JP2008129452A - Electrostatic latent image carrier, process cartridge, image forming apparatus and image forming method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electrostatic latent image carrier having a crosslinked surface layer with high scratch and wear resistances and good electrical characteristics and a photosensitive layer, and capable of achieving higher image quality over a long period of time. <P>SOLUTION: The electrostatic latent image carrier has at least the crosslinked surface layer and the photosensitive layer on a support, wherein the crosslinked surface layer contains a reaction product of a tri- or higher functional radically polymerizable compound having no charge transporting structure and a monofunctional radically polymerizable compound having a charge transporting structure, and at least one compound selected from among 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline, 2- (4-t-butylphenyl) -5- (4-biphenylyl) -1,3,4-oxadiazole, 3- (4-t-butylphenyl) -4-phenyl-5- (4-biphenylyl) -1,2,4-triazole and bis (2-methyl-8-quinolinolato) (p-phenylphenolato) aluminum. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an electrostatic latent image carrier, a process cartridge, an image forming apparatus, and an image forming method, and in particular, has a photosensitive layer having high scratch resistance and wear resistance and good electrical characteristics, and has a long period of time. Electrostatic latent image carrier (hereinafter also referred to as "photosensitive member", "electrophotographic photosensitive member", "photoconductive insulator"), and the electrostatic latent image carrier capable of realizing high image quality over a wide range The present invention relates to a process cartridge, an image forming method, and an image forming apparatus.

  In recent years, organic photoreceptors (OPC) have been widely used in copying machines, facsimile machines, laser printers, and composite machines thereof in place of inorganic photoreceptors because of their good performance and various advantages. The 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) selection of materials. Examples include a wide range, (4) ease of production, (5) low cost, and (6) non-toxicity.

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

  Examples of the technique for improving the abrasion resistance of the photosensitive layer described above include (1) using a curable binder in the crosslinkable charge transport layer (see Patent Document 1), and (2) a polymer charge transport material. The ones used (see Patent Document 2), (3) those in which an inorganic filler is dispersed in a cross-linked charge transport layer (see Patent Document 3), and the like have been proposed.

  Among these techniques, those using the curable binder (1) have poor compatibility with the charge transport material, and the residual potential increases due to impurities such as polymerization initiators and unreacted residues. Therefore, the image density tends to decrease. In addition, the use of the polymer type charge transport material (2) can improve the abrasion resistance to some extent, but has yet to fully satisfy the durability required for the organic photoreceptor. Not in. 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 electrical characteristics. Furthermore, there are also problems in production such as a high viscosity of the coating liquid. The dispersion of the inorganic filler (3) exhibits higher wear resistance than a photoreceptor in which a normal low molecular charge transport material is dispersed in an inert polymer, but is present on the surface of the inorganic filler. Due to the charge trapping, the residual potential rises and the image density tends to decrease. In addition, when the unevenness of the inorganic filler and the binder resin on the surface of the photoconductor is large, a cleaning failure may occur, which may cause toner filming or image flow. (1), (2), and ( The technique 3) has not yet satisfied the overall durability including the electrical durability and mechanical durability required for the organic photoreceptor.

  Furthermore, in order to improve the abrasion resistance and scratch resistance of (1) above, a photoreceptor containing a polyfunctional acrylate monomer cured product has been proposed (see Patent Document 4). However, in this photoreceptor, although there is a description that the protective layer provided on the photosensitive layer contains a polyfunctional acrylate monomer cured product, the protective layer may contain a charge transport material. However, when the low-molecular charge transport material is simply contained in the cross-linked charge transport layer, there is a problem of compatibility with the cured product. As a result, precipitation of a low-molecular charge transport material and white turbidity occur, and not only the image density is lowered but also the mechanical strength is lowered due to the increase of the exposed portion potential. In addition, the proposed photoreceptor specifically reacts with a monomer in a state containing a polymer binder, so that the three-dimensional network structure does not proceed sufficiently, and the cross-linking density becomes dilute. It has not yet reached the point where it is possible to exhibit excellent wear resistance.

  Alternative techniques for improving the abrasion resistance of the photosensitive layer include, for example, a coating solution comprising a monomer having a carbon-carbon double bond, a charge transport material having a carbon-carbon double bond, and a binder resin. It has been proposed to provide a charge transport layer formed by using (see Patent Document 5). This proposed binder resin is considered to play a role in improving the adhesion between the charge generation layer and the curable charge transport layer and further reducing the internal stress of the film during thick film curing. And having reactivity with respect to the charge transfer agent and those not having the double bond and not having reactivity. This photoreceptor is noticeable because it has both wear resistance and good electrical characteristics. However, when a non-reactive binder resin is used, the binder resin, the monomer, and the charge transport agent are used. May be poorly compatible with the cured product generated by the reaction with the resin, and phase separation may occur in the cross-linked charge transport layer, which may cause flaws and adhesion of external additives and paper powder in the toner. In addition, as described above, the three-dimensional network structure does not proceed sufficiently and the cross-linking density becomes dilute, so that it has not reached the point where dramatic wear resistance can be exhibited. In addition, what is specifically described as the monomer used in this photoreceptor is bifunctional, and from these reasons, it has not yet been satisfactory in terms of wear resistance. Even when a reactive binder is used, the molecular weight of the cured product is increased, but the number of cross-linking bonds between molecules is small, and it is difficult to achieve both the bonding amount of the charge transport material and the cross-linking density, 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). This photosensitive layer has high hardness because the crosslink density can be increased, but since the bulky hole transporting compound has two or more chain polymerizable functional groups, distortion occurs in the cured product, resulting in high internal stress. Thus, the cross-linked surface layer may easily crack or peel off when used for a long time.
JP 56-48637 A JP-A 64-1728 JP-A-4-281461 Japanese Patent No. 3262488 Japanese Patent No. 3194392 JP 2000-66425 A

  For this reason, the inventor of the present application, as a result of intensive studies, cured at least a trifunctional or higher functional radical polymerizable compound having no charge transport structure and a monofunctional radical polymerizable compound having a charge transport structure on the surface layer. It was found that by using the crosslinked resin layer, electrical characteristics and wear resistance were improved. However, this cross-linked resin layer has insufficient electrical stability in long-term use, and in particular, a decrease in chargeability is confirmed. As a result, an abnormal image can be seen in which the first rotation image of the electrostatic latent image carrier appears as a negative afterimage in the second rotation.

  The reason for this is that the charge transport material and the binder resin are decomposed or altered by NOx and ozone gas generated inside or outside the electrophotographic apparatus, and the material deterioration gradually increases as the current passing through the crosslinked resin layer increases. By proceeding, injection from the surface of the charge in the transfer process having the opposite polarity to the charging process of the electrophotographic apparatus occurs, and after being trapped inside the film of the image carrier, the charge is charged by the second charging process. The release is considered to be a factor, but it was the current situation that no solution could be found.

  Accordingly, an electrostatic latent image carrier that has a photosensitive layer with high scratch resistance and abrasion resistance and good electrical characteristics and that can realize high image quality over a long period of time, and the electrostatic latent image carrier are used. However, an image forming method and related technology that have high durability and can realize a sufficiently high image quality that can be satisfactorily satisfied over a long period of time have not yet been provided, and the rapid development thereof is desired.

  This invention is made | formed in view of this present condition, and makes it a subject to solve the said various problems in the past and to achieve the following objectives. That is, the present invention has an electrostatic latent image carrier that has a crosslinked surface layer having high scratch resistance and abrasion resistance and good electrical characteristics, and a photosensitive layer, and can realize high image quality over a long period of time, and It is an object of the present invention to provide a process cartridge, an image forming method, and an image forming apparatus using the same.

  In order to achieve the above object, the invention according to claim 1 is a latent electrostatic image bearing member comprising a support, and at least a crosslinked surface layer and a photosensitive layer on the support. A reaction product of a trifunctional or higher functional radical polymerizable compound having a charge transporting structure and a monofunctional radical polymerizable compound having a charge transporting structure, and 2,9-dimethyl-4,7-diphenyl; -1,10-phenanthroline and 2- (4-t-butylphenyl) -5- (4-biphenylyl) -1,3,4-oxadiazole and 3- (4-t-butylphenyl) -4-phenyl It contains at least one compound selected from 5- (4-biphenylyl) -1,2,4-triazole and bis (2-methyl-8-quinolinolato) (p-phenylphenolato) aluminum. To.

  The invention according to claim 2 is the electrostatic latent image carrier according to claim 1, wherein the amount of the compound contained in the crosslinked surface layer is 0.2 to 10% by mass. And

  The invention described in claim 3 is the electrostatic latent image carrier according to claim 1 or 2, wherein the functional group of the trifunctional or higher radical polymerizable compound having no charge transport structure is an acryloyloxy group. And a methacryloyloxy group.

  The invention according to claim 4 is the electrostatic latent image bearing member according to any one of claims 1 to 3, wherein the functional group is a functional group in a radically polymerizable compound having three or more functions that does not have the charge transporting structure. The ratio of molecular weight to the number of groups (molecular weight / number of functional groups) is 250 or less.

  The invention according to claim 5 is the electrostatic latent image carrier according to any one of claims 1 to 4, wherein the functional group of the monofunctional radically polymerizable compound having the charge transporting structure is , An acryloyloxy group and a methacryloyloxy group.

  The invention according to claim 6 is the electrostatic latent image bearing member according to any one of claims 1 to 5, wherein the charge transport property of the monofunctional radically polymerizable compound having the charge transport structure is provided. The structure is a triarylamine structure.

  The invention according to claim 7 is the electrostatic latent image carrier according to any one of claims 1 to 6, wherein the monofunctional radically polymerizable compound having the charge transport structure is It is at least one selected from compounds represented by the compounds represented by formulas (1) and (2).

However, in the general formulas (1) and (2), R1 may have a hydrogen atom, a halogen atom, a cyano group, a nitro group, an alkyl group which may have a substituent, or a substituent. Aralkyl group, aryl group which may have a substituent, alkoxy group, —COOR ₇ (where R ₇ may have a hydrogen atom, an alkyl group which may have a substituent, or a substituent. An aralkyl group or an aryl group which may have a substituent, a carbonyl halide group, and —CONR ₈ R ₉ (wherein R ₈ and R ₉ may be the same as or different from each other). Or 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. . Ar ₁ and Ar ₂ may be the same as or different from each other, and represent an arylene group that may have a substituent. Ar ₃ and Ar ₄ may be the same as or different from each other, and each represents an aryl group that may have a substituent. X is a single bond, an alkylene group which may have a substituent, a cycloalkylene group which may have a substituent, an alkylene ether group which may have a substituent, an oxygen atom, a sulfur atom, Represents a vinylene group. 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. m and n represent an integer of 0 to 3.

  The invention according to claim 8 is the electrostatic latent image bearing member according to any one of claims 1 to 7, wherein the monofunctional radically polymerizable compound having the charge transport structure is It includes a compound represented by the formula (3).

  However, in said 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 may be the same as or different from each other, and represent an alkyl group having 1 to 6 carbon atoms. s and t represent the integer of 0-3. Za represents a single bond, a methylene group, an ethylene group, or a substituent represented by the following chemical formulas (4) to (6).

  The invention according to claim 9 is the electrostatic latent image bearing member according to any one of claims 1 to 8, wherein the radical polymerizable compound having a trifunctional or higher functionality having no charge transporting structure is crosslinked. Content in a surface layer is 20-80 mass%, It is characterized by the above-mentioned.

  The invention according to claim 10 is the electrostatic latent image bearing member according to any one of claims 1 to 8, wherein the crosslinked surface layer of the monofunctional radically polymerizable compound having the charge transporting structure. The content in is 20 to 80% by mass.

  According to an eleventh aspect of the present invention, there is provided an electrostatic latent image forming step of forming an electrostatic latent image on an electrostatic latent image carrier, and developing the electrostatic latent image with toner to form a visible image. In the image forming method, the image forming method includes: a developing step for forming a transfer 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. The electrostatic latent image carrier according to any one of claims 1 to 10.

  According to a twelfth aspect of the present invention, there is provided an electrostatic latent image carrier, electrostatic latent image forming means for forming an electrostatic latent image on the electrostatic latent image carrier, and toner. An image forming apparatus comprising: a developing unit that develops a latent image to form a visible image; 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. The electrostatic latent image carrier is the electrostatic latent image carrier according to any one of claims 1 to 10.

  The invention according to claim 13 is the image forming apparatus according to claim 12, wherein the electrostatic latent image forming means includes a charger for charging the surface of the electrostatic latent image carrier, and the electrostatic latent image. And an exposure unit that exposes the surface of the carrier.

  The invention according to claim 14 has an electrostatic latent image carrier and electrostatic latent image forming means for forming an electrostatic latent image on the electrostatic latent image carrier, and further uses toner. Developing means for developing the electrostatic latent image to form a visible image, transfer means for transferring the visible image to a recording medium, and cleaning means for removing toner remaining on the electrostatic latent image carrier. 11. A process cartridge having at least one selected from detachably attached to the main body of the image forming apparatus, wherein the electrostatic latent image carrier is the electrostatic cartridge according to claim 1. It is a latent image carrier.

  According to the present invention, by adopting the above configuration, it is possible to realize a high image quality over a long period of time by having a crosslinked surface layer and a photosensitive layer having high scratch resistance and wear resistance and good electrical characteristics. An electrostatic latent image carrier, a process cartridge using the same, an image forming method, and an image forming apparatus can be provided.

  The inventor of the present application provides a cross-linked resin obtained by curing at least a trifunctional or higher functional radical polymerizable compound having no charge transport structure and a monofunctional radical polymerizable compound having a charge transport structure on the surface layer of the electrostatic latent image carrier. As a result of further studies based on the knowledge that electrical properties and abrasion resistance are improved by forming a layer, 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline ( Structural formula (7) below) and 2- (4-t-butylphenyl) -5- (4-biphenylyl) -1,3,4-oxadiazole (see structural formula (8) below) and 3- ( 4-t-butylphenyl) -4-phenyl-5- (4-biphenylyl) -1,2,4-triazole (see structural formula (9) below) and bis (2-methyl-8-quinolinolato) (p-phenyl) Phenolato By containing at least one compound selected from aluminum (see the following structural formula (10)), the electrical stability is good in long-term use, and the first rotation of the electrostatic latent image carrier. It has been found that it is possible to suppress the occurrence of an abnormal image that appears as a negative afterimage in the second rotation.

