JP2007052063A - Electrophotographic photoreceptor, and process cartridge and electrophotographic apparatus with the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electrophotographic photoreceptor capable of outputting a good image and having good potential characteristic, and a process cartridge and an electrophotographic apparatus with the electrophotographic photoreceptor. <P>SOLUTION: The electrophotographic photoreceptor contains a compound selected from specific bipyridyl compounds represented by structural formulae (1)-(16) (compounds having pyridyl rings on both sides of a quinoid ring). The process cartridge and the electrophotographic apparatus with the electrophotographic photoreceptor are also provided. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an electrophotographic photosensitive member containing a compound having a specific structure in the photosensitive member, a process cartridge and an electrophotographic apparatus using the same.

  Conventionally, as an electrophotographic photosensitive member, an inorganic photosensitive member mainly composed of an inorganic photoconductive compound such as selenium, zinc oxide, cadmium sulfide has been widely used. In recent years, various proposals have been made regarding laminated organic electrophotographic photoreceptors having two functionally separated layers, a charge transport layer in which an organic photoconductive compound is bound with a resin or the like, and a charge generation layer (for example, Patent Documents 1 to 5).

  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, a photoreceptor having a charge transfer layer containing triallyl pyrazoline (for example, Patent Document 6), a charge generation layer made of a derivative of perylene pigment, and a charge transfer layer made of a condensate of 3-propylene and formaldehyde. The body (for example, patent document 7) etc. are disclosed. In addition, there are photoreceptors using disazo pigments or trisazo pigments as charge generation materials (for example, Patent Documents 8 and 9). Further, the organic photoconductive compound can freely select the photosensitive wavelength range of the electrophotographic photosensitive member depending on the compound. For example, azo-based organic pigments that exhibit high sensitivity in the visible region (for example, Patent Documents 10 and 11) are disclosed, and those that have sensitivity in the infrared region (for example, Patent Document 12). 13).

  Among these materials, materials having sensitivity in the red or infrared region are used in laser beam printers and LED printers that have made remarkable progress in recent years, and the frequency of demand thereof is increasing. Conventionally, copper phthalocyanine (for example, Patent Document 14), metal-free phthalocyanine, and the like are listed as materials having sensitivity in the infrared region. Furthermore, in a multilayer organic electrophotographic photoreceptor, it has been proposed to increase the sensitivity by adding an organic acceptor to the charge generation layer (for example, Patent Document 15), but this is not sufficient. Oxytitanium phthalocyanine pigments (for example, Patent Documents 16 and 17), gallium phthalocyanine pigments (for example, Patent Documents 18 and 19), chlorogallium phthalocyanine pigments (for example, Patent Documents 20 and 21), etc. Photoconductors using these have achieved high quantum efficiency.

  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 use a highly sensitive charge generation material because 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 memory. This phenomenon is considered to be a particularly remarkable phenomenon in recent high-sensitivity charge generation materials.

  For example, it has been disclosed that a charge generation layer using oxytitanium phthalocyanine contains an acceptor compound to reduce residual potential and ghost (Patent Document 22). After standing for a period of time and making the phenomenon noticeable, ghost evaluation is performed, which shows the effect of ghosting by + charged memory, which is different from ordinary ghosts. In addition, the addition of an electron transporting material, an electron acceptor or an electron withdrawing substance to the charge generation layer (for example, Patent Documents 23 to 30) is disclosed, but is effective for the severe ghost level as described above. It wasn't. Further, although a method for producing a phthalocyanine pigment produced by adding an electron transporting material during the phthalocyanine pigmentation step is disclosed (for example, Patent Document 31), the electron transporting material is located near a charge generating substance in this publication. Although it is disclosed that achieving high sensitivity is important, this is also not effective for the severe ghost level as described above.

  Many electron-transporting materials are disclosed as positively charged photoreceptors or single-layer photoreceptor materials (for example, Patent Documents 32 and 33), but they are also effective for the above severe ghost levels. There wasn't.

