JP5656664B2 - Electrophotographic photosensitive member, process cartridge, electrophotographic apparatus, and method of manufacturing electrophotographic photosensitive member - Google Patents

Description

  The present invention relates to an electrophotographic photosensitive member, a process cartridge, an electrophotographic apparatus, and a method for manufacturing an electrophotographic photosensitive member.

  As an electrophotographic photosensitive member mounted on an electrophotographic apparatus, an intermediate layer on an electroconductive support, an organic charge generating material (organic photoconductive material) formed on the intermediate layer, and a charge transport material There is an organic electrophotographic photosensitive member (hereinafter simply referred to as an “electrophotographic photosensitive member”) having a photosensitive layer containing. The intermediate layer has a charge blocking function, and serves to suppress the generation of image defects such as black spots by suppressing the injection of holes from the conductive support to the photosensitive layer side. Patent Document 1 proposes an electrophotographic photosensitive member having an intermediate layer containing an amine compound between a support and a photosensitive layer, and suppressing the occurrence of black spots.

  However, if the electrical resistance of the intermediate layer is too high, electrons generated in the photosensitive layer stay in the photosensitive layer, causing ghosting. Therefore, the electrical resistance value of the intermediate layer needs to be reduced to some extent, and it is required to achieve both improvement of ghost and suppression of black spots. In particular, in recent years, high image quality represented by colorization has been promoted, and it is required to improve ghost and black spot at a higher level.

  In order to achieve both improvement of ghost and suppression of black spots, a method in which a plurality of intermediate layers contain metal oxide particles and a silane coupling agent has been performed. Patent Document 2 proposes an electrophotographic photosensitive member in which an intermediate layer containing no metal oxide particles and an intermediate layer containing metal oxide particles and a binder resin are sequentially laminated on a conductive support. In Patent Document 3, an electrophotographic photoreceptor in which a silane coupling agent-containing layer containing a silane coupling agent at a higher concentration than the intermediate layer is provided between the intermediate layer containing metal oxide particles and the photosensitive layer. Proposed.

JP-A-01-283571 JP 2006221115 A JP 2008-066511 A

  However, even in the intermediate layer using any of the above amine compounds, metal oxide particles, and silane coupling agents, improvement in ghost and suppression of black spots cannot be achieved at a high level.

  An object of the present invention is to provide an electrophotographic photosensitive member having an intermediate layer in which improvement of ghost and suppression of black spots are compatible at a high level.

  Another object of the present invention is to provide a process cartridge and an electrophotographic apparatus having the electrophotographic photosensitive member. Another object of the present invention is to provide a method for producing an electrophotographic photosensitive member for producing the electrophotographic photosensitive member.

The above object is achieved by the present invention described below.
That is, the present invention is formed on a conductive support, a first intermediate layer formed on the conductive support, a second intermediate layer formed on the first intermediate layer, and the second intermediate layer. In an electrophotographic photoreceptor having a photosensitive layer,
The first intermediate layer is
Metal oxide particles ,
At least one amine compound selected from the group consisting of a compound represented by the following formula (1), a compound represented by the following formula (2), and a polymer represented by the following formula (2) ;
Including
The content of the amine compound in the first intermediate layer is 1% by mass or more and 15% by mass or less with respect to the metal oxide particles in the first intermediate layer.
The second intermediate layer relates to an electrophotographic photosensitive member characterized by containing metal oxide particles and not containing the amine compound.

Wherein ^{(1), X 11, X} 12, X 13 are each independently a hydrogen atom, 2 to 4 of the alkyl group with a carbon number or carbon atoms showed 2 to 4 hydroxyalkyl ^{group, X 11} , X ¹² and X ¹³ are each an alkyl group having 2 to 4 carbon atoms or a hydroxyalkyl group having 2 to 4 carbon atoms. In formula (2), R ²¹ and R ²⁴ each independently represent a hydrogen atom, a methyl group, or an ethyl group. R ²² and R ²³ each independently represent a hydrogen atom or a methyl group. Carbon number in Formula (2) is 2-4.

  Further, the present invention integrally supports the electrophotographic photosensitive member and at least one means selected from the group consisting of a charging means, a developing means, a transfer means, and a cleaning means, and is detachable from the electrophotographic apparatus main body. The present invention relates to a process cartridge.

  The present invention also relates to an electrophotographic apparatus comprising the electrophotographic photosensitive member, a charging unit, an exposing unit, a developing unit, and a transfer unit.

Further, the present invention is a method for producing the electrophotographic photoreceptor,
A coating solution for the first intermediate layer containing the metal oxide particles and the amine compound is applied onto the conductive support to form a coating film, and the coating film of the coating solution for the first intermediate layer is dried. A first step of forming the first intermediate layer;
A second intermediate layer coating solution containing the metal oxide particles and not containing the amine compound is applied onto the first intermediate layer to form a coating film, and the coating film of the second intermediate layer coating solution is dried. And a second step of forming the second intermediate layer. The present invention relates to a method for manufacturing an electrophotographic photosensitive member.

  According to the present invention, it is possible to provide an electrophotographic photosensitive member that achieves both improvement in ghost and suppression of black spots at a high level. In addition, according to the present invention, a process cartridge and an electrophotographic apparatus having the electrophotographic photosensitive member can be provided. Moreover, according to this invention, the manufacturing method of the electrophotographic photoreceptor which manufactures the said electrophotographic photoreceptor can be provided.

