types together.

The trifunctional or higher functional radical polymerizable compound having no charge transport structure preferably has a functional group ratio (molecular weight / functional group number) of 250 or less in order to form a dense cross-linked bond in the surface layer. When the functional group ratio exceeds 250, the surface layer is soft and wear resistance is somewhat lowered. Therefore, among the monomers exemplified above, monomers having a modifying group such as EO, PO, and caprolactone are extremely long. It is not preferable to use one having a modifying group alone.
The content of the trifunctional or higher functional radical polymerizable compound not having the charge transporting structure is preferably 20 to 80% by mass, more preferably 30 to 70% by mass with respect to the total amount of the surface layer. When the content is less than 20% by mass, the surface layer has a small three-dimensional cross-linking density, and a dramatic improvement in wear resistance may not be achieved as compared with the case of using a conventional thermoplastic binder resin. If it exceeds 80% by mass, the content of the radically polymerizable compound having a charge transporting structure may be lowered, and the electrical characteristics may be deteriorated.

-Radical polymerizable compound with charge transport structure-
The radically polymerizable compound having a charge transporting structure is not particularly limited and may be appropriately selected depending on the intended purpose. However, the radically polymerizable compound having a monofunctional charge transporting structure and bifunctional charge transporting may be used. A radical polymerizable compound having a functional structure, a radical polymerizable compound having a trifunctional charge transporting structure, and the like. Among these, a radical polymerizable compound having a monofunctional charge transporting structure is particularly preferable.
Examples of the radical polymerizable compound having a monofunctional charge transporting structure include hole transporting structures such as triarylamine, hydrazone, pyrazoline, and carbazole, such as condensed polycyclic quinone, diphenoquinone, cyano group, and nitro group. A compound having an electron transport structure such as an electron-withdrawing aromatic ring having a single radical polymerizable functional group. Examples of the radical polymerizable functional group include functional groups represented by the above <Formula 1> or <Formula 2>.
More specifically, those shown for the radically polymerizable compound are mentioned, and acryloyloxy group and methacryloyloxy group are particularly useful. Further, as the charge transporting structure, a triarylamine structure is preferable, and among these, when a compound represented by the structure represented by the following general formula (1) or the following general formula (2) is used, sensitivity, residual Electrical characteristics such as electric potential are well maintained.

In the general formulas (1) and (2), R ₁ has a hydrogen atom, a halogen atom, an alkyl group that may have a substituent, an aralkyl group that may have a substituent, or a substituent. Aryl group, cyano group, nitro group, alkoxy group, —COOR ₇ (wherein R ₇ 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), a carbonyl halide group, CONR ₈ R ₉ (wherein R ₈ and R ₉ may be the same as or different from each other, a hydrogen atom, A halogen 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.
In the general formula (1) and the general formula (2), Ar ₁ and Ar ₂ may be the same as or different from each other, and represent a substituted or unsubstituted arylene group.
In General Formula (1) and General Formula (2), Ar ₃ and Ar ₄ may be the same as or different from each other, and represent a substituted or unsubstituted aryl group.
In the general formula (1) and the general formula (2), X has a single bond, an alkylene group which may have a substituent, a cycloalkylene group which may have a substituent, or a substituent. An alkylene ether group, an oxygen atom, a sulfur atom, or a vinylene group that may be present.
In the general formulas (1) and (2), Z represents an alkylene group which may have a substituent, an alkylene ether divalent group which may have a substituent, or an alkyleneoxycarbonyl divalent group. Represents.
m and n each represent an integer of 0 to 3.

In the general formulas (1) and (2), examples of the alkyl group in the substituent of 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. Examples of the aralkyl group include a benzyl group, a phenethyl group, and a naphthylmethyl group. Examples of the alkoxy group include a methoxy group, an ethoxy group, and a propoxy group. These include halogen atoms, nitro groups, cyano groups; alkyl groups such as methyl groups and ethyl groups; alkoxy groups such as methoxy groups and ethoxy groups; aryloxy groups such as phenoxy groups; aryl groups such as phenyl groups and naphthyl groups; It may be substituted with an aralkyl group such as a benzyl group or a phenethyl group.
Of the substituents for R ₁ , a hydrogen atom or a methyl group is particularly preferable.

Substituted or unsubstituted Ar ₃ and Ar ₄ are aryl groups, and examples of the aryl group include condensed polycyclic hydrocarbon groups, non-fused cyclic hydrocarbon groups, and heterocyclic 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-condensed 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, A monovalent group of a non-condensed polycyclic hydrocarbon compound such as diphenylalkyne, triphenylmethane, distyrylbenzene, 1,1-diphenylcycloalkane, polyphenylalkane, polyphenylalkene, or 9,9-diphenylfluorene The monovalent group of a ring assembly hydrocarbon compound is mentioned.
Examples of the heterocyclic group include monovalent groups such as carbazole, dibenzofuran, dibenzothiophene, oxadiazole, and thiadiazole.

In the general formulas (1) and (2), the aryl group represented by Ar ₃ and Ar ₄ may have a substituent as shown below, for example.
(1) A halogen atom, a cyano group, a nitro group, etc. are mentioned. (2) A linear or branched alkyl group having 1 to 12 carbon atoms, preferably 1 to 8 carbon atoms, more preferably 1 to 4 carbon atoms. Yes, these alkyl groups further include a fluorine atom, a hydroxyl group, a cyano group, an alkoxy group having 1 to 4 carbon atoms, a phenyl group, a halogen atom, an alkyl group having 1 to 4 carbon atoms, or an alkoxy group having 1 to 4 carbon atoms. It may have a phenyl group substituted with. 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 (—OR ₂ ), and R ₂ represents the alkyl group defined in (2) above. 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. These may contain a C1-C4 alkoxy group, a C1-C4 alkyl group, or a halogen atom 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, for example, methylthio group, ethylthio group, phenylthio group, p-methylphenylthio group and the like.

(6) A group represented by the following general formula.
However, in the above formula, R ₃ and R ₄ each independently represent a hydrogen atom, an alkyl group as defined above (2) or aryl group. As an aryl group, a phenyl group, a biphenyl group, or a naphthyl group is mentioned, for example, These may contain a C1-C4 alkoxy group, a C1-C4 alkyl group, or a halogen atom as a substituent. . R ₃ and R ₄ may form a ring together.
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 , A pyrrolidino group, and the like.

(7) An alkylenedioxy group such as a methylenedioxy group or a methylenedithio group, or an alkylenedithio group.
(8) A styryl group that may have a substituent, a β-phenylstyryl group that may have a substituent, 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 .

In the general formulas (1) and (2), X has a single bond, an alkylene group which may have a substituent, a cycloalkylene group which may have a substituent, or a substituent. Represents an alkylene ether group, an oxygen atom, a sulfur atom, or a vinylene group.
The alkylene group which may have a substituent is a linear or branched alkylene group having 1 to 12 carbon atoms, preferably 1 to 8 carbon atoms, more preferably 1 to 4 carbon atoms. The alkylene group is further substituted with a fluorine atom, a hydroxyl group, a cyano group, an alkoxy group having 1 to 4 carbon atoms, a phenyl group or a halogen atom, an alkyl group having 1 to 4 carbon atoms, or an alkoxy group having 1 to 4 carbon atoms. It may have a phenyl group. 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-ethoxy. Examples include ethylene 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 which may have a substituent is a cyclic alkylene group having 5 to 7 carbon atoms. These cyclic alkylene groups include a fluorine atom, a hydroxyl group, an alkyl group having 1 to 4 carbon atoms, and a carbon number. You may have 1-4 alkoxy groups. Specific examples include a cyclohexylidene group, a cyclohexylene group, and a 3,3-dimethylcyclohexylidene group.
Examples of the alkylene ether group which may have a substituent include ethyleneoxy, propyleneoxy, ethylene glycol, propylene glycol, diethylene glycol, tetraethylene glycol, and tripropylene glycol. These alkylene ether group alkylene groups may have a substituent such as a hydroxyl group, a methyl group, or an ethyl group.

Examples of the vinylene group include those represented by the following general formula.
In the general formula, R ₅ represents a hydrogen atom, an alkyl group (said (2) the same as the alkyl group, as defined), or an aryl group (same as the aryl group represented by Ar ₃ and Ar ₄₎ Represents. a represents 1 or 2; b represents 1-3.

In the general formulas (1) and (2), Z is a substituted or unsubstituted alkylene group, an alkylene ether divalent group which may have a substituent, or an alkylene which may have a substituent. Represents an oxycarbonyl divalent group.
Examples of the substituted or unsubstituted alkylene group include the same alkylene groups as those described above for X.
Examples of the alkylene ether divalent group that may have a substituent include the divalent group of the alkylene ether group of X.
Examples of the alkyleneoxycarbonyl divalent group which may have a substituent include caprolactone-modified divalent groups.

Preferred examples of the radical polymerizable compound having a monofunctional charge transport structure further include compounds represented by the following general formula (3).
However, in the said General formula (3), o, p, and q represent the integer of 0 or 1, respectively. Ra represents a hydrogen atom or a methyl group. Rb and Rc represent a substituent other than a hydrogen atom, for example, an alkyl group having 1 to 6 carbon atoms, and may be different in a plurality of cases. s and t each represent an integer of 0 to 3. Za represents a single bond, a methylene group, an ethylene group, or a group represented by the following formula.
In the general formula (3), a compound in which Rb and Rc are a methyl group or an ethyl group is particularly preferable.

  The radically polymerizable compound having a monofunctional charge transport structure represented by the general formulas (1), (2), and (3) is polymerized by opening a carbon-carbon double bond on both sides. Therefore, in a polymer that does not become a terminal structure, is incorporated in a chain polymer, and is crosslinked by polymerization with a radically polymerizable compound having three or more functional groups, it exists in the main chain of the polymer, and Present in the cross-linked chain between the chain and the main chain (this cross-linked chain has an intermolecular cross-linked chain between one polymer and another polymer, and a site where the main chain is folded in one polymer. And other intramolecular cross-linked chains that are cross-linked with other sites derived from the polymerized monomer at positions away from this in the main chain), but even if they are present in the main chain, Even if present, the triarylamine structure suspended from the chain moiety radiates from the nitrogen atom. 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 adopted.

