JPH10333346A - Electrophotographic photoreceptor and electrophotographic device using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To attain high-speed operation of an electrophotographic device and to prevent trouble such as fogging or the lowering of image density by incorpo rating a specified polycarbonate resin into the surface layer of an electrophotographic photoreceptor. SOLUTION: A polycarbonate-acrylic graft copolymer represented by the formula is incorporated into the surface layer of an electrophotographic photoreceptor. In the formula, X is H, 1-4C lower alkyl or halogen, (a) and (b) are integers of 0-4, Y is a single bond, an ether bond, 1-5C alkylene, 1-5C alkylidene, -S-, -SO-, -SO2 -, etc., Z is a single bond, -COO- or -NH-, R<1> is H or methyl, (n) is an integer of 2-40, preferably 3-20, (l) is 30-41, (m) is 10-500, (k) is an integer of 1-10, R<2> is an acrylate side chain and (n) is an integer of 2-40.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic photoreceptor which can be widely used in electrophotographic applications such as an electrophotographic copying machine, a laser beam printer, a facsimile, a CRT printer, and an electrophotographic plate making system. The present invention relates to an electrophotographic apparatus provided with a photoreceptor.

[0002]

2. Description of the Related Art In an image forming apparatus such as a copying machine or a printer, an electrostatic latent image carrier such as a photosensitive drum is charged by a charging device, and an image is exposed to the charged area to form an electrostatic latent image.
Developing the latent image into a visible image, transferring this to a transfer material,
Has established.

[0003] Various types of charging devices are known, but they are broadly classified into corona charging devices utilizing corona discharge and contact charging devices such as charging brushes and charging rollers.

A charging device using corona discharge has an advantage that stable charging can be performed. However, since a large amount of ozone is generated, there is a problem that deterioration of a photoreceptor is caused or a human body is adversely affected. And a contact charging device which generates a significantly smaller amount of ozone than a corona discharge device (Japanese Patent Application Laid-Open Nos. 63-149668 and 63-14).
9669, JP-A-63-168667, etc.) are being adopted.

An electrophotographic photoreceptor is generally constituted by providing a photoconductive film on a conductive cylindrical substrate, and aluminum is often used as the conductive substrate.

[0006] Recently, as the size of the electrophotographic apparatus has been reduced, the size of the electrophotographic photoreceptor has also been reduced, and the aluminum cylinder having a diameter of 30 as a conductive support has become mainstream. I have. In order to further reduce the size, development of a photosensitive drum using a cylinder of φ24, φ16 or the like is also being studied.

Conventionally, such a small-diameter photosensitive drum has been used for a low-speed machine. However, in order to meet the demands for miniaturization, space saving, and cost reduction of a copying machine or a printer body, a relatively high printing speed is required. It is being used for fast models.

[0008]

However, according to such a conventional technique, the amount of abrasion of the photosensitive layer by running tends to increase in the charging method using the contact charging device as compared with the corona charging method, and the surface of the photosensitive layer tends to increase. Improvement was required.

Further, as the diameter of the photosensitive drum is reduced and the print speed is increased, the number of rotations of the photosensitive drum per print increases, and in this regard, the amount of the photosensitive layer scraped by running tends to increase. Improvement of the photosensitive layer surface has been demanded.

Furthermore, in the contact charging method, the charging start voltage of the contact charger decreases as the film thickness of the photosensitive layer decreases, so that the smaller the film thickness of the photosensitive layer is, the smaller the film thickness of the photosensitive layer is. The amount increases and the potential increases.

For this reason, when the photosensitive layer is scraped off by running, the charging potential tends to increase, and when the charging potential increases, the light potential after exposure and the residual potential after slow exposure are increased. As a result, there is a problem that a fog image is generated in a copying machine, and a remarkable decrease in image quality such as a decrease in image density is observed in a printer.

Accordingly, the present invention has been made in view of the above-mentioned circumstances, and is directed to a contact charging system in which a photosensitive drum is brought into contact with a surface thereof and charged, and even if a small-diameter photosensitive drum having a diameter of 30 or less is used. It is an object of the present invention to provide an electrophotographic photoreceptor which is small in size, can be operated at high speed, and is free from inconveniences such as fog and image density, and an electrophotographic apparatus using the same.

