JP2007079505A - Electrophotographic photoreceptor, image forming apparatus, full-color image forming apparatus and process cartridge - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electrophotographic photoreceptor which ensures less variation in electrostatic properties and occurrence of few abnormal images in repetitive use of an image forming apparatus and under variation of the environment in which the image forming apparatus is set, and to provide the image forming apparatus and a full-color image forming apparatus capable of outputting always stable images and a process cartridge having high convenience of handling by using the electrophotographic photoreceptor. <P>SOLUTION: The electrophotographic photoreceptor has at least a photosensitive layer on a conductive support, wherein the conductive support surface has been subjected to anodic oxidation coating treatment, and the electrophotographic photoreceptor has an electron transport agent represented by formula (1) in the photosensitive layer. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an electrophotographic photosensitive member such as a laser printer, a copying machine, and a facsimile, a process cartridge for an image forming apparatus, an image forming apparatus, and a full-color image forming apparatus.

  In recent years, there has been a remarkable development of information processing system machines using electrophotography. In particular, an optical printer that converts information into a digital signal and records information by light is markedly improved in print quality and reliability. This digital recording technology is applied not only to printers but also to ordinary copying machines, and so-called digital copying machines have been developed. In addition, since a variety of information processing functions are added to a conventional copying machine in which this digital recording technology is mounted on an analog copying machine, it is expected that its demand will increase further in the future.

  In such digital copiers and digital printers, the image area ratio in the original is usually about 10% or less, so that writing is performed on the image portion in consideration of deterioration of the light source and light fatigue of the photoconductor. A reversal development (negative / positive development) method in which a toner image is developed in a portion where the potential is attenuated is the mainstream. This reversal development method requires a small amount of light irradiation to the photoconductor, and is an advantageous development method for the photoconductor in consideration of light fatigue in repeated use. However, there is a slight defect in the photoconductor, and potential leakage occurs. When such a phenomenon occurs, a point defect (background stain, black spot, etc.) occurs in the background portion (white background) that is not included in the document. This defect may be mistaken for a point in the drawing, a period in the English manuscript, a comma, or the like, and can be said to be a fatal defect as an image.

  Such defects are mostly due to local potential leakage of the photoconductor, and the main issues are improvement of the pressure resistance of the photoconductor, improvement of charging uniformity, and improvement of potential holding uniformity. It has become. In view of this point, attempts have been made to provide an intermediate layer (undercoat layer) between the conductive support and the photosensitive layer. The configuration of the intermediate layer is a layer in which a binder resin is a main component and a filler is dispersed as necessary.

  For example, in the case where the binder resin alone is configured as disclosed (for example, see Patent Documents 1 to 4), the binder resin is a material having high electrical insulation, so the intermediate layer is made very thin. In most cases, the configuration is 2 μm or less. In such a case, since the formation method is performed by a wet coating method, it is difficult to avoid pinholes in the coating film, and an expected effect cannot be obtained.

  Since most of the mainstream photoconductors are hole transport type photoconductors, the thickness of the intermediate layer has been increased by adding an electron conductive filler to the intermediate layer, and this pinhole has been avoided. . However, in the intermediate layer composed of the filler resin dispersion system as disclosed (see, for example, Patent Documents 5 to 14), in addition to the high cost of fillers of submicron or less, which is made into ultrafine particles, The workability is poor due to the excessive bulkiness and cannot be used for manufacturing. For this reason, fine particles of submicron (minimum primary particle is about 0.3 μm) are often used. For this reason, reaggregation of the filler occurs during dispersion or coating film formation, and as a result, a coating film defect of 1 μm or more may occur, and for the design of a photoreceptor having uniform charging property and potential holding property. An intermediate layer is not formed.

On the other hand, in recent years, writing has been densified, and toner used for development has been made finer, and image resolution has been improved. In addition, colorization has progressed, and the ratio of full-color images and halftone images has increased. Under such circumstances, a major issue is how to stabilize the electrostatic characteristics of the photosensitive member even when it is repeatedly used or when the usage environment varies. Various attempts have been made so far, but no satisfactory technique has been completed.
JP 47-6341 A JP-A-60-66258 Japanese Patent Laid-Open No. 52-10138 JP 58-105155 A Japanese Patent Laid-Open No. 58-58556 Japanese Unexamined Patent Publication No. 60-111255 JP 59-17557 A JP-A-60-32054 JP-A 64-68762 JP-A 64-68763 JP-A 64-73352 JP-A 64-73353 JP-A 1-1118848 Japanese Patent Laid-Open No. 1-118849

  Accordingly, the present invention has been made in view of the above, and there is little variation in the electrostatic characteristics of the photosensitive member with respect to the environmental variation in which the image forming apparatus is placed or the like when the image forming apparatus is used repeatedly. An object of the present invention is to provide an electrophotographic photosensitive member with less occurrence of the above. Another object of the present invention is to provide an image forming apparatus and a full color image forming apparatus that can always output a stable image by using this electrophotographic photosensitive member. It is another object of the present invention to provide a process cartridge that is highly convenient to handle.

  Along with advances in image forming devices, miniaturization, high speed, color, and high image quality (high definition) have been promoted, but such a concept is stable and can be maintained for a long time. There is a need. In order to achieve such a state, it is required that the electrostatic characteristics of the electrophotographic photosensitive member used in the image forming apparatus always operate stably and have high durability.

  The electrostatic characteristics of the photoreceptor are the unexposed portion potential and the exposed portion potential in the image forming apparatus, and how these change stably. The former is determined by the chargeability and charge retention of the photoreceptor, and the latter is determined by the photosensitivity and residual potential of the photoreceptor. The present inventors have found that these can be stably maintained by incorporating a specific electron transport agent in the photosensitive layer.

  On the other hand, with regard to high durability, the problem is how to extend the life of the photoreceptor determined by the process (cause) for determining the rate of durability. In the current image forming apparatus, negative / positive development is the mainstream, and the biggest problem with this development method is background stain (background stain). This is a problem of charge blocking between the conductive support and the photosensitive layer, and is considered to be a phenomenon caused by leakage of charges having a polarity opposite to that of the main charge. In order to suppress this phenomenon, it has been found that durability is improved by using a specific undercoat layer (intermediate layer).

The present invention is based on the above-described knowledge of the present inventor, and means for solving the above problems are as follows. That is,
(1) An electrophotographic photosensitive member having at least a photosensitive layer on a conductive support, wherein the surface of the conductive support is anodized, and the photosensitive layer has the following formula (1) An electrophotographic photoreceptor comprising an electron transport agent represented by the formula:

（式中、Ｒ１、Ｒ２は、それぞれ独立に水素原子、置換又は無置換のアルキル基、置換又は無置換のシクロアルキル基、置換又は無置換のアラルキル基からなる群より選ばれる基を表し、Ｒ３、Ｒ４、Ｒ５、Ｒ６、Ｒ７、Ｒ８、Ｒ９、Ｒ１０はそれぞれ独立に水素原子、ハロゲン原子、シアノ基、ニトロ基、アミノ基、水酸基、置換又は無置換のアルキル基、置換又は無置換のシクロアルキル基、置換又は無置換のアラルキル基からなる群より選ばれる基を表す。）
（２）前記陽極酸化被膜がアルマイトであることを特徴とする前記第（１）に記載の電子写真感光体。

Wherein R 1 and R 2 each independently represent a group selected from the group consisting of a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted aralkyl group, and R 3 , R4, R5, R6, R7, R8, R9, R10 are each independently a hydrogen atom, a halogen atom, a cyano group, a nitro group, an amino group, a hydroxyl group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group. Represents a group selected from the group consisting of a group, a substituted or unsubstituted aralkyl group.)
(2) The electrophotographic photosensitive member as described in (1) above, wherein the anodized film is alumite.

  (3) The electrophotographic photosensitive member as described in (2) above, wherein the alumite is subjected to a sealing treatment after an anodized film treatment.

  (4) The electrophotographic photosensitive member according to any one of (1) to (3), wherein the thickness of the alumite is 1 μm or more and 15 μm or less.

  (5) The charge generating material contained in the photosensitive layer is titanyl phthalocyanine having a maximum diffraction peak at 27.2 ° as a diffraction peak (± 0.2 °) with a Bragg angle 2θ with respect to the characteristic X-ray of CuKα. The electrophotographic photosensitive member according to any one of (1) to (4), wherein:

  (6) The charge generating material contained in the photosensitive layer has a maximum diffraction peak at 27.2 ° as a diffraction peak (± 0.2 °) with a Bragg angle 2θ with respect to the characteristic X-ray of CuKα, and 9 It has major peaks at .4 °, 9.6 °, and 24.0 °, and has a peak at 7.3 ° as the lowest diffraction peak, and the peak at 7.3 ° and 9.4 °. It is a titanyl phthalocyanine crystal that does not have a peak between the peaks at ° and does not have a peak at 26.3 °, and is any one of the above (1) to (4), Electrophotographic photoreceptor.

  (7) The electrophotographic photosensitive member according to (6), wherein the average particle size of the titanyl phthalocyanine is 0.25 μm or less.

  (8) An electrophotographic method in which at least charging, image exposure, development, and transfer are repeatedly performed on an electrophotographic photosensitive member, wherein the electrophotographic photosensitive member is any one of (1) to (7). An electrophotographic method, which is an electrophotographic photosensitive member.

  (9) The electrophotographic method according to (8), wherein an alternating current component is superimposed on a direct current component and applied to a charging member to charge the photosensitive member.

  (10) The electrophotographic method as described in (8) or (9) above, wherein the charging means is a charging member disposed in contact with or close to the photoreceptor.

  (11) An electrophotographic apparatus comprising at least a charging means, an image exposing means, a developing means, a transferring means, and an electrophotographic photosensitive member, wherein the electrophotographic photosensitive member is any one of (1) to (7) An image forming apparatus comprising the electrophotographic photosensitive member according to claim 1.

  (12) At least a photosensitive member, a charging device that uniformly charges the surface of the photosensitive member, an image exposure device that forms an electrostatic latent image by performing image exposure after uniform charging, and a toner on the electrostatic latent image A full-color image forming apparatus in which a plurality of image forming elements are arranged, and the electrophotographic photosensitive member according to any one of (1) to (7) is mounted. A full color image forming apparatus.

  (13) At least an electrophotographic photosensitive member that can be attached to and detached from the apparatus main body and is rotated or rotated; a developing unit that develops a latent image formed on the electrophotographic photosensitive member; and an image after image transfer An electrophotographic photosensitive member according to any one of (1) to (7), wherein the electrophotographic photosensitive member is a process cartridge for an image forming apparatus having a cleaning unit that cleans the surface of the carrier. A process cartridge characterized by being a body.

  (14) An image forming apparatus comprising the process cartridge according to (13).

  (15) A full-color image forming apparatus comprising the process cartridge according to (13).

  Therefore, according to the present invention, there can be provided an electrophotographic photosensitive member that can solve various problems in the prior art, has stable electrostatic characteristics in a wide range of environments, and can maintain a stable state for a long period of time. Also, by using this, an image forming apparatus and a full-color image forming apparatus capable of performing high-quality image formation over a long period of time in a wide range of environments are provided. In addition, a process cartridge with high convenience in handling is provided.

  Hereinafter, the configuration of the electrophotographic photosensitive member of the present invention will be described with reference to the drawings.

  FIG. 1 is a sectional view showing the structure of the electrophotographic photosensitive member of the present invention. A photosensitive layer 33 is provided on a conductive support 31 having an anodized film 32 provided on the surface thereof.

  FIG. 2 is a cross-sectional view showing another structural example of the electrophotographic photosensitive member of the present invention, in which a charge generation layer 35 and a charge transport layer are formed on a conductive support 31 having an anodized film 32 provided on the surface. 37 is provided.

  FIG. 3 is a cross-sectional view showing still another configuration of the present invention. On a conductive support 31 having an anodized film 32 provided on the surface, a charge generation layer 35, a charge transport layer 37, and a protective layer 39 are provided. Is provided.

