JP5147274B2 - Novel imide compound and electrophotographic photosensitive member, process cartridge and electrophotographic apparatus using the same - Google Patents

Description

  The present invention relates to a novel imide compound, an electrophotographic photoreceptor using the same, a process cartridge, and an electrophotographic apparatus, and more specifically, an electrophotographic photoreceptor having a novel imide compound in an intermediate layer, and the electrophotographic photoreceptor. The present invention relates to a process cartridge and an electrophotographic apparatus.

  Electrophotographic photoreceptor materials include hole transport materials that transport holes, electron transport materials that transport electrons, charge generation materials that generate charges, and binder resins that form them to give mechanical / electrical strength, etc. In addition, various additives that impart various other properties are known.

  Among them, electron transport materials are also required for making various electro devices such as organic solar cells and organic light-emitting elements, but are often put into practical use because they have various difficulties such as solubility and stability. There are fewer examples than hole transport materials.

  Among them, 2-nitro-9-fluorenone, 2,7-dinitro-9-fluorenone, 2,4,7-trinitro-9-fluorenone, 2,4,5,7-tetranitro-9-fluorenone, 2-nitro Benzothiophene and the like are known. Further, 2,4,8-trinitrothioxanthone, dinitroanthracene, dinitroacridine, dinitroanthraquinone, naphthoquinones, 3,5-dimethyl-3 ', 5'-di-t-butyldiphenoquinone and the like are known. Among them, an imide compound having a naphthalenetetracarboxylic acid diimide skeleton is known as an organic electronic material such as an organic light emitting device (for example, Patent Document 1) and an electrochromic element (for example, Patent Document 2). In addition, an imide compound having a naphthalenetetracarboxylic acid diimide skeleton is one of promising electron transport materials, and is widely known as an electrophotographic material (for example, Patent Document 3 and Patent Document 4).

  An electrophotographic photosensitive member is required to have high image quality without sensitivity, electrical characteristics, optical characteristics and image defects according to the applied electrophotographic process, and in any environment of low temperature and low humidity to high temperature and high humidity. It is required to have environmental stability so that the characteristics are sufficiently exhibited.

  Typical image defects include image streaks, black spots on white portions, white spots on black portions, ground fog on white portions, and the like. Furthermore, when exposure is performed using a laser diode such as a digital copying machine or a laser beam printer as a light source, there may be interference fringes generated due to factors such as the surface shape of the support and the film thickness unevenness of the photoreceptor.

  An intermediate layer is used as necessary as a method for preventing the image defects. The intermediate layer is required to have an electrical blocking function so that charge injection does not occur from the support when a voltage is applied to the electrophotographic photosensitive member. If there is charge injection from the support, the chargeability, image contrast, and reversal development method cause black spots and fogging on a white background, resulting in a significant decrease in image quality.

  On the other hand, if the electrical resistance of the intermediate layer is too high, the charge generated in the photosensitive layer stays inside the photosensitive layer, resulting in an increase in residual potential and potential fluctuation due to repeated use. Therefore, in addition to the electrical blocking function, it is necessary to reduce the electrical resistance value of the intermediate layer to some extent, and the blocking function and electrical resistance characteristics change greatly in any environment from low temperature to low humidity to high temperature and high humidity. Must not.

  Examples of the material for forming the intermediate layer include polyamide (Patent Literature 5, Patent Literature 6 and Patent Literature 7), polyester (Patent Literature 8 and Patent Literature 9), polyurethane (Patent Literature 10 and Patent Literature 11), and casein (Patent Literature 12). ) Etc. are known. Polypeptide (patent document 13), polyvinyl alcohol (patent document 14), polyvinylpyrrolidone (patent document 15), vinyl acetate-ethylene copolymer (patent document 16), maleic anhydride ester polymer (patent document 17), etc. It has been known. Also known are polyvinyl butyral (Patent Literature 18 and Patent Literature 19), quaternary ammonium salt-containing polymers (Patent Literature 20 and Patent Literature 21), and the like.

  However, these resins often have high hygroscopicity, and the resistance value changes greatly depending on the humidity of the outside world. When an intermediate layer is formed of the resin alone, the residual potential increases, in low temperature / low humidity, high temperature / high humidity environments. Variations in the electrical characteristics of the photoreceptor occurred, and image defects were not sufficiently improved.

  Therefore, a proposal has been made to use a crosslinkable resin for the intermediate layer as a resin whose resistance value is less dependent on environmental changes.

  For example, an example using a melamine resin (Patent Literature 22, Patent Literature 23 and Patent Literature 24), an example using a phenol resin (Patent Literature 25), an example using an epoxy resin (Japanese Patent Laid-Open No. 52-121325), and the like are known. ing. However, according to the authors' study, these methods also have a relatively small resistance dependency on the environment, but the absolute value is high, causing a rise in residual potential, and the environment dependency becomes large during repeated use. Problems occur.

  In addition, an intermediate layer having a polynaphthylimide resin has been proposed (for example, Patent Document 27), and stable potential characteristics are obtained from low temperature and low humidity to high temperature and high humidity. An intermediate layer containing naphthalenetetracarboxylic acid diimide containing a carboxylic acid ester has been proposed (for example, Patent Document 28), and an intermediate layer obtained by polymerizing an electron transport material having a non-hydrolyzable polymerizable group has been proposed. (For example, Patent Document 29).