[0013]

According to the present invention, there is provided an electrophotographic photoreceptor having a contact charging, exposure, development, transfer,
In an electrophotographic photoreceptor of an electrophotographic apparatus which is sequentially printed by each fixing process, the following general formula (I)

[0014]

Embedded image [However, in the general formula (I), X represents a hydrogen atom,
A and b represent an integer of 0 to 4; Y represents a single bond, an ether bond, an alkylene group and an alkylidene group having 1 to 5 carbon atoms, and a carbon atom having 5 carbon atoms. -15 cycloalkylene and cycloalkylidene groups, and -S- bond,
Z represents a single bond, a -COO-bond and a -NH-bond, and R ¹ represents a -SO- bond or a -SO ₂ -bond;
Represents a hydrogen atom or a methyl group, n represents an integer of 2 to 40, preferably 3 to 20, l represents 30 to 41, m represents 10 to 500, and k represents an integer of 1 to 10. . R ² is an acrylate side chain, and n represents an integer of 2 to 40. An electrophotographic photoreceptor comprising a polycarbonate acrylic graft copolymer represented by the formula:

Further, the electrophotographic apparatus of the present invention has an electrophotographic photosensitive member having a surface layer containing the polycarbonate copolymer having the above structure and a charging process by contact charging, and the electrostatic latent image is formed on the electrophotographic photosensitive member. , A developing means for developing and visualizing the electrophotographic photoconductor on which the electrostatic latent image is formed, and a means for cleaning the electrophotographic photoconductor.

The conductive support of the electrophotographic photosensitive member is, for example, a cylindrical cylinder having a diameter of 30 mm or less, and the continuous rotation speed of the electrophotographic photosensitive member is 0.25 revolutions per second or more.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The electrophotographic photoreceptor of the present invention contains a polycarbonate-based acrylic graft copolymer in a surface layer. Here, “surface layer” means a photosensitive layer when the photosensitive layer on the conductive support is a single layer type, and a photosensitive layer farthest from the conductive support when the photosensitive layer is a laminated layer. Means
When a protective layer is provided on the photosensitive layer, it means the protective layer.

The polycarbonate acrylic graft copolymer used in the present invention preferably has the structure of the general formula (I).

The acrylate-containing polycarbonate-based graft copolymer used in the present invention has an acrylate in a side chain and has an acrylic resin macromonomer represented by the general formula (II) and a polycarbonate oligomer represented by the general formula (III). Obtained by polycondensing a prepolymer obtained by polycondensation with an aromatic dioxane compound represented by the general formula (IV), and having a structure in which an acrylate-containing side chain hangs from a main chain. doing.

Here, the general formula (II) is

[0021]

Embedded image [However, in the formula, Z, R ¹ , R ² and m are the same as those in the general formula (I). General formula (III) is

[0022]

Embedded image Wherein X, Y, a, and b are the same as those in the general formula (I), and P is an integer of 2 to 15. And the general formula (IV) is

[0023]

Embedded image Wherein X, Y, a and b are the same as defined in the above general formula (I)
Is the same as ].

Specific examples of the structure of R ² include the following compounds, but the present invention is not limited to these examples.

[0025]

Embedded image The polycarbonate oligomer represented by the general formula (III) can be obtained from an aromatic dioxane compound represented by the general formula (IV) such as bis-2- (4-hydroxyphenyl) -propane (also called bisphenol A). . Specific examples of the aromatic dioxane compound include the following compounds, but the present invention is not limited to these examples.

[0026]

Embedded image In the electrophotographic photoreceptor of the present invention, one type of the polycarbonate-based acrylic graft copolymer may be used alone, or two or more types may be used in combination. If desired, other binder resin components such as polycarbonate may be contained as long as the object of the present invention is not impaired. Further, additives such as an antioxidant may be contained.