  Examples of the conductive support 31 include a conductive material having a volume resistance of 1010 Ω · cm or less, for example, a metal such as aluminum, nickel, chromium, nichrome, copper, gold, silver, or platinum, or a metal such as tin oxide or indium oxide. Oxide is deposited or sputtered on a film or cylindrical plastic, paper, or a plate of aluminum, aluminum alloy, nickel, stainless steel, etc. Later, pipes that have been subjected to surface treatment such as cutting, superfinishing, and polishing can be used. An endless nickel belt or an endless stainless steel belt can also be used as the conductive support 31. In addition, the conductive support 31 of the present invention can be used in which conductive powder is dispersed in a suitable binder resin and coated on the support. 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. It is done. The binder resin used at the same time is polystyrene, styrene-acrylonitrile copolymer, styrene-butadiene copolymer, styrene-maleic anhydride copolymer, polyester, polyvinyl chloride, vinyl chloride-vinyl acetate copolymer. , Polyvinyl acetate, polyvinylidene chloride, polyarylate resin, phenoxy resin, polycarbonate, cellulose acetate resin, ethyl cellulose resin, polyvinyl butyral, polyvinyl formal, polyvinyl toluene, poly-N-vinyl carbazole, acrylic resin, silicone resin, epoxy resin, Examples thereof include thermoplastic, thermosetting resins, and photocurable resins such as melamine resin, urethane resin, phenol resin, and alkyd resin. Such a conductive layer can be provided by dispersing and coating these conductive powder and binder resin in a suitable solvent such as tetrahydrofuran, dichloromethane, methyl ethyl ketone, and toluene.

  Among these, a cylindrical support made of aluminum that can be easily subjected to an anodized film treatment can be most preferably used. As used herein, aluminum includes both pure aluminum and aluminum alloys. Specifically, JIS 1000, 3000, and 6000 series aluminum or aluminum alloy is most suitable.

  Next, the anodized film 32 will be described. The anodized film is obtained by anodizing various metals and various alloys in an electrolyte solution. Among them, a film called anodized aluminum or an aluminum alloy that has been anodized in an electrolyte solution is used in the photoreceptor of the present invention. Is most suitable. The anodizing treatment is performed in an acidic bath such as chromic acid, sulfuric acid, oxalic acid, phosphoric acid, boric acid, sulfamic acid. Of these, treatment with a sulfuric acid bath is most suitable. For example, sulfuric acid concentration: 10-20%, bath temperature: 5-25 ° C., current density: 1-4 A / dm 2, electrolysis voltage: 5-30 V, treatment time: about 5-60 minutes Although it is performed, it is not limited to this. Since the anodic oxide film thus produced is porous and has high insulation, the surface is very unstable. For this reason, there is a change with time after fabrication, and the physical property value of the anodized film is likely to change. In order to avoid this, it is desirable to further seal the anodized film. Examples of the sealing treatment include a method of immersing the anodized film in an aqueous solution containing nickel fluoride and nickel acetate, a method of immersing the anodized film in boiling water, and a method of treating with pressurized steam. Among these, the method of immersing in the aqueous solution containing nickel acetate is the most preferable. Subsequent to the sealing treatment, the anodic oxide film is washed. The main purpose of this is to remove excess metal salts and the like attached by the sealing treatment. If this remains excessively on the surface of the support (anodized film), it not only adversely affects the quality of the coating film formed on this surface, but also generally low resistance components remain, resulting in the occurrence of soiling. It can also be a cause. The cleaning may be performed once with pure water, but is usually performed at another stage. At this time, it is preferable that the final cleaning liquid is as clean as possible (deionized). Moreover, it is desirable to perform physical rubbing cleaning with a contact member in one of the other cleaning processes.

  The film thickness of the anodized film formed as described above is preferably about 1 to 15 μm. More desirably, it is about 5 to 10 μm. If it is thinner than this, the effect of the barrier property as an anodic oxide film is not sufficient, and if it is thicker than this, the time constant as an electrode becomes too large, resulting in the generation of residual potential and the response of the photoreceptor. There is a case.

  In the photoreceptor of the present invention, an undercoat layer can be provided between the anodized film 32 and the photosensitive layer (charge generation layer). In general, the undercoat layer is mainly composed of a resin. However, considering that the photosensitive layer is coated with a solvent on these resins, the resin may be a resin having high solvent resistance with respect to a general organic solvent. desirable. Examples of such resins include water-soluble resins such as polyvinyl alcohol, casein, and sodium polyacrylate, alcohol-soluble resins such as copolymer nylon and methoxymethylated nylon, polyurethane, melamine resin, phenol resin, alkyd-melamine resin, and epoxy. Examples thereof include a curable resin that forms a three-dimensional network structure such as a resin. Further, a metal oxide fine powder pigment exemplified by titanium oxide, silica, alumina, zirconium oxide, tin oxide, indium oxide and the like may be added to the undercoat layer in order to prevent moire and reduce residual potential.

  These undercoat layers can be formed using an appropriate solvent and coating method as in the above-mentioned photosensitive layer. Furthermore, a silane coupling agent, a titanium coupling agent, a chromium coupling agent, or the like can be used as the undercoat layer of the present invention. In addition, for the undercoat layer of the present invention, a vacuum thin film is formed of Al2O3 provided by anodization, organic substances such as polyparaxylylene (parylene), and inorganic substances such as SiO2, SnO2, TiO2, ITO, CeO2. Those provided by the law can also be used satisfactorily. In addition, known ones can be used. The thickness of the undercoat layer is suitably from 0 to 5 μm.

  Next, the photosensitive layer will be described. The photosensitive layer may be a single layer photosensitive layer (FIG. 1) containing a charge generation material and a charge transport material, but a layered type (FIGS. 2 and 3) composed of a charge generation layer and a charge transport layer is sensitive. It exhibits excellent durability and is used well. For convenience of explanation, the photosensitive layer having a laminated structure will be described first.

  The charge generation layer is a layer mainly composed of a charge generation material. The charge generation material is not particularly limited, and a known material can be used. Among them, titanyl phthalocyanine having a maximum diffraction peak at 27.2 ° as a diffraction peak (± 0.2 °) with a Bragg angle 2θ with respect to the characteristic X-ray (wavelength 1.542 mm) of CuKα can be used effectively. In particular, as a diffraction peak (± 0.2 °) at a Bragg angle 2θ with respect to the characteristic X-ray (wavelength 1.542 mm) of the crystal type and CuKα described in Japanese Patent Laid-Open No. 2001-19871, the maximum diffraction is at least 27.2 °. It has a peak, and further has main peaks at 9.4 °, 9.6 °, and 24.0 °, and has a peak at 7.3 ° as the lowest diffraction peak, and 7.3 °. A titanyl phthalocyanine crystal having no peak between the peak at 9.4 ° and a peak at 9.4 ° is preferably used, and a crystal having no peak at 26.3 ° can be used effectively. Further, it has the above crystal type, and has an average particle size of 0.25 μm or less at the time of crystal synthesis or by dispersion filtration treatment, and has no coarse particles (Japanese Patent Laid-Open Nos. 2004-83859 and 2004-2004). 78141) is most useful.

  In the charge generation layer, the charge generation material is dispersed in a suitable solvent together with a binder resin as necessary using a ball mill, attritor, sand mill, ultrasonic wave, etc., and this is applied onto a conductive support and dried. It is formed by doing.

  As the binder resin used in the charge generation layer as necessary, the binder resin used in the charge generation layer as needed may be polyamide, polyurethane, epoxy resin, polyketone, polycarbonate, silicon resin, acrylic resin, polyvinyl Butyral, polyvinyl formal, polyvinyl ketone, polystyrene, polysulfone, poly-N-vinylcarbazole, polyacrylamide, polyvinyl benzal, polyester, phenoxy resin, vinyl chloride-vinyl acetate copolymer, polyvinyl acetate, polyphenylene oxide, polyamide, polyvinyl Examples thereof include pyridine, cellulose resin, casein, polyvinyl alcohol, and polyvinyl pyrrolidone. The amount of the binder resin is suitably 0 to 500 parts by weight, preferably 10 to 300 parts by weight with respect to 100 parts by weight of the charge generating material.

  Examples of the solvent used here include isopropanol, acetone, methyl ethyl ketone, cyclohexanone, tetrahydrofuran, dioxane, ethyl cellosolve, ethyl acetate, methyl acetate, dichloromethane, dichloroethane, monochlorobenzene, cyclohexane, toluene, xylene, ligroin and the like. As a coating method for the coating solution, a dip coating method, spray coating, beat coating, nozzle coating, spinner coating, ring coating, or the like can be used. The film thickness of the charge generation layer is suitably about 0.01 to 5 μm, preferably 0.1 to 2 μm.

  The charge transport layer can be formed by dissolving or dispersing a charge transport material and a binder resin in an appropriate solvent, and applying and drying the solution on the charge generation layer. Moreover, a plasticizer, a leveling agent, antioxidant, etc. can also be added as needed.

  Charge transport materials include hole transport materials and electron transport materials. Examples of hole transport materials include poly-N-vinylcarbazole and derivatives thereof, poly-γ-carbazolylethyl glutamate and derivatives thereof, pyrene-formaldehyde condensates and derivatives thereof, polyvinylpyrene, polyvinylphenanthrene, polysilane, 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, pyrazolines Derivatives, divinylbenzene derivatives, hydrazone derivatives, indene derivatives, butadiene derivatives, pyrene derivatives, etc., bisstilbene derivatives, enamine derivatives, etc. Other known materials may be mentioned. These charge transport materials may be used alone or in combination of two or more.

  Examples of the electron transporting material include chloroanil, bromoanil, tetracyanoethylene, tetracyanoquinodimethane, 2,4,7-trinitro-9-fluorenone, 2,4,5,7-tetranitro-9-fluorenone, 2,4 , 5,7-tetranitroxanthone, 2,4,8-trinitrothioxanthone, 2,6,8-trinitro-4H-indeno [1,2-b] thiophen-4-one, 1,3,7-tri Examples thereof include electron-accepting substances such as nitrodibenzothiophene-5,5-dioxide and benzoquinone derivatives.

  Binder resins include polystyrene, styrene-acrylonitrile copolymer, styrene-butadiene copolymer, styrene-maleic anhydride copolymer, polyester, polyvinyl chloride, vinyl chloride-vinyl acetate copolymer, polyvinyl acetate, poly Vinylidene chloride, polyarate, phenoxy resin, polycarbonate, cellulose acetate resin, ethyl cellulose resin, polyvinyl butyral, polyvinyl formal, polyvinyl toluene, poly-N-vinyl carbazole, acrylic resin, silicone resin, epoxy resin, melamine resin, urethane resin, phenol resin And thermoplastic or thermosetting resins such as alkyd resins.

  The amount of the charge transport material is 20 to 300 parts by weight, preferably 40 to 150 parts by weight, with respect to 100 parts by weight of the binder resin. The thickness of the charge transport layer is preferably about 5 to 100 μm.

  As the solvent used here, tetrahydrofuran, dioxane, toluene, dichloromethane, monochlorobenzene, dichloroethane, cyclohexanone, methyl ethyl ketone, acetone and the like are used. Among them, the use of a non-halogen solvent is desirable for the purpose of reducing the environmental load. Specifically, cyclic ethers such as tetrahydrofuran, dioxolane and dioxane, aromatic hydrocarbons such as toluene and xylene, and derivatives thereof are preferably used.

  In addition, a polymer charge transport material having a function as a charge transport material and a function of a binder resin is also preferably used for the charge transport layer. The charge transport layer 37 composed of these polymer charge transport materials is excellent in wear resistance. As the polymer charge transport material, known materials can be used, and in particular, a polycarbonate containing a triarylamine structure in the main chain and / or side chain is preferably used. Among these, polymer charge transport materials represented by the formulas (I) to (X) are favorably used, and these are exemplified below and specific examples are shown.

式中、Ｒ_１、Ｒ_２、Ｒ_３はそれぞれ独立して置換もしくは無置換のアルキル基又はハロゲン原子、Ｒ_４は水素原子又は置換もしくは無置換のアルキル基、Ｒ_５、Ｒ_６は置換もしくは無置換のアリール基、ｏ、ｐ、ｑはそれぞれ独立して０乃至４の整数、ｋ、ｊは組成を表し、０．１≦ｋ≦１、０≦ｊ≦０．９、ｎは繰り返し単位数を表し５乃至５０００の整数である。Ｘは脂肪族の２価基、環状脂肪族の２価基、または下記一般式で表される２価基を表す。尚、（Ｉ）式は２つの共重合種が交互共重合体の形で記載されているが、ランダム共重合体でも構わない。

In the formula, R ₁ , R ₂ and R ₃ are each independently a substituted or unsubstituted alkyl group or a halogen atom, R ₄ is a hydrogen atom or a substituted or unsubstituted alkyl group, and R ₅ and R ₆ are substituted or unsubstituted. Substituted aryl group, o, p, q are each independently an integer of 0 to 4, k, j are compositions, 0.1 ≦ k ≦ 1, 0 ≦ j ≦ 0.9, n is the number of repeating units Represents an integer of 5 to 5000. X represents an aliphatic divalent group, a cycloaliphatic divalent group, or a divalent group represented by the following general formula. In the formula (I), two copolymer species are described in the form of an alternating copolymer, but a random copolymer may be used.