In addition, since the electrophotographic apparatus has entered the market that has conventionally been a printing area such as offset printing and screen printing, an increase in printing speed is required. Along with this, the process speed is increasing year by year, and the potential stability is more demanded.
JP-A-57-54942 JP 60-59355 A JP-A-61-203461 JP-A 62-47054 JP-A 62-67094 USP3837851 gazette US Pat. No. 3,871,882 JP 60-29108 A 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 JP 7-104495 A Japanese Patent Laid-Open No. 2-136860 JP-A-2-136661 Japanese Patent Laid-Open No. 2-146048 Japanese Patent Laid-Open No. 2-146049 JP-A-2-146050 JP-A-5-150498 JP-A-6-313974 JP 2000-39730 A JP 2001-040237 A JP-A-8-15879 JP-A-9-12555

  An object of the present invention is to provide an electrophotographic photosensitive member capable of outputting a good image and good potential characteristics, and a process cartridge and an electrophotographic apparatus having the electrophotographic photosensitive member.

  As a result of intensive studies, the present inventors have found that the above object can be achieved by including a compound having a specific structure in the electrophotographic photosensitive member.

  That is, the present invention is an electrophotographic photoreceptor comprising any compound represented by the following structural formulas (1) to (6).

In formulas (1) to (6), X ₁ and X ₂ are O, C (CN) R, C (CN) COR, C (CN) COOR, C (COOR) ₂ , CHR or NR, (R is Substituted or unsubstituted aromatic group, substituted or unsubstituted aliphatic group or cyano group).

In formulas (1) to (6), R _{1 to} R ₆ are a substituted or unsubstituted aromatic group, a substituted or unsubstituted aliphatic group, an alkoxy group, an ester group, a nitro group, a cyano group, a halogen atom, or a hydrogen atom. Indicates.

  The present invention also provides an electrophotographic photosensitive member containing any one of the compounds represented by the following structural formulas (7) to (16).

In the formulas (7) to (16), X ₁ is O, C (CN) R, C (CN) COR, C (CN) COOR, C (COOR) ₂ , CHR or NR, (R is substituted or unsubstituted An aromatic group, a substituted or unsubstituted aliphatic group or a cyano group).

In formulas (7) to (16), R _{1 to} R ₆ are a substituted or unsubstituted aromatic group, a substituted or unsubstituted aliphatic group, an alkoxy group, an ester group, a nitro group, a cyano group, a halogen atom, or a hydrogen atom. Indicates.

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

  By including a compound having a specific structure in an electrophotographic photosensitive member, an electrophotographic photosensitive member capable of outputting a good image and having good potential characteristics, and a process cartridge and an electrophotographic apparatus having the electrophotographic photosensitive member are provided. Can be provided.

  Hereinafter, the present invention will be described in more detail.

  First, the configuration of the electrophotographic photosensitive member of the present invention will be described.

  The electrophotographic photoreceptor of the present invention forms a photosensitive layer on a conductive support. The photosensitive layer of the present invention comprises a single layer type containing both a charge generation material and a charge transport material in the same layer, and a charge generation layer containing a charge generation material and a charge transport layer containing a charge transport material. It is divided roughly into the laminated type which has. As a laminated type structure, a charge generation layer and a charge transport layer are laminated on a support in this order (forward layer type), and conversely, a charge transport layer and a charge generation layer are laminated in order (reverse layer type). There is.

  The compounds contained in the electrophotographic photoreceptor of the present invention (compounds having pyridyl rings on both sides of the quinoid ring: hereinafter abbreviated as bipyridyl compounds) (1) to (16) are contained in the photoreceptors of any of the above configurations. May be.

In formulas (1) to (6), X ₁ and X ₂ are O, C (CN) R, C (CN) COR, C (CN) COOR, C (COOR) ₂ , CHR or NR, (R is Substituted or unsubstituted aromatic group, substituted or unsubstituted aliphatic group or cyano group).

In formulas (1) to (6), R _{1 to} R ₆ are a substituted or unsubstituted aromatic group, a substituted or unsubstituted aliphatic group, an alkoxy group, an ester group, a nitro group, a cyano group, a halogen atom, or a hydrogen atom. Indicates.

