JPH1195466A - Electrophotographic photoreceptor, process cartridge provided with the photoreceptor and electrophotographic device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrophotographic photoreceptor with a single layer type photosensitive layer excellent in electrostatic chargeability and sensitivity and having high stability of potential characteristics by forming a photosensitive layer contg. at least an electric charge generating material and an org. electron transferring material dispersed in a bonding resin and using a specified compd. as the org. electron transferring material. SOLUTION: A single layer type photosensitive layer contg. at least an electric charge generating material, an org. hole transferring material and an org. electron transferring material dispersed in a bonding resin is formed on an electrically conductive substrate optionally with an undercoat layer in-between to obtain the objective single layer type electrophotographic photoreceptor. The org. electron transferring material is a compd. represented by the formula, wherein R1 and R2 are each H, halogen, alkyl which may have a substituent, aralkyl which may have a substituent, an arom. cyclic group which may have a substituent or the like and R3 and R4 are each halogen, alkyl which may have a substituent, aralkyl which may have a substituent, nitro, cyano or the like.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a single-layer type electrophotographic photoreceptor, a process cartridge having the electrophotographic photoreceptor, and an electrophotographic apparatus.

[0002]

2. Description of the Related Art Conventionally, as a photoconductive material used in an electrophotographic photoreceptor, an inorganic photoreceptor having a photosensitive layer containing selenium, zinc oxide, cadmium or the like as a main component has been widely used. These have some basic characteristics as a photoreceptor, but have problems such as difficulty in film formation, poor plasticity, and high production cost. Furthermore, inorganic photoconductive materials are generally highly toxic, and have great restrictions on production and handling.

On the other hand, a photoreceptor containing an organic photoconductive material as a main component has many advantages, such as compensating the above-mentioned disadvantages of an inorganic photoreceptor, and has been receiving attention in recent years. Has been put to practical use. As such an organic photoreceptor, a charge transfer complex formed from a photoconductive polymer represented by polyvinyl carbazole and a Lewis acid such as 2,4,7-trinitro-9-fluorenone is mainly used. Has been proposed. These organic photoconductive polymers are superior to inorganic photoconductive materials in terms of lightness, film formability, etc., but are superior to inorganic photoconductive materials in sensitivity, durability, safety, etc. It was inferior and was not always satisfactory.

On the other hand, a function-separated type electrophotographic photoreceptor in which the charge generation function and the charge transport function are shared by different substances brings about an improvement in sensitivity and durability, which have been regarded as disadvantages of conventional organic photoreceptors. Was. Such a function-separated type photoreceptor
There is an advantage that the material selection range of the charge generation material and the charge transport material is wide, and an electrophotographic photosensitive member having arbitrary characteristics can be relatively easily produced.

[0005] However, most of these function-separated type photoconductors are stacked type photoconductors in which a charge transport layer is laminated on a charge generation layer in this order, and the photoconductor of this configuration is used in a negative charging process. The reason for adopting such a configuration is that, in the case of a photoreceptor simply formed as a single layer by mixing the materials to be used, the chargeability, sensitivity, fatigue phenomena of the electrostatic characteristics, and the like are often lower than practical levels. On the other hand, in the case of a laminated photoreceptor, these disadvantages are suppressed, and a charge transport layer capable of designing a film having a high mechanical strength and a film thickness can be disposed on the surface so that the photoreceptor can be used in an electrophotographic process. This is because the photoconductor can have sufficient mechanical durability.

Further, organic materials having a sufficient charge mobility even in a high-speed electrophotographic process have been mostly limited to donor compounds having only the property of hole transport so far. In order to suppress the phenomenon as much as possible and to maintain the mechanical strength of the photoreceptor sufficiently in the state of being subjected to the process, the function of charge generation and charge transfer is divided into layers, and the function separation type structure is adopted. This is because a photoreceptor having a laminated structure in which a charge transport layer having a volatile organic material is disposed on the surface has been regarded as the most reasonable. However, such a function-separated type electrophotographic photosensitive member has a new problem.

As one of the problems, in an electrophotographic apparatus using an organic photoreceptor used for negative charging, a large amount of ozone is generated due to the charging, and therefore, the environment is polluted or the photoreceptor is oxidized. There is a risk of deterioration, and in order to prevent this, a system that does not generate ozone, a system that collects ozone in the apparatus, and the like are required, and there is a disadvantage that the process and the system are complicated. In addition, from the viewpoint of the production of the photoreceptor, the cost increases due to several coating steps and accurate control of the film thickness of these layers.