Ｒ_１０１、Ｒ_１０２は各々独立して置換もしくは無置換のアルキル基、アリール基またはハロゲン原子を表す。ｌ、ｍは０乃至４の整数、Ｙは単結合、炭素原子数１乃至１２の直鎖状、分岐状もしくは環状のアルキレン基、−Ｏ−、−Ｓ−、−ＳＯ−、−ＳＯ_２−、−ＣＯ−、−ＣＯ−Ｏ−Ｚ−Ｏ−ＣＯ−（式中Ｚは脂肪族の２価基を表す。）または、

R ₁₀₁ and R ₁₀₂ each independently represents a substituted or unsubstituted alkyl group, aryl group or halogen atom. l and m are integers of 0 to 4, Y is a single bond, a linear, branched or cyclic alkylene group having 1 to 12 carbon atoms, —O—, —S—, —SO—, —SO ₂ —. , -CO-, -CO-O-Z-O-CO- (wherein Z represents an aliphatic divalent group) or

（ａは１乃至２０の整数、ｂは１乃至２０００の整数、Ｒ_１０３、Ｒ_１０４は置換または無置換のアルキル基又はアリール基を表す）を表す。ここで、Ｒ_１０１とＲ_１０２、Ｒ_１０３とＲ_１０４は、それぞれ同一でも異なってもよい。）

(A represents an integer of 1 to 20, b represents an integer of 1 to 2000, and R ₁₀₃ and R ₁₀₄ represent a substituted or unsubstituted alkyl group or aryl group). Here, R ₁₀₁ and R ₁₀₂ , and R ₁₀₃ and R ₁₀₄ may be the same or different. )

式中、Ｒ_７、Ｒ_８は置換もしくは無置換のアリール基、Ａｒ_１, Ａｒ_２, Ａｒ_３は同一又は異なるアリレン基を表す。Ｘ，ｋ，ｊおよびｎは、（Ｉ）式の場合と同じである。尚、（II）式は２つの共重合種が交互共重合体の形で記載されているが、ランダム共重合体でも構わない。

In the formula, R ₇ and R ₈ represent a substituted or unsubstituted aryl group, and Ar ₁ , Ar ₂ , and Ar ₃ represent the same or different arylene groups. X, k, j and n are the same as in the case of formula (I). In the formula (II), two copolymer species are described in the form of an alternating copolymer, but a random copolymer may be used.

式中、Ｒ_９, Ｒ_１０は置換もしくは無置換のアリール基、Ａｒ_４，Ａｒ_５，Ａｒ_６は同一又は異なるアリレン基を表す。Ｘ，ｋ，ｊおよびｎは、（Ｉ）式の場合と同じである。尚、（III）式は２つの共重合種が交互共重合体の形で記載されているが、ランダム共重合体でも構わない。

In the formula, R ₉ and R ₁₀ represent a substituted or unsubstituted aryl group, and Ar ₄ , Ar ₅ , and Ar ₆ represent the same or different arylene groups. X, k, j and n are the same as in the case of formula (I). In the formula (III), two copolymer species are described in the form of an alternating copolymer, but a random copolymer may be used.

式中、Ｒ_１１, Ｒ_１２は置換もしくは無置換のアリール基、Ａｒ_７, Ａｒ_８, Ａｒ_９は同一又は異なるアリレン基、ｐは１乃至５の整数を表す。Ｘ，ｋ，ｊおよびｎは、（Ｉ）式の場合と同じである。尚、（IV）式は２つの共重合種が交互共重合体の形で記載されているが、ランダム共重合体でも構わない。

In the formula, R ₁₁ and R ₁₂ are substituted or unsubstituted aryl groups, Ar ₇ , Ar ₈ and Ar ₉ are the same or different arylene groups, and p represents an integer of 1 to 5. X, k, j and n are the same as in the case of formula (I). In the formula (IV), two copolymer species are described in the form of an alternating copolymer, but a random copolymer may be used.

式中、Ｒ_１３，Ｒ_１４は置換もしくは無置換のアリール基、Ａｒ_１０，Ａｒ_１１，Ａｒ_１２は同一又は異なるアリレン基、Ｘ_１，Ｘ_２は置換もしくは無置換のエチレン基、又は置換もしくは無置換のビニレン基を表す。Ｘ，ｋ，ｊおよびｎは、（VI）式の場合と同じである。尚、（VI）式は２つの共重合種が交互共重合体の形で記載されているが、ランダム共重合体でも構わない。

In the formula, R ₁₃ and R ₁₄ are substituted or unsubstituted aryl groups, Ar ₁₀ , Ar ₁₁ and Ar ₁₂ are the same or different arylene groups, X ₁ and X ₂ are substituted or unsubstituted ethylene groups, or substituted or unsubstituted Represents a substituted vinylene group. X, k, j and n are the same as in the case of the formula (VI). In the formula (VI), two copolymer species are described in the form of an alternating copolymer, but a random copolymer may be used.

式中、Ｒ_１５，Ｒ_１６，Ｒ_１７，Ｒ_１８は置換もしくは無置換のアリール基、Ａｒ_１３，Ａｒ_１４，Ａｒ_１５，Ａｒ_１６は同一又は異なるアリレン基、Ｙ_１，Ｙ_２，Ｙ_３は単結合、置換もしくは無置換のアルキレン基、置換もしくは無置換のシクロアルキレン基、置換もしくは無置換のアルキレンエーテル基、酸素原子、硫黄原子、ビニレン基を表し同一であっても異なってもよい。Ｘ，ｋ，ｊおよびｎは、（VI）式の場合と同じである。尚、（VI）式は２つの共重合種が交互共重合体の形で記載されているが、ランダム共重合体でも構わない。

In the formula, R ₁₅ , R ₁₆ , R ₁₇ and R ₁₈ are substituted or unsubstituted aryl groups, Ar ₁₃ , Ar ₁₄ , Ar ₁₅ and Ar ₁₆ are the same or different arylene groups, and Y ₁ , Y ₂ and Y ₃ are 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 may be the same or different. X, k, j and n are the same as in the case of the formula (VI). In the formula (VI), two copolymer species are described in the form of an alternating copolymer, but a random copolymer may be used.

式中、Ｒ_１９，Ｒ_２０は水素原子、置換もしくは無置換のアリール基を表し，Ｒ_１９とＲ_２０は環を形成していてもよい。Ａｒ_１７，Ａｒ_１８，Ａｒ_１９は同一又は異なるアリレン基を表す。Ｘ，ｋ，ｊおよびｎは、（Ｉ）式の場合と同じである。尚、（VII）式は２つの共重合種が交互共重合体の形で記載されているが、ランダム共重合体でも構わない。

In the formula, R ₁₉ and R _{20 each} represent a hydrogen atom or a substituted or unsubstituted aryl group, and R ₁₉ and R ₂₀ may form a ring. Ar ₁₇ , Ar ₁₈ and Ar ₁₉ represent the same or different arylene groups. X, k, j and n are the same as in the case of formula (I). In the formula (VII), two copolymer species are described in the form of an alternating copolymer, but a random copolymer may be used.

式中、Ｒ_２１は置換もしくは無置換のアリール基、Ａｒ_２０，Ａｒ_２１，Ａｒ_２２，Ａｒ_２３は同一又は異なるアリレン基を表す。Ｘ，ｋ，ｊおよびｎは、（Ｉ）式の場合と同じである。尚、（VIII）式は２つの共重合種が交互共重合体の形で記載されているが、ランダム共重合体でも構わない。

In the formula, R ₂₁ represents a substituted or unsubstituted aryl group, and Ar ₂₀ , Ar ₂₁ , Ar ₂₂ , and Ar ₂₃ represent the same or different arylene groups. X, k, j and n are the same as in the case of formula (I). In the formula (VIII), two copolymer species are described in the form of an alternating copolymer, but a random copolymer may be used.

式中、Ｒ_２２，Ｒ_２３，Ｒ_２４，Ｒ_２５は置換もしくは無置換のアリール基、Ａｒ_２４，Ａｒ_２５，Ａｒ_２６，Ａｒ_２７，Ａｒ_２８は同一又は異なるアリレン基を表す。Ｘ，ｋ，ｊおよびｎは、（Ｉ）式の場合と同じである。尚、（IX）式は２つの共重合種が交互共重合体の形で記載されているが、ランダム共重合体でも構わない。

In the formula, R ₂₂ , R ₂₃ , R ₂₄ and R ₂₅ represent a substituted or unsubstituted aryl group, and Ar ₂₄ , Ar ₂₅ , Ar ₂₆ , Ar ₂₇ and Ar ₂₈ represent the same or different arylene groups. X, k, j and n are the same as in the case of formula (I). In the formula (IX), two copolymer species are described in the form of an alternating copolymer, but a random copolymer may be used.

式中、Ｒ_２６，Ｒ_２７は置換もしくは無置換のアリール基、Ａｒ_２９，Ａｒ_３０，Ａｒ_３１は同一又は異なるアリレン基を表す。Ｘ，ｋ，ｊおよびｎは、（Ｉ）式の場合と同じである。尚、（Ｘ）式は２つの共重合種が交互共重合体の形で記載されているが、ランダム共重合体でも構わない。

In the formula, R ₂₆ and R ₂₇ represent a substituted or unsubstituted aryl group, and Ar ₂₉ , Ar ₃₀ and Ar ₃₁ represent the same or different arylene groups. X, k, j and n are the same as in the case of formula (I). In the formula (X), two copolymer species are described in the form of an alternating copolymer, but a random copolymer may be used.

  Further, as the polymer charge transport material used in the charge transport layer, in addition to the polymer charge transport material described above, in the state of the monomer or oligomer having an electron donating group at the time of film formation of the charge transport layer, A polymer having a two-dimensional or three-dimensional crosslinked structure is finally included by carrying out a curing reaction or a crosslinking reaction.

  Further, a charge transport layer having a crosslinked structure is also effectively used as the structure of the charge transport layer. Regarding the formation of a cross-linked structure, a reactive monomer having a plurality of cross-linkable functional groups in one molecule is used to cause a cross-linking reaction using light or thermal energy to form a three-dimensional network structure. is there. This network structure functions as a binder resin and exhibits high wear resistance.

  Moreover, it is a very effective means to use a monomer having a charge transporting ability in whole or in part as the reactive monomer. By using such a monomer, a charge transport site is formed in the network structure, and the function as the charge transport layer can be sufficiently expressed. A reactive monomer having a triarylamine structure is effectively used as the monomer having charge transporting ability.

  The charge transport layer having such a network structure has high wear resistance, but has a large volume shrinkage during the crosslinking reaction, and if it is too thick, cracks may occur. In such a case, the charge transport layer has a laminated structure, the lower layer (charge generation layer side) uses a low molecular dispersion polymer charge transport layer, and the upper layer (surface side) has a cross-linked structure. It may be formed.

  A charge transport layer composed of a polymer having these electron donating groups or a polymer having a crosslinked structure is excellent in wear resistance. Usually, in the electrophotographic process, since the charging potential (unexposed portion potential) is constant, if the surface layer of the photoreceptor is worn by repeated use, the electric field strength applied to the photoreceptor increases accordingly. As the electric field strength increases, the occurrence frequency of scumming increases. Therefore, the high wear resistance of the photosensitive member is advantageous for scumming. The charge transport layer composed of a polymer having these electron donating groups is a polymer compound, so it has excellent film-forming properties and has a charge transport site compared to a charge transport layer composed of a low molecular weight dispersed polymer. It can be configured with high density and has excellent charge transport capability. For this reason, a photoreceptor having a charge transport layer using a polymer charge transport material can be expected to have a high response speed.

  Examples of the other polymer having an electron donating group include a copolymer of a known monomer, a block polymer, a graft polymer, a star polymer, and, for example, JP-A-3-109406, JP-A-2000- It is also possible to use a crosslinked polymer having an electron donating group as disclosed in JP-A-206723 and JP-A-2001-34001.

