JPH0743920A - Electrophotographic photoreceptor and electrophotographic device having the same - Google Patents

Abstract

PURPOSE:To provide the electrophotographic photoreceptor having an extremely outstanding sensitivity, residual potential, repetitive characteristic and photomemory. CONSTITUTION:The charge generating layer of this electrophotographic photoreceptor having the charge generating layer and charge transfer layer on a conductive substrate contains the disazo pigment expressed by general formula I (where A1 and A2 denote coupler residues having phenolic hydroxyl groups) and the charge transfer layer contains the fluorene compd. expressed by general formula II (where Ar<1> and Ar<2> denote aryl groups or heterocyclic ring groups; R1 and R2 denote alkyl groups, aryl groups, etc.; R3 denotes a halogen atom, alkyl group, etc.). This electrophotographic device has such electrophotographic photoreceptor. As a result, the electrophotographic photoreceptor having the extremely outstanding sensitivity, residual potential, repetitive characteristic and photomemory is obtd.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic photoconductor, and more particularly to a laminated electrophotographic photoconductor and an electrophotographic apparatus having a charge generation layer and a charge transport layer.

[0002]

2. Description of the Related Art Conventionally, as an electrophotographic photosensitive member, an inorganic electrophotographic photosensitive member having a photosensitive layer containing selenium, cadmium sulfide, zinc oxide or the like as a main component has been widely used.

On the other hand, an electrophotographic photoreceptor having a photosensitive layer containing an organic photoconductive compound as a main component has been attracting attention in recent years.

As such an organic photoreceptor, poly-
An electrophotographic photoconductor having a photoconductive polymer represented by N-vinylcarbazole and a photosensitive layer containing as a main component a charge transfer complex formed from the photoconductive polymer and a Lewis acid such as 2,4,7-trinitro-9-fluorenone. The body has already been put to practical use.

However, this electrophotographic photosensitive member is not always satisfactory in sensitivity and durability.

On the other hand, the function-separated type electrophotographic photosensitive member in which the charge generating function and the charge transporting function are shared by separate substances is remarkably excellent in sensitivity and durability, which have been the drawbacks of the conventional organic electrophotographic photosensitive members. Brought improvement.

Such a function-separated type electrophotographic photosensitive member is
The material selection range of each material of the charge generating substance and the charge transporting substance is wide, and it has an advantage that an electrophotographic photoreceptor having arbitrary characteristics can be manufactured relatively easily.

In particular, the electrophotographic photosensitive member is not limited to the copying machine,
In recent years, with the increasing use in laser beam printers, LED printers, etc., the function-separated type is suitable for setting the spectral sensitivity region that matches the emission wavelength of the light source used.

As the charge generating substance, various azo pigments, phthalocyanine pigments, polycyclic quinone pigments, cyanine dyes, squaric acid dyes, pyrylium salt dyes and the like are known.

Among them, azo pigments have been proposed in many structures from the viewpoints of strong light resistance, large charge generation ability, easy material synthesis and the like.

For example, as a disazo pigment similar to the charge generating substance in the present invention, JP-A-56-116040, JP-A-57-182747, and JP-A-58-4.
No. 9952, No. 58-115447, No. 59-72448, and No. 59-15584.
No. 8, JP-A-58-115445, JP-A-SHO-5
It is well known as described in JP-A-8-115446, JP-A-59-7365 and the like.

What is required of the azo pigment used as the charge generating substance here is that (i) it is stable to heat and light, and (ii) if it exhibits charge generating ability in a dispersed state, the dispersion is It is easy and the dispersion does not change over time. (Iii) The charge generation ability does not change with temperature. (Iv) No change in characteristics during repeated use. (V) Effective for light source used. It has a wide spectral sensitivity range, and (vi) the charge transport material is not limited.

It is of practical importance that these requirements are satisfied at a high level.

Although some of the above-mentioned known pigments satisfy some of the above requirements, none of them meet at a high level.

Known examples of the charge transport material include hydrazone compounds, pyrazoline compounds, stilbene compounds, triarylmethane compounds and arylamine compounds.

The requirements for these compounds are:
(I) stable to light and heat, (ii) stable to ozone, NOx, nitric acid, etc. generated by corona discharge, (iii) exhibiting high charge transport ability, (i)
v) It has high compatibility with organic solvents and binders.