The cylindrical conductive support used in the electrophotographic photoreceptor of the present invention may be any conductive support, for example, a metal or alloy such as aluminum or stainless steel, or a conductive layer. Metal, plastic, paper and the like.

An undercoat layer having a barrier function and an adhesive function can be provided between the conductive support and the photosensitive layer.

As materials for the undercoat layer, polyvinyl alcohol, polyethylene oxide, ethylene cellulose,
Methyl cellulose, casein, polyamide, glue, gelatin and the like are used. These materials are dissolved in a suitable solvent and coated on a conductive support. The thickness is preferably from 0.2 to 5.0 μm.

Further, when the image input is a laser beam, a conductive layer may be provided as necessary between the conductive support and the undercoat layer in order to prevent interference fringes due to scattering.
This conductive layer can be formed by dispersing conductive powder of carbon black, metal particles or metal oxide in a suitable binder resin.

The thickness of the conductive layer is preferably 5 to 30 μm.
Examples of the charge generating material include azo pigments, quinone pigments, quinocyanic pigments, perylene pigments, indigo pigments, azulenium pigments, phthalocyanine pigments,
Selenium-tellurium, pyrylium dyes and thiopyrylium dyes are preferably used.

These may be used alone or in a combination of two or more.

When the photosensitive layer is of a laminated type, the charge generation layer is formed by vacuum evaporation, or the charge generation material is mixed with a binder resin in a solvent in a solvent such as a homogenizer, an ultrasonic wave, a ball mill, a vibrating ball mill, a sand mill, and an atomizer. Writer,
It can be formed by dispersing with a method such as a roll mill, coating and drying. The thickness of the charge generation layer formed in this manner is 0.01 to 3 μm, and in particular, 0.1 μm.
The range of from 02 to 1 μm is preferred.

The binder resin that can be used when forming the charge generating layer by coating can be selected from a wide range of resins, and can be an organic photoconductive polymer such as poly-N-vinylcarbazole, polyvinylanthracene, or polyvinylpyrene. You can choose from. Preferable examples include polyvinyl butyral, polyarylate (such as a condensation polymer of bisphenol A and phthalic acid), polycarbonate, polyester, phenoxy resin, polyvinyl acetate, acrylic resin, polyacrylamide resin, polyamide, polyvinyl pyridine, and cellulose resin. Examples thereof include insulating resins such as urethane resins, epoxy resins, casein, polyvinyl alcohol, and polyvinylpyrrolidone.

Specific solvents that can be used for these binder resins include alcohols such as methanol, ethanol, and isopropanol; acetone;
Ketones such as methyl ethyl ketone and cyclohexanone; amides such as N, N-dimethylformamide and N, N-dimethylacetamide; sulfoxides such as dimethyl sulfoxide; ethers such as tetrahydrofuran, dioxane and ethylene glycol monomethyl ether; methyl acetate; Ethers such as ethyl, aliphatic halogenated hydrocarbons such as chloroform, methylene chloride, dichloroethylene, carbon tetrachloride, and trichloroethylene, or aromatics such as benzene, toluene, xylene, monochlorobenzene, and dichlorobenzene. Can be used.

Examples of the charge transport material include polycyclic aromatic compounds such as biphenylene, anthracene, pyrene, and phenanthrene; nitrogen-containing cyclic compounds such as indole, carbazole, oxadiazole, and pyrazoline; hydrazone compounds; and styryl compounds. It is preferably used.

These may be used alone or in a combination of two or more.

When the photosensitive layer is of a laminated type, the charge transporting layer can be formed by dissolving a charge transporting substance in a solvent together with a suitable binder resin if necessary, and then coating and drying. The thickness of the charge transport layer is preferably in the range of 5 μm to 50 μm, and particularly preferably in the range of 8 μm to 35 μm.

Examples of the binder resin that can be used for forming the charge transport layer include acrylic resins, polyarylates, polyesters, polycarbonates, polystyrenes, acrylonitrile-styrene copolymers, acrylonitrile-butadiene copolymers, and polyvinyl resins when the surface layer is not used. Butyral, polyvinyl formal, polysulfone, polyacrylamide, polyamide,
Examples thereof include insulating resins such as chlorinated rubber, and organic photoconductive polymers such as poly-N-vinylcarbazole, polyvinylanthracene, and polyvinylpyrene.

