JP2006243487A - Electrophotographic photoreceptor, method for manufacturing the electrophotographic photoreceptor, and process cartridge and electrophotographic apparatus using the electrophotographic photoreceptor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electrophotographic photoreceptor that achieves a ghost image more server than ever without inducing changes in the sensitivity while keeping high sensitivity. <P>SOLUTION: The electrophotographic photoreceptor has an intermediate layer between a conductive supporting body and a photosensitive layer, wherein the intermediate layer contains a compound represented by formula (1). In formula (1), each of Z<SB>1</SB>and Z<SB>2</SB>independently represents oxygen, a C(CN)<SB>2</SB>group or N-R, wherein R is an aryl group or an alkyl group which may have a substituent; and each of X<SB>1</SB>to X<SB>8</SB>independently represents a hydrogen atom, a halogen atom, a nitro group, a trifluoroalkyl group, an alkoxy group which may have a substituent, or an alkyl group which may have a substituent. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an electrophotographic photoreceptor, which is a laminated electrophotographic photoreceptor having an intermediate layer, a charge generation layer, and a charge transport layer in this order on a conductive support, and the charge transport layer transports holes. The present invention relates to an electrophotographic photoreceptor comprising an agent, wherein the intermediate layer contains compounds represented by formulas (1) to (3). The present invention further relates to a method for producing the electrophotographic photosensitive member, a process cartridge using the electrophotographic photosensitive member, and an electrophotographic apparatus.

  Conventionally, as an electrophotographic photoreceptor, inorganic photoreceptors mainly composed of an inorganic photoconductive compound such as selenium, zinc oxide, cadmium sulfide have been widely used. In recent years, as seen in Patent Document 1, Patent Document 2, Patent Document 3, Patent Document 4, Patent Document 5, etc., a charge transport layer and a charge generation layer in which an organic photoconductive substance is bound with a resin or the like are used. Various proposals have been made regarding a laminated organic electrophotographic photosensitive member having a layer in which two functions are separated. In particular, an electrophotographic photosensitive member having a layer structure in which a charge transport layer is provided on a charge generation layer is excellent in durability and is currently mainstream. For example, Patent Document 6 discloses a photoreceptor having a charge transfer layer containing triallylpyrazoline, and Patent Document 7 discloses a charge generation layer formed of a derivative of perylene pigment and a charge transfer layer formed of a condensate of 3-propylene and formaldehyde. And the like. Patent Documents 8, 9 and the like disclose photoreceptors using disazo pigments or trisazo pigments as charge generation materials. Further, the organic photoconductive compound can freely select the photosensitive wavelength region of the electrophotographic photosensitive member depending on the compound. For example, with regard to azo organic pigments, Patent Documents 10 and 11 disclose high sensitivity in the visible region, and substances disclosed in Patent Document 12 and Patent Document 13 include red. Some have sensitivity even in the outer region.

  Among these materials, materials having sensitivity in the red or infrared region are used in laser beam printers, LED printers, and the like that have made remarkable progress in recent years, and the demand for these materials is increasing. Conventionally, copper phthalocyanine (Patent Document 14), metal-free phthalocyanine, and the like have been cited as materials having sensitivity in the infrared region, but this is insufficient for increasing sensitivity today. Further, in Patent Document 15 and the like, it has been proposed to increase sensitivity by adding an organic acceptor to the charge generation layer in the laminated organic electrophotographic photoreceptor, but this is not sufficient. Oxytitanium phthalocyanine pigments (Patent Literature 16, Patent Literature 17), gallium phthalocyanine pigments (Patent Literature 18, Patent Literature 19), chlorogallium phthalocyanine pigments (Patent Literature 20, Patent Literature 21), etc. Is attracting attention.

  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, the process speed is 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. In particular, a phenomenon in which the light-irradiated portion of one image is darkened only in the light-irradiated portion in the halftone image at the next rotation, a so-called positive ghost image, on the contrary, the density of the portion is lightened. The allowable range for so-called negative ghost images and the like has become much stricter than the allowable range of monochrome printers and monochrome copying machines. These ghost images are made of a highly sensitive charge generation material, so that the absolute number of carriers is large and electrons after holes are injected into the charge transport layer are likely to remain in the charge generation layer, resulting in a memory. In particular, this phenomenon becomes prominent when a highly sensitive material such as gallium phthalocyanine is used as the charge generation material.

  On the other hand, cost reduction and miniaturization are evolving year by year, and there is an increasing demand for less technology such as cleaner-less and pre-exposure-less. In particular, with regard to pre-exposure, black and white laser printers and black-and-white copiers are often not already installed, and it is easy to increase the number of color printers and color copiers that do not have pre-exposure. It can be imagined. However, the level of a ghost image in a color machine without pre-exposure needs to be several levels higher than that allowed by a black and white printer or black and white copier.

