JPH0545899A - Electrrophotographic sensitive body, electrophotographic device, device unit and facsimile constituted by using this body - Google Patents

Abstract

PURPOSE:To obtain the characteristics excellent in photosensitivity and potential stability at the time of repetitive use by using a specific polyvinyl acetal resin having a fluorine atom or trifluoromethyl group as the binder resin of a photosensitive layer. CONSTITUTION:The resin having the structure expressed by formula I is incorporated into the photosensitive layer of the electrophotographic sensitive body having the photosensitive layer on a conductive base. In the formula I, R1 to R5 are the same as or different from each other and denote a hydrogen atom, fluorine atom and trifluoromethyl group; however there is no case all of the R1 to R5 are simultaneously the hydrogen atoms. The remarkable improvement in the sensitivity, the potential stability at the time of the repetitive use and the decrease of the residual potential ore admitted by using such polyvinyl acetal resin in the photosensitive layer. The conceivable reason thereof lies in that the carrier forming efficiency is improved by the electronic interaction of a charge generating material and the polyvinyl acetal resin having the fluorine atom or trifluoromethyl group being an electron acceptive substituent.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic photoreceptor having a photosensitive layer containing a resin having a specific structure, an electrophotographic apparatus using the same, an apparatus unit and a facsimile.

[0002]

2. Description of the Related Art In recent years, most electrophotographic photoreceptors using an organic photoconductive substance use a charge generating substance having a relatively low molecular weight such as an azo pigment or a phthalocyanine pigment dispersed in an appropriate binder resin. In many cases. Among them, a so-called laminated electrophotographic photosensitive member, in which a photosensitive layer is functionally separated into a charge generating layer containing a charge generating substance and a charge transporting layer containing a charge transporting substance, has a high sensitivity, potential characteristics and durability. Because of its superiority, it is currently the mainstream of organic electrophotographic photoreceptors.

In such an electrophotographic photoreceptor, carrier generation efficiency and carrier transport efficiency of the photosensitive layer, and in the case of a laminated type, carrier injection efficiency from the charge generation layer to the charge transport layer, etc. are important to determine the characteristics of the photoreceptor. It becomes a factor. It is considered that these factors are affected not only by the characteristics of the charge generating substance and the charge transporting material but also by the properties of the binder resin. However, the properties of the conventional binder resin are the binding property and the pigment dispersibility. , Mechanical strength and solvent resistance were relatively emphasized and studied. Japanese Patent Application Laid-Open No. 62-30254 describes that the structure, functional group or molecular weight of a binder resin affects electrophotographic properties such as sensitivity, potential stability and residual potential of a photoreceptor. We recognize the binder resin as a functional resin.

However, with the recent demand for higher image quality and higher durability, electrophotographic photoreceptors having more excellent electrophotographic characteristics have been investigated.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide an electrophotographic photoreceptor having high sensitivity, stable potential characteristics even after repeated use and excellent residual potential characteristics.

Another object of the present invention is to provide an electrophotographic apparatus, an apparatus unit and a facsimile having the above electrophotographic photosensitive member.

[0007]

That is, the present invention provides an electrophotographic photosensitive member having a photosensitive layer on a conductive support, wherein the photosensitive layer is represented by the following formula [I]:

[0008]

[Outside 2] (In the formula, R ₁ , R ₂ , R ₃ , R ₄ and R ₅ are the same or different and represent a hydrogen atom, a fluorine atom and a trifluoromethyl group; provided that all of R _{1 to} R ₅ are hydrogen atoms at the same time. The present invention is an electrophotographic photoreceptor characterized by containing a resin having a structure represented by (1).

The present invention also provides an electrophotographic apparatus, an apparatus unit and a facsimile having the above electrophotographic photosensitive member.

The weight average molecular weight of the polyvinyl acetal resin having the structure represented by the formula [I] used in the present invention is preferably 10,000 to 1,000,000, and particularly preferably 100,000 to 500, It is preferably 000. The degree of acetalization is preferably 50 mol% or more, and particularly preferably 70 to 90 mol%. Further, the saponification degree of polyvinyl alcohol used as a raw material of the polyvinyl acetal resin is preferably 85% or more.