Further, as the solvent, for example, those described above can be used.

On the other hand, when the photosensitive layer has a single-layer structure, the above-described charge generating substance and a charge transporting substance in an amount of 2 to 10 times the amount thereof are mixed with a suitable binder resin in a solvent, and coated and dried. Can be formed. The film thickness is from 5 μm
35 μm, particularly preferably in the range of 10 μm to 30 μm.

In the photosensitive layer of the present invention, a lubricating powder such as a fluororesin powder, a polyolefin-based resin powder, a carbon fluoride powder, or an ozone produced by corona discharge is used for the purpose of protecting against abrasion and scratches. A radical scavenger, an antioxidant, an ultraviolet absorber, and the like can be added for the purpose of preventing deterioration of the photosensitive layer from a generated substance, repeated exposure, and charging.

The electrophotographic photoreceptor of the present invention is generally applied to electrophotographic apparatuses such as copiers, laser printers, LED printers, and liquid crystal shutter printers. Further, displays, recording, light printing, and plate making using electrophotographic technology are applied. And facsimile machines.

Next, an electrophotographic apparatus having the electrophotographic photosensitive member of the present invention will be described.

FIG. 1 shows a schematic configuration of a general electrophotographic apparatus using the electrophotographic photosensitive member of the present invention.

In the figure, reference numeral 1 denotes an electrophotographic photosensitive member according to the present invention, which is driven to rotate around an axis 1a in a direction indicated by an arrow at a predetermined speed.

On the electrophotographic photosensitive member 1, an electrostatic latent image is formed by a latent image forming means. The latent image is formed by, for example, uniformly charging the peripheral surface with a predetermined positive or negative potential by a roller-shaped contact charging means 2, and then performing image exposure L (slit exposure or laser beam scanning exposure) by an image exposure means (not shown). Etc.). Thus, an electrostatic latent image corresponding to the exposure image is sequentially formed on the peripheral surface of the photoconductor.

The formed electrostatic latent image is then developed.
The toner-developed image is transferred between the electrophotographic photosensitive member 1 and the transfer unit 5 from a paper feeding unit (not shown) by, for example, a roller-shaped transfer unit 5 in synchronization with the rotation of the electrophotographic photosensitive member 1. The recording material P is sequentially transferred onto the surface of the taken and fed recording material P. The recording material P to which the image has been transferred is separated from the photoreceptor surface, introduced into the image fixing means 8, subjected to image fixing, and printed out of the apparatus.

The untransferred toner and paper powder are scraped off the surface of the electrophotographic photosensitive member 1 after image transfer by the cleaning means 6.

As the contact charging means for the electrophotographic photosensitive member 1, a roller, a brush or a blade may be used.

As the electrophotographic apparatus, a plurality of components such as the above-described electrophotographic photosensitive member, developing means, and cleaning means are integrally connected as an apparatus unit, and this unit is attached to the apparatus body. You may comprise detachably.

Hereinafter, specific examples of the synthesis of a polycarbonate-based acrylic graft copolymer, the synthesis of a polycarbonate oligomer, and (3) the production of a polycarbonate-based graft copolymer applicable to the present invention will be described, but the present invention is not limited thereto. It is not something to be done. (A) Synthesis of polycarbonate-based acrylic graft copolymer (1) Synthesis of polymethyl methacrylate macromonomer Methyl methacrylate 2 in 400 ml of tetrahydrofuran
00g, azobisisobutyronitrile (polymerization initiator)
2.3 g and 12.7 g of thiomalic acid (chain transfer agent) were dissolved, heated to 60 ° C., and reacted for 3 hours. The reaction product was poured into 4 liters of petroleum ether with stirring, and the polymer was precipitated, filtered and dried. Next, the obtained polymer was dissolved in methylene chloride, washed with water, and evaporated to dryness to obtain polymethyl methacrylate (PMMA) macromonomer having a polymerization degree of 111 to 113.