  Specific examples of the radical polymerizable compound having the monofunctional charge transporting structure are shown below, but are not limited to the compounds having these structures.

-Specific examples of radical polymerizable compounds having a functional charge transporting structure-
Specific examples of the radical polymerizable compound having the bifunctional charge transporting structure are shown below, but are not limited to the compounds having these structures.

-3 Specific examples of radical polymerizable compounds having a functional charge transport structure
Specific examples of the radical polymerizable compound having the trifunctional charge transporting structure are shown below, but are not limited to compounds having these structures.

<Synthesis example of compound having monofunctional charge transport structure>
The compound having the monofunctional charge transporting structure can be synthesized, for example, by the method described in Japanese Patent No. 3164426.
(1) Synthesis of hydroxy group-substituted triarylamine compound represented by the following structural formula B 113.85 g (0.3 mol) of a methoxy group-substituted triarylamine compound represented by the following structural formula A and 138 g of sodium iodide ( 0.92 mol) was added 240 ml of sulfolane and heated to 60 ° C. in a nitrogen stream. In this liquid, 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 (silica gel as the adsorption medium and toluene: ethyl acetate = 20: 1 as the developing solvent). Cyclohexane was added to the obtained pale yellow oil to precipitate crystals.
Thus, 88.1 g (yield = 80.4%) of white crystals represented by the following structural formula B was obtained. The melting point of the obtained compound was 64.0-66.0 ° C.

(2) Triarylamino group-substituted acrylate compound (the above exemplified compound No. 54)
82.9 g (0.227 mol) of the hydroxy group-substituted triarylamine compound represented by the above structural formula B obtained in (1) is dissolved in 400 ml of tetrahydrofuran, and an aqueous sodium hydroxide solution (NaOH: 12.2. 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. Thereafter, the reaction was terminated by stirring at 5 ° C. for 3 hours. 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 Nos. Represented by the following structural formulas As a result, 80.73 g (yield = 84.8%) of 54 white crystals were obtained. The melting point of the obtained compound was 117.5 to 119.0 ° C.

  The radical polymerizable compound having the charge transport structure is important for imparting charge transport performance to the surface layer, and the content of the radical polymerizable compound having the charge transport structure is based on the total amount of the surface layer. 20-80 mass% is preferable and 30-70 mass% is more preferable. When the content is less than 20% by mass, the charge transport performance of the surface layer cannot be sufficiently maintained, and deterioration of electrical characteristics such as a decrease in sensitivity and an increase in residual potential may occur in repeated use. If it exceeds the upper limit, the content of the trifunctional or higher functional radical polymerizable compound having no charge transport structure is lowered, resulting in lowering of the crosslink density, and high wear resistance may not be exhibited.

  The surface layer contains a cured product of at least a trifunctional or higher-functional radical polymerizable compound having no charge transporting structure and a radical polymerizable compound having a charge transporting structure. For the purpose of imparting functions such as viscosity adjustment at the time, stress relaxation of the surface layer, low surface energy and friction coefficient reduction, the above-mentioned monofunctional radically polymerizable monomer, bifunctional radically polymerizable monomer, functional monomer, Or a radically polymerizable oligomer can be used together. These radically polymerizable monomers and radically polymerizable oligomers are not particularly limited and can be appropriately selected from known ones according to the purpose.

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

  Examples of the bifunctional radically polymerizable monomer include 1,3-butanediol diacrylate, 1,4-butanediol diacrylate, 1,4-butanediol dimethacrylate, 1,6-hexanediol diacrylate, 1 , 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 fluorine atoms such as octafluoropentyl acrylate, 2-perfluorooctylethyl acrylate, 2-perfluorooctylethyl methacrylate, 2-perfluoroisononylethyl acrylate; Siloxane repeating units described in JP-A-60503 and JP-B-6-45770; 20-70 acryloyl polydimethylsiloxane ethyl, methacryloyl polydimethylsiloxane ethyl, acryloyl polydimethylsiloxane propyl, acryloyl polydimethylsiloxane butyl, diacryloyl polydimethyl Examples thereof include vinyl monomers having a polysiloxane group such as siloxane diethyl, acrylates and methacrylates.

  Examples of the radical polymerizable oligomers include epoxy acrylate oligomers, urethane acrylate oligomers, and polyester acrylate oligomers.

  In addition, when a large amount of monofunctional and bifunctional radically polymerizable monomers and radically polymerizable oligomers are contained, the three-dimensional cross-linking density of the surface layer is substantially lowered, and wear resistance may be lowered. Therefore, the content of these monomers and oligomers is preferably 50 parts by mass or less and more preferably 30 parts by mass or less with respect to 100 parts by mass of the trifunctional or higher functional radical polymerizable compound not having the charge transporting structure.

The surface layer further contains a photopolymerization initiator for efficiently proceeding with a crosslinking reaction between a tri- or higher functional radical polymerizable compound having no charge transport structure and a radical polymerizable compound having a charge transport structure. can do.
The photopolymerization initiator is not particularly limited and may be appropriately selected depending on the intended purpose. Agents, thioxanthone photopolymerization initiators, and other photopolymerization initiators. These may be used individually by 1 type and may use 2 or more types together.

Examples of the acetophenone-based or ketal-based 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-phenyl Examples include propan-1-one, 2-methyl-2-morpholino (4-methylthiophenyl) propan-1-one, and 1-phenyl-1,2-propanedione-2- (o-ethoxycarbonyl) oxime.
Examples of the benzoin ether photopolymerization initiator include benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isobutyl ether, and benzoin isopropyl ether.
Examples of the thioxanthone photopolymerization initiator include benzophenone, 4-hydroxybenzophenone, methyl o-benzoylbenzoate, 2-benzoylnaphthalene, 4-benzoylbiphenyl, 4-benzoylphenyl ether, acrylated benzophenone, 1,4-benzoyl. Examples include benzene.
Examples of the other photopolymerization initiator include ethyl anthraquinone, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, 2,4,6-trimethylbenzoylphenylethoxyphosphine oxide, and bis (2,4,6-trimethylbenzoyl). Phenylphosphine oxide, bis (2,4-dimethoxybenzoyl) -2,4,4-trimethylpentylphosphine oxide, methylphenylglyoxyester, 9,10-phenanthrene, acridine compounds, triazine compounds, imidazole compounds, etc. Can be mentioned.
In addition, what has a photopolymerization acceleration effect can also be used individually or in combination with the said photoinitiator. Examples thereof include triethanolamine, methyldiethanolamine, ethyl 4-dimethylaminobenzoate, isoamyl 4-dimethylaminobenzoate, (2-dimethylamino) ethyl benzoate, 4,4′-dimethylaminobenzophenone, and the like.

  The content of the photopolymerization initiator is preferably 0.5 to 40 parts by mass and more preferably 1 to 20 parts by mass with respect to 100 parts by mass of the total amount of compounds having radical polymerizability.

The surface layer may further 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, if necessary. Known additives can be used as these additives, and those used in general resins such as dibutyl phthalate and dioctyl phthalate can be used as the plasticizer. The amount of the plasticizer used is preferably 20% by mass or less, more preferably 10% by mass or less, based on the total solid content of the surface layer coating solution.
Examples of the leveling agent include silicone oils such as dimethyl silicone oil and methylphenyl silicone oil; polymers or oligomers having a perfluoroalkyl group in the side chain. The amount of the leveling agent used is preferably 3% by mass or less based on the total solid content of the surface layer coating solution.

The surface layer is formed by applying and curing a surface layer coating solution containing at least a trifunctional or higher-functional radical polymerizable compound having no charge transport structure and a radical polymerizable compound having a monofunctional charge transport structure. The When the radically polymerizable compound is a liquid, the surface layer coating liquid can be applied by dissolving other components in the liquid, but if necessary, it is diluted with a solvent and applied.
The solvent is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include alcohols such as methanol, ethanol, propanol and butanol; ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone; acetic acid Esters such as ethyl and butyl acetate; Ethers such as tetrahydrofuran, dioxane and propyl ether; Halogens such as dichloromethane, dichloroethane, trichloroethane and chlorobenzene; Aromatics such as benzene, toluene and xylene; Methyl cellosolve, ethyl cellosolve and cellosolve Examples include cellosolve such as acetate. These may be used individually by 1 type and may use 2 or more types together.

As a method for forming the surface layer, for example, a dipping method, a spray coating method, a ring coating method, a roll coater method, a gravure coating method, a nozzle coating method, a screen printing method and the like are employed. Among these, the spray coating method and the ring coating method are particularly suitable because they are easy to ensure quality stability in production.
There is no restriction | limiting in particular in the thickness of the said surface layer, According to the objective, it can select suitably, 1-10 micrometers is preferable and 2-5 micrometers is more preferable.

<Multi-layer type photosensitive layer>
The multilayer photosensitive layer has at least a charge generation layer and a charge transport layer in this order, and further includes an intermediate layer and other layers as necessary.

-Charge generation layer-
The charge generation layer includes at least a charge generation material, and includes a binder resin and, if necessary, other components.
As the charge generating substance, inorganic materials and organic materials can be used.
Examples of the inorganic material include crystalline selenium, amorphous-selenium, selenium-tellurium, selenium-tellurium-halogen, selenium-arsenic compound, and amorphous-silicon. In amorphous-silicon, dangling bonds terminated with hydrogen atoms and halogen atoms, those doped with boron atoms, phosphorus atoms and the like are suitable.
The organic material is not particularly limited and can be appropriately selected from known materials according to the purpose. Examples thereof include phthalocyanine pigments such as metal phthalocyanine and metal-free phthalocyanine, azulenium salt pigments, methine squaric acid. Pigment, azo pigment having carbazole skeleton, azo pigment having triphenylamine skeleton, azo pigment having diphenylamine skeleton, azo pigment having dibenzothiophene skeleton, azo pigment having fluorenone skeleton, azo pigment having oxadiazole skeleton, bis Azo pigments having a stilbene skeleton, azo pigments having a distyryl oxadiazole skeleton, azo pigments having a distyryl carbazole skeleton, perylene pigments, anthraquinone or polycyclic quinone pigments, quinoneimine pigments, diphenylmethane and triphenyl Enirumetan pigments, benzoquinone pigments, naphthoquinone pigments, cyanine pigments, azomethine pigments, indigoid pigments, and bisbenzimidazole pigments. These may be used individually by 1 type and may use 2 or more types together. Among these, phthalocyanines are preferable, and titanyl phthalocyanine is particularly preferable.
The titanyl phthalocyanine has at least 9.6 ° ± 0.2 °, 24.0 ° ± 0.2 °, and 27.2 ° ± major peaks with a Bragg angle 2θ in an X-ray diffraction spectrum of at least Cu—Kα rays. Those having a crystal type of 0.2 ° are particularly preferable as high-sensitivity materials.