In the present invention, by using the polyvinyl acetal resin having the structure represented by the formula [I] in the photosensitive layer, remarkable sensitivity improvement, potential stability during repeated use and reduction of residual potential are recognized. .. this is,
It is considered that this is due to improvement in carrier generation efficiency due to electronic interaction between the charge generating substance and the polyvinyl acetal resin having a fluorine atom or a trifluoromethyl group as an electron-accepting substituent.

That is, the polyvinyl acetal resin used in the present invention also acts as a kind of electron-accepting substance, promotes dissociation efficiency of carriers by electronic interaction with an organic compound which is a charge generating substance, and recombines carriers. It is considered that the suppression of the is advantageous to the generation of free carriers. Particularly, it is considered that the fluorine atom and the trifluoromethyl group have a very high electronegativity, and the above-mentioned effects are very remarkably exhibited.

The representative examples of the polyvinyl acetal resin used in the present invention will be illustrated below with respect to the acetal structure portion, but it is not limited to these.

[0014]

[Table 1]

[0015]

[Table 2]

Of these, R ₃ is preferably a fluorine atom or a trifluoromethyl group, and particularly R ₃
Is a fluorine atom or a trifluoromethyl group, and R ₁ , R ₂ , R ₄ and R ₅ are preferably hydrogen.

Next, a synthetic example of the polyvinyl acetal resin used in the present invention will be shown.

(Synthesis Example) 60 ml of 1,2-dichloroethane was placed in a flask, and polyvinyl alcohol (polymerization degree 1000, saponification degree 98.5%, manufactured by Kuraray Co., Ltd.) was used.
After adding 5 g and 20 g of p-fluorobenzaldehyde, 0.6 ml of concentrated hydrochloric acid was added dropwise, and the mixture was heated with stirring at a temperature of 40 to 45 ° C. for about 8 hours. After the reaction, sodium hydroxide 0.3
The reaction solution was added dropwise to a solution prepared by dissolving g in 2 l of methanol. The precipitated resin is filtered and 1,2-dichloroethane 1
The resin was dissolved in 00 ml and dropped into 2 l of methanol again to precipitate the resin. The precipitated resin is separated by filtration and dried under reduced pressure. 6.1 g of the polyvinyl acetal resin of 1 was obtained. When the acetalization degree of this resin was measured according to the method described in Japanese Industrial Standard K6728 (polyvinyl butyral test method), the acetalization degree was 81%.

Other polyvinyl acetal resins used in the present invention can be synthesized by the same method as above.

The photosensitive layer of the present invention may be a laminated type in which the charge generating layer containing the charge generating substance and the charge transporting layer containing the charge transporting substance are functionally separated, but the charge generating substance and the charge transporting substance are formed in the same layer. A single layer type may be contained, but a laminated type photosensitive layer is preferable.

In the case of the laminated type, it is preferable that the polyvinyl acetal resin used in the present invention is contained in at least the charge generation layer.

The content of the polyvinyl acetal resin used in the present invention is 1 with respect to the layer containing the resin.
It is preferably from 0 to 90% by weight, and particularly preferably from 20 to
It is preferably 50% by weight.

The polyvinyl acetal resin used in the present invention may be used together with other resins. Examples of other resins include polyvinyl butyral, polyvinyl benzal, polyarylate, polycarbonate, polyester, phenoxy resin, acrylic resin, polyacrylamide, polyamide, polyurethane, polystyrene and acrylonitrile-styrene copolymer resin, or poly-N-vinylcarbazole. And organic photoconductive polymers such as polyvinyl anthracene. Further, in the present invention, a copolymer of the component represented by the formula [I] and the component of the above resin can also be used.

Examples of the charge generating substance used in the present invention include azo pigments such as monoazo, bisazo and trisazo, phthalocyanine pigments such as metal phthalocyanine and metal-free phthalocyanine, indigo pigments such as indigo and thioindigo, and peryleneic anhydride. Compounds, perylene-based pigments such as perylene imides, polycyclic quinone-based pigments such as anthanthrone and pyrenequinone, squarylium dyes, pyrylium, thiopyrylium salts, and triphenylmethane dyes.

The charge-transporting substance includes an electron-transporting substance and a hole-transporting substance, and examples of the electron-transporting substance include 2,
There are electron-accepting substances such as 4,7-trinitrofluorenone, 2,4,5,7-tetranitrofluorenone, chloranil, and tetracyanoquinodimethane, and polymers obtained by polymerizing these electron-accepting substances.