In the formulas (7) to (16), X ₁ is O, C (CN) R, C (CN) COR, C (CN) COOR, C (COOR) ₂ , CHR or NR, (R is substituted or unsubstituted An aromatic group, a substituted or unsubstituted aliphatic group or a cyano group).

In formulas (7) to (16), R _{1 to} R ₆ are a substituted or unsubstituted aromatic group, a substituted or unsubstituted aliphatic group, an alkoxy group, an ester group, a nitro group, a cyano group, a halogen atom, or a hydrogen atom. Indicates.

  Examples of bipyridyl compounds are shown in Tables 1 and 2 below, but are not limited thereto.

  In the case of the laminated type, the charge used varies depending on the charge polarity, and therefore the materials used are different. The charge transport layer of the forward layer type used in the negative charge and the reverse layer type charge transport layer used in the positive charge contains a hole transporting material, and the forward layer type used in the positive charge and the reverse layer type charge transport layer used in the negative charge An electron transporting material is contained therein.

  In an electrophotographic process using an organic electrophotographic photosensitive member, it is generally used with a negative charge, and a normal layer type is generally used from the viewpoint of durability.

  Hereinafter, an electrophotographic photosensitive member having a laminated (normal layer) photosensitive layer used for negative charging will be described.

  As the conductive support used in the present invention, a metal or alloy such as aluminum, nickel, copper, gold, iron, etc., a metal such as aluminum, silver, gold or the like on an insulating support such as polyester, polycarbonate, polyimide, glass or the like Examples thereof include those in which a thin film of a conductive material such as indium oxide and tin oxide is formed, carbon and conductive fillers dispersed in a resin, and conductivity is imparted. 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 chemical treatment with 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.

  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 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 treatment is a method in which a powdery 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. The type, shape, size, hardness, specific gravity, suspension temperature and the like can be controlled. 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 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 made of a conductive metal oxide and a binder resin is applied to a support of aluminum or an aluminum alloy to form a conductive support, a powder made of conductive fine particles is used as a filler in the conductive film. Is contained. In this method, 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, and if necessary, a conductive coating layer is provided on the fine particles with tin oxide or the like to obtain a specific resistance suitable as a filler. The specific resistance of the conductive fine particle powder is preferably 0.1 to 1000 Ωcm, and more preferably 1 to 1000 Ωcm. The content of the filler is preferably 1.0 to 90% by mass, and more preferably 5.0 to 80% by mass with respect to the conductive film layer. The coating layer may contain fluorine or antimony as necessary.

  As the binder resin used in 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 from 0.1 to 30 μm, and more preferably from 0.5 to 20 μm. Further, 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. 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. Further, a leveling agent may be added to enhance the surface property.