  Examples of proposals for reducing ghosts include an example in which polycyclic quinone and perylene are contained in the intermediate layer (Patent Document 22), an example using a metallocene compound and an electron-withdrawing compound, a melamine resin (Patent Document 23), and metal oxide fine particles And an example using a silane coupling agent (Patent Document 24), an example using metal oxide fine particles surface-treated with a silane coupling agent (Patent Document 25), etc. It was not effective for severe ghost levels.

  In addition, the ghost phenomenon and sensitivity change are particularly likely to occur in a photoconductor using an intermediate layer, compared to the case where a photosensitive layer is directly formed on a conductive substrate. That is, it is considered that the intermediate layer used for preventing the deterioration of the characteristics of the photosensitive member due to the defect of the substrate, the white spot and the black spot, causes a new ghost image defect and sensitivity change.

As described above, there is a demand for a photoreceptor that satisfies a severe ghost level in printers and copiers without pre-exposure, particularly color machines.
JP-A-57-54942 JP 60-59355 A JP-A-61-203461 JP-A 62-47054 JP-A 62-67094 U.S. Pat. No. 3,378,851 U.S. Pat. No. 3,871,882 Japanese Unexamined Patent Publication No. 9-33445 JP 56-46237 A JP 60-272754 A JP 56-167759 A JP-A-57-195767 Japanese Patent Laid-Open No. 61-228453 Japanese Patent Laid-Open No. 50-38543 JP-A-61-2157 JP-A-63-366 JP-A-1-319934 JP-A-5-249716 Japanese Patent Laid-Open No. 5-263007 JP-A-5-188615 JP-A-5-194523 Japanese Patent Application Laid-Open No. 8-14639 Japanese Patent Laid-Open No. 10-73942 JP-A-8-22136 JP 9-258469 A

  The object of the present invention was made in view of the above circumstances, and provides an electrophotographic photosensitive member that achieves a ghost image of a severe level that has never been achieved without causing a change in sensitivity while maintaining high sensitivity. It is.

  In the laminated electrophotographic photoreceptor having an intermediate layer, a charge generation layer, and a charge transport layer in this order on a conductive support of the electrophotographic photoreceptor, the intermediate layer has the following formulas (1) to ( It has been found that the above problem can be solved by including the compound represented by 3).

  Accordingly, the present invention is an electrophotographic photosensitive member having an intermediate layer between a conductive support and a photosensitive layer, wherein the intermediate layer contains a compound represented by the following formulas (1) to (3). And

  The present invention relates to the above electrophotographic photosensitive member, a charging means for charging the electrophotographic photosensitive member, a developing means for developing the electrophotographic photosensitive member on which the electrostatic latent image is formed with toner, and the electrophotographic photosensitive member after the transfer process. A process cartridge that integrally supports at least one means selected from the group consisting of cleaning means for collecting toner remaining on the body and is detachable from the main body of the electrophotographic apparatus.

  The present invention also provides an electrophotographic photosensitive member, a charging means for charging the electrophotographic photosensitive member, an exposure means for exposing the charged electrophotographic photosensitive member to form an electrostatic latent image, and the electrostatic latent image. An electrophotographic apparatus comprising: a developing unit that develops an electrophotographic photosensitive member having an image formed thereon with toner; and a transferring unit that transfers a toner image on the electrophotographic photosensitive member onto a transfer material.

  According to the present invention, in a laminated electrophotographic photosensitive member having an intermediate layer, a charge generation layer, and a charge transport layer in this order on a conductive support, the intermediate layer is represented by formulas (1) to (3). To provide an electrophotographic photosensitive member, a process cartridge, and an electrophotographic apparatus that include a compound and that achieve high ghost images of unprecedented levels without causing image density due to sensitivity changes while maintaining high sensitivity. Became possible.

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

  As the conductive support used in the present invention, a single metal or alloy such as aluminum, nickel, copper, gold, and iron, an insulating support such as polyester, polycarbonate, polyimide, and glass, aluminum, silver, gold, etc. Examples thereof include a single metal or a conductive thin film of an oxide such as indium oxide or tin oxide, carbon or conductive filler dispersed in a resin to impart conductivity. These support surfaces were subjected to electrochemical treatment such as anodization to improve electrical characteristics or adhesion, and conductive support surfaces were treated with alkali phosphate, phosphoric acid or tannic acid. It is also possible to use a solution obtained by dissolving a metal salt compound or a fluorine compound metal salt in an acidic aqueous solution containing as a main component and a chemical treatment.