Examples of combinations of the above-mentioned known azo pigments and charge-transporting substances are, for example, JP-A-58-18636, JP-A-57-204551, and JP-A-59-4.
4050, JP-A-59-44051, JP-A-59-157644, and JP-A-60-24549.
JP, JP-A-60-24550, JP-A-60-
24551, JP-A-60-24552, etc. are mentioned.

The electrophotographic photosensitive member obtained by the combination of these has many potential defects in image characteristics such as deterioration of the image due to changes in the operating environment although the potential fluctuation is small during repeated use, and the actual It is a problem in use.

Further, the combination of the azo pigment and the styryl compound described in JP-A-2-113258 is less likely to cause image deterioration due to potential fluctuations during repeated use and changes in operating environment (temperature, humidity). However, it was not always satisfactory in terms of sensitivity and photo memory.

[0020]

SUMMARY OF THE INVENTION An object of the present invention is to provide an electrophotographic photosensitive member having a charge generation layer and a charge transport layer, which has a sufficiently high sensitivity characteristic even in a long wavelength region such as a laser diode oscillation wavelength region. To provide an electrophotographic photoreceptor, which has a small photomemory, maintains a stable potential upon repeated use, and exhibits stable potential characteristics and image characteristics irrespective of usage environment (temperature, humidity). To provide a stable electrophotographic photoreceptor against pigments, ozone generated by corona discharge, NOx, nitric acid and the like.

Another object of the present invention is to provide an electrophotographic apparatus having the above electrophotographic photosensitive member.

[0022]

That is, the present invention provides an electrophotographic photosensitive member having a charge generating layer and a charge transporting layer on a conductive support, wherein the charge generating layer is represented by the following general formula [1].

[0023]

[Chemical 3]

(Wherein A ₁ and A ₂ represent coupler residues having the same or different phenolic hydroxyl groups), and the charge transport layer comprises the following general formula [2]:

[0025]

[Chemical 4]

(Wherein Ar ¹ and Ar ² represent an aryl group or a heterocyclic group which may have a substituent, R ₁ and R ₂ represent a hydrogen atom or an aryl group which may have a substituent,
Represents an aralkyl group which may have a substituent or an alkyl group which may have a substituent, and R ₃ represents a hydrogen atom, a halogen atom, a hydroxyl group, an alkyl group which may have a substituent, or a substituent. And an alkoxy group which may be present).

The present invention is also an electrophotographic apparatus having the above electrophotographic photosensitive member.

Preferred examples of the coupler residue having a phenolic hydroxyl group represented by A ₁ and A ₂ in the general formula [1] include compounds represented by the following general formulas [3] to [8]. To be

[0029]

[Chemical 5]

[0030]

[Chemical 6]

X in the general formulas [3], [4], [5] and [6] is a naphthalene ring, an anthracene ring, a carbazole ring or a benzcarbazole which may be condensed with a benzene ring and may have a substituent. It represents a residue necessary for forming a ring, a polycyclic aromatic ring such as a dibenzocarbazole ring, or a heterocycle.

Y in the general formula [8] represents a divalent aromatic hydrocarbon which may have a substituent or a divalent heterocyclic group containing a nitrogen atom in the ring. Specifically, o-phenylene, o-naphthylene, perinaphthylene, 1,2-anthrylene, 3,4-pyrazolediyl, 2,3-pyridinediyl, 4,5-pyridinediyl, 6,7-indazolediyl, 6 And a divalent group such as 7-quinolinediyl.

R ₄ and R _{5 in the} general formulas [3] and [4]
And R ₆ and R ₇ represent a hydrogen atom, an alkyl group which may have a substituent, an aryl group, an aralkyl group or a heterocyclic group, and R ₄ , R ₅ and R ₆ and R ₇ both represent a nitrogen atom. They may combine with each other to form a cyclic amino group containing a nitrogen atom in the ring. R ₈ and R _{9 in the} general formulas [5] and [6]
Represents a hydrogen atom, an alkyl group which may have a substituent, an aryl group, an aralkyl group or a heterocyclic group, R ₁₀ in the general formula [7] represents an alkyl group which may have a substituent,
It represents an aryl group, an aralkyl group or a heterocyclic group.