  In the present invention, a plasticizer or a leveling agent may be added to the charge transport layer. As the plasticizer, those used as plasticizers for general resins such as dibutyl phthalate and dioctyl phthalate can be used as they are, and the amount used is suitably about 0 to 30% by weight based on the binder resin. As the leveling agent, silicone oils such as dimethyl silicone oil and methylphenyl silicone oil, and polymers or oligomers having a perfluoroalkyl group in the side chain are used, and the amount used is 0 to 0 with respect to the binder resin. 1% by weight is suitable.

In the above description, the photosensitive layer has a laminated structure. However, in the present invention, the photosensitive layer may have a single layer structure. In order to make the photosensitive layer as a single layer, the photosensitive layer is constituted by providing a single layer containing at least the above-described charge generating substance and a binder resin. As the binder resin, the description of the charge generating layer and the charge transport layer is used. Those described in the above are used well. In addition, when a charge transport material is used in combination with the single-layer photosensitive layer, high photosensitivity, high carrier transport properties, and low residual potential are exhibited, and the single layer photosensitive layer can be used favorably. At this time, as the charge transport material to be used, either a hole transport material or an electron transport material is selected according to the polarity charged on the surface of the photoreceptor. Furthermore, since the above-described polymer charge transporting material also has the functions of a binder resin and a charge transporting material, it is favorably used for a single-layer photosensitive layer.
In the present invention, the electron transfer agent represented by the following formula (1) is contained in the photosensitive layer.

（式中、Ｒ１、Ｒ２は、それぞれ独立に水素原子、置換又は無置換のアルキル基、置換又は無置換のシクロアルキル基、置換又は無置換のアラルキル基からなる群より選ばれる基を表し、Ｒ３、Ｒ４、Ｒ５、Ｒ６、Ｒ７、Ｒ８、Ｒ９、Ｒ１０はそれぞれ独立に水素原子、ハロゲン原子、シアノ基、ニトロ基、アミノ基、水酸基、置換又は無置換のアルキル基、置換又は無置換のシクロアルキル基、置換又は無置換のアラルキル基からなる群より選ばれる基を表す。）
上述した感光層構成と併せてその添加方法について示す。

Wherein R 1 and R 2 each independently represent a group selected from the group consisting of a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted aralkyl group, and R 3 , R4, R5, R6, R7, R8, R9, R10 are each independently a hydrogen atom, a halogen atom, a cyano group, a nitro group, an amino group, a hydroxyl group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group. Represents a group selected from the group consisting of a group, a substituted or unsubstituted aralkyl group.)
The addition method will be described together with the photosensitive layer structure described above.

  When the photosensitive layer has a single layer structure, it is used as an electron transport material. Depending on whether the photocarrier generation site is in the vicinity of the photoreceptor surface or deep in the bulk, if it is configured to move holes to the main, it looks like an additive (meaning that it is not the main material used in large quantities) It is used as a main charge (electron) transport material when electrons are moved to the main. Specifically, when the single-layer photosensitive layer is used with a positive charge and generates photocarriers in the vicinity of the surface of the photosensitive layer, the holes in the photosensitive layer mainly travel a long distance. It will be. In this case, the main charge transport material is a hole transport material, and the electron transport agent of the formula (1) is used as an electron transfer material to the surface. On the other hand, when photocarriers are generated in the deep part of the bulk (support side), the electrons move to the main. In this case, the electron transport agent of formula (1) is used as the main charge transport material. The When the charging polarity is negatively charged, the above description is reversed.

  When the photosensitive layer has a laminated structure, the added layer may be different depending on the charging polarity. The photosensitive layer is laminated in the order of the charge generation layer / charge transport layer, but when used in a negative charge, holes move to the main. Therefore, the electron transport agent of the above formula (1) is used in the form of an additive when added to the charge transport layer, and is used as an electron transport material when added to the charge generation layer. The On the other hand, when it is used with positive charging, electrons move to the main. For this reason, the electron transport agent of the above formula (1) is used as a charge transport material when used in the charge transport layer. When used in the charge generation layer, it is used in the form of an additive.

  In the electrophotographic photoreceptor of the present invention, a protective layer may be provided on the photosensitive layer for the purpose of protecting the photosensitive layer. In recent years, computers have been used on a daily basis, and there is a demand for miniaturization of devices as well as high-speed output by printers. Therefore, by providing a protective layer and improving the durability, it is possible to effectively use the photosensitive member of the present invention having no abnormal defect.

  Examples of the protective layer that can be used in the present invention include a protective layer in which a filler described in JP 2002-278120 A is dispersed, a photocrosslinking protective layer described in JP 2005-115353 A, JP 2002-31911 A, and the like. A charge injection layer described in Japanese Patent Publication No. Gazette and the like can be used.

  Next, the image forming apparatus of the present invention will be described in detail with reference to the drawings.

  FIG. 4 is a schematic diagram for explaining the image forming process and the image forming apparatus of the present invention, and the following modifications also belong to the category of the present invention.

  In FIG. 4, the photoreceptor 1 is provided with at least an anodic oxide film and a photosensitive layer on a conductive support, and the photosensitive layer contains an electron transport agent represented by the formula (1). Although the photoconductor has a drum shape, it may have a sheet shape or an endless belt shape. The charging roller 3, the pre-transfer charger 7, the transfer charger 10, the separation charger 11, and the pre-cleaning charger 13 are known in the art such as a corotron, a scorotron, a solid state charger, a charging roller, and a transfer roller. Means are used.

  Of these charging methods, a contact charging method or a non-contact proximity arrangement method is particularly desirable. The contact charging method has advantages such as high charging efficiency, a small amount of ozone generation, and downsizing of the apparatus. The contact-type charging member here is a type in which the surface of the charging member is in contact with the surface of the photosensitive member, and includes a charging roller, a charging blade, and a charging brush. Of these, charging rollers and charging brushes are used favorably.

  Further, the charging member arranged in the proximity is a type in which the charging member is arranged in a non-contact state so as to have a gap (gap) of 200 μm or less between the surface of the photosensitive member and the surface of the charging member. It is distinguished from known chargers typified by corotron and scorotron from the distance of the gap. The adjacently arranged charging member used in the present invention may have any shape as long as it has a mechanism capable of appropriately controlling the gap with the surface of the photoreceptor. For example, the rotation shaft of the photosensitive member and the rotation shaft of the charging member may be mechanically fixed so as to have an appropriate gap. Among them, using a charging member in the shape of a charging roller, a gap forming member is disposed at both ends of the non-image forming portion of the charging member, and only this portion is brought into contact with the surface of the photoreceptor, and the image forming region is disposed in a non-contact manner. Alternatively, the gap forming member at both ends of the non-photosensitive portion of the photoconductor is disposed, and only this portion is brought into contact with the surface of the charging member, and the image forming region is disposed in a non-contact manner, so that the gap can be stably stabilized. It is a method that can be maintained. In particular, the methods described in JP-A Nos. 2002-148904 and 2002-148905 can be used satisfactorily. An example of the proximity charging mechanism in which the gap forming member is arranged on the charging member side is shown in FIG. By using the above-mentioned method, there are advantages such as high charging efficiency and low ozone generation, miniaturization of the apparatus, no contamination with toner, etc., and no mechanical wear due to contact. Because it is used well. Furthermore, as an application method, there is an advantage that uneven charging is less likely to occur by using AC superposition, and it can be used satisfactorily.

  When such a contact type charging member or a non-contact charging type charging member is used, there is a drawback that dielectric breakdown of the photosensitive member is likely to occur. However, the photoreceptor used in the present invention has an intermediate layer composed of a laminate structure of a charge blocking layer and a moire preventing layer, and further, the photosensitive layer does not contain coarse particles of a charge generating substance. Extremely high pressure resistance. For this reason, the resistance against the dielectric breakdown of the photosensitive member is high, and the merit (prevention of uneven charging) of the charging member can be utilized.

  Although the photosensitive member is charged by such a charging member, in a normal image forming apparatus, since background contamination due to the photosensitive member is likely to occur, the electric field strength applied to the photosensitive member is set to be low ( 40V / μm or less, preferably 30V / μm or less). This is because the occurrence of soiling depends on the electric field strength, and the probability of soiling increases as the electric field strength increases. However, reducing the electric field strength applied to the photoreceptor reduces the efficiency of photocarrier generation and reduces the photosensitivity. In addition, since the electric field strength applied between the surface of the photosensitive member and the conductive support is reduced, the straightness of the photocarrier generated in the photosensitive layer is reduced, and diffusion due to clone repulsion is increased, resulting in a reduction in resolution. Arise. On the other hand, by using the electrophotographic photosensitive member of the present invention, the probability of occurrence of soiling can be extremely reduced, so there is no need to reduce the electric field intensity more than necessary, and it can be used even under an electric field intensity of 40 V / μm or more. become able to. For this reason, a sufficient amount of gain in the attenuation of the photoreceptor light can be secured, a large margin can be created for development (potential) described later, and development can be performed without reducing the resolution.

  The image exposure unit 5 uses a light source capable of ensuring high luminance, such as a light emitting diode (LED), a semiconductor laser (LD), or electroluminescence (EL).

As a light source such as the static elimination lamp 2, general light emitting 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.
Among these light sources, light emitting diodes and semiconductor lasers have high irradiation energy, and have a long wavelength light of 600 to 800 nm. Therefore, the above-mentioned phthalocyanine pigment, which is a charge generation material, exhibits high sensitivity, and is used well. The 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, or a pre-exposure process using light irradiation in addition to the process shown in FIG.

  The toner developed on the photosensitive member 1 by the developing unit 6 is transferred to the transfer paper 9, but not all is transferred, and some toner remains on the photosensitive member 1. Such toner is removed from the photoreceptor by the fur brush 14 and the blade 15. 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.

  When a positive (negative) charge is applied to the electrophotographic photosensitive member and image exposure is performed, a positive (negative) electrostatic latent image is formed on the surface of the photosensitive member. If this is developed with toner of negative (positive) polarity (detection fine particles), a positive image can be obtained, and if developed with toner of positive (negative) polarity, a negative image can be obtained. A known method is applied to the developing unit, and a known method is also used for the charge eliminating unit.

  FIG. 6 shows another example of the electrophotographic process according to the present invention. The photosensitive member 21 is provided with at least an anodized film and a photosensitive layer on a conductive support, and the photosensitive layer contains an electron transporting agent represented by the formula (1). Driven by the driving rollers 22a and 22b, charging by the charger 23, image exposure by the light source 24, development (not shown), transfer using the charger 25, pre-cleaning exposure by the light source 26, cleaning by the brush 27, by the light source 28 Static elimination is repeated.

  The above illustrated electrophotographic process is illustrative of an embodiment of the present invention, and of course other embodiments are possible. For example, in FIG. 6, the pre-cleaning exposure is performed from the support side, but this may be performed from the photosensitive layer side, or irradiation with static elimination light may be performed from the support side.

  On the other hand, in the light irradiation process, image exposure, pre-cleaning exposure, and static elimination exposure are illustrated. In addition, pre-exposure exposure, pre-exposure of image exposure, and other known light irradiation processes are provided to light the photosensitive member. Irradiation can also be performed.

  The image forming means as described above may be fixedly incorporated in a copying apparatus, a facsimile, or a printer, but may be incorporated in these apparatuses in the form of a process cartridge. A process cartridge is a single device (part) that contains a photoconductor and further includes a charging unit, an exposure unit, a developing unit, a transfer unit, a cleaning unit, a neutralizing unit, and the like. There are many shapes and the like of the process cartridge, but a general example is shown in FIG. The photoreceptor 1 is formed by providing at least an anodic oxide film and a photosensitive layer on a conductive support, and the photosensitive layer contains an electron transporting agent represented by the formula (1).

  FIG. 8 is a schematic diagram for explaining the tandem-type full-color electrophotographic apparatus of the present invention, and modifications as described below also belong to the category of the present invention.

  In FIG. 8, reference numerals 1C, 1M, 1Y, and 1K denote drum-shaped photoconductors. The photoconductor 1 is provided with at least an anodized film and a photoconductive layer on a conductive support. 1) It contains an electron transport agent represented by the formula.