  The electrostatic latent image carrier in the embodiment of the present invention includes a support, and at least a crosslinked surface layer and a photosensitive layer on the support, and the crosslinked surface layer does not have a charge transporting structure. It contains a reaction product of a trifunctional or higher functional radical polymerizable compound and a monofunctional radical polymerizable compound having a charge transporting structure, and a compound having a specific structural formula. From this, the electrostatic latent image carrier of the present embodiment has high scratch resistance and wear resistance, and a high durability and high quality image can be obtained over a long period of time.

  Here, the cross-linked surface layer uses a tri- or higher functional radical polymerizable compound, whereby a three-dimensional network structure is developed, and a highly hard cross-linked surface layer having a very high degree of cross-linking is obtained. Abrasion resistance is achieved. On the other hand, when only monofunctional and bifunctional radically polymerizable monomers are used, the cross-linking bond in the cross-linked surface layer becomes dilute, and a dramatic improvement in wear resistance cannot be achieved. When a polymer material is contained in the cross-linked surface layer, the development of the three-dimensional network structure is inhibited and the degree of cross-linking is lowered, so that sufficient wear resistance cannot be obtained as compared with the present invention. Furthermore, the compatibility between the polymer material contained and the cured product resulting from the reaction of the radically polymerizable composition (radically polymerizable monomer or radically polymerizable compound having a charge transporting structure) is poor, and local separation from phase separation occurs. Wears and appears as a scratch on the surface.

  The cross-linked surface layer contains a monofunctional radical polymerizable compound having a charge transporting structure in addition to a trifunctional or higher functional radical polymerizable compound not having a charge transporting structure. These radically polymerizable compounds are incorporated into the cross-linking bond during curing. On the other hand, when a low molecular charge transport material having no functional group is contained in the cross-linked surface layer, precipitation of the low molecular charge transport material and white turbidity occur due to its low compatibility, and the cross-linked surface layer The mechanical strength also decreases. Further, the cross-linked surface layer has a tri- or higher functional radical polymerizable compound having no charge transport structure, a radical polymerizable compound having a charge transport structure, and a total mass of the cross-linked surface layer of 0.2 to 10%. A compound having a specific structural formula contained in mass% is cured by light energy irradiation means. With these radical polymerizable monomers and compounds, radicals are generated by light energy irradiation, and addition polymerization starts. The radical polymerizable monomer and compound cause a chain transfer reaction and a cross-linking reaction, whereby a mechanical strength is improved and a film with small surface irregularities is formed.

  An image forming apparatus according to an embodiment of the present invention includes an electrostatic latent image carrier, an electrostatic latent image forming unit that forms an electrostatic latent image on the electrostatic latent image carrier, and toner. Developing means for developing a latent image to form a visible image, transfer means for transferring the visible image to a recording medium, fixing means for fixing the transferred image transferred to the recording medium, and the electrostatic latent image At least a cleaning means for cleaning the surface of the carrier, and the electrostatic latent image carrier is the electrostatic latent image carrier of the present invention. For this reason, in the image forming apparatus of the present embodiment, the electrostatic latent image carrier of the present invention is used as the electrostatic latent image carrier, so that the scratch resistance and the wear resistance are high, and over a long period of time. High durability and high quality images can be obtained.

  An image forming method according to an embodiment of the present invention includes an electrostatic latent image forming step for forming an electrostatic latent image on an electrostatic latent image carrier, and developing the electrostatic latent image with toner to form a visible image. A developing process for forming the image, a transfer process for transferring the visible image to a recording medium, a fixing process for fixing the transferred image transferred to the recording medium, and a cleaning process for cleaning the electrostatic latent image carrier. The electrostatic latent image carrier is the electrostatic latent image carrier of the present invention. For this reason, in the image forming method of the present embodiment, since the electrostatic latent image carrier of the present invention is used as the electrostatic latent image carrier, scratch resistance and wear resistance are high, and over a long period of time. High durability and high quality images can be obtained.

  A process cartridge according to an embodiment of the present invention includes at least an electrostatic latent image carrier and developing means for developing a latent image formed on the electrostatic latent image carrier with toner to form a visible image. Since the electrostatic latent image carrier to which the present invention is applied is used as the electrostatic latent image carrier, it has high scratch resistance and wear resistance, high durability and high image quality over a long period of time. An image is obtained, and even when blade cleaning or the like is performed, the wear of the electrostatic latent image carrier is extremely suppressed, and the cleaning property is also good.

  Next, the configuration of the electrostatic latent image carrier according to the present invention will be described below.

(Electrostatic latent image carrier)
The electrostatic latent image carrier in the embodiment of the present invention includes a support, and at least a crosslinked surface layer and a photosensitive layer on the support, and further includes other layers as necessary. . The photosensitive layer is not particularly limited and may be appropriately selected depending on the purpose, but may be a single layer type or a laminated type.

  Here, FIG. 1 is a schematic sectional view showing an example of the electrostatic latent image carrier of the present embodiment, and a support 1 and a photosensitive layer having a charge generation function and a charge transport function on the support at the same time. 3 is a photoconductor having a single layer structure having a cross-linked surface layer 4 on the surface of the photosensitive layer 3.

  FIG. 2 is a schematic cross-sectional view showing another example of the electrostatic latent image carrier of the present embodiment. On the support 1, the charge generation layer 2 having a charge generation function on the support, It is a photoreceptor having a laminated structure in which a charge transport layer 5 having a charge transport material function is laminated and a cross-linked surface layer 4 is provided on the surface of the charge transport layer 5.

<Crosslinked surface layer>
The cross-linked surface layer is a layer having a cross-linked structure having at least a charge transport function, and is a tri- or higher functional radical polymerizable compound having at least a charge transport structure and a monofunctional radical polymerizable compound having a charge transport structure. In addition, a compound having a specific structural formula is dissolved or dispersed in a suitable solvent, applied onto the charge transport layer, dried, and then a curing reaction is started by external energy of heat or light irradiation.

  Examples of the trifunctional or higher functional radical polymerizable compound having no charge transporting property include hole transporting structures such as triarylamine, hydrazone, pyrazoline and carbazole, such as condensed polycyclic quinone, diphenoquinone, cyano group and nitro group. A monomer that does not have an 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 is capable of radical polymerization. Examples of these radical polymerizable functional groups include (1) 1-substituted ethylene functional group and (2) 1,1-substituted ethylene functional group shown below.

  (1) As the 1-substituted ethylene functional group, for example, a functional group represented by the following structural formula (11) is preferably exemplified.

[Structural formula]
_{CH 2 = CH-X1- ··· (} 11)

  However, in the structural formula (11), X1 represents an arylene group such as a phenylene group or a naphthylene group which may have a substituent, an alkenylene group which may have a substituent, a —CO— group, — COO- group, -CON (R10)-group (where R10 is a hydrogen atom, an alkyl group such as a methyl group or an ethyl group, an aralkyl group such as a benzyl group, a naphthylmethyl group or a phenethyl group, a phenyl group, a naphthyl group, etc. Or an S-group.

  Specific examples of these substituents include a vinyl group, a styryl group, a 2-methyl-1,3-butadienyl group, a vinylcarbonyl group, an acryloyloxy group, an acryloylamide group, and a vinylthioether group. It is done.

  (2) As the 1,1-substituted ethylene functional group, for example, a functional group represented by the following structural formula (12) is preferably exemplified.

[Structural formula]
_{CH 2 = C (Y) -X2-} ···· (12)

  However, in the structural formula (12), Y represents an alkyl group which may have a substituent, an aralkyl group which may have a substituent, a phenyl group which may have a substituent, or naphthyl. An aryl group such as a group, an alkoxy group such as a halogen atom, a cyano group, a nitro group, a methoxy group or an ethoxy group, a —COO (R11) group (where R11 is a hydrogen atom or a methyl group optionally having substituent (s)) Group, an alkyl group such as an ethyl group, an optionally substituted benzyl, an aralkyl group such as a phenethyl group, an optionally substituted phenyl group, an aryl group such as a naphthyl group, or -CON ( R12) (R13) (wherein R12 and R13 are a hydrogen atom, an optionally substituted methyl group, an alkyl group such as an ethyl group, an optionally substituted benzyl group, a naphthylmethyl group) ,Ah Or an aralkyl group such as a phenethyl group, or an aryl group such as a phenyl group or a naphthyl group which may have a substituent, which may be the same or different from each other), and X2 represents the structural formula ( 11) represents the same substituent, single bond, and alkylene group as X1, provided that at least one of Y and X2 is an oxycarbonyl group, a cyano group, an alkenylene group, and an aromatic ring.

  Examples of these substituents include an α-acryloyloxy chloride group, a methacryloyloxy group, an α-cyanoethylene group, an α-cyanoacryloyloxy group, an α-cyanophenylene group, and a methacryloylamino group. Etc. Examples of the substituent further substituted with the substituent for X and Y include, for example, a halogen atom, a nitro group, an alkyl group such as a cyano group, a methyl group and an ethyl group, an alkoxy group such as a methoxy group and an ethoxy group, Examples thereof include aryloxy groups such as phenoxy group, aryl groups such as phenyl group and naphthyl group, aralkyl groups such as benzyl group and phenethyl group.

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

  Examples of the trifunctional or higher functional radical polymerizable compound having no charge transporting structure include the following, but are not limited to these compounds.

  Examples of the radical polymerizable monomer include trimethylolpropane triacrylate (TMPTA), trimethylolpropane trimethacrylate, trimethylolpropane alkylene-modified triacrylate, trimethylolpropane ethyleneoxy-modified (hereinafter referred to as EO-modified) triacrylate, and triacrylate. Methylolpropylenepropyleneoxy modified (hereinafter referred to as EO modified) triacrylate, trimethylolpropane caprolactone modified triacrylate, trimethylolpropane alkylene modified trimethacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate (PETTA), glycerol triacrylate, glycerol epi Chlorohydrin modified (hereinafter referred to as ECH modified) triacryle Glycerol EO modified triacrylate, glycerol PO modified triacrylate, tris (acryloxyethyl) isocyanurate, dipentaerythritol hexaacrylate (DPHA), dipentaerythritol caprolactone modified hexaacrylate, dipentaerythritol hydroxypentaacrylate, alkylated di Pentaerythritol pentaacrylate, alkylated dipentaerythritol tetraacrylate, alkylated dipentaerythritol triacrylate, dimethylolpropane tetraacrylate (DTMPTA), pentaerythritol ethoxytetraacrylate, phosphoric acid EO-modified triacrylate, 2, 2, 5, 5 , -Tetrahydroxymethylcyclopentanone tetraacrylate, etc. Gerare, these may be used alone or in combination of two or more thereof.

  The trifunctional or higher functional radical polymerizable compound having no charge transporting structure forms a dense cross-linked bond in the cross-linked surface layer. Therefore, the ratio of molecular weight to the number of functional groups in the monomer (molecular weight / number of functional groups) is 250 or less is preferable. When the ratio of the molecular weight to the number of functional groups in the monomer exceeds 250, the crosslinked surface layer is soft and wear resistance is somewhat lowered. Therefore, among the monomers exemplified above, a monomer having a modifying group such as EO, PO, caprolactone, etc. In the method, it is not preferable to use a compound having an extremely long modifying group alone.

  Further, the content of the trifunctional or higher functional radical polymerizable compound having no charge transport structure used in the crosslinked surface layer is preferably 20 to 80% by mass, and 30 to 70% by mass with respect to the total amount of the crosslinked surface layer. More preferred. When the content is less than 20% by mass, the three-dimensional cross-linking density of the cross-linked surface layer is small, 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 charge transporting compound is lowered, and the electrical characteristics are deteriorated. The electrical characteristics and abrasion resistance required vary depending on the process used, and the film thickness of the crosslinked surface layer of the photoreceptor varies accordingly. A range of mass% is most preferred.

  The monofunctional radically polymerizable compound having a charge transporting structure used for the crosslinked surface layer is, for example, a hole transporting structure such as triarylamine, hydrazone, pyrazoline, carbazole, such as condensed polycyclic quinone, diphenoquinone. And a compound having an electron transport structure such as an electron-withdrawing aromatic ring having a cyano group or a nitro group and having one radical polymerizable functional group. Examples of the radical polymerizable functional group include those shown in the above radical polymerizable monomer, and acryloyloxy group and methacryloyloxy group are particularly useful. As the charge transporting structure, a triarylamine structure can be obtained with a high effect. In particular, when a compound represented by the following general formula (1) or (2) is used, sensitivity, residual potential, etc. The electrical characteristics of are maintained well.

In the general formulas (1) and (2), R ₁ is a hydrogen atom, a halogen atom, a cyano group, a nitro group, an alkyl group which may have a substituent, or an aralkyl which may have a substituent. Group, aryl group optionally having substituent (s), alkoxy group, —COO (R7) (provided that R7 may have a hydrogen atom, an alkyl group optionally having substituent (s), or a substituent). An aralkyl group or an aryl group which may have a substituent), a carbonyl halide group, and CON (R8) (R9) (provided that R8 and R9 may be the same or different from each other); Or 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. . Ar ₁ and Ar ₂ may be the same as or different from each other, and represent an arylene group that may have a substituent. Ar ₃ and Ar ₄ may be the same as or different from each other, and each represents an aryl group that may have a substituent. X is a single bond, an alkylene group which may have a substituent, a cycloalkylene group which may have a substituent, an alkylene ether group which may have a substituent, an oxygen atom, a sulfur atom, Represents a vinylene group. 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. m and n represent an integer of 0 to 3.

In the general formula (1) or (2), in the substituent of R1, examples of the alkyl group include a methyl group, an ethyl group, a propyl group, and a butyl group, and 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, and 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. Among the substituents for R ₁ , particularly preferred are a hydrogen atom and a methyl group. Substituted or unsubstituted Ar ₃ and Ar ₄ are aryl groups, and examples of the aryl group include a condensed polycyclic hydrocarbon group, a non-fused cyclic hydrocarbon group, and a heterocyclic group.

  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. Moreover, the aryl groups represented by Ar ₃ and Ar ₄ may have substituents as shown in the following (1) to (8), for example.

  (1) A halogen atom, a cyano group, a nitro group, etc. are mentioned.

  (2) Alkyl groups, preferably C1-C12, especially C1-C8, more preferably C1-C4 linear or branched alkyl groups, and these alkyl groups further include a fluorine atom, a hydroxyl group, a cyano group, It may have a phenyl group substituted with a C1-C4 alkoxy group, a phenyl group or a halogen atom, a C1-C4 alkyl group or a C1-C4 alkoxy group. 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-ethoxy Examples include an ethyl 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 (—O (R2)), wherein R2 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 , A trifluoromethoxy group, and the like.