(2) Synthesis of Polycarbonate Oligomer Bisphenol A (60 kg) is dissolved in 400 L of a 5% aqueous solution of sodium hydroxide to prepare an aqueous solution of bisphenol A in sodium hydroxide. Then, the aqueous sodium hydroxide solution of bisphenol A and methylene chloride kept at room temperature were introduced at a flow rate of 138 liters / hour and 69 liters / hour into a tubular reactor having an inner diameter of 10 mm and a length of 10 m through an orifice plate. Phosgene is blown in parallel at a flow rate of 10.7 kg / hour, and the reaction is continuously performed for 3 hours. The tubular reactor used here is a double tube, and the outlet temperature of the reaction solution is kept at 25 ° C. by passing cooling water through the jacket. The pH of the discharged liquid is set to be 10 to 11. The resulting reaction solution was allowed to stand to separate and remove the aqueous phase, and the methylene chloride phase (2
20 liters), 342 liters of methylene chloride was further added thereto, and the mixture was sufficiently stirred to obtain a polycarbonate oligomer (concentration: 220 g / liter). The degree of polymerization of the obtained oligomer is 3 to
It was 4.

(3) Production of polycarbonate graft copolymer Acrylic resin macromonomer 69 obtained in (1) above
g and 28 g of the polycarbonate oligomer obtained in the above (2) were dissolved in 200 ml of methylene chloride, and 2.1 ml of triethylamine was added. The mixture was reacted for 1 hour with stirring, washed with hydrochloric acid, and the organic phase was separated. Thus, a prepolymer solution was obtained.

Methylene chloride was added to the obtained prepolymer solution to make 400 ml, and 1.0 g of pt-butylphenol (molecular weight modifier) was added to obtain an organic solvent solution. Meanwhile, 10.7 g of bisphenol A, 6.5 g of sodium hydroxide, and 0.07 ml of triethylamine were dissolved in water to form an aqueous solution. Interfacial polycondensation was performed while stirring 110 ml of this aqueous solution and the organic solvent solution, and washing was performed.
Separation gave a polycarbonate-based graft copolymer.

An acrylate macromonomer in which R ² in the above general formula is changed (R ¹ is always unified with a methyl group)
Various polycarbonate graft copolymers were obtained in the same manner as the above polycarbonate graft copolymers by using polycarbonate oligomers in which Xa, Xb, and Y were changed. Table 1 shows the results.

[0057]

[Table 1]

[0058]

【Example】

(Example 1) As a conductive support, 30φ, 260 m
m, an aluminum cylinder having a wall thickness of 0.75 mm was prepared. On this, layers having the following structures were sequentially laminated and applied to form a photosensitive layer.

100 parts (parts by weight, hereinafter the same) of a conductive powder obtained by coating tin oxide containing 10% of antimony oxide to titanium oxide at 75% by weight was mixed with 100 parts of a resole phenolic resin and methanol. In addition to a solution consisting of 30 parts of methylcellosolve and 100 parts of methylcellosolve, the mixture was well dispersed in a ball mill to form a coating. This paint is dip-coated on a substrate, and cured by heating at 140 ° C. for 30 minutes.
Was provided. On top of this, a polyamide resin (6-6)
6-64-124 element nylon copolymer) 1 part, and 8
3 parts of a nylon resin (methoxymethylated nylon, methoxylation rate: about 30%) were mixed with 50 parts of methanol and 4 parts of butanol.
A coating solution dissolved in a solvent consisting of 0 parts was dip-coated,
After drying at 10 ° C. for 10 minutes, a 0.5 μm undercoat layer was provided.

Next, a substance having the following structure is used as a charge generating substance.

[0061]

Embedded image 1 part and polyvinyl butyral resin (manufactured by Sekisui Chemical, BX-
1) 2 parts were added to 60 parts of cyclohexanone, dispersed by a sand mill for 2 hours, diluted with 90 parts of methyl ethyl ketone, and dip-coated on the undercoat layer.
After drying at 10 ° C. for 10 minutes, a 0.2 μm charge generation layer was provided.