There is no restriction | limiting in particular as said binder resin, According to the objective, it can select suitably, For example, a polyamide resin, a polyurethane resin, an epoxy resin, a polyketone resin, a polycarbonate resin, a silicone resin, an acrylic resin, a polyvinyl butyral resin, polyvinyl Formal resin, polyvinyl ketone resin, polystyrene resin, poly-N-vinyl carbazole resin, polyacrylamide resin, and the like can be given. These may be used individually by 1 type and may use 2 or more types together.
In addition to the binder resin described above, the charge generation layer binder resin may be a polymer charge transport material having a charge transport function, such as (1) an arylamine skeleton, a benzidine skeleton, a hydrazone skeleton, a carbazole skeleton, or a stilbene skeleton. Or a polymer material such as a polycarbonate resin having a pyrazoline skeleton, a polyester resin, a polyurethane resin, a polyether resin, a polysiloxane resin, or an acrylic resin, or (2) a polymer material having a polysilane skeleton.

  Specific examples of the above (1) include JP-A-01-001728, JP-A-01-009964, JP-A-01-013061, JP-A-01-019049, JP-A-01-241559. JP, 04-011627, JP 04-175337, JP 04-183719, JP 04-22514, JP 04-230767, JP 04-320420, JP 05-232727, JP 05-310904, JP 06-234836, JP 06-234837, JP 06-234838, JP 06-234839, JP JP 06-234840, JP 06-234841 A, JP 06-239049 A JP-A 06-236050, JP-A 06-236051, JP-A 06-295077, JP-A 07-056374, JP-A 08-176293, JP 08-208820, JP 08-21640 A, JP 08-253568 A, JP 08-269183 A, JP 09-062019 A, JP 09-038883 A, JP 09-71642 A, JP JP 09-87376, JP 09-104746, JP 09-110974, JP 09-110976, JP 09-157378, JP 09-221544, JP 09-09. No. 227669, JP 09-235367 A, JP 09-241369 JP-A 09-268226, JP-A 09-272735, JP-A 09-302084, JP-A 09-302085, JP-A 09-328539, and the like. Materials.

  Specific examples of the above (2) include, for example, those described in JP-A-63-285552, JP-A-05-19497, JP-A-05-70595, JP-A-10-73944, and the like. Examples are polysilylene polymers.

The charge generation layer may contain a low molecular charge transport material.
The low molecular charge transport material includes a hole transport material and an electron transport material.
Examples of the electron transporting material include chloroanil, bromoanil, 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 -Trinitrodibenzothiophene-5,5-dioxide, diphenoquinone derivatives and the like. These may be used individually by 1 type and may use 2 or more types together.

  Examples of the hole transport material include oxazole derivatives, oxadiazole derivatives, imidazole derivatives, monoarylamine derivatives, diarylamine derivatives, triarylamine derivatives, stilbene derivatives, α-phenylstilbene derivatives, benzidine derivatives, diarylmethane derivatives. , Triarylmethane derivatives, 9-styrylanthracene derivatives, pyrazoline derivatives, divinylbenzene derivatives, hydrazone derivatives, indene derivatives, butadiene derivatives, pyrene derivatives, and the like, and other known materials. These may be used individually by 1 type and may use 2 or more types together.

Methods for forming the charge generation layer can be broadly classified into a vacuum thin film preparation method and a casting method from a solution dispersion system.
As the vacuum thin film production method, for example, 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.
As the casting method, the inorganic or organic charge generating material, if necessary, binder resin, tetrahydrofuran, dioxane, dioxolane, toluene, dichloromethane, monochlorobenzene, dichloroethane, cyclohexanone, cyclopentanone, anisole, xylene, methyl ethyl ketone It can be formed by dispersing with a ball mill, attritor, sand mill, bead mill or the like using a solvent such as acetone, ethyl acetate, butyl acetate, etc., and applying the solution after diluting the dispersion appropriately. Further, a leveling agent such as dimethyl silicone oil or methyl phenyl silicone oil can be added as necessary. The application can be performed by dip coating, spray coating, bead coating, ring coating, or the like.

  The thickness of the charge generation layer is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably 0.01 to 5 μm, and more preferably 0.05 to 2 μm.

-Charge transport layer-
The charge transport layer is a layer intended to hold a charged charge and to couple the charge generated and separated in the charge generation layer by exposure to the charged charge held by movement. In order to achieve the purpose of holding the charged charge, it is required that the electric resistance is high. Further, in order to achieve the purpose of obtaining a high surface potential with the charged charge held, it is required that the dielectric constant is small and the charge mobility is good.

  The charge transport layer includes at least a charge transport material, and includes a binder resin and, if necessary, other components.

Examples of the charge transport material include a hole transport material, an electron transport material, and a polymer charge transport material.
Examples of the electron transporting material (electron accepting material) include chloranil, 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] thiophene-4-one, 1,3,7-trinitrodibenzothiophene-5,5-dioxide, and the like. These may be used individually by 1 type and may use 2 or more types together.

  Examples of the hole transporting material (electron donating material) include oxazole derivatives, oxadiazole derivatives, imidazole derivatives, triphenylamine derivatives, 9- (p-diethylaminostyrylanthracene), 1,1-bis- (4- Dibenzylaminophenyl) propane, styrylanthracene, styrylpyrazoline, phenylhydrazones, α-phenylstilbene derivatives, thiazole derivatives, triazole derivatives, phenazine derivatives, acridine derivatives, benzofuran derivatives, benzimidazole derivatives, thiophene derivatives, etc. . These may be used individually by 1 type and may use 2 or more types together.

Examples of the polymer charge transport material include those having the following structure.
Examples of (a) a polymer having a carbazole ring include, for example, poly-N-vinylcarbazole, JP-A-50-82056, JP-A-54-9632, JP-A-54-11737, JP-A-5-11737. Examples thereof include compounds described in JP-A-4-175337, JP-A-4-183719, and JP-A-6-234841.
(B) Examples of the polymer having a hydrazone structure include, for example, JP-A-57-78402, JP-A-61-20953, JP-A-61-296358, JP-A-1-134456, Compounds described in Kaihei 1-179164, JP-A-3-180851, JP-A-3-180852, JP-A-3-50555, JP-A-5-310904, and JP-A-6-234840 Etc. are exemplified.
(C) Examples of the polysilylene polymer include, for example, JP-A-63-285552, JP-A-1-88461, JP-A-4-264130, JP-A-4-264131, and JP-A-4-264132. Examples thereof include compounds described in JP-A-4-264133 and JP-A-4-289867.
(D) As a polymer having a triarylamine structure, for example, N, N-bis (4-methylphenyl) -4-aminopolystyrene, JP-A-1-134457, JP-A-2-282264, Examples thereof include compounds described in Kaihei 2-304456, JP-A-4-133605, JP-A-4-133066, JP-A-5-40350, and JP-A-5-202135.
(E) As other polymers, for example, a formaldehyde condensation polymer of nitropyrene, JP-A-51-73888, JP-A-56-15049, JP-A-6-234363, JP-A-6-234837 And the compounds described in Japanese Patent Publication No.

  In addition to the above, the polymer charge transporting material includes, for example, a polycarbonate resin having a triarylamine structure, a polyurethane resin having a triarylamine structure, a polyester resin having a triarylamine structure, and a triarylamine structure. And a polyether resin. Examples of the polymer charge transporting material include JP-A 64-1728, JP-A 64-13061, JP-A 64-19049, JP-A-4-11627, JP-A 4-116627. 2225014, JP-A-4-230767, JP-A-4-320420, JP-A-5-232727, JP-A-7-56374, JP-A-9-127713, JP-A-9-222740. And compounds described in JP-A-9-265197, JP-A-9-211877, JP-A-9-30495, and the like.

  Examples of the polymer having an electron donating group include not only the above-mentioned polymer but also a copolymer with a known monomer, a block polymer, a graft polymer, a star polymer, It is also possible to use a crosslinked polymer having an electron donating group as disclosed in JP-A-109406.

Examples of the binder resin include polycarbonate resin, polyester resin, methacrylic resin, acrylic resin, polyethylene resin, polyvinyl chloride resin, polyvinyl acetate resin, polystyrene resin, phenol resin, epoxy resin, polyurethane resin, polyvinylidene chloride resin, Examples include alkyd resins, silicone resins, polyvinyl carbazole resins, polyvinyl butyral resins, polyvinyl formal resins, polyacrylate resins, polyacrylamide resins, and phenoxy resins. These may be used individually by 1 type and may use 2 or more types together.
The charge transport layer may also contain a copolymer of a crosslinkable binder resin and a crosslinkable charge transport material.

The charge transport layer can be formed by dissolving or dispersing these charge transport materials and a binder resin in an appropriate solvent, applying the solution, and drying. In addition to the charge transport material and the binder resin, an appropriate amount of additives such as a plasticizer, an antioxidant, and a leveling agent can be added to the charge transport layer as necessary.
Examples of the plasticizer include dibutyl phthalate and dioctyl phthalate, and the amount used is preferably about 0 to 30 parts by mass with respect to 100 parts by mass of the binder resin.
Examples of the leveling agent include silicone oils such as dimethyl silicone oil and methylphenyl silicone oil; polymers or oligomers having a perfluoroalkyl group in the side chain, and the amount used is 100 parts by mass of the binder resin. About 0 to 1 part by mass is preferable.