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 for demonstrating the layer structure of the electrophotographic photoreceptor of this invention. It is a figure for demonstrating the printing for ghost evaluation used in the case of ghost image evaluation. It is a figure for demonstrating the image pattern of 1 dot Keima pattern.

  The layer structure of the electrophotographic photosensitive member used in the present invention includes a conductive support, a first intermediate layer formed on the conductive support, a second intermediate layer formed on the first intermediate layer, and the The photosensitive layer is formed on the second intermediate layer.

  The electrophotographic photoreceptor of the present invention includes a first intermediate layer coating solution containing metal oxide particles and the above-described amine compound, and a second intermediate layer coating containing metal oxide particles and not including the above-described amine compound. Manufactured using liquid. And the 1st process of apply | coating the coating liquid for 1st intermediate | middle layers on an electroconductive support body, drying this, and forming the 1st intermediate | middle layer, Application | coating for 2nd intermediate | middle layers on a 1st intermediate | middle layer The electrophotographic photoreceptor of the present invention can be produced by the second step of applying the solution and drying it to form the second intermediate layer.

  The photosensitive layer is mainly composed of a single layer type photosensitive layer containing a hole transport material and a charge generation material in the same layer, a charge generation layer containing a charge generation material, and a hole containing a hole transport material. And a laminated type (functional separation type) photosensitive layer separated into a transport layer. In the present invention, a laminated photosensitive layer is preferred.

  An outline of a preferred structure of the electrophotographic photosensitive member in the present invention is shown in FIG. In the electrophotographic photosensitive member shown in FIG. 2, a first intermediate layer 22 on a conductive support 21, a second intermediate layer 23 on a first intermediate layer, a charge generation layer 24 on a second intermediate layer, and charge generation. A hole transport layer 25 is laminated on the layer. Moreover, you may provide a protective layer on a positive hole transport layer as needed.

  The first intermediate layer and the second intermediate layer of the present invention are provided between the conductive support and the photosensitive layer. Since the first intermediate layer and the second intermediate layer have the following configurations, both improvement in ghost and suppression of black spots can be achieved at a high level.

  The first intermediate layer contains metal oxide particles and an amine compound, and the amine compound is at least a compound represented by the formula (1) or the formula (2) or a polymer of the compound represented by the formula (2). It is a kind. The content of the amine compound is 1% by mass or more and 15% by mass or less with respect to the metal oxide particles in the first intermediate layer. The second intermediate layer contains metal oxide particles and does not contain the amine compound.

  The inventors presume the reason why the electrophotographic photosensitive member of the present invention achieves both improvement of ghost and suppression of black spots at a high level as follows.

  The ghost is considered to be related to the electric field strength and the residual charge amount in the photosensitive layer (charge generation layer). In a bright part where the surface potential of the photoconductor is exposed to a low level, the electric field strength inside the photoconductor becomes weak and the residual charge in the photoconductive layer (charge generation layer) increases. A ghost phenomenon occurs when the influence of the next charging cannot be ignored. In black spots, it is considered that hole injection occurs from the conductive support side to the photosensitive layer (charge generation layer) when the electric field strength is high.

  By containing the amine compound of the present invention in the first intermediate layer and not in the second intermediate layer, charge (hole, electron) transfer can be adjusted. That is, in the second intermediate layer containing metal oxide particles and not containing an amine compound, electron transfer from the photosensitive layer to the conductive support tends to occur, and the residual charge in the photosensitive layer can be reduced. On the other hand, in the first intermediate layer containing an amine compound, the injection of holes from the conductive support to the photosensitive layer side is blocked by the amine compound, thereby suppressing the occurrence of black spots. Furthermore, the amine compound in the first intermediate layer is contained in an amount of 1% by mass to 15% by mass with respect to the metal oxide particles in the first intermediate layer. Thereby, it is considered that residual charges in the first intermediate layer and at the interface between the first intermediate layer and the second intermediate layer are reduced, and the block of hole injection from the conductive support side is made compatible. Thus, it is considered that there is an excellent effect in achieving both improvement of ghost and suppression of black spots.

  In addition, when the amine compound is contained in the second intermediate layer, the electron transfer from the photosensitive layer to the conductive support side is blocked, and the residual charge increases in the photosensitive layer. It is thought that it cannot be obtained. In the case where the first intermediate layer does not contain an amine compound, it is considered that hole injection from the conductive support to the photosensitive layer side is not blocked and the effect of suppressing black spots cannot be sufficiently obtained.

  In this invention, content of the amine compound in a 1st intermediate | middle layer is 1 to 15 mass% with respect to the metal oxide particle in a 1st intermediate | middle layer. If it is 1% by mass or more, hole injection from the conductive support to the photosensitive layer side can be sufficiently blocked, and the effect of suppressing black spots can be sufficiently obtained. On the other hand, in the case of the first intermediate layer in which the second intermediate layer exists between the photosensitive layer and the amount of the amine compound is up to 15% by mass, blocking of electron transfer due to the inclusion of the amine compound can be suppressed. Residual charges are suppressed, and a ghost improvement effect is obtained.

