JP2003021985A - Electrophotographic photosensitive member, process cartridge having the electrophotographic photosensitive member, and electrophotographic apparatus - Google Patents

Abstract

(57) [Problem] To provide an electrophotographic photosensitive member which realizes stable direct charging for a long period of time by suppressing occurrence of charging unevenness, and a process cartridge and an electrophotographic apparatus having the electrophotographic photosensitive member. SOLUTION: A charging member is brought into contact with an electrophotographic photosensitive member to charge the electrophotographic photosensitive member, the charging member is made of an elastic material, and the surface of the charging member is in contact with the electrophotographic photosensitive member. An electrophotographic photosensitive member used for an electrophotographic device that moves with a speed difference and carries conductive particles on at least a contact surface between the charging member and the electrophotographic photosensitive member, wherein the electrophotographic photosensitive member has a cylindrical shape. At least a photosensitive layer and a protective layer are provided on a conductive support, and a drive transmission member and a bearing member are mounted in openings at both ends of the cylinder, and a runout accuracy when rotated about a central axis thereof is 120 μm or less. An electrophotographic photosensitive member, and a process cartridge and an electrophotographic apparatus having the electrophotographic photosensitive member.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic photosensitive member used in an image forming apparatus such as a copying machine, a process cartridge having the electrophotographic photosensitive member, and an electrophotographic apparatus.

[0002]

2. Description of the Related Art Conventionally, for example, in an image recording apparatus such as an electrophotographic apparatus or an electrostatic recording apparatus, an image carrier (charged body) such as an electrophotographic photosensitive member or an electrostatic recording dielectric has a required polarity.
A corona charger (corona discharger) has often been used as a charging device for uniformly charging (including static elimination) the electric potential.

The corona charger is a non-contact type charging device. For example, the corona charger is provided with a discharge electrode such as a wire electrode and a shield electrode surrounding the discharge electrode, and a discharge opening is made to face an image carrier, which is a member to be charged. In this case, the surface of the image bearing member is charged to a predetermined level by applying a high voltage to the discharge electrode and the shield electrode to add the discharge current (corona shower) to the surface of the image bearing member.

Recently, the ozone level is lower than that of corona chargers.
Due to advantages such as low power consumption, a contact type charging device (contact charging device) for charging a charged member by bringing a charging member applied with a voltage into contact with the charged member has been put into practical use as described above. ing.

The contact charging device contacts a charged member such as an image carrier with a conductive charging member such as a roller type (charging roller), a fur brush type, a magnetic brush type or a blade type,
A predetermined charging bias is applied to this charging member (contact charging member / contact charger, hereinafter referred to as contact charging member) to charge the surface of the body to be charged to a predetermined polarity and potential.

Charging mechanism of contact charging (charging mechanism,
In (charging principle), two types of charging mechanisms (1) discharge charging mechanism and (2) direct injection charging mechanism are mixed, and each characteristic appears depending on which one is dominant.

(1) Discharge Charging Mechanism This is a mechanism in which the surface of the charged body is charged by the discharge phenomenon occurring in the minute gap between the contact charging member and the charged body.

Since the discharge charging system has a constant discharge threshold between the contact charging member and the member to be charged, it is necessary to apply a voltage higher than the charging potential to the contact charging member. Further, compared with a corona charger, the generation amount is remarkably small, but generation of a discharge product is unavoidable in principle, so that a harmful effect due to active ions such as ozone is unavoidable.

For example, a roller charging method using a conductive roller (charging roller) as a contact charging member is preferable from the viewpoint of charging stability and is widely used. In this roller charging, the charging mechanism is a discharge charging mechanism. Is dominant.

That is, the charging roller is made of a conductive or medium-resistance rubber material or foam. Further, there is also one in which these are laminated to obtain desired characteristics. The charging roller has elasticity in order to obtain a constant contact with the member to be charged, and therefore has a large friction resistance, and in many cases, is driven by the member to be charged or driven with a slight speed difference.
Therefore, since the non-contact state cannot be avoided due to the uneven shape of the roller and the adhered matter of the body to be charged, in the conventional roller charging, the discharge charging mechanism is dominant in the charging mechanism.

More specifically, when the charging roller is pressed against the OPC photosensitive member having a thickness of 25 μm as the member to be charged to perform the charging process, about 640 V is applied to the charging roller. When the above voltage is applied, the surface potential of the photoconductor starts to rise, and thereafter, the surface potential of the photoconductor linearly increases with an inclination of 1 with respect to the applied voltage. Hereinafter, this threshold voltage is defined as the charging start voltage Vth.

That is, in order to obtain the photosensitive member surface potential Vd required for electrophotography, the charging roller requires a DC voltage higher than the required Vd + Vth. The system in which only the DC voltage is applied to the contact charging member in this way to charge the image carrier is called a "DC charging system".

However, in the DC charging method, the resistance of the contact charging member fluctuates due to environmental fluctuations, etc. Further, if the film thickness changes due to abrasion of the photoconductor as an image carrier, Vth fluctuates. It was difficult to set the potential to a desired value.

Therefore, as disclosed in Japanese Patent Laid-Open No. 63-149669, etc., in order to further uniformize the charging,
An “AC charging method” is used in which a vibration voltage in which an AC component having a peak-to-peak voltage of 2 × Vth or more is superimposed on a DC voltage corresponding to a desired Vd is applied to a contact charging member to charge the photoconductor. This is for the purpose of leveling the potential by AC, and the potential of the photoconductor converges on Vd which is the center of the peak of the AC voltage, and is not affected by disturbance such as environment.

However, even in such a contact charging device, since the essential charging mechanism uses the discharging phenomenon from the charging member to the photosensitive member, the voltage required for charging as described above. A value equal to or higher than the photoconductor surface potential + discharge threshold value is required, and a small amount of ozone is generated.

Further, when AC charging is performed for uniform charging, further ozone is generated, vibration noise (AC charging sound) between the contact charging member and the photoconductor due to the electric field of AC voltage, and discharge. Deterioration of the photoreceptor surface due to
It was a new problem.

(2) Direct injection charging mechanism This mechanism charges the surface of the photoconductor by directly injecting electric charges from the contact charging member to the body to be charged. Japanese Patent Laid-Open No. 06-0
It is proposed in Japanese Patent Publication No. 03921.

The medium-resistance contact charging member comes into contact with the surface of the photoconductor to directly inject the charge into the surface of the photoconductor without intervening the discharge phenomenon, that is, basically without using the discharge mechanism. Therefore, even if the voltage applied to the contact charging member is equal to or lower than the discharge threshold, the photoconductor can be charged to a potential corresponding to the applied voltage. This direct injection charging mechanism does not cause the generation of ions, so that no harm is caused by the generation of discharge.

