JPH07191479A - Electrophotographic photoreceptor and process cartridge and electrophotographic device having the same - Google Patents

Abstract

PURPOSE:To obtain an electrophotographic photoreceptor stably having superior potential characteristics even when it is repeatedly used or used under various environments by incorporating a specified disazo pigment into the photosensitive layer of an electrophotographic photoreceptor with the photosensitive layer on the electric conductive substrate. CONSTITUTION:The photosensitive layer of this electrophotographic photoreceptor contains a disazo pigment represented by formula I, wherein each of R1-R8 is H, halogen, alkyl or alkoxy, (n) is a positive integer, each of A1 and A2 is a residue of a coupler having a phenolic hydroxyl group, A, and A, may be different from each other and at least one of them is a residue of a coupler represented by formula II where X1 is a residue required to form a polycyclic arom. ring or hetero ring by condensation with the benzene ring, each of R9 and R10 is H, alkyl, aryl, aralkyl or a heterocyclic group, R9 and R10 may be residues forming a cyclic amino group by bonding to each other and Z1 is O or S.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic photoreceptor, and more particularly to an electrophotographic photoreceptor having a photosensitive layer containing a disazo pigment having a specific structure. The present invention also relates to a process cartridge and an electrophotographic apparatus having the above electrophotographic photosensitive member.

[0002]

2. Description of the Related Art An electrophotographic photosensitive member using an organic photoconductive substance has advantages such as extremely high productivity and relatively low cost, and in addition, a dye or pigment to be used is appropriately selected. By doing so, there is an advantage that the color sensitivity can be freely controlled, and thus extensive studies have been made so far. In particular, the function of stacking a charge generation layer containing a charge generation substance such as an organic photoconductive dye or pigment and a charge transport layer containing a charge transport substance such as a photoconductive polymer or a low molecular weight organic photoconductive substance. With the development of the separation type photoreceptor, the sensitivity and durability, which have been the drawbacks of the conventional organic electrophotographic photoreceptor, have been remarkably improved.

Among the organic photoconductive substances, many azo pigments have excellent photoconductivity, and moreover, compounds having various properties can be obtained relatively easily by combining amine components and coupler components. A large number of compounds have hitherto been disclosed in, for example, JP-A-56-116040, JP-A-61-231052, and JP-A-62-26736.
No. 3, Japanese Patent Laid-Open No. 63-264762, and the like.

[0004]

However, with the recent demand for higher image quality and higher durability, it has higher sensitivity, more excellent electrophotographic characteristics even after repeated use, and further excellent Electrophotographic photoconductors which are also environmentally stable have been studied.

An object of the present invention is to provide an electrophotographic photosensitive member having high sensitivity.

Another object of the present invention is to provide an electrophotographic photosensitive member which has stable and excellent potential characteristics even after repeated use and under various environments.

Another object of the present invention is to provide a process cartridge and an electrophotographic apparatus having the electrophotographic photosensitive member as described above.

That is, the present invention provides an electrophotographic photosensitive member having a photosensitive layer on a conductive support, wherein the photosensitive layer has the following formula (1).

[0009]

[Outside 3] [In the formula, R _{1 to} R ₈ are the same or different and each is a hydrogen atom,
Represents a halogen atom, an alkyl group or an alkoxy group, n
Is a positive integer, A ₁ and A ₂ are the same or different and each represents a coupler residue having a phenolic hydroxyl group, A ₁
And at least one of A ₂ is represented by the following formula (2)

[0010]

[Outside 4] (In the formula, X ₁ represents a residue necessary for forming a polycyclic aromatic ring or a heterocyclic ring by condensing with a benzene ring, and R ₉ and R ₁₀
Are the same or different and represent a hydrogen atom, an alkyl group, an aryl group, an aralkyl group, a heterocyclic group and a residue forming a cyclic amino group by bonding with each other, and Z ₁ represents an oxygen atom or a sulfur atom. ) Is a coupler residue. ] It is an electrophotographic photosensitive member characterized by containing the disazo pigment shown by these.

The present invention also provides a process cartridge and an electrophotographic apparatus having the above electrophotographic photosensitive member.

In the above formula (1), the halogen atom of R _{1 to} R ₈ includes a fluorine atom, a chlorine atom, a bromine atom and an iodine atom, and the alkyl group includes a group such as methyl, ethyl and propyl. Examples of the alkoxy group include groups such as methoxy, ethoxy and propoxy, but in the present invention, it is preferable that R _{1 to} R ₈ are all hydrogen atoms. Also, n is a positive integer,
It is particularly preferably an integer of 1 to 6.