  However, the development of today's electrophotographic technology is remarkable, and very advanced technology is required for the characteristics required for electrophotographic photoreceptors. For example, process speeds are increasing year by year, and charging characteristics, sensitivity, durability stability, and the like have been demanded. In particular, in recent years, high-quality images have been avoided as represented by colorization, and black-and-white images that have been character-centered have become more and more halftone images and solid images represented by photographs. Their image quality is increasing year by year. Further, since the frequency of continuous printing of a plurality of sheets is increasing, not only the quality of each print image is high, but also the uniformity of all images is important. With the recent improvement in image quality and durability, it has been necessary to solve the problems of potential fluctuations and image defects under various environments in order to provide a more excellent electrophotographic photosensitive member.

  At present, an electrophotographic apparatus that employs a contact charging method in which a voltage is directly applied to a charging member arranged in contact with the electrophotographic photosensitive member to charge the electrophotographic photosensitive member is widely used.

In particular, there is a method of charging the electrophotographic photosensitive member by bringing a roller-shaped charging member as a charging member into contact with the surface of the electrophotographic photosensitive member and applying a superimposed voltage of a DC voltage and an AC voltage or applying only a DC voltage. It has become mainstream. When DC voltage and AC voltage are superposed, a DC power supply and an AC power supply are required, which increases the cost of the device itself, increases the size of the device compared to the DC voltage alone, and consumes a large amount of AC current to charge the charging member. In addition, there are disadvantages such as a decrease in the durability of the photoreceptor. Therefore, in view of device cost reduction, device size reduction, and high durability, it can be said that a method of applying only a DC voltage (DC charging method) is more preferable. However, in the electrophotographic apparatus using the DC charging method, the charging uniformity of the surface potential of the electrophotographic photosensitive member at the time of charging is inferior to the case where the DC voltage and the AC voltage are superimposed. For this reason, there is a problem of a stripe-like defective image (charging stripe) in the longitudinal direction of the electrophotographic photosensitive member caused by uneven charging in a halftone image or the like.
JP-A-4-212286 JP-A-2-189524 JP 11-343291 A U.S. Pat. No. 4,442,193 JP-A-46-47344 JP-A-52-25638 JP 58-95351 A JP-A-52-20836 JP 54-26738 A JP-A 49-10044 JP-A-53-89435 JP-A-55-103556 JP 53-48523 A JP 52-100240 A JP-A-48-30936 JP-A-48-261141 JP 52-10138 A JP-A-57-90639 JP 58-106549 A JP 51-126149 A JP-A-56-60448 JP-A-4-22966 Japanese Examined Patent Publication No. 4-31576 Japanese Patent Publication No. 4-31577 JP-A-3-48256 JP 52-121325 A JP 2003-345044 A JP-A-5-27469 JP 2003-330209 A

  SUMMARY OF THE INVENTION An object of the present invention is to provide an electrophotographic photosensitive member that does not cause repelling or unevenness of a photosensitive layer, can suppress charging stripes and potential variation under low temperature and low humidity, and can continuously form excellent images.

  Another object of the present invention is to provide a process cartridge and an electrophotographic apparatus provided with the electrophotographic photosensitive member.

  As a result of investigating a compound capable of achieving both improvement in coating properties and both charging stripes and potential fluctuations at a high level, the present inventors have succeeded in synthesizing a novel imide compound described below. It has been found that this imide compound has the above characteristics.

That is, the present invention has the following formula (1) -1 or (1) - imide compound represented by 3.

The present invention also provides an electrophotographic photosensitive member having a conductive support, an intermediate layer on the conductive support, and a photosensitive layer on the intermediate layer, wherein the intermediate layer has the formula (1)- 1. An electrophotographic photosensitive member comprising an imide compound represented by 1 or (1) -3 .

  The present invention also provides a process cartridge and an electrophotographic apparatus provided with the electrophotographic photosensitive member.

  The reason why the photoreceptor containing the imide compound of the present invention has such excellent characteristics is not clear, but the structure of the present invention exhibits particularly excellent characteristics among various imide compounds. It is expected that. The arrangement of substituents is considered important and is the result of some interaction between the imide compound and the binder resin and the charge generation layer in contact with the interface.

  Asymmetries with greatly different structures of the two imidized substituents show excellent properties, in particular, one is an alkyl-substituted phenyl at the two o positions relative to the imide and the other is an alkyl with a hydroxyl group. The imide compound showed excellent properties.

  The novel imide compound of the present invention enables an electrophotographic photoreceptor capable of continuously forming excellent images without causing repelling or unevenness of the photosensitive layer, suppressing charging stripes and potential fluctuations under low temperature and low humidity. . The present invention also enables a process cartridge and an electrophotographic apparatus provided with the electrophotographic photosensitive member.

  Hereinafter, the electrophotographic photoreceptor of the present invention will be described in detail.

  Examples of the conductive support used in the present invention include metals or alloys such as aluminum, nickel, copper, gold, and iron, polyester, polycarbonate, and polyimide. In addition, a thin film of a conductive material such as indium oxide or tin oxide formed on a metal such as aluminum, silver or gold on an insulating support such as glass, carbon or conductive filler is dispersed in the resin to make it conductive. Examples can be given. For the surface of these supports, a support that has been subjected to an electrochemical treatment such as anodization can be used in order to improve electrical characteristics or adhesion. Also, the surface of the conductive support is chemically treated with a solution obtained by dissolving a metal salt compound or a fluorine compound metal salt in an acidic aqueous solution mainly composed of alkali phosphate or phosphoric acid or tannic acid. It can also be used.

  In addition, when the electrophotographic photosensitive member is used in a printer using a single wavelength laser beam or the like, the surface of the conductive support needs to be appropriately roughened in order to suppress interference fringes. is there. Specifically, a support having a surface of the support subjected to honing, blasting, cutting, electropolishing, or the like, or a support having a conductive film made of a conductive metal oxide and a binder resin on aluminum and an aluminum alloy is provided. It is necessary to use it.