In view of these problems, it is understood that an electrophotographic photoreceptor using an organic material is desirably of a positive charging process and / or of a single-layer type (a type having a single photosensitive layer). Furthermore, if the photoreceptor can be used for the negative charging process as it is or with a slight change, it is possible to provide a photoreceptor having the advantages of being inexpensive and having a high degree of freedom in the use environment.

In order to achieve these, many single-layer type photoconductors have recently been proposed. For example, JP-A-6-123985
JP, JP-A-6-130688, JP-A-6-130688
JP-A-239881 and JP-A-6-123984 propose a photoreceptor in which a charge generating substance, an organic hole transporting substance and an organic electron transporting substance are dispersed in a binder resin. However, the sensitivity of those photoreceptors is not sufficient, the potential fluctuates greatly due to repeated use, the residual potential is high, etc.
There are still many points to be improved, and they have not been satisfactory for practical use.

[0010]

SUMMARY OF THE INVENTION An object of the present invention is to provide an electrophotographic photosensitive member using a single-layer photosensitive layer which is excellent in chargeability and sensitivity and has a stable potential characteristic even when the electrophotographic process is repeated. Is to provide the body. Another object of the present invention is to provide a process cartridge and an electrophotographic apparatus using the electrophotographic photosensitive member.

[0011]

According to the present invention, a single photosensitive layer is provided on a conductive support directly or via an undercoat layer, and the photosensitive layer comprises at least a charge generating substance and an organic hole transporting substance. And a single-layer electrophotographic photosensitive member, wherein the organic electron transporting material is dispersed in a binder resin, and the organic electron transporting material is a compound represented by the following general formula (1). . General formula (1)

Embedded image In the formula, R ₁ and R ₂ represent a hydrogen atom, a halogen atom,
An alkyl group which may have a substituent, an aralkyl group which may have a substituent, an aromatic ring group which may have a substituent,-
(CH = CH) _p -NO ₂ ,-(CH = CH) _q -R ₅
Or -(CH = CH) _p -NO ₂ ,-(CH = CH) _q -R ₅
Or R ₅ and R ₆ represent an aromatic ring group having a nitro group or a heterocyclic group having a nitro group, and R ₇ represents an alkyl group which may have a substituent, an aralkyl which may have a substituent. R ₆ and R ₇ represent a group, an aromatic ring group which may have a substituent or a heterocyclic group which may have a substituent;
Are directly or saturated hydrocarbons, unsaturated hydrocarbons,
R ₃ and R ₄ may be bonded via an oxygen atom, a sulfur atom, or the like to form a ring, and R ₃ and R ₄ may be a halogen atom, an alkyl group which may have a substituent, or an aralkyl group which may have a substituent. Represents an aromatic ring group which may have a substituent, a heterocyclic group which may have a substituent, a nitro group or a cyano group, p and q are any integers of 0, 1, and 2, and r is It is any integer of 0 or 1.

According to the present invention, there is further provided an electrophotographic apparatus wherein the single-layer type electrophotographic photosensitive member of the present invention and at least one means selected from the group consisting of a charging means, a developing means and a cleaning means are integrally supported. It is composed of a process cartridge which is detachable from the main body.

Further, the present invention comprises an electrophotographic apparatus comprising the single-layer type electrophotographic photosensitive member of the present invention, a charging unit, an image exposing unit, a developing unit and a transferring unit.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION The single-layer type electrophotographic photoreceptor of the present invention has excellent chargeability and sensitivity, is suitable for electrophotographic processes from low speed to high speed, and has a spectral sensitivity range depending on the selection of a charge generating substance. It can be controlled, and can be applied to a photoconductor of a page printer using an LED or a laser for writing, from a monochrome or full color copying machine.

