JP3423538B2 - Electrophotographic photoreceptor, process cartridge and electrophotographic apparatus - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic photoreceptor, a process cartridge and an electrophotographic apparatus having the electrophotographic photoreceptor, and more specifically, an electrophotographic photoreceptor having a surface layer containing a specific resin, and The present invention relates to a process cartridge having an electrophotographic photosensitive member and an electrophotographic apparatus.

[0002]

2. Description of the Related Art An electrophotographic method is disclosed in US Pat. No. 229769.
As shown in Japanese Patent Laid-Open No. 1, a photoconductive material is used which comprises a support whose electric resistance changes according to the amount of irradiation received during image exposure and which is coated with an insulating material in a dark place. The basic characteristics required for an electrophotographic photosensitive member using this photoconductive material are (1) being able to be charged to an appropriate potential in a dark place, (2) having a small potential dissipation in a dark place, and (3) ) Promptly dissipating the charge by light irradiation and the like.

Conventionally, selenium has been used as an electrophotographic photoreceptor.
Inorganic photoreceptors having a photosensitive layer containing an inorganic photoconductive compound such as zinc oxide and cadmium sulfide as a main component have been widely used. However, although these satisfy the above conditions (1) to (3), they are not always satisfactory in thermal stability, moisture resistance, durability and productivity.

In recent years, electrophotographic photoreceptors containing various organic photoconductive compounds as main components have been actively developed in order to overcome the drawbacks of inorganic photoreceptors. For example, US Pat.
No. 851 discloses a photoreceptor having a charge transport layer containing triallylpyrazoline, and US Pat. No. 3,871,880 discloses a charge generation layer comprising a derivative of a perylene pigment and 3
A photoconductor or the like comprising a charge transport layer made of a condensation product of propylene and formaldehyde is known.

Further, the organic photoconductive compound can freely select the photosensitive wavelength region of the electrophotographic photosensitive member depending on the compound. For example, in the case of an azo pigment, it is disclosed in JP-A-61-27.
2754 and JP-A-56-167759 disclose substances having high sensitivity in the visible region, and JP-A-57-19576 and JP-A-61-22.
Japanese Patent No. 8453 discloses compounds having sensitivity in the infrared region.

Of these materials, those exhibiting sensitivity in the infrared region are used in laser beam printers (hereinafter abbreviated as LBP) and LED printers, which have made remarkable progress in recent years, and their demand frequency is increasing.

Electrophotographic photoreceptors using these organic photoconductive compounds are used as function-separated photoreceptors in which a charge transport layer and a charge generating layer are laminated in order to satisfy both electrical and mechanical characteristics. Often. On the other hand, as a matter of course, the electrophotographic photosensitive member is required to have sensitivity, electrical characteristics, and optical characteristics according to the electrophotographic process applied.

Particularly in an electrophotographic photosensitive member that is repeatedly used, an electric or mechanical external force such as corona or direct charging, image exposure, toner development, transfer process and surface cleaning is directly applied to the surface of the electrophotographic photosensitive member. For,
Durability against them is also required.

Specifically, electrical deterioration due to ozone and nitrogen oxides during charging, mechanical deterioration in which the surface is abraded or scratched due to discharge during charging, rubbing of a cleaning member, and photosensitivity due to abrasion There is a demand for durability against deterioration of image quality due to developer (toner) being fixed to the body surface (hereinafter referred to as toner fusion).

Organic photoreceptors, which are different from inorganic photoreceptors and are often soft in terms of material, have poor durability against mechanical deterioration and are particularly eagerly desired to have improved durability.

Various attempts have been made to satisfy the durability characteristics required for the above-mentioned photoreceptor.

Polycarbonate resin having bisphenol A as a skeleton has been attracting attention as a resin which is often used for the surface layer and has good wear properties and electric characteristics. However, it is not possible to solve all the problems mentioned above and It has such a problem.

(1) It has poor solubility and shows good solubility only in a part of halogenated aliphatic hydrocarbons such as dichloromethane and 1,2-dichloroethane, and these solvents have a low boiling point. When a photoconductor is manufactured using a coating solution prepared with the above solvent, the coated surface is easily whitened. It also takes time to manage the solid content of the coating liquid.

(2) For solvents other than halogenated aliphatic hydrocarbons, it is partially soluble in tetrahydrafuran, dioxane, cyclohexanone or a mixed solvent thereof, but the solution gels in a few days. Is inferior in aging,
Not suitable for photoconductor manufacturing.