As the solvent used for coating the charge transport layer, the same solvent as the charge generation layer can be used, but a solvent that dissolves the charge transport material and the binder resin well is preferable. The charge transport layer can be formed by a coating method similar to that for the charge generation layer.
There is no restriction | limiting in particular in the thickness of the said charge transport layer, According to the objective, it can select suitably, 5-40 micrometers is preferable and 10-30 micrometers is more preferable.

  When the photosensitive layer has a laminated structure, a coating solution containing a radically polymerizable composition is applied on the charge transport layer, dried as necessary, and cured by light energy irradiation to form a surface layer. 1-20 micrometers is preferable and, as for the thickness of the said surface layer, 2-10 micrometers is more preferable. If the thickness is less than 1 μm, unevenness in durability may occur due to uneven thickness, and if it exceeds 20 μm, the electrical characteristics may deteriorate.

<Single layer type photosensitive layer>
The single-layer type photosensitive layer includes a charge generation material, a charge transport material, and a binder resin, and further includes other components as necessary.
As the charge generation material, the charge transport material, and the binder resin, the same material as that of the laminated photosensitive layer can be used. As the charge generation material, titanyl phthalocyanine is preferable as described above.

When a single-layer type photosensitive layer is provided by a casting method, the single-layer type photosensitive layer is prepared by dissolving or dispersing a charge generating substance, a low-molecular-weight and a high-molecular charge-transporting substance in an appropriate solvent, and applying and drying the same. Can be formed. In addition, a plasticizer can be added to the single-layer type photosensitive layer as necessary. Furthermore, as the binder resin that can be used as necessary, the binder resins mentioned in the charge transport layer can be used as they are. In addition, you may mix and use the binder resin similar to a charge generation layer.
Moreover, a plasticizer, a leveling agent, etc. can also be added as needed. As the method for dispersing the charge generation material, the same charge generation material, charge transport material, plasticizer, and leveling agent as those already described in the charge generation layer and charge transport layer can be used. As the binder resin, in addition to the binder resin mentioned in the section of the charge transport layer, the binder resin mentioned in the charge generation layer may be mixed and used. The polymer charge transport material can also be used.

There is no restriction | limiting in particular in the thickness of the said single layer type photosensitive layer, According to the objective, it can select suitably, 5-30 micrometers is preferable and 10-25 micrometers is more preferable.
In the case of the single-layer type photosensitive layer, a coating solution containing a radically polymerizable composition is applied on the photosensitive layer, further dried as necessary, and then cured by light energy irradiation means to form a surface layer. . At this time, the thickness of the surface layer is preferably 1 to 20 μm, and more preferably 2 to 10 μm. If the thickness is less than 1 μm, unevenness in durability may occur due to thickness unevenness, and if it exceeds 20 μm, the electrical characteristics may deteriorate.
The charge generation material contained in the single-layer type photosensitive layer is preferably 1 to 30% by mass with respect to the total amount of the photosensitive layer. The binder resin contained in the lower layer portion of the photosensitive layer is preferably 20 to 80% by mass with respect to the total amount of the photosensitive layer. Further, the content of the charge transport material is preferably 10 to 70 parts by mass with respect to 100 parts by mass of the binder resin.

<Support>
There is no restriction | limiting in particular as said support body, Although it can select suitably according to the objective, The thing which shows the electroconductivity whose volume resistance is 10 < ¹⁰ > ohm * cm or less is suitable.
As the support, there is no particular limitation on the material, shape, and size, and any of a plate shape, a drum shape, or a belt shape can be used. For example, aluminum, nickel, chromium, nichrome, copper, gold, Metals such as silver and platinum; Metal oxides such as tin oxide and indium oxide coated on film or cylindrical plastic or paper by vapor deposition or sputtering; or plates such as aluminum, aluminum alloy, nickel, and stainless steel, or After extruding them and making them into pipes by a method such as drawing, it is possible to use pipes that have been subjected to surface treatment such as cutting, superfinishing, or polishing. Further, an endless nickel belt and an endless stainless steel belt disclosed in JP-A-52-36016 can also be used as a support.

In addition to the above, it is also possible to use a conductive layer formed by dispersing conductive powder on an appropriate binder resin and coating the support.
Examples of the material of the conductive powder include carbon black and 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. Etc. Examples of the binder resin include polystyrene resin, styrene-acrylonitrile copolymer, styrene-butadiene copolymer, styrene-maleic anhydride copolymer, polyester resin, polyvinyl chloride resin, vinyl chloride-vinyl acetate copolymer. Copolymer, polyvinyl acetate resin, polyvinylidene chloride resin, polyarylate resin, phenoxy resin, polycarbonate resin, cellulose acetate resin, ethyl cellulose resin, polyvinyl butyral resin, polyvinyl formal resin, polyvinyl toluene resin, poly-N-vinyl carbazole resin, acrylic Examples thereof include resins, silicone resins, epoxy resins, melamine resins, urethane resins, phenol resins, alkyd resins, and the like.
The conductive layer can be formed by applying a coating solution obtained by dissolving or dispersing the conductive powder and a binder resin in a solvent on a support. Examples of the solvent include tetrahydrofuran, dichloromethane, methyl ethyl ketone, toluene, and the like.

  In addition, the conductive powder is contained in the cylindrical substrate in polyvinyl chloride resin, polypropylene resin, polyester resin, polystyrene resin, polyvinylidene chloride resin, polyethylene resin, chlorinated rubber, polytetrafluoroethylene fluororesin, or the like. It is also preferable to provide a conductive layer with a heat shrinkable tube.

  An undercoat layer may be provided between the support and the photosensitive layer as necessary. The undercoat layer contains a resin as a main component. However, considering that the photosensitive layer on the undercoat layer is coated with a solvent, the resin is preferably a resin having high solvent resistance. Examples of the resin include water-soluble resins such as polyvinyl alcohol, casein, and sodium polyacrylate; alcohol-soluble resins such as copolymer nylon and methoxymethylated nylon; polyurethane resins, melamine resins, phenol resins, alkyd-melamine resins, Examples thereof include a curable resin that forms a three-dimensional network structure such as an epoxy resin.

In addition, a metal oxide such as titanium oxide, silica, alumina, zirconium oxide, tin oxide, or indium oxide may be added to the undercoat layer in order to prevent moire and reduce residual potential.
The undercoat layer can be formed by a solvent coating method in the same manner as the photosensitive layer. Furthermore, a silane coupling agent, a titanium coupling agent, a chromium coupling agent, or the like can be used for the undercoat layer. In the undercoat layer, Al ₂ O ₃ is provided by anodic oxidation; an organic material such as polyparaxylylene (parylene); an inorganic material such as SiO ₂ , SnO ₂ , TiO ₂ , ITO, or CeO ₂ is formed into a vacuum thin film. Those provided by the law can also be suitably used.
There is no restriction | limiting in particular in the thickness of the said undercoat layer, Although it can select suitably according to the objective, 0-5 micrometers is preferable.

In the electrophotographic photosensitive member of the present invention, in order to improve environmental resistance, the surface layer, the photosensitive layer, the charge generation layer, the charge transport layer, the undercoat layer, in particular, for the purpose of preventing a decrease in sensitivity and an increase in residual potential. An antioxidant can be added to each layer.
There is no restriction | limiting in particular as said antioxidant, Although it can select suitably according to the objective, For example, a phenol type compound, paraphenylenediamine, organic sulfur compounds, organic phosphorus compounds, etc. are mentioned.
Examples of the phenol compound include 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-t-butylphenol), 2,2'-methylene-bis- (4-ethyl- 6-t-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-hydroxy Ben ) Benzene, tetrakis- [methylene-3- (3 ′, 5′-di-t-butyl-4′-hydroxyphenyl) propionate] methane, bis [3,3′-bis (4′-hydroxy-3 ′) -T-butylphenyl) butyric acid] glycol ester, tocopherols and the like.
Examples of the paraphenylenediamines include N-phenyl-N′-isopropyl-p-phenylenediamine, N, N′-di-sec-butyl-p-phenylenediamine, N-phenyl-N-sec-butyl- Examples include p-phenylenediamine, N, N′-di-isopropyl-p-phenylenediamine, N, N′-dimethyl-N, N′-di-t-butyl-p-phenylenediamine, and the like.
Examples of the hydroquinones include 2,5-di-t-octyl hydroquinone, 2,6-didodecyl hydroquinone, 2-dodecyl hydroquinone, 2-dodecyl-5-chlorohydroquinone, 2-t-octyl-5-methyl. Examples include hydroquinone and 2- (2-octadecenyl) -5-methylhydroquinone.
Examples of the organic sulfur compounds include dilauryl-3,3′-thiodipropionate, distearyl-3,3′-thiodipropionate, ditetradecyl-3,3′-thiodipropionate, and the like. .
Examples of the organic phosphorus compounds include 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, oils and fats, and commercially available products can be easily obtained.
The addition amount of the antioxidant is preferably 0.01 to 10% by mass with respect to the total mass of the layer to be added.

(Method for producing electrophotographic photoreceptor)
The method for producing an electrophotographic photoreceptor of the present invention is a method for producing the electrophotographic photoreceptor of the present invention,
Comprising at least a surface layer forming step of forming a surface layer by curing a radically polymerizable compound having three or more functional groups having no charge transporting structure and a radical polymerizable compound having a charge transporting structure by light irradiation; Further, it includes other steps as necessary.
In this case, the initial surface temperature of the electrophotographic photosensitive member at the start of light irradiation is 10 ° C. or more and 25 ° C. or less. Further, the maximum surface temperature of the electrophotographic photosensitive member during light irradiation is 40 ° C. or higher and 140 ° C. or lower.
Further, the adjustment of the surface temperature of the electrophotographic photosensitive member is preferably an embodiment in which the inner surface of the electrophotographic photosensitive member is brought into contact with a cooling means to control the surface temperature of the photosensitive member, and the cooling means is controlled by an external thermostat. It is preferable to introduce a controlled refrigerant into the mandrel tube and circulate it between the thermostat.

As the light irradiation, a UV irradiation light source such as a high pressure mercury lamp or a metal halide lamp mainly having an emission wavelength in ultraviolet light can be used. Is also possible. Others include those that use an electron beam as the radiation energy, but those using light energy are useful because of the ease of reaction rate control and the simplicity of the apparatus.
The irradiation light quantity is preferably 50 mW / cm ² or more, and more preferably 1,000 mW / cm ² or less. If the irradiation amount is less than 50 mW / cm ^2, it may take time for the curing reaction, exceeds 1,000 mW / cm ^2, the progress of the reaction becomes uneven, rough surface layer that becomes severe is there.