  (4) An aryloxy group, and examples of the aryl group include a phenyl group and a naphthyl group. This may contain a C1-C4 alkoxy group, a C1-C4 alkyl group or a halogen atom as a substituent. Specific examples include phenoxy group, 1-naphthyloxy group, 2-naphthyloxy group, 4-methoxyphenoxy group, 4-methylphenoxy group, and the like.

  (5) Alkyl mercapto group or aryl mercapto group, and specific examples include methylthio group, ethylthio group, phenylthio group, p-methylphenylthio group, and the like.

  (6) Examples include groups represented by the following general formula (13).

In the general formula (13), R ₃ and R ₄ each independently represent a hydrogen atom, an alkyl group defined in the above (2), or an aryl group. Examples of the aryl group include a phenyl group, a biphenyl group, and a naphthyl group, which 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 And pyrrolidino group.

  (7) An alkylenedioxy group or an alkylenedithio group such as a methylenedioxy group or a methylenedithio group.

  (8) Substituted or unsubstituted styryl group, substituted or unsubstituted β-phenylstyryl group, diphenylaminophenyl group, ditolylaminophenyl group, and the like.

In the general formula (1), the arylene group represented by Ar ₁ or Ar ₂ is a divalent group derived from the aryl group represented by Ar ₃ or Ar ₄ .

  X in the general formula (1) represents a single bond, a substituted or unsubstituted alkylene group, a substituted or unsubstituted cycloalkylene group, a substituted or unsubstituted alkylene ether group, an oxygen atom, a sulfur atom, or a vinylene group. The substituted or unsubstituted alkylene group is a C1-C12, preferably C1-C8, more preferably a C1-C4 linear or branched alkylene group, and these alkylene groups further include a fluorine atom, a hydroxyl group, It may have a phenyl group substituted with a cyano group, a C1-C4 alkoxy group, a phenyl group or a halogen atom, a C1-C4 alkyl group or a C1-C4 alkoxy 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 substituted or unsubstituted cycloalkylene group is a C5-C7 cyclic alkylene group, and these cyclic alkylene groups have a fluorine atom, a hydroxyl group, a C1-C4 alkyl group, and a C1-C4 alkoxy group. May be. Specific examples include a cyclohexylidene group, a cyclohexylene group, and a 3,3-dimethylcyclohexylidene group.

  The substituted or unsubstituted alkylene ether group represents ethyleneoxy, propyleneoxy, ethylene glycol, propylene glycol, diethylene glycol, tetraethylene glycol, tripropylene glycol, and the alkylene ether group alkylene group is a hydroxyl group, a methyl group, an ethyl group, etc. You may have the substituent of. As the vinylene group, groups represented by the following general formulas (14) and (15) are preferable.

However, in the structural formula, R ₅ is hydrogen, an alkyl group (same as the groups defined in (2)), an aryl group (said Ar _3, Ar ₄ same as the aryl group represented by) , A represents 1 or 2, and b represents 1-3.

  Z in the general formulas (1) and (2) represents a substituted or unsubstituted alkylene group, a substituted or unsubstituted alkylene ether divalent group, or an alkyleneoxycarbonyl divalent group. Examples of the substituted or unsubstituted alkylene group include the same alkylene groups as those described above for X. Examples of the substituted or unsubstituted alkylene ether divalent group include the divalent group of the alkylene ether group of X. Examples of the alkyleneoxycarbonyl divalent group include a caprolactone-modified divalent group.

  The monofunctional radically polymerizable compound having the charge transporting structure is more preferably a compound 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 may be the same as or different from each other, and represent an alkyl group having 1 to 6 carbon atoms. s and t represent the integer of 0-3. Za represents a single bond, a methylene group, an ethylene group, or a substituent represented by the following structural formula. In addition, as a compound represented by the said General formula (3), a methyl group and an ethyl group are especially preferable as a substituent of Rb and Rc.

  The radically polymerizable compound having a monofunctional charge transporting structure represented by the general formulas (1), (2) and (3), particularly the general formula (3) is a carbon-carbon double compound. Since the bonds are released on both sides and polymerize, it does not become a terminal structure, but is incorporated into a chain polymer and crosslinked by polymerization with a trifunctional or higher functional polymerizable compound. Present in the main chain and present in the cross-linked chain between the main chain and main chain (this cross-linked chain is intermolecular cross-linked between one polymer and the other polymer and folded within one polymer. When there is an intramolecular cross-linked chain that crosslinks a part of the main chain in a separated state and another part derived from the polymerized monomer at a position away from this in the main chain) Or a triarylamine suspended from a chain moiety, whether present in a bridged chain The structure has at least three aryl groups arranged in a radial direction from the nitrogen atom and is bulky, but is not directly bonded to the chain part but suspended from the chain part via a carbonyl group or the like. Since these triarylamine structures can be arranged adjacent to each other in the polymer, there is little structural distortion in the molecule. In the case of a crosslinked surface layer of a photographic photoreceptor, it is presumed that an intramolecular structure that is relatively free from interruption of the charge transport path can be adopted.

  Specific examples of the monofunctional radically polymerizable compound having a charge transporting structure in the present embodiment are shown in Tables 1 to 25 below, but are not limited to the compounds having these structures.

  The radical polymerizable compound having the monofunctional charge transporting structure is important for imparting the charge transport performance of the crosslinked surface layer. The addition amount of the monofunctional radically polymerizable compound having the charge transporting structure is preferably 20 to 80% by mass, more preferably 30 to 70% by mass with respect to the crosslinked surface layer. When the addition amount is less than 20% by mass, the charge transport performance of the crosslinked surface layer cannot be maintained sufficiently, and deterioration of electrical characteristics such as a decrease in sensitivity and an increase in residual potential may occur due to repeated use. If it exceeds 50%, the content of the trifunctional monomer having no charge transporting structure is lowered, and the crosslink density is lowered, and high wear resistance may not be exhibited. The required electrical characteristics and abrasion resistance differ depending on the process used, and the film thickness of the crosslinked surface layer of the photoreceptor varies accordingly. A range of mass% is most preferred.

  In addition, the crosslinked surface layer in the present embodiment includes at least a trifunctional or higher functional radical polymerizable compound having no charge transport structure, a monofunctional radical polymerizable compound having a charge transport structure, and the following chemical formulas (7) to (7): 10). A compound obtained by curing 10).

  In the case where the crosslinked surface layer contains a compound having the above chemical formula, in particular, the image of the first rotation of the electrostatic latent image carrier is an afterimage (particularly in a form in which the density is low with respect to the surroundings and characters are missing). It is possible to suppress abnormal images appearing as negative afterimages appearing in The reason for this is presumed to be derived from the suppression of the injection of charges from the surface in the transfer step, which has the opposite polarity to the charging step of the electrophotographic apparatus. The compound is contained in at least one kind, and can contain a plurality of compounds. Further, when the addition amount contained in the crosslinked surface layer is less than 0.2% by mass, the effect on the negative afterimage is poor, and when it is more than 10% by mass, a side effect of reducing wear resistance is observed. 2-10 mass% is desirable.

  The crosslinked surface layer is obtained by curing at least a trifunctional or higher functional radical polymerizable compound having no charge transport structure, a monofunctional radical polymerizable compound having a charge transport structure, and a compound having a specific structural formula. In addition to this, monofunctional and bifunctional radically polymerizable monomers and radical polymerization for the purpose of imparting functions such as viscosity adjustment during coating, stress relaxation of the cross-linked surface layer, lower surface energy and reduction of friction coefficient, etc. Can be used in combination. Known radical polymerizable monomers and oligomers can be used.

  Examples of the monofunctional radical monomer include 2-ethylhexyl acrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, hydroxypropyl acrylate, tetrahydrofurfuryl acrylate, 2-ethylhexyl carbitol acrylate, and 3-methoxybutyl acrylate. 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, and the like. Siloxane repeating units described in JP-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 oligomer include epoxy acrylate, urethane acrylate, and polyester acrylate oligomers.

  The content of the monofunctional and bifunctional radically polymerizable monomer or radically polymerizable oligomer is preferably 50 parts by mass or less, more preferably 30 parts by mass or less, based on 100 parts by mass of the trifunctional or higher functional radical polymerizable compound. If the content exceeds 50 parts by mass, the three-dimensional cross-linking density of the cross-linked surface layer may be substantially reduced, resulting in a decrease in wear resistance.

  The crosslinked surface layer in the present embodiment may contain an antioxidant as necessary. There is no restriction | limiting in particular as antioxidant, It can select suitably according to the objective from what is known as antioxidants, such as rubber | gum, a plastics, and fats and oils, for example, a phenol type compound, paraphenylenediamine , Hydroquinones, organic sulfur compounds, organic phosphorus compounds, and the like. These may be used individually by 1 type and may use 2 or more types together.

  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] cricol 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 thereof 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, dimyristyl-3,3′-thiodipropionate, and ditetradecyl-3. , 3′-thiodipropionate, pentaerythritol tetrakis (3-laurylthiopropionate), and the like.

  Examples of the organic phosphorus compounds include triphenyl phosphite, tris (nonylphenyl) phosphite, tri (dinonylphenyl) phosphite, tris (2-ethylhexyl) phosphite, tridecyl phosphite, and tris (tridecyl). Phosphite, diphenyl mono (2-ethylhexyl) phosphite, diphenyl monodecyl phosphite, tris (2,4, di-t-butylphenyl) phosphite, distearyl pentaerythritol diphosphite, bis (2, 4, di-t -Butylphenyl) pentaerythritol phosphite, 2,2-methylenebis (4,6-di-t-butylphenyl) octyl phosphite, tetrakis (2,4-di-t-butylphenyl) 4,4'-biphenylene-diphospho Knight, dilauryl Hydrogen phosphite, diphenyl hydrogen phosphite, tetraphenyldipropylene glycol diphosphite, tetraphenyltetra (tridecyl) pentaerythritol tetraphosphite, tetra (tridecyl) -4,4′isopropylidenediphenyl diphosphite, bis (nonylphenyl) ) Pentaerythritol diphosphite, hydrogenated bisphenol A / pentaerythritol phosphite polymer, and the like.

  The crosslinked surface layer is obtained by curing at least a trifunctional or higher functional radical polymerizable compound having no charge transport structure and a monofunctional radical polymerizable compound having a charge transport structure. In order to advance the curing reaction efficiently, a polymerization initiator may be contained in the crosslinked surface layer coating solution. Examples of the polymerization initiator include a thermal polymerization initiator and a photopolymerization initiator. These polymerization initiators may be used alone or in combination of two or more.

  Examples of the thermal polymerization initiator include 2,5-dimethylhexane-2,5-dihydroperoxide, dicumyl peroxide, benzoyl peroxide, t-butylcumyl peroxide, 2,5-dimethyl-2,5. -Di (peroxybenzoyl) hexyne-3, di-t-butyl peroxide, t-butyl hydroperoxide, cumene hydroperoxide, lauroyl peroxide, 2,2-bis (4,4-di-t-butyl Peroxycyclohexyl) propane and other peroxide initiators; azobisisobutylnitrile, azobiscyclohexanecarbonitrile, methyl azobisisobutyrate, azobisisobutylamidine hydrochloride, 4,4′-azobis-4-cyanovaleric acid, etc. And azo initiators.

  Examples of the photopolymerization initiator include diethoxyacetophenone, 2,2-dimethoxy-1,2-diphenylethane-1-one, 1-hydroxy-cyclohexyl-phenyl-ketone, and 4- (2-hydroxyethoxy) phenyl. -(2-hydroxy-2-propyl) ketone, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) butanone-1,2-hydroxy-2-methyl-1-phenylpropan-1-one Acetophenone-based or ketal-based photopolymerization of 2-methyl-2-morpholino (4-methylthiophenyl) propan-1-one, 1-phenyl-1,2-propanedione-2- (o-ethoxycarbonyl) oxime, etc. Agents: benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isobuty Benzoin ether photopolymerization initiators such as ether and benzoin isopropyl ether; benzophenone, 4-hydroxybenzophenone, methyl o-benzoylbenzoate, 2-benzoylnaphthalene, 4-benzoylbiphenyl, 4-benzoylphenyl ether, acrylated benzophenone, 1 Benzophenone photopolymerization initiators such as 1,4-benzoylbenzene; thioxanthone photopolymerization such as 2-isopropylthioxanthone, 2-chlorothioxanthone, 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2,4-dichlorothioxanthone Initiators; Other photopolymerization initiators include ethyl anthraquinone, 2,4,6-trimethylbenzoyl diphenylphosphine oxide, 2,4,6-trimethylbenzoylphenol Ruethoxyphosphine oxide, bis (2,4,6-trimethylbenzoyl) phenylphosphine oxide, bis (2,4-dimethoxybenzoyl) -2,4,4-trimethylpentylphosphine oxide, methylphenylglyoxyester, 9,10 -Phenanthrene, an acridine type compound, a triazine type compound, an imidazole type compound, etc. are mentioned.

  In addition, what has a photopolymerization acceleration effect can also be used individually or in combination with the said photoinitiator. Examples include triethanolamine, methyldiethanolamine, ethyl 4-dimethylaminobenzoate, isoamyl 4-dimethylaminobenzoate, (2-dimethylamino) ethyl benzoate, 4,4′-dimethylaminobenzophenone, and the like. The content of the polymerization 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 content having radical polymerizability.

  The cross-linked surface layer coating liquid may contain additives such as various plasticizers, leveling agents, and low molecular charge transport materials having no radical reactivity for the purpose of stress relaxation and adhesion improvement, as necessary. As the plasticizer, for example, those used in general resins such as dibutyl phthalate and dioctyl phthalate can be used. 20 mass% or less is preferable with respect to the total solid of the said coating liquid for bridge | crosslinking surface layers, and, as for the usage-amount of the said plasticizer, 10 mass% or less is more preferable.

  Examples of the leveling agent include silicone oils such as dimethyl silicone oil and methylphenyl silicone oil, and polymers or oligomers having a perfluoroalkyl group in the side chain. The amount of the leveling agent used is preferably 3% by mass or less based on the total solid content of the crosslinked surface layer coating solution.