(3) Further, even if the above formulas (1) and (2) are improved, solvent cracks are likely to occur in the polycarbonate resin having bisphenol A as a skeleton.

(4) In addition, in the conventional polycarbonate resin, since the film formed of the resin has no lubricity, the photoconductor is easily scratched, and the cleaning setting is set to reduce the abrasion amount of the electrophotographic photoconductor. Image defects such as toner fusion may occur, or cleaning failure may occur due to early deterioration of the cleaning blade.

Regarding the solution stability mentioned in the above (1) and (2), a polycarbonate Z resin having a bulky cyclohexylene group as a structural unit of the polymer is used, or it is copolymerized with bisphenol Z, bisphenol C or the like. Has been solved by.

Solvent cracks can be solved by using a siloxane-modified polycarbonate or an ether-modified polycarbonate as disclosed in JP-A-6-51544 and JP-A-6-75415. . However, compared to conventional polycarbonate resins, these modified polycarbonates have a structure that has flexibility against internal stress in the polymer in order to prevent solvent cracks, and as a result, the mechanical properties of the polymer body are reduced. There was a drawback that the strength was reduced.

Furthermore, in recent years, a direct charging system as disclosed in JP-A-57-17826 and JP-A-58-40566, in which a voltage is directly applied to a charging member to apply a charge to an electrophotographic photosensitive member. Is becoming mainstream.

This is a method in which a roller-shaped charging member made of a conductive rubber or the like is directly brought into contact with an electrophotographic photosensitive member to apply an electric charge, and the amount of ozone generated is much smaller than that of a scorotron. About 80% of the current passed through the charger is wasted because it flows through the shield, whereas direct charging has the merit that it is very economical without this wasted amount.

However, the direct charging has a drawback that the charging stability is very poor because it is charged by the discharge according to Paschen's law. As a countermeasure against this, a so-called AC / DC charging system in which an AC voltage is superimposed on a DC voltage has been devised (Japanese Patent Laid-Open No. 63-149668).

Although this charging method improves the stability during charging, the amount of discharge on the surface of the electrophotographic photosensitive member is greatly increased due to the superposition of AC, and the scraped amount of the electrophotographic photosensitive member is increased. New defects have arisen, and not only mechanical strength but also electrical strength is required.

[0023]

The object of the present invention is to solve the problems in the case of having a conventional polycarbonate resin as a surface layer, to impart abrasion resistance and solvent crack resistance in a direct charging system at the same time, and Another object of the present invention is to provide an electrophotographic photosensitive member which is not easily adhered to the surface of the developer, has good electrophotographic characteristics, and is easy to manufacture, and a process cartridge and an electrophotographic apparatus having the electrophotographic photosensitive member.

[0024]

That SUMMARY OF THE INVENTION The present invention provides an electrophotographic photosensitive member having a photosensitive layer on an electroconductive substrate, wherein
The electronic member is charged by a charging member that is brought into contact with the electrophotographic photosensitive member.
Electrographic printer having contact charging means for charging true photoconductor
In an electrophotographic photosensitive member for a true device, the photosensitive layer is
The charge generation layer and the charge transport layer are laminated in this order from the side of the organic support.
Is a photosensitive layer, and the surface layer of the electrophotographic photoreceptor is the charge transport layer.
The electrophotographic photosensitive member is a transfer layer, and the surface layer of the electrophotographic photosensitive member contains a polymer represented by the following formula (1).

[0025]

[Chemical 4] (In the formula, X represents an alkylene group, R _{1 to} R ₃ each represent a hydrogen atom, a halogen atom, or an alkyl group, an alkenyl group or an aryl group which may have a substituent, and R ₄ represents the number of carbon atoms. 1 to 11 represent a perfluoro group, R _{5 to} R ₁₆ each represent a hydrogen atom, a halogen atom, or an alkyl group, an alkenyl group or an aryl group which may have a substituent, and m represents 0 to 10 An integer, n is an integer of 10 to 50, and 10 ≦ (m + n)
≦ 500 is satisfied. )

[0026]

BEST MODE FOR CARRYING OUT THE INVENTION In the above formula (1), the halogen atom includes a fluorine atom, a chlorine atom and a bromine atom, the alkyl group includes a methyl group, an ethyl group and a propyl group, and the alkenyl group. Examples thereof include a vinyl group, an allyl group and a butenin group, examples of the alkylene group include a methylene group, ethylene group and i-propylene group, and examples of the aryl group include a phenyl group, a naphthyl group and an anthryl group. Examples of the perfluoro group include a perfluoromethyl group, a perfluoroethyl group, a perfluorodecyl group and a perfluorooctadecyl group. Examples of the substituent which these may have include a halogen atom, an alkyl group and an aryl group as described above.