  The photoreceptors 1C, 1M, 1Y, and 1K rotate in the direction of the arrow in the figure, and at least around them, the charging members 2C, 2M, 2Y, and 2K, the developing members 4C, 4M, 4Y, and 4K, the cleaning member 5C, and the like. 5M, 5Y, and 5K are arranged. The charging members 2C, 2M, 2Y, and 2K are charging members that constitute a charging device for uniformly charging the surface of the photoreceptor. Laser light 3C, 3M, 3Y, 3K from an exposure member (not shown) is irradiated from the surface of the photoreceptor between the charging members 2C, 2M, 2Y, 2K and the developing members 4C, 4M, 4Y, 4K. Electrostatic latent images are formed on 1C, 1M, 1Y, and 1K. Then, four image forming elements 6C, 6M, 6Y, and 6K centering on such photoreceptors 1C, 1M, 1Y, and 1K are juxtaposed along a transfer conveyance belt 10 that is a transfer material conveyance unit. The transfer conveyance belt 10 contacts the photoreceptors 1C, 1M, 1Y, and 1K between the developing members 4C, 4M, 4Y, and 4K of the image forming units 6C, 6M, 6Y, and 6K and the cleaning members 5C, 5M, 5Y, and 5K. Transfer brushes 11C, 11M, 11Y, and 11K for applying a transfer bias are disposed on a surface (back surface) that is in contact with the back side of the transfer conveyance belt 10 on the photoconductor side. Each of the image forming elements 6C, 6M, 6Y, and 6K is different in the color of the toner inside the developing device, and the others are the same in configuration.

  In the color electrophotographic apparatus having the configuration shown in FIG. 8, the image forming operation is performed as follows. First, in each of the image forming elements 6C, 6M, 6Y, and 6K, the photoreceptors 1C, 1M, 1Y, and 1K are charged by the charging members 2C, 2M, 2Y, and 2K that rotate in the direction of the arrow (the direction along with the photoreceptor). Next, an electrostatic latent image corresponding to each color image to be created is formed by laser beams 3C, 3M, 3Y, and 3K at an exposure unit (not shown) arranged outside the photoreceptor. Next, the latent image is developed by developing members 4C, 4M, 4Y, and 4K to form a toner image. The developing members 4C, 4M, 4Y, and 4K are developing members that perform development with toners of C (cyan), M (magenta), Y (yellow), and K (black), respectively, and the four photosensitive members 1C, 1M, and 1Y. , 1K toner images of each color are superimposed on the transfer paper. The transfer paper 7 is sent out from the tray by a paper feed roller 8, temporarily stopped by a pair of registration rollers 9, and sent to the transfer conveyance belt 10 in synchronism with the image formation on the photosensitive member. The transfer paper 7 held on the transfer conveyance belt 10 is conveyed, and the toner images of the respective colors are transferred at the contact positions (transfer portions) with the photoconductors 1C, 1M, 1Y, 1K. The toner image on the photoconductor is transferred onto the transfer paper 7 by an electric field formed from a potential difference between the transfer bias applied to the transfer brushes 11C, 11M, 11Y, and 11K and the photoconductors 1C, 1M, 1Y, and 1K. The Then, the recording paper 7 on which the four color toner images are passed through the four transfer portions is conveyed to the fixing device 12, where the toner is fixed, and is discharged to a paper discharge portion (not shown). Further, the residual toner remaining on the photoreceptors 1C, 1M, 1Y, and 1K without being transferred by the transfer unit is collected by the cleaning devices 5C, 5M, 5Y, and 5K. In the example of FIG. 8, the image forming elements are arranged in the order of C (cyan), M (magenta), Y (yellow), and K (black) from the upstream side to the downstream side in the transfer paper conveyance direction. However, it is not limited to this order, and the color order is arbitrarily set. Further, when a black-only document is created, it is particularly effective to use the present invention to provide a mechanism for stopping the image forming elements (6C, 6M, 6Y) other than black. Further, although the charging member is in contact with the photosensitive member in FIG. 8, by using a charging mechanism as shown in FIG. 5, an appropriate gap (about 10 to 200 μm) is provided between them. In addition, the wear amount of the both can be reduced, and toner filming on the charging member can be reduced and the toner can be used well.

  The image forming means as described above may be fixedly incorporated in a copying apparatus, facsimile, or printer, but each electrophotographic element may be incorporated in the apparatus in the form of a process cartridge. A process cartridge is a single device (part) that contains a photoconductor and further includes a charging unit, an exposure unit, a developing unit, a transfer unit, a cleaning unit, a neutralizing unit, and the like.

  EXAMPLES Hereinafter, although an Example demonstrates this invention in detail, this invention is not limited to the following Example at all.

-Synthesis of electron transport agents-
The charge transport material represented by the formula (1) used in the present invention has the following structural skeleton.

（式中、Ｒ１、Ｒ２は、それぞれ独立に水素原子、置換又は無置換のアルキル基、置換又は無置換のシクロアルキル基、置換又は無置換のアラルキル基からなる群より選ばれる基を表し、Ｒ３、Ｒ４、Ｒ５、Ｒ６、Ｒ７、Ｒ８、Ｒ９、Ｒ１０はそれぞれ独立に水素原子、ハロゲン原子、シアノ基、ニトロ基、アミノ基、水酸基、置換又は無置換のアルキル基、置換又は無置換のシクロアルキル基、置換又は無置換のアラルキル基からなる群より選ばれる基を表す。）
該置換又は無置換のアルキル基としては、炭素数１乃至２５、好ましくは炭素数１乃至１０の炭素原子を有するアルキル基、具体的には、メチル基、エチル基、ｎ−プロピル基、ｎ−ブチル基、ｎ−ペンチル基、ｎ−ヘキシル基、ｎ−ペプチル基、ｎ−オクチル基、ｎ−ノニル基、ｎ−デシル基といった直鎖状のもの、ｉ―プロピル基、ｓ−ブチル基、ｔ−ブチル基、メチルプロピル基、ジメチルプロピル基、エチルプロピル基、ジエチルプロピル基、メチルブチル基、ジメチルブチル基、メチルペンチル基、ジメチルペンチル基、メチルヘキシル基、ジメチルヘキシル基等の分岐状のもの、アルコキシアルキル基、モノアルキルアミノアルキル基、ジアルキルアミノアルキル基、ハロゲン置換アルキル基、アルキルカルボニルアルキル基、カルボキシアルキル基、アルカノイルオキシアルキル基、アミノアルキル基、エステル化されていてもよいカルボキシル基で置換されたアルキル基、シアノ基で置換されたアルキル基等が例示できる。なお、これらの置換基の置換位置については特に限定されず、上記置換又は無置換のアルキル基の炭素原子の一部がヘテロ原子（Ｎ、Ｏ、Ｓ等）に置換された基も置換されたアルキル基に含まれる。

Wherein R 1 and R 2 each independently represent a group selected from the group consisting of a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted aralkyl group, and R 3 , R4, R5, R6, R7, R8, R9, R10 are each independently a hydrogen atom, a halogen atom, a cyano group, a nitro group, an amino group, a hydroxyl group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group. Represents a group selected from the group consisting of a group, a substituted or unsubstituted aralkyl group.)
The substituted or unsubstituted alkyl group is an alkyl group having 1 to 25 carbon atoms, preferably 1 to 10 carbon atoms, specifically a methyl group, an ethyl group, an n-propyl group, an n- Straight chain such as butyl group, n-pentyl group, n-hexyl group, n-peptyl group, n-octyl group, n-nonyl group, n-decyl group, i-propyl group, s-butyl group, t -Branched group such as butyl group, methylpropyl group, dimethylpropyl group, ethylpropyl group, diethylpropyl group, methylbutyl group, dimethylbutyl group, methylpentyl group, dimethylpentyl group, methylhexyl group, dimethylhexyl group, alkoxy Alkyl group, monoalkylaminoalkyl group, dialkylaminoalkyl group, halogen-substituted alkyl group, alkylcarbonylalkyl group, Carboxymethyl group, alkanoyloxy group, an aminoalkyl group, esterified optionally alkyl group substituted with a carboxyl group which have an alkyl group substituted by a cyano group are exemplified. The substitution position of these substituents is not particularly limited, and a group in which a part of carbon atoms of the substituted or unsubstituted alkyl group is substituted with a hetero atom (N, O, S, etc.) is also substituted. Included in the alkyl group.

  The substituted or unsubstituted cycloalkyl group includes a cycloalkyl ring having 3 to 25 carbon atoms, preferably 3 to 10 carbon atoms, specifically, a homocyclic ring from cyclopropane to cyclodecane, methylcyclo Those having an alkyl substituent such as pentane, dimethylcyclopentane, methylcyclohexane, dimethylcyclohexane, trimethylcyclohexane, tetramethylcyclohexane, ethylcyclohexane, diethylcyclohexane, t-butylcyclohexane, alkoxyalkyl groups, monoalkylaminoalkyl groups, dialkylamino Alkyl group, halogen-substituted alkyl group, alkoxycarbonylalkyl group, carboxyalkyl group, alkanoyloxyalkyl group, aminoalkyl group, halogen atom, amino group, ester Which may be a carboxyl group, a cycloalkyl group substituted by a cyano group and the like. The substitution position of these substituents is not particularly limited, and a group in which a part of carbon atoms of the substituted or unsubstituted cycloalkyl group is substituted with a hetero atom (N, O, S, etc.) is also substituted. Are included in the alkyl group.

  Examples of the substituted or unsubstituted aralkyl group include groups in which an aromatic ring is substituted on the above-described substituted or unsubstituted alkyl group, and an aralkyl group having 6 to 14 carbon atoms is preferable. More specifically, benzyl group, perfluorophenylethyl group, 1-phenylethyl group, 2-phenylethyl group, terphenylethyl group, dimethylphenylethyl group, diethylphenylethyl group, t-butylphenylethyl group, 3- Examples thereof include a phenylpropyl group, a 4-phenylbutyl group, a 5-phenylpentyl group, a 6-phenylhexyl group, a benzhydryl group, and a trityl group.

  More specifically, electron transport materials 1 to 3 represented by the following formulas (2) to (4) can be obtained, but are preferable in terms of high quality images. In the formula, Me represents a methyl group.

該式（１）で表される電子輸送物質の製造方法としては、下記の方法が例示できる。ナフタレンカルボン酸若しくはその無水物をアミン類と反応させ、モノイミド化する方法、ナフタレンカルボン酸若しくはその無水物を緩衝液によりpＨ調整してジアミン類と反応させる方法等により得られる。モノイミド化は無溶媒、若しくは溶媒存在下でおこなう。溶媒としては特に制限はないが、ベンゼン、トルエン、キシレン、クロロナフタレン、酢酸、ピリジン、メチルピリジン、ジメチルホルムアミド、ジメチルアセトアミド、ジメチルエチレンウレア、ジメチルスルホキサイド等原料や生成物と反応せず５０℃乃至２５０℃の温度で反応させられるものを用いるとよい。pH調整には水酸化リチウム、水酸化カリウム等の塩基性水溶液をリン酸等の酸との混合により作製した緩衝液を用いる。カルボン酸とアミン類やジアミン類とを反応させて得られたカルボン酸誘導体脱水反応は無溶媒、若しくは溶媒存在下でおこなう。溶媒としては特に制限は無いがベンゼン、トルエン、クロロナフタレン、ブロモナフタレン、無水酢酸等原料や生成物と反応せず５０℃乃至２５０℃の温度で反応させられるものを用いるとよい。いずれの反応も、無触媒若しくは触媒存在下でおこなってよく、特に限定されないが例えばモレキュラーシーブスやベンゼンスルホン酸やp-トルエンスルホン酸等を脱水剤として用いることが例示できる。

Examples of the method for producing the electron transport material represented by the formula (1) include the following methods. It can be obtained by reacting naphthalenecarboxylic acid or its anhydride with amines to monoimidize, adjusting the pH of naphthalenecarboxylic acid or its anhydride with a buffer and reacting with diamines, and the like. Monoimidization is carried out without solvent or in the presence of a solvent. The solvent is not particularly limited, but it does not react with raw materials or products such as benzene, toluene, xylene, chloronaphthalene, acetic acid, pyridine, methylpyridine, dimethylformamide, dimethylacetamide, dimethylethyleneurea, dimethylsulfoxide, and the like. It is good to use what can be made to react at the temperature of thru | or 250 degreeC. For pH adjustment, a buffer solution prepared by mixing a basic aqueous solution such as lithium hydroxide or potassium hydroxide with an acid such as phosphoric acid is used. Carboxylic acid derivative dehydration reaction obtained by reacting carboxylic acid with amines or diamines is carried out in the absence of a solvent or in the presence of a solvent. Although there is no restriction | limiting in particular as a solvent, It is good to use what reacts at the temperature of 50 to 250 degreeC, without reacting with raw materials and products, such as benzene, toluene, chloronaphthalene, bromonaphthalene, and acetic anhydride. Any reaction may be carried out without a catalyst or in the presence of a catalyst, and is not particularly limited. For example, molecular sieves, benzenesulfonic acid, p-toluenesulfonic acid and the like can be used as a dehydrating agent.