  The cross-linked surface layer is a coating containing at least a trifunctional or higher functional radical polymerizable compound having no charge transport structure, a monofunctional radical polymerizable compound having a charge transport structure, and a compound having a specific structural formula. It is formed by applying and curing the working liquid on the charge transport layer described later. When the radically polymerizable monomer is a liquid, the coating liquid can be applied by dissolving other components in the liquid, but it is further diluted with a solvent as required.

  Examples of the solvent include alcohol solvents such as methanol, ethanol, propanol, butanol; ketone solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone; ester solvents such as ethyl acetate and butyl acetate; tetrahydrofuran, dioxane, Ether solvents such as propyl ether; halogen solvents such as dichloromethane, dichloroethane, trichloroethane, chlorobenzene; aromatic solvents such as benzene, toluene, xylene; cellosolv solvents such as methyl cellosolve, ethyl cellosolve, cellosolve acetate, etc. It is done. These may be used individually by 1 type and may use 2 or more types together. The dilution ratio with the solvent varies depending on the solubility of the composition, the coating method, and the target film thickness, and is arbitrary. The coating can be performed using a dip coating method, spray coating, bead coating, ring coating method or the like.

  In this embodiment, after applying the above-mentioned crosslinked surface layer coating solution, energy is applied from the outside and cured to form a crosslinked surface layer. The external energy used at this time is heat, light, radiation, etc. There is. The heat energy is applied by heating from the coating surface side or the support side using air, a gas such as nitrogen, steam, various heat media, infrared rays, or electromagnetic waves.

  The heating temperature is preferably 100 to 170 ° C. When the heating temperature is less than 100 ° C., the reaction rate is slow and the curing reaction may not be completed completely. When the heating temperature is higher than 170 ° C., the temperature becomes too high and the curing reaction proceeds non-uniformly. Large distortion, a large number of unreacted residues, and reaction termination ends may occur. In order to advance the curing reaction uniformly, it is also effective to complete the reaction by heating at a relatively low temperature of less than 100 ° C. and then heating to 100 ° C. or more.

  As the energy of the light, 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, but a visible light source according to the absorption wavelength of a radical polymerizable substance or a photopolymerization initiator. It is also possible to select. The irradiation light amount is preferably 50 to 1000 mW / cm 2. When the irradiation light quantity is less than 50 mW / cm 2, it may take time for the curing reaction, and when it exceeds 1000 mW / cm 2, the progress of the reaction becomes non-uniform and local wrinkles occur on the surface of the crosslinked surface layer. , Many unreacted residues and reaction termination ends may occur. In addition, internal stress increases due to rapid crosslinking, which causes cracks and film peeling.

  Examples of the energy of the radiation include those using an electron beam. Among these energies, those using heat and light energy are useful because of the ease of reaction rate control and the simplicity of the apparatus.

  In addition to the trifunctional or higher functional radical polymerizable compound not having the charge transporting structure and the monofunctional radical polymerizable compound having the charge transporting structure, the crosslinking surface layer coating liquid may include radicals as other components. Additives such as a binder resin having no polymerizable functional group, an antioxidant, and a plasticizer can be included.

  When these additives are contained in a large amount, the crosslinking density is reduced, the cured product generated by the reaction and the additive are phase-separated, and become soluble in an organic solvent. Specifically, it is important to suppress the total content to 20% by mass or less with respect to the total solid content of the coating liquid. Further, in order not to dilute the crosslinking density, the total content of monofunctional or bifunctional radically polymerizable monomer, reactive oligomer, and reactive polymer is 20% by mass or less based on the trifunctional radically polymerizable monomer. It is desirable to do. Further, when a large amount of a radical polymerizable compound having a bifunctional or higher functional charge transporting structure is contained, a bulky structure is fixed in the crosslinked structure by a plurality of bonds, so that distortion is likely to occur. It is easy to become an aggregate. This can cause solubility in organic solvents. Although different depending on the compound structure, the content of the radical polymerizable compound having a bifunctional or higher charge transporting structure is preferably 10% by mass or less based on the monofunctional radical polymerizable compound having a charge transporting structure. Furthermore, in the structure in which the charge generation layer, the charge transport layer, and the crosslinked surface layer are sequentially laminated, it is preferable that the outermost crosslinked surface layer is insoluble in the organic solvent in order to achieve wear resistance and scratch resistance.

  In this embodiment, in order to make the crosslinked surface layer insoluble in the organic solvent, (i) the composition of the crosslinked surface layer coating solution, adjustment of the content ratio thereof, and (ii) the crosslinked surface layer coating solution. Dilution solvent, adjustment of solid content concentration, (iii) selection of coating method of crosslinked surface layer, (iv) control of curing condition of crosslinked surface layer, and (v) poor solubility of charge transport layer in lower layer, etc. Is important, but is not always achieved with a single factor.

  As a diluent solvent for the crosslinked surface layer coating solution, when a solvent having a low evaporation rate is used, the remaining solvent may hinder the curing or increase the amount of the lower layer component mixed. It leads to uniform curing and reduced curing density. For this reason, it tends to be soluble in organic solvents. Specifically, tetrahydrofuran, a mixed solvent of tetrahydrofuran and methanol, ethyl acetate, methyl ethyl ketone, ethyl cellosolve and the like are useful, but are selected according to the coating method. Moreover, regarding the solid content concentration, if it is too low for the same reason, it tends to be soluble in an organic solvent. On the contrary, the upper limit concentration may be restricted due to the limitation of the film thickness and the coating solution viscosity, and specifically, it is desirably used in the range of 10 to 50% by mass.

  As the coating method of the crosslinked surface layer, a solvent content at the time of forming the coating film, a method of reducing the contact time with the solvent is preferable, specifically, a spray coating method, a ring that regulates the amount of coating liquid A coating method is particularly preferred. In order to suppress the amount of the lower layer component to be mixed, it is also effective to use a polymer charge transport material as the charge transport layer and to provide an insoluble intermediate layer with respect to the coating solvent for the crosslinked surface layer.

  As the curing conditions for the pre-crosslinked surface layer, if the energy of heating or light irradiation is low, the curing is not completely completed and the solubility in the organic solvent is increased. On the other hand, when cured with very high energy, the curing reaction becomes non-uniform, which tends to increase the number of uncrosslinked parts and radical stopping parts, or to form an aggregate of minute cured products. For this reason, it may become soluble in an organic solvent.

  In order to insolubilize the organic solvent, the heat curing conditions are preferably 100 to 170 ° C. and 10 minutes to 3 hours, and the curing conditions by UV light irradiation are 50 to 1000 mW / cm 2 and 5 seconds to 5 minutes. In addition, it is desirable to control the temperature rise to 50 ° C. or less to suppress uneven curing reaction.

As a method for making the crosslinked surface layer insoluble in an organic solvent, for example, when using an acrylate monomer having three acryloyloxy groups and a triarylamine compound having one acryloyloxy group as a coating liquid, These use ratios are preferably 7: 3 to 3: 7. The polymerization initiator is used in an amount of 3 to 20 with respect to the total amount of these acrylate compounds.
It is preferable to add a mass% and further add a solvent to prepare a coating solution. For example, in the case where the surface transport layer is formed by spray coating using a triarylamine donor as the charge transport material and a polycarbonate resin as the binder resin in the charge transport layer which is the lower layer of the cross-linked surface layer, the above coating liquid As the solvent, tetrahydrofuran, 2-butanone, ethyl acetate and the like are preferable. The use ratio is 3 to 10 times the total amount of the acrylate compound.

  Next, for example, the prepared coating solution is applied by spraying or the like on a photoreceptor in which an undercoat layer, a charge generation layer, and the charge transport layer are sequentially laminated on a support such as an aluminum cylinder. Thereafter, it is naturally dried or dried at a relatively low temperature for a short time (25 to 80 ° C., 1 to 10 minutes) and cured by UV irradiation or heating.

  In the case of UV irradiation, a metal halide lamp or the like is used, but the illuminance is preferably 50 mW / cm 2 or more and 1000 mW / cm 2 or less. For example, when irradiating UV light of 200 mW / cm 2, Irradiation may be performed uniformly for about 30 seconds. At this time, the drum temperature is controlled so as not to exceed 50 ° C.

  In the case of thermosetting, the heating temperature is preferably 100 to 170 ° C. For example, when a blow type oven is used as the heating means and the heating temperature is set to 150 ° C., the heating time is 20 minutes to 3 hours. After completion of the curing, the electrostatic latent image carrier of this embodiment is obtained by further heating at 100 to 150 ° C. for 10 to 30 minutes to reduce the residual solvent.

<Support>
The support is not particularly limited as long as it has a volume resistance of 10 ¹⁰ Ω · cm or less, and can be appropriately selected according to the purpose. For example, aluminum, nickel, chromium, nichrome, copper Metals such as gold, silver, platinum, etc .; metal oxides such as tin oxide and indium oxide deposited by vapor deposition or sputtering, coated with paper or paper, or aluminum, aluminum alloy, nickel, stainless steel, etc. And a tube subjected to surface treatment such as cutting, super-finishing, polishing, etc. can be used. Further, an endless nickel belt and an endless stainless steel belt described in JP-A-52-36016 can also be used as a support. In addition, what coated and disperse | distributed conductive powder to the appropriate binder resin on the said support body can also be used as a support body of this embodiment.

  Examples of the conductive powder include carbon black, acetylene black, metal powder such as aluminum, nickel, iron, nichrome, copper, zinc, and silver, or metal oxide powder such as conductive tin oxide and ITO. Etc. The binder resin used at the same time includes polystyrene resin, styrene-acrylonitrile copolymer, styrene-butadiene copolymer, styrene-maleic anhydride copolymer, polyester resin, polyvinyl chloride resin, vinyl chloride-vinyl acetate. 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, Thermoplastic, thermosetting resin, or photocurable resin such as acrylic resin, silicone resin, epoxy resin, melamine resin, urethane resin, phenol resin, alkyd resin, and the like can be given. The conductive layer can be provided by dispersing and applying these conductive powder and binder resin in a suitable solvent such as tetrahydrofuran, dichloromethane, methyl ethyl ketone, and toluene.

  Furthermore, it is conductive by a heat-shrinkable tube in which the conductive powder is contained in a material such as polyvinyl chloride, polypropylene, polyester, polystyrene, polyvinylidene chloride, polyethylene, chlorinated rubber, Teflon (registered trademark) on a suitable cylindrical substrate. Those provided with a conductive layer can also be used favorably as the conductive support of the present embodiment.

<Photosensitive layer of laminated structure>
In the case of a laminated structure, the photosensitive layer has at least a charge generation layer having a charge generation function, a charge transport layer having a charge transport material function in this order, and further includes other layers as necessary. Become. In this case, either the aspect in which the entire charge transport layer is a crosslinked surface layer or the aspect in which the surface portion of the charge transport layer is a crosslinked surface layer is preferable.

  First, regarding the charge generation layer, the charge generation layer includes a charge generation material having a charge generation function as a main component, and further includes a binder resin and, if necessary, other components. As the charge generation material, both inorganic materials and organic materials can be suitably used. Examples of the inorganic material include crystalline selenium, amorphous selenium, selenium-tellurium, selenium-tellurium-halogen, selenium-arsenic compound, and amorphous silicone. As the amorphous silicone, those obtained by terminating dangling bonds with hydrogen atoms or halogen atoms, or those doped with boron atoms, phosphorus atoms or the like are preferably used.

  A known material can be used as the organic material. For example, phthalocyanine pigments such as metal phthalocyanine and metal-free phthalocyanine; azulenium salt pigments, squaric acid methine pigments, azo pigments having carbazole skeleton, azo pigments having triphenylamine skeleton, azo pigments having diphenylamine skeleton, dibenzothiophene skeleton Azo pigments having a fluorenone skeleton, azo pigments having an oxadiazole skeleton, azo pigments having a bis-stilbene skeleton, azo pigments having a distyryl oxadiazole skeleton, azo pigments having a distyrylcarbazole skeleton, perylene Pigments, anthraquinone or polycyclic quinone pigments, quinoneimine pigments, diphenylmethane or triphenylmethane pigments, benzoquinone or naphthoquinone pigments, cyanine or azomethine pigments, indigo Id based pigments, bisbenzimidazole pigments. These charge generation materials can be used alone or as a mixture of two or more. Among these, oxytitanium phthalocyanine represented by the following general formula (179) is one of the preferable ones.

  In the general formula (179), X1, X2, X3, and X4 represent Cl or Br. h, i, j, and k represent an integer of 0 to 4.

  The crystal form of the oxytitanium phthalocyanine is not particularly limited and may be appropriately selected depending on the intended purpose. The black angle (2θ ± 0.2 °) in the characteristic X-ray diffraction of CuKα is 9.0 °, Sensitivity is either oxytitanium phthalocyanine having strong peaks at 14.2 °, 23.9 ° and 27.1 °, or oxytitanium phthalocyanine having strong peaks at 9.6 ° and 27.3 °. It is more preferable from the viewpoint of characteristics.

  Examples of the binder resin include polyamide, polyurethane, epoxy resin, polyketone, polycarbonate, silicone resin, acrylic resin, polyvinyl butyral, polyvinyl formal, polyvinyl ketone, polystyrene, poly-N-vinylcarbazole, polyacrylamide, and the like. These can be used alone or as a mixture of two or more. Specifically, JP-A-01-001728, JP-A-01-009964, JP-A-01-013061, JP-A-01-019049, JP-A-01-241559, JP-A-04-011627. JP, 04-175337, JP 04-183719, JP 04-22514, JP 04-230767, JP 04-320420, 05-232727. JP, 05-310904, JP 06-234836, JP 06-234837, JP 06-234838, JP 06-234839, JP 06-234840, Japanese Laid-Open Patent Application Nos. 06-234841, 06-239049, 06-2 JP 6050, JP 06-236051, JP 06-295077, JP 07-056374, JP 08-176293, JP 08-208820, JP 08-21640. JP, 08-253568, JP 08-269183, JP 09-062019, JP 09-038883, JP 09-71642, JP 09-87376, JP-A 09-104746, JP-A 09-110974, JP-A 09-110976, JP-A 09-157378, JP-A 09-221544, JP-A 09-227669, JP 09-235367, JP 09-241369 A, JP 09-09 A 68226, JP-A No. 09-272735, JP-A No. 09-302084, JP-A No. 09-302085 discloses a charge transport polymer material described in JP-A 09-328539 discloses the like.