Next, 7 parts of a compound represented by the following structure as a charge transporting substance:

[0063]

Embedded image And Table 1. Compound No. 10 parts of the polycarbonate-based acrylic graft copolymer in 1
And 25 parts of dichloromethane, this solution was applied onto the charge generation layer by dip coating, dried at 100 ° C. for 1 hour, and dried.
A 5 μm charge transport layer was provided. Next, this photoconductor is incorporated into a process cartridge having a configuration as illustrated in FIG. 2 and further mounted on a laser beam printer having a print speed of eight sheets (A4) per minute.
Continuous printing was performed on 10,000 sheets, and the quality of the printed image and the amount of change in the thickness of the photosensitive layer were measured.

The condition of this electrophotographic apparatus is a roller-type contact charging method. As a roller charger, a conductive rubber layer of 10 ⁴ to 10 ⁵ Ωcm such as EPDM is provided on the outer periphery of a cored bar and the outer periphery thereof is provided. consisting of hydrin, etc. 10 ^7-1
0 ⁹ a resistive layer provided in the order of [Omega] cm, further 10 ^7-1
The one provided with a blocking layer of 0 ¹⁰ Ωcm as a surface layer was used.

Then, the roller charger is attached to the photosensitive member,
Contact was made at a total pressure of 800 g, and the rotation was driven. The conditions of the applied voltage were a DC applied voltage of 700 V, an AC applied voltage of 550 Hz, and a peak-to-peak voltage of 2000 V.

The rotation speed of the photosensitive member was 0.5 rotation per second.

Table 2 shows the results.

(Embodiment 2) Conductive support 2 of photosensitive drum
Using a 4φ, 250 mm, 0.75 mm thick aluminum cylinder, a photosensitive drum was prepared in the same manner as in Example 1.

Further, this photosensitive member was incorporated into a process cartridge having a structure as illustrated in FIG. 2, and was mounted on a laser beam printer having a print speed of four sheets per minute (A4). The same evaluation was performed.

The condition of the applied voltage of the roller charger is as follows: DC applied voltage is 550 V, AC applied voltage frequency is 150 H
z, the peak-to-peak voltage was 1500 V.

The rotation speed of the photosensitive member was 0.3 rotation per second.

Table 2 shows the results.

(Embodiment 3) Conductive support 3 of photosensitive drum
A photosensitive drum was prepared in the same manner as in Example 1 using an aluminum cylinder having a diameter of 0φ, 260 mm, and a thickness of 0.75 mm.

Further, this photosensitive drum is incorporated in a process cartridge having a configuration as illustrated in FIG.
Further, this was mounted on a laser beam printer having a print speed of 4 sheets per minute (A4), and the same evaluation as in Example 1 was performed.

The condition of the applied voltage of the roller charger is as follows: DC applied voltage is 600 V, AC applied voltage frequency is 250 H
z, the peak-to-peak voltage was 1500 V.

The rotation speed of the photosensitive member was 0.26 rotations per second.

Table 2 shows the results.

Comparative Example 1 A photosensitive drum similar to that of Example 1 was prepared, except that a polycarbonate resin comprising a repeating unit having the following structure was used, and the same evaluation as in Example 1 was performed.

Table 2 shows the results.

[0080]

Embedded image (Comparative Example 2) A photosensitive drum similar to that of Example 1 was prepared except that a polycarbonate resin having a repeating unit having the following structure was used, and the same evaluation as that of Example 1 was performed.

Table 2 shows the results.

[0082]

Embedded image (Examples 4 to 7) Table 1. Compound No. A photoreceptor was prepared and examined in the same manner as in Example 2 except that 2, 3, 4, and 5 polycarbonate-based acrylic graft copolymers were used.

Table 2 shows the results.

(Embodiment 8) Conductive support 2 of photosensitive drum
A photosensitive drum was prepared in the same manner as in Example 1, except that an aluminum cylinder having a diameter of 4 mm and a thickness of 250 mm and a thickness of 0.75 mm was used, and a substance having the following structure was used as a charge generating substance.