  Further, when the present photoreceptor 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. Specifically, a support having the 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 an aluminum simple substance and an aluminum alloy. Must be used.

  As the honing treatment, there are dry and wet treatment methods, and any of them may be used. The wet honing treatment is a method of suspending a powdery abrasive in a liquid such as water and spraying the surface of the substrate at a high speed to roughen the surface. The surface roughness is the spray pressure, speed, 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 a conductive substrate 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 for the wet or dry honing treatment include particles of silicon carbide, alumina, iron, glass beads and the like.

In a method in which a conductive film composed of a conductive metal oxide and a binder resin is applied to a support of aluminum alone or an aluminum alloy to form a conductive support, a conductive fine particle is used as a filler in the conductive film. The powder which becomes is contained. In this method, the fine particles are dispersed in the film, so that the laser beam is diffusely reflected to prevent interference fringes and to 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, an appropriate specific resistance is imparted to the fine particles by providing a conductive coating layer with tin oxide or the like. The specific resistance of the conductive fine particle powder is preferably 0.1 to 1000 Ωcm, more preferably 1 to 1000 Ωcm. In the present invention, the powder specific resistance was measured by using a resistance measuring device Loresta AP (Loresta Ap) manufactured by Mitsubishi Chemical Corporation. The powder to be measured was caulked at a pressure of 500 kg / cm ² and attached to the measuring device as a coin-like sample. The average particle size of the fine particles is preferably 0.05 to 1.0 μm, more preferably 0.07 to 0.7 μm. In the present invention, the average particle diameter of the fine particles is a value measured by a centrifugal sedimentation method. The filler content is preferably 1.0 to 90 mass%, more preferably 5.0 to 80 mass% with respect to the conductive coating layer. The coating layer may contain fluorine or antimony as necessary.

  As the binder resin used for the conductive film of the present invention, 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 dispersibility of the filler used in the present invention, 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 to 30 μm, more preferably 0.5 to 20 μm. The volume resistivity of the conductive film is preferably 10 ¹³ Ωcm or less, more preferably 10 ¹² Ωcm or less and 10 ⁵ Ωcm or more. In the present invention, the volume resistivity is obtained by forming a conductive film to be measured on an aluminum plate, further forming a gold thin film on this film, and calculating the current value flowing between both the aluminum plate and the gold thin film as pA. It was determined by measuring with a meter. In addition to the powder composed of barium sulfate fine particles having a coating layer, the conductive film may contain a filler composed of powder such as zinc oxide and titanium oxide. 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 is formed by applying an intermediate layer coating solution in which at least compounds represented by the following formulas (1) to (3) are dissolved on a conductive support and drying.

Wherein Z ₁ and Z ₂ each independently represent oxygen, C (CN) ₂ group or N—R (R represents an aryl group or alkyl group which may have a substituent), and X ₁ to X ₈ Each independently represents a hydrogen atom, a halogen atom, a nitro group, a trifluoroalkyl group, an optionally substituted alkoxy group or an optionally substituted alkyl group.)

Wherein Z ₃ and Z ₄ each independently represent oxygen, C (CN) ₂ group or N—R (R represents an aryl group or alkyl group which may have a substituent), and X ₁₀ to X ₁₅ Each independently represents a hydrogen atom, a halogen atom, a nitro group, a trifluoroalkyl group, an optionally substituted alkoxy group or an optionally substituted alkyl group.)

(Wherein Z ₅ and Z ₆ each independently represent oxygen, C (CN) ₂ group or N—R (R represents an aryl group or alkyl group which may have a substituent), and X ₂₀ to X ₂₅ Each independently represents a hydrogen atom, a halogen atom, a nitro group, a trifluoroalkyl group, an optionally substituted alkoxy group or an optionally substituted alkyl group.)
In the present invention, the reason why the ghost image is suppressed by adding the compounds (1) to (3) to the intermediate layer is not clear, but is considered as follows. In the ghost image, a potential difference after the next rotation exposure is generated due to the difference in the number of carriers remaining in the exposed portion and the unexposed portion.

  Charge is generated in the charge generating agent by exposure, and the separated hole and electron carriers move through the binder resin. In the case of a negatively charged laminated photoconductor, holes are injected into the charge transport layer containing the hole transport material, but electrons are likely to remain as a kind of charge at the interface between the charge generation layer and the intermediate layer, and the potential difference during the next rotation exposure. It is thought to give rise to. This potential difference causes a change in image density due to a ghost image or a sensitivity change, but the compound of the present invention seems to have some effect on the remaining charge. Therefore, the effect obtained varies depending on the combination of the charge generating agent and the intermediate layer, and the compound of the present invention showed good characteristics in combination with the phthalocyanine charge generating agent, particularly gallium phthalocyanine.