More specifically, a voltage is applied to a contact charging member such as a charging roller, a charging brush or a charging magnetic brush to charge the charge holding member such as conductive particles in the trap order or the charge injection layer on the surface of the photoreceptor. Is a mechanism for directly injecting and charging. Since the discharge phenomenon is not dominant, the voltage required for charging is only the desired surface of the photoconductor and no ozone is generated.

(Powder coating on charging member) On the other hand, in order to prevent uneven charging of the contact charging device and to perform stable and uniform charging, a structure in which powder is applied to the contact surface of the charging member with the photoreceptor surface is disclosed in Japanese Patent Publication No. 07-99442. However, although the charging member is driven to rotate and the generation of ozone products is significantly less than that of a corona charger such as a scorotron, the charging principle is the same as in "(1) Discharge" above. As described in "Charging mechanism", corona charging due to electric discharge is still predominant. Especially, in order to obtain more stable charging uniformity, D
Since the voltage in which AC is superimposed on C is applied, the ozone products due to the discharge increase. Therefore, when a device is used for a long period of time or a device without a cleaning member is used for a long period of time, harmful effects such as image deletion due to ozone products are likely to appear.

In order to solve these problems, a charging device for charging a charging member to which a voltage has been applied by contacting a member to be charged, that is, a photosensitive member, the charging member being composed of an elastic body, A structure in which the surface of the charging member has a speed difference with respect to the surface of the photosensitive member and at least the conductive particles are carried on the contact surface between the charging member and the photosensitive member is disclosed in Japanese Patent Laid-Open No.
It is proposed in Japanese Patent Laid-Open No. 307454. As a result, sufficient contact property can be obtained in direct charging, and uniform charging is possible.

However, in the case of such a charging method,
If the accuracy of the photoreceptor is not maintained to some extent, image defects due to uneven charging may occur.

To explain this in detail, the charging in the present invention is a method of directly injecting the charge into the photosensitive member from the contact portion between the charging member and the photosensitive member, unlike the method of charging the surface of the photosensitive member by discharging. Therefore, if the photoconductor is eccentric during rotation, the pressure and the nip width on the contact surface with the charging member change with the rotation cycle of the photoconductor, and the distribution density of the conductive particles existing on the contact surface and injecting charges Unevenness occurs, resulting in uneven charging.

Here, the runout accuracy of the photoconductor becomes more remarkable as the outer diameter of the photoconductor becomes smaller and as the axial length becomes longer. Therefore, assuming a photoconductor having a diameter of φ100 mm or more and a length of 200 mm or less, for example, the contact width (nip width) in the traveling direction can be stably widened, and charging due to the deflection accuracy of the photoconductor can be performed. Mura is unlikely to occur. However, in the small-diameter, long-axis type photoconductors currently used in many image forming apparatuses such as LBPs and copiers, if the deflection accuracy is not regulated to some extent, it exists in the contact surface and conducts electric charges. Since the distribution density of the particles changes greatly, a problem of uneven density due to uneven charging occurs. For example, a photosensitive member having a diameter of φ24, 30, 40, 60 and a length of 200 mm or more corresponding to a transfer sheet having a length of A4 size or more is targeted.

Further, regarding the charging member, when a roller-shaped elastic member is used, generally, the larger the outer diameter of the roller, the wider the contact width (nip width) with respect to the photosensitive member can be made. However, in order to reduce the size of the apparatus and the like, a diameter of 30 mm or less or 20 mm or less is actually used, so that it is necessary to increase the accuracy of the photoconductor to cope with the problem.

[0026]

Therefore, an object of the present invention is to charge the electrophotographic photosensitive member by bringing the charging member into contact with the electrophotographic photosensitive member, and the charging member is composed of an elastic body,
Further, it is used in an electrophotographic apparatus in which the surface of the charging member moves with a speed difference with respect to the electrophotographic photosensitive member, and which carries conductive particles at least on the contact surface between the charging member and the electrophotographic photosensitive member. To provide an electrophotographic photosensitive member which suppresses uneven charging in the electrophotographic photosensitive member and realizes stable direct charging for a long period of time, and a process cartridge and an electrophotographic apparatus having the electrophotographic photosensitive member.

[0027]

According to the present invention, a charging member is brought into contact with an electrophotographic photosensitive member to charge the electrophotographic photosensitive member, the charging member is made of an elastic body, and the surface of the charging member is formed. In an electrophotographic photosensitive member used in an electrophotographic apparatus that moves with a speed difference with respect to the electrophotographic photosensitive member, and carries conductive particles at least on the contact surface between the charging member and the electrophotographic photosensitive member, When the electrophotographic photosensitive member has at least a photosensitive layer and a protective layer on a cylindrical conductive support, a drive transmission member and a bearing member are attached to the openings at both ends of the cylinder, and the electrophotographic photosensitive member is rotated about its central axis. Runout accuracy is 120 μm
The following are an electrophotographic photoreceptor, a process cartridge and an electrophotographic apparatus having the electrophotographic photoreceptor.

In the present invention, the above-described structure eliminates image defects due to uneven charging.

[0029]

BEST MODE FOR CARRYING OUT THE INVENTION First, a charging method in the present invention will be described.

The charging device of the present invention (FIG. 1) comprises a conductive elastic roller 2 (hereinafter referred to as a charging roller) and conductive particles 3 (hereinafter referred to as a charging promotion particle) for the purpose of promoting charging. It is composed of a regulating member 4 which is a coating means. The charging target 2 is charged in a state where the charging promoting particles 3 are applied to the contact nip n between the charging roller 2 and the charging target 1. As a result, the charging roller 2 can come into contact with the member to be charged 1 with a speed difference, and at the same time, the charge can be directly injected into the member to be charged 1 densely via the charging accelerating particles 3. Therefore, in the present invention, a high charging efficiency, which has not been obtained by the conventional roller charging, can be obtained, and a potential substantially equal to the potential applied to the charging member can be applied to the member to be charged. Therefore, the bias required for charging is sufficient as the voltage corresponding to the potential required for the member to be charged, and a stable and safe charging method that does not use the discharge phenomenon is realized. S1 is a charging bias application power source for the charging roller 2.

Next, the main constituent members of the charger will be described.