  In addition to the binder resin, a polymer charge transport material having a charge transport function, for example, polycarbonate, polyester, polyurethane, polyether having an arylamine skeleton, benzidine skeleton, hydrazone skeleton, carbazole skeleton, stilbene skeleton, pyrazoline skeleton, etc. A polymer material such as polysiloxane or acrylic resin, a polymer material having a polysilane skeleton, or the like can be used. Specific examples include polysilylene polymers described in JP-A 63-285552, JP-A 05-19497, JP-A 05-70595, JP-A 10-73944, and the like.

  The charge generation layer may contain a low molecular charge transport material. As the low molecular charge transport material, both a hole transport material and an electron transport material are suitable.

  As the electron transporting material, an electron accepting material is preferable. For example, 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, diphenoquinone derivatives, and the like. These can be used individually by 1 type or in mixture of 2 or more types.

  Suitable examples of the hole transporting material include the electron donating materials shown below, for example, 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, bisstilbene derivatives , Enamine derivatives, and the like. These hole transport materials can be used alone or as a mixture of two or more.

  The method for forming the charge generation layer is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include 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, and the like are suitable. Can be formed satisfactorily.

  As a method of providing a charge generation layer by the casting method, for example, the inorganic or organic charge generation material, together with a binder resin as necessary, is dispersed by a ball mill, an attritor, a sand mill, a bead mill or the like using a solvent, The dispersion can be formed by appropriately diluting and applying. Examples of the solvent include tetrahydrofuran, dioxane, dioxolane, toluene, dichloromethane, monochlorobenzene, dichloroethane, cyclohexanone, cyclopentanone, anisole, xylene, methyl ethyl ketone, acetone, ethyl acetate, butyl acetate, and the like. In addition, a leveling agent such as dimethyl silicone oil or methylphenyl silicone oil can be added to the dispersion 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 preferably 0.01 to 5 μm, more preferably 0.05 to 2 μm.

  Next, regarding the charge transport layer, the charge transport layer is a layer having a charge transport function, and contains a charge transport material, a binder resin, and other components as necessary. The thickness of the charge transport layer is preferably 5 to 40 μm, and more preferably 10 to 30 μm.

  The cross-linked surface layer is formed on the surface portion of the charge transport layer. When the charge transport layer has a laminated structure, the charge transport layer dissolves or disperses the charge transport material having a charge transport function and the binder resin in an appropriate solvent. Then, this is formed by coating and drying on the charge generation layer. A coating liquid containing at least two kinds of antioxidants contained in the upper layer of the charge transport layer in an amount of 0.2 to 10% by mass based on the total mass of the radical polymerizable composition of the present invention and the crosslinked surface layer. The crosslinked surface layer is formed by coating and curing by external energy such as heat or light. The thickness of the crosslinked surface layer is preferably 1 to 20 μm, more preferably 2 to 10 μm. If the film thickness is less than 1 μm, the durability may vary due to film thickness unevenness. If the film thickness is greater than 20 μm, the charge transport layer may be thick and image reproducibility may be reduced due to charge diffusion. is there.

  As the charge transport material, the electron transport material, hole transport material and polymer charge transport material described in the charge generation layer can be used. As described above, the use of the polymer charge transport material can reduce the solubility of the lower layer when the crosslinked surface layer is applied, and is particularly useful.

  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. Coalescence, polyvinyl acetate, polyvinylidene chloride, 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 resin, A silicone resin, an epoxy resin, a melamine resin, a urethane resin, a phenol resin, an alkyd resin, etc. are mentioned, These may be used individually by 1 type and may use 2 or more types together.

  The amount of the charge transport material added is preferably 20 to 300 parts by weight, and more preferably 40 to 150 parts by weight with respect to 100 parts by weight of the binder resin. However, when a polymer charge transport material is used, it can be used alone or in combination with a binder resin. As the solvent used for coating the charge transport layer, the same solvent as the charge generation layer can be used, but a solvent that dissolves the charge transport material and the binder resin well is suitable. These solvents may be used alone or in combination of two or more. The charge transport layer can be formed by the same coating method as that for the charge generation layer.

  Moreover, a plasticizer and a leveling agent can be added to the charge transport layer as necessary. As said plasticizer, what is used as a plasticizer of resin generally used, such as dibutyl phthalate and dioctyl phthalate, can be used. The amount of the plasticizer used is suitably 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, and polymers or oligomers having a perfluoroalkyl group in the side chain. The amount of the leveling agent used is preferably about 0 to 1 part by mass with respect to 100 parts by mass of the binder resin.

<Single layer photosensitive layer>
The photosensitive layer having a single layer structure is a layer having a charge generation function and a charge transport function at the same time, and the crosslinked surface layer having the above-described charge transport structure is usefully provided by being provided on the single layer structure photosensitive layer.

  When the cross-linked surface layer is provided on the surface of the photosensitive layer having a single layer structure, the photosensitive layer dissolves or disperses a charge generating material having a charge generating function, a charge transporting material having a charge transporting function, and a binder resin in an appropriate solvent. This can be formed by coating and drying. Moreover, a plasticizer, a leveling agent, etc. can also be added as needed. As the charge generation material dispersion method, the charge generation material, the charge transport material, the plasticizer, and the leveling agent, those similar to those already described in the charge generation layer and the charge transport layer can be used. As the binder resin, the binder resin mentioned in the charge generation layer may be mixed and used in addition to the binder resin mentioned above in the charge transport layer. In addition, the above-described polymer charge transport materials can also be used, which is useful in that contamination of the lower photosensitive layer composition into the crosslinked surface layer can be reduced. The film thickness of the photosensitive layer is preferably 5 to 30 μm, more preferably 10 to 25 μm.

  When the cross-linked surface layer is provided on the surface of the photosensitive layer having a single layer structure, as described above, the coating solution containing the radical polymerizable composition of the present embodiment and the charge generating material is applied to the upper layer of the photosensitive layer. After drying, the resin is cured by heat or light external energy to form a crosslinked surface layer. At this time, the film thickness of the crosslinked surface layer is preferably 1 to 20 μm, and more preferably 2 to 10 μm. If the film thickness is less than 1 μm, the durability may vary due to film thickness unevenness.

  The charge generation material contained in the photosensitive layer having the single layer structure is preferably 1 to 30% by mass based on the total amount of the photosensitive layer. The content of the binder resin contained in the lower layer portion of the photosensitive layer in the photosensitive layer is preferably 20 to 80% by mass, and the charge transport material is added in an amount of 10 to 70 parts by mass with respect to 100 parts by mass of the binder resin. It is preferable to do.

<Underlayer>
In the electrostatic latent image carrier of this embodiment, an undercoat layer can be provided between the support and the photosensitive layer. The undercoat layer generally contains a resin as a main component, but these resins are resins having a high solvent resistance with respect to a general organic solvent in consideration of applying a photosensitive layer thereon with a solvent. It is preferable. 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, melamine resin, phenol resin, alkyd-melamine resin, and epoxy. Examples thereof include a curable resin that forms a three-dimensional network structure such as a resin. In order to prevent moire and reduce residual potential, the undercoat layer is added with a fine powder pigment of a metal oxide such as titanium oxide, silica, alumina, zirconium oxide, tin oxide, or indium oxide. be able to.

For the undercoat layer, an anodized layer of Al ₂ O ₃ , an organic material such as polyparaxylylene (parylene), or an inorganic material such as SiO ₂ , SnO ₂ , TiO ₂ , ITO, or CeO ₂ is vacuumed. Those provided by the thin film preparation method can also be used favorably. In addition, known ones can be used. The undercoat layer can be formed using an appropriate solvent and a coating method like the photosensitive layer. Furthermore, a silane coupling agent, a titanium coupling agent, a chromium coupling agent, etc. can also be used as the undercoat layer of this embodiment. The undercoat layer may have a laminated structure of two or more layers, and the thickness of the undercoat layer is not particularly limited and can be appropriately selected according to the purpose, and is preferably 0 to 5 μm.

  In the electrostatic latent image carrier of the present embodiment, in order to improve environmental resistance, in order to prevent a decrease in sensitivity and an increase in residual potential, a charge generation layer, a charge transport layer, an undercoat layer, etc. It is possible to add the above-mentioned antioxidant to each of the layers, and 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.

-Synthesis of compounds having a functional charge transport structure-
The compound having a monofunctional charge transport structure in the present embodiment can be synthesized, for example, by the method described in Japanese Patent No. 3164426. An example of this is shown below.

(1) Synthesis of hydroxy group-substituted triarylamine compound (see the following chemical formula (181)) 113.85 g (0.3 mol) of methoxy group-substituted triarylamine compound (see the following chemical formula (180)) 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 the mixture was stirred at a temperature of about 60 ° C. for 4 and a half hours to complete the reaction. About 1.5 L of toluene was added to the reaction solution, cooled to room temperature, and washed repeatedly with water and an aqueous sodium carbonate solution. Thereafter, the solvent was removed from the toluene solution and purified by column chromatography (adsorption medium: silica gel, developing solvent: toluene: ethyl acetate = 20: 1). Cyclohexane was added to the obtained pale yellow oil to precipitate crystals. In this way, 88.1 g (yield = 80.4%) of white crystals of the following chemical formula (181) was obtained. The melting point is 64.0-66.0 ° C. In addition, as a result of measuring the content ratio of C, H, and N for the white crystal, as shown in Table 26 below, the content ratio (calculated value) of the following chemical formula (180) almost coincides with that of the chemical formula (181) It was confirmed that.

(2) Triarylamino group-substituted acrylate compound (see Exemplified Compound No. 71)
82.9 g (0.227 mol) of the hydroxy group-substituted triarylamine compound (chemical formula (181)) obtained in (1) above was dissolved in 400 ml of tetrahydrofuran, and an aqueous sodium hydroxide solution (NaOH: 12.4 g) in a nitrogen stream. , Water: 100 ml) was added dropwise. The solution was cooled to 5 ° C., and 25.2 g (0.272 mol) of acrylic acid chloride was added dropwise over 40 minutes. Then, it stirred at 5 degreeC for 3 hours, and complete | finished reaction. The reaction solution was poured into water and extracted with toluene. This extract was repeatedly washed with an aqueous sodium bicarbonate solution and water. Thereafter, the solvent was removed from the toluene solution and purified by column chromatography (adsorption medium: silica gel, developing solvent: toluene). N-Hexane was added to the obtained colorless oil to precipitate crystals. Thus, Exemplified Compound No. This gave 80.73 g (yield = 84.8%) of 71 white crystals. The melting point is 117.5-119.0 ° C. In addition, as a result of measuring the content ratio of C, H, and N about the said white crystal, as shown in the following Table 27, exemplary compound No. 71 almost coincides with the content ratio (calculated value) of No. 71. 71 was confirmed.

-Synthesis of compounds having a functional charge transport structure-
The compound dihydroxymethyltriphenylamine having a bifunctional charge transport structure in the present embodiment can be produced by the following method. First, 49 g of compound (1) represented by the following reaction formula and 184 g of phosphorus oxychloride were placed in a flask equipped with a thermometer, a condenser, a stirrer, and a dropping funnel, and dissolved by heating. 117 g of dimethylformamide was gradually dropped from the dropping funnel, and then the reaction solution temperature was kept at 85 to 95 ° C., and the mixture was stirred for about 15 hours. Next, the reaction solution was gradually poured into a large excess of warm water, and then slowly cooled with stirring. Next, the precipitated crystals were filtered and dried, and then purified by silica gel or the like by impurity adsorption and recrystallization with acetonitrile to obtain compound (2). Yield was 30 g. Then, 30 g of the obtained compound (2) and 100 ml of ethanol were put into a flask and stirred. After gradually adding 1.9 g of sodium borohydride, the liquid temperature was kept at 40 to 60 ° C., and the mixture was stirred for about 2 hours. Next, the reaction solution was gradually poured into about 300 ml of water and stirred to precipitate crystals. After filtration, the product was sufficiently washed with water and dried to obtain a compound (3) according to the reaction formula shown below. Yield was 30 g.

(Image forming method and image forming apparatus)
An image forming apparatus according to an embodiment of the present invention includes at least an electrostatic latent image carrier, an electrostatic latent image forming unit, a developing unit, a transfer unit, a fixing unit, and a cleaning unit. Other means appropriately selected as necessary, for example, static elimination means, recycling means, control means, and the like are provided.

  In addition, the image forming method in the embodiment of the present invention includes at least an electrostatic latent image forming step, a developing step, a transfer step, a fixing step, and a cleaning step, and the other selected as necessary. The process includes, for example, a static elimination process, a recycling process, a control process, and the like.

  The image forming method of the present embodiment can be preferably performed by the image forming apparatus, the electrostatic latent image forming step can be performed by the electrostatic latent image forming unit, and the developing step is performed by the developing unit. 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 electrostatic latent image carrier. The material, shape, structure, size, etc. of the electrostatic latent image carrier are not particularly limited, and can be appropriately selected from known ones. The shape is preferably a drum shape. It is done. As the electrostatic latent image carrier, the electrostatic latent image carrier of the present invention can be used.

  The electrostatic latent image bearing member (electrophotographic photosensitive member) of the present embodiment can be applied to general electrophotographic apparatuses such as copying machines, laser printers, LED printers, liquid crystal shutter printers, and the like. It can also be widely applied to devices such as displays, recording, light printing, plate making, facsimiles, etc., to which is applied.

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

  The charging can be performed, for example, by applying a voltage to the surface of the electrostatic latent image carrier 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 utilizing corona discharge such as corotrons and corotrons.

  The exposure can be performed, for example, by exposing the surface of the latent electrostatic image bearing member imagewise using the exposure device. The exposure device is not particularly limited as long as it can expose the surface of the electrostatic latent image carrier charged by the charger so as to form an image to be formed, and is appropriately selected according to the purpose. For example, 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, a back light system in which imagewise exposure is performed from the back side of the electrostatic latent image carrier may be employed. In addition, when the image forming apparatus is used as a copying machine or a printer, image exposure is performed by irradiating a photosensitive member with reflected light or transmitted light from a document, or by reading a document with a sensor and converting the laser into a signal. This is performed by irradiating light to the photosensitive member by scanning the beam, driving the LED array, or driving the liquid crystal shutter array.

<Development process and development means>
The developing step is a step of developing the electrostatic latent image using a toner or a developer to form a visible image. The visible image can be formed, for example, by developing the electrostatic latent image using a toner or a developer, and can be performed by the developing unit. The developing means is not particularly limited as long as it can be developed using, for example, toner or developer, and can be appropriately selected from known ones. Preferable examples include at least a developing unit capable of applying toner or developer to the electrostatic latent image in contact or non-contact. For the developing device, a dry development system is usually used. Further, it may be a single color developing device or a multicolor developing device, and has, for example, a stirrer for charging the toner or developer by frictional stirring and a rotatable magnet roller. And the like.