Examples of the alkyl group represented above include groups such as methyl, ethyl and propyl, examples of the aryl group include groups such as phenyl, naphthyl and anthryl, examples of the aralkyl group include groups such as benzyl and phenethyl, and examples of the heterocyclic group include pyridyl. , Thionyl, thiazoyl, carbazoyl,
Examples thereof include groups such as benzimidazolyl and benzothiazolyl. Examples of the cyclic amino group containing a nitrogen atom in the ring include pyrrole, pyrroline, pyridine, indole, indoline, carbazole, imidazole, pyrazole, pyrazoline, oxazine and phenoxazine.

As the substituent, an alkyl group such as methyl, ethyl and propyl, a halogen atom such as fluorine, chlorine and bromine iodine, an acyl group such as acetyl and benzyl, an alkylamino group such as dimethylamino and diethylamino, and phenylcarbamoyl. Group, nitro group, cyano group, halomethyl group such as trifluoromethyl group, and the like.

Z in the general formulas [3] and [5] represents an oxygen atom or a sulfur atom, and n represents 0 or 1.

In the present invention, in the general formula [2], A ¹
And Ar ² are preferably 4-methylphenyl groups, and R ₁ and R ₂ are preferably methyl groups and ethyl groups.

Pigments using a coupler of the general formula [3], [4], [5] or [6], in which X in the formula is condensed with a benzene ring to form benzcarbazole, It is preferable as a charge generating substance for a semiconductor laser because it extends to the wavelength region or near the near infrared region.

Typical examples of the disazo pigment represented by the general formula [1] and the fluorene compound represented by the general formula [2] are listed below. The disazo pigment represented by the general formula [1] and the general formula [2] The fluorene compound is not limited to these.

[0040]

[Table 1]

[0041]

[Table 2]

[0042]

[Table 3]

[0043]

[Table 4]

[0044]

[Table 5]

[0045]

[Table 6]

[0046]

[Table 7]

[0047]

[Table 8]

[0048]

[Chemical 7]

[0049]

[Chemical 8]

[0050]

[Chemical 9]

[0051]

[Chemical 10]

[0052]

[Chemical 11]

[0053]

[Chemical 12]

[0054]

[Chemical 13]

[0055]

[Chemical 14]

[0056]

[Chemical 15]

[0057]

[Chemical 16]

[0058]

[Chemical 17]

[0059]

[Chemical 18]

[0060]

[Chemical 19]

[0061]

[Chemical 20]

[0062]

[Chemical 21]

[0063]

[Chemical formula 22]

[0064]

[Chemical formula 23]

[0065]

[Chemical formula 24]

Next, the electrophotographic photosensitive member of the present invention will be described in more detail.

The charge generation layer contains the disazo pigment represented by the general formula [1] as much as possible in order to obtain sufficient absorbance, and is a thin film layer such as a thin film layer in order to shorten the range of the generated charge carriers. 5 μm or less, preferably 0.01
It is desirable to use a thin film layer having a thickness of ˜1 μm.

The charge generation layer can be formed by dispersing the disazo pigment represented by the general formula [1] in an appropriate binder and coating it on a conductive support, or by forming a vapor deposition film by a vacuum vapor deposition device. can do.

The binder used when forming for coating can be selected from a wide range of insulating resins, and can also be selected from organic photoconductive polymers such as poly-N-vinylcarbazole, polyvinylanthracene and polyvinylpyrene.

Preferred are polyvinyl butyral, polyvinyl benzal, polyarylate (polycondensation polymer of bisphenol A and phthalic acid, etc.), polycarbonate, polyester, phenoxy resin, polyvinyl acetate, acrylic resin, polyacrylamide, polyamide, polyvinyl pyridine, cellulose. Examples include resin, polyurethane, epoxy resin, casein, polyvinyl alcohol, polyvinylpyrrolidone and the like.

The resin contained in the charge generation layer is 80% by weight.
The following is suitable, preferably 40% by weight or less.

The solvent that dissolves these resins varies depending on the type of resin, and is preferably selected from the type that does not dissolve the charge transport layer or the undercoat layer.