  Here, an example of the method for producing the electrophotographic photosensitive member of the present invention will be given. First, the surface layer coating solution prepared above is applied by spray or the like on a photoreceptor in which an undercoat layer, a charge generation layer, and a charge transport layer are sequentially laminated on a support such as an aluminum cylinder, and then irradiated with light. The surface layer is cured by means. After the curing is completed, the electrophotographic photoreceptor of the present invention can be obtained by heating at 100 to 150 ° C. for 10 to 30 minutes to reduce the residual solvent.

  The electrophotographic photosensitive member of the present invention can be widely used not only for electrophotographic copying machines but also for electrophotographic application fields such as laser beam printers, CRT printers, LED printers, liquid crystal printers, laser plate making, and the like. The image forming method, the image forming apparatus, and the process cartridge of the present invention described below are preferably used.

(Image forming method and image forming apparatus)
The image forming apparatus of the present invention comprises at least an electrophotographic photosensitive member, an electrostatic latent image forming unit, a developing unit, a transfer unit, and a fixing unit, and other types appropriately selected as necessary. Means, for example, static elimination means, cleaning means, recycling means, control means and the like.
The image forming method of the present invention includes at least an electrostatic latent image forming step, a developing step, a transfer step, and a fixing step, and other steps appropriately selected as necessary, for example, a static elimination step, a cleaning step. , Including recycling process, control process, etc.

  The image forming method of the present invention can be preferably carried out by the image forming apparatus of the present invention, the electrostatic latent image forming step can be performed by the electrostatic latent image forming means, and the developing step is the developing The transfer step can be performed by the transfer unit, the fixing step can be performed by the fixing unit, and the other steps can be performed by the other unit.

-Electrostatic latent image forming step and electrostatic latent image forming means-
The electrostatic latent image forming step is a step of forming an electrostatic latent image on the electrophotographic photosensitive member.
As the electrophotographic photoreceptor, the electrophotographic photoreceptor of the present invention is used.

  The formation of the electrostatic latent image can be performed, for example, by uniformly charging the surface of the electrophotographic photosensitive member and then performing imagewise exposure, and can be performed by the electrostatic latent image forming unit. it can. The electrostatic latent image forming means includes at least a charger that uniformly charges the surface of the electrophotographic photosensitive member and an exposure device that exposes the surface of the electrophotographic photosensitive member imagewise.

The charging can be performed, for example, by applying a voltage to the surface of the electrophotographic photosensitive member using the charger.
The charger is not particularly limited and may be appropriately selected depending on the purpose. For example, a known contact charging device including a conductive or semiconductive roller, brush, film, rubber blade, etc. And non-contact chargers using corona discharge such as corotrons and corotrons.

The shape of the charging member may take any form such as a magnetic brush or a fur brush in addition to a roller, and can be appropriately selected according to the specifications and form of the electrophotographic apparatus. When the magnetic brush is used, the magnetic brush is composed of, for example, various ferrite particles such as Zn-Cu ferrite as a charging member, and a non-magnetic conductive sleeve for supporting the ferrite member, and a magnet roll included in the non-magnetic conductive sleeve. The Or when using a brush, for example, as a material of the fur brush, a fur treated with carbon, copper sulfide, metal, or metal oxide is used, and this is wound around a metal or other conductive core. Make it a charger by sticking.
The charger is not limited to the contact charger as described above, but a contact charger is particularly preferable because an image forming apparatus in which ozone generated from the charger is reduced can be obtained. .
It is preferable that the charger is disposed in contact or non-contact with the electrophotographic photosensitive member and charges the surface of the electrophotographic photosensitive member by applying a direct current and an alternating voltage.
The charger is a charging roller that is disposed in close proximity to the electrophotographic photosensitive member via a gap tape, and charges the surface of the electrophotographic photosensitive member by applying a direct current and an alternating voltage to the charging roller. Those are preferred.
The exposure can be performed, for example, by exposing the surface of the electrophotographic photosensitive member imagewise using the exposure device.
The exposure device is not particularly limited as long as it can perform imagewise exposure on the surface of the electrophotographic photosensitive member charged by the charger, and can be appropriately selected according to the purpose. However, various exposure devices such as a copying optical system, a rod lens array system, a laser optical system, and a liquid crystal shutter optical system can be used.
In the present invention, an optical backside system that performs imagewise exposure from the backside of the electrophotographic photosensitive member may be employed.

-Development process and development means-
The developing step is a step of developing the electrostatic latent image using the toner or the developer to form a visible image.
The visible image can be formed, for example, by developing the electrostatic latent image using the toner or the developer, and can be performed by the developing unit.
The developing unit is not particularly limited as long as it can be developed using, for example, the toner or the developer, and can be appropriately selected from known ones. For example, the toner or developer is accommodated. Preferred examples include those having at least a developing unit capable of bringing the toner or developer into contact or non-contact with the electrostatic latent image.

  The developing unit may be a dry developing type, a wet developing type, a single color developing unit, or a multi-color developing unit. For example, a toner having a stirrer for charging the toner or the developer by frictional stirring and a rotatable magnet roller is preferable.

  In the developing device, for example, the toner and the carrier are mixed and agitated, and the toner is charged by friction at that time, and held on the surface of the rotating magnet roller in a raised state to form a magnetic brush. . Since the magnet roller is disposed in the vicinity of the electrophotographic photosensitive member, a part of the toner constituting the magnetic brush formed on the surface of the magnet roller is electrically attracted to the electrophotographic photosensitive member. Move to the body surface. As a result, the electrostatic latent image is developed with the toner to form a visible image with the toner on the surface of the electrophotographic photosensitive member.

  The developer accommodated in the developing device may be a one-component developer or a two-component developer.

-Transfer process and transfer means-
The transfer step is a step of transferring the visible image onto a recording medium. The intermediate recording medium is used to primarily transfer the visible image onto the intermediate recording medium, and then the visible image is transferred onto the recording medium. A primary transfer step of forming a composite transfer image by transferring a visible image onto an intermediate recording medium using two or more colors, preferably a full color toner as the toner, and a composite transfer image; A mode including a secondary transfer step of transferring the transfer image onto the recording medium is more preferable.
The transfer can be performed, for example, by charging the visible image with the electrophotographic photosensitive member using a transfer charger, and can be performed by the transfer unit. The transfer unit includes a primary transfer unit that transfers a visible image onto an intermediate recording medium to form a composite transfer image, and a secondary transfer unit that transfers the composite transfer image onto a recording medium. Embodiments are preferred.
The intermediate recording medium is not particularly limited and may be appropriately selected from known recording media according to the purpose. For example, a transfer belt or the like is preferable.

The transfer means (the primary transfer means and the secondary transfer means) includes at least a transfer unit that peels and charges the visible image formed on the electrophotographic photosensitive member toward the recording medium. preferable. There may be one transfer means or two or more transfer means.
Examples of the transfer device include a corona transfer device using corona discharge, a transfer belt, a transfer roller, a pressure transfer roller, and an adhesive transfer device.
The recording medium is typically plain paper, but is not particularly limited as long as it can transfer an unfixed image after development, and can be appropriately selected according to the purpose. PET for OHP A base or the like can also be used.

The fixing step is a step of fixing the visible image transferred to the recording medium using a fixing device, and may be performed each time the toner of each color is transferred to the recording medium, or for the toner of each color. You may perform this simultaneously in the state which laminated | stacked this.
There is no restriction | limiting in particular as said fixing device, Although it can select suitably according to the objective, A well-known heating-pressing means is suitable. Examples of the heating and pressing means include a combination of a heating roller and a pressure roller, a combination of a heating roller, a pressure roller, and an endless belt.
The heating in the heating and pressing means is usually preferably 80 ° C to 200 ° C.
In the present invention, for example, a known optical fixing device may be used together with or in place of the fixing step and the fixing unit depending on the purpose.

The neutralization step is a step of performing neutralization by applying a neutralization bias to the electrophotographic photosensitive member, and can be suitably performed by a neutralization unit.
The neutralization means is not particularly limited, and may be appropriately selected from known neutralizers as long as it can apply a neutralization bias to the electrophotographic photosensitive member. For example, a neutralization lamp is preferably used. Can be mentioned.

The cleaning step is a step of removing the toner remaining on the electrophotographic photosensitive member, and can be suitably performed by a cleaning unit.
The cleaning means is not particularly limited as long as it can remove the electrophotographic toner remaining on the electrophotographic photosensitive member, and can be appropriately selected from known cleaners. For example, a magnetic brush cleaner Suitable examples include electrostatic brush cleaners, magnetic roller cleaners, blade cleaners, brush cleaners, web cleaners, and the like.

The recycling step is a step of recycling the toner removed by the cleaning step to the developing unit, and can be suitably performed by the recycling unit.
There is no restriction | limiting in particular as said recycling means, A well-known conveyance means etc. are mentioned.

The control means is a process for controlling the respective steps, and can be suitably performed by the control means.
The control means is not particularly limited as long as the movement of each means can be controlled, and can be appropriately selected according to the purpose. Examples thereof include devices such as a sequencer and a computer.

  Here, an aspect of carrying out the image forming method of the present invention by the image forming apparatus of the present invention will be described with reference to the drawings. FIG. 7 is a schematic view showing an example of the image forming apparatus of the present invention.

In this image forming apparatus, a charging charger 3 is used as means for uniformly charging the electrophotographic photosensitive member. Examples of charging means other than the charging charger include a corotron device, a scorotron device, a solid discharge element, a needle electrode device, a roller charging device, and a conductive brush device.
The configuration of the image forming apparatus of the present invention is effective when a charging unit such as a contact charging method or a non-contact proximity arrangement charging method in which the photosensitive composition is decomposed by proximity discharge from the charging unit is used. 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. 10-200 micrometers is preferable and the magnitude | size of the said space | gap has more preferable 10-100 micrometers. If the size of the gap is too large, charging may become unstable, and if it is too small, the surface of the charging member may be contaminated when toner remaining on the photoreceptor is present. .