As the hole-transporting substance, polycyclic aromatic compounds such as pyrene and anthracene; carbazole, indole, imidazole, oxazole, thiazole, oxadiazole, oxazole, thiazole, oxadiazole, pyrazole, pyrazoline, thiadiazole, triazole. Heterocyclic compounds such as p-diethylaminobenzaldehyde-N, N-diphenylhydrazone, N, N
Hydrazone compounds such as -diphenylhydrazino-3-methylidene-9-ethylarbazole; α-phenyl-4'-N, N-diphenylaminostilbene, 5-
[4- (di-p-tolylamino) benzylidene] -5H
A styryl compound such as dibenzo [a, d] dicloheptene; a benzidine compound; a triarylmethane compound; triphenylamine or a polymer having a group composed of these compounds in the main chain or side chain (for example, poly-N- Vinylcarbazole, polyvinylanthracene, etc.).

The charge generating layer can be formed by applying a solution prepared by dispersing the above charge generating substance in the above resin in a suitable solvent onto a conductive support and then drying it. The film thickness is preferably 5 μm or less, and particularly preferably 0.01 to 1 μm.

The charge transport layer is laminated on or under the charge generation layer and has a function of receiving carriers from the charge generation layer in the presence of an electric field and transporting the carriers. The charge transporting layer is formed by dissolving the above charge transporting substance in a solvent together with a suitable binder resin as necessary, and coating and drying. The film thickness is preferably 5 to 40 μm, and particularly preferably 15 to 40 μm.
30 μm is preferable.

The single-layer type photosensitive layer can be formed by applying a solution prepared by dispersing and dissolving the above-mentioned charge generating substance and charge transporting substance in the above resin in a resin onto a conductive support and drying. The film thickness is preferably 1 to 40 μm, and particularly preferably 10 to 30 μm.

Solvents used for forming these layers include tetrahydrofuran, ethers such as 1,4-dioxane, ketones such as cyclohexanone and methyl ethyl ketone, esters such as ethyl acetate and butyl acetate, toluene and xylene. , Aromatics such as monochlorobenzene, alcohols such as methanol and ethanol, aliphatic halogenated hydrocarbons such as chloroform and methylene chloride, and amides such as N, N-dimethylformamide.

As the conductive support used in the present invention, for example, aluminum, aluminum alloy, copper, zinc, stainless steel, titanium, nickel, indium, gold or platinum is used. In addition, a support obtained by coating such a metal or alloy on a plastic (for example, polyethylene, polypropylene, polyvinyl chloride and polyethylene terephthalate, acrylic resin, etc.) by vacuum vapor deposition, or conductive particles (for example, carbon black, silver particles, etc.) is used as a suitable binder. A support coated with a resin on a plastic or metal substrate, or a support obtained by impregnating plastic or paper with conductive particles can be used.

Examples of the shape of the support include a sheet shape, a drum shape and a belt shape, but it is preferable that the shape is any shape suitable for the electrophotographic photosensitive member to be applied.

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

The subbing layer can be formed of casein, polyvinyl alcohol, nitrocellulose, polyamide (nylon 6, nylon 66, nylon 610, copolymerized nylon, alkoxymethylated nylon, etc.), polyurethane, aluminum oxide, etc. The thickness is preferably 5 μm or less, and particularly preferably 0.1 to 3 μm.

Further, in the present invention, a resin layer or a resin layer containing conductive particles may be laminated as a protective layer on the photosensitive layer.

The various layers described above can be applied by any application method such as a dipping method, a spray coating method, a spinner coating method, a bead coating method, a blade coating method and a beam coating method.

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.

FIG. 1 shows a schematic structural example of a transfer type electrophotographic apparatus using the electrophotographic photosensitive member of the present invention.

In the figure, reference numeral 1 denotes a drum type photosensitive member as an image bearing member, which is rotationally driven around a shaft 1a in a direction of an arrow at a predetermined peripheral speed. In the course of its rotation, the photosensitive member 1 is uniformly charged with a predetermined positive or negative potential on its peripheral surface by the charging means 2, and then at the exposure section 3 an optical image exposure L (slit exposure Laser beam operation exposure). As a result, electrostatic latent images corresponding to the exposed images are sequentially formed on the peripheral surface of the photoconductor.