  As the honing treatment, there are dry and wet treatment methods, and any of them may be used. The wet honing process is a method in which a powdered abrasive is suspended in a liquid such as water and sprayed onto the surface of the support at a high speed to roughen the surface. The surface roughness is the spray pressure, speed, and amount of abrasive. It can be controlled by the type, shape, size, hardness, specific gravity, suspension temperature and the like. Similarly, the dry honing process is a method in which an abrasive is sprayed onto the surface of the conductive support with air at a high speed to roughen the surface, and the surface roughness can be controlled in the same manner as the wet honing process. Examples of the abrasive used in these wet or dry honing processes include particles such as silicon carbide, alumina, iron and glass beads.

In the method of applying a conductive film made of a conductive metal oxide and a binder resin to an aluminum or aluminum alloy support to make a conductive support, a powder made of conductive fine particles is used as a filler in the conductive film. contains. This method has the effect of dispersing the fine particles in the film to diffusely reflect the laser beam to prevent interference fringes and conceal the scratches and protrusions of the support before coating. Titanium oxide, barium sulfate, or the like is used for the fine particles. If necessary, a conductive coating layer is provided on the fine particles with tin oxide or the like, so that a specific resistance suitable as a filler is obtained. The specific resistance of the conductive fine particle powder is preferably 0.1 Ω · cm to 1000 Ω · cm, more preferably 1 Ω · cm to 1000 Ω · cm. The specific resistance of the powder was measured using a resistance measuring device Loresta AP manufactured by Mitsubishi Chemical Corporation. The powder to be measured was hardened at a pressure of 49 MPa (500 kg / cm ² ) and mounted as a coin-shaped sample on the measuring device. The average particle size of the fine particles is preferably 0.05 μm or more and 1.0 μm or less, and more preferably 0.07 μm or more and 0.7 μm or less. The average particle diameter of the fine particles is a value measured by a centrifugal sedimentation method. The content of the filler is preferably 1.0% by mass or more and 90% by mass or less, and more preferably 5.0% by mass or more and 80% by mass or less with respect to the conductive film layer. The coating layer may contain fluorine or antimony as necessary.

  As the binder resin used for the conductive film, for example, phenol resin, polyurethane, polyamide, polyimide, polyamideimide, polyamic acid, polyvinyl acetal, epoxy resin, acrylic resin, melamine resin, or polyester is preferable. These resins may be used alone or in combination of two or more. These resins have good adhesion to the support, improve the dispersibility of the filler used, and have good solvent resistance after film formation. Among the above resins, phenol resin, polyurethane and polyamic acid are particularly preferable.

The conductive film can be formed, for example, by dipping or solvent application with a Meyer bar or the like. The thickness of the conductive film is preferably 0.1 μm or more and 30 μm or less, and more preferably 0.5 μm or more and 20 μm or less. The volume resistivity of the conductive film is preferably 10 ¹³ Ω · cm or less, more preferably 10 ¹² Ω · cm or less and 10 ⁵ Ω · cm or more. In the present invention, the volume resistivity is obtained by applying a conductive film to be measured on an aluminum plate, further forming a gold thin film on the film, and calculating the current value flowing between both electrodes of the aluminum plate and the gold thin film as pA. It was determined by measuring with a meter. The conductive film may contain a filler made of powder such as zinc oxide or titanium oxide in addition to the powder made of barium sulfate fine particles having a coating layer. Furthermore, a leveling agent may be added to enhance the surface property.

  The shape of the conductive support is not particularly limited, and a plate shape, a drum shape or a belt shape is used as necessary.

  The intermediate layer used in the present invention may contain a binder resin having an adhesive function and a barrier function, if necessary. Examples of the binder resin include thermoplastic resins such as polyamide, polyvinyl alcohol, polyethylene oxide, ethyl cellulose, casein, polyurethane, and polyether urethane. Moreover, thermosetting materials, such as a melamine resin, a phenol resin, an alkyd resin, an epoxy resin, a silane coupling agent, and an organometallic complex, are mentioned.

  As the binder resin, a polyamide resin and a resin having a repeating unit unit having an isocyanate group in the alkylene main chain and side chain are particularly preferable. The resin having the repeating unit is preferably a copolymer having a repeating unit represented by the following formula (A) and a vinyl monomer such as styrene, methyl methacrylate or benzyl methacrylate.

(In the formula (A), R ₂₁ represents a hydrogen atom or an optionally substituted alkyl group or aryl group. R ₂₂ represents an alkyl group or ether optionally interrupted by an ether group having 1 or more carbon atoms. R ₂₂ represents an alkyl group, an alkenyl group, a nitro group, a halogen group, or an aryl group which may have a halogen-substituted alkyl group, or R which may be interrupted by a group, or R. ₂₂ represents an aralkyl group which may have an alkyl group, an alkenyl group, a nitro group, a halogen group or a halogen-substituted alkyl group.

  In the resin having the repeating unit represented by the formula (A), the ratio of the repeating unit to the whole resin is preferably 10 mol% or more and 90 mol% or less, and the molecular weight of the resin is preferably 1000 or more and 200000 or less. .

The imide compound of the present invention is an asymmetric imide compound represented by the following formula (1) -1 or (1) -3 .

  In the present invention, the intermediate layer contains one or both of the imide compound and a polymer thereof. The imide compound and the polymer thereof are preferably 5% by mass or more and 95% by mass or less, more preferably 10% by mass or more and 80% by mass or less, and further preferably 30% by mass or more and 70% by mass or less with respect to the entire intermediate layer. is there.