  Examples of the charge generating material used in the present invention include (1) azo pigments such as monoazo, disazo and trisazo, (2) phthalocyanine pigments such as metal phthalocyanine and nonmetal phthalocyanine, and (3) indigo compounds such as indigo and thioindigo. Pigments, (4) perylene pigments such as perylene anhydride and perylene imide, (5) polycyclic quinone pigments such as anthraquinone and pyrenequinone, (6) squarylium dyes, (7) pyrylium salts and thiapyrylium salts ( 8) Triphenylmethane dyes, (9) inorganic materials such as selenium, selenium tellurium, amorphous silicon, (10) quinacridone pigments, (11) azulenium salt pigments, (12) cyanine dyes, (13) xanthene dyes, (14) Quinoneimine dye, (15) styryl dye, (16) Cadmium and (17) zinc oxide. In particular, metal phthalocyanine pigments are preferable, and among them, oxytitanium phthalocyanine crystals, chlorogallium phthalocyanine crystals, dichlorotin phthalocyanine crystals, and hydroxygallium phthalocyanine pigments are preferable, and hydroxygallium phthalocyanine pigments are particularly preferable. As the oxytitanium phthalocyanine pigment, oxytitanium having strong peaks at 9.0 °, 14.2 °, 23.9 °, and 27.1 ° of the Bragg angles (2θ ± 0.2 °) in CuKα characteristic X-ray diffraction Phthalocyanine pigment, strong against Bragg angle (2θ ± 0.2 °) of 9.5 °, 9.7 °, 11.7 °, 15.0 °, 23.5 °, 24.1 °, 27.3 ° Oxytitanium phthalocyanine pigments having a peak are preferred. Examples of the chlorogallium phthalocyanine crystal include chlorogallium phthalocyanine crystals having strong diffraction peaks at Bragg angles (2θ ± 0.2 °) of 7.4, 16.6, 25.5, and 28.2 °, Bragg angles (2θ ± Chlorogallium phthalocyanine crystals having strong diffraction peaks at 6.8, 17.3, 23.6, 26.9 ° at 0.2 °), and 8.7, 9 at Bragg angle (2θ ± 0.2 °) A chlorogallium phthalocyanine crystal having a strong diffraction peak at .2, 17.6, 24.0, 27.4, 28.8 ° is preferred. Dichlorotin phthalocyanine crystals include dichlorotin having strong diffraction peaks at Bragg angles (2θ ± 0.2 °) of 8.3, 12.2, 13.7, 15.9, 18.9, 28.2 °. Phthalocyanine crystal, dichlorotin phthalocyanine crystal having a strong diffraction peak at 8.5, 11.2, 14.5, 27.2 ° with a Bragg angle (2θ ± 0.2 °), Bragg angle (2θ ± 0.2 °) 8.7, 9.9, 10.9, 13.1, 15.2, 16.3, 17.4, 21.9, 25.5 °, dichlorotin phthalocyanine crystals having strong diffraction peaks, and A dichlorotin phthalocyanine crystal having strong diffraction peaks at 9.2, 12.2, 13.4, 14.6, 17.0, and 25.3 ° with a Bragg angle (2θ ± 0.2 °) is preferable. As the hydroxygallium phthalocyanine crystal, a hydroxygallium phthalocyanine crystal having strong diffraction peaks at Bragg angles (2θ ± 0.2 °) of 7.3 °, 24.9 °, and 28.1 °, Bragg angle (2θ ± 0. (2 °) is preferably a hydroxygallium phthalocyanine crystal having strong diffraction peaks at 7.5, 9.9, 12.5, 16.3, 18.6, 25.1 and 28.3 °.

  Examples of the binder resin include polymers and copolymers of vinyl compounds such as styrene, vinyl acetate, vinyl chloride, acrylic acid ester, methacrylic acid ester, vinylidene fluoride, and trifluoroethylene, polyvinyl alcohol, polyvinyl acetal, and polycarbonate. Polyester, polysulfone, polyphenylene oxide, polyurethane, cellulose resin, phenol resin, melamine resin, silicon resin, epoxy resin, and the like, but are not limited thereto. Among these, polyester, vinyl acetate, and polyvinyl acetal are preferable, and polyvinyl acetal is more preferable. The molecular weight is preferably Mw = 60,000 to 150,000.

  The film thickness of the charge generation layer is preferably from 0.01 to 2 μm, and more preferably from 0.05 to 0.5 μm. The ratio between the charge generation material and the binder resin in the charge generation layer is preferably 0.5 / 1 to 4/1, and more preferably 1/1 to 3/1.

  And it is desirable to have the said bipyridyl compound. Although there is no restriction | limiting in the addition amount of a bipyridyl compound, it is preferable that it is 1-100% (mass conversion) of a charge generation material, and 10-50% is more preferable. Bipyridyl compounds may be used alone or in combination. Moreover, you may contain an additive for the purpose of improving an electrical property, film formability, etc.

  The charge generation layer is coated and dried after dispersing the pigmented charge generation material together with a binder resin and other compounds using a solvent and a homogenizer, ultrasonic dispersion, ball mill, vibration ball mill, sand mill, attritor and roll mill. Formed. The bipyridyl compound and the binder resin may be added after dispersion.

  The hole transport layer contains a hole transport material in a molecular dispersion state and a binder resin, and a solution in which a binder resin having film formability and the following hole transport material are dissolved is applied. And formed by drying.