A ₁ and A ₂ represent a coupler residue having a phenolic hydroxyl group. The coupler residue means a coupler residue bonded to an azo group by a coupling reaction between the diazo component and the coupler when a disazo pigment is obtained. It is a group corresponding to a part. In the present invention, A ₁ and A ₂
At least one of them is a coupler residue represented by the formula (2). In formula (2), examples of the polycyclic aromatic ring and heterocyclic ring formed by condensing with the benzene ring of X ₁ include naphthalene ring, anthracene ring, carbazole ring, benzocarbazole ring, dibenzocarbazole ring and the like. In addition, as the alkyl group of R ₉ and R ₁₀ , methyl,
Examples include groups such as ethyl and propyl; examples of aryl groups include groups such as phenyl, naphthyl and anthryl; examples of aralkyl groups include groups such as benzyl and phenethyl; and examples of heterocyclic groups include pyridyl, cenyl,
Examples thereof include groups such as thiazolyl, carbazolyl, benzimidazolyl and benzothiazolyl, and cyclic amino groups such as pyrrolyl, indolyl, indolinyl, carbazolyl,
Examples include groups such as imidazolyl, benzimidazolyl, pyrazolyl, phenothiazinyl and phenoxazinyl.

R _{1 to} R ₁₀ and X ₁ may have a substituent, and as the substituent which may be substituted, an alkyl group such as methyl, ethyl and propyl; alkoxy such as methoxy, ethoxy and propoxy. Group; halogen atom such as fluorine, chlorine, bromine and iodine; acyl group such as acetyl and benzoyl; alkylamino group such as dimethylamino and diethylamino; phenylcarbamoyl group; nitro group;
And a halomethyl group such as trifluoromethyl and the like.

In the present invention, it is preferable that both A ₁ and A ₂ are coupler residues represented by the formula (2), but only one of them is a coupler residue represented by the formula (2). The other may be any coupler residue having a phenolic hydroxyl group, but is preferably a coupler residue represented by the following formulas (3) to (8).

[0016]

[Outside 5]

[0017]

[Outside 6]

X _{2 to} X ₅ in the formulas (3), (6), (7) and (8) are condensed with a benzene ring to form a polycyclic aromatic ring such as naphthalene ring and anthracene ring or a carbazole ring,
The residues necessary for forming a heterocycle such as a benzocarbazole ring and a dibenzocarbazole ring are shown.

Y in the formula (5) represents an arylene group or a divalent heterocyclic group containing a nitrogen atom in the ring. Specifically o
-Phenylene, o-naphthylene, perinaphthylene, 1,
2-anthrylene, 3,4-pyrazoldiyl, 2,3
-Pyridinediyl, 4,5-pyridinediyl, 6,7-
Groups such as indazolediyl and 6,7-quinolinediyl are mentioned.

R ₁₁ , R ₁₂ , and R _{15 in the} formulas (3) and (7)
And R ₁₆ represents a hydrogen atom, an alkyl group, an aryl group, an aralkyl group and a heterocyclic group, and R ₁₁ and R ₁₂ and R ₁₅
And R ₁₆ represent a residue which is bonded to each other to form a cyclic amino group.

R ₁₃ in the formula (4) represents an alkyl group, an aryl group, an aralkyl group or a heterocyclic group.

R ₁₄ in the formula (6) represents a hydrogen atom, an alkyl group, an aryl group, an aralkyl group or a heterocyclic group.

R ₁₇ and R ₁₈ in the formula (8) represent a hydrogen atom, an alkyl group, an aryl group, an aralkyl group, a heterocyclic group and a residue which forms a ring group by being bonded to each other.

The above alkyl group is a group such as methyl, ethyl and propyl, the aryl group is a group such as phenyl, naphthyl and anthryl, the aralkyl group is a group such as benzyl and phenethyl, and the heterocyclic group is pyridyl and thienyl. And groups such as thiazolyl, carbazolyl, benzimidazolyl and benzothiazolyl. Examples of the cyclic amino group include groups such as pyrrolyl, indole, indolinyl, carbazolyl, imidazolyl, benzimidazolyl, pyrazolyl, phenothiazinyl and phenoxysazinyl. Examples of the ring group formed by combining R ₁₇ and R ₁₈ include groups such as fluorenidene, xanthenylidene, antronylidene, and hydroindenylidene.