  In the developing device, for example, the toner and the carrier are mixed and stirred, and the toner is charged by friction at that time, and held on the surface of the rotating magnet roller in a raised state, thereby forming a magnetic brush. Since the magnet roller is arranged in the vicinity of the electrostatic latent image carrier, a part of the toner constituting the magnetic brush formed on the surface of the magnet roller is electrostatically attracted by the electrostatic force. Move to the surface of the latent image carrier. As a result, the electrostatic latent image is developed with toner, and a visible image is formed on the surface of the electrostatic latent image carrier. The developer accommodated in the developing device is a developer containing toner, but the developer may be a one-component developer or a two-component developer. As the toner, a commonly used toner can be used.

<Transfer process and transfer means>
The transfer step is a step of transferring the visible image to a recording medium. An intermediate transfer member is used, and after the visible image is primarily transferred onto the intermediate transfer member, the visible image is transferred to the recording medium. A secondary transfer mode is preferable, and a primary transfer step of forming a composite transfer image by transferring a visible image onto an intermediate transfer body using two or more colors, preferably a full color toner, as the toner, A mode including a secondary transfer step of transferring the composite transfer image onto the recording medium is more preferable. The transfer can be visualized by, for example, charging the latent electrostatic image bearing 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 transfer member 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 transfer member is not particularly limited and may be appropriately selected from known transfer members according to the purpose. For example, a transfer belt and the like are preferable.

  The transfer unit (the primary transfer unit and the secondary transfer unit) includes at least a transfer unit that peels and charges the visible image formed on the electrostatic latent image carrier to the recording medium side. Is preferred. 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.

<Fixing process and fixing means>
The fixing step is a step of fixing the visible image transferred to the recording medium by a fixing device, and may be performed each time the toner of each color is transferred to the recording medium, or may be performed on the toner of each color. You may carry out simultaneously in the state which laminated | stacked. 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 pressing roller, a combination of a heating roller, a pressing roller, and an endless belt. The heating in the heating and pressing means is usually preferably 80 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.

<Cleaning process and cleaning means>
The cleaning step is a cleaning step of cleaning the electrostatic latent image carrier using a cleaning unit. Examples of the cleaning means include a cleaning blade, a magnetic brush cleaner, an electrostatic brush cleaner, a magnetic roller cleaner, a blade cleaner, a brush cleaner, and a web cleaner. Examples of the material of the rubber blade used in the blade cleaning method include urethane rubber, silicone rubber, fluorine rubber, chloroprene rubber, butadiene rubber, and the like. Among these, urethane rubber is particularly preferable.

  By simultaneously controlling the hardness and the rebound resilience of the rubber blade, the reversal of the blade can be effectively suppressed. The JISA hardness at 25 ± 5 ° C. of the rubber blade is preferably 65-80. When the JISA hardness is less than 65, the blade may be easily reversed, and when it exceeds 80, the cleaning performance may be deteriorated. The rebound resilience of the rubber blade is preferably 20 to 75%. If the rebound resilience exceeds 75%, the blade may be easily reversed, and if it is less than 20%, the cleaning performance may deteriorate. Here, both the JISA hardness and the rebound resilience can be measured based on the vulcanized rubber physical test method of JIS K6301.

  The neutralization step is a step of performing neutralization by applying a neutralization bias to the electrostatic latent image carrier, 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 electrostatic latent image carrier. Preferably mentioned.

  The recycling step is a step of recycling the electrophotographic color toner removed in 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 it can control the movement of each means, and can be appropriately selected according to the purpose. Examples thereof include devices such as a sequencer and a computer.

  Here, an image forming apparatus according to an embodiment of the present invention will be described with reference to FIG. FIG. 3 is a schematic diagram for explaining the image forming apparatus according to the present embodiment, and a modified example shown later also belongs to the category of the present invention.

  A photoreceptor (hereinafter simply referred to as a photoreceptor) 201 as an electrostatic latent image carrier has a support, at least a crosslinked surface layer, and a photosensitive layer on the support. A photosensitive layer including a charge generation layer, a charge transport layer, and a crosslinked surface layer in this order. Although the photoconductor 201 has a drum shape, it may have a sheet shape or an endless belt shape.

  As the charger 203, a wire-type charger or a roller-shaped charger is used. As this charger, a corotron device, a scorotron device, a solid discharge element, a needle electrode device, a roller charging device, a conductive brush device or the like is preferably used. This charger charges the photoconductor, but dot reproducibility improves as the electric field strength applied to the photoconductor increases.

  For the image exposure unit 205, a light source capable of ensuring high luminance and writing with high resolution (600 dpi or higher resolution) such as a light emitting diode (LED), a semiconductor laser (LD), or electroluminescence (EL) is used. . Various types of filters such as a sharp cut filter, a band pass filter, a near infrared cut filter, a dichroic filter, an interference filter, and a color temperature conversion filter can be used to irradiate only light in a desired wavelength range.

  As the transfer means, a known transfer device can be used, but a combination of the transfer charger 210 and the separation charger 211 is effective as shown in FIG. In addition, a transfer belt and a transfer roller can be used, and it is desirable to use a contact type such as a transfer belt or a transfer roller that generates less ozone. As a voltage / current application method at the time of transfer, either a constant voltage method or a constant current method can be used, but the transfer charge amount can be kept constant, and a constant voltage with excellent stability can be used. The current method is more desirable.

  The developing member 206 has one developing sleeve, and the toner developed on the photosensitive member 201 is transferred to the transfer paper 209. Further, the toner image formed on the photoconductor is transferred onto the transfer paper to become an image on the transfer paper. At this time, there are two methods. One is a method of directly transferring the toner image developed on the surface of the photosensitive member as shown in FIG. 3 to the transfer paper, and the other is that the toner image is once transferred from the photosensitive member to the intermediate transfer member, and this is transferred to the transfer paper. It is the method of transferring to. Either case can be used in the present invention. As such a transfer member, a known member can be used as long as the structure of the present invention can be satisfied, and an electrostatic transfer method using a transfer charger and a bias roller, an adhesive transfer method, and a pressure transfer. A mechanical transfer method such as a method or a magnetic transfer method can be used. As the electrostatic transfer method, the charging means can be used. When positive (negative) charging is performed on the photosensitive member and image exposure is performed, a positive (negative) electrostatic latent image is formed on the surface of the photosensitive member. A positive image can be obtained by developing this with negative (positive) toner (electrodetection fine particles), and a negative image can be obtained by developing with positive (negative) toner.

  As a light source such as the static elimination lamp 202, all luminescent materials such as a fluorescent lamp, a tungsten lamp, a halogen lamp, a mercury lamp, a sodium lamp, a light emitting diode (LED), a semiconductor laser (LD), and an electroluminescence (EL) can be used. . Various types of filters such as a sharp cut filter, a band pass filter, a near infrared cut filter, a dichroic filter, an interference filter, and a color temperature conversion filter can be used to irradiate only light in a desired wavelength range. Such a light source or the like irradiates the photosensitive member with light by providing a transfer process, a static elimination process, a cleaning process, a pre-exposure process, and the like using light irradiation in addition to the process shown in FIG. This neutralization mechanism can be omitted when the AC component is superposed and used in the previous charging method, or when the residual potential of the photoreceptor is small. Further, instead of optical static elimination, an electrostatic static elimination mechanism (for example, a static elimination brush with a reverse bias applied or grounded) can be used. In FIG. 3, 208 is a registration roller, and 212 is a separation claw.

  In addition, the toner developed on the photoconductor 201 by the developing unit 206 is transferred to the transfer paper 209. When toner remaining on the photoconductor 201 is generated, the fur brush 214 and the blade 215 remove the toner from the photoconductor. Removed. Cleaning may be performed only with a cleaning brush, and a known brush such as a fur brush or a mag fur brush is used as the cleaning brush.

  Next, one aspect of carrying out the above-described image forming method by the image forming apparatus of the present embodiment will be described with reference to FIG. An image forming apparatus 100 shown in FIG. 4 includes a photosensitive drum 10 as the electrostatic latent image carrier (hereinafter, also referred to as “photosensitive member 10”), a charging roller 20 as the charging unit, An exposure device 30 as an exposure unit, a development device 40 as the development unit, an intermediate transfer member 50, a cleaning device 60 as the cleaning unit having a cleaning blade, and a static elimination lamp 70 as the static elimination unit. .

  The intermediate transfer member 50 is an endless belt, and is designed to be movable in the direction of an arrow by three rollers 51 that are arranged inside and stretched. Part of the three rollers 51 also functions as a transfer bias roller that can apply a predetermined transfer bias (primary transfer bias) to the intermediate transfer member 50. The intermediate transfer body 50 is provided with a cleaning device 90 having a cleaning blade in the vicinity thereof, and for transferring (secondary transfer) a developed image (toner image) onto a transfer sheet 95 as a final transfer material. A transfer roller 80 serving as a transfer unit to which a transfer bias can be applied is disposed to face the transfer roller 80. Around the intermediate transfer member 50, a corona charger 52 for applying a charge to the toner image on the intermediate transfer member 50 is arranged between the photosensitive member 10 and the intermediate transfer member 50 in the rotation direction of the intermediate transfer member 50. It is disposed between the contact portion and the contact portion between the intermediate transfer member 50 and the transfer paper 95.

  The developing device 40 includes a developing belt 41 as the developer carrying member, and a black developing unit 45K, a yellow developing unit 45Y, a magenta developing unit 45M, and a cyan developing unit 45C provided around the developing belt 41. . The black developing unit 45K includes a developer accommodating portion 42K, a developer supplying roller 43K, and a developing roller 44K. The yellow developing unit 45Y includes a developer accommodating portion 42Y, a developer supplying roller 43Y, and a developing roller 44Y. The magenta developing unit 45M includes a developer accommodating portion 42M, a developer supplying roller 43M, and a developing roller 44M, and the cyan developing unit 45C includes a developer accommodating portion 42C and a developer supplying roller 43C. And a developing roller 44C. The developing belt 41 is an endless belt, is rotatably stretched around a plurality of belt rollers, and a part thereof is in contact with the photoconductor 10.

  In the image forming apparatus 100 shown in FIG. 4, for example, the charging roller 20 charges the photosensitive drum 10 uniformly. The exposure device 30 performs imagewise exposure on the photosensitive drum 10 to form an electrostatic latent image. The electrostatic latent image formed on the photosensitive drum 10 is developed by supplying toner from the developing device 40 to form a visible image (toner image). The visible image (toner image) is transferred (primary transfer) onto the intermediate transfer member 50 by the voltage applied from the roller 51, and further transferred (secondary transfer) onto the transfer paper 95. As a result, a transfer image is formed on the transfer paper 95. The residual toner on the photoconductor 10 is removed by the cleaning device 60, and the charge on the photoconductor 10 is once removed by the charge eliminating lamp 70.

  Another aspect in which the above-described image forming method is performed by the image forming apparatus of the present embodiment will be described with reference to FIG. The image forming apparatus 100 shown in FIG. 5 does not include the developing belt 41 in the image forming apparatus 100 shown in FIG. 4, and a black developing unit 45K, a yellow developing unit 45Y, and a magenta developing unit 45M are provided around the photosensitive member 10. The cyan developing unit 45C has the same configuration as that of the image forming apparatus 100 shown in FIG. In FIG. 5, the same components as those in FIG. 4 are denoted by the same reference numerals.

  Another aspect in which the above-described image forming method is performed by the image forming apparatus of the present embodiment will be described with reference to FIG. The tandem image forming apparatus shown in FIG. 6 is a tandem type color image forming apparatus. The tandem 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. 6. An intermediate transfer body cleaning device 17 for removing residual toner on the intermediate transfer body 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 transfer paper 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. In the tandem image forming apparatus, a sheet reversing device 28 for reversing the transfer paper for image formation on both sides of the transfer paper is disposed in the vicinity of the secondary transfer device 22 and the fixing device 25. Yes.

  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 a 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 emitted from the first traveling body 33, and reflected light from the document surface is reflected by a mirror in the second traveling body 34 and received by the reading sensor 36 through the imaging lens 35. A color original (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 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. ) And black, yellow, magenta and cyan toner images are formed in the respective image forming means. 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 is respectively photosensitive as shown in FIG. A photosensitive member 10 for black (a photosensitive member for black 10K, a photosensitive member for yellow 10Y, a photosensitive member for magenta 10M and a photosensitive member for cyan 10C), a charger 60 for uniformly charging the photosensitive member 10, and each color image information. An exposure unit (not shown) that exposes the photoreceptor to each color image corresponding image (L in FIG. 7) and forms an electrostatic latent image corresponding to each color image on the photoreceptor 10; 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 charger 62 for transferring the toner image onto the intermediate transfer member 50, a photoconductor cleaning device 63, and a static eliminator 64 are provided, and each monochrome image (black) is based on the image information of each color. Image, 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 manner are respectively transferred to the black photoconductor on the intermediate transfer member 50 that is rotationally moved by the support rollers 14, 15 and 16 (see FIG. 6). A black image formed on 10K, a yellow image formed on the yellow photoconductor 10Y, a magenta image formed on the magenta photoconductor 10M, and a cyan image formed on the cyan photoconductor 10C are sequentially formed. 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 sheet P (recording paper) from one of the paper feed cassettes 144 provided in multiple stages in the paper bank 143, and the separation roller 145. The sheet is separated one by one and sent to the sheet feeding path 146, conveyed by the conveying roller 147, guided to the sheet feeding path 148 in the copying machine main body 150, and abutted against the registration roller 49 and stopped. Alternatively, the sheet feeding roller 150 is rotated to feed out the sheets (recording paper) on the manual feed tray 51, 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 a synthesized color image (color transfer image) synthesized on the intermediate transfer member 50, and a sheet (recording paper) is interposed between the intermediate transfer member 50 and the secondary transfer device 22. The secondary color transfer device 22 transfers the composite color image (color transfer image) onto the sheet (recording paper) (secondary transfer), thereby transferring the color image onto the sheet (recording paper). Is formed. The residual toner on the intermediate transfer member 50 after image transfer is cleaned by the intermediate transfer member cleaning device 17.