The polymer having a constitutional unit represented by the formula (1) used in the present invention can be obtained by polymerizing a fluorine-containing siloxane-modified bisphenol represented by the following formula (3) and an aromatic dicarboxylic acid.

At this time, it is preferable to prepare a copolymer with other general bisphenols such as bisphenol Z, bisphenol A, bisphenol C and bisphenol AF in consideration of solubility during polymerization. However, in this case, the constitutional unit represented by the formula (1) is 0.1 to 3 out of all the polymers.
It is preferably present at 0% by weight, more preferably 0.5.
10 to 10% by weight. If it is less than 0.1% by weight, the effect tends to be insufficient, and if it is more than 30% by weight, it tends to be extremely softened depending on the monomer to be copolymerized and it tends to be difficult to form a coating film. .

The aromatic dicarboxylic acid is preferably a mixture of terephthalic acid and isophthalic acid, and usually the ratio of terephthalic acid chloride to isophthalic acid chloride is determined in consideration of the solubility of the polymer. There is no dogma.
However, it should be noted that if the content of any of the chlorides is less than 30 mol%, the solubility of the synthesized polymer will be extremely lowered. Usually, it is preferable to synthesize at a ratio of 1/1.

[0030]

[Chemical 5] (In the formula, X represents an alkylene group, R _{1 to} R ₃ each represent a hydrogen atom, a halogen atom, or an alkyl group, an alkenyl group or an aryl group which may have a substituent, and R ₄ represents the number of carbon atoms. 1 to 30 represents a perfluoro group, R _{5 to} R ₁₂ each represent a hydrogen atom, a halogen atom, or an alkyl group, an alkenyl group or an aryl group which may have a substituent, and m and n are 0 or It is a positive integer and satisfies 10 ≦ (m + n) ≦ 500.) In the electrophotographic photosensitive member of the present invention, there are two kinds of polymers having the same constitutional unit represented by the formula (1). It may be a copolymer composed of another type of structural unit represented by the above formula (1).

Similar effects can be expected when X in the formulas (1) and (3) which is bonded to the oxygen atom is a silyl group having an alkylene group. Specific examples of the polymer containing the structural unit represented by the formula (1) are shown in Table 1, but are not limited thereto.

[0032]

[Table 1]

[0033]

[Table 2]

[0034]

[Table 3]

[0035]

[Table 4]

[0036]

[Table 5] In addition, examples of various bisphenols to be copolymerized include the following (b1) to (b-7), but are not limited thereto.

[0037]

[Chemical 6]

The electrophotographic photosensitive member according to the present invention is provided with the abrasion resistance and the solvent crack resistance at the same time in the direct charging system, and has the characteristics that the toner fusion does not easily occur.

The addition of the siloxane-modified polyarylate represented by the above formula (1) to the polyarylate as shown in the following (c-1) to (c-3) makes it possible to obtain a structure of siloxane itself or a blend of different polymers. It is presumed that due to the crystallization-inhibiting effect by the above, flexibility is imparted to the inside of the polymer, and the internal stress is dispersed even when a chemical that causes a solvent crack invades, and the crack is not generated.

[0040]

[Chemical 7]

On the other hand, the mechanical strength of the polymer is lowered,
It is expected that the abrasion resistance of the photoreceptor will be reduced, but it is actually improved. The reason for this is that the introduction of a siloxane bond into the skeleton of the arylate improves the AC charging resistance, which largely controls the abrasion resistance of the photoreceptor, and the increase in the amorphous region due to the inclusion of the siloxane-modified polyarylate. It is speculated that the energy is efficiently dissipated out of the system, but no confirmation has been obtained.

Further, the reason why the fusion of the toner does not occur due to the grafting of perfluoroalkyl to the siloxane is presumed to be that the surface energy is imparted to the photoconductor regardless of the durability.

Further, it has been found that the inclusion of the fluorine-containing siloxane-modified polyarylate significantly reduces the fluctuation amount of the potential when the photoreceptor is continuously operated.