[Charging Roller] The charging roller 2 is formed by forming a medium resistance layer 2b of rubber or foam on the cored bar 2a. The medium resistance layer 2b is formulated with a resin (for example, urethane), conductive particles (for example, carbon black), a sulfiding agent, a foaming agent, etc., and is formed in a roller shape on the cored bar 2a. Then, if necessary, polish the surface to a diameter of 2
An elastic conductive roller 2 having a length of 0 mm and a longitudinal length of 310 mm was prepared. When the roller resistance of this example was measured, it was 100 k.
It was Ω. Total pressure 9.8N (1kg) on the core of the roller 2.
100 V to the core metal 2a and the aluminum drum in a state of being crimped to the φ30 aluminum drum so that the load of
Was applied and measured. Here, it is important that the elastic roller 2 functions as an electrode. That is, it is necessary to have elasticity and obtain a sufficient contact state, and at the same time, have a sufficiently low resistance to charge the moving charged body. On the other hand, it is necessary to prevent voltage leakage when there is a defective portion such as a pinhole on the charged body. When an electrophotographic photosensitive member is used as the member to be charged, a resistance of 10 ⁴ to 10 ⁷ Ω is desirable in order to obtain sufficient chargeability and leak resistance.

If the hardness of the charging roller is too low, the shape of the charging roller will not be stable, resulting in poor contact. If it is too high, the charging nip cannot be secured, and the microscopic contact with the surface of the photoconductor will be poor. The Asker C hardness is preferably in the range of 25 to 50 degrees.

The material of the charging roller is not limited to the elastic foam, but the material of the elastic body is EPD.
Examples of the rubber material include M, urethane, NBR, silicone rubber, IR, and the like, in which a conductive material such as carbon black or a metal oxide is dispersed for resistance adjustment, or a material obtained by foaming these. It is also possible to adjust the resistance by using an ion conductive material without particularly dispersing the conductive substance.

The charging member is not limited to the charging roller, and an elastic body such as a fur brush in which each pile has elasticity can be used. Here, the fur brush roller has a resistance-adjusted fiber (trade name Rec: Unitika Co., Ltd.) planted at a density of 155 fibers / mm ² and a fiber length of 3 mm.
It is formed on a pile with, and then the pile is wound and fixed on a core metal having a diameter of 6 mm and formed into a roller shape.

[Charge Accelerating Particles] In this example, conductive zinc oxide particles 3 having a specific resistance of 10 ⁶ Ω · cm and an average particle size of 3 μm were used. As the material for the particles, various conductive particles such as conductive inorganic particles such as other metal oxides or a mixture with organic substances can be used. Here, the particle resistance is preferably 10 ¹⁰ Ω · cm or less in order to transfer charges through the particles. Here, the resistance was measured by the tablet method and normalized. Approximately 0.5 g of powder sample was placed in a cylinder with a bottom area of 2.26 cm ² and 147 N (15 k
Simultaneously with the pressurization of g), a voltage of 100 V was applied to measure the resistance value, and then normalized to calculate the specific resistance. Also,
The particle size is preferably 50 μm or less in order to obtain good charging uniformity. The lower limit of the particle size is 10 nm as a limit for stably obtaining the particles. In the present invention, the particle size when the particles are formed as an aggregate is defined as the average particle size of the aggregate. To measure the particle size, 100 or more particles were extracted from observation by an optical or electron microscope, the volume particle size distribution was calculated with the maximum chord length in the horizontal direction, and the 50% average particle size was determined.

[Charge promoting particles coating means] Charge promoting particles 3
In order to uniformly supply the toner to the contact nip between the charging roller and the photoconductor, charging-promoting particle coating means is provided.

In the first embodiment, the regulating blade 4 is brought into contact with the photoconductor 1 to hold the charge promoting particles 3 between the photoconductor 1 and the regulating blade 4. Then, as the photoconductor 1 rotates, a certain amount of the charge promoting particles 3 is applied to the charging roller 2. As a simpler configuration, there is a method in which a foam or a fur brush containing the electrification accelerating particles 3 is brought into contact with an object to be charged, but the present invention is not limited to this configuration.

In the second embodiment, the regulating blade 4 is brought into contact with the charging roller 2 so that the charging roller 2 and the regulating blade 4 are brought into contact with each other.
A structure for holding the charge accelerating particles 3 in between is adopted. Then, as the charging roller 2 rotates, a certain amount of the charge promoting particles 3 is applied to the photoconductor 1.

In the present invention, the charging member is rotated with a speed difference with respect to the member to be charged. Therefore, the vicinity of the contact nip of the charging member composed of an elastic body is largely deformed as compared with the case of being driven, and the particles adhering to the surface of the charging member easily migrate to the charged body, and the device is used. As a result, the particles on the surface of the charging member decrease. Therefore, the configuration is such that a fixed amount of charge promoting particles is always supplied.

[Operation of Charging Device] The operation of the charging device of the present invention will be described with reference to the first embodiment. The charged body is assumed to be an electrophotographic photoreceptor. The member to be charged 1 has a drum shape and rotates at a constant peripheral speed. The charger of the present invention was used as a charger for uniformly charging this surface.

First, the charge promoting particles 3 are applied to the surface of the photoconductor by the regulating blade 4. After that, it reaches the charging roller unit. The charging roller 2 was driven so that the roller surface moved in the opposite direction to the photoconductor at a constant speed, and a DC voltage was applied to the roller core metal 2a. As a result, the surface of the photoconductor is charged to a potential equal to the applied voltage. The electrification is performed directly by the electrification promoting particles 3 existing in the contact nip between the roller and the electrified body rubbing the surface of the electrified body without a gap.

Next, an overall schematic structure is shown in FIG.

In FIG. 2, reference numeral 1 denotes a rotary drum type electrophotographic photosensitive member as an image bearing member, which is rotationally driven in a clockwise direction indicated by an arrow at a predetermined peripheral speed (process speed PS).

A charging roller 2 serves as a contact charging member for the photosensitive member 1. In this example, the contact charging device of the second embodiment described above is used, and the charging accelerating particle supply means 4 is disposed on the charging roller 2 side. The charging roller 2 is rotationally driven in the clockwise direction indicated by the arrow with a peripheral speed difference so that the surface of the charging roller and the surface of the photosensitive member move in opposite directions in the charging nip portion n. The core metal 2a of the charging roller 2 is applied with a DC voltage of -700 V from the charging bias applying power source S1.

Therefore, as described above, the surface of the rotating photoconductor 1 is applied by the charging accelerating particle supply means 4 to the charging roller 2 so that the charging roller 2 comes into contact with the photoconductor at a peripheral speed difference. Since the charging accelerating particles 3 are present in the charging nip portion n, the charging of the photoconductor 1 by the charging roller 2 is dominated by the direct injection charging, and the charging bias voltage applied to the charging roller 2 becomes almost the same potential. It is charged.

Reference numeral 5 is a laser beam scanner (exposure device) including a laser diode, a polygon mirror and the like. This laser beam scanner outputs a laser beam whose intensity is modulated corresponding to a time-series electric digital pixel signal of target image information, and scans and exposes L the uniformly charged surface of the rotating photoconductor 1 with the laser beam. By this scanning exposure L, an electrostatic latent image corresponding to the target image information is formed on the surface of the rotating photoconductor 1.