  Hole transport materials include polycyclic aromatic compounds such as pyrene and anthracene, heterocyclic compounds such as carbazole, indole, imidazole, oxazole, thiazole, oxadiazole, pyrazole, pyrazoline, thiadiazole and triazole, p-diethylaminobenzaldehyde Hydrazone compounds such as -N, N-diphenylhydrazone and N, N-diphenylhydrazino-3-methylidene-9-ethylcarbazole, α-phenyl-4'-N, N-diaminostilbene and 5- [4- ( Di-p-tolylamino) benzylidene] -5H-dibenzo [a, d] dicycloheptene and other styryl compounds, benzidine compounds, triarylamine compounds, triphenylamine, or a group consisting of these compounds as a main chain. The polymer having the side chain (e.g., poly -N- vinylcarbazole and polyvinyl anthracene, etc.) are mentioned, it is not limited thereto.

  Examples of the resin having a film forming property include, but are not limited to, polyester, polycarbonate, polymethacrylic acid ester, polyarylate, polysulfone, and polystyrene.

  In particular, polycarbonate and polyarylate having a carbonate bond are preferable.

  The ratio between the hole transporting material and the binder resin is preferably 10/2 to 2/10, and more preferably 10/6 to 6/10.

  Furthermore, a surface protective layer may be formed on the hole transport layer. The surface protective layer contains conductive particles or a charge transport material in the binder resin. You may contain additives, such as a lubrication agent. The binder resin itself may have conductivity and charge transport properties. In that case, it is not necessary to include conductive particles / charge transporting substances and the like in addition to the resin. The resin may be a curable resin curable by heat / light / radiation or the like, or a non-curable known thermoplastic resin.

  In the electrophotographic photosensitive member of the present invention, an intermediate layer can be provided on the conductive support. Examples of these materials include polyvinyl alcohol, polyvinyl acetal, polyethylene oxide, ethyl cellulose, methyl cellulose, polyamide, polyamic acid, polyurethane, polyimide, melamine, various metal chelate compounds such as titanium and zirconium, various metal alkoxides, etc. It is not necessarily limited to. In addition, you may have a bipyridyl compound. Bipyridyl compounds may be used alone or in combination. Moreover, you may contain an additive for the purpose of improving an electrical property, film formability, etc. The thickness of the intermediate layer is preferably from 0.1 to 5 μm, more preferably from 0.3 to 3 μm.

  For example, dip coating method, spray coating method, curtain coating method and spin coating method are known as methods for applying these electrophotographic photosensitive member preparation coating solutions. From the viewpoint of efficiency / productivity, A dip coating method is preferred.

  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 a direction indicated by 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 means 5, and the developed toner developed image is transferred between the electrophotographic photosensitive member 1 and the transfer means 6 from a paper supply unit (not shown). The transfer means 6 sequentially transfers the transfer material 7 taken out synchronously with the rotation of 1 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).

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

  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 plurality of components such as the electrophotographic photosensitive member 1, the charging unit 3, the developing unit 5, and the cleaning unit 9 described above are integrally coupled as a process cartridge. The electrophotographic apparatus main body such as a copying machine or a laser beam printer may be detachable.

  For example, at least one of the charging unit 3, the developing unit 5 and the cleaning unit 9 is integrally supported with the electrophotographic photosensitive member 1 to form a cartridge, and the apparatus is used by using a guide unit such as a cartridge insertion guide 11 / rail of the apparatus main body. The process cartridge can be attached to and detached from the main body.

  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. The light is emitted by scanning, driving the LED array, driving the liquid crystal shutter array, and the like.

  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, and further, displays, recordings, light printing, plate making and the like using electrophotographic technology. The present invention can be widely applied to apparatuses such as facsimiles.

  Hereinafter, the present invention will be described in more detail with reference to examples.