The constitution of the electrophotographic photosensitive member used in the present invention will be described below.

The electrophotographic photosensitive member according to the present invention may be a single layer type in which the photosensitive layer contains the charge transport material and the charge generating material in the same layer or a laminated type in which the charge transport layer and the charge generating layer are separated. Although it is good, the laminated type is preferable in terms of electrophotographic characteristics.

The conductive substrate to be used may be any one having conductivity, and examples thereof include metals such as aluminum and stainless steel, metals provided with a conductive layer, paper, plastics, etc., and the shape is a sheet or a cylinder. Is mentioned.

When the image input such as LBP is laser light, a conductive layer may be provided for the purpose of preventing interference fringes due to scattering or covering scratches on the substrate. This can be formed by dispersing conductive powder such as carbon black and metal particles in a binder resin. The thickness of the conductive layer is 5
The thickness is preferably 40 μm, more preferably 10 to 30 μm.

An intermediate layer having an adhesive function is provided thereon. Examples of the material of the intermediate layer include polyamide, polyvinyl alcohol, polyethylene oxide, ethyl cellulose, casein, polyurethane and polyether urethane. These are dissolved in a suitable solvent and applied.
The thickness of the intermediate layer is preferably 0.05 to 5 μm, more preferably 0.3 to 1 μm.

A charge generation layer is formed on the intermediate layer.
Examples of the charge generating substance used in the present invention include selenium-tellurium, pyrylium, thiapyrylium dyes, phthalocyanine, anthanthrone, dibenzpyrenequinone, trisazo, cyanine, disazo, monoazo, indigo, quinacridone and asymmetric quinocyanine pigments. To be In the case of the function-separated type, the charge generation layer includes a homogenizer, ultrasonic dispersion, ball mill, vibrating ball mill, sand mill, attritor, roll mill, and liquid collision type together with 0.3 to 4 times the amount of the charge generation material as the binder resin and solvent. Disperse well using a method such as a high-speed disperser, and apply the dispersion.
It is formed by drying. The thickness of the charge generation layer is preferably 5 μm or less, more preferably 0.1 to 2 μm.

The charge transport layer is formed mainly by coating and drying a paint in which a charge transport material and a binder resin containing a polymer containing the constituent unit of the present invention are dissolved in a solvent.
Examples of the charge transport material used include triarylamine compounds, hydrazone compounds, stilbene compounds, pyrazoline compounds, oxazole compounds, triallylmethane compounds and thiazole compounds.

These are combined with 0.5 to 2 times the amount of binder resin and coated and dried to form a charge transport layer. The thickness of the charge transport layer is preferably 5 to 40 μm, more preferably 15 to 30 μm.

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

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

The formed electrostatic latent image is then developed by the developing means 5.
The toner-developed image is developed by the toner, and the developed toner-developed image is taken out from a paper feeding unit (not shown) between the photoconductor 1 and the transfer means 6 in synchronization with the rotation of the photoconductor 1 and fed to the transfer material 7, The images are sequentially transferred by the transfer means 6.

The transfer material 7 having undergone the image transfer is separated from the surface of the photoconductor and introduced into the image fixing means 8 to undergo the image fixing, so that it is printed out to the outside of the apparatus as a copy.

The surface of the photoconductor 1 after the image transfer is cleaned by the cleaning means 9 to remove the residual toner after transfer, and the pre-exposure light 10 from the pre-exposure means (not shown).
It is used for repeated image formation after being neutralized by. If the primary charging means 3 is a contact charging means using a charging roller or the like, pre-exposure is not always necessary.

In the present invention, among the constituent elements such as the electrophotographic photosensitive member 1, the primary charging means 3, the developing means 5 and the cleaning means 9, a plurality of components are integrally combined as a process cartridge, The process cartridge may be detachably attached to the main body of an electrophotographic apparatus such as a copying machine or a laser beam printer. For example, at least one of the primary charging unit 3, the developing unit 5, and the cleaning unit 9 is integrally supported together with the photosensitive member 1 to form a cartridge, which can be attached to and detached from the apparatus main body by using a guide unit such as a rail 12 of the apparatus main body. Process cartridge 1
It can be 1.

When the electrophotographic apparatus is a copying machine or a printer, the image exposure light 4 is reflected light or transmitted light from the original, or the original is read by a sensor, converted into a signal, and the image exposure is performed in accordance with this signal. Laser beam scanning,
It is the light emitted by the driving of the LED array and the driving of the liquid crystal shutter array.