  Next, exposure means 5 is used to form an electrostatic latent image on the uniformly charged electrophotographic photosensitive member 1. As an exposure light source in this exposure means, for example, fluorescent materials such as fluorescent lamps, tungsten lamps, halogen lamps, mercury lamps, sodium lamps, light emitting diodes (LEDs), semiconductor lasers (LD), electroluminescence (EL), etc. Can do. In order to irradiate only light in a desired wavelength range, various 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.

  A 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 or a two-component development method, and a wet development method using a wet toner. When a positive (negative) charge is applied to the photoreceptor and image exposure is performed, a positive (negative) electrostatic latent image is formed on the surface of the electrophotographic photoreceptor. If this is developed with toner of negative (positive) polarity (detection fine particles), a positive image can be obtained, and if developed with toner of positive (negative) polarity, a negative image can be obtained.

Next, a transfer charger 210 is used to transfer a visible image (toner image) visualized on the electrophotographic photosensitive member onto the recording medium 9. Further, a pre-transfer charger 7 may be used in order to perform transfer more efficiently. 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.
A separation charger 211 and a separation claw 212 are used as means for separating the recording medium 9 from the electrophotographic 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 211, the charging means can be used.

A fur brush 214 and a cleaning blade 215 are used to clean residual toner remaining on the photoreceptor after transfer. Further, a pre-cleaning charger 213 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.
A neutralizing means is used for the purpose of removing the latent image on the electrophotographic photosensitive member as necessary. As the charge removal means, a charge removal lamp 2 and a charge removal charger are used, and the exposure light source and charging means can be used, respectively.
In addition, known processes such as document reading, paper feeding, fixing, and paper ejection that are not close to the electrophotographic photosensitive member can be used.

Next, another mode for carrying out the image forming method of the present invention by the image forming apparatus of the present invention will be described with reference to FIG. The tandem image forming apparatus shown in FIG. 8 is a tandem type color image forming apparatus. The tandem color image forming apparatus includes a copying apparatus main body 150, a paper feed table 200, a scanner 300, and an automatic document feeder (ADF) 400.
The copying apparatus main body 150 is provided with an endless belt-like intermediate transfer member 50 at the center. The intermediate transfer member 50 is stretched around the support rollers 14, 15 and 16, and can be rotated clockwise in FIG. 8. An intermediate transfer member cleaning device 17 for removing residual toner on the intermediate transfer member 50 is disposed in the vicinity of the support roller 15. The intermediate transfer member 50 stretched between the support roller 14 and the support roller 15 is a tandem type in which four image forming units 18 of yellow, cyan, magenta, and black are arranged to face each other along the conveyance direction. A developing device 120 is disposed. An exposure device 21 is disposed in the vicinity of the tandem developing device 120. A secondary transfer device 22 is disposed on the side of the intermediate transfer member 50 opposite to the side on which the tandem developing device 120 is disposed. In the secondary transfer device 22, a secondary transfer belt 24, which is an endless belt, is stretched around a pair of rollers 23, and the recording medium conveyed on the secondary transfer belt 24 and the intermediate transfer member 50 are in contact with each other. Is possible. A fixing device 25 is disposed in the vicinity of the secondary transfer device 22. The fixing device 25 includes a fixing belt 26 that is an endless belt, and a pressure roller 27 that is pressed against the fixing belt 26.
Note that a sheet reversing device 28 for reversing the recording medium in order to form an image on both sides of the recording medium is disposed in the vicinity of the secondary transfer device 22 and the fixing device 25.

  Next, formation of a full color image (color copy) using the tandem image forming apparatus will be described. That is, first, a document is set on the document table 130 of the automatic document feeder (ADF) 400, or the automatic document feeder 400 is opened and the document is set on the contact glass 32 of the scanner 300. 400 is closed.

  When a start switch (not shown) is pressed, when the document is set on the automatic document feeder 400, the document is transported and moved onto the contact glass 32, and then the document is set on the contact glass 32. Immediately after that, the scanner 300 is driven, and the first traveling body 33 and the second traveling body 34 travel. At this time, light from the light source is irradiated by the first traveling body 33 and reflected light from the document surface is reflected by the mirror in the second traveling body 34 and is received by the reading sensor 36 through the imaging lens 35 to be color. A document (color image) is read and used as black, yellow, magenta, and cyan image information.

  Each image information of black, yellow, magenta, and cyan is stored in each image forming unit 18 (black image forming unit, yellow image forming unit, magenta image forming unit, and cyan image) in the tandem image forming apparatus. Each of the image forming units forms black, yellow, magenta, and cyan toner images. That is, each image forming means 18 (black image forming means, yellow image forming means, magenta image forming means, and cyan image forming means) in the tandem image forming apparatus, as shown in FIG. A photoconductor 10 (black photoconductor 10K, yellow photoconductor 10Y, magenta photoconductor 10M, and cyan photoconductor 10C), a charging device 160 for uniformly charging the photoconductor, and each color image information An exposure device (not shown) that exposes the photoconductor on each color image-corresponding image (L in FIG. 9) and forms an electrostatic latent image corresponding to each color image on the photoconductor, A developing device 61 that develops the electrostatic latent image with each color toner (black toner, yellow toner, magenta toner, and cyan toner) to form a toner image with each color toner; A transfer charging device 62 for transferring the toner image onto the intermediate transfer member 50, a cleaning device 63, and a charge eliminating device 64 are provided, and each monochrome image (black image) is based on the image information of each color. , Yellow image, magenta image, and cyan image) can be formed. The black image, the yellow image, the magenta image, and the cyan image formed in this way are respectively transferred onto the black photoconductor 10K on the intermediate transfer member 50 that is rotationally moved by the support rollers 14, 15, and 16. The formed black image, the yellow image formed on the yellow photoconductor 10Y, the magenta image formed on the magenta photoconductor 10M, and the cyan image formed on the cyan photoconductor 10C are sequentially transferred ( Primary transfer). Then, the black image, the yellow image, the magenta image, and the cyan image are superimposed on the intermediate transfer member 50 to form a composite color image (color transfer image).

On the other hand, in the paper feed table 200, one of the paper feed rollers 142 is selectively rotated to feed the recording medium from one of the paper feed cassettes 144 provided in multiple stages in the paper bank 143, and one sheet at a time by the separation roller 145. The paper is separated and sent to the paper feed path 146, transported by the transport roller 147, guided to the paper feed path 148 in the copying machine main body 150, and abutted against the registration roller 49 to stop. Alternatively, the recording roller 142 is rotated to feed out the recording medium on the manual feed tray 54, separated one by one by the separation roller 52, put into the manual feed path 53, and abutted against the registration roller 49 and stopped. The registration roller 49 is generally used while being grounded, but may be used in a state where a bias is applied to remove paper dust from the sheet.
Then, the registration roller 49 is rotated in synchronization with the synthesized color image (color transfer image) synthesized on the intermediate transfer member 50, and the recording medium is sent between the intermediate transfer member 50 and the secondary transfer device 22. Then, the composite color image (color transfer image) is transferred (secondary transfer) onto the recording medium by the secondary transfer device 22, whereby a color image is transferred and formed on the recording medium. The residual toner on the intermediate transfer member 50 after image transfer is cleaned by the intermediate transfer member cleaning device 17.

  The recording medium on which the color image has been transferred is conveyed by the secondary transfer device 22 and sent to the fixing device 25, where the combined color image (color transfer image) is generated by heat and pressure. Is fixed on the recording medium. Thereafter, the recording medium is switched by the switching claw 55 and discharged by the discharge roller 56 and stacked on the paper discharge tray 57. Alternatively, the recording medium is switched by the switching claw 55 and reversed by the sheet reversing device 28 to return to the transfer position. After guiding and recording an image on the back side, the image is discharged by the discharge roller 56 and stacked on the discharge tray 57.

(Process cartridge)
The process cartridge of the present invention has the electrophotographic photosensitive member of the present invention and at least one means selected from a charging means, a developing means, a transfer means, a cleaning means, and a charge eliminating means, and, if necessary, other Means and is detachable from the main body of the image forming apparatus.

Here, as shown in FIG. 10, the process cartridge includes an electrophotographic photosensitive member 101, and at least one of a charging unit 102, a developing unit 104, a transfer unit 106, a cleaning unit 107, and a charge eliminating unit (not shown). And is detachable from the main body of the image forming apparatus.
Referring to the image forming process using the process cartridge shown in FIG. 10, the electrophotographic photosensitive member 101 is rotated on the surface by charging by the charging means 102 and exposure 103 by the exposure means (not shown) while rotating in the direction of the arrow in the figure. An electrostatic latent image corresponding to the exposure image is formed. The electrostatic latent image is developed by the developing unit 104, and the obtained visible image is transferred to the recording medium 105 by the transfer unit 106 and printed out. Next, the surface of the electrophotographic photosensitive member after the transfer is cleaned by the cleaning unit 107, and is further neutralized by a neutralizing unit (not shown), and the above operation is repeated again.

  In the image forming apparatus, the image forming method, and the process cartridge of the present invention, an electrophotographic photosensitive member having a smooth and highly durable surface layer, high wear resistance, and good electrical characteristics is used. Therefore, high-definition and high-quality images can be formed over a long period of time.

  Examples of the present invention will be described below, but the present invention is not limited to these examples.