Example 1
[Creation of photoconductor]
First, the coating material for conductive layers was prepared by the following procedure. 50 parts of conductive titanium oxide powder coated with tin oxide containing 10% antimony oxide (mass part, the same applies hereinafter), resol type phenol resin (Pryofen J-325, manufactured by Dainippon Ink & Chemicals, Inc.) 25 parts, 20 parts of methyl cellosolve, 5 parts of methanol and 0.002 part of a silicone compound (polydimethylsiloxane polyoxyalkylene copolymer) were prepared by dispersing for 2 hours in a sand mill using φ1 mm glass beads. This paint was applied by dip coating on an aluminum cylinder having a 30φ length of 260 mm and dried at 150 ° C. for 30 minutes to form a conductive layer having a thickness of 15 μm.

  Next, 15 parts of an alcohol-soluble polyamide resin (Amilan CM8000: manufactured by Toray Industries, Inc.) is dissolved in 200 parts of methanol and 150 parts of benzyl alcohol, and this solution is applied onto the conductive layer by a dip coating method. The film was dried at a temperature of 10 ° C. for 10 minutes to form an intermediate layer having a thickness of 0.7 μm.

  Next, a hydroxygallium phthalocyanine pigment having strong peaks at 7.3 °, 24.9 °, and 28.1 ° of the black angle (2θ ± 0.2 °) in CuKα characteristic X-ray diffraction as a charge generating material (CGM) 5 parts, 2.5 parts of polyvinyl butyral (trade name S-REC BX-1, manufactured by Sekisui Chemical Co., Ltd.), 20 parts of tetrahydrofuran and 15 parts of cyclohexanone are mixed with a sand mill using φ1 mm glass beads. After time dispersion, 200 parts of tetrahydrofuran, 100 parts of cyclohexanone, and 1.5 parts of bipyridyl compound E1-11 shown in Table 1 were added to prepare a charge generation layer coating material having an average particle size of 0.18 μm (Horiba) (Measured by centrifugal sedimentation method with CAPA700 manufactured by Seisakusho).

  This paint was applied onto the intermediate layer by a dip coating method and dried at 100 ° C. for 10 minutes to form a charge generation layer having a thickness of 0.18 μm.

  Next, 50 parts of an allylamine compound (21) having the following structural formula as a hole transporting material and an average molecular weight Mw = 100,000 having the following structure (22) (gel permeation chromatography “HLC-” manufactured by Tosoh Corporation) The polyarylate resin (60 parts) is dissolved in 250 parts of monochlorobenzene and 200 parts of tetrahydrofuran, and this solution is applied onto the charge generation layer by the dip coating method. It dried at 60 degreeC for 60 minute (s), the positive hole transport layer with a film thickness of 20 micrometers was formed, and the electrophotographic photoreceptor was obtained.

[Evaluation]
Evaluation was made by changing the above-mentioned electrophotographic photosensitive member into a color laser printer LBP 2510 manufactured by Canon Inc. (primary charging: roller contact DC charging, one component contact development, process speed 94.2 mm / second, variable charging conditions, Trek High-voltage power supply Model 610 manufactured by the company is used.

  Image evaluation and endurance tests were performed by attaching an electrophotographic photosensitive member to a cyan process cartridge. Surface potential was measured by modifying the cartridge and attaching a potential probe (model 6000B-8: manufactured by Trek) to the development position. The measurement was performed using an electrometer (model 344: manufactured by Trek).

  In an environment of 15 ° C / 15% RH, the light intensity was set so that the potential after exposure would be -150V, and after a durability test of 5000 sheets with an image density of 10%, the potential was measured again, and the potential change due to the durability test Was measured.

  After setting the pre-exposure potential / post-exposure potential to −600 V / −150 V again, the ghost image was evaluated in a state where the pre-exposure was turned off. As for the ghost image, as shown in FIG. 2, a solid square image was produced at the head of the image, and then a halftone image of 1 dot and 1 space was created. The order of image creation 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 performed by measuring the density difference between the 1-dot 1-space image density and the image density of the ghost portion with a spectral densitometer X-Rite 504/508 (manufactured by X-Rite Co., Ltd.). The ten points were averaged, and the average of these ten points was taken as one result, and all the above-mentioned ten ghost images were measured in the same manner. Their average value was determined. The results are shown in Table 3. This density difference means that the smaller the value, the better the ghost.