What is particularly important in the present invention is that the compound represented by the general formula (1) is used as the organic electron transporting substance. Thereby, the sensitivity of the photoreceptor is improved, and the charging characteristics and the potential stability are improved. In a single-layer type electrophotographic photoreceptor in which a conventional charge generating substance is dispersed in a resin, the charge generating substance also has a charge transporting function, and has a good transportability of both holes and electrons. Because there is no
Due to low sensitivity and low charge transportability, there are drawbacks such as an increase in residual potential and a decrease in charged potential when used repeatedly. To solve these drawbacks, photoreceptors in which a charge generating substance and a hole transporting substance are dispersed in a resin have been proposed. However, in a photoreceptor in which a hole transporting substance is simply added, the hole transporting function is improved. Electron transport is not sufficient because the charge generating substance continues to be responsible, and problems such as high residual potential and low potential stability upon repeated use could not be overcome.

In the present invention, at least a charge generating substance, an organic hole transporting substance and an organic electron transporting substance are dispersed in a binder resin in the photosensitive layer, and the organic electron transporting substance is represented by the general formula (1). By using the compound shown,
This is to solve the above problem. Although the reason why these problems are solved is not completely clear, one reason is that the conjugation of the electron orbital in the molecule of the compound represented by the general formula (1) is widened, so that the electron transporting property is poor. Excellent, and because the energy level of the non-bonding level of the compound represented by the general formula (1) is low, the injection property of electrons from the charge generating substance to the compound represented by the general formula (1) is high. For this reason, it is considered that electrons and holes generated by light absorption in the charge generating substance are easily injected and transported into the compound represented by the general formula (1) and the organic hole transporting substance, respectively. Can be

The single-layer type electrophotographic photosensitive member of the present invention will be described in more detail with reference to the drawings. FIG. 1 shows an example of the single-layer type electrophotographic photoreceptor of the present invention.
B is a photosensitive layer, 1B1 is a charge generating material, and 1B2 is a matrix in which an organic hole transporting material and an organic electron transporting material (compound represented by the general formula (1)) are dispersed in a binder resin. ing.

In the photoreceptor of the present invention, as described above, the compound represented by the general formula (1) is added as an organic electron transporting substance.

Next, typical examples of the compound represented by the formula (1) will be listed. However, it is not limited to these compounds.

[0020]

[Table 1]

[Table 2]

[Table 3]

[Table 4]

[Table 5]

The amount of the organic electron transporting substance (compound represented by the general formula (1)) in the whole photosensitive layer 1B in the present invention is 1 to 50 wt%, preferably 5 to 40 wt%.

The photoreceptor of the present invention contains an organic hole transporting material as an essential component. The role of the organic hole transport material in the photosensitive layer is to move holes generated by the charge generating material in the photosensitive layer. Due to this transport function, holes are not accumulated in the charge generating substance, and the charge generating function of the charge generating substance can be sufficiently exhibited.

The organic hole transporting material used in the present invention includes a compound having a triphenylamine moiety in the molecule, a hydrazone compound, a triphenylmethane compound, a pyrazoline compound, an oxadiazol compound, a carbazole compound, and a styryl compound. , Butadiene-based compounds, polysilane compounds, and polyvinyl carbazole. The proportion of the organic hole transporting material in the photosensitive layer 12 is 15 wt% or more, preferably 20 to
The range is 50 wt%.

The role of the binder resin in the photosensitive layer 1B is not only good dispersion of the charge generating substance and molecular dispersion of the organic electron transporting substance and the organic hole transporting substance, but also the photosensitive layer required in the electrophotographic process. Also bears the mechanical strength of
Therefore, when the composition ratio of the binder resin is low, these various properties are impaired. Therefore, the amount of the binder resin in the photosensitive layer cannot be extremely low. The ratio of the binder resin to the entire photosensitive layer 1B is 30 to 90 wt%, preferably 40 to 70 wt%.

The binder resin used in the present invention is not particularly limited, and a commercially available resin can be used. Examples of resins that can be used as a binder resin for the photosensitive layer include polyester resins, polycarbonate resins, polystyrene resins, acrylic resins, fluororesins, cellulose, polyurethane resins, epoxy resins, and silicone resins.
Resin, alkyd resin, vinyl chloride resin, vinyl chloride
And vinyl acetate copolymer resins.

In the present invention, the charge generating substance is also an essential component in the photosensitive layer. As the charge generating substance that can be used in the present invention, selenium compounds, amorphous silicon,
Cadmium sulfide, particles of inorganic photoconductive substances such as zinc oxide, bisazo pigments, trisazo pigments, phthalocyanine pigments, perylene pigments, quinacridone pigments, indigo pigments,
And polycyclic quinone pigments. The optimal amount of these charge generating substances contained in the photosensitive layer 12 is 0.1 to 40 wt%, preferably 0.3 to 20 wt%.