  The above material is applied after being dissolved in a suitable solvent, and the film thickness of the intermediate layer is preferably 0.05 μm or more and 5 μm or less, and particularly preferably 0.3 μm or more and 3 μm or less.

Next, the example of an imide compound is given.

  Examples of charge generating materials used in the present invention include pyrylium dyes, thiopyrylium dyes, phthalocyanine pigments, anthanthrone pigments, dibenzpyrenequinone pigments, pyratron pigments, azo pigments, indigo pigments, quinacridone pigments, etc. Is mentioned. Further, quinocyanine dyes and the like can be mentioned. Examples of the phthalocyanine pigment include metal-free phthalocyanine, oxytitanium phthalocyanine, hydroxyphthalocyanine, and gallium halide phthalocyanine such as chlorogallium. In particular, metal phthalocyanine pigments are preferable, and among them, oxytitanium phthalocyanine crystal, chlorogallium phthalocyanine crystal, dichlorotin phthalocyanine crystal, and hydroxygallium phthalocyanine crystal are preferable. Furthermore, hydroxygallium phthalocyanine crystals are particularly preferred. The oxytitanium phthalocyanine crystal is preferably an oxytitanium phthalocyanine crystal having strong peaks at 9.0 °, 14.2 °, 23.9 °, and 27.1 ° of the Bragg angles (2θ ± 0.2 °) in X-ray diffraction using CuKα as a radiation source. Further, oxytitanium phthalocyanine crystals having strong peaks at Bragg angles (2θ ± 0.2 °) of 9.5 °, 9.7 °, 11.7 °, 15.0 °, 23.5 °, 24.1 ° and 27.3 ° are preferable. The chlorogallium phthalocyanine crystal is preferably a chlorogallium phthalocyanine crystal having strong diffraction peaks at Bragg angles (2θ ± 0.2 °) of 7.4 °, 16.6 °, 25.5 and 28.2 ° in X-ray diffraction using CuKα as a radiation source. Further, chlorogallium phthalocyanine crystals having strong diffraction peaks at Bragg angles (2θ ± 0.2 °) of 6.8 °, 17.3 °, 23.6 ° and 26.9 ° are preferable. Further, chlorogallium phthalocyanine crystals having strong diffraction peaks at Bragg angles (2θ ± 0.2 °) of 8.7 to 9.2 °, 17.6 °, 24.0 °, 27.4 ° and 28.8 ° are preferable. The dichlorotin phthalocyanine crystal has strong diffraction peaks at 8.3 °, 12.2 °, 13.7 °, 15.9 °, 18.9 ° and 28.2 ° Bragg angles (2θ ± 0.2 °) in X-ray diffraction using CuKα as a radiation source. Dichlorotin phthalocyanine crystals are preferred. Further, dichlorotin phthalocyanine crystals having strong diffraction peaks at 8.5, 11.2 °, 14.5 °, and 27.2 ° of the Bragg angle (2θ ± 0.2 °) are preferable. Further, dichlorotin phthalocyanine crystals having strong diffraction peaks at Bragg angles (2θ ± 0.2 °) of 8.7 °, 9.9 °, 10.9 °, 13.1 °, 15.2 °, 16.3 °, 17.4 °, 21.9 °, and 25.5 ° are preferable. Further, dichlorotin phthalocyanine crystals having strong diffraction peaks at Bragg angles (2θ ± 0.2 °) of 9.2 °, 12.2 °, 13.4 °, 14.6 °, 17.0 °, and 25.3 ° are preferable. The hydroxygallium phthalocyanine crystal is preferably a hydroxygallium phthalocyanine crystal having strong diffraction peaks at Bragg angles (2θ ± 0.2 °) of 7.3 °, 24.9 °, and 28.1 ° in X-ray diffraction using CuKα as a radiation source. Further, hydroxygallium phthalocyanine crystals having strong diffraction peaks at Bragg angles (2θ ± 0.2 °) of 7.5 °, 9.9 °, 12.5 °, 16.3 °, 18.6 °, 25.1 °, and 28.3 ° are preferable.

  The charge generation layer may contain a charge generation material other than the phthalocyanine compound up to 50% by mass with respect to the total charge generation material. Examples thereof include selenium-tellurium, pyrylium, thiapyrylium dyes, anthanthrone, dibenzpyrenequinone, trisazo, cyanine, disazo, monoazo, indigo, quinacridone, and asymmetric quinocyanine pigments.

  The charge generation layer comprises a homogenizer, an ultrasonic dispersion, a ball mill, a vibration ball mill, a sand mill, an attritor, a roll mill, or a liquid collision type together with a binder resin and a solvent having a mass ratio of 0.3 to 4 times by weight. Disperse sufficiently using a high-speed disperser. Thereafter, a solution obtained by adding an electron transporting compound to the dispersion is applied and dried.

  Examples of the binder resin include butyral resin, polyester resin, polycarbonate resin, polyarylate resin, polystyrene resin, polyvinyl methacrylate resin, polyvinyl acrylate resin, polyvinyl acetate resin, and polyvinyl chloride resin. Moreover, although a polyamide resin, a polyurethane resin, a silicone resin, an alkyd resin, an epoxy resin, a cellulose resin, a melamine resin, etc. are mentioned, it is not limited to these. In particular, a butyral resin is preferred. The film thickness of the charge generation layer is preferably 5 μm or less, particularly preferably 0.1 μm or more and 2 μm or less.