[0085]

Embedded image The photosensitive member was incorporated into a process cartridge having a configuration as illustrated in FIG. 2, and was mounted on a copying machine having a print speed of four sheets per minute (A4). Was done.

The conditions of the applied voltage of the roller charger are as follows: DC applied voltage is 650 V, AC applied voltage frequency is 400H
z, the peak-to-peak voltage was 2000v. The rotation speed of the photosensitive member was 0.3 rotation per second.

Table 2 shows the results.

(Examples 9 to 11) Table 1. Compound No.
A photosensitive drum similar to that of Example 8 was prepared except that 6, 7, 8 polycarbonate-based acrylic graft copolymers were used, and the same evaluation as that of Example 1 was performed.

Table 2 shows the results.

Comparative Example 3 A photosensitive drum similar to that of Example 8 was prepared except that a polycarbonate resin having a repeating unit having the following structure was used, and the same evaluation as in Example 1 was performed.

Table 2 shows the results.

[0092]

Embedded image

[0093]

[Table 2]

[0094]

As described above, according to the present invention, the surface layer of an electrophotographic photosensitive member is charged with a polycarbonate resin having a specific structure, whereby the surface of the electrophotographic photosensitive member is contacted and charged. Even when a small-diameter photosensitive drum having a diameter of 30 or less is used at a high-speed rotation by a contact charging method, the amount of shaving is small, and therefore, an electrophotographic apparatus using this electrophotographic photosensitive member can be speeded up, and fog and image density can be reduced. The advantage that no inconvenience such as the above is caused is obtained.

[Brief description of the drawings]

FIG. 1 is a schematic longitudinal sectional view showing an example of an image forming apparatus provided with an electrophotographic photosensitive member of the present invention.

FIG. 2 is a schematic longitudinal sectional view showing another example of an image forming apparatus provided with the electrophotographic photosensitive member of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Electrophotographic photoreceptor 2 Charging means 4 Developing means 5 Transfer means 6 Cleaning means 8 Fixing means 10 Process cartridge

Claims (6)

[Claims] 1. An electrophotographic photoconductor of an electrophotographic apparatus, which is arranged around an electrophotographic photoconductor and is sequentially printed by processes of contact charging, exposure, development, transfer, and fixing,
The surface layer of the photoreceptor has the following general formula (I) [However, in the general formula (I), X represents a hydrogen atom,
A and b represent an integer of 0 to 4; Y represents a single bond, an ether bond, an alkylene group and an alkylidene group having 1 to 5 carbon atoms, and a carbon atom having 5 carbon atoms. -15 cycloalkylene and cycloalkylidene groups, and -S- bond,
Z represents a single bond, a -COO-bond and a -NH-bond, and R ¹ represents a -SO- bond or a -SO ₂ -bond;
Represents a hydrogen atom or a methyl group, n represents an integer of 2 to 40, preferably 3 to 20, l represents 30 to 41, m represents 10 to 500, and k represents an integer of 1 to 10. . R ² is an acrylate side chain, and n represents an integer of 2 to 40. An electrophotographic photoreceptor comprising the polycarbonate-based acrylic graft copolymer represented by the formula: 2. R ² in the side chain acrylate moiety is
The electrophotographic photoreceptor according to claim 1, which is an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group, or an aryl group. 3. The electrophotographic photoreceptor according to claim 1, wherein the content of the acrylate-containing polycarbonate-based graft copolymer is 0.05 to 100% based on the total solid weight of the layer to be added. 4. The electrophotographic photoconductor according to claim 1, wherein the electrophotographic photoconductor has a photosensitive layer on a conductive support, and the conductive support is a cylindrical cylinder having a diameter of 30 mm or less. 5. An electrophotographic apparatus comprising the electrophotographic photoreceptor according to claim 1. 6. The electrophotographic apparatus according to claim 5, wherein the continuous rotation speed of the electrophotographic photosensitive member is 0.25 rotations per second or more.