X _{2 to} X ₅ , Y and R _{11 to} R ₁₈ may have a substituent, and the substituent which may be substituted is an alkyl group such as methyl, ethyl and propyl; methoxy,
Alkoxy groups such as ethoxy and propoxy; halogen atoms such as fluorine, chlorine, bromine and iodine; acyl groups such as acetyl and benzoyl; alkylamino groups such as dimethylamino and diethylamino; phenylcarbamoyl groups;
Examples thereof include a nitro group; a cyano group; and a halomethyl group such as trifluoromethyl.

Z ₂ in the formula (6) represents an oxygen atom or a sulfur atom.

In the present invention, A ₁ and A ₂ are represented by a formula selected from the group consisting of formulas (2), (3), (6), (7) and (8), and X _{1 in} the formula When X ₅ is a coupler residue that forms a benzocarbazole ring by condensing with a benzene ring, the disazo pigment is preferable as a charge generating substance for a semiconductor laser because its sensitivity region extends to the near infrared region. Can be used.

Preferred examples of the disazo pigment represented by the formula (1) are listed below, but the disazo pigment used in the present invention is not limited thereto. In addition, the exemplified pigments first show a basic type, and n, A of the changing part in the basic type
Expressed by showing only ₁ and A ₂ .

[0029]

[Outside 7]

[0030]

[Outside 8]

[0031]

[Outside 9]

[0032]

[Outside 10]

[0033]

[Outside 11]

[0034]

[Outside 12]

[0035]

[Outside 13]

[0036]

[Outside 14]

The disazo pigment represented by the formula (1) is
(A) The corresponding diamine is tetrazotized by a conventional method, and the obtained tetrazonium salt and the corresponding coupler are coupled in an aqueous system in the presence of an alkali, or (b) the tetrazonium salt is borofluoride salt or zinc chloride double salt, etc. After the conversion to the above compound, it can be easily synthesized by coupling with a corresponding coupler in the presence of a base such as sodium acetate, triethylamine and N-methylmorpholine in an organic solvent such as N, N-dimethylformamide or dimethylsulfoxide. In the case of synthesizing a disazo pigment in which A ₁ and A ₂ in the formula (1) are different coupler residues, (a) 1 mol of one coupler is first coupled to 1 mol of the tetrazonium salt described above. , Then the other coupler 1
It can be synthesized by coupling moles, or by mixing (b) two types of couplers in an amount of 1 mole each and coupling with a tetrazonium salt.

Synthesis Example (Synthesis of Pigment Example 1) 150 ml of water and 20 ml of concentrated hydrochloric acid in a 300 ml beaker.
(0.23 mol) and 8.4 g of the following diamine compound
(0.032 mol)

[0039]

[Outside 15] , Cool to 0 ° C, and add 4.6 g of sodium nitrite.
A solution prepared by dissolving (0.067 mol) in 10 ml of water was added dropwise over 10 minutes while maintaining the liquid temperature at 5 ° C. After stirring for 15 minutes, carbon filtration was performed, and a solution of 10.5 g (0.096 mol) of sodium borofluoride in 90 ml of water was dropped into this solution while stirring, and the precipitated borofluoride salt was collected by filtration. After being washed with cold water, washed with acetonitrile, and dried under reduced pressure at room temperature. The yield was 12.4 g, and the yield was 84%.

Next, 500 ml of dimethylformamide was placed in a 1 l beaker, and 14.3 g (0.0
42 mol)

[0041]

[Outside 16] Was dissolved and the liquid temperature was cooled to 5 ° C., 9.2 g (0.02 mol) of the borofluoride salt obtained above was dissolved, and then 5.1 g (0.050 mol) of triethylamine was added dropwise over 5 minutes. did. After stirring for 2 hours, the precipitated pigment was collected by filtration, washed with dimethylformamide 4 times and water 3 times, and then freeze-dried. The yield was 17.0 g, and the yield was 90%.

The photosensitive layer of the electrophotographic photosensitive member of the present invention may be in any known form, but a layer containing the disazo pigment represented by the formula (1) as a charge generating substance is used as a charge generating layer, A functionally separated type photosensitive layer in which a charge transporting layer containing a charge transporting substance is laminated on this layer is particularly preferable.