The electrostatic latent image is then toner-developed by the developing means 4, and the toner-developed image is rotated by the transfer means 5 between the photoconductor 1 and the transfer means 5 from a paper feeding portion (not shown). And is sequentially transferred onto the surface of the transfer material P that is fed in synchronization with the above.

The transfer material P which has received the image transfer is separated from the surface of the photoconductor and is introduced into the image fixing means 8 where it is subjected to the image fixing and printed out as a copy.

After the image transfer, the surface of the photosensitive member 1 is cleaned by the cleaning means 6 to remove the residual toner after transfer, and is further discharged by the pre-exposure means 7 to be repeatedly used for image formation.

As the uniform charging means 2 for the photoconductor 1, a corona charging device is generally widely used. In addition, the transfer device 5
Corona transfer means are also widely used. The electrophotographic apparatus is configured by integrally combining a plurality of components, such as the above-described photoconductor, developing unit, and cleaning unit, as an apparatus unit, and this unit is configured to be detachable from the apparatus main body. May be. For example, at least one of a charging unit, a developing unit, and a cleaning unit is integrally supported together with a photosensitive member to form a unit, which is a detachable single unit in the main body of the apparatus and a guide unit such as a rail of the main body of the apparatus is used. It may be detachable. At this time, the above device unit may be provided with a charging unit and / or a developing unit.

When the electrophotographic apparatus is used as a copying machine or a printer, the light image exposure L irradiates the photoconductor with reflected light or transmitted light from the original, or the original is read by a sensor and converted into a signal. In accordance with this signal, the laser beam is scanned, the LED array is driven, or the liquid crystal shutter array is driven to irradiate the photoconductor with light.

When used as a printer for a facsimile, the optical image exposure L becomes an exposure for printing the received data. FIG. 2 is a block diagram showing an example of this case.

The controller 11 controls the image reading section 10 and the printer 19. The entire controller 11 is CP
It is controlled by U17. The read data from the image reading unit is transmitted to the partner station through the transmission circuit 13. The data received from the partner station is sent to the printer 19 through the receiving circuit 12. The image memory 16 stores predetermined image data. The printer controller 18 controls the printer 19. 14 is a telephone.

The image received from the line 15 (image information from a remote terminal connected via the line) is demodulated by the receiving circuit 12, and then the CPU 17 performs a composite process of the image information and sequentially stores it in the image memory 16. Is stored. Then, when at least one page of image is stored in the memory 16,
The image of that page is recorded. CPU 17 is a memory 1
The image information of one page is read out from 6 and the combined image information of one page is sent to the printer controller 18. The printer controller 18 is the one from the CPU 17.
When the image information of the page is received, the printer 19 is controlled to record the image information of the page.

The CPU 17 is receiving the next page while the printer 19 is recording.

The image is received and recorded as described above.

The present invention will be described in more detail with reference to the following examples.

[0051]

【Example】

1. On an aluminum plate support, 5 g of methoxymethylated nylon resin (number average molecular weight 32,000) and alcohol-soluble copolymerized nylon resin (number average molecular weight 29,00)
0) A solution of 10 g dissolved in 95 g of methanol was applied with a Meyer bar to form an undercoat layer having a film thickness after drying of 1 μm.

Next, a bisazo pigment having the following structure

[0053]

[Outside 3] Add 5 g to 90 g of cyclohexanone and add 2 with a sand mill.
Dispersed for 0 hours. Further, to this liquid, Exemplified Resin No. 1 polyvinyl acetal resin (weight average molecular weight 160,00
0) A solution prepared by dissolving 2 g of cyclohexanone in 20 g was added and dispersed for another 2 hours.

200 g of methyl ethyl ketone was added to this dispersion.
Is added to dilute, and the film thickness is reduced to 0.1 on the previously formed undercoat layer.
The charge generation layer was formed by coating with a Meyer bar so as to have a thickness of 2 μm and drying.

Next, the following formula

[0056]

[Outside 4] 5 g of the styryl compound represented by and 5 g of a polycarbonate resin (number average molecular weight 55,000) are dissolved in 40 g of monochlorobenzene, and this is coated on the charge generation layer with a Meyer bar and dried to form a 20 μm charge transport layer. By forming, an electrophotographic photosensitive member was obtained.