  A charge transport layer is formed on the charge generation layer. The charge transport layer is mainly formed by applying and drying a paint in which a charge transport material (hole transport material) having a hole transport ability and a binder resin are dissolved in a solvent. Examples of the charge transport material used include triarylamine compounds, hydrazone compounds, stilbene compounds, pyrazoline compounds, oxazole compounds, triallylmethane compounds, and thiazole compounds.

  Examples of the binder resin include polyester resin, polycarbonate resin, polyarylate resin, polystyrene resin, polyvinyl methacrylate resin, polyvinyl acrylate resin, polyamide resin, polyurethane resin, and silicone resin. Moreover, although an alkyd resin, an epoxy resin, a cellulose resin, a melamine resin, etc. are mentioned, when the polyarylate resin which has a structural unit shown by following formula (B) was used, the especially preferable electrical potential fluctuation inhibitory effect was acquired.

  The polyarylate resin having a structural unit represented by the following formula (B) is preferably used alone or mixed with a resin such as a polycarbonate resin, a polyester resin, a polymethacrylic acid ester, a polystyrene resin, an acrylic resin, or a polyamide resin. . Further, it is preferable to use a mixture with an organic photoconductive polymer such as poly-N-vinylcarbazole or polyvinylanthracene.

(In the formula, X ₄₀ represents a carbon atom or a single bond (in which R ₁₅ and R _{16 are} absent), and R ₁₁ to R ₁₄ represent a hydrogen atom, a halogen atom, an optionally substituted alkyl group or an aryl group. R ₁₅ and R ₁₆ represent a hydrogen atom, a halogen atom, an alkyl group which may be substituted, an aryl group, or an alkylidene group formed by combining R ₁₅ and R ₁₆ , and R ₁₇ to R ₂₀ represents a hydrogen atom, a halogen atom, an optionally substituted alkyl group or an aryl group.)

  The weight average molecular weight of the binder resin is preferably 50,000 to 200,000, more preferably 100,000 to 180,000. The weight average molecular weight was determined by measuring the molecular weight distribution using gel permeation chromatography (“HLC-8120” manufactured by Tosoh Corporation) and calculating the polystyrene equivalent.

For the measurement, tetrahydrofuran (THF) was used as a developing solvent, and a 0.1 mass% solution of a resin sample was used as a column with an exclusion limit molecular weight (polystyrene conversion) 4 × 10 ⁶ column (“TSKgel SuperHM-N” manufactured by Tosoh Corporation). )). Further, RI was used as a detector under the conditions of a column temperature of 40 ° C., an injection amount of 20 μl, and a flow rate of 1.0 ml / min.

  The charge transport material is combined with a binder resin having a mass ratio of 0.5 to 2 times, and is applied and dried to form a charge transport layer. The film thickness of the charge transport layer is preferably 5 μm or more and 30 μm or less, and more preferably 8 μm or more and 19 μm or less.

  In addition to the charge transport layer, antioxidants such as hindered phenols and hindered amines, lubricating materials such as silicone oil, silicone oil particles and fluorine atom-containing resin particles, and film strength reinforcing materials such as silicone balls are added. May be. A coating liquid containing these is applied onto the charge generation layer and dried to obtain a charge transport layer.

  In the present invention, a protective layer may be provided on the charge transport layer. Examples of the material constituting the protective layer include polyester, polyacrylate, polyethylene, polystyrene, polybutadiene, polycarbonate, polyamide, polypropylene, polyimide, polyamideimide, polysulfone, and polyacryl ether. Moreover, polyacetal, phenol, acrylic, silicone, epoxy, urea, allyl, alkyd, butyral, phenoxy, phosphazene, acrylic modified epoxy, acrylic modified urethane, acrylic modified polyester resin, and the like can be given. The thickness of the protective layer is preferably 0.2 μm or more and 10 μm or less.

  Each of the above layers contains a lubricant such as polytetrafluoroethylene, polyvinylidene fluoride, fluorine-based graft polymer, silicone-based graft polymer, and fluorine-based block polymer in order to improve cleaning properties and abrasion resistance. May be. Further, a lubricant such as a silicone block polymer and a silicone oil may be contained. Furthermore, an additive such as an antioxidant may be added for the purpose of improving the weather resistance.

  Further, conductive powder such as conductive tin oxide and conductive titanium oxide may be dispersed in the protective layer for the purpose of resistance control.

  FIG. 1 shows a schematic configuration of an electrophotographic apparatus having a process cartridge having the electrophotographic photosensitive member of the present invention.

  In FIG. 1, reference numeral 1 denotes a drum-shaped electrophotographic photosensitive member of the present invention, which is rotationally driven around a shaft 2 in the direction of an arrow at a predetermined peripheral speed. In the rotation process, the electrophotographic photosensitive member 1 is uniformly charged with a predetermined positive or negative potential on its peripheral surface by the charging unit 3, and then from an exposure unit (not shown) such as slit exposure or laser beam scanning exposure. Exposure light 4 is received. In this way, electrostatic latent images are sequentially formed on the peripheral surface of the electrophotographic photosensitive member 1.

  The formed electrostatic latent image is then developed with toner by the developing unit 5, and the developed toner image is transferred between the electrophotographic photosensitive member 1 and the transfer unit 6 from a paper supply unit (not shown). Then, the image is sequentially transferred by the transfer means 6 onto the transfer material taken out in synchronization with the rotation of the paper and fed.

  The transfer material 7 that has received the image transfer is separated from the surface of the electrophotographic photosensitive member, introduced into the image fixing means 8, and subjected to image fixing to be printed out as a copy (copy).