  The content of the amine compound is more preferably 3% by mass or more and 5% by mass or less with respect to the metal oxide particles in the first intermediate layer, since an excellent ghost improvement effect can be obtained.

  The amine compound of the present invention will be described. The amine compound of the present invention is at least one of a compound represented by the following formula (1), a compound represented by the following formula (2), and a polymer of a compound represented by the following formula (2).

Wherein ^{(1), X 11, X} 12, X 13 are each independently a hydrogen atom, 2 to 4 of the alkyl group with a carbon number or carbon atoms showed 2 to 4 hydroxyalkyl ^{group, X 11} , X ¹² and X ¹³ are each an alkyl group having 2 to 4 carbon atoms or a hydroxyalkyl group having 2 to 4 carbon atoms. In formula (2), R ²¹ and R ²⁴ each independently represent a hydrogen atom, a methyl group, or an ethyl group. R ²² and R ²³ each independently represent a hydrogen atom or a methyl group. Carbon number in Formula (2) is 2-4.

  The compound represented by the formula (1) is preferably a secondary amine or a tertiary amine because a compound having strong basicity is desirable for blocking holes. More preferred is triethanolamine.

  Specific examples of the compound represented by the above formula (1) or the above formula (2) are shown below.

  Next, specific examples of the polymer of the compound represented by the formula (2) will be shown.

  In Table 2, polyethyleneimine is an ethyleneimine polymer of exemplary compound (2-1), polypropyleneimine is a propyleneimine polymer of exemplary compound (2-2), and polybutyleneimine is exemplary compound (2- 3) 1,2-butyleneimine polymer. Among these, polyethyleneimine is preferable.

  In the present invention, in order to effectively transfer electrons from the photosensitive layer to the conductive support, it is preferable not to contain an amine compound having a functional group having 5 or more carbon atoms in the first intermediate layer and the second intermediate layer. .

The first intermediate layer and the second intermediate layer in the present invention contain metal oxide particles. Examples of the metal oxide particles include tin oxide (SnO ₂ ), titanium oxide (TiO ₂ ), zinc oxide (ZnO), zirconium oxide (ZrO), and aluminum oxide (Al ₂ O ₃ ). Among these, it is preferable to use particles of tin oxide, titanium oxide, and zinc oxide.

  In the present invention, the volume average particle size of the metal oxide particles contained in the second intermediate layer is preferably 1 nm or more and 9 nm or less. When the thickness is 9 nm or less, the surface area of the metal oxide particles increases on the photosensitive layer interface side of the second intermediate layer, and the second intermediate layer can easily receive electrons from the photosensitive layer, and electrons move in the second intermediate layer. By securing the degree sufficiently, the effect of improving the ghost is more obtained, which is preferable. In the present invention, the method for measuring the volume average particle size of the metal oxide particles contained in the second intermediate layer is as follows.

  Elemental analysis, such as XMA (X-ray microanalyzer) attached to SEM, and 1 to 100 nm metal oxide particles in the cross-sectional photograph of the second intermediate layer taken at a magnification of 100,000 times by SEM (scanning microscope) Contrasting cross-sectional photographs mapped by element of metal oxide particles by means. Next, the projected area of 100 primary particles of metal oxide particles was measured, and the equivalent diameter of a circle equal to the measured projected area of each metal oxide particle was determined as the diameter of each metal oxide particle. Based on the result, the volume average particle size of the metal oxide particles was calculated.

  In the present invention, the resin used for the first intermediate layer is preferably a resin that is insoluble in the coating solvent for the second intermediate layer so that the amine compound of the present invention is not mixed into the second intermediate layer. In particular, butyral resin, phenol resin, phenol-formaldehyde resin, melamine resin, urethane resin, and epoxy resin are preferable.

  In the present invention, the resin used for the second intermediate layer is polyamide, polyimide, polyamideimide, polyamic acid, polyolefin, polystyrene, styrene-acrylic copolymer, acrylic resin, polymethacrylate, polyvinyl alcohol, polyvinyl acetal, polyvinyl butyral, Examples include polyvinyl formal, polyacrylonitrile, polyacrylamide, alkyd resin, alkyd-melamine resin, and urethane resin.

  In the present invention, the first intermediate layer coating solution for forming the first intermediate layer is obtained by dispersing the metal oxide particles and the amine compound of the present invention together with a resin and a solvent. The first intermediate layer of the electrophotographic photoreceptor of the present invention can be formed by applying the first intermediate layer coating solution obtained by this method and drying it. Examples of the dispersion method include a method using a homogenizer, an ultrasonic disperser, a ball mill, a sand mill, a roll mill, a vibration mill, an attritor, and a liquid collision type high-speed disperser.

  Examples of the solvent used in the first intermediate layer coating solution include alcohol solvents, sulfoxide solvents, ketone solvents, ether solvents, ester solvents, aliphatic halogenated hydrocarbon solvents, and aromatic hydrocarbon solvents.

  Further, the first intermediate layer of the electrophotographic photoreceptor of the present invention may contain organic resin fine particles and a leveling agent as necessary. The film thickness of the first intermediate layer is preferably 0.5 μm or more and 40 μm or less, and more preferably 5 μm or more and 40 μm or less from the viewpoint of covering the surface defects of the conductive support. In particular, it is more preferably 10 μm or more and 20 μm or less.