The photosensitive layer 1B of the present invention has a thickness of 5 to 100 μm.
m, optimally in the range of 7-35 μm.

As the conductive support 1A used in the present invention, a metal plate such as aluminum, nickel, copper, and stainless steel;
Examples include a metal drum or metal foil, a plastic film or glass on which a thin film of tin oxide, copper iodide or the like is deposited or applied.

In the photoreceptor of the present invention, an undercoat layer may be provided between the support and the photosensitive layer for the purpose of improving conductivity and adhesion between the support and the photosensitive layer. As the material of the undercoat layer, in addition to the resins mentioned in the above examples of the binder resin used for the photosensitive layer, a polyamide resin, polyvinyl alcohol,
Casein, polyvinylpyrrolidone and the like can be used. The thickness of the undercoat layer is in the range of 0.01 to 20 μm, and optimally 0.1 to 5 μm.

Further, the photoreceptor of the present invention may be provided with a surface protective layer on the photosensitive layer 1B for the purpose of improving durability and the like.

The photoreceptor of the present invention is prepared by dissolving the above-mentioned materials in an organic solvent or dispersing them by a ball mill, sand mill, ultrasonic wave or the like to prepare a photosensitive layer forming solution, and dipping the solution into a photosensitive layer or using a blade. The photosensitive layer 1B may be formed by coating on the conductive support 1A by a coating method, a spray coating method or the like, followed by drying.

FIG. 2 shows a schematic configuration 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 photoreceptor of the present invention, which is driven to rotate at a predetermined peripheral speed in the direction of an arrow around a flick 2. In the rotation process, the photosensitive member 1 is uniformly charged at a predetermined positive or negative potential on the peripheral surface thereof by the primary charging means 3, and then the image exposure means (such as a slit exposure or a laser beam scanning exposure) is used. (See FIG. 1). Thus, an electrostatic latent image is sequentially formed on the peripheral surface of the photoconductor 1.

The formed electrostatic latent image is then developed.
Is transferred to the transfer material 6 from the paper supply unit (not shown) and fed between the photosensitive member 1 and the transfer means 6 in synchronization with the rotation of the photosensitive member 1. Are sequentially transferred by the transfer means 6. The transfer material 7 having undergone the image transfer is separated from the photoreceptor surface, introduced into the image fixing means 8 and subjected to image fixing, thereby being printed out as a copy (copy) outside the apparatus. The surface of the photoreceptor 1 after the image transfer is cleaned and cleaned by removing the transfer residual toner by the cleaning means 9, and further subjected to a static elimination process by the pre-exposure light 10 from the pre-exposure means (not shown). After that, it is repeatedly used for image formation. When the primary charging means 3 is a contact charging means using a charging roller or the like, pre-exposure is not necessarily required.

In the present invention, a plurality of components such as the photosensitive member 1, the primary charging means 3, the developing means 5 and the cleaning means 9 are integrally connected as a process cartridge. Alternatively, the process cartridge may be configured to be detachable from a 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 means 3, the developing means 5 and the cleaning means 9 is integrally supported together with the photoreceptor 1 to form a cartridge, and the apparatus main body is guided by a guide means such as the rail 12 of the apparatus main body. The process cartridge 11 can be detachably mounted on the cartridge. When the electrophotographic apparatus is a copier or a printer, the image exposure light 4 uses reflected light or transmitted light from the original, or reads the original with a sensor and converts it into a signal. This is light emitted by scanning of the laser beam, driving of the LED array, driving of the liquid crystal shutter array, and the like.

On the other hand, when used as a facsimile printer, the image exposure light 4 becomes exposure light for printing received data. FIG. 2 is a block diagram showing an example of this case. The controller 14 controls the image reading unit 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. 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 decoded by the CPU 20 and sequentially stored in the image memory 19. Is done. When the image of at least one page is stored in the image memory 19, the image of the page is recorded. The CPU 20 reads out the image information of one page from the image memory 19 and sends out the decoded image information of one page to the printer-controller-21. When receiving the image information of one page from the CPU 20, the printer controller 21 controls the printer 22 to record the image information of the page. CPU 20
Is receiving the next page during recording by the printer-22. Thus, reception and recording of an image are performed.