For the charge generation layer, the disazo pigment of the present invention is vacuum-deposited on a conductive support, or a solution in which the disazo pigment is dispersed in a suitable solvent together with a binder resin is known on the conductive support. It can be formed by applying by a method and drying. The film thickness is preferably 5 μm or less, and particularly preferably 0.1 to 1 μm.

The above-mentioned binder resin is selected from various insulating resins or organic photoconductive polymers, but includes polyvinyl butyral, polyvinyl benzal, polyarylate, polycarbonate, polyester, phenoxy resin, cellulose resin, acrylic resin and polyurethane. Is preferred. These resins may have a substituent, and the substituent is preferably a halogen atom, an alkyl group, an alkoxy group, a nitro group, a trifluoromethyl group, a cyano group or the like. The content of the binder resin is preferably 80% by weight or less, and particularly preferably 40% by weight or less, based on the total weight of the charge generation layer.

The above-mentioned solvent is preferably selected from those which dissolve the above-mentioned resin but do not dissolve the charge transport layer and the undercoat layer described later. Specifically, ethers such as tetrahydrofuran and 1,4-dioxane; ketones such as cyclohexanone and methyl ethyl ketone; amides such as N, N-dimethylformamide; esters such as methyl acetate and ethyl acetate; toluene, xylene and Aromatic hydrocarbon compounds such as monochlorobenzene; alcohols such as methanol, ethanol and 2-propanol; and aliphatic hydrocarbon compounds such as chloroform and methylene chloride.

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

The charge transport material is roughly classified into an electron transport material and a hole transport material. Examples of the electron transport material include 2,
Examples include electron-withdrawing substances such as 4,7-trinitrofluorenone, 2,4,5,7-tetranitrofluorenone, chloranil and tetracyanoquinodimethane, and polymers obtained by polymerizing these electron-withdrawing substances. As the hole-transporting substance, polycyclic aromatic compounds such as pyrene and anthracene;
Heterocyclic compounds such as carbazole type, indole type, imidazole type, oxazole type, thiazole type, oxadiazole type, pyrazole type, pyrazoline type, thiadiazole type and triazole type compounds; p-diethylaminobenzaldehyde-N, N-diphenylhydrazone and N, N-diphenylhydrazino-3-methylidene-9-
Hydrazone compounds such as ethylcarbazole; α-phenyl-4′-N, N-diphenylaminostilbene and 5- [4- (di-p-tolylamino) benzylidene]-
Styryl compounds such as 5H-dibenzo [a, d] cycloheptene; benzidine compounds; triarylmethane compounds; triphenylamine compounds; or resins having groups derived from these compounds in their main chains or side chains. (For example, poly-N-vinylcarbazole and polyvinylanthracene) and the like. In addition to these organic charge transport materials, inorganic materials such as selenium, selenium-tellurium, amorphous silicon and cadmium sulfide can also be used. These charge transport materials may be used alone or in combination of two or more.

When the charge transport material does not have a film forming property, a suitable binder resin can be used. Specifically, acrylic resin, polyarate, polyester,
Polycarbonate, polystyrene, acrylonitrile-
Examples thereof include insulating resins such as styrene copolymer, polyacrylamide, polyamide and chlorinated rubber, and organic photoconductive polymers such as poly-N-vinylcarbazole and polyvinylanthracene.

Another specific example of the present invention is an electrophotographic photoreceptor having a photosensitive layer containing the disazo pigment represented by the formula (1) and the above-mentioned charge transporting substance in the same layer. In this case, poly-N is used as the charge transport material.
A charge transfer complex composed of vinylcarbazole and trinitrofluorenone can be used. This electrophotographic photosensitive member can be prepared by coating a solution in which a disazo pigment and a charge-transporting substance are dispersed and dissolved in a suitable binder resin solution on a conductive support and then drying. The film thickness is preferably 5 to 40 μm, and particularly preferably 15 to 30 μm.

In any of the electrophotographic photoreceptors, two or more kinds of disazo pigments represented by the formula (1) may be combined or used in combination with a known charge generating substance, if necessary.

Examples of the material of the conductive support used in the present invention include aluminum, aluminum alloys, copper,
Zinc, stainless steel, vanadium, molybdenum, chrome,
Examples include titanium, nickel, indium, gold, platinum, and the like. In addition, a support formed of a plastic (for example, polyethylene, polypropylene, polyvinyl chloride, polyethylene terephthalate, acrylic resin, etc.) or conductive particles (for example, carbon black and