  After the transfer process, the toner remaining on the electrophotographic photosensitive member is removed and collected by the cleaning means 9 to clean the surface of the electrophotographic photosensitive member. Further, there may be a case where static elimination processing is performed by pre-exposure light 10 from pre-exposure means (not shown).

  The charging means 3 may be a scorotron charger or a corotron charger using corona discharge, or a contact type charger using a known form such as a roller shape, a blade shape, or a brush shape.

  In the present invention, a process cartridge may be configured by integrally combining a plurality of components such as the electrophotographic photosensitive member 1, the charging unit 3, the developing unit 5, and the cleaning unit 9 as a process cartridge. Good. The process cartridge may be configured to be detachable from the main body of an electrophotographic apparatus such as a copying machine or a laser beam printer.

  For example, at least one of the charging unit 3, the developing unit 5 and the cleaning unit 9 is integrally supported together with the electrophotographic photosensitive member 1 to form a cartridge, and is detachable from the apparatus main body using guide means such as a rail 12 of the apparatus main body. Process cartridge 11.

  Further, when the electrophotographic apparatus is a copying machine or a printer, the exposure light 4 is a reflected light or transmitted light from the original, or the original is read by a sensor and converted into a signal, and a laser beam performed in accordance with this signal. It is light irradiated by scanning. Further, the light is emitted by driving the LED array, driving the liquid crystal shutter array, or the like performed according to this signal.

  The electrophotographic photosensitive member of the present invention can be applied to general electrophotographic apparatuses such as copying machines, laser printers, LED printers, and liquid crystal shutter printers. Furthermore, the present invention can be widely applied to apparatuses such as a display, recording, light printing, plate making and facsimile using the electrophotographic technology.

  EXAMPLES Next, although an Example demonstrates this invention concretely, this invention is not limited by these Examples. In addition, "part" in an Example represents a mass part.

(Synthesis Example 1)
Under a nitrogen stream, 1,4,5,8-naphthalenetetracarboxylic dianhydride (20 parts) and imidazole (1 part) were mixed, and 2-methyl-6-ethylaniline (50 parts) and 2-amino-1-butanol (7.3) were mixed. Part was added and stirred with heating at 170 ° C. for 3 h. After completion of the reaction, 500 ml of toluene was added and separation and purification were performed by silica gel column chromatography. The obtained brown liquid was heated and cooled to obtain 10 parts of yellowish white crystals.

(MALDI-TOF MS: ultraflex manufactured by Bruker Daltonics Co., Ltd.) (acceleration voltage: 20 kV, mode: Reflector, molecular weight standard product: fullerene C60), when molecular weight was measured by mass spectrometry, 456 was obtained as the peak top value. It was. Moreover, it confirmed that it was an imide compound shown by the said Formula (1) -1 from the infrared absorption spectrum shown in FIG. 2, and the proton NMR shown in FIG .

The infrared absorption spectrum was measured by a KBr tablet method using a Fourier transform infrared spectrophotometer (trade name: Paragon1000) manufactured by PerkinElmer Japan, Inc. at a resolution of 4 cm ⁻¹ , and NMR was performed using R-1100 manufactured by Hitachi, Ltd. : CDCl3, concentration 10%, internal standard TMS

Example 1
An aluminum base pipe (ED pipe) of A3003 obtained by hot extrusion and having an outer diameter of 29.92 mm and a length of 260.5 mm was prepared.

  A solution composed of the following materials was dispersed with a ball mill for about 20 hours to prepare a coating solution for conductive particle resin dispersion layer (the average particle size of the filler contained in this coating solution was 0.22 μm). 120 parts of powder composed of fine particles of barium sulfate having a coating layer formed of tin oxide (coverage: 50 mass%, powder specific resistance: 700 Ω · cm). 70 parts of a resol type phenolic resin (trade name: Bryofen J-325, manufactured by Dainippon Ink & Chemicals, Inc., solid content: 70% by mass). 100 parts of 2-methoxy-1-propanol. The coating solution is applied onto the aluminum base tube by a dip coating method and heated and cured at 140 ° C. for 30 minutes to form a conductive particle resin dispersion layer having a thickness of 15 μm. did.

3 parts of the imide compound represented by the above formula (1) -1 and 7 parts of polyamide resin (Amilan CM8000, manufactured by Toray Industries, Inc.) on the conductive support are 120 parts of butanol, 100 parts of methanol, DMF30. The solution dissolved in the part was applied by a dip coating method. Subsequently, it dried at 90 degreeC for 5 minute (s), and formed the intermediate | middle layer with a film thickness of 0.7 micrometer.

  Next, 350 parts of cyclohexanone was added to the following materials as a charge generation material, dispersed in a sand mill using 1 mmφ glass beads for 3 hours, and diluted with 1200 parts of ethyl acetate. Hydroxygallium phthalocyanine crystal with strong diffraction peaks at Bragg angles (2θ ± 0.2 °) of 7.5 °, 9.9 °, 12.5 °, 16.3 °, 18.6 °, 25.1 ° and 28.3 ° in X-ray diffraction using CuKα as a radiation source 20 copies. 0.2 part of a compound having a structure represented by the following formula (2).

10 parts of polyvinyl butyral resin (trade name: BX-1, manufactured by Sekisui Chemical Co., Ltd.). At this time, the dispersed particle diameter of the charge generation material CAPA-700 (manufactured by Horiba, Ltd.) was 0.15 μm. On the intermediate layer, this charge generation layer coating solution was applied by dip coating and dried at 100 ° C. for 10 minutes to form a charge generation layer having a thickness of 0.2 μm.