[0036]

【Example】

Example 1 4 g of oxytitanyl phthalocyanine was added to polyvinyl butyral (butyralization degree: 65%, weight average molecular weight: 3500).
0) A dispersion prepared by dispersing 7 g of the compound in 85 g of a cyclohexanone solvent with a sand mill for 48 hours.

5 g of the organic electron transporting substance of the compound example (1)
4 g of organic hole transporting material of the following structural formula (a)

Embedded image And Z-type polycarbonate resin (weight average molecular weight 300
00) A solution prepared by dissolving 9 g in 70 g of chlorobenzene was mixed with 5 g of the dispersion of oxytitanyl phthalocyanine prepared above.
And further dispersed in a ball mill for 1 hour to prepare a coating solution for the photosensitive layer.

Next, a 5% methanol solution of a polyamide resin (trade name: Amilan CM-8000, manufactured by Toray Industries, Inc.) was applied on an aluminum substrate with a Myrbar, and 0.5 μm thick.
The undercoat layer was formed, and the photosensitive layer coating solution prepared above was further applied with a Myrbar, and the film thickness after drying was 16 μm.
Was produced.

The electrophotographic photosensitive member was ± 6 kV using an electrostatic copying paper tester (EPA-8100) manufactured by Kawaguchi Electric Co., Ltd.
Is applied, and the surface potential is positively or negatively charged to irradiate light with a 20 lux light source and a surface potential Vd (V) after initial darkening of the surface potential Va (V) for 3 seconds. Exposure amount E required for potential to attenuate by half
_1/2 (lux · sec) was measured.

After the obtained photosensitive sheet was pasted on an aluminum cylinder, a copying machine NP-606 was used.
0 (manufactured by Canon Inc.) and a surface potential:
After setting such that Vd = + 650 V and the potential after exposure: Vl = + 200 V, copying was repeated 1000 times,
The subsequent surface potential: Vd 'and post-exposure potential: Vl' were measured using a surface voltmeter. Further, the variation in the surface potential after copying 1000 times: ΔVd = Vd−Vd ′ and the variation in the post-exposure potential: ΔVl = Vl−Vl ′ were calculated.
Shown in

Examples 2 to 10 Electrophotographic photosensitive members were prepared in the same manner as in Example 1 except that the organic hole transporting material and the organic electron transporting material used in Example 1 were changed as shown in Table 7. The same evaluation was performed. Table 7 shows the results.

The organic hole transport material used is a compound of the following structural formulas (b) to (i). Structural formula (b)

Embedded image Structural formula (c)

Embedded image Structural formula (d)

Embedded image Structural formula (e)

Embedded image Structural formula (f)

Embedded image Structural formula (g)

Embedded image Structural formula (h)

Embedded image Structural formula (i)

Embedded image

Comparative Example 1 An electrophotographic photosensitive member was prepared under the same conditions as in Example 1 except that the organic electron transporting material was omitted, and the same evaluation was performed. Table 6 shows the results.

Comparative Examples 2 and 3 An electrophotographic photosensitive member was prepared in the same manner as in Example 1 except that the following structural formulas (j) and (k) were used in place of the organic electron transporting material used in Example 1. Then, the same evaluation was performed.
Table 6 shows the results. Structural formula (j)

Embedded image Structural formula (k)

Embedded image

Example 11 Example 1 was repeated except that the oxytitanium phthalocyanine used in Example 1 was replaced with a bisazo pigment having the following structural formula.
An electrophotographic photoreceptor was prepared under the same conditions as described above, and the same evaluation was performed. Table 7 shows the results.

Embedded image

Example 12 The same conditions as in Example 11 were used except that 2.5 g of (b) and 2.5 g of (d) were used instead of the organic hole transporting material (a) used in Example 11. An electrophotographic photoreceptor was prepared and evaluated in the same manner. Table 7 shows the results.

Comparative Example 4 An electrophotographic photosensitive member was prepared under the same conditions as in Example 11 except that the organic electron transporting material was omitted, and the same evaluation was performed. Table 7 shows the results.

Comparative Example 5 An electrophotographic photosensitive member was prepared under the same conditions as in Example 12 except that the organic electron transporting substance was omitted, and the same evaluation was performed. Table 7 shows the results.