  In the present invention, the second intermediate layer coating solution for forming the second intermediate layer is obtained by dispersing metal oxide particles together with a resin and a solvent. Or it is good also considering the liquid obtained by adding the liquid which melt | dissolved resin in the sol solution of a metal oxide particle as a coating liquid for 2nd intermediate | middle layers. The second intermediate layer of the electrophotographic photoreceptor of the present invention can be formed by applying the second intermediate layer coating solution obtained by these methods and drying it. Examples of the dispersion method include a method using a homogenizer, an ultrasonic disperser, a ball mill, a sand mill, a roll mill, a vibration mill, an attritor, and a liquid collision type high-speed disperser.

  Examples of the solvent used in the coating solution for the second intermediate layer include alcohol solvents, sulfoxide solvents, ketone solvents, ether solvents, ester solvents, aliphatic halogenated hydrocarbon solvents, and aromatic hydrocarbon solvents.

  Further, the second intermediate layer of the electrophotographic photosensitive member of the present invention may contain organic resin fine particles and a leveling agent as necessary. The film thickness of the second intermediate layer is preferably 0.5 μm or more and 5 μm or less, and more preferably 0.6 μm or more and 3 μm or less.

  It is necessary to appropriately select the drying conditions so that the amine compound of the present invention is contained in the film when the first intermediate layer is formed. That is, it is preferable to form the first intermediate layer at a drying temperature lower than the boiling point of the amine compound.

[Conductive support]
Examples of the conductive support used in the present invention include metals, alloys such as aluminum, nickel, copper, iron, gold, and stainless steel. In addition, a polyester or polycarbonate insulating support formed by forming a thin film of a metal such as aluminum, silver or gold or a conductive material such as indium oxide or tin oxide. In addition, a support in which conductive particles such as carbon black, tin oxide particles, titanium oxide particles, and silver particles are impregnated in a resin, or a plastic having a conductive binder resin can also be used. Examples of the shape of the conductive support include a cylindrical shape and a belt shape, and a cylindrical shape is preferable.

  In order to suppress interference fringes, it is preferable that the surface of the conductive support is moderately roughened. Specifically, it is preferable to use a conductive support obtained by subjecting the conductive support to a treatment such as honing, blasting, cutting, and electric field polishing.

(Photosensitive layer)
In the electrophotographic photoreceptor of the present invention, a photosensitive layer is formed on the second intermediate layer. The photosensitive layer may be any of the above-mentioned single-layer type photosensitive layer and laminated type photosensitive layer, and in the present invention, a laminated type photosensitive layer is preferable. In the laminated photosensitive layer, a charge generation material is dispersed together with a binder resin and a solvent to prepare a charge generation layer coating solution. The charge generation layer can be formed by applying a coating solution for charge generation layer on the second intermediate layer and drying it. Further, a hole transport material is dispersed together with a binder resin and a solvent to prepare a hole transport layer coating solution, and the hole transport layer coating solution is applied onto the charge generation layer and dried to correct the solution. A hole transport layer can be formed.

  Examples of the charge generating material used in the photosensitive layer and the charge generating layer of the electrophotographic photoreceptor of the present invention include azo pigments, phthalocyanine pigments, indigo pigments, perylene pigments, polycyclic quinone pigments, squarylium dyes, pyrylium salts, thiapyrylium salts, Examples include organic photoconductive substances such as phenylmethane dyes, quinacridone pigments, azurenium salt pigments, cyanine dyes, anthanthrone pigments, pyranthrone pigments, xanthene dyes, quinoneimine dyes, and styryl dyes. Among these charge generation materials, phthalocyanine pigments and azo pigments are preferable from the viewpoint of sensitivity. These charge generation materials may be used alone or in combination of two or more.

  In the laminated photosensitive layer, the binder resin used in the charge generation layer of the present invention includes acrylic resin, allyl resin, alkyd resin, epoxy resin, diallyl phthalate resin, silicone resin, styrene-butadiene copolymer, phenol resin, butyral resin. , Benzal resin, polyacrylate, polyacetal, polyamideimide, polyamide, polyallyl ether, polyarylate, polyimide, polyurethane, polyester, polyethylene, polycarbonate, polystyrene, polysulfone, polyvinyl acetal, polybutadiene, polypropylene, methacrylic resin, urea resin, vinyl chloride -Vinyl acetate copolymers, vinyl acetate resins, vinyl chloride resins. More preferred is a butyral resin. These can be used singly or in combination of two or more as a mixture or copolymer.

  The thickness of the charge generation layer is preferably from 0.01 μm to 5 μm, and more preferably from 0.1 μm to 2 μm. In addition, various sensitizers, antioxidants, ultraviolet absorbers, and plasticizers can be added to the charge generation layer as necessary.

  Examples of the dispersion method include a method using a homogenizer, an ultrasonic disperser, a ball mill, a sand mill, a roll mill, a vibration mill, an attritor, and a liquid collision type high-speed disperser. The ratio of the charge generation material to the binder resin is preferably 0.3 parts by mass or more and 4 parts by mass or less for the binder resin with respect to 1 part by mass of the charge generation material.

  Examples of the solvent used for the charge generation layer coating solution include alcohol solvents, sulfoxide solvents, ketone solvents, ether solvents, ester solvents, aliphatic halogenated hydrocarbon solvents, and aromatic hydrocarbon solvents.