Specifically, alcohols such as methanol, ethanol and isopropanol, ketones such as acetone, methyl ethyl ketone and cyclohexane, N, N
-Amides such as dimethylformamide and N, N-dimethylacetamide, sulfoxides such as dimethylsulfoxide, ethers such as tetrahydrofuran, dioxane and ethylene glycol monomethyl ether, esters such as methyl acetate and ethyl acetate, chloroform,
Aliphatic halogenated hydrocarbons such as methylene chloride, dichloroethylene, carbon tetrachloride and trichloroethylene, or aromatic compounds such as benzene, toluene, xylene, ligroin, chlorobenzene and dichlorobenzene can be used.

As a coating method, a coating method such as a dip coating method, a spray coating method, a spinner coating method, a bead coating method, a Mayer bar coating method, a plate coating method, a roller coating method or a curtain coating method can be adopted.

Drying is preferably performed by drying by touching at room temperature and then drying by heating. The heat-drying is performed in the temperature range of 30 to 200 ° C. for 5 minutes to 2 hours while still or under blowing air.

The charge transport layer is electrically connected to the charge generation layer, and has a function of receiving charge carriers injected from the charge generation layer in the presence of an electric field and transporting these charge carriers to the surface. is doing. At this time, the charge transport layer may be laminated on the charge generating layer or may be laminated thereunder.

The charge transport layer is formed by dissolving the fluorene compound represented by the general formula [2] together with a suitable binder and coating the solution.

Examples of the binder include insulating materials such as acrylic resin, polyarylate, polyester, polycarbonate, polystyrene, acrylonitrile-styrene copolymer, acrylonitrile-butadiene copolymer, polyvinyl butyral, polyvinyl formal, polysulfone, polyacrylamide, polyamide and chlorinated rubber. Resin or poly-N-vinylcarbazole,
Examples thereof include organic photoconductive polymers such as polyvinyl anthracene and polyvinyl pyrene.

Since the charge transport layer has a limit for transporting charge carriers, the film thickness cannot be increased more than necessary. Generally, it is 5 to 35 μm, but a preferable range is 8 to 30 μm.

When forming the charge transport layer by coating,
A suitable method as described above can be adopted.

An electrophotographic photosensitive member having a laminated structure of a charge generation layer and a charge transport layer is provided on a conductive support.

As the conductive support, one having conductivity itself, for example, metal or alloy such as aluminum or aluminum alloy can be used. In addition, aluminum, aluminum alloy, indium oxide, tin oxide, indium oxide can be used. -Plastic having a layer in which a tin oxide alloy or the like is formed by a vacuum deposition method, conductive particles (for example, carbon black, silver particles, etc.) coated on a plastic or the above metal support with a suitable binder. Examples thereof include a support, a conductive support obtained by impregnating plastic or paper with conductive particles, or a plastic having a conductive polymer.

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 is casein, polyvinyl alcohol, nitrocellulose, ethylene-acrylic acid copolymer, polyamide (nylon 6, nylon 66, nylon 610, copolymerized nylon, alkoxymethylated nylon, etc.), polyurethane, gelatin, aluminum oxide, etc. Can be formed by.

The thickness of the undercoat layer is 0.1 to 5 μm, preferably 0.5 to 3 μm.

Further, in order to protect these photosensitive layers from external impact, a thin resin layer or a resin layer in which conductive particles are dispersed may be provided as a protective layer on the surface of the photosensitive layer.

When the disazo pigment represented by the above general formula [1] is used as a charge generating substance, it may be mixed with another charge generating substance depending on the purpose, and a charge transporting substance is also commonly used. The fluorene compound represented by the formula [2] may be used in combination with another charge transporting substance.

The electrophotographic photosensitive member of the present invention can be used in
When used in a laser diode printer, its performance can be fully utilized, and it can also be widely used in electrophotographic application fields such as LED printers, liquid crystal printers, and laser plate making.

FIG. 2 shows a schematic constitutional example of a transfer type electrophotographic apparatus using the electrophotographic photosensitive member of the present invention.

In the figure, 2-1 is a drum type photosensitive member as an image bearing member, which is rotationally driven around the shaft 2-1a in the direction of the arrow at a predetermined peripheral speed. The photoconductor 2-1 is uniformly charged to its peripheral surface by a charging means 2-2 at a predetermined positive or negative potential in the course of its rotation, and then is exposed to an optical image by an image exposing means (not shown) at an exposing section 2-3. Receive exposure L (slit exposure, laser beam operation exposure, etc.). As a result, electrostatic latent images corresponding to the exposed image are sequentially formed on the peripheral surface of the photoconductor.