  In addition, the intermediate layer may contain a binder resin having an adhesive function and a barrier function, if necessary. Examples of the binder resin include polyamide, polyvinyl alcohol, polyethylene oxide, ethyl cellulose, casein, polyurethane, and polyether urethane. And thermosetting materials such as thermoplastic resins, melamine resins, phenol resins, alkyd resins, epoxy resins, silane coupling agents, and organometallic complexes. The addition ratio of the compounds (1) to (3) is preferably 5 to 95 wt%, more preferably 25 to 80 wt% with respect to the entire intermediate layer.

  In addition, the compound having any structure is effective, but a compound having a reduction potential of 0 to −0.8 V (vs. SCE) is preferable, and a compound of −0.25 to −0.65 V (vs. SCE) is more preferable. More preferred. The reduction potential described here is a potential at the peak current value.

  The above-mentioned material is dissolved and applied in a suitable solvent, and the thickness of the intermediate layer is preferably 0.05 to 5 μm, particularly 0.3 to 3 μm.

  Solvents used are alcohols, sulfoxides, ketones, ethers, esters, aliphatic halogenated hydrocarbons, aromatic compounds and the like.

  Next, although the compound example of the said General formula (1)-(3) is shown in Tables 1-4, it is not necessarily limited to these.

  As the charge generation material used in the charge generation layer of the present invention, pyrylium dyes, thiopyrylium dyes, phthalocyanine pigments, anthanthrone pigments, dibenzpyrenequinone pigments, pyratron pigments, azo pigments, indigo pigments, quinacridone And pigments and quinocyanine dyes. Examples of the phthalocyanine compound (phthalocyanine pigment) include metal-free phthalocyanine, oxytitanium phthalocyanine, hydroxyphthalocyanine, and gallium halide phthalocyanine such as chlorogallium. Although details are not clear, in the present invention, when gallium phthalocyanine, particularly hydroxygallium phthalocyanine is used, a particularly preferable ghost suppressing effect is obtained.

  The charge generation layer may contain a charge generation material other than the phthalocyanine compound (phthalocyanine pigment) up to 50 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 is a homogenizer, ultrasonic dispersion, ball mill, vibration ball mill, sand mill, attritor, roll mill or liquid collision type high-speed disperser together with the charge generation material in a mass ratio of 0.3 to 4 times the binder resin and solvent. And the like, and then a coating obtained by adding an electron transporting compound to the dispersion is applied and dried. As binder resin, butyral resin, polyester resin, polycarbonate resin, polyarylate resin, polystyrene resin, polyvinyl methacrylate resin, polyvinyl acrylate resin, polyvinyl acetate resin, polyvinyl chloride resin, polyamide resin, polyurethane resin, silicone resin, alkyd resin , Epoxy resin, cellulose resin, melamine resin and the like, but are not limited thereto. In particular, a butyral resin is preferred. The thickness of the charge generation layer is preferably 5 μm or less, particularly preferably 0.1 to 2 μm.

  Examples of the solvent used include alcohols, sulfoxides, ketones, ethers, esters, aliphatic halogenated hydrocarbons, aromatic compounds, and the like. Specific examples include cyclohexanone, ethyl acetate, and tetrahydrofuran.

  In addition, various sensitizers, antioxidants, ultraviolet absorbers, plasticizers, and the like can be added to the charge generation layer as necessary.

  A charge transport layer is formed on the charge generation layer. The charge transport layer is formed by applying and drying a paint obtained by dissolving a charge transport material and a binder resin in a solvent. The charge transport material used in the present invention is a hole transport agent, and examples thereof 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, silicone resin, alkyd resin, epoxy resin, cellulose resin, and melamine resin. When using a polyarylate resin having a structural unit represented by the following formula (4), a particularly preferable ghost suppressing effect was obtained.

  The polyarylate resin having a structural unit represented by the following formula (4) may be used alone or as a resin such as polycarbonate resin, polyester resin, polymethacrylic acid ester, polystyrene resin, acrylic resin, polyamide resin, poly-N-vinylcarbazole, polyvinyl It is preferable to use a mixture with an organic photoconductive polymer such as anthracene.