Reference numeral 6 is a developing device. The electrostatic latent image on the surface of the rotating photoconductor 1 is developed as a toner image by this developing device. The developing device 6 is, for example, a one-component or two-component non-contact reversal developing device having a non-magnetic developing sleeve 6b containing a magnet roller 6a as a developer carrying and conveying member. Reference numeral a denotes a developing area portion which is an opposing portion of the photoconductor 1 and the developing sleeve 6b. S2 is a developing sleeve 6b
Is a developing bias application power source.

Reference numeral 7 denotes a transfer roller as a transfer means,
The transfer nip portion b is formed by pressing the photosensitive member 1 with a predetermined pressure. A transfer material P as a recording medium is fed to the transfer nip portion b from a paper feeding portion (not shown) at a predetermined timing.
Further, by applying a predetermined transfer bias from the power source S3 to the transfer roller 7, the toner image on the side of the photoconductor 1 is sequentially transferred onto the surface of the transfer material P fed to the transfer nip portion b.

Reference numeral 8 is a fixing device. The transfer material P that has been fed to the transfer nip portion b and has received the transfer of the toner image on the photoconductor 1 side.
Is separated from the surface of the rotating photoconductor 1 and is introduced into the fixing device 8, where the toner image is fixed to form an image-formed product (print, copy).

Reference numeral 9 denotes a process cartridge which can be attached to and detached from the printer body. In the printer of this example, three process devices including a photoconductor 1, a charging roller 2 including a charging-promoting particle supply unit 4, and a developing device 6 are collectively configured as a process cartridge that can be attached to and detached from a printer body. The combination of process equipment to be made into a process cartridge is not limited to the above, and is arbitrary. 1
Reference numeral 0 is a mounting / demounting guide / holding member for the process cartridge.

The charge-promoting particles 3 are preferably colorless or nearly white particles so as not to hinder the exposure of the latent image particularly when used for charging the photoreceptor 1. Further, in the case of performing color recording, it is desirable that the color is colorless or close to white in consideration of the case where the charging accelerating particles 3 are transferred from the photosensitive member to the recording material P. Further, in order to prevent light scattering by the charge promoting particles at the time of image exposure, it is desirable that the particles have a size smaller than the constituent pixel size.

Next, the electrophotographic photosensitive member of the present invention will be described. The support may be any one as long as it has a cylindrical shape having conductivity, and examples thereof include metals such as aluminum, aluminum alloys, copper, zinc, stainless steel, vanadium, molybdenum, chromium, titanium, nickel and indium. Molded into a drum shape, metal foil such as aluminum or copper laminated on a plastic film, aluminum, indium oxide, tin oxide, etc. deposited on a plastic film, conductive material alone or coated with a binder resin Examples of the metal include a metal, a plastic film, and paper on which a conductive layer is provided.

The structure of the photosensitive layer is roughly classified into a single layer type containing both a charge generating substance and a charge transporting substance in the same layer, and a laminated type having a charge generating layer and a charge transporting layer.

When the photosensitive layer is a laminated type, as the charge generating substance, inorganic charge generating substances such as selenium, selenium-tellurium and amorphous silicon; pyrylium type dyes, thiapyrylium type dyes, azurenium type dyes, thiacyanine type dyes and quinocyanine are used. Cationic dyes such as system dyes; Squarium salt pigments; Phthalocyanine pigments; Polycyclic quinone pigments such as anthanthrone pigments, dibenzpyrenequinone pigments and pyrantrone pigments; Indigo pigments; Quinacridone pigments; and Azo pigments Examples include pigments and the like. The charge generation layer can be formed as a vapor deposition layer of these charge generation substances by a vacuum vapor deposition apparatus, or can be formed as a coating layer by applying a coating liquid dispersed or dissolved in a binder resin and drying. .

The binder resin can be selected from a wide range of insulating resins, and can also be selected from organic photoconductive polymers such as poly-N-vinylcarbazole and polyvinylpyrene. Desirably, polyvinyl butyral, polyarylate (polycondensate of bisphenol A and phthalic acid, etc.), polycarbonate, polyester, polyvinyl acetate, acrylic resin, polyacrylamide, polyamide, cellulose resin, urethane resin, epoxy resin, polyvinyl alcohol, etc. Resins of

The binder resin contained in the charge generation layer is preferably 80% by weight or less, more preferably 50% by weight or less, based on the total weight of the charge generation layer.

The thickness of the charge generation layer is preferably 5 μm or less, and particularly preferably 0.01 to 1 μm.

The charge transport layer comprises a polycyclic aromatic compound having a structure such as biphenylene, anthracene, pyrene and phenanthrene in the main chain or side chain; a nitrogen-containing ring compound such as indole, carbazole, oxadiazole and pyrazoline; hydrazone compound And a charge transport substance such as a styryl compound are dissolved in a binder resin to form a coating liquid, and the coating liquid is dried.

As the binder resin, polyarylate, polysulfone, polyamide, acrylic resin, acrylonitrile resin, methacrylic resin, vinyl chloride resin, vinyl acetate resin, phenol resin, epoxy resin, polyester resin, alkyd resin, polycarbonate resin, polyurethane, Alternatively, copolymers thereof such as styrene-butadiene copolymer, styrene-acrylonitrile copolymer and styrene-maleic acid copolymer may be mentioned. In addition to such an insulating polymer, an organic photoconductive polymer such as polyvinylcarbazole, polyvinylanthracene or polyvinylpyrene can also be used.

The ratio of the binder resin to the charge transport substance is preferably 10 to 500 parts by weight of the charge transport substance per 100 parts by weight of the binder resin.

The thickness of the charge transport layer is 5 to 40 μm.
Is preferable, and particularly preferably 10 to 30 μm.

When the photosensitive layer is of a single layer type, the photosensitive layer is prepared by applying a solution prepared by dispersing and dissolving the above-mentioned charge generating substance and charge transporting substance in the above-mentioned binder resin onto a support and drying. Can be formed.

In the present invention, an undercoat layer having a barrier function and an adhesive function may be provided between the support and the photosensitive layer.

Examples of the material for the undercoat layer include polyvinyl alcohol, polyethylene oxide, nitrocellulose, ethyl cellulose, methyl cellulose, ethylene-acrylic acid copolymer, alcohol-soluble amide, polyamide, polyurethane, casein, glue and gelatin. The undercoat layer can be formed by applying a solution prepared by dissolving these materials in a suitable solvent onto a support and drying. The film thickness is preferably 5 μm or less, and particularly preferably 0.2 μm to 3 μm.