  The sheet P (recording paper) on which the color image has been transferred is transported by the secondary transfer device 22 and sent to the fixing device 25, where the composite color image ( A color transfer image) is fixed on the sheet (recording paper). Thereafter, the sheet (recording paper) is switched by the switching claw 55 and discharged by the discharge roller 56 and stacked on the discharge tray 57, or switched by the switching claw 55 and reversed by the sheet reversing device 28 and transferred again. After being guided to the position and recording an image on the back surface, the image is discharged by the discharge roller 56 and stacked on the discharge tray 57.

  In the image forming apparatus and the image forming method of the present embodiment, a reaction product of a trifunctional or higher functional radical polymerizable compound having no charge transport structure and a monofunctional radical polymerizable compound having a charge transport structure, and a specific By using an electrostatic latent image carrier having a crosslinked surface layer containing a compound of the structural formula and having a small amount of wear, a high-definition and high-quality image can be formed over a long period of time.

  The process cartridge according to the embodiment of the present invention develops an electrostatic latent image carrier that carries an electrostatic latent image and the electrostatic latent image carried on the electrostatic latent image carrier using a developer. And at least developing means for forming a visible image, and other means appropriately selected as necessary.

  The electrostatic latent image carrier has a support, and at least a cross-linked surface layer and a photosensitive layer on the support, and the cross-linked surface layer does not have a charge transporting structure. Including a reaction product of a monofunctional radically polymerizable compound having a charge transporting structure and a specific structural formula, and the same as described above.

  The developing means includes at least a developer container that contains toner or developer, and a developer carrier that carries and transports the toner or developer contained in the developer container. In addition, a layer thickness regulating member for regulating the thickness of the toner layer to be carried may be provided. The process cartridge of this embodiment can be detachably provided in various image forming apparatuses, and is preferably provided detachably in the above-described image forming apparatus.

  Here, as the process cartridge, for example, as shown in FIG. 8, a photosensitive member 101 is incorporated, and in addition, a charging unit 102, a developing unit 104, and a cleaning unit 107 are included. Have. The photoreceptor 101 has a support, and at least a crosslinked surface layer and a photosensitive layer on the support. For example, a known charging member is used as the charging unit 102. As the exposure unit 103, for example, a light source capable of writing with high resolution is used.

  The image forming apparatus of the present embodiment is configured by integrally combining the above-described electrostatic latent image carrier and components such as a developing device and a cleaning device as a process cartridge, and this unit is attached to and detached from the apparatus main body. You may comprise freely. Further, at least one of a charging device, an image exposure device, a developing device, a transfer or separation device, and a cleaning device is integrally supported together with a photosensitive member to form a process cartridge, and is detachably attached to the image forming apparatus body. In addition, it may be configured to be detachable using guide means such as a rail of the apparatus main body.

  Examples of the present invention will be described below, but the present invention is not limited to these examples. In the following examples, “part” represents “part by mass”.

[Example 1]
The undercoat layer coating solution having the following composition was applied to an aluminum support (outer diameter 30 mm) by a dipping method so that the film thickness after drying was 3.5 μm to form an undercoat layer.

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

  Next, dip coating was performed on the undercoat layer with a charge generation layer coating solution having the following composition, followed by drying by heating to form a charge generation layer having a thickness of 0.2 μm.

<Composition of coating solution for charge generation layer>
-Bisazo pigment represented by the following chemical formula (182) 2.5 parts-Polyvinyl butyral (XYHL, manufactured by UCC) 0.5 part-Cyclohexanone 200 parts-Methyl ethyl ketone 80 parts

  Next, dip coating was performed on the charge generation layer using a charge transport layer coating solution having the following composition, followed by drying by heating to form a charge transport layer having a thickness of 22 μm.

<Composition of coating solution for charge transport layer>
10 parts of bisphenol Z-type polycarbonate 10 parts of low-molecular charge transport material represented by the following chemical formula (183) 80 parts of tetrahydrofuran Tetrahydrofuran solution of 1% by weight silicone oil (KF50, manufactured by Shin-Etsu Chemical Co., Ltd.) 0.2 Part

  Next, spray coating is performed on the charge transport layer using the coating liquid for the crosslinked surface layer having the following constitution, and then light irradiation is performed under the conditions of a metal halide lamp, irradiation light intensity: 450 mW / cm2, and irradiation time: 120 seconds. Went. Further, drying was performed at 130 ° C. for 30 minutes to form a crosslinked surface layer having a thickness of 4.0 μm. Thus, an electrostatic latent image carrier was produced.

<Composition of coating solution for cross-linked surface layer>
・ Trifunctional or higher radical polymerizable monomer 1 having no charge transport structure (KAYARAD TMPTA, manufactured by Nippon Kayaku Co., Ltd.) 8 parts ・ Trifunctional or higher radical polymerizable monomer 2 having no charge transport structure ( KAYARAD DPCA120, manufactured by Nippon Kayaku Co., Ltd.) 2 parts monofunctional radical polymerizable compound having a charge transporting structure (Exemplary Compound No. 71)
1 part 1-hydroxy-cyclohexyl-phenyl-ketone (Irgacure 184, manufactured by Ciba Specialty Chemicals) 1 part tetrahydrofuran 80 parts 2,9-dimethyl-4,7-diphenyl-1 , 10-phenanthroline (manufactured by Tokyo Chemical Industry Co., Ltd.) (see chemical formula (7) below) 0.5 part

[Example 2]
In Example 1, a latent electrostatic image bearing member was produced in the same manner as in Example 1 except that the crosslinked surface layer coating solution of Example 1 was changed to the following composition.

<Composition of coating solution for cross-linked surface layer>
・ Trifunctional or higher radical polymerizable monomer 1 having no charge transport structure (KAYARAD TMPTA, manufactured by Nippon Kayaku Co., Ltd.) 8 parts ・ Trifunctional or higher radical polymerizable monomer 2 having no charge transport structure ( KAYARAD DPCA120, manufactured by Nippon Kayaku Co., Ltd.) 2 parts: a monofunctional radically polymerizable compound having a charge transporting structure (Exemplary Compound No. 73)
10 parts 1-Hydroxy-cyclohexyl-phenyl-ketone (Irgacure 184, manufactured by Ciba Specialty Chemicals) 1 part Tetrahydrofuran 80 parts 2- (4-t-butylphenyl) -5 (4-Biphenylyl) -1,3,4-oxadiazole (manufactured by Tokyo Chemical Industry Co., Ltd.) (see the following chemical formula (8)) 0.5 part

[Example 3]
In Example 1, a latent electrostatic image bearing member was produced in the same manner as in Example 1 except that the crosslinked surface layer coating solution of Example 1 was changed to the following composition.

<Composition of coating solution for cross-linked surface layer>
・ Trifunctional or higher radical polymerizable monomer 1 having no charge transport structure (KAYARAD TMPTA, manufactured by Nippon Kayaku Co., Ltd.) 8 parts ・ Trifunctional or higher radical polymerizable monomer 2 having no charge transport structure ( KAYARAD DPCA120, manufactured by Nippon Kayaku Co., Ltd.) 2 parts monofunctional radical polymerizable compound having a charge transporting structure (Exemplary Compound No. 75)
10 parts 1-hydroxy-cyclohexyl-phenyl-ketone (Irgacure 184, manufactured by Ciba Specialty Chemicals) as a photopolymerization initiator 1 part Tetrahydrofuran 80 parts 3- (4-t-butylphenyl) -4- Phenyl-5- (4-biphenylyl) -1,2,4-triazole (manufactured by Ricoh) (see the following chemical formula (9)) 0.5 part

[Example 4]
In Example 1, a latent electrostatic image bearing member was produced in the same manner as in Example 1 except that the crosslinked surface layer coating solution of Example 1 was changed to the following composition.

<Composition of coating solution for cross-linked surface layer>
・ Trifunctional or higher radical polymerizable monomer 1 having no charge transport structure (KAYARAD TMPTA, manufactured by Nippon Kayaku Co., Ltd.) 8 parts ・ Trifunctional or higher radical polymerizable monomer 2 having no charge transport structure ( KAYARAD DPCA120, manufactured by Nippon Kayaku Co., Ltd.) 2 parts: a monofunctional radically polymerizable compound having a charge transporting structure (Exemplary Compound No. 77)
1 part 1-hydroxy-cyclohexyl-phenyl-ketone (Irgacure 184, manufactured by Ciba Specialty Chemicals) 1 part tetrahydrofuran 80 parts bis (2-methyl-8-quinolinolato) (p-phenylphenol) Lato) Aluminum (manufactured by Tokyo Chemical Industry Co., Ltd.) (see chemical formula (10) below) 0.5 parts

[Example 5]
In Example 1, a latent electrostatic image bearing member was produced in the same manner as in Example 1 except that the crosslinked surface layer coating solution of Example 1 was changed to the following composition.

<Composition of coating solution for cross-linked surface layer>
・ Trifunctional or higher radical polymerizable monomer 1 having no charge transport structure (KAYARAD TMPTA, manufactured by Nippon Kayaku Co., Ltd.) 8 parts ・ Trifunctional or higher radical polymerizable monomer 2 having no charge transport structure ( KAYARAD DPHA, manufactured by Nippon Kayaku Co., Ltd.) 2 parts monofunctional radical polymerizable compound having a charge transporting structure (Exemplary Compound No. 71)
1 part 1-hydroxy-cyclohexyl-phenyl-ketone (Irgacure 184, manufactured by Ciba Specialty Chemicals) 1 part tetrahydrofuran 80 parts 2,9-dimethyl-4,7-diphenyl-1 , 10-phenanthroline (manufactured by Tokyo Chemical Industry Co., Ltd.) (see the above chemical formula (7)) 0.5 part 2- (4-t-butylphenyl) -5- (4-biphenylyl) -1,3,4-oxa Diazole (manufactured by Tokyo Chemical Industry Co., Ltd.) (see chemical formula (8) above) 0.5 part

[Example 6]
In Example 1, a latent electrostatic image bearing member was produced in the same manner as in Example 1 except that the crosslinked surface layer coating solution of Example 1 was changed to the following composition.

<Composition of coating solution for cross-linked surface layer>
・ Trifunctional or higher radical polymerizable monomer 1 having no charge transport structure (KAYARAD TMPTA, manufactured by Nippon Kayaku Co., Ltd.) 8 parts ・ Trifunctional or higher radical polymerizable monomer 2 having no charge transport structure ( KAYARAD DPHA, manufactured by Nippon Kayaku Co., Ltd.) 2 parts monofunctional radical polymerizable compound having a charge transporting structure (Exemplary Compound No. 73)
1 part 1-hydroxy-cyclohexyl-phenyl-ketone (Irgacure 184, manufactured by Ciba Specialty Chemicals) 1 part tetrahydrofuran 80 parts 3- (4-t-butylphenyl) -4-phenyl- 5- (4-biphenylyl) -1,2,4-triazole (manufactured by Ricoh) (see the above chemical formula (9)) 0.5 parts bis (2-methyl-8-quinolinolato) (p-phenylphenolato) aluminum (Tokyo Kasei) (Manufactured by Kogyo Co., Ltd.) (see chemical formula (10) above) 0.5 parts

[Example 7]
In Example 1, a latent electrostatic image bearing member was produced in the same manner as in Example 1 except that the crosslinked surface layer coating solution of Example 1 was changed to the following composition.

<Composition of coating solution for cross-linked surface layer>
・ Trifunctional or higher radical polymerizable monomer 1 having no charge transport structure (KAYARAD TMPTA, manufactured by Nippon Kayaku Co., Ltd.) 8 parts ・ Trifunctional or higher radical polymerizable monomer 2 having no charge transport structure ( KAYARAD DPCA120, manufactured by Nippon Kayaku Co., Ltd.) 2 parts monofunctional radical polymerizable compound having a charge transporting structure (Exemplary Compound No. 71)
1 part 1-hydroxy-cyclohexyl-phenyl-ketone (Irgacure 184, manufactured by Ciba Specialty Chemicals) 1 part tetrahydrofuran 80 parts 2,9-dimethyl-4,7-diphenyl-1 , 10-phenanthroline (manufactured by Tokyo Chemical Industry Co., Ltd.) (see chemical formula (7) above) 0.2 part

[Example 8]
In Example 1, a latent electrostatic image bearing member was produced in the same manner as in Example 1 except that the crosslinked surface layer coating solution of Example 1 was changed to the following composition.

<Composition of coating solution for cross-linked surface layer>
・ Trifunctional or higher radical polymerizable monomer 1 having no charge transport structure (KAYARAD TMPTA, manufactured by Nippon Kayaku Co., Ltd.) 8 parts ・ Trifunctional or higher radical polymerizable monomer 2 having no charge transport structure ( KAYARAD DPCA120, manufactured by Nippon Kayaku Co., Ltd.) 2 parts monofunctional radical polymerizable compound having a charge transporting structure (Exemplary Compound No. 71)
1 part 1-hydroxy-cyclohexyl-phenyl-ketone (Irgacure 184, manufactured by Ciba Specialty Chemicals) 1 part tetrahydrofuran 80 parts 2,9-dimethyl-4,7-diphenyl-1 , 10-phenanthroline (manufactured by Tokyo Chemical Industry Co., Ltd.) (see chemical formula (7) above) 10 parts

[Comparative Example 1]
In Example 1, an electrostatic latent image bearing member was produced in the same manner as in Example 1 except that the coating solution for the crosslinked surface layer was changed to the following composition.

<Composition of coating solution for cross-linked surface layer>
・ Trifunctional or higher radical polymerizable monomer 1 having no charge transport structure (KAYARAD TMPTA, manufactured by Nippon Kayaku Co., Ltd.) 8 parts ・ Trifunctional or higher radical polymerizable monomer 2 having no charge transport structure ( KAYARAD DPCA120, manufactured by Nippon Kayaku Co., Ltd.) 2 parts monofunctional radical polymerizable compound having a charge transporting structure (Exemplary Compound No. 71)
10 parts 1-hydroxy-cyclohexyl-phenyl-ketone (Irgacure 184, manufactured by Ciba Specialty Chemicals) as a photopolymerization initiator 1 part 80 parts tetrahydrofuran

[Comparative Example 2]
In Example 1, an electrostatic latent image bearing member was produced in the same manner as in Example 1 except that the coating solution for the crosslinked surface layer was changed to the following composition.