  The electron transport material represented by the above formula (2) was produced by the following method.

First Step: A 200 ml four-necked flask was charged with 5.0 g (18.6 mmol) of 1,4,5,8-naphthalenetetracarboxylic dianhydride and 50 ml of DMF and heated to reflux. To this, a mixture of 2.14 g (18.6 mmol) of 2-aminoheptane and 25 ml of DMF was added dropwise with stirring. After completion of dropping, the mixture was heated to reflux for 6 hours. After completion of the reaction, the container was cooled and concentrated under reduced pressure. Toluene was added to the residue, and the residue was purified by silica gel column chromatography. Furthermore, the recovered product was recrystallized from toluene / hexane to obtain 2.14 g of monoimide A (yield 31.5%).

Second Step A 100 ml four-necked flask was charged with 2.0 g (5.47 mmol) of monoimide A, 0.137 g (2.73 mmol) of hydrazine monohydrate, 10 mg of p-toluenesulfonic acid, and 50 ml of toluene and heated to reflux for 5 hours. . After completion of the reaction, the container was cooled and concentrated under reduced pressure. The residue was purified by silica gel column chromatography. Further, the recovered product was recrystallized with toluene / ethyl acetate to obtain 0.668 g (yield 33.7%) of the electron transport material 1 represented by the formula (2). In mass spectrometry (FD-MS), a peak of M / z = 726 was observed and identified as a target product. In the elemental analysis, calculated values were 69.41% carbon, 5.27% hydrogen, and 7.71% nitrogen, and the measured values were 69.52% carbon, 5.09% hydrogen, and 7.93% nitrogen.

  Moreover, the electron transport material represented by the above formula (3) was produced by the following method.

First step In a 200 ml four-necked flask, 10 g (37.3 mmol) of 1,4,5,8-naphthalenetetracarboxylic dianhydride, 0.931 g (18.6 mmol) of hydrazine monohydrate, 20 mg of p-toluenesulfonic acid, toluene 100 ml was added and heated to reflux for 5 hours. After completion of the reaction, the container was cooled and concentrated under reduced pressure. The residue was purified by silica gel column chromatography. The recovered product was recrystallized from toluene / ethyl acetate to obtain 2.84 g of dimer C (yield 28.7%).

Second Step In a 100 ml four-necked flask, 2.5 g (4.67 mmol) of both-bodies C and 30 ml of DMF were placed and heated to reflux. To this, a mixture of 0.278 g (4.67 mmol) of 2-aminopropane and 10 ml of DMF was added dropwise with stirring. After completion of dropping, the mixture was heated to reflux for 6 hours. After completion of the reaction, the reaction vessel was cooled and concentrated under reduced pressure. Toluene was added to the residue and the residue was purified by silica gel column chromatography to obtain 0.556 g (yield 38.5%) of monoimide C.

Third Step In a 50 ml four-necked flask, 0.50 g (1.62 mmol) of monoimide C and 10 ml of DMF were placed and heated to reflux. To this, a mixture of 2-aminoheptane 0.186 g (1.62 mmol) and DMF 5 ml was added dropwise with stirring. After completion of dropping, the mixture was heated to reflux for 6 hours. After completion of the reaction, the reaction vessel was cooled and concentrated under reduced pressure. Toluene was added to the residue, and the residue was purified by silica gel column chromatography. Further, the recovered product was recrystallized from toluene / hexane to obtain 0.243 g (yield 22.4%) of the electron transport material 2 represented by the above formula (3). In mass spectrometry (FD-MS), the peak was identified as M / z = 670, and the product was identified as the target product. In the elemental analysis, the calculated values were 68.05% carbon, 4.51% hydrogen, and 8.35% nitrogen, and the measured values were 68.29% carbon, 4.72% hydrogen, and 8.33% nitrogen.

  Moreover, the electron transport material represented by the above formula (4) was produced by the following method.

First Step: A 200 ml four-necked flask was charged with 5.0 g (18.6 mmol) of 1,4,5,8-naphthalenetetracarboxylic dianhydride and 50 ml of DMF and heated to reflux. To this, a mixture of 1.10 g (18.6 mmol) of 2-aminopropane and 25 ml of DMF was added dropwise with stirring. After completion of dropping, the mixture was heated to reflux for 6 hours. After completion of the reaction, the reaction vessel was cooled and concentrated under reduced pressure. Toluene was added to the residue, and the residue was purified by silica gel column chromatography. Further, the recovered product was recrystallized from toluene / hexane to obtain 2.08 g of monoimide B (yield 36.1%).

Second Step A 100 ml four-necked flask was charged with 2.0 g (6.47 mmol) of monoimide B, 0.162 g (3.23 mmol) of hydrazine monohydrate, 10 mg of p-toluenesulfonic acid, and 50 ml of toluene and heated to reflux for 5 hours. . After completion of the reaction, the container was cooled and concentrated under reduced pressure. The residue was purified by silica gel column chromatography. Further, the recovered product was recrystallized from toluene / ethyl acetate to obtain 0.810 g (yield 37.4%) of the electron transport material 3 represented by the above formula (4). In mass spectrometry (FD-MS), the peak of M / z = 614 was observed and identified as the target product. In the elemental analysis, the calculated values were 66.45% carbon, 3.61% hydrogen, and 9.12% nitrogen, and the measured values were 66.28% carbon, 3.45% hydrogen, and 9.33% nitrogen.

-Synthesis of titanyl phthalocyanine crystals-
(Pigment synthesis example 1)
A pigment was prepared according to Japanese Patent Application Laid-Open No. 2001-19871. That is, 29.2 g of 1,3-diiminoisoindoline and 200 ml of sulfolane are mixed, and 20.4 g of titanium tetrabutoxide is added dropwise under a nitrogen stream. After completion of the dropwise addition, the temperature was gradually raised to 180 ° C., and the reaction was carried out by stirring for 5 hours while maintaining the reaction temperature between 170 ° C. and 180 ° C. After the reaction is complete, the mixture is allowed to cool, and then the precipitate is filtered, washed with chloroform until the powder turns blue, then washed several times with methanol, then washed several times with hot water at 80 ° C. and dried. Crude titanyl phthalocyanine was obtained. Crude titanyl phthalocyanine is dissolved in 20 times the amount of concentrated sulfuric acid, added dropwise to 100 times the amount of ice water with stirring, the precipitated crystals are filtered, and then ion-exchanged water (pH: 7.) until the washing solution becomes neutral. 0, specific conductivity: 1.0 μS / cm) Repeated washing with water (pH value of ion-exchanged water after washing was 6.8, specific conductivity was 2.6 μS / cm), wet of titanyl phthalocyanine pigment A cake (water paste) was obtained. 40 g of the obtained wet cake (water paste) was put into 200 g of tetrahydrofuran, stirred for 4 hours, filtered and dried to obtain titanyl phthalocyanine powder. This is designated as Pigment 1.

  The solid content concentration of the wet cake was 15% by mass. The crystal conversion solvent was used in a mass ratio of 33 times that of the wet cake. In addition, the halogen-containing compound is not used for the raw material of the pigment synthesis example 1.

  When the obtained titanyl phthalocyanine powder was subjected to X-ray diffraction spectrum measurement under the following conditions, the Bragg angle 2θ with respect to the Cu—Kα ray (wavelength 1.542１．５) was 27.2 ± 0.2 °, and the maximum peak and the minimum angle 7 A titanyl phthalocyanine powder having a peak at .3 ± 0.2 ° and no peak between the peak at 7.3 ° and the peak at 9.4 ° and no peak at 26.3 ° Was obtained. The result is shown in FIG.

  A part of the water paste obtained in Pigment Synthesis Example 1 was dried at 80 ° C. under reduced pressure (5 mmHg) for 2 days to obtain a low crystalline titanyl phthalocyanine powder. The X-ray diffraction spectrum of the dry powder of water paste is shown in FIG.

<X-ray diffraction spectrum measurement conditions>
X-ray tube: Cu
Voltage: 50kV
Current: 30mA
Scanning speed: 2 ° / min Scanning range: 3 ° to 40 °
Time constant: 2 seconds (Pigment synthesis example 2)
-Synthesis of titanyl phthalocyanine crystals-
According to the method of Pigment Synthesis Example 1, a titanyl phthalocyanine pigment water paste was synthesized, and crystal conversion was performed as follows to obtain phthalocyanine crystals having smaller primary particles than Pigment Synthesis Example 1.

  In accordance with JP 2004-83859 A, Example 1, 400 parts by mass of tetrahydrofuran was added to 60 parts by mass of the water paste before crystal conversion obtained in Pigment Synthesis Example 1, and a homomixer (Kennis, MARKIIf model at room temperature) was added. ) Was vigorously stirred (2000 rpm), and when the dark blue color of the paste changed to light blue (20 minutes after the start of stirring), stirring was stopped and filtration under reduced pressure was immediately performed. The crystals obtained on the filtration device were washed with tetrahydrofuran to obtain a wet cake of pigment. This was dried under reduced pressure (5 mmHg) at 70 ° C. for 2 days to obtain 8.5 parts by mass of titanyl phthalocyanine crystals. This is designated as Pigment 2. The raw material of Pigment Synthesis Example 1 does not use a halogen-containing compound. The solid content concentration of the wet cake was 15% by mass. The crystal conversion solvent was used in a mass ratio of 44 times that of the wet cake.

  A portion of titanyl phthalocyanine (water paste) before crystal conversion prepared in Pigment Synthesis Example 1 is diluted with ion-exchanged water to approximately 1% by mass, and the surface is scooped with a copper net that is conductively treated. The particle size of phthalocyanine was observed with a transmission electron microscope (TEM, Hitachi: H-9000NAR) at a magnification of 75000 times. The average particle size was determined as follows.

  The TEM image observed as described above is taken as a TEM photograph, and 30 titanyl phthalocyanine particles (a shape close to a needle shape) projected are arbitrarily selected, and the size of each major axis is measured. An arithmetic average of the major diameters of the measured 30 individuals was determined and used as the average particle diameter. The average particle size in the water paste in Pigment Synthesis Example 1 determined by the above method was 0.06 μm.

  In addition, the titanyl phthalocyanine crystal after crystal conversion just before filtration in Pigment Synthesis Example 1 and Pigment Synthesis Example 2 was diluted with tetrahydrofuran so as to be about 1% by mass, and observed in the same manner as the above method. The average particle diameter determined as described above is shown in Table 1. In addition, the titanyl phthalocyanine crystals produced in Pigment Synthesis Example 1 and Pigment Synthesis Example 2 did not necessarily have the same shape of all crystals (a shape close to a triangle, a shape close to a square, etc.). For this reason, the calculation was carried out with the length of the largest diagonal line of the crystal as the major axis.

顔料合成例２で作製した顔料２は、先程と同様の方法でＸ線回折スペクトルを測定した。その結果、顔料合成例２で作製した顔料２のＸ線回折スペクトルは、顔料合成例１で作製した顔料１のスペクトルと一致した。

Pigment 2 prepared in Pigment Synthesis Example 2 was measured for an X-ray diffraction spectrum by the same method as described above. As a result, the X-ray diffraction spectrum of Pigment 2 prepared in Pigment Synthesis Example 2 matched the spectrum of Pigment 1 prepared in Pigment Synthesis Example 1.

Example 1
An aluminum cylinder (JIS 1050) having a length of 340 mm and a diameter of 30 mm is used as a conductive support, and this is subjected to the following anodic oxide film treatment, and a photosensitive layer coating solution having the following composition is applied and dried to form a 20 μm photosensitive layer. Thus, a photoreceptor was obtained (referred to as photoreceptor 1).

(Anodized film treatment)
The surface of the support was mirror-polished, degreased and washed with water, and then immersed in an electrolytic bath with a liquid temperature of 20 ° C. and sulfuric acid of 15 vol%, and an anodized film treatment was performed at an electrolysis voltage of 15 V for 30 minutes. Further, after washing with water, sealing treatment was performed with a 7% nickel acetate aqueous solution (50 ° C.). Thereafter, after washing with pure water, a support on which a 6 μm anodic oxide film (alumite) was formed was obtained.