The electrophotographic photosensitive member thus prepared was negatively charged by a corona discharge of -5 KV using an electrostatic copying machine tester (Model SP-428, manufactured by Kawaguchi Electric Co., Ltd.) to darken for 1 second. After being left in place, the charging characteristics were evaluated by exposing with a light having an illuminance of 10 lux using a halogen lamp. As the charging characteristics, the surface potential V ₀ , the exposure amount (that is, the sensitivity) E _1/2 and the residual potential Vr necessary to attenuate the surface potential after being left in the dark for one second to 1/2 were measured. As a result, V ₀ is -700 V and E _1/2 is 1.2 lu.
Vr was 0 V at x · sec.

2. Instead of the bisazo pigment used in Example 1, the following structural formula

[0059]

[Outside 5] The bisazo pigment represented by No. 1 is used as an example of the binder resin for the charge generation layer, and pigment No. An electrophotographic photosensitive member was produced in the same manner as in Example 1 except that the polyvinyl acetal resin of 7 (weight average molecular weight 170,000) was used, and the charging characteristics were evaluated. As a result, V ₀ was −710V, E _1/2 was 1.3lux · sec, and Vr was 0V.

3. Instead of the bisazo pigment used in Example 1, the following formula

[0061]

[Outside 6] The bisazo pigment represented by the formula (1) is used, tetrahydrofuran is used as the dispersion solvent, a 1: 1 mixed solvent of cyclohexanone and tetrahydrofuran is used as the diluting solvent, and the following formula is used instead of the styryl compound.

[0062]

[Outside 7] An electrophotographic photosensitive member was prepared and evaluated in the same manner as in Example 1 except that the triarylamine represented by 1 was used. As a result, V ₀ is −705 V and E _1/2 is 0.8 lux · se.
In c, Vr was 0V.

4. Instead of the charge generation layer dispersion liquid used in Example 1, 350 g of tetrahydrofuran was added to 10 g of metal-free phthalocyanine, and the resin No. 8
Polyvinyl acetal resin (weight average molecular weight 170,
An electrophotographic photosensitive member was prepared in the same manner as in Example 1 except that a liquid prepared by dissolving 5 g of 000) in 50 g of tetrahydrofuran was added and the dispersion liquid was dispersed in a sand mill for 10 hours. As a result, V ₀ is -670V
And, E _1/2 is 1.8lux · sec and Vr is -30V.
Met.

5. An electrophotographic photoreceptor was prepared in the same manner as in Example 4 except that the metal-free phthalocyanine used in Example 4 was replaced with copper phthalocyanine, and the charging characteristics were evaluated. As a result, V ₀ is -680V and E _1/2 is 5.6l.
Vx was −35 V in ux · sec.

(Comparative Examples 1, 2, 3 and 4) Instead of the polyvinyl acetal resin used in Example 1, the following structural formula was used.

[0066]

[Outside 8] (In the formula, X represents a hydrogen atom, a nitro group, a methyl group and a chlorine atom.) In the same manner as in Example 1 except that a polyvinyl acetal resin (degree of acetalization 75-80%) having a structure represented by Then, an electrophotographic photosensitive member was prepared and the charging characteristics were evaluated. However, Vr was not measured. The results are shown in Table 1.

[0067]

[Table 3]

Comparative Example 5 An electrophotographic photosensitive member was prepared in the same manner as in Example 4 except that the polyvinyl acetal resin used in Comparative Example 2 was used instead of the polyvinyl acetal resin used in Example 4, and the charging characteristics were changed. evaluated. As a result, V ₀ is -680V and E _1/2
Was 2.3lux · sec and Vr was −80V.

6. To 4 g of the bisazo pigment used in Example 1, 90 g of cyclohexanone was added and dispersed by a sand mill for 20 hours. In this dispersion, the exemplified resin No. 1 polyvinyl acetal resin (weight average molecular weight 160,000) 2
A solution prepared by dissolving 0 g in 300 g of tetrahydrofuran was added and shaken for 2 hours. Further, 40 g of the styryl compound used in Example 1 and the exemplified resin No. A solution prepared by dissolving 20 g of the polyvinyl acetal resin of 1 (weight average molecular weight: 160,000) in 200 g of tetrahydrofuran was added and shaken. The coating solution thus prepared is applied onto an aluminum plate support with a Meyer bar and dried to give a film thickness of 20 μm.
The photosensitive layer of was formed to prepare an electrophotographic photoreceptor.