  The hole transport materials used in the photosensitive layer and hole transport layer of the electrophotographic photoreceptor of the present invention are triarylamine compounds, hydrazone compounds, styryl compounds, stilbene compounds, pyrazoline compounds, oxazole compounds, triallylmethane Compounds, thiazole compounds and the like. Only one type of hole transport material may be used, or two or more types may be used.

  In the multilayer photosensitive layer, the binder resin used for the hole transport layer is acrylic resin, acrylonitrile resin, allyl resin, alkyd resin, epoxy resin, silicone resin, phenol resin, phenoxy resin, polyacrylamide, polyamideimide, polyamide , Polyallyl ether, polyarylate, polyimide, polyurethane, polyester, polyethylene, polycarbonate, polysulfone, polyphenylene oxide, polybutadiene, polypropylene, methacrylic resin and the like. In particular, polyarylate and polycarbonate are preferable. These may be used alone or in combination as a mixture or copolymer.

  The ratio of the hole transport material to the binder resin is preferably 0.3 parts by mass or more and 10 parts by mass or less of the hole transport material with respect to 1 part by mass of the binder resin. In addition, an antioxidant, an ultraviolet absorber, a plasticizer, and the like can be added to the hole transport layer as necessary. Moreover, you may contain the fine particle comprised by fluorine atom containing resin, silicone containing resin, and these resin. Further, metal oxide particles and inorganic fine particles may be contained.

  The thickness of the hole transport layer is preferably 5 μm or more and 40 μm or less, and more preferably 10 μm or more and 35 μm or less.

  When applying the coating solution for each of the above layers, for example, a coating method such as a dip coating method (a dip coating method), a spray coating method, a spinner coating method, a roller coating method, a Meyer bar coating method, a blade coating method, etc. Can do.

[Electrophotographic equipment]
FIG. 1 shows an example of a schematic configuration of an electrophotographic apparatus provided with a process cartridge having the electrophotographic photosensitive member of the present invention.

  In FIG. 1, reference numeral 1 denotes a cylindrical electrophotographic photosensitive member, which is driven to rotate at a predetermined peripheral speed in the direction of an arrow about an axis 2. The surface of the electrophotographic photoreceptor 1 is uniformly charged to a predetermined negative potential by the charging means 3 during the rotation process. Next, exposure light (image exposure light) 4 output from exposure means (not shown) such as slit exposure or laser beam scanning exposure, which is reflected light from the original, is received. In this way, electrostatic latent images corresponding to target image information are sequentially formed on the surface of the electrophotographic photoreceptor 1. The voltage applied to the charging means 3 may be either a voltage obtained by superimposing an AC component on a DC component or a voltage containing only a DC component.

  The electrostatic latent image formed on the surface of the electrophotographic photoreceptor 1 is developed by reversal development with toner contained in the developer of the developing unit 5 to become a toner image. Next, the toner image formed and supported on the surface of the electrophotographic photosensitive member 1 is sequentially transferred onto the transfer material P by the transfer bias from the transfer unit 6. The transfer material P is taken out from the transfer material supply means (not shown) in synchronism with the rotation of the electrophotographic photosensitive member 1 and fed between the electrophotographic photosensitive member 1 and the transfer means 6 (contact portion). The Further, a bias voltage having a polarity opposite to the charge held in the toner is applied to the transfer means 6 from a bias power source (not shown). The transfer material P that has received the transfer of the toner image is separated from the surface of the electrophotographic photosensitive member 1 and conveyed to the fixing means 8 and undergoes a fixing process of the toner image. It is conveyed to.

  The surface of the electrophotographic photosensitive member 1 after the transfer of the toner image is cleaned by receiving a developer remaining after transfer (transfer residual toner) by the cleaning means 7. Further, after being subjected to charge removal processing by pre-exposure light 11 from a pre-exposure means (not shown), it is repeatedly used for image formation. As the transfer means, an intermediate transfer type transfer means using an intermediate transfer body such as a belt shape or a drum shape may be employed.

  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 7 are selected, and these are stored in a container and integrally supported as a process cartridge. May be configured. The 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, the electrophotographic photosensitive member 1, the charging unit 3, the developing unit 5 and the cleaning unit 7 are integrally supported to form a cartridge, and the electrophotographic apparatus main body is guided to the electrophotographic apparatus main body using the guide unit 10 such as a rail of the electrophotographic apparatus main body. A removable process cartridge 9 can be obtained.

  Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples. In the examples, “part” means “part by mass”.

Example 1
An aluminum cylinder (JIS-A3003) having a diameter of 30 mm and a length of 260.5 mm was used as a conductive support.

  Next, the first intermediate layer was formed by the following method. Zinc oxide (trade name: MZ-150, manufactured by Teika Co., Ltd.) 60 parts, triethanolamine 1.8 parts, blocked isocyanate (trade name: Sumidur 3175, manufactured by Sumitomo Bayern Urethane Co., Ltd.) 13.5 parts, butyral 10 parts of resin (trade name: BM-1, manufactured by Sekisui Chemical Co., Ltd.) and 90 parts of methyl ethyl ketone were mixed. Next, 57 parts of this solution was subjected to a dispersion treatment for 2 hours in a sand mill using glass beads having a diameter of 1 mm. As a catalyst, 0.005 part of dioctyltin dilaurate was added to 100 parts of the resulting dispersion to prepare a first intermediate layer coating liquid. This first intermediate layer coating solution was dip-coated on a conductive support and dried at 170 ° C. for 40 minutes to form a first intermediate layer having a thickness of 15 μm.