(Wherein, X ¹ represents a carbon atom or a single bond (in which R ⁵ and R ^{6 are} absent), and R ^{1 to} R ⁴ represent a hydrogen atom, a halogen atom, an optionally substituted alkyl group or an aryl group. , R ⁵ and R ⁶ represent a hydrogen atom, a halogen atom, an optionally substituted alkyl group, an aryl group, or an alkylidene group formed by combining R ⁵ and R ⁶ , and R ^{7 to} R ¹⁰ represent a hydrogen atom Represents 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, and 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, 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 (“TSKgel SuperHM-N” manufactured by Tosoh Corporation), RI was used as a detector, under 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 in an amount of 0.5 to 2 times by mass, dissolved in a solvent, applied and dried to form a charge transport layer. The film thickness of the charge transport layer is preferably 5 to 30 μm, and more preferably 8 to 19 μm.

  Solvents used include ketones such as acetone and methyl ethyl ketone, esters such as methyl acetate and ethyl acetate, aromatic hydrocarbons such as toluene and xylene, ethers such as 1,4-dioxane and tetrahydrofuran, chlorobenzene, chloroform and carbon tetrachloride. A hydrocarbon substituted with a halogen atom is used. 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.

  The photosensitive layer of the present invention is composed of the charge generation layer and the charge transport layer.

  Furthermore, in the present invention, a protective layer may be provided on the charge transport layer.

  The material constituting the protective layer is polyester, polyacrylate, polyethylene, polystyrene, polybutadiene, polycarbonate, polyamide, polypropylene, polyimide, polyamideimide, polysulfone, polyacryl ether, polyacetal, phenol, acrylic, silicone, epoxy, urea, allyl. Alkyd, butyral, phenoxy, phosphazene, acrylic-modified epoxy, acrylic-modified urethane, and acrylic-modified polyester resin. The thickness of the protective layer is preferably 0.2 to 10 μm.

  The protective layer is formed using, for example, a coating method such as a dip coating method (dip coating method), a spray coating method, a spinner coating method, a roller coating method, a Meyer bar coating method, or a blade coating method.

  Each of the above layers has a polytetrafluoroethylene, polyvinylidene fluoride, a fluorine-based graft polymer, a silicone-based graft polymer, a fluorine-based block polymer, a silicone-based block polymer, and a silicone for improving cleaning properties and abrasion resistance. You may contain lubricants, such as system oil.

  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.

The electrostatic capacity per 1 cm ^{2 of the} photoreceptor is preferably 135 pF / cm ² or more. Furthermore, 150 pF / cm ² or more and 400 pF / cm ² or less are preferable. The electrostatic capacity of the photoreceptor is determined by all the layers of the photosensitive layer, and is also slightly affected by the relationship between the layers. In the layer structure, the charge transport layer has the largest ratio of controlling the capacitance among the film structures of the photoconductor. Among them, the relative permittivity ε of the binder resin and the film thickness of the charge transport layer have a great influence. give. The relative dielectric constant of the binder resin of the charge transport layer is preferably 2.6 to 3.5, and more preferably 2.8 to 3.2. The capacitance is measured by producing an electrode of a certain area on the surface of the photoreceptor by gold sputtering or the like, and using an impedance measuring instrument (4192A manufactured by YHP Co., Ltd.), the capacitance when the frequency is 1 kHz. The area of the electrode was divided from the measured value to obtain a measured value of capacitance per 1 cm ² . With respect to a sample having a curvature, for example, it is cut into about 2 cm square, and a 1 cm ² electrode can be produced by gold sputtering and measured. In some cases, the instrument may need some modifications.

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

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

  The formed electrostatic latent image is then developed with toner by the developing unit 5, and the developed toner developed image is rotated between the photosensitive member 1 and the transfer unit 6 from a sheet feeding unit (not shown). The image is sequentially transferred by the transfer means 6 to the transfer material 7 that is synchronously taken out and fed.

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

  The surface of the photoreceptor 1 after the image transfer is cleaned by the transfer unit 9 after the transfer residual toner is removed, and is repeatedly used for image formation.

  The primary 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. As a material for the member of the contact charger, an elastic body imparted with conductivity is usually used. The voltage applied to the contact charging member may be only a DC voltage or an oscillating voltage obtained by superimposing an AC voltage on the DC voltage. The oscillating voltage referred to here is a voltage whose voltage value periodically changes with time, and the AC voltage has a peak-to-peak voltage that is at least twice the charging start voltage of the photosensitive member when only the DC voltage is applied. preferable.

  In the present invention, a plurality of components such as the electrophotographic photosensitive member 1, the primary charging unit 3, the developing unit 5 and the cleaning unit 9 described above are integrally coupled as a process cartridge. May be configured to be detachable from an electrophotographic apparatus main body such as a copying machine or a laser beam printer. For example, at least one of the primary charging unit 3, the developing unit 5, and the cleaning unit 9 is integrally supported together with the 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. The process cartridge 11 can be obtained.