When the exposure is a laser beam, it is preferable to provide a conductive layer between the undercoat layer and the support in order to prevent interference fringes. The conductive layer can be formed by applying a solution in which a conductive powder such as carbon black and metal particles is dispersed in a binder resin on a support and drying the solution. The thickness of the conductive layer is preferably 5 to 40 μm, and particularly preferably 5 to 30 μm.

The various layers described above are formed by a coating method such as a dip coating method, a spray coating method, a beam coating method, a spinner coating method, a roller coating method, a Meyer bar coating method and a blade coating method using an appropriate organic solvent. can do.

Next, the protective layer of the electrophotographic photosensitive member of the present invention will be described. In the present invention, it is preferable to use a curable resin as the binder resin for the protective layer from the viewpoint of enhancing the surface hardness of the protective layer and the abrasion resistance against a developer and the like. In addition, curable resins have been widely used as a binder resin for a protective layer because the environmental resistance variation of the protective layer is small and the fine particles have excellent dispersibility and stability after dispersion. There is something. The acrylic resin, the phenol resin, the epoxy resin, the urethane resin, and the siloxane resin used as the binder resin of the surface protective layer in the present invention have high mechanical strength, so that scratches due to durability and shortening of life due to abrasion are shortened. It has the feature of being able to suppress such problems. Among them, the phenol resin is excellent in that it can provide an electrophotographic photosensitive member and an electrophotographic apparatus having excellent resistance to use environment because the resistance variation of the surface protective layer under high temperature and high humidity and room temperature and low humidity is small.

In the present invention, conductive particles may be dispersed in order to enhance the electric conductivity in the protective layer. Examples of the conductive particles include metals, metal oxides and carbon black. As the metal, aluminum, zinc,
Examples thereof include copper, chromium, nickel, silver and stainless steel, or those obtained by vapor-depositing these metals on the surface of plastic particles. Examples of the metal oxide include zinc oxide, titanium oxide, tin oxide, antimony oxide, indium oxide, bismuth oxide, indium oxide doped with tin, zirconium oxide doped with antimony and tantalum, and the like. These may be used alone or in combination of two or more. When two or more kinds are used in combination, they may be simply mixed, or may be in the form of solid solution or fusion.

The average particle size of the conductive particles used in the present invention is preferably 0.3 μm or less, and particularly preferably 0.1 μm or less, from the viewpoint of the transparency of the protective layer.

Further, in the present invention, it is particularly preferable to use a metal oxide among the above-mentioned conductive particles in terms of transparency.

Examples of the fluorine atom-containing compound in the present invention include a fluorine-containing silane coupling agent, a fluorine-modified silicone oil and a fluorine-based surfactant.
Although preferable compound examples are shown in Tables 1 to 3, the present invention is not limited to these compounds. The method of adding the fluorine atom-containing compound includes a method of simply adding it at the time of dispersion and a method of surface-treating the conductive particles, but the present invention is not limited to these addition methods. By containing these fluorine atom-containing compounds, it becomes possible to disperse even in an alcohol solvent, and it becomes possible to apply the compound on a photoreceptor by a dip coating method.

The fluorine atom-containing resin particles used in the present invention include tetrafluoroethylene, trifluoroethylene chloride resin, hexafluoroethylene propylene resin, vinyl fluoride resin, vinylidene fluoride resin, and difluorodichloride. It is preferable to appropriately select one kind or two or more kinds from the ethylene resin and the copolymer thereof, and the tetrafluoroethylene resin and the vinylidene fluoride resin are particularly preferable. The molecular weight of the resin particles and the particle size of the particles can be appropriately selected and are not particularly limited.

The fluorine atom-containing compound is added when the conductive particles are dispersed, or the surface of the conductive particles is surface-treated with the fluorine atom-containing compound to make the fluorine atom-containing resin particles conductive. It also has a role to prevent mutual particles from coagulating together with the functional particles.

By adding a fluorine atom-containing compound or subjecting the conductive particles to a surface treatment, the dispersibility of the conductive particles and the fluorine atom-containing resin particles in the resin solution and Dispersion stability has been dramatically improved. In addition, by forming a secondary particle of dispersed particles by dispersing fluorine atom-containing resin particles in a liquid in which a fluorine atom-containing compound is added and conductive particles are dispersed, or in which a surface-treated conductive particle is dispersed. In addition, a coating liquid that is very stable and has good dispersibility over time can be obtained.

As a method of surface-treating the conductive particles, the conductive particles and the surface-treating agent are mixed and dispersed in a suitable solvent,
A surface treatment agent is attached to the surface of the conductive particles. As a dispersing method, a usual dispersing means such as a ball mill or a sand mill can be used. Next, the solvent may be removed from this dispersion solution and fixed on the surface of the conductive particles. Further, if necessary, a heat treatment may be further performed thereafter. Further, a catalyst for accelerating the reaction can be added to the treatment liquid. Furthermore, if necessary, the surface-treated conductive particles can be further pulverized.

The ratio of the fluorine atom-containing compound to the conductive particles is influenced by the particle size of the particles, but is preferably 1 to 65% by weight based on the weight of the surface-treated conductive particles. Is preferably 1 to 50% by weight.

As described above, the dispersion of the fluorine atom-containing resin particles can be achieved by dispersing the conductive particles after adding the fluorine atom-containing compound or using the conductive particles surface-treated with the fluorine atom-containing compound. It is possible to form a protective layer that is stable and has excellent slipperiness and releasability.
However, recently, colorization, high image quality, and high stability have advanced, and more environmental stability has been demanded.
The protection layer has come to require even more environmental stability.

Further, in the present invention, in order to form a protective layer having more environmental stability, a siloxane compound represented by the following general formula (1) is added at the time of dispersing conductive particles,
Alternatively, by mixing the conductive particles that have been surface-treated in advance, it was possible to obtain a protective layer that was more excellent in environmental stability.

[0080]

[Chemical 2] In the formula, A is a hydrogen atom or a methyl group, and the proportion of hydrogen atoms in all A is in the range of 0.1 to 50%,
n is an integer of 0 or more.

By adding this siloxane compound and then dispersing it in a coating liquid, or by dispersing the surface-treated conductive metal oxide fine particles in a binder resin dissolved in a solvent, the secondary particles of the dispersed particles can be obtained. A coating liquid that was stable and stable over time without formation was obtained. Furthermore, a protective layer formed from this coating liquid was highly transparent, and a film having particularly excellent environmental resistance was obtained.

The molecular weight of the siloxane compound represented by the general formula (1) is not particularly limited, but when the surface treatment is performed, it is better that the viscosity is not too high because of its easiness, and the weight average molecular weight is A few hundred to tens of thousands is suitable.