On the other hand, when used as a printer for a facsimile, the image exposure light 4 becomes exposure light for printing the received data. FIG. 2 is a block diagram showing an example of this case.

The controller 14 controls the image reading section 13 and the printer 22. The entire controller 14 is controlled by the CPU 20. The read data from the image reading unit 13 is transmitted to the partner station through the transmission circuit 16. The data received from the partner station is sent to the printer 22 through the receiving circuit 15. Predetermined image data is stored in the image memory. The printer controller 21 controls the printer 22. 17 is a telephone.

The image received from the line 18 (image information from a remote terminal connected via the line) is demodulated by the receiving circuit 15, and then the image information is decoded by the CPU 20 and sequentially stored in the image memory 19. To be done. Then, when at least one page of image is stored in the memory 19, the image of that page is recorded. The CPU 20 reads out one page of image information from the image memory 19, and the printer controller 21 decodes the decoded one page of image information. Send image information. The printer controller 21 is
When the image information of one page is received from the CPU 20, the printer 22 is controlled to record the image information of the page. The CPU 20 is receiving the next page during recording by the printer 22.

In this way, the image is received and recorded.

The electrophotographic photoreceptor of the present invention can be used not only in electrophotographic copying machines but also in laser beam printers, C
It can be widely used in electrophotographic application fields such as RT printers, LED printers, liquid crystal printers, and laser plate making.

A description will be given below according to an embodiment. The middle part of an Example represents a weight part.

[Example 1] An aluminum cylinder having a diameter of 30 mm and a diameter of 254 mm was used as a support, and a coating material composed of the following materials was applied to the support by a dip coating method and heat-cured at 140 ° C for 30 minutes to obtain 15 µm. The conductive layer of was formed.

Conductive pigment: S _n O ₂ coated barium sulfate 10 parts Resistance adjusting pigment: titanium oxide 2 parts Binder resin: phenol resin 6 parts Leveling material: silicone oil 0.001 part Solvent: methanol, methoxypropanol 0. 2 / 0.8 20 copies

Then, a solution prepared by dissolving 3 parts of N-methoxymethylated nylon and 3 parts of copolymerized nylon in a mixed solvent of 65 parts of methanol and 30 parts of n-butanol was applied thereon by a dip coating method to give a thickness of 0.5 μm. Was formed.

Next, oxytitanium phthalocyanine (TiOPc) having strong peaks at Bragg angles 2θ ± 0.2 ° of CuKα characteristic X-ray diffraction of 9.0 °, 14.2 °, 23.9 ° and 27.1 °. ) 4 parts and 2 parts of polyvinyl butyral (trade name: S-REC BM2, manufactured by Sekisui Chemical Co., Ltd.) and 60 parts of cyclohexanone are dispersed for 4 hours in a sand mill using φ1 mm glass beads, and then 100 parts of ethyl acetate are added to form a charge generation layer. A dispersion was prepared.
This was applied by a dip coating method to form a 0.2 μm charge generation layer.

Next, 9 parts of an amine compound having the following structural formula,

[0070]

[Chemical 8] 1 part of amine compound having the following structural formula

[0071]

[Chemical 9] And the sample No. of Table 2. 10 parts of the polymer of the combination described in 1 was dissolved in a mixed solvent of 30 parts of monochlorobenzene and 70 parts of dichloromethane. This paint was applied by dip coating method and dried at 120 ° C for 2 hours to 25 μm.
Was formed on the charge transport layer.

Next, the evaluation will be described.

The device is a Hewlett-Packard LBP
"Laser Jet 4 plus" (Process speed 7
1 mm / sec) was modified and used. In the modification, the constant current control was used for the primary charging control and the constant voltage control was used. The produced electrophotographic photosensitive member was subjected to paper passing durability (HH durability) at 28 ° C. and 90% RH with this apparatus. The sequence is set to an intermittent mode in which the printing is stopped once for each sheet.

When the toner was used up, the toner was replenished and the toner was durable until a problem appeared on the image. At this time, before endurance and paper passing endurance 2
The bright portion potential (Vl) after 000 sheets were measured, and the difference was defined as the potential fluctuation. At the same time, the abrasion amount (film thickness) of the photoconductor was measured from the initial stage of durability up to 10,000 sheets, and the abrasion amount per 1000 sheets was shown.