  Next, 7 parts of the compound formula (C) of the following structural formula, 1 part of the compound formula (D),

Then, 10 parts of the following polyarylate resin was dissolved in 50 parts of monochlorobenzene and 10 parts of dichloromethane to prepare a charge transport layer coating material. A bisphenol C-type polyarylate resin having a structural unit represented by the following formula (E) (a copolymer having a molecular weight of Mw 110000 and 50% of repeating structural units each having m-position and p-position between ester groups).

  This paint was applied onto the charge generation layer by a dip coating method and dried at 110 ° C. for 1 hour to form a charge transport layer having a thickness of 18 μm. Thus, an electrophotographic photosensitive member was prepared.

  The prepared electrophotographic photosensitive member is mounted on the following printer in an environment of normal temperature and normal humidity (23 ° C., 50% RH) and low temperature and low humidity (12 ° C., 10% RH). The image was evaluated for light potential fluctuation and image. Canon's laser beam printer LBP-2510 (process speed is 180mm / sec, pre-exposure can be turned on / off, charging conditions are variable, and laser exposure is variable). Details are as follows.

  The produced electrophotographic photosensitive member was attached to a cyan process cartridge of LBP-2510, and was attached to a cyan process cartridge station, and an image was output. The drum surface potential was set such that the initial dark portion potential was −500 V and the light portion potential was −120 V, and the light portion potential after 15,000 sheets were passed through was measured. Surface potential is measured by remodeling the cartridge, attaching a potential probe (model6000B-8: manufactured by Trek Japan) to the development position, and measuring the potential at the center of the drum with a surface potential meter (model344: Trek Japan, Inc.) )).

  When the paper was passed, a full color printing operation was performed on a character image with a printing rate of 1% for each color using plain paper of A4 size, and 15000 images were output without turning on the pre-exposure.

  The charging streaks were evaluated with halftone images of 1-dot Keima pattern.

  The criteria for image evaluation are as follows.

(Charging stripe)
Presence / absence of charged streaks, from a halftone image of 1-dot Keima pattern, A: no charged streaks, B: almost no charged streaks, C: slightly charged streaks, D: charged streaks observed E: The charging streaks are clearly understood.

  The evaluation of the repelling and unevenness of the photosensitive layer was performed visually after the charge generation layer was formed.

  The results are shown in Table 2.

( Reference Example 2 , Example 3, Reference Examples 4 to 6)
An electrophotographic photoreceptor was prepared and evaluated in the same manner as in Example 1 except that the imide compounds listed in Table 2 were used as the imide compounds.

(Example 7)
An electrophotographic photoreceptor was prepared and evaluated in the same manner as in Example 1 except that the polyamide resin added to the intermediate layer was changed to 9.5 parts and the imide compound was changed to 0.5 parts.

(Example 8)
An electrophotographic photosensitive member was prepared and evaluated in the same manner as in Example 1 except that 9 parts of the polyamide resin added to the intermediate layer and 1 part of the imide compound were changed.

Example 9
An electrophotographic photoreceptor was prepared and evaluated in the same manner as in Example 1 except that 5 parts of the polyamide resin added to the intermediate layer and 5 parts of the imide compound were changed.

(Example 10)
An electrophotographic photosensitive member was prepared and evaluated in the same manner as in Example 1 except that the polyamide resin added to the intermediate layer was changed to 3 parts and the imide compound was changed to 7 parts.

( Reference Example 11)
An electrophotographic photosensitive member was prepared and evaluated in the same manner as in Reference Example 5 except that the resin used for the intermediate layer was changed to polymethyl methacrylate (molecular weight Mw 120,000).

(Comparative Example 1)
An electrophotographic photoreceptor was prepared and evaluated in the same manner as in Example 1 except that the imide compound was changed to the compound of the following formula (F).

(Comparative Example 2)
An electrophotographic photoreceptor was prepared and evaluated in the same manner as in Example 1 without using an imide compound.

  The results are shown in Table 2.

(Example 12)
An electrophotographic photosensitive member was produced in the same manner as in Example 1 except that 5 parts of the polyamide resin added to the intermediate layer and 5 parts of the imide compound were changed.

  Evaluation was performed in the same manner as in Example 1 except that the pre-exposure was turned on.

(Example 13)
An electrophotographic photosensitive member was prepared and evaluated in the same manner as in Example 12 except that the intermediate layer was prepared as follows.

5 parts of a repeating unit unit of the formula (A) and a copolymer of styrene (30 mol% of the repeating unit unit of the formula (A), molecular weight Mw 42000) and 5 parts of the imide compound represented by the above formula (1) -1 . Dissolved in 100 parts of DMF and 100 parts of methanol. This solution was applied by a dip coating method and dried at 150 ° C. for 30 minutes to form an intermediate layer having a thickness of 0.7 μm.

The copolymer of the unit unit of formula (A) and styrene is 60.0 g of 2-isocyanatoethyl methacrylate, 72.8 g of styrene, 3 g of 2,2-azobis-isobutyronitrile (hereinafter AIBN) added to 100 g of toluene. And heated at 120 ° C. for 5 hours. The abundance ratio of the repeating unit unit of the formula (A) was determined from an infrared absorption spectrum. The peak of the isocyanate group in the vicinity of 2200 to 2300 cm ⁻¹ , the peak of NH— near 3350 cm ⁻¹ , 254 nm derived from the copolymerized styrene monomer. It was calculated from the ultraviolet absorption spectrum. The calculated abundance ratio was 30 mol%, which was almost equivalent to the charging ratio.

  In addition, the above-mentioned weight average molecular weight is a value obtained by converting a value obtained by measurement under the following conditions into polystyrene.