Photosensitive layer coating solution First, 30 parts by weight of pigment 1 previously synthesized as a charge generating material and 970 parts by weight of cyclohexanenone were dispersed in a ball mill apparatus for 2 hours to obtain a charge generating material dispersion. Separately, 340 parts by weight of tetrahydrofuran, 49 parts by weight of Z-type polycarbonate resin (viscosity average molecular weight; 40,000, manufactured by Teijin Chemicals Ltd.), 20 parts by weight of the previously synthesized electron transport agent 1, compound 29 of the following structural formula .5 parts by weight and 0.1 part by weight of silicone oil (KF50-100CS manufactured by Shin-Etsu Chemical Co., Ltd.) are dissolved, and 66.6 parts by weight of the above-described charge generating material dispersion is added and stirred to coat the photosensitive layer. A working liquid was used.

（実施例２）
実施例１において、陽極酸化被膜処理時間を変え、陽極酸化皮膜の膜厚を１μｍに変更した以外は、実施例１と同様に感光体を作製した（感光体２とする）。

(Example 2)
In Example 1, a photoconductor was prepared in the same manner as in Example 1 except that the anodic oxide film treatment time was changed and the thickness of the anodic oxide film was changed to 1 μm (referred to as photoconductor 2).

(Example 3)
In Example 1, a photoconductor was prepared in the same manner as in Example 1 except that the anodic oxide film treatment time was changed and the thickness of the anodic oxide film was changed to 15 μm (referred to as photoconductor 3).

Example 4
In Example 1, a photoconductor was prepared in the same manner as in Example 1 except that the anodized film treatment time was changed and the film thickness of the anodized film was changed to 18 μm (referred to as photoconductor 4).

(Example 5)
In Example 1, a photoconductor was prepared in the same manner as in Example 1 except that the electron transfer agent 2 was used instead of the used electron transfer agent 1 (referred to as photoconductor 5).

(Example 6)
In Example 1, a photoconductor was prepared in the same manner as in Example 1 except that the electron transfer agent 3 was used instead of the used electron transfer agent 1 (referred to as photoconductor 6).

(Example 7)
A photoconductor was prepared in the same manner as in Example 1 except that the sealing treatment with the nickel acetate aqueous solution was not performed in the anodic oxide coating treatment in Example 1 (referred to as Photoconductor 7).

(Example 8)
A photoconductor was prepared in the same manner as in Example 1 except that Pigment 2 was used instead of Pigment 1 used in the photosensitive layer coating solution of Example 1 (referred to as Photoconductor 8).

(Comparative Example 1)
In Example 1, a photoconductor was prepared in the same manner as in Example 1 except that the anodized film treatment was not performed on the aluminum support (referred to as photoconductor 9).

(Comparative Example 2)
In Example 1, the anodized film treatment was not performed on the aluminum support, an intermediate layer coating solution having the following composition was used, and a 0.3 μm intermediate layer was provided between the conductive support and the photosensitive layer. A photoconductor was prepared in the same manner as in Example 1 (referred to as photoconductor 10).

◎ Intermediate layer coating solution Alcohol-soluble nylon (Toray: Amilan CM8000) 4 parts Methanol 70 parts n-Butanol 30 parts Methanol and butanol were mixed, and alcohol-soluble nylon was dissolved in this to make an intermediate layer coating solution.

(Comparative Example 3)
In Example 1, a photoconductor was prepared in the same manner as in Example 1 except that the electron transfer agent 1 was not used in the photosensitive layer coating solution (referred to as photoconductor 11).

(Comparative Example 4)
In Example 1, a photoconductor was prepared in the same manner as in Example 1 except that a substance having the following structure was used instead of the electron transport agent 1 used (referred to as photoconductor 12).

（比較例５）
実施例１において、使用した電子輸送剤１の代わりに下記構造の物質を用いた以外は、実施例１と同様に感光体を作製した（感光体１３とする）。

(Comparative Example 5)
In Example 1, a photoconductor was prepared in the same manner as in Example 1 except that a substance having the following structure was used instead of the electron transport agent 1 used (referred to as photoconductor 13).

（実施例９）
長さ３４０ｍｍ、直径３０ｍｍのアルミシリンダー（ＪＩＳ１０５０）を導電性支持体とし、これを下記の陽極酸化皮膜処理を行い、下記組成の電荷発生層塗工液、電荷輸送層塗工液を順次塗布、乾燥し、０．３μｍの電荷発生層、２０μｍの電荷輸送層を形成して感光体を得た（感光体１４とする）。

Example 9
An aluminum cylinder (JIS 1050) having a length of 340 mm and a diameter of 30 mm is used as a conductive support, and this is subjected to the following anodic oxide film treatment, and a charge generation layer coating solution and a charge transport layer coating solution having the following composition are sequentially applied. It was dried to form a 0.3 μm charge generation layer and a 20 μm charge transport layer to obtain a photoreceptor (referred to as photoreceptor 14).

(Anodized film treatment)
The surface of the support was mirror-polished, degreased and washed with water, and then immersed in an electrolytic bath with a liquid temperature of 20 ° C. and sulfuric acid of 15 vol%, and an anodized film treatment was performed at an electrolysis voltage of 15 V for 30 minutes. Further, after washing with water, sealing treatment was performed with a 7% nickel acetate aqueous solution (50 ° C.). Thereafter, after washing with pure water, a support on which a 6 μm anodic oxide film (alumite) was formed was obtained.

Charge generation layer coating solution A dispersion having the following composition was prepared by bead milling under the conditions shown below.

Titanyl phthalocyanine pigment prepared in Pigment Synthesis Example 1 15 parts Polyvinyl butyral (manufactured by Sekisui Chemical: BX-1) 10 parts 2-butanone 280 parts Dissolve polyvinyl butyral in a commercially available bead mill disperser using PSZ balls with a diameter of 0.5 mm. All of the 2-butanone and the pigment were added, and the rotor rotation speed was 1200 r. p. m. For 30 minutes to prepare a dispersion. The particle size distribution of the pigment particles in this dispersion was measured by HORIBA, Ltd .: CAPA-700. As a result, the average particle size was 0.30 μm, and the standard deviation was 0.19 μm.

◎ Charge transport layer coating solution Electron transfer agent 1 synthesized earlier 9 parts Z-type polycarbonate resin 10 parts (Teijin Chemicals: Panlite TS2040)
Tetrahydrofuran 120 parts Silicone oil 0.01 parts (KF50-100CS Shin-Etsu Chemical Co., Ltd.)
The Z-type polycarbonate resin was dissolved in tetrahydrofuran, and then the electron transport agent 1 and silicone oil were added in this order, and when the insoluble portion disappeared, the charge transport layer coating solution was obtained.

(Comparative Example 6)
In Example 8, a photoconductor was prepared in the same manner as in Example 8 except that the anodized film treatment was not performed on the aluminum support (referred to as photoconductor 15).

(Comparative Example 7)
A photoconductor was prepared in the same manner as in Example 8 except that a substance having the following structure was used instead of the electron transport agent 1 used in the charge transport layer coating solution in Example 8 (referred to as photoconductor 16).

（比較例８）
実施例８における電荷輸送層塗工液に使用した使用した電子輸送剤１の代わりに、下記構造の物質を用いた以外は実施例８と同様に感光体を作製した（感光体１７とする）。

(Comparative Example 8)
A photoconductor was prepared in the same manner as in Example 8 except that a substance having the following structure was used instead of the electron transport agent 1 used in the charge transport layer coating solution in Example 8 (referred to as photoconductor 17). .

（実施例１０）
以上のように作製した感光体１を図４に示すような画像形成装置に搭載し、画像露光光源を７８０ｎｍの半導体レーザー（ポリゴン・ミラーによる画像書き込み）、帯電部材としてスコロトロン帯電器、転写部材として転写ベルトを用い、除電光源として６５５ｎｍＬＥＤを用いた。試験前のプロセス条件が下記になるように帯電部材への印加バイアス、半導体レーザーの光量を設定し、書き込み率６％のチャート（Ａ４全面に対して、画像面積として６％相当の文字が平均的に書かれている）を用い、連続１万枚印刷を行った。

(Example 10)
The photoconductor 1 produced as described above is mounted on an image forming apparatus as shown in FIG. 4, and an image exposure light source is a semiconductor laser of 780 nm (image writing by a polygon mirror), a scorotron charger as a charging member, and a transfer member A transfer belt was used, and a 655 nm LED was used as a static elimination light source. The application bias to the charging member and the amount of light of the semiconductor laser were set so that the process conditions before the test were as follows, and a chart with a writing rate of 6% (characters equivalent to 6% as an image area on the entire A4 surface were averaged) In this case, 10,000 sheets were printed continuously.

Photoconductor charging potential (unexposed portion potential): + 500V
Development bias: + 350V
Surface potential of exposed area at development site: + 60V
The evaluation was performed by measuring the photosensitive member exposed portion potential before and after printing 10,000 images. As a measuring method, a surface potential meter is mounted at the position of the developing portion shown in FIG. 4, and after charging the photoreceptor to +500 V, solid writing is performed with the semiconductor laser, and the surface potential of the unexposed portion and the exposed portion at the developing portion are measured. The potential was measured. The results are shown in Table 2. Further, after 10,000 sheets, a white solid image was output, and the stain on the background portion was evaluated. The background image evaluation was carried out in 4 stages. Very good ones were indicated by ◎, good ones were indicated by ○, slightly inferior ones by Δ, and very bad ones by x. The results are shown in Table 2.

(Examples 11 to 18, Comparative Examples 9 to 16)
Evaluation was performed in the same manner as in Example 9 except that the photosensitive members 2 to 16 were used instead of the photosensitive member 1 used in Example 9. As process conditions, the photosensitive member charging potential (unexposed portion potential) was fixed at +500 V, and the developing bias was fixed at +350 V. In the initial state of the photoconductor in Example 9, the exposure amount was set to the same light amount as the light amount at which the exposed portion potential became 60 V, and the exposed portion surface potential before and after the fatigue test was measured. The results are shown in Table 2.

（実施例１９）
長さ３４０ｍｍ、直径３０ｍｍのアルミシリンダー（ＪＩＳ１０５０）を導電性支持体とし、これを下記の陽極酸化皮膜処理を行い、下記組成の電荷発生層塗工液、電荷輸送層塗工液を順次塗布、乾燥し、０．３μｍの電荷発生層、２０μｍの電荷輸送層を形成して感光体を得た（感光体１８とする）。

Example 19
An aluminum cylinder (JIS 1050) having a length of 340 mm and a diameter of 30 mm is used as a conductive support, and this is subjected to the following anodic oxide film treatment, and a charge generation layer coating solution and a charge transport layer coating solution having the following composition are sequentially applied. It was dried to form a 0.3 μm charge generation layer and a 20 μm charge transport layer to obtain a photoconductor (referred to as photoconductor 18).

(Anodized film treatment)
The surface of the support was mirror-polished, degreased and washed with water, and then immersed in an electrolytic bath with a liquid temperature of 20 ° C. and sulfuric acid of 15 vol%, and an anodized film treatment was performed at an electrolysis voltage of 15 V for 30 minutes. Further, after washing with water, sealing treatment was performed with a 7% nickel acetate aqueous solution (50 ° C.). Thereafter, after washing with pure water, a support on which a 6 μm anodic oxide film (alumite) was formed was obtained.

Charge generation layer coating solution A dispersion having the following composition was prepared by bead milling under the conditions shown below.

Titanyl phthalocyanine pigment prepared in Pigment Synthesis Example 1 15 parts Polyvinyl butyral (manufactured by Sekisui Chemical: BX-1) 10 parts 2-butanone 280 parts Electron transport agent 1 previously synthesized 1 part Diameter of commercially available bead mill disperser 0.5 mm No. 2 PSZ balls, all of 2-butanone and pigment in which polyvinyl butyral and electron transport agent 1 were dissolved were charged, and the rotor rotation speed was 1200 r. p. m. For 30 minutes to prepare a dispersion.

◎ Charge transport layer coating solution 7 parts of charge transport material with the following structure

Ｚ型ポリカーボネート樹脂 １０部
（帝人化成：パンライトＴＳ２０４０）
テトラヒドロフラン １２０部
シリコーンオイル ０．０１部
（ＫＦ５０−１００ＣＳ 信越化学工業社製）
テトラヒドロフランにＺ型ポリカーボネート樹脂を溶解し、次いで電荷輸送物質、シリコーンオイルの順に加えて、不溶部がなくなった時点で電荷輸送層塗工液とした。

10 parts of Z-type polycarbonate resin (Teijin Chemicals: Panlite TS2040)
Tetrahydrofuran 120 parts Silicone oil 0.01 parts (KF50-100CS Shin-Etsu Chemical Co., Ltd.)
A Z-type polycarbonate resin was dissolved in tetrahydrofuran, and then a charge transport material and silicone oil were added in that order, and when the insoluble portion disappeared, a charge transport layer coating solution was obtained.