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

  First, the manufacture example of the hydroxygallium phthalocyanine used for this invention is shown.

<Production Example 1>
After reacting 73 g of o-phthalodinitrile, 25 g of gallium trichloride and 400 ml of α-chloronaphthalene at 200 ° C. for 4 hours in a nitrogen atmosphere, the product was filtered at 130 ° C. The obtained product was dispersed and washed at 130 ° C. for 1 hour using N, N-dimethylformamide, filtered, washed with methanol and dried to obtain 45 g of chlorogallium phthalocyanine.

  15 g of the chlorogallium phthalocyanine obtained here was dissolved in 450 g of concentrated sulfuric acid at 10 ° C., dropped into 2300 g of ice water with stirring, reprecipitated and filtered. After being dispersed and washed with 2% aqueous ammonia and sufficiently washed with ion-exchanged water, it was filtered and dried to obtain 13 g of hydroxygallium phthalocyanine. In the pigmentation step, 10 g of the obtained hydroxygallium phthalocyanine and 300 g of N, N′-dimethylformamide were milled together with 450 g of 1 mmφ glass beads at room temperature (22 ° C.) for 6 hours.

  The solid was taken out from this dispersion, washed thoroughly with methanol and then with water, and dried to obtain 9.2 g of hydroxygallium phthalocyanine crystals. This hydroxygallium phthalocyanine had strong peaks at 7.4 ° and 28.2 ° of the Bragg angle (2θ ± 0.2 °) in CuKα characteristic X-ray diffraction.

  EXAMPLES Next, although an Example demonstrates this invention concretely, this invention is not limited by these Examples.

  A 3003 outer diameter φ30.5 mm, inner diameter φ28.5 mm, length 260.5 mm aluminum base pipe (ED pipe) obtained by hot extrusion was prepared.

  120 parts by mass (hereinafter abbreviated as “parts”) of a powder composed of fine particles of barium sulfate having a coating layer formed of tin oxide (coverage: 50 mass%, powder specific resistance: 700 Ωcm) and resol type phenol resin (trade name: A solution composed of 70 parts of BRIO-Fen J-325, manufactured by Dainippon Ink & Chemicals, Inc., solid content 70%) and 100 parts of 2-methoxy-1-propanol was dispersed with a ball mill for about 20 hours to obtain conductive particles. A coating solution for the resin dispersion layer was prepared (the average particle size of the filler contained in the coating solution was 0.22 μm). This liquid is applied on an aluminum cylinder having an outer diameter of 29.92 mmφ, an inner diameter of 28.5 mmφ, and a length of 260 mm by a dip coating method, and is heated and cured at 140 ° C. for 30 minutes, thereby forming a conductive particle resin having a thickness of 10 μm. A dispersion layer was formed and used as a conductive support.

  2 parts of [E2-2] (reduction potential -0.37 V) listed in Table 2, 4 parts of N-methoxymethylated nylon and 4 parts of copolymer nylon on the above conductive support, 150 parts of DMF and 100 parts of methanol, The solution dissolved in 1 was applied by a dip coating method and dried at 90 ° C. for 5 minutes to form an intermediate layer having a thickness of 0.4 μm.

  Next, 350 parts of cyclohexanone is added to 20 parts of a hydroxygallium phthalocyanine crystal synthesized according to Production Example 1 as a charge generation material and 10 parts of polyvinyl butyral resin (trade name: BX-1, manufactured by Sekisui Chemical Co., Ltd.). The mixture was dispersed for 3 hours with a sand mill using 1, and diluted with 1200 parts of ethyl acetate. At this time, the dispersed particle diameter of CAPA-700 (manufactured by Horiba, Ltd.) of the charge generation material was 0.15 μm. This charge generation layer coating solution was dip-coated on the intermediate layer and dried at 100 ° C. for 10 minutes to form a charge generation layer having a thickness of 0.15 μm.

  Next, 7 parts of the compound of the following formula (5), 1 part of the compound of the formula (6),

And 10 parts of C type polyarylate resin shown by Formula (7) was melt | dissolved in 50 parts of monochlorobenzene and 10 parts of dichloromethane, and the coating material for charge transport layers was prepared. 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 produced.