(Examples 2 to 15)
A photoconductor was prepared and evaluated in the same manner as in Example 1 except that the photoconductor formulation shown in Table 3 was used. The results are shown in the table.
Roller (Comparative Example 1)
A photoreceptor was prepared and evaluated in the same manner as in Example 1 except that the bipyrazyl compound (23) shown below was added to the roller charge generation layer and the photoreceptor treatment method shown in Table 3 was used. The results are shown in Table 3.

(Comparative Example 2)
A photoconductor was prepared and evaluated in the same manner as in Example 1 except that the following pyridyl compound (24) was added to the charge generation layer and the photoconductor processing method shown in Table 3 was used. The results are shown in Table 3.

(Examples 16 to 18)
A photoconductor was prepared and evaluated in the same manner as in Example 1 except that the allylamine compound (25) shown below was used as the hole transporting material and the photoconductor processing method shown in Table 3 was used. The results are shown in Table 3.

(Examples 19 to 20)
Replacing the charge generating material with an oxytitanium phthalocyanine pigment having strong peaks at 9.0 °, 14.2 °, 23.9 °, 27.1 ° with a black angle 2θ ± 0.2 ° in CuKα characteristic X-ray diffraction, An electrophotographic photoreceptor was prepared and evaluated in the same manner as in Example 1 except that the photoreceptor processing method shown in Table 3 was used. The results are shown in Table 3.

(Example 21)
A photoconductor was prepared and evaluated in the same manner as in Example 1 except that the bipyridyl compounds listed in Table 3 were added when the intermediate layer coating solution was prepared, and the photoconductor processing method described in Table 3 was used. The results are shown in Table 3.

(Examples 22 to 25)
A photoconductor was prepared and evaluated in the same manner as in Example 21 except that the photoconductor processing method shown in Table 3 was used. The results are shown in Table 3.

(Comparative Example 3)
A photoreceptor was prepared and evaluated in the same manner as in Example 21 except that the compound (24) was added to the intermediate layer and the photoreceptor treatment method shown in Table 3 was used. The results are shown in Table 3.

(Comparative Example 4)
A photoconductor was prepared and evaluated in the same manner as in Example 1 except that no bipyridyl compound was added and the photoconductor processing method shown in Table 3 was used. The results are shown in Table 3.

1 is a diagram illustrating 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 a figure explaining the printing for ghost evaluation used in the case of ghost image evaluation.

Explanation of symbols

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

Claims (4)

An electrophotographic photoreceptor comprising any compound represented by the following structural formulas (1) to (6).

In formulas (1) to (6), X ₁ and X ₂ are O, C (CN) R, C (CN) COR, C (CN) COOR, C (COOR) ₂ , CHR or NR, (R is Substituted or unsubstituted aromatic group, substituted or unsubstituted aliphatic group or cyano group).
In formulas (1) to (6), R _{1 to} R ₆ are a substituted or unsubstituted aromatic group, a substituted or unsubstituted aliphatic group, an alkoxy group, an ester group, a nitro group, a cyano group, a halogen atom, or a hydrogen atom. Indicates. An electrophotographic photoreceptor comprising any compound represented by the following structural formulas (7) to (16).

In the formulas (7) to (16), X ₁ is O, C (CN) R, C (CN) COR, C (CN) COOR, C (COOR) ₂ , CHR or NR, (R is substituted or unsubstituted An aromatic group, a substituted or unsubstituted aliphatic group or a cyano group).
In formulas (7) to (16), R _{1 to} R ₆ are a substituted or unsubstituted aromatic group, a substituted or unsubstituted aliphatic group, an alkoxy group, an ester group, a nitro group, a cyano group, a halogen atom, or a hydrogen atom. Indicates.   3. The electrophotographic photosensitive member according to claim 1 and at least one means selected from the group consisting of a charging means, a developing means and a cleaning means are integrally supported and detachably attached to the main body of the electrophotographic apparatus. Process cartridge characterized by being.   An electrophotographic apparatus comprising the electrophotographic photosensitive member according to claim 1, a charging unit, an exposure unit, a developing unit, and a transfer unit.