  Next, a second intermediate layer was formed by the following method. Dissolve 0.2 mol (56 parts) of stannic chloride pentahydrate in 200 ml of water, and add 28% by mass of ammonia water while stirring to obtain a slurry containing white tin oxide fine particles having a pH of 1.5. It was. The obtained tin oxide fine particle-containing slurry is heated to a temperature of 70 ° C., then naturally cooled to a temperature of around 50 ° C., and pure water is added to obtain a 1 L tin oxide fine particle-containing slurry, and solid-liquid separation is performed using a centrifuge. It was. After adding 800 ml of pure water to this water-containing solid content and dispersing with a homogenizer, washing was performed by solid-liquid separation using a centrifuge. 75 ml of pure water was added to the water-containing solid content after washing to prepare a tin oxide fine particle-containing slurry. The obtained tin oxide fine particle-containing slurry was added with 0.5 parts of an aqueous ammonia solution as a dispersion stabilizer and stirred. When the slurry became transparent, the temperature was raised to 70 ° C., and then naturally cooled to obtain a solid content concentration of 20 mass. % Tin oxide sol solution was obtained. 13.5 parts of blocked isocyanate (trade name: Sumijour 3175, manufactured by Sumitomo Bayern Urethane Co., Ltd.), 10 parts of butyral resin (trade name: BM-1, manufactured by Sekisui Chemical Co., Ltd.), and 90 parts of methyl ethyl ketone, the oxidation The tin sol solution was mixed thoroughly. Then, 0.005 part of dioctyltin dilaurate as a catalyst was added to 100 parts of the obtained mixed liquid to prepare a coating solution for the second intermediate layer. This second intermediate layer coating solution was dip-coated on the first intermediate layer and dried at 170 ° C. for 40 minutes to form a second intermediate layer having a thickness of 1 μm.

  Next, the Bragg angles (2θ ± 0.2 °) in CuKα characteristic X-ray diffraction are 7.5 °, 9.9 °, 16.3 °, 18.6 °, 25.1 °, and 28.3 °. A crystalline form of hydroxygallium phthalocyanine crystal having a strong peak was prepared. It was mixed with 5 parts of polyvinyl butyral (trade name: ESREC BX-1, manufactured by Sekisui Chemical Co., Ltd.) and 250 parts of cyclohexanone, and dispersed in a sand mill using glass beads having a diameter of 1 mm for 1 hour. After the dispersion treatment, 250 parts of ethyl acetate was added to prepare a charge generation layer coating solution. The charge generation layer coating solution was dip-coated on the second intermediate layer and dried at 100 ° C. for 10 minutes to form a charge generation layer having a thickness of 0.16 μm.

  Next, 8 parts of an amine compound having a structure represented by the following formula (4), 1 part of an amine compound having a structure represented by the following formula (5), and a polyarylate having a structural unit represented by the following formula (6) A coating solution for hole transport was prepared by dissolving 10 parts (weight average molecular weight Mw: 110000) in a solvent having a final weight ratio of monochlorobenzene: dimethoxymethane of 7: 3. This hole transport coating solution was dip-coated on the charge generation layer and dried at a temperature of 120 ° C. for 1 hour to form a hole transport layer having a thickness of 18 μm. In this way, two electrophotographic photoreceptors having a first intermediate layer, a second intermediate layer, a charge generation layer, and a hole transport layer were produced.

  For one electrophotographic photoreceptor, a cross-sectional photograph of the second intermediate layer was taken with an SEM, and 100 or more primary particles of metal oxide particles were measured to obtain a volume average particle size. As a result, the volume average particle diameter was 9 nm.

(Examples 2 to 12)
The electrophotographic photoreceptor in the same manner as in Example 1 except that the type and content of the amine compound and metal oxide particles in the first intermediate layer coating solution were changed as shown in Table 3. Manufactured. As the type of metal oxide particles, tin oxide (NanoTek SnO _2, manufactured by C.I. Kasei), or titanium oxide (CREL, manufactured by Ishihara Sangyo Kaisha).

(Examples 13 to 17)
In Example 1, the electrophotographic photoreceptor was prepared in the same manner as in Example 1 except that the type and content of the amine compound and metal oxide particles in the first intermediate layer coating solution were changed as shown in Table 3. Manufactured.

(Examples 18 to 29)
In Example 1, the electrophotographic photoreceptor was prepared in the same manner as in Example 1 except that the type and content of the amine compound and metal oxide particles in the first intermediate layer coating solution were changed as shown in Table 3. Manufactured.