Further, except that continuous printing is performed without stopping the sequence, 10,000 sheets of paper are endured under the same conditions, and when a solid black image is output every 500 sheets, the toner is on the surface of the photoconductor. It was confirmed that the image adhered to the film and did not cause image defects (white spots). Further, regarding the solvent cracking property, sebum was adhered to the surface and left for 48 hours, and the presence or absence of solvent cracking was observed by microscopic observation.

The results are shown in Table 3.

[0077]

[Table 6]

[0078]

[Chemical 10]

[Examples 2 to 7] Sample No. 2 in Table 2 was used as the binder of the charge transport layer of Example 1. An electrophotographic photosensitive member was prepared and evaluated in the same manner as in Example 1 except that 2 to 7 were used. The results are shown in Table 3.

[0080]

[Table 7]

[Comparative Examples 1 to 5] As the binder of the charge transport layer of Example 1, the sample No. An electrophotographic photosensitive member was prepared and evaluated in the same manner as in Example 1 except that those of 8 to 12 were used. The results are shown in Table 5.

[0082]

[Table 8]

[0083]

[Table 9]

[0084]

[Table 10]

[0085]

[Table 11]

[0086]

According to the present invention, an electrophotographic photosensitive member which imparts solvent crack resistance while maintaining abrasion resistance in a direct charging system, is less likely to cause toner fusion, and has little potential fluctuation, and the electron It has become possible to provide a process cartridge having a photographic photoreceptor and an electrophotographic apparatus.

[Brief description of drawings]

FIG. 1 is a diagram showing an example of a schematic configuration of an electrophotographic apparatus having a process cartridge having an electrophotographic photosensitive member of the present invention.

FIG. 2 is a diagram showing an example of a block diagram of a facsimile having the electrophotographic photosensitive member of the present invention.

[Explanation of symbols]

1 Electrophotographic photoreceptor of the present invention 2 axes 3 Primary charging means 4 Image exposure light 5 Developing means 6 Transfer means 7 Transfer material 8 Image fixing means 9 Cleaning means 10 Pre-exposure light 11 Process cartridge 12 rails 13 Image reading section 14 Controller 15 Receiver circuit 16 Transmitter circuit 17 telephone 18 lines 19 Image memory 20 CPU 21 Printer controller 22 Printer

─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP 62-139561 (JP, A) JP 62-139557 (JP, A) JP 7-295340 (JP, A) JP 6- 89038 (JP, A) JP-A-3-6567 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) G03G 5/05 101

Claims (3)

(57) [Claims] 1. An electrophotographic photoreceptor having a photosensitive layer on a conductive support, comprising a contact charging means for charging the electrophotographic photoreceptor by a charging member brought into contact with the electrophotographic photoreceptor. In the electrophotographic photosensitive member for an electrophotographic apparatus, the photosensitive layer is a photosensitive layer in which a charge generation layer and a charge transport layer are laminated in this order from the conductive support side, and the surface layer of the electrophotographic photosensitive member is the charge layer. An electrophotographic photoreceptor, which is a transport layer, wherein the surface layer of the electrophotographic photoreceptor contains a polymer represented by the following formula (1). [Chemical 1] (In the formula, X represents an alkylene group, R _{1 to} R ₃ each represent a hydrogen atom, a halogen atom, or an alkyl group, an alkenyl group or an aryl group which may have a substituent, and R ₄ represents the number of carbon atoms. 1 to 11 represent a perfluoro group, R _{5 to} R ₁₆ each represent a hydrogen atom, a halogen atom, or an alkyl group, an alkenyl group or an aryl group which may have a substituent, and m represents 0 to 10 It is an integer, n is an integer of 10 to 50, and 10 ≦ (m + n)
≦ 500 is satisfied. ) 2. The electrophotographic photosensitive member according to claim 1, and a contact charging unit for charging the electrophotographic photosensitive member integrally by a charging member brought into contact with the electrophotographic photosensitive member, A process cartridge characterized by being detachable from the main body of the electrophotographic apparatus. 3. The electrophotographic photosensitive member according to claim 1, the charging unit, the image exposing unit, the developing unit and the transfer unit, wherein the charging unit is a charging member brought into contact with the electrophotographic photosensitive member. An electrophotographic apparatus comprising a contact charging means for charging an electrophotographic photosensitive member.