[0083]

[Table 1]

[0084]

[Table 2]

[0085]

[Table 3]

There are two types of surface treatment methods, wet type and dry type. In the wet method, the conductive metal oxide particles are dispersed in a solvent with a siloxane compound represented by the general formula (1), and the siloxane compound is attached to the surface of the fine particles. As a dispersing means, a general dispersing means such as a ball mill or a sand mill can be used. Next, this dispersion solution is fixed to the surface of the conductive metal oxide fine particles. In this heat treatment, Si-H bond in siloxane is oxidized by hydrogen in the air in the heat treatment process to oxidize hydrogen atom, and a new siloxane bond is formed. As a result, siloxane develops into a three-dimensional structure, and the surface of the conductive metal oxide fine particles is covered with this network structure. Thus, the surface treatment is completed by fixing the siloxane compound to the surface of the conductive metal oxide fine particles, but the fine particles after the treatment may be subjected to a pulverization treatment, if necessary. In the dry treatment, the siloxane compound is attached to the surface of the fine particles by mixing the siloxane compound and the conductive metal oxide fine particles without using a solvent and kneading. After that, the surface treatment is completed by performing heat treatment and crushing treatment as in the wet treatment. The ratio of the siloxane compound to the conductive metal oxide fine particles in the present invention depends on the particle size of the fine particles, the ratio of methyl groups to hydrogen atoms in siloxane, and the like, but is 1 to 50.
It is preferably in the range of% by weight, particularly preferably in the range of 3 to 40% by weight.

The ratio of the resin to the conductive particles is a value that directly determines the resistance of the protective layer, and the volume resistivity of the protective layer is 1
It is set to fall within the range of 0 ¹⁰ to 10 ¹⁵ (Ω · cm), but 10 ¹² under normal temperature (23 ° C.) and normal humidity (50%) conditions.
It is more preferably 10 ¹⁴ or less. Since the film strength becomes weaker as the amount of the conductive particles increases, it is preferable to reduce the amount of the conductive particles within a range in which the resistance and the residual potential of the protective layer are allowable. From these, the weight P / B ratio of the conductive particles (P) and the resin (B) is
The range of 5/1 to 5/5 is preferable, and 5 / 1.5 to 5
The range of / 4 is more preferable.

In the present invention, additives such as coupling agents and antioxidants may be added to the protective layer for the purpose of improving dispersibility, binding property and weather resistance.

Next, the shake accuracy of the photosensitive member can be obtained by using the axis line in the longitudinal direction of the photosensitive member as a reference line and defining the maximum value of the shake width (μm) of the outer peripheral surface of the photosensitive member with respect to the reference line. This maximum value is affected by the accuracy of each of the support, the photosensitive layer, the driving member, and the bearing member, and also by the outer diameter of the photosensitive member and the length of the shaft. As described above, a photosensitive layer and a protective layer are respectively applied, and a driving member and / or a bearing member is attached to both ends of the photosensitive layer and the protective layer, and the swing width when rotated about the central axis is 120 μm or less, more preferably 80 μm.
A prescribed effect can be obtained by defining the following. As a method for measuring the shake accuracy of the photoconductor, a non-contact measuring method using a low-power visible infrared laser was used.
Specifically, when the photosensitive member is fixed to the measuring table by the central axis of the driving member and / or the bearing member attached to the photosensitive member, and the laser beam is irradiated from above at three points of the upper end, the center, and the lower end in the longitudinal direction. The size of the shadow produced by the photoconductor is measured, and the deviation of the outer diameter of the photoconductor with respect to the central axis is calculated from the measured size. Further, by measuring a total of 8 points while rotating the photoconductor in the circumferential direction, it is possible to obtain the shake accuracy of the photoconductor in the present invention. As a method for improving the deflection accuracy of the photoconductor, it is preferable to perform cutting on the aluminum support. Specifically, a cutting blade is pressed against the outer peripheral surface of the cylindrical body to uniformly cut the surface while rotating the cylindrical body to increase the straightness of the outer peripheral surface, or a method for driving the inner peripheral surface of the cylindrical body. There is a so-called spigot processing method in which a cutting edge is pressed against a portion where the member and / or the bearing member come into contact with each other to perform cutting so as to enhance the contact accuracy between the photoconductor and the driving member and / or the bearing member.

[0090]

EXAMPLES Example 1 An aluminum cylinder having a diameter of 30φ and 357.5 mm was prepared by hot extrusion of aluminum, and the outer peripheral surface and the inner peripheral surface were cut. For cutting, press the cutting edge against one end of the aluminum cylinder, fix the cutting tool to the lathe, and cut the cutting edge of the cutting tool while rotating the cylinder at a feed rate of 50 μm per rotation of the cylinder. processed. Furthermore, 3 from the openings at both ends of the cylinder
The cutting process was similarly performed on the 0 mm inner peripheral surface.

The aluminum cylinder obtained as described above is used as a support, and a coating material composed of the following materials is applied to the support by a dip coating method, and the temperature is set to 140 ° C.
By heat-curing for 30 minutes, a conductive layer having a film thickness of 15 μm was formed.

[0092]     Conductive pigment: Titanium oxide coated with tin oxide ... 10 parts                                               (Parts by weight, the same below)     Resistance adjusting pigment: Titanium oxide ... 10 parts     Binder resin: Phenolic resin ... 10 parts     Leveling agent: Silicone oil ... 0.001 part     Solvent: / methanol / methyl cellosolve = 1/1 ... 20 parts

On top of this, N-methoxymethylated nylon 3
Part and 3 parts of copolymerized nylon were dissolved in 65 parts of methanol and 30 parts of n-butanol by a dip coating method to form an intermediate layer having a film thickness of 0.5 μm.

Next, the Bragg angle 2θ ± 0.2 ° in CuKα characteristic X-ray diffraction is 9.0 °, 14.2 °, 23.
4 parts of oxytitanium phthalocyanine having strong peaks at 9 ° and 27.1 °, butyral resin (trade name BX
-1: Sekisui Chemical Co., Ltd. 2 parts and cyclohexanone 80 parts were dispersed for 4 hours by a sand mill using φ1 mm glass beads, and then 115 parts of methyl ethyl ketone was added to obtain a charge generation layer dispersion liquid. This was applied onto the intermediate layer by a dip coating method to form a charge generation layer having a thickness of 0.2 μm.

Next, the following structural formula

[0096]

[Chemical 3] 10 parts of styryl compound and polycarbonate resin (trade name Iupilon Z-200: manufactured by Mitsubishi Gas Chemical Co., Inc.) 1
20 parts of dichloromethane and 6 parts of monochlorobenzene
A charge transport layer having a thickness of 20 μm was formed by dissolving in 0 part of a mixed solvent, applying this solution on the above charge generation layer by a dip coating method, and drying at 115 ° C. for 60 minutes.