Measuring instrument: Gel permeation chromatography “HLC-8120”
(Manufactured by Tosoh Corporation)
Developing solvent: 0.1 mass% THF solution Column: “TSKgel SuperHM-N” manufactured by Tosoh Corporation
Detector: RI
Column temperature: 40 ° C
Injection volume: 20 μl
Flow rate: 1.0 ml / min

(Example 14)
An electrophotographic photosensitive member was prepared and evaluated in the same manner as in Example 13 except that the imide compound represented by the above formula (1) -3 was used as the imide compound .

(Example 15)
An electrophotographic photoreceptor was prepared and evaluated in the same manner as in Example 13 except that the amount of AIBN when synthesizing the copolymer resin was 8 g and the amount of toluene was 150 g. The molecular weight Mw of the resin was 1000.

(Example 16)
An electrophotographic photosensitive member was prepared and evaluated in the same manner as in Example 13 except that the amount of AIBN when synthesizing the copolymer resin was 1 g and the reaction time was 8 hours. The molecular weight Mw of the resin was 200000.

(Example 17)
An electrophotographic photoreceptor was prepared and evaluated in the same manner as in Example 13 except that the amount of AIBN when synthesizing the copolymer resin was 9 g, the amount of toluene was 150 g, and the reaction time was 4 hours. The molecular weight Mw of the resin was 800.

(Example 18)
An electrophotographic photoreceptor was prepared and evaluated in the same manner as in Example 13 except that the amount of AIBN when synthesizing the copolymer resin was 1 g, the amount of toluene was 80 g, and the reaction time was 8 hours. The molecular weight Mw of the resin was 250,000.

(Example 19)
An electrophotographic photoreceptor was prepared and evaluated in the same manner as in Example 12 except that the resin used for the intermediate layer was changed to butyral resin (Esrex BM-S, manufactured by Sekisui Chemical Co., Ltd.).

(Example 20)
An electrophotographic photosensitive member was prepared and evaluated in the same manner as in Example 12 except that the resin used for the intermediate layer was changed to polymethyl methacrylate (molecular weight Mw 120,000).

( Reference Example 21)
An electrophotographic photosensitive member was prepared and evaluated in the same manner as in Example 20 except that the imide compound represented by the above formula (1) -6 was used as the imide compound.

(Comparative Example 3)
An electrophotographic photoreceptor was prepared and evaluated in the same manner as in Example 12 except that the imide compound was changed to the following formula (F).

(Comparative Example 4)
An electrophotographic photoreceptor was prepared and evaluated in the same manner as in Example 12 except that the imide compound was changed to the following formula (G).

(Comparative Example 5)
An electrophotographic photoreceptor was prepared and evaluated in the same manner as in Example 12 except that the imide compound was changed to the following formula (H).

(Comparative Example 6)
An electrophotographic photoreceptor was prepared and evaluated in the same manner as in Example 12 except that the imide compound was changed to the following formula (I).

(Comparative Example 7)
An electrophotographic photoreceptor was prepared and evaluated in the same manner as in Example 12 except that no imide compound was used.

  The results are shown in Table 3.

FIG. 2 is a diagram showing an example of a schematic configuration of an electrophotographic apparatus having a process cartridge having the electrophotographic photosensitive member of the present invention. It is an infrared absorption spectrum of the imide compound shown by the said Formula (1) -1 of this invention. It is NMR of the imide compound shown by the said Formula (1) -1 of this invention.

Explanation of symbols

1: Electrophotographic photosensitive member 2: Rotating shaft 3: Primary charger (contact system, non-contact system, etc.)
4: Image exposure (laser light, etc.)
5: Developer (contact system, non-contact system, etc.)
6: Transfer charger (contact system, non-contact system, etc.)
7: Transfer material such as paper 8: Fixing device 9: Cleaner (may not be present)
10: Pre-exposure (may not be present)
11: Cartridge frame 12: Cartridge insertion guide

Claims (6)

An imide compound represented by the following formula (1) -1 or (1) -3 .
Conductive support and the intermediate layer on the conductive support, an electrophotographic photosensitive member comprising a photosensitive layer on the intermediate layer, the intermediate layer, comprise an imide compound according to claim 1 An electrophotographic photoreceptor characterized by the above. It said photosensitive layer comprises a charge generation layer, electric and a load generating layer a charge transport layer, charge transport layer is a hole transporting material electrophotographic photosensitive member according to including請 Motomeko 2. The intermediate layer, the electrophotographic photosensitive member according to polyamide resin including請 Motomeko 2 or 3. In an electrophotographic photosensitive member according to any one of claims 2 to 4, a charging means for charging the surface of the electrophotographic photosensitive member, an electrostatic latent image formed on the surface of the electrophotographic photoconductor toner developing means, and removes the toner remaining on the surface of the electrophotographic photosensitive member after transferring the toner image to the transfer material, recovered cleaning means for forming a toner image on the surface of the electrophotographic photosensitive member by developing A process cartridge which integrally supports at least one means selected from the group consisting of: and is detachable from the main body of the electrophotographic apparatus. The electrophotographic photosensitive member according to any one of claims 2 to 4, the electrophotographic photosensitive member charging means for charging the surface of the electrophotographic by row Ukoto the exposure to the charged electrophotographic photoconductor exposing means for forming an electrostatic latent image on the surface of the photoreceptor to form a toner image on the surface of the electrophotographic photosensitive member by developing the electrostatic latent image formed on the surface of the electrophotographic photosensitive member with toner developing means and an electrophotographic apparatus characterized in that it comprises a transfer means for transferring to a transfer material the toner image formed on the surface of the electrophotographic photosensitive member.