The electrostatic latent image is then toner-developed by the developing means 2-4, and the developed image is transferred between the photosensitive member 2-1 and the transfer means 2-5 from the paper feeding section (not shown) by the transfer means 2-5. And the transfer material P fed in synchronization with the rotation of the photoconductor 2-1.
Are sequentially transferred to the surface.

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 2-8 to undergo image fixing and printed out as a copy.

After the image transfer, the surface of the photoconductor 2-1 is cleaned by the cleaning means 2-6 to remove the transfer residual toner, and is further discharged by the pre-exposure means 2-7 to repeat the image. Used in forming.

A corona charging device is generally widely used as the uniform charging means 2-2 for the photosensitive member 2-1. Also, as the transfer device 2-5, corona transfer means is generally widely used. The electrophotographic apparatus is configured by integrally combining a plurality of constituent elements such as the photoconductor, the developing unit, and the cleaning unit described above as an apparatus unit, and this unit is configured to be detachable from the apparatus main body. You may.
For example, at least one of a charging unit, a developing unit, and a cleaning unit is integrally supported together with a photoconductor to form a unit, which is a detachable single unit in the apparatus main body.
It may be detachable by using a guide means such as a rail of the apparatus body. 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 optical 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 facsimile printer, the optical image exposure L becomes an exposure for printing the received data. FIG. 3 is a block diagram showing an example of this case.

The controller 3-11 is an image reading section 3-1.
0 and the printer 3-19 are controlled. Controller 3-
The entire 11 is controlled by the CPU 3-17. The read data from the image reading unit is transmitted to the partner station through the transmission circuit 3-13. The data received from the partner station is sent to the printer 3-19 through the receiving circuit 3-12.
Predetermined image data is stored in the image memory. The printer controller 3-18 controls the printer 3-19. 3-14 is a telephone.

The image received from the line 3-15 (image information from the remote terminal connected via the line) is demodulated by the receiving circuit 3-12, and then the CPU 3-17 performs the composite processing of the image information. It is sequentially stored in the image memory 3-16. Then, at least one page of image is stored in the memory 3
When it is stored in -16, the image of that page is recorded.
The CPU 3-17 reads out one page of image information from the memory 3-16 and sends the combined one page of image information to the printer controller 3-18. Upon receiving the image information from the CPU 3-17, the printer controller 3-18 controls the printer 3-19 so as to record the image information of the page.

The CPU 3-17 is the printer 3-.
During recording by 19, the next page is being received.

As described above, the image is received and recorded.

[0101]

EXAMPLES The present invention will be described below with reference to examples. Example 1 An undercoat layer of 0.3 μm of vinyl chloride-maleic anhydride-vinyl acetate copolymer was formed on an aluminum plate.

Next, 5 g of Exemplified Pigment G-7 was added to a solution prepared by dissolving 2 g of bisphenol Z type polycarbonate resin (viscosity average molecular weight of 30,000) in 95 ml of cyclohexanone, and dispersed for 20 hours by a sand mill.

This dispersion was applied on the undercoat layer by Meyer bar coating so that the film thickness after drying was 0.2 μm, and dried to form a charge generation layer.

Next, 5 g of the exemplified fluorene compound T- (3) and 5 g of bisphenol Z type polycarbonate resin (viscosity average molecular weight of 30,000) were dissolved in 70 ml of chlorobenzene, and this was dissolved on the charge generation layer to give a film thickness after drying. Of 20 μm was applied on the Meyer bar and dried to form a charge transport layer.

The obtained photoconductor was attached to a cylinder of a modified machine of a laser beam printer (trade name: LBP-SX, manufactured by Canon) and charged to set the dark potential to -700 (V). The amount of light required to lower the potential of -700 (V) to -100 (V) by irradiating with laser light having a wavelength of 680 nm was measured and used as the sensitivity. 20 more
The potential when irradiated with a light amount of μJ / cm ² is the residual potential V
It was measured as r. The results are shown below.

Sensitivity 0.27 (μJ / cm ² ) Residual potential Vr 5 (−V) Next, using this photoreceptor, humidity 10%, temperature 50 ° C., humidity 50%, temperature 18 ° C. and humidity 80%, temperature In three environments of 35 ° C., a continuous paper passing durability test of 3000 sheets was conducted under the conditions of dark area potential −700 (V) and light area potential −100 (V), respectively, and measurement of the potential of the dark area and light area after the endurance. When the images were evaluated, the same good images as those at the initial stage were obtained after endurance in any environment.