(Synthesis Example 1)
292 g of 1,3-diiminoisoindoline and 2,000 ml of sulfolane were mixed, and 204 g of titanium tetrabutoxide was added dropwise under a nitrogen stream. After completion of the dropping, the temperature was gradually raised to 180 ° C., and the reaction was carried out by stirring for 5 hours while keeping the reaction temperature between 170 ° C. and 180 ° C. After the completion of the reaction, the mixture was allowed to cool and then the precipitate was filtered and washed with chloroform until the powder turned blue. Next, it was washed several times with methanol, washed several times with hot water at 80 ° C. and then dried to obtain crude titanyl phthalocyanine. The obtained crude titanyl phthalocyanine was dissolved in 20 times the amount of concentrated sulfuric acid, dropped into 100 times the amount of ice water with stirring, and the precipitated crystals were filtered. Next, washing with water was repeated until the washing solution became neutral, and a wet cake of titanyl phthalocyanine pigment was obtained. The wet cake was washed with ion exchange water.
20 g of the obtained wet cake was put into 200 g of 1,2-dichloroethane and stirred for 4 hours. After adding 1,000 g of methanol to this and stirring for 1 hour, it filtered and dried and obtained titanyl phthalocyanine powder.
The X-ray diffraction spectrum of the obtained titanyl phthalocyanine pigment was measured under the following conditions.
[X-ray diffraction spectrum conditions]
・ X-ray tube: Cu
・ Voltage: 40kV
・ Current: 20mA
Scanning speed: 1 ° / min Scanning range: 3 ° -40 °
・ Time constant: 2 seconds

  An X-ray diffraction spectrum of the titanyl phthalocyanine pigment obtained in Synthesis Example 1 is shown in FIG. From the results of FIG. 11, the obtained titanyl phthalocyanine pigment has a major peak with a Bragg angle 2θ of at least 9.6 ° ± 0.2 °, 24.0 ° ± 0.2 °, and 27.2 ° ± 0.2. It was found to have a crystal form at °.

Example 1
-Production of electrophotographic photoreceptor-
By sequentially applying an undercoat layer coating solution, a charge generation layer coating solution, and a charge transport layer coating solution having the following composition onto an aluminum cylinder having an outer diameter of 30 mm and a length of 340 mm, and drying. Then, an undercoat layer having a thickness of 3.5 μm, a charge generation layer having a thickness of 0.3 μm, and a charge transport layer having a thickness of 25 μm were formed.

[Composition of coating liquid for undercoat layer]
・ Alkyd resin (Beckosol 1307-60-EL, manufactured by Dainippon Ink & Chemicals, Inc.) ... 6 parts by mass Melamine resin (Super Becamine G-821-60, manufactured by Dainippon Ink & Chemicals, Inc.) -4 parts by mass-Titanium oxide (CREL, manufactured by Ishihara Sangyo Co., Ltd.) ... 40 parts by mass-Methyl ethyl ketone ... 50 parts by mass

[Composition of coating solution for charge generation layer]
-Bisazo pigment represented by the following structural formula: 2.5 parts by mass
・ Polyvinyl butyral (XYHL, manufactured by UCC): 0.5 part by mass ・ Cyclohexanone: 200 part by mass ・ Methyl ethyl ketone: 80 part by mass

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

Next, a coating solution for a crosslinked surface layer having the following composition was spray-coated on the obtained charge transport layer.
[Composition of coating solution for crosslinked surface layer]
・ Trimethylolpropane trimethacrylate (SR-350, manufactured by Nippon Kayaku Co., Ltd.) as a tri- or more functional radical polymerizable monomer having no charge transport structure: 10 parts by mass ・ Represented by the following structural formula Exemplified compound No. 1 as a radical polymerizable compound having a monofunctional charge transporting structure. 54 ... 10 parts by mass
1-hydroxy-cyclohexyl-phenyl-ketone (Irgacure 184, manufactured by Ciba Specialty Chemicals) ... 1 part by mass Tetrahydrofuran ... 100 parts by mass

Next, after 10-minute touch drying, an aluminum cylinder was attached to the mandrel tube. The length of the mandrel tube was 360 mm, the temperature of the water circulated inside the mandrel tube was 12 ° C., the direction of water circulation was from the bottom to the top of the mandrel tube, and the flow rate was 0.5 L / min. While rotating the mandrel tube at a rotation speed of 25 rpm, light irradiation was performed under the conditions of a metal halide lamp: 160 W / cm, irradiation distance: 120 mm, irradiation intensity: 500 mW / cm ² , and irradiation time: 120 seconds. Thereafter, drying was performed at 130 ° C. for 20 minutes to form a surface cross-linked layer having a thickness of 2.5 μm. Thus, the electrophotographic photosensitive member of Example 1 was produced.

(Example 2)
-Production of electrophotographic photoreceptor-
An electrophotographic photosensitive member was produced in the same manner as in Example 1 except that the temperature of water circulated inside the mandrel tube was changed from 12 ° C. to 17 ° C. in Example 1.

(Example 3)
-Production of electrophotographic photoreceptor-
An electrophotographic photosensitive member was produced in the same manner as in Example 1 except that the temperature of water circulated inside the mandrel tube was changed from 12 ° C. to 22 ° C. in Example 1.

(Comparative Example 1)
-Production of electrophotographic photoreceptor-
An electrophotographic photosensitive member was produced in the same manner as in Example 1 except that the temperature of water circulated inside the mandrel tube was changed from 12 ° C. to 5 ° C. in Example 1.

(Comparative Example 2)
-Production of electrophotographic photoreceptor-
An electrophotographic photosensitive member was produced in the same manner as in Example 1 except that the temperature of water circulated inside the mandrel tube was changed from 12 ° C. to 30 ° C. in Example 1.

Example 4
-Production of electrophotographic photoreceptor-
In Example 1, using the apparatus shown in FIG. 4, an electrophotographic photosensitive member was produced in the same manner as in Example 1 except that water at 12 ° C. was directly circulated inside the photosensitive drum instead of the mandrel tube. did.

(Example 5)
-Production of electrophotographic photoreceptor-
In Example 4, an electrophotographic photosensitive member was produced in the same manner as in Example 4 except that the temperature of the water circulated inside the photosensitive drum was changed from 12 ° C. to 22 ° C.

<Measurement of surface temperature of electrophotographic photoreceptor>
A thermocouple is brought into contact with the surface of the electrophotographic photosensitive drum opposite to the light irradiation surface. The surface temperature of the photosensitive drum at the start of light irradiation (initial surface temperature) and the surface temperature of the photosensitive drum 120 seconds after the light irradiation (maximum) Surface temperature). The results are shown in Table 3.

<Outermost surface film characteristics of photoconductor>
The state of the outermost surface of the photoreceptor was visually observed and evaluated according to the following criteria. The results are shown in Table 3.
〔Evaluation criteria〕
◎: Extremely good ○: Slightly rough ×: Wrinkles are observed

<Actual paper passing test>
Each of the electrophotographic photosensitive members of Examples 1 to 5 and Comparative Examples 1 and 2 produced as described above was tested for 100,000 sheets using an image forming apparatus (manufactured by Ricoh Co., Ltd., imagio Neo C455). (A4 size, manufactured by NBS Ricoh Co., Ltd., MyPaper) was performed, and wear characteristics and image evaluation (a black solid image, a solid white image, a halftone image) were performed as follows. The results are shown in Tables 4 and 5.

<Abrasion characteristics>
The amount of wear on the surface of the photoreceptor after 50,000 sheets and 100,000 sheets with respect to the initial value was determined by the thickness measured by FISCHERSCOPE MMS (Fischer).

<Image evaluation>
The black solid image, the white solid image, and the halftone image after the initial 50,000 sheets and after 100,000 sheets were evaluated according to the following criteria.
〔Evaluation criteria〕
◎: Extremely good ○: Good △: Slightly inferior (actual usable level)
×: Defect

(Example 6)
-Production of electrophotographic photoreceptor-
By sequentially applying an undercoating layer coating solution, a charge generation layer coating solution, and a charge transport layer coating solution having the following composition onto an aluminum cylinder having an outer diameter of 100 mm and a length of 360 mm, and drying. An undercoat layer having a thickness of 1.5 μm, a charge generation layer having a thickness of 0.3 μm, and a charge transport layer having a thickness of 21 μm were formed.

[Composition of undercoat layer coating solution]
Titanium oxide (PT-301, manufactured by Ishihara Sangyo Co., Ltd.) ... 40 parts by mass Alcohol-soluble nylon (CM-8000, manufactured by Toray Industries, Inc.) ... 32 parts by mass Methanol ... 400 parts by mass Isopropanol ... 160 parts by mass

[Composition of charge generation layer coating solution]
-Titanyl phthalocyanine powder of Synthesis Example 1 ... 4 parts by mass-Polyvinyl butyral (ESREC BX-1, manufactured by Sekisui Chemical Co., Ltd.) ... 2 parts by mass-Methyl ethyl ketone ... 150 parts by mass

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

Next, a coating solution for a crosslinked surface layer having the following composition was spray-coated on the obtained charge transport layer.
[Composition of coating solution for crosslinked surface layer]
-Dipentaerythritol hexaacrylate (KAYARAD DPHA, manufactured by Nippon Kayaku Co., Ltd.) as a tri- or higher functional radical polymerizable monomer having no charge transport structure-10 parts by mass-1 represented by the following structural formula Exemplified compound No. 1 as a radical polymerizable compound having a functional charge transporting structure. 105 ... 10 parts by mass
1-hydroxy-cyclohexyl-phenyl ketone (Irgacure 184, manufactured by Ciba Specialty Chemicals) as photopolymerization initiator: 1 part by mass Tetrahydrofuran: 100 parts by mass

Next, after 10-minute touch drying, an aluminum cylinder was attached to the mandrel tube. The length of the mandrel tube was 400 mm, the temperature of the water circulated inside the mandrel tube was 10 ° C., the direction of water circulation was from the lower part to the upper part of the mandrel pipe, and the flow rate was 4 L / min. While rotating the mandrel tube at a rotation speed of 25 rpm, the metal halide lamp was 160 W / cm, the irradiation distance was 120 mm, the irradiation intensity was 500 mW / cm ² , the irradiation time was 240 seconds, and further lighted at 130 ° C. for 20 minutes. Drying was applied to form a surface cross-linked layer having a thickness of 8 μm. Thus, an electrophotographic photosensitive member of Example 6 was produced.

(Example 7)
-Production of electrophotographic photoreceptor-
In Example 6, an electrophotographic photosensitive member was produced in the same manner as in Example 6 except that the flow rate of water circulating inside the mandrel tube was changed from 4 L / min to 2 L / min.

(Example 8)
-Production of electrophotographic photoreceptor-
In Example 6, an electrophotographic photosensitive member was produced in the same manner as in Example 6 except that the flow rate of water circulating inside the mandrel tube was changed from 4 L / min to 1 L / min.