<Composition of coating solution for cross-linked surface layer>
・ Trifunctional or higher radical polymerizable monomer 1 having no charge transport structure (KAYARAD TMPTA, manufactured by Nippon Kayaku Co., Ltd.) 8 parts ・ Trifunctional or higher radical polymerizable monomer 2 having no charge transport structure ( KAYARAD DPCA120, manufactured by Nippon Kayaku Co., Ltd. 2 parts: 10 parts of a charge transporting compound of the following chemical formula (184) having no functional group: 1-hydroxy-cyclohexyl-phenyl-ketone (Irgacure as a photopolymerization initiator) 184, manufactured by Ciba Specialty Chemicals Co., Ltd.) 1 part tetrahydrofuran 80 parts 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (manufactured by Tokyo Chemical Industry Co., Ltd.) (see chemical formula (7) above) 0.5 part

[Comparative Example 3]
In Example 1, an electrostatic latent image bearing member was produced in the same manner as in Example 1 except that the coating solution for the crosslinked surface layer was changed to the following composition.

<Composition of coating solution for cross-linked surface layer>
・ Trifunctional or higher radical polymerizable monomer 1 having no charge transport structure (KAYARAD TMPTA, manufactured by Nippon Kayaku Co., Ltd.) 8 parts ・ Trifunctional or higher radical polymerizable monomer 2 having no charge transport structure ( KAYARAD DPCA120, manufactured by Nippon Kayaku Co., Ltd.) 2 parts bifunctional radically polymerizable compound having the following chemical formula (185) having a charge transporting structure
1 part 1-hydroxy-cyclohexyl-phenyl-ketone (Irgacure 184, manufactured by Ciba Specialty Chemicals) 1 part tetrahydrofuran 80 parts 2,9-dimethyl-4,7-diphenyl-1 , 10-phenanthroline (manufactured by Tokyo Chemical Industry Co., Ltd.) (see chemical formula (7) above) 0.5 part

[Comparative Example 4]
In Example 1, a latent electrostatic image bearing member was produced in the same manner as in Example 1, except that the coating solution for the crosslinked surface layer was changed to the following composition.

<Composition of coating solution for cross-linked surface layer>
10 parts of a bifunctional radically polymerizable monomer 1 having no charge transporting structure (ABE-300, manufactured by Shin-Nakamura Chemical Co., Ltd.) A monofunctional radically polymerizable compound having a charge transporting structure (Exemplary Compound No. 71) )
1 part 1-hydroxy-cyclohexyl-phenyl-ketone (Irgacure 184, manufactured by Ciba Specialty Chemicals) 1 part tetrahydrofuran 80 parts 2,9-dimethyl-4,7-diphenyl-1 , 10-phenanthroline (manufactured by Tokyo Chemical Industry Co., Ltd.) (see chemical formula (7) above) 0.5 part

[Comparative Example 5]
In Example 1, a latent electrostatic image bearing member was produced in the same manner as in Example 1, except that the coating solution for the crosslinked surface layer was changed to the following composition.

<Composition of coating solution for cross-linked surface layer>
・ Trifunctional or higher radical polymerizable monomer 1 having no charge transport structure (KAYARAD TMPTA, manufactured by Nippon Kayaku Co., Ltd.) 8 parts ・ Trifunctional or higher radical polymerizable monomer 2 having no charge transport structure ( KAYARAD DPCA120, manufactured by Nippon Kayaku Co., Ltd.) 2 parts monofunctional radical polymerizable compound having a charge transporting structure (Exemplary Compound No. 71)
1 part 1-hydroxy-cyclohexyl-phenyl-ketone (Irgacure 184, manufactured by Ciba Specialty Chemicals) 1 part tetrahydrofuran 80 parts 2,9-dimethyl-4,7-diphenyl-1 , 10-phenanthroline (manufactured by Tokyo Chemical Industry Co., Ltd.) (see chemical formula (7) above) 0.1 part

[Comparative Example 6]
In Example 1, a latent electrostatic image bearing member was produced in the same manner as in Example 1, except that the coating solution for the crosslinked surface layer was changed to the following composition.

<Composition of coating solution for cross-linked surface layer>
・ Trifunctional or higher radical polymerizable monomer 1 having no charge transport structure (KAYARAD TMPTA, manufactured by Nippon Kayaku Co., Ltd.) 8 parts ・ Trifunctional or higher radical polymerizable monomer 2 having no charge transport structure ( KAYARAD DPCA120, manufactured by Nippon Kayaku Co., Ltd.) 2 parts monofunctional radical polymerizable compound having a charge transporting structure (Exemplary Compound No. 71)
1 part 1-hydroxy-cyclohexyl-phenyl-ketone (Irgacure 184, manufactured by Ciba Specialty Chemicals) 1 part tetrahydrofuran 80 parts 2,9-dimethyl-4,7-diphenyl-1 , 10-phenanthroline (manufactured by Tokyo Chemical Industry Co., Ltd.) (see chemical formula (7) above) 12 parts

[Comparative Example 7]
In Example 1, an electrostatic latent image carrier was produced in the same manner as in Example 1 except that the crosslinked surface layer was not provided.

<Performance evaluation>
Each produced electrostatic latent image carrier (electrophotographic photosensitive member) is mounted on an image forming apparatus (manufactured by Ricoh Co., Ltd., imagio Neo270 modified machine, 655 nm semiconductor laser as an image exposure light source), and 100,000 actual machines A paper passing test (A4 size, manufactured by NBS Ricoh, MyPaper, charging potential at start-700 V) was performed, and the amount of wear, electrical characteristics, and image evaluation were performed as follows. The results are shown in Table 28, Table 29, and Table 30.

<Measurement of wear>
Using an eddy current film thickness meter (MMS, manufactured by Fischerscope), the film thickness before and after the actual paper passing test was measured, and the amount of wear (μm) was calculated from the difference in film thickness before and after.

<Evaluation of electrical characteristics>
The image forming apparatus (made by Ricoh Co., Ltd., imgio Neo 270 modified machine) was modified so that the surface potential meter could be installed. After passing 50,000 sheets and 100,000 sheets initially, dark area potential and light area potential were changed. It was measured.

<Image evaluation>
Using an image forming apparatus (made by Ricoh Co., Ltd., imagio Neo270 modified machine), after the initial 50,000 sheets and 100,000 sheets are passed, the image is output using the test chart (S-3), and the abnormal image The presence or absence was confirmed.

  In Comparative Example 7, the amount of wear was large, so that it was canceled after 50,000 sheets.

  Table 30 shows image characteristics (S-3 chart evaluation).

  From the results of Table 28 to Table 30, a reaction product of a trifunctional or higher functional radical polymerizable compound having no charge transport structure and a monofunctional radical polymerizable compound having a charge transport structure, and at least a specific structural formula. Examples 1 to 8 using an electrostatic latent image carrier having a crosslinked surface layer containing bismuth have higher scratch resistance and wear resistance and better electrical properties than Comparative Examples 1 to 7. It is recognized that high image quality can be realized over a long period of time.

  The electrostatic latent image carrier of the above-described embodiment has a photosensitive layer having high scratch resistance and abrasion resistance and good electrical characteristics, and can realize high image quality over a long period of time. In addition to being used in copying machines, it can be widely used in electrophotographic application fields such as laser beam printers, CRT printers, LED printers, liquid crystal printers, and laser plate making.

  In addition, an image forming method, an image forming apparatus, and a process cartridge using the electrostatic latent image carrier of the above-described embodiment are a full color copier, a full color laser printer, a direct or indirect electrophotographic multicolor image developing system, And it can be used widely for full-color plain paper fax.

  The above-described embodiment is a preferred embodiment of the present invention, and the scope of the present invention is not limited to the above-described embodiment alone, and various modifications are made without departing from the gist of the present invention. Implementation is possible.

It is the schematic sectional drawing which showed an example of the layer structure of the electrostatic latent image carrier (single layer type) which concerns on embodiment of this invention. It is the schematic sectional drawing which showed an example of the layer structure of the electrostatic latent image carrier (laminate type) which concerns on embodiment of this invention. 1 is a schematic configuration diagram illustrating an aspect of an image forming apparatus according to an embodiment of the present invention. 1 is a schematic configuration diagram illustrating an aspect of an image forming apparatus according to an embodiment of the present invention. 1 is a schematic configuration diagram illustrating an aspect of an image forming apparatus according to an embodiment of the present invention. 1 is a schematic configuration diagram illustrating an aspect of an image forming apparatus according to an embodiment of the present invention. 1 is a schematic configuration diagram illustrating an aspect of an image forming apparatus according to an embodiment of the present invention. 1 is a schematic configuration diagram of a process cartridge according to an embodiment of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Support body 2 Charge generation layer 3 Photosensitive layer 4 Crosslinked surface layer 5 Charge transport layer 10, 10K, 10Y, 10M, 10C Photoconductor 18 Image forming means 20 Charging roller 21 Exposure device 22 Secondary transfer device 24 Secondary transfer belt 25 Fixing device 30 Exposure device 40 Developing device 50 Intermediate transfer member 58 Corona charger 60 Cleaning device 61 Developing device 62 Transfer charger 63 Photoconductor cleaning device 64 Static eliminator 70 Static elimination lamp 71 Cleaning blade 72 Support member 80 Transfer roller 90 Cleaning device 95 Transfer paper 100 Image forming apparatus 101 Electrostatic latent image carrier (photosensitive member)
DESCRIPTION OF SYMBOLS 102 Charging means 103 Exposure 104 Developing means 105 Transfer body 107 Cleaning means 108 Transfer means

Claims (14)

  A support, and at least a crosslinked surface layer and a photosensitive layer on the support, the crosslinked surface layer having a trifunctional or higher functional radical polymerizable compound having no charge transporting structure and a charge transporting structure. Reaction product with monofunctional radically polymerizable compound and 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline and 2- (4-t-butylphenyl) -5- (4-biphenylyl) -1,3,4-oxadiazole and 3- (4-t-butylphenyl) -4-phenyl-5- (4-biphenylyl) -1,2,4-triazole and bis (2-methyl-8-quinolinolato And (p-phenylphenolato) at least one compound selected from aluminum.   The electrostatic latent image carrier according to claim 1, wherein the amount of the compound contained in the crosslinked surface layer is 0.2 to 10% by mass.   The electrostatic latent image according to claim 1 or 2, wherein a functional group of the tri- or higher functional radical polymerizable compound having no charge transporting structure is at least one of an acryloyloxy group and a methacryloyloxy group. Carrier.   The ratio of the molecular weight to the number of functional groups (molecular weight / number of functional groups) in the trifunctional or higher functional radical polymerizable compound not having the charge transporting structure is 250 or less. The electrostatic latent image carrier described in 1.   The static group according to any one of claims 1 to 4, wherein the functional group of the monofunctional radically polymerizable compound having the charge transporting structure is either an acryloyloxy group or a methacryloyloxy group. Electro-latent image carrier.   6. The electrostatic latent image carrying device according to claim 1, wherein the charge transporting structure of the monofunctional radically polymerizable compound having the charge transporting structure is a triarylamine structure. body. The monofunctional radically polymerizable compound having a charge transporting structure is at least one selected from compounds represented by the compounds represented by the following general formulas (1) and (2): The electrostatic latent image carrier according to any one of claims 1 to 6.

(In the general formulas (1) and (2), R1 may have a hydrogen atom, a halogen atom, a cyano group, a nitro group, an alkyl group which may have a substituent, or a substituent. A good aralkyl group, an aryl group which may have a substituent, an alkoxy group, —COOR ₇ (wherein R ₇ may have a hydrogen atom, an alkyl group which may have a substituent, or a substituent; A good aralkyl group or an aryl group which may have a substituent, a carbonyl halide group, and —CONR ₈ R ₉ (wherein R ₈ and R ₉ may be the same as or different from each other). Or 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. Ar ₁ and Ar ₂ may be the same as each other. And Ar ₃ and Ar ₄ may be the same as or different from each other and may have a substituent. X represents a single bond, an alkylene group which may have a substituent, a cycloalkylene group which may have a substituent, or an alkylene ether which may have a substituent. 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. M and n represent an integer of 0 to 3) 8. The electrostatic latent according to claim 1, wherein the monofunctional radically polymerizable compound having a charge transporting structure contains a compound represented by the following general formula (3): Image carrier.

(In the formula (3), o, p, and q each represent an integer of 0 or 1. Ra represents a hydrogen atom or a methyl group. Rb and Rc are the same as each other. Or may be different and each represents an alkyl group having 1 to 6 carbon atoms, s and t each represent an integer of 0 to 3. Za is a single bond, a methylene group, an ethylene group, or the following chemical formula ( 4) represents a substituent represented by (6).)

  The content of the trifunctional or higher functional radical polymerizable compound having no charge transporting structure in the crosslinked surface layer is 20 to 80% by mass. An electrostatic latent image carrier.   9. The electrostatic according to claim 1, wherein the content of the monofunctional radically polymerizable compound having the charge transporting structure in the crosslinked surface layer is 20 to 80% by mass. Latent image carrier. An electrostatic latent image forming step of forming an electrostatic latent image on the electrostatic latent image carrier, a developing step of developing the electrostatic latent image using toner to form a visible image, and the visible image In an image forming method including a transfer step of transferring the image to a recording medium and a fixing step of fixing the transferred image transferred to the recording medium,
The image forming method according to claim 1, wherein the electrostatic latent image carrier is the electrostatic latent image carrier according to claim 1. An electrostatic latent image carrier, an electrostatic latent image forming means for forming an electrostatic latent image on the electrostatic latent image carrier, and developing the electrostatic latent image with toner to form a visible image An image forming apparatus comprising: a developing unit that performs transfer; a transfer unit that transfers the visible image to a recording medium; and a fixing unit that fixes the transfer image transferred to the recording medium.
The image forming apparatus according to claim 1, wherein the electrostatic latent image carrier is the electrostatic latent image carrier according to claim 1.   13. The electrostatic latent image forming unit includes at least a charger that charges the surface of the electrostatic latent image carrier and an exposure unit that exposes the surface of the electrostatic latent image carrier. The image forming apparatus described.   An electrostatic latent image carrier, and electrostatic latent image forming means for forming an electrostatic latent image on the electrostatic latent image carrier, and further developing the electrostatic latent image with toner. At least one selected from a developing unit that forms a visual image, a transfer unit that transfers the visible image to a recording medium, and a cleaning unit that removes toner remaining on the electrostatic latent image carrier is an image forming apparatus. 11. A process cartridge comprising a main body detachably attached to the main body, wherein the electrostatic latent image carrier is the electrostatic latent image carrier according to claim 1.

Images