(Examples 30 to 59)
In Example 1, the types and contents of the amine compound and metal oxide particles in the first intermediate layer coating solution were changed as shown in Table 4. Next, 60 parts of zinc oxide (trade name: MZ-150, manufactured by Teica), 13.5 parts of blocked isocyanate (trade name: Sumidur 3175, manufactured by Sumitomo Bayern Urethane Co., Ltd.), 10 parts of butyral resin (trade name: BM-1, manufactured by Sekisui Chemical Co., Ltd.) and 120 parts of methyl ethyl ketone were mixed. Next, 57 parts of this mixed solution was subjected to a dispersion treatment for 2 hours in a sand mill using glass beads having a diameter of 1 mm. As a catalyst, 0.005 part of dioctyltin dilaurate was added to 100 parts of the resulting dispersion to prepare a coating solution for the second intermediate layer. This second intermediate layer coating solution was dip-coated on the first intermediate layer and dried at 170 ° C. for 40 minutes to form a second intermediate layer having a thickness of 1 μm. Otherwise, an electrophotographic photoreceptor was produced in the same manner as in Example 1. A cross-sectional photograph of the second intermediate layer was taken with an SEM, and 100 or more primary particles of metal oxide particles were measured to obtain a volume average particle size. As a result, the volume average particle size was 35 nm.

(Comparative Example 1)
An electrophotographic photosensitive member was produced in the same manner as in Example 1 except that the amine compound was not contained in the first intermediate layer.

(Comparative Example 2)
An electrophotographic photoreceptor was prepared in the same manner as in Example 1 except that 0.1 mass% of the exemplified compound (1-4) was contained in the first intermediate layer with respect to the metal oxide particles in the first intermediate layer. Manufactured.

(Comparative Example 3)
An electrophotographic photoreceptor was produced in the same manner as in Example 1 except that the first intermediate layer contained 16% by mass of the exemplary compound (1-4) with respect to the metal oxide particles in the first intermediate layer. .

(Comparative Example 4)
An electrophotographic photosensitive member was produced in the same manner as in Example 1, except that 25% by mass of the exemplified compound (1-4) was contained in the first intermediate layer with respect to the metal oxide particles in the first intermediate layer. .

(Comparative Example 5)
Example 1 except that the first intermediate layer does not contain an amine compound and the second intermediate layer contains 5% by mass of the exemplified compound (1-4) with respect to the metal oxide particles in the second intermediate layer. In the same manner as in Example 1, an electrophotographic photosensitive member was produced.

(Comparative Example 6)
Except that the exemplified compound (1-4) was contained in the first intermediate layer in an amount of 3% by mass with respect to the metal oxide particles in the first intermediate layer, and the second intermediate layer was not provided, the same as in Example 1. Thus, an electrophotographic photosensitive member was produced.

(Comparative Examples 7 to 10)
In the first intermediate layer, methylamine in Comparative Example 7, pentylamine in Comparative Example 8, 1,1-pentylimine in Comparative Example 9, polypentyleneimine in Comparative Example 10, and metal oxidation in the first intermediate layer, respectively. An electrophotographic photosensitive member was produced in the same manner as in Example 1 except that 3% by mass was contained with respect to the product particles. Note that methylamine, pentylamine, 1,1-pentylimine, and polypentyleneimine are amine compounds that are not represented by formula (1) or formula (2) of the present invention.

(Comparative Example 11)
An electrophotographic photosensitive member was produced in the same manner as in Example 1 except that the first intermediate layer was not provided and the second intermediate layer was provided on the conductive support.

  In Tables 3 and 4, the content of the exemplified compound represents the content ratio (% by mass) relative to the metal oxide particles in the first intermediate layer.

(Evaluation)
The evaluation methods for the electrophotographic photoreceptors of Examples 1 to 59 and Comparative Examples 1 to 10 are as follows.

  As an evaluation apparatus, a laser beam printer LaserJet 4700 manufactured by Hewlett-Packard was used. At the temperature of 22.5 ° C. and humidity of 50% RH, the manufactured electrophotographic photosensitive member is mounted on the cyan process cartridge, and is mounted on the cyan process cartridge station. The image after durability was evaluated. The drum surface potential was set such that the initial dark portion potential was −500 V and the initial bright portion potential was −170 V. The surface potential of the electrophotographic photosensitive member is measured by modifying the cartridge, attaching a potential probe (model 6000B-8, manufactured by Trek Japan) to the developing position, and measuring the potential at the center of the drum with a surface potential meter (model 344, Trek (Manufactured by Japan). When passing through a character image with a printing rate of 2% for each color, a full color print operation is performed in intermittent mode in which one letter paper is output every 20 seconds, and 5000 images are output without turning on pre-exposure. It was. Then, at the start of evaluation and at the end of 5000 sheets, one solid white image is output as the first sheet, and then a ghost evaluation print (as shown in FIG. 3, in the white background (white image) at the top of the image) After producing a square solid image, a halftone image of the 1-dot Keima pattern shown in Fig. 4 was created, where the "ghost" portion in Fig. 3 was evaluated for the appearance of a ghost attributed to the solid image. The ghost part appears. When the ghost appears, it appears in “ghost” in FIG. 3).

(Evaluation of black spot image)
The black spot evaluation uses the solid white image, confirms the number of black spots with a diameter (φ) of 0.3 mm or less in terms of one round of the electrophotographic photosensitive member, and evaluates according to the following criteria. Are shown in Tables 5 and 6. A has 0 black spots, B has 1 to 3 black spots, C has 3 to 4 black spots, and D has 5 or more black spots. In the present invention, A, B, and C were levels at which the effects of the present invention were obtained, and among them, A was judged to be an excellent level. On the other hand, D was judged to be a level where the present invention was not obtained.