The charging characteristics of this electrophotographic photosensitive member are shown in Example 1.
It evaluated by the method similar to. However, the charging should be positive and V
r was not measured. As a result, V ₀ is 710V and E
_1/2 was 2.0 lux · sec.

7.8. And 9. The electrophotographic photoconductors prepared in Examples 1 to 3 are equipped with a -6.5 kV corona charger, an exposure optical system, a developing device, a transfer charger, a static elimination exposure optical system, and a cylinder of an electrophotographic copying machine equipped with a cleaning unit. Pasted on. The initial dark part potential V _D and the dark part potential _VL are set to −700 V and −200 V, respectively, and 50
The durability characteristics of the photoconductor were evaluated by measuring the variation ΔV _D of the dark potential and the variation ΔV _L of the dark potential after repeated use of 00 times. The results are shown in Table 2. It should be noted that a negative potential fluctuation indicates that the absolute value of the potential has decreased, and a positive value fluctuation indicates that the absolute value of the potential has increased.

[0072]

[Table 4]

(Comparative Examples 6.7 and 8) Comparative Examples 1 to 4
The amount of potential fluctuation during repeated use was measured in the same manner as in Example 7 except that the electrophotographic photosensitive member prepared in 1. was used. The results are shown in Table 3.

[0074]

[Table 5]

10. A photoconductor was prepared by laminating the charge generation layer and the charge transport layer of the electrophotographic photoconductor prepared in Example 3 in the reverse order, and the charging property was evaluated by the same method as in Example 1. However, the charging was positive, and Vr was not measured.
As a result, V ₀ is 700V and E _1/2 is 1.5lux · s.
It was ec.

11. The charge transport layer coating solution used in Example 1 was prepared from 2,4,5-trinitro-9-fluorenone (5 g) and a polycarbonate resin (number average molecular weight 300,000).
An electrophotographic photoreceptor was prepared in the same manner as in Example 1 except that 5 g was dissolved in 50 g of tetrahydrofuran.
The charging characteristics were evaluated. However, the charging was positive, and Vr was not measured. As a result, V ₀ was 690 V and E _1/2 was 2.0 lux · sec.

[0077]

INDUSTRIAL APPLICABILITY As described above, the electrophotographic photosensitive member of the present invention uses the specific polyvinyl acetal resin having a fluorine atom or a trifluoromethyl group as the binder resin for the photosensitive layer, thereby improving sensitivity and repeated use. It is possible to obtain the characteristics excellent in the potential stability of.

[Brief description of drawings]

FIG. 1 is a diagram showing a schematic configuration example of an electrophotographic apparatus 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.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Satomi Omura 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Masato Tanaka 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Within the corporation

Claims (6)

[Claims] 1. An electrophotographic photoreceptor having a photosensitive layer on a conductive support, wherein the photosensitive layer is represented by the following formula [I]: (In the formula, R ₁ , R ₂ , R ₃ , R ₄ and R ₅ are the same or different and represent a hydrogen atom, a fluorine atom and a trifluoromethyl group; provided that all of R _{1 to} R ₅ are hydrogen atoms at the same time. An electrophotographic photoreceptor containing a resin having a structure represented by (1). 2. The electrophotographic photosensitive member according to claim 1, wherein R ₃ is a fluorine atom or a trifluoromethyl group. 3. The electrophotographic photosensitive member according to claim ₂ , wherein R ₃ is a fluorine atom or a trifluoromethyl group, and R ₁ , R ₂ , R ₄ and R ₅ are hydrogen atoms. 4. An electron comprising the electrophotographic photosensitive member according to claim 1, electrostatic latent image forming means, means for developing the formed electrostatic latent image, and means for transferring the developed image to a transfer material. Photographic equipment. 5. An electrophotographic photosensitive member according to claim 1, comprising a charging unit and a cleaning unit, integrally supporting the electrophotographic photosensitive member, the charging unit and the cleaning unit, and detachable from the apparatus main body. Characterized device unit. 6. A facsimile having an electrophotographic apparatus having the electrophotographic photosensitive member according to claim 1 and a receiving unit for receiving image information from a remote terminal.