Next, as a protective layer, 20 parts of antimony-doped tin oxide fine particles surface-treated with a compound of the following structural formula (treatment amount 7%),

[0098]

[Chemical 4] Antimony-doped tin oxide fine particles 30 surface-treated (25%) with the methyl hydrogen silicone oil described in [Chemical Formula 1] (trade name KF-99: manufactured by Shin-Etsu Silicone Co., Ltd.)
Part, [Chemical Formula 5] UV curable acrylic resin (trade name: Biscoat # 295: manufactured by Osaka Organic Chemical Industry Co., Ltd.) 18
Department,

[0099]

[Chemical 5] As a polymerization initiator, 1 part of 2-methylthioxanthone and 150 parts of ethanol were dispersed in a sand mill for 66 hours. Further, 20 parts of polytetrafluoroethylene fine particles (average particle size 0.18 μm) are added and dispersed,
This was used as a preparation liquid.

After that, a film was formed by a dip coating method, and a film was formed with a high pressure mercury lamp at a light intensity of 320 mW / cm ²
Curing was carried out for 0 seconds, and then it was dried with hot air at 120 ° C. for 2 hours to form a protective layer having a film thickness of 4 μm, thereby preparing an electrophotographic photoreceptor. Further, the protective layer preparation liquid had good dispersibility, and the film surface was a uniform and even surface.

The electrophotographic photosensitive member produced as described above is coated with an adhesive on the contact surfaces of the driving member and the bearing member in the openings at both ends thereof, and is attached to the photosensitive member. When the accuracy is measured, the measured value of runout accuracy is 50μ.
It was m.

For the evaluation of the test, LBP manufactured by Canon Inc. was used.
An actual machine obtained by modifying the 930 into the configuration shown in FIG. 2 was used.

As described above, the charging roller 2 used is an elastic conductive roller having a diameter of 12 mm and a longitudinal length of 310 mm, and the process speed of the photosensitive member is 100 mm / min.
The charging roller is 150 mm / mi in the opposite direction to the photoconductor.
It was rotated at a process speed of n.

A charging bias applying power source S1 is applied to the charging roller.
Then, a DC voltage of −700 V was applied.

As an evaluation, 23 ° C./50%, 15 ° C./1
0%, initial in each environment of 30 ℃ / 80%, and A
Images of three types of halftone, solid black, and solid white after running for 4,5,000 sheets were viewed. Image defects (uneven density) due to uneven charging were evaluated on a 5-point scale. The results are shown in Table 4.

Example 2 A plurality of photoconductors were prepared in the same manner as in Example 1 except that the inner peripheral surface of the aluminum cylinder was not cut in Example 1. The runout accuracy of the photoconductor after completion is measured, and the runout accuracy is 80 μm.
The sample was taken out and evaluated in the same manner as in Example 1. The results are shown in Table 4.

[Embodiment 3] A plurality of photoconductors were prepared in the same manner as in Embodiment 1 except that the inner peripheral surface of the aluminum cylinder was not cut. Measure the runout accuracy of the photoconductor after completion, and the runout accuracy is 100μ.
The sample of m was taken out and evaluated in the same manner as in Example 1. The results are shown in Table 4.

[Example 4] A photoconductor was prepared in the same manner as in Example 1 except that the inner peripheral surface and the outer peripheral surface of the aluminum cylinder were not cut.
Measure the runout accuracy of the photoconductor after completion, and the runout accuracy is 120
Those having a thickness of μm were extracted and evaluated in the same manner as in Example 1. The results are shown in Table 4.

[Comparative Examples 1 and 2] Photoreceptors were prepared in the same manner as in Example 2 above, and the deflection accuracy of the completed photoreceptors was measured. Samples with deflection accuracy of 150 μm and 180 μm were taken out. Evaluation was carried out in the same manner as in Example 1.
The results are shown in Table 4.

Example 5 In the above Example 1, the ultraviolet curable acrylic resin was changed to a novolac type phenol resin (trade name CMK-2400: Showa Highpolymer Co., Ltd.), and a polymerization initiator was not added. Then, 1 part of hexamethylenetetramine was added as a curing agent to prepare a preparation liquid.

Using this dispersion, a film was formed on the charge transport layer by a dip coating method, and dried with hot air at 145 ° C. for 1 hour to form a protective layer having a thickness of 4 μm. An electrophotographic photoreceptor was prepared in the same manner. Further, the protective layer preparation liquid had good dispersibility, and the film surface was a uniform and even surface.

The shake accuracy of the photosensitive member after completion was measured and found to be 50 μm. Using this, evaluation was performed in the same manner as in Example 1. The results are shown in Table 4.

[Embodiment 6] A plurality of photoconductors were prepared in the same manner as in Embodiment 5, except that the inner peripheral surface of the aluminum cylinder was not cut. The runout accuracy of the photoconductor after completion is measured, and the runout accuracy is 80 μm.
The sample was taken out and evaluated in the same manner as in Example 1. The results are shown in Table 4.

[Embodiment 7] A plurality of photoconductors were prepared in the same manner as in Embodiment 5 except that the inner peripheral surface of the aluminum cylinder was not cut. Measure the runout accuracy of the photoconductor after completion, and the runout accuracy is 100μ.
The sample of m was taken out and evaluated in the same manner as in Example 1. The results are shown in Table 4.

[Embodiment 8] A photoconductor was prepared in the same manner as in Embodiment 5 except that the inner peripheral surface and the outer peripheral surface of the aluminum cylindrical body were not cut.
Measure the runout accuracy of the photoconductor after completion, and the runout accuracy is 120
Those having a thickness of μm were extracted and evaluated in the same manner as in Example 1. The results are shown in Table 4.

[Examples 9 to 12] The charge generation layers of Examples 1 to 4 have strong peaks at 7.4 ° and 28.2 ° of the Bragg angle 2θ ± 0.2 ° in CuKα characteristic X-ray diffraction. Hydroxygallium phthalocyanine crystal 3.
5 parts of polyvinyl butyral resin (trade name: S-REC BX-1, manufactured by Sekisui Chemical Co., Ltd.) was mixed with a resin solution prepared by dissolving 19 parts of cyclohexanone, and dispersed for 3 hours with a sand mill using 1 mmφ glass beads. To prepare a dispersion liquid, in which 69 parts of cyclohexanone and 1 part of ethyl acetate are added.
Add 32 parts to dilute, dry at 100 ° C for 10 minutes,
Photoreceptors were prepared in the same manner as in Examples 1 to 4 except that the film thickness was 0.15 μm, and were evaluated in the same manner as in Example 1. The results are shown in Table 4.

[Examples 13 to 16] The protective layers in Examples 9 to 12 were surface-treated with a compound having the following structural formula (treatment amount: 7%), antimony-doped tin oxide fine particles, 50 parts.