Example 13 A protective layer was formed on the photosensitive layer used in Example 1 by the following method.

25 parts of an acrylic monomer having the following structural formula as a binder resin,

Embedded image As a photoinitiator, 2 parts of 2-methylthioxanthone, 50 parts of antimony-containing tin oxide fine particles having an average particle diameter of 0.02 μm (trade name: T-1, manufactured by Mitsubishi Materials Corporation) and 300 parts of toluene are mixed, and mixed with a sand mill for 72 hours. This was dispersed to prepare a coating liquid for a protective layer. This coating solution was formed into a film by spray coating on the same photosensitive layer as in Example 1, dried, and irradiated with ultraviolet light at a light intensity of 800 mW / cm ² for 5 seconds with a high pressure mercury lamp to form a film having a thickness of 3 μm A protective layer was formed, and an electrophotographic photosensitive member was prepared. This electrophotographic photosensitive member was evaluated in the same manner as in Example 1. Table 7 shows the results.

[0051]

[Table 6]

[Table 7]

[0052]

The electrophotographic photoreceptor comprising a single-layer type photosensitive layer according to the present invention is excellent in sensitivity and chargeability, and has extremely stable potential characteristics even when the copying process is repeated. Can be supplied stably.

[Brief description of the drawings]

FIG. 1 is a schematic view of an example of an electrophotographic photosensitive member comprising a single-layer photosensitive layer according to the present invention.

FIG. 2 is a process card having the electrophotographic photosensitive member of the present invention.
The figure which shows the schematic structure of the electrophotographic apparatus which has a bridge.

FIG. 3 is a diagram showing an example of a facsimile block having the electrophotographic photosensitive member of the present invention.

[Explanation of symbols]

Reference Signs List 1A conductive support 1B photosensitive layer 1B1 charge generating substance 1B2 layer in which organic hole transporting substance and organic electron transporting substance are molecularly dispersed in binder resin 1 electrophotographic photoreceptor of the present invention 2 axis 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 Rail 13 Image reading unit 14 Controller 15 Receiving circuit 16 Transmitting circuit 17 Telephone 18 Line 19 Image Memory 20 CPU 21 Printer Controller 22 Printer

Claims (3)

[Claims] A single photosensitive layer is provided on a conductive support directly or through an undercoat layer, and the photosensitive layer is formed by bonding at least a charge generating substance, an organic hole transporting substance and an organic electron transporting substance. A single-layer type electrophotographic photoreceptor, wherein the organic electron transporting substance is a compound represented by the following general formula (1), wherein the organic electron transporting substance is dispersed in a resin for adhesion. General formula (1) In the formula, R ₁ and R ₂ represent a hydrogen atom, a halogen atom,
An alkyl group which may have a substituent, an aralkyl group which may have a substituent, an aromatic ring group which may have a substituent,-
(CH = CH) _p -NO ₂ ,-(CH = CH) _q -R ₅
Or -(CH = CH) _p -NO ₂ ,-(CH = CH) _q -R ₅
Or R ₅ and R ₆ represent an aromatic ring group having a nitro group or a heterocyclic group having a nitro group, and R ₇ represents an alkyl group which may have a substituent, an aralkyl which may have a substituent. R ₆ and R ₇ represent a group, an aromatic ring group which may have a substituent or a heterocyclic group which may have a substituent;
Are directly or saturated hydrocarbons, unsaturated hydrocarbons,
R ₃ and R ₄ may be bonded via an oxygen atom, a sulfur atom, or the like to form a ring, and R ₃ and R ₄ may be a halogen atom, an alkyl group which may have a substituent, or an aralkyl group which may have a substituent. Represents an aromatic ring group which may have a substituent, a heterocyclic group which may have a substituent, a nitro group or a cyano group, p and q are any integers of 0, 1, and 2, and r is It is any integer of 0 or 1. 2. The electrophotographic photosensitive member according to claim 2, and at least one unit selected from the group consisting of a charging unit, a developing unit and a cleaning unit are integrally supported and detachably attached to the main body of the electrophotographic apparatus. A process cartridge characterized by the following. 3. The electrophotographic photoreceptor according to claim 3, and at least one means selected from the group consisting of a charging means, a developing means and a cleaning means are integrally supported, and are detachably attached to an electrophotographic apparatus main body. A process cartridge characterized by the following.