  As an evaluation method, the produced electrophotographic photosensitive member is a color laser printer manufactured by Hewlett-Packard Co., Ltd., laser jet 4600 remodeling machine (primary charging: roller contact DC charging, dark part potential -500 V, process speed 100 mm / second, laser The ghost image was evaluated immediately after the endurance of 3000 sheets in a 4% image density image in an environment of 15 ° C./10% RH with the pre-exposure removed. The ghost image is produced in a single color of magenta, cyan, yellow, and black. For example, in the case of black, as shown in FIG. A halftone image was prepared. The order of image production is to take a solid white image as the first image, then take five consecutive ghost images, then take one solid black image and then take five ghost images again for a total of ten images. Evaluation was performed using a ghost image.

  The evaluation of the ghost image is carried out by measuring the density difference between the Keima pattern image density and the image density of the ghost part with a spectral densitometer X-Rite 504/508 (manufactured by X-Rite Co., Ltd.) at 10 points with one ghost image. Then, the average of those 10 points was taken as one result, and all the above-mentioned 10 ghost images were measured in the same manner. Their average value was determined. By this method, the other three colors were similarly processed, and evaluation was performed using an average value of these values. As the measurement result of each color, the result of each color of magenta, cyan, yellow, and black of the spectral densitometer X-Rite is displayed, and the value of the same color as the image color is used as the measurement value. The evaluation of the density difference was performed by outputting a halftone image with a 1-dot Keima pattern continuously for 100 sheets, and measuring the difference between the image density of the first sheet and the image density of the 100th sheet in the same manner as the ghost portion evaluation. The results are shown in Table 5.

  An electrophotographic photoreceptor was prepared and evaluated in the same manner as in Example 1 except that the compound [E2-2] added to the intermediate layer was changed to 8 parts. The results are shown in Table 5.

  An electrophotographic photosensitive member was prepared and evaluated in the same manner as in Example 1 except that the compound added to the intermediate layer was changed to [E1-8] (reduction potential -0.24 V). The results are shown in Table 5.

  An electrophotographic photosensitive member was prepared and evaluated in the same manner as in Example 1 except that the compound added to the intermediate layer was changed to [E3-4] (reduction potential -0.46 V). The results are shown in Table 5.

  An electrophotographic photoreceptor was prepared and evaluated in the same manner as in Example 1 except that the compound added to the intermediate layer was changed to [E1-1] (reduction potential -0.71 V). The results are shown in Table 5.

  An electrophotographic photosensitive member was prepared in the same manner as in Example 1 except that 7 parts of [E2-2] as an intermediate layer coating solution, 1.5 parts of N-methoxymethylated nylon and 1.5 parts of copolymer nylon were used. Similar evaluations were made. The results are shown in Table 5.

  An electrophotographic photosensitive member was prepared in the same manner as in Example 2 except that the C-type polyarylate resin of the solution for the charge transport layer was changed to bisphenol Z-type polycarbonate resin (trade name: Iupilon, manufactured by Mitsubishi Engineering Plastics Co., Ltd.). Similar evaluations were made. The results are shown in Table 5.

  Crystalline oxy having strong peaks at 9.0 °, 14.2 °, 23.9 ° and 27.1 ° of Bragg angles (2θ ± 0.2 °) in characteristic X-ray diffraction of CuKα as a charge generating material An electrophotographic photosensitive member was produced in the same manner as in Example 2 except that titanium phthalocyanine was used, and the same evaluation was performed. The results are shown in Table 5.

Chlorogallium phthalocyanine having strong peaks at 7.4 °, 16.6 °, 25.5 ° and 28.2 ° of the Bragg angle (2θ ± 0.2 °) in the characteristic X-ray diffraction of CuKα as a charge generation material. An electrophotographic photosensitive member was produced in the same manner as in Example 2 except that it was used, and the same evaluation was performed. The results are shown in Table 5.
[Comparative Example 1]
An electrophotographic photoreceptor was prepared and evaluated in the same manner as in Example 2 except that [E2-2] shown in Table 2 was not used as the intermediate layer coating solution. The results are shown in Table 5.
[Comparative Example 2]
An electrophotographic photoreceptor was prepared and evaluated in the same manner as in Example 2 except that the compound added to the intermediate layer was changed to the following structural formula E-4 (no reduction peak in the range of 0 to -0.8 V). It was. The results are shown in Table 5.

[Comparative Example 3]
An electrophotographic photosensitive member was produced and evaluated in the same manner as in Example 2 except that the compound added to the intermediate layer was changed to the following structural formula E-5 (reduction potential -0.64 V). The results are shown in Table 5.

[Comparative Example 4]
An electrophotographic photosensitive member was prepared and evaluated in the same manner as in Example 2 except that the compound added to the intermediate layer was changed to the following structural formula E-6 (reduction potential -0.54 V). The results are shown in Table 5.