(Comparative Example 17)
A photoconductor was prepared in the same manner as in Example 17 except that the electron transfer agent 1 used in the charge generation layer coating solution in Example 17 was not used (referred to as photoconductor 19).

(Example 20)
The photosensitive member 17 produced as described above is mounted on an image forming apparatus as shown in FIG. 4, and an image exposure light source is a semiconductor laser of 780 nm (image writing by a polygon mirror), a scorotron charger as a charging member, and a transfer member. A transfer belt was used, and a 655 nm LED was used as a static elimination light source. The application bias to the charging member and the amount of light of the semiconductor laser were set so that the process conditions before the test were as follows, and a chart with a writing rate of 6% (characters equivalent to 6% as an image area on the entire A4 surface were averaged) In this case, 10,000 sheets were printed continuously.

Photoconductor charging potential (unexposed portion potential): −900 V
Development bias: -650V
Surface potential of exposed area at development site: -110V
Evaluation was performed by measuring the unexposed portion of the photoreceptor before and after printing 10,000 images. As a measuring method, a surface potential meter is mounted at the position of the developing portion shown in FIG. 4, the photosensitive member 17 is fixed to an applied bias charged to −900 V in the initial state, and the surface potential of the unexposed portion at the developing portion is measured. did. At this time, the first and second rounds of the photoreceptor were evaluated. The results are shown in Table 3.

(Comparative Example 18)
Evaluation was performed in the same manner as in Example 18 except that the photoconductor 19 was used instead of the photoconductor 18 used in Example 18. The results are shown in Table 3.

（実施例２１）
先に作製した感光体１を図７に示すようなプロセスカートリッジに装着し、図８に示すようなタンデム型フルカラー画像形成装置に搭載し、画像露光光源を７８０ｎｍの半導体レーザー（ポリゴン・ミラーによる画像書き込み）、帯電部材として図５に示すような非接触ローラー帯電器、転写部材として転写ベルトを用い、除電光源として６５５ｎｍＬＥＤを用いた。試験前のプロセス条件が下記になるように設定し、書き込み率６％のチャート（Ａ４全面に対して、画像面積として６％相当の文字が平均的に書かれている）を用い、連続１万枚印刷を行った。

(Example 21)
The previously prepared photoreceptor 1 is mounted on a process cartridge as shown in FIG. 7, mounted in a tandem type full color image forming apparatus as shown in FIG. 8, and an image exposure light source is a 780 nm semiconductor laser (image by a polygon mirror). Writing), a non-contact roller charger as shown in FIG. 5 was used as a charging member, a transfer belt was used as a transfer member, and a 655 nm LED was used as a charge removal light source. Process conditions before the test were set as follows, and a chart with a writing rate of 6% (characters equivalent to 6% as the image area are written on the entire A4 surface) was continuously 10,000. Sheet printing was performed.

Photoconductor charging potential (unexposed portion potential): + 500V
Development bias: + 350V (negative / positive development)
Surface potential after static elimination (unexposed area of writing light): + 80V
Evaluation was made by measuring the potential of the photosensitive member exposed area before and after printing 10,000 images (black station).
As a measuring method, a surface potentiometer was mounted at the position of the developing portion shown in FIG. 8, the photosensitive member was charged to +500 V, solid writing was performed with the semiconductor laser, and the exposed portion potential at the developing portion was measured.

  Further, after printing 10,000 sheets, an ISO / JIS-SCID image N1 (portrait) was output to evaluate the color color reproducibility. The color reproducibility evaluation was carried out in 4 stages. Very good ones were indicated by ◎, good ones were indicated by ○, slightly inferior ones by Δ, and very bad ones by x.

  Further, after printing 10,000 sheets, a white solid image was output and the background stain was evaluated.

  The results are shown in Table 4.

(Examples 22 to 26, Comparative Examples 19 to 26)
Evaluation was performed in the same manner as in Example 21 except that the photosensitive members 2 to 17 were used instead of the photosensitive member 1 used in Example 21. As process conditions, the photosensitive member charging potential (unexposed portion potential) was fixed at +500 V, and the developing bias was fixed at +350 V. In the initial state of the photoreceptor in Example 19, the exposure amount was set to the same light amount as the light amount at which the exposed portion potential reached 80 V, and the exposed portion surface potential before and after the fatigue test was measured. The results are shown in Table 4.

以上、詳細かつ具体的な発明から明らかなように、本発明によれば、導電性支持体上に少なくとも感光層を有する電子写真感光体であって、該導電性支持体表面が陽極酸化被膜処理された支持体であり、該感光層に式（１）で表される電子輸送剤を有する電子写真用感光体を用いることにより、画像形成装置の繰り返し使用時や、画像形成装置の置かれる環境変動等に対して、感光体の静電特性の変動が少なく、異常画像の発生の少ない電子写真感光体が提供される。

As described above, as is clear from the detailed and specific invention, according to the present invention, an electrophotographic photosensitive member having at least a photosensitive layer on a conductive support, the surface of the conductive support being subjected to an anodic oxide coating treatment. By using an electrophotographic photoreceptor having an electron transporting agent represented by the formula (1) in the photosensitive layer, the image forming apparatus can be used repeatedly or in an environment where the image forming apparatus is placed. An electrophotographic photosensitive member is provided in which the electrostatic characteristics of the photosensitive member are less affected by fluctuations and the like, and the occurrence of abnormal images is reduced.

  Further, by using this electrophotographic photosensitive member, an image forming apparatus and a full-color image forming apparatus that can always output a stable image are provided, and a process cartridge that is highly convenient to handle is provided.

The preferred embodiments of the present invention have been described in detail above, but the present invention is not limited to such specific embodiments, and various modifications and changes can be made within the scope of the gist of the present invention described in the claims. It can be changed.

1 is a cross-sectional view illustrating a configuration of an electrophotographic photosensitive member of the present invention. It is sectional drawing which shows another structural example of the electrophotographic photoreceptor of this invention. It is sectional drawing showing another structure of this invention. 1 is a schematic view of an image forming process and an image forming apparatus of the present invention. It is a figure which shows an example of the proximity charging mechanism which has arrange | positioned the gap formation member in the charging member side. It is a figure which shows another example of the electrophotographic process of this invention. It is the schematic of the process cartridge of this invention. 1 is a schematic view of a tandem full-color electrophotographic apparatus of the present invention. 2 is an X-ray diffraction spectrum of a titanyl phthalocyanine powder of synthetic pigment 1. FIG. 2 is an X-ray diffraction spectrum of a low crystalline titanyl phthalocyanine powder of synthetic pigment 1. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 31 Conductive support body 32 Anodized film 33 Photosensitive layer 35 Charge generation layer 37 Charge transport layer 39 Protective layer Fig. 1 Photoconductor Fig. 4 2 Static elimination lamp Fig. 4 3 Charging roller Fig. 4 5 Image exposure unit Fig. 4 6 Developing unit 7 in FIG. 4 Charger before transfer 8 in FIG. 4 Registration roller 9 in FIG. 4 Transfer paper 10 in FIG. 4 10 Transfer charger 11 in FIG. 4 12 Separation charger in FIG. 4 13 Separation claw 13 in FIG. 14 Fur brush 15 in FIG. 4 1 cleaning blade in FIG. 5 3 in FIG. 5 charging roller 21 in FIG. 5 21 gap forming member 22 in FIG. 5 23 in metal shaft 23 in image forming area 24 in FIG. 5 non-image forming area Photoconductor 21 in FIG. 6 22a Drive roller in FIG. 6 22b Drive roller in FIG. 6 23 in FIG. 6 Charging charger in FIG. 6 Image exposure source in FIG. 6 25 in FIG. 6 Fig. 6 26 Pre-cleaning exposure Fig. 6 27 Cleaning brush Fig. 6 28 Neutralizing light source Fig. 1 1 Photoconductor Fig. 7 3 Charging roller Fig. 5 Image exposure section 15 Fig. 7 15 Cleaning brush Fig. 7 Development Roller 17 in FIG. 7 Transfer roller 1C, 1M, 1Y, 1K in FIG. 8 2C, 2M, 2Y, 2K charging member in FIG. 8 3C, 3M, 3Y, 3K laser light in FIG. 8 4C, 4M in FIG. 4Y, 4K Developing member 5C, 5M, 5Y, 5K Cleaning member in FIG. 8 6C, 6M, 6Y, 6K Image forming element in FIG. 8 10 Transfer conveying belt in FIG. 8 11C, 11M, 11Y, 11K Transfer brush in FIG. 8-12 Fixing device

Claims (15)

An electrophotographic photosensitive member having at least a photosensitive layer on a conductive support, the surface of the conductive support being anodized, and represented by the following formula (1) on the photosensitive layer: An electrophotographic photoreceptor comprising an electron transport agent.

Wherein R 1 and R 2 each independently represent a group selected from the group consisting of a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted aralkyl group, and R 3 , R4, R5, R6, R7, R8, R9, R10 are each independently a hydrogen atom, a halogen atom, a cyano group, a nitro group, an amino group, a hydroxyl group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group. Represents a group selected from the group consisting of a group, a substituted or unsubstituted aralkyl group.)   2. The electrophotographic photosensitive member according to claim 1, wherein the anodized film is alumite.   The electrophotographic photosensitive member according to claim 2, wherein the alumite is subjected to a sealing treatment after the anodized film treatment.   4. The electrophotographic photosensitive member according to claim 1, wherein the alumite has a thickness of 1 μm to 15 μm.   The charge generating material contained in the photosensitive layer is titanyl phthalocyanine having a maximum diffraction peak at 27.2 ° as a diffraction peak (± 0.2 °) with a Bragg angle 2θ with respect to the characteristic X-ray of CuKα. The electrophotographic photosensitive member according to any one of claims 1 to 4.   The charge generating material contained in the photosensitive layer has a maximum diffraction peak at 27.2 ° as a diffraction peak (± 0.2 °) with a Bragg angle 2θ with respect to the characteristic X-ray of CuKα, and further 9.4 °. , 9.6 °, 24.0 °, and the lowest angle diffraction peak at 7.3 °, the 7.3 ° peak and the 9.4 ° peak 5. The electrophotographic photosensitive member according to claim 1, wherein the electrophotographic photosensitive member is a titanyl phthalocyanine crystal having no peak in between and no peak at 26.3 °.   The electrophotographic photosensitive member according to claim 6, wherein the average particle size of the titanyl phthalocyanine is 0.25 μm or less.   An electrophotographic method in which at least charging, image exposure, development, and transfer are repeated on an electrophotographic photosensitive member, wherein the electrophotographic photosensitive member is the electrophotographic photosensitive member according to any one of claims 1 to 7. An electrophotographic method characterized by the above.   9. The electrophotographic method according to claim 8, wherein charging is applied to the photosensitive member by applying a charging member while superimposing alternating current.   10. The electrophotographic method according to claim 8, wherein the charging unit is a charging member disposed in contact with or close to the photosensitive member.   An electrophotographic apparatus comprising at least a charging unit, an image exposing unit, a developing unit, a transferring unit, and an electrophotographic photosensitive member, wherein the electrophotographic photosensitive member is according to any one of claims 1 to 7. An image forming apparatus which is an electrophotographic photosensitive member.   At least a photosensitive member, a charging device that uniformly charges the surface of the photosensitive member, an image exposure device that forms an electrostatic latent image by performing image exposure after uniform charging, and develops toner on the electrostatic latent image A full color image forming apparatus comprising a developing device and a plurality of image forming elements arranged thereon, wherein the electrophotographic photosensitive member according to any one of claims 1 to 7 is mounted. apparatus.   At least an electrophotographic photosensitive member that can be attached to and detached from the apparatus main body and is rotated or rotated, a developing unit that develops a latent image formed on the electrophotographic photosensitive member, and the surface of the image carrier after image transfer A process cartridge for an image forming apparatus having a cleaning unit for cleaning the surface of the electrophotographic photosensitive member, wherein the electrophotographic photosensitive member is the electrophotographic photosensitive member according to any one of claims 1 to 7. Process cartridge.   An image forming apparatus comprising the process cartridge according to claim 13.   A full-color image forming apparatus, wherein the process cartridge according to claim 13 is mounted.

Images