FIG. 1 shows the spectral sensitivity distribution when the maximum spectral sensitivity of the electrophotographic photosensitive member used in Example 1 is 100.

Thus, the electrophotographic photosensitive member of the present invention has 6
It exhibits stable high sensitivity characteristics in a long wavelength region around 60 to 700 nm.

(Examples 2 to 10) An electrophotographic photosensitive member was prepared in the same manner as in Example 1 by combining the exemplified pigment and the exemplified fluorenone compound.

These photoconductors were attached to the cylinder of a laser beam printer (trade name: LBP-SX, manufactured by Canon) as in Example 1, and the dark potential was -7.
Charge is set to 00 (V), and 680 nm
Of the laser beam of -700 (V) to -10
The amount of light EΔ ₆₀₀ required to reduce the voltage to 0 (V) was measured. Further, the potential when irradiated with a light amount of 20 μJ / cm ² was measured as the residual potential Vr.

Further, these photoconductors are set to a dark part potential of -700.
(V) Bright part potential-Reset to -200 (V) and then continuous 5
Durability of 000 sheets was performed, and the fluctuation amounts ΔV _D and ΔV _L of the dark portion potential and the light portion potential at the initial stage and after 5,000 sheets were measured. The results are shown in Table 1.

[0112]

[Table 9]

(Comparative Examples 1 to 6) Instead of the fluorene compounds of Examples 2 to 10, compounds H-1 and H- having the following structures were used.
Comparative photoconductors were prepared and evaluated in the same manner as in Examples 2 to 10 except that 2, H-3, H-4, H-5, and H-6 were used as the charge transport material. The results are shown in Table 2.

[0114]

[Chemical 25]

[0115]

[Chemical formula 26]

[0116]

[Table 10]

(Examples 11 to 13) In Examples 1, 3 and 7.
1500Lux with white fluorescent lamp on the photoconductor
For 5 minutes, and 5 minutes after irradiation, the dark area potential and light
Difference from the previous dark space potential [ΔV _PM] To measure, photo memo
Lee was evaluated.

Comparative Examples 7 and 8 Evaluations were made in the same manner as in Example 11 except that the photoconductors prepared in Comparative Examples 1 and 2 were used.

Table 11 shows the above results.

[0120]

[Table 11]

As is apparent from the results shown in Tables 1 to 3, the photoconductor of the present invention has extremely excellent characteristics in sensitivity, residual potential, repetitive characteristics and photomemory.

[0122]

As described above, according to the present invention, a highly durable electrophotography having high sensitivity in a long wavelength region and stably exhibiting excellent potential characteristics irrespective of repeated use and environmental fluctuations. It is possible to provide a photoconductor, an electrophotographic apparatus using the photoconductor, and a facsimile.

[Brief description of drawings]

FIG. 1 is a distribution chart of spectral sensitivity of an electrophotographic photosensitive member used in Example 1.

FIG. 2 is a schematic configuration diagram of a transfer type electrophotographic apparatus of the present invention.

FIG. 3 is a block diagram of a facsimile using the electrophotographic apparatus as a printer.

Claims (2)

[Claims] 1. An electrophotographic photoreceptor having a charge generation layer and a charge transport layer on a conductive support, wherein the charge generation layer is represented by the following general formula [1]: (Wherein A ₁ and A ₂ represent coupler residues having the same or different phenolic hydroxyl groups), and the charge transport layer contains the disazo pigment represented by the following general formula [2] (In the formula, Ar ¹ and Ar ² represent an aryl group or a heterocyclic group which may have a substituent, and R ₁ and R ₂ represent a hydrogen atom, an alkyl group which may have a substituent, or a substituent. Represents an aralkyl group which may have or an aryl group which may have a substituent, and R ₃ represents a hydrogen atom, a halogen atom, a hydroxyl group, an alkyl group which may have a substituent, or a substituent which may have a substituent. An electrophotographic photosensitive member comprising a fluorene compound represented by (showing a good alkoxy group). 2. An electrophotographic apparatus comprising the electrophotographic photosensitive member according to claim 1.