  It can be expected to be used as a photoreceptor satisfying a severe ghost level in printers and copying machines without pre-exposure, particularly color machines.

1 is a diagram illustrating an example of a schematic configuration of an electrophotographic apparatus including a process cartridge having the electrophotographic photosensitive member of the present invention. It is a figure which shows an example of a ghost image.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Electrophotographic photosensitive member 2 Shaft 3 Charging means 4 Exposure light 5 Developing means 6 Transfer means 7 Transfer material 8 Fixing means 9 Cleaning means 11 Process cartridge 12 Rail

Claims (10)

In the electrophotographic photosensitive member having an intermediate layer between the conductive support and the photosensitive layer, the intermediate layer is represented by the following formula (1).

Wherein Z ₁ and Z ₂ each independently represent oxygen, C (CN) ₂ group or N—R (R represents an aryl group or alkyl group which may have a substituent), and X ₁ to X ₈ Each independently represents a hydrogen atom, a halogen atom, a nitro group, a trifluoroalkyl group, an optionally substituted alkoxy group or an optionally substituted alkyl group.)
An electrophotographic photoreceptor comprising a compound represented by the formula:   The photosensitive layer is composed of a charge generation layer and a charge transport layer, and the electrophotographic photosensitive member has the intermediate layer, the charge generation layer, and the charge transport layer in this order on the conductive support. 2. The electrophotographic photoreceptor according to claim 1, wherein the electrophotographic photoreceptor is an electrophotographic photoreceptor, and the charge transport layer contains a hole transport agent. In the electrophotographic photosensitive member having an intermediate layer between the conductive support and the photosensitive layer, the intermediate layer is represented by the following formula (2).

Wherein Z ₃ and Z ₄ each independently represent oxygen, C (CN) ₂ group or N—R (R represents an aryl group or alkyl group which may have a substituent), and X ₁₀ to X ₁₅ Each independently represents a hydrogen atom, a halogen atom, a nitro group, a trifluoroalkyl group, an optionally substituted alkoxy group or an optionally substituted alkyl group.)
An electrophotographic photoreceptor comprising a compound represented by the formula:   The photosensitive layer is composed of a charge generation layer and a charge transport layer, and the electrophotographic photosensitive member has the intermediate layer, the charge generation layer, and the charge transport layer in this order on the conductive support. 4. The electrophotographic photoreceptor according to claim 3, wherein the electrophotographic photoreceptor is an electrophotographic photoreceptor, and the charge transport layer contains a hole transport agent. In the electrophotographic photosensitive member having an intermediate layer between the conductive support and the photosensitive layer, the intermediate layer is represented by the following formula (3).

(Wherein Z ₅ and Z ₆ each independently represent oxygen, C (CN) ₂ group or N—R (R represents an aryl group or alkyl group which may have a substituent), and X ₂₀ to X ₂₅ Each independently represents a hydrogen atom, a halogen atom, a nitro group, a trifluoroalkyl group, an optionally substituted alkoxy group or an optionally substituted alkyl group.)
An electrophotographic photoreceptor comprising a compound represented by the formula:   The photosensitive layer is composed of a charge generation layer and a charge transport layer, and the electrophotographic photosensitive member has the intermediate layer, the charge generation layer, and the charge transport layer in this order on the conductive support. 6. The electrophotographic photoreceptor according to claim 5, wherein the electrophotographic photoreceptor is an electrophotographic photoreceptor, and the charge transport layer contains a hole transport agent.   The electrophotographic photosensitive member according to claim 2, wherein the charge generation material in the charge generation layer is gallium phthalocyanine.   The electrophotographic photosensitive member according to claim 7, wherein the gallium phthalocyanine is hydroxygallium phthalocyanine.   9. The electrophotographic photosensitive member according to claim 1, a charging unit for charging the electrophotographic photosensitive member, a developing unit for developing the electrophotographic photosensitive member having an electrostatic latent image formed thereon with toner, and a transfer step. A process cartridge characterized in that it integrally supports at least one means selected from the group consisting of cleaning means for collecting toner remaining on a later electrophotographic photosensitive member, and is detachable from the electrophotographic apparatus main body. .   The electrophotographic photosensitive member according to any one of claims 1 to 8, a charging unit for charging the electrophotographic photosensitive member, an exposure unit for exposing the charged electrophotographic photosensitive member to form an electrostatic latent image, An electrophotographic apparatus comprising: developing means for developing an electrophotographic photosensitive member on which an electrostatic latent image is formed with toner; and transfer means for transferring a toner image on the electrophotographic photosensitive member onto a transfer material.