Example 9
-Production of electrophotographic photoreceptor-
In Example 6, it was carried out except that the refrigerant was not flown for 60 seconds from the start of light irradiation, and that silicone oil heated to 100 ° C. was flown into the mandrel tube as a refrigerant until 60 seconds after 60 seconds. In the same manner as in Example 6, an electrophotographic photosensitive member was produced.

(Example 10)
-Production of electrophotographic photoreceptor-
In Example 6, after the light irradiation was started, the refrigerant was not flown for 60 seconds, and the silicone oil heated to 120 ° C. was flown to the inside of the mandrel tube as a refrigerant until 60 seconds after 60 seconds. In the same manner as in Example 6, an electrophotographic photosensitive member was produced.

(Comparative Example 3)
-Production of electrophotographic photoreceptor-
In Example 6, an electrophotographic photosensitive member was produced in the same manner as in Example 6 except that the temperature of water circulated inside the mandrel tube was changed from 10 ° C. to 5 ° C.

(Comparative Example 4)
-Production of electrophotographic photoreceptor-
In Example 6, an electrophotographic photoreceptor was produced in the same manner as in Example 6 except that the temperature of the water circulated inside the mandrel tube was changed from 10 ° C. to 35 ° C.

<Measurement of surface temperature of photoconductor>
For each photoconductor obtained, a thermocouple was brought into contact with the surface of the photoconductor opposite to the light irradiation surface, and the surface temperature of the photoconductor drum at the start of light irradiation (initial surface temperature) and the photoconductor drum after 240 seconds of light irradiation. The surface temperature (maximum surface temperature) was measured. The results are shown in Table 6.

<Outermost surface film characteristics of photoconductor>
The state of the outermost surface of the photoreceptor was visually observed and evaluated according to the following criteria. The results are shown in Table 6.
〔Evaluation criteria〕
◎: Extremely good ○: Slightly rough ×: Wrinkles are observed

<Actual paper passing test>
Each of the electrophotographic photoreceptors of Examples 6 to 10 and Comparative Examples 3 to 4 produced as described above was tested for 3 million sheets using an image forming apparatus (manufactured by Ricoh Co., Ltd., imagio Neo 1050Pro). (A4 size, manufactured by NBS Ricoh Co., Ltd., My Paper), and in the same manner as in Examples 1-5 and Comparative Examples 1-2, wear characteristics and image evaluation (black solid image, white solid image, half Tone image). The results are shown in Table 7 and Table 8.

  The image forming method, the image forming apparatus, and the process cartridge using the electrophotographic photosensitive member of the present invention can be applied to a full-color copying machine, a full-color laser printer, a full-color plain paper fax machine or the like using a direct or indirect electrophotographic multicolor image developing system. Widely used.

FIG. 1 is a schematic view showing an example of a mandrel tube as a cooling means of the electrophotographic photosensitive member of the present invention. FIG. 2 is a schematic diagram showing a refrigerant circulation direction (from bottom to top) inside the mandrel tube. FIG. 3 is a schematic diagram showing the refrigerant circulation direction (from top to bottom) inside the mandrel tube. FIG. 4 is a diagram illustrating an example of a method of flowing a coolant directly into the electrophotographic photosensitive member. FIG. 5 is a schematic sectional view showing an example of the electrophotographic photosensitive member of the present invention. FIG. 6 is a schematic sectional view showing another example of the electrophotographic photosensitive member of the present invention. FIG. 7 is a schematic view showing an example of the image forming apparatus of the present invention. FIG. 8 is a schematic explanatory view showing an example in which the image forming method of the present invention is implemented by the image forming apparatus (tandem color image forming apparatus) of the present invention. FIG. 9 is a partially enlarged schematic explanatory view of the image forming apparatus shown in FIG. FIG. 10 is a schematic view showing an example of the process cartridge of the present invention. FIG. 11 is an X-ray diffraction spectrum of the titanyl phthalocyanine pigment of Synthesis Example 1.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Electrophotographic photosensitive member 2 Static elimination lamp 3 Charger charger 4 Eraser 5 Image exposure part 6 Developing unit 7 Charger before transfer 8 Registration roller 9 Recording medium 10 Electrophotographic photosensitive member 10K Black photosensitive member 10Y Yellow photosensitive member 10M Magenta photosensitive member 10C Cyan Photoconductor 14 Support Roller 15 Support Roller 16 Support Roller 17 Intermediate Transfer Cleaning Device 18 Image Forming Means 20 Charging Roller 21 Exposure Device 22 Secondary Transfer Device 23 Roller 24 Secondary Transfer Belt 25 Fixing Device 26 Fixing Belt 27 Pressure Belt 28 Sheet reversing device 30 Exposure device 32 Contact glass 33 First traveling body 34 Second traveling body 35 Imaging lens 36 Reading sensor 40 Developing device 41 Developing belt 42K Developer accommodating portion 42Y Developer accommodating portion 42M Developer accommodating portion 4 C developer container 43K developer supply roller 43Y developer supply roller 43M developer supply roller 43C developer supply roller 44K developer roller 44Y developer roller 44M developer roller 44C developer roller 45K black developer 45Y yellow developer 45M magenta Developing unit 45C Cyan developing unit 49 Registration roller 50 Intermediate transfer member 51 Roller 52 Separating roller 53 Manual feed path 54 Manual feed tray 55 Switching claw 56 Discharge roller 57 Discharge tray 58 Corona charger 60 Cleaning device 61 Developing device 62 Transfer charger 63 Cleaning device 64 Static elimination device 70 Static elimination lamp 71 Cleaning blade 72 Support member 80 Transfer roller 90 Cleaning device 101 Electrophotographic photosensitive member (photosensitive drum)
DESCRIPTION OF SYMBOLS 102 Charging device 103 Exposure 104 Developing device 105 Recording medium 106 Transfer device 107 Cleaning blade 100 Image forming device 120 Tandem type developer 130 Document table 142 Paper feed roller 143 Paper bank 144 Paper feed cassette 145 Separation roller 146 Paper feed path 147 Conveyance roller 148 Paper feed path 150 Image forming apparatus main body 160 Charging device 200 Paper feed table 201 Mandrel tube 202 Electrophotographic photosensitive member 203 Jig 204 Refrigerant 210 Refrigerant 231 Support 233 Photosensitive layer 235 Charge generation layer 237 Charge transport layer 239 Surface layer 300 Scanner 400 Automatic Document Feeder (ADF)

Claims (16)

A support, and an electrophotographic photoreceptor having at least a photosensitive layer and a surface layer in this order on the support,
The surface layer contains a cured product obtained by curing a radically polymerizable compound having a trifunctional or higher functionality not having a charge transporting structure and a radically polymerizable compound having a charge transporting structure by light irradiation,
An electrophotographic photoreceptor, wherein an initial surface temperature of the electrophotographic photoreceptor at the start of light irradiation is 10 ° C. or more and 25 ° C. or less.   The electrophotographic photosensitive member according to claim 1, wherein the maximum surface temperature of the electrophotographic photosensitive member during light irradiation is 40 ° C or higher and 140 ° C or lower.   3. The electrophotographic photosensitive member according to claim 1, wherein a cooling means is brought into contact with the inside of the electrophotographic photosensitive member to control the surface temperature of the electrophotographic photosensitive member.   4. The electrophotographic photosensitive member according to claim 3, wherein the cooling means is means for introducing a refrigerant whose temperature is controlled in an external thermostat into the mandrel tube and circulating between the thermostat.   The electrophotographic photosensitive member according to claim 4, wherein the refrigerant is one of water and silicone oil.   6. The electrophotographic photosensitive member according to claim 1, wherein the photosensitive layer contains at least a charge generating substance, and the charge generating substance contains titanyl phthalocyanine.   Titanyl phthalocyanine has major peaks with Bragg angle 2θ of at least 9.6 ° ± 0.2 °, 24.0 ° ± 0.2 °, and 27.2 ° ± 0.2 in the X-ray diffraction spectrum for Cu—Kα rays. The electrophotographic photosensitive member according to claim 6, which has a crystal type at 2 °.   The electrophotographic photosensitive member according to claim 1, wherein the photosensitive layer has a laminated structure having at least a charge generation layer and a charge transport layer in this order. A method for producing an electrophotographic photosensitive member having at least a photosensitive layer and a surface layer in this order on a support,
Including at least a surface layer forming step of forming a surface layer by curing a radically polymerizable compound having three or more functional groups having no charge transporting structure and a radical polymerizable compound having a charge transporting structure by light irradiation;
The method for producing an electrophotographic photosensitive member, wherein an initial surface temperature of the electrophotographic photosensitive member at the start of light irradiation is 10 ° C. or higher and 25 ° C. or lower.   The method for producing an electrophotographic photosensitive member according to claim 9, wherein the maximum surface temperature of the electrophotographic photosensitive member during light irradiation is 40 ° C. or higher and 140 ° C. or lower.   The method for producing an electrophotographic photosensitive member according to claim 9, wherein the inner surface of the electrophotographic photosensitive member is brought into contact with a cooling unit to control the surface temperature of the electrophotographic photosensitive member.   12. The method for producing an electrophotographic photosensitive member according to claim 11, wherein the cooling means is a means for introducing a refrigerant whose temperature is controlled in an external thermostat into the mandrel tube and circulating it between the thermostat.   The method for producing an electrophotographic photosensitive member according to claim 12, wherein the refrigerant is any one of water and silicone oil.   9. The electrophotographic photosensitive member according to claim 1, an electrostatic latent image forming unit that forms an electrostatic latent image on the electrophotographic photosensitive member, and developing the electrostatic latent image using toner. And at least developing means for forming a visible image, transfer means for transferring the visible image to a recording medium, and fixing means for fixing the transferred image transferred to the recording medium. Forming equipment.   9. An electrostatic latent image forming step for forming an electrostatic latent image on the electrophotographic photosensitive member according to claim 1; and developing the electrostatic latent image with toner to form a visible image. An image forming method comprising: a developing step for transferring; a transfer step for transferring the visible image to a recording medium; and a fixing step for fixing the transferred image transferred to the recording medium. 9. An electrophotographic photosensitive member according to claim 1, and at least developing means for developing an electrostatic latent image formed on the electrophotographic photosensitive member with toner to form a visible image. A process cartridge which is detachable from the main body of the image forming apparatus.