[0118]

[Chemical 6] And 150 parts of ethanol are dispersed in a sand mill for 66 hours, 20 parts of polytetrafluoroethylene fine particles (average particle size 0.18 μm) are further added and dispersed for 2 hours, and then a resol type phenol resin (trade name) PL
-4804: Gunei Chemical Industry Co., Ltd.) was dissolved as a resin component in an amount of 30 parts to form a film on the charge transport layer as a preparation liquid by a dip coating method, and dried by hot air at 145 ° C. for 1 hour to give a film thickness. Example 9 except that a protective layer having a thickness of 3 μm was formed.
Photosensitive members were prepared in the same manner as in Nos. 12 to 12, and evaluated in the same manner as in Example 1. The results are shown in Table 4.

[Examples 17 to 20] The same evaluation as in Example 1 was carried out using the same charging roller as in Example 1 except that the outer diameter of the photosensitive member was changed to 40 mm. The deflection accuracy of the photoconductor was selected to be 50, 80, 100, 120 μm. The results are shown in Table 4.

[Comparative Examples 3 and 4] In Comparative Examples 1 and 2, the same charging roller as in Comparative Example 1 was used, except that the outer diameter of the photosensitive member was 40 mm, and the same evaluation was performed. The photoconductor deflection accuracy was selected to be 150 or 180 μm. The results are shown in Table 4.

[Examples 21 to 24] In Examples 1 to 4, the length of the photosensitive member was set to 260.5 mm, the evaluation machine was modified from Laser Shot 4000 manufactured by Hewlett Packard, and the longitudinal length of the charging roller was 230 mm. Evaluation was performed in the same manner as in Example 1 except that the above-mentioned one was used. The deflection accuracy of the photoconductor was selected to be 50, 80, 100, 120 μm. The results are shown in Table 4.

[0122]

[Table 4]

[0123]

According to the present invention, the charging member is brought into contact with the electrophotographic photosensitive member to charge the electrophotographic photosensitive member, the charging member is made of an elastic material, and the charging member surface is It moves with a speed difference with respect to the electrophotographic photoreceptor, and
In an electrophotographic photosensitive member used in an electrophotographic apparatus that carries conductive particles on at least the contact surface between the charging member and the electrophotographic photosensitive member, the electrophotographic photosensitive member has at least a photosensitive layer and a photosensitive layer on a cylindrical conductive support. An electrophotographic photosensitive member having a protective layer, wherein a drive transmission member and a bearing member are attached to the openings at both ends of the cylinder, and a shake precision when rotated about the central axis is 120 μm or less, and With the process cartridge and the electrophotographic apparatus having the electrophotographic photosensitive member, it was possible to eliminate the image defect due to the uneven charging.

[Brief description of drawings]

FIG. 1 is a sectional view of a charging device.

FIG. 2 is a configuration diagram of a process cartridge.

FIG. 3 is a layer structure of a photoreceptor.

[Explanation of symbols]

1 photosensitive body a developing area portion n which is the opposing portion of the photosensitive body 1 and the developing sleeve 6b charging nip portion 2 charging roller 2a core metal 2b elastic roller S1 charging bias applying power source 3 to the core metal 2a charging accelerating particles 4 regulating blade 5 Scanner (exposure device) 6 Developing device 6a Magnet roller 6b Developing sleeve S2 Developing bias applying power source 7 for developing sleeve 6b Transfer means b Transfer nip S3 Bias applying power source 8 for transfer roller 7 Fixing device 9 Removable to printer body Process cartridge 10 Attachment / detachment guide / holding member for process cartridge P Recording material 11 Protective layer 12 Charge transport layer 13 Charge generation layer 14 Conductive support 15 Binder layer 16 Undercoat layer

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) G03G 15/02 101 G03G 15/02 101 21/18 15/00 556 F term (reference) 2H035 CA05 CA07 CB02 CB03 CB04 CD14 CG03 2H068 AA03 AA04 AA05 AA06 AA54 BA58 BA61 BB07 BB08 BB29 BB30 BB31 BB33 BB34 BB35 BB58 CA05 CA33 FA12 FA27 2H071 BA04 BA13 CA02 CA05 DA02 DA06 DA08 DA09 DA15 DA26 2H200 FA21 GA16 GA23 DA21 DA23 MC01

Claims (10)

[Claims] 1. A charging member is brought into contact with an electrophotographic photosensitive member to charge the electrophotographic photosensitive member, the charging member is composed of an elastic body, and the surface of the charging member is relative to the electrophotographic photosensitive member. In the electrophotographic photosensitive member used in an electrophotographic apparatus in which conductive particles are carried on at least the contact surface between the charging member and the electrophotographic photosensitive member, the electrophotographic photosensitive member is a cylinder. At least a photosensitive layer and a protective layer are provided on a cylindrical conductive support, a drive transmission member and a bearing member are attached to the openings at both ends of the cylinder, and the shake accuracy when rotated about the central axis is 120 μm or less. An electrophotographic photoreceptor characterized by the above. 2. The electrophotographic photosensitive member according to claim 1, wherein the protective layer contains a curable resin and conductive particles. 3. The electrophotographic photosensitive member according to claim 2, wherein the curable resin is at least one of acrylic resin, phenol resin, epoxy resin, urethane resin, and siloxane resin. 4. The protective layer contains at least one of a fluorine atom-containing compound and a siloxane compound.
4. The electrophotographic photosensitive member according to any one of 1 to 3. 5. The electrophotographic photosensitive member according to claim 4, wherein the fluorine atom-containing compound is at least one selected from the group consisting of a fluorine-containing silane coupling agent, a fluorine-modified silicone oil and a fluorine-based surfactant. 6. The electrophotographic photosensitive member according to claim 4, wherein the siloxane compound is a siloxane compound represented by the following general formula. General formula [Chemical formula 1] (In the formula, A is a hydrogen atom or a methyl group, and A
The proportion of hydrogen atoms in the whole is 0.1 to 50%, and n is a positive integer of 0 or more. ) 7. The electrophotographic photosensitive member according to claim 1, wherein the protective layer contains lubricating particles. 8. The electrophotographic photosensitive member according to claim 7, wherein the lubricating particles are at least one selected from the group consisting of fluorine atom-containing resin particles, silicon particles, silicone particles, and alumina particles. 9. The electrophotographic photosensitive member according to claim 1 and at least one means selected from charging, exposing, developing and transferring are integrally supported, and are detachably attached to an image forming apparatus. A process cartridge characterized by being present. 10. An electrophotographic apparatus comprising the electrophotographic photosensitive member according to claim 1 and at least four means for charging, exposing, developing and transferring in an apparatus.