(Evaluation of ghost images)
For ghost evaluation, in the ghost evaluation printing, the density difference between the halftone image density of the 1-dot Keima pattern and the image density of the ghost portion is measured by a spectral densitometer (trade name: X-Rite 504/508, X-Rite Co., Ltd.). Manufactured). Ten points were measured on one ghost evaluation print, the average of those 10 points was calculated as one result, and all the above five ghost evaluation prints were measured in the same manner. Their average value was determined. The difference in density between the halftone image density and the image density in the ghost portion is defined as the ghost image density difference. The smaller the ghost image density difference value, the better the ghost characteristics. Evaluation was performed according to the following criteria, and the results are shown in Tables 5 and 6. A is a ghost image density difference of less than 0.01, B is a ghost image density difference of 0.01 or more and less than 0.02, C is a ghost image density difference of 0.02 or more and less than 0.03, D is a ghost image density difference of. 03 or more and less than 0.04, E is a density difference with a ghost image density difference of 0.04 or more. In the present invention, A, B, and C were levels at which the effects of the present invention were obtained, and among them, A was judged to be an excellent level. On the other hand, D and E were determined to be levels at which the effects of the present invention were not obtained.

  From the results of Tables 5 and 6, the electrophotographic photosensitive member of the present invention gives good results for both the initial ghost, the ghost after 5000 sheets, and the initial black spot, improving the ghost and suppressing the black spot. Both can be achieved at a high level.

1 Electrophotographic photosensitive member 2 Axis 3 Charging means (primary charging means)
4 exposure light (image exposure light)
5 Developing means 6 Transfer means (transfer roller)
7 Cleaning means (cleaning blade)
8 Fixing means 9 Process cartridge 10 Guide means 11 Pre-exposure light P Transfer material (paper, etc.)
21 conductive support 22 first intermediate layer 23 second intermediate layer 24 charge generation layer 25 hole transport layer

Claims (10)

Electrons having a conductive support, a first intermediate layer formed on the conductive support, a second intermediate layer formed on the first intermediate layer, and a photosensitive layer formed on the second intermediate layer In photoconductors,
The first intermediate layer is
Metal oxide particles ,
At least one amine compound selected from the group consisting of a compound represented by the following formula (1), a compound represented by the following formula (2), and a polymer represented by the following formula (2);
Including
The content of the amine compound in the first intermediate layer is 1% by mass or more and 15% by mass or less with respect to the metal oxide particles in the first intermediate layer.
The electrophotographic photoreceptor, wherein the second intermediate layer contains metal oxide particles and does not contain the amine compound.

(In the formula (1), X ¹¹ , X ¹² and X ¹³ each independently represent a hydrogen atom, an alkyl group having 2 to 4 carbon atoms, or a hydroxyalkyl group having 2 to 4 carbon atoms, ¹¹ , at least one of X ¹² and X ¹³ is an alkyl group having 2 to 4 carbon atoms, or a hydroxyalkyl group having 2 to 4 carbon atoms, in formula (2), R ²¹ , R ²⁴ Each independently represents a hydrogen atom, a methyl group or an ethyl group, R ²² and R ²³ each independently represents a hydrogen atom or a methyl group, and the compound represented by the formula (2) has 2 or more carbon atoms. 4 or less.)   2. The electrophotographic photosensitive member according to claim 1, wherein the content of the amine compound is 3% by mass or more and 5% by mass or less with respect to the metal oxide particles in the first intermediate layer.   The electrophotographic photosensitive member according to claim 1, wherein the compound represented by the formula (1) is a secondary amine or a tertiary amine.   The electrophotographic photoreceptor according to claim 3, wherein the compound represented by the formula (1) is triethanolamine.   3. The electrophotographic photoreceptor according to claim 1, wherein the polymer of the compound represented by the formula (2) is polyethyleneimine.   6. The electrophotographic photosensitive member according to claim 1, wherein the metal oxide particles contained in the second intermediate layer have a volume average particle diameter of 1 nm or more and 9 nm or less. The metal oxide particles contained in the first intermediate layer and the metal oxide particles contained in the second intermediate layer are tin oxide, titanium oxide, or zinc oxide particles. The electrophotographic photosensitive member according to any one of 6. An electrophotographic photosensitive member according to any one of claims 1 to 7 , and at least one means selected from the group consisting of a charging means, a developing means, a transfer means, and a cleaning means, are integrally supported, and electrophotographic A process cartridge which is detachable from the apparatus main body. The electrophotographic photosensitive member according to any one of claims 1 to 7, a charging means, an exposure means, a developing means, and an electrophotographic apparatus characterized by having a transfer means. It is a manufacturing method of the electrophotographic photosensitive member as described in any one of Claim 1 to 7,
A coating solution for the first intermediate layer containing the metal oxide particles and the amine compound is applied onto the conductive support to form a coating film, and the coating film of the coating solution for the first intermediate layer is dried. A first step of forming the first intermediate layer;
The second intermediate layer coating liquid containing the metal oxide particles and not containing the amine compound is applied onto the first intermediate layer to form a coating film, and the second intermediate layer coating liquid is coated with the coating film . A method for producing an electrophotographic photoreceptor, comprising a second step of drying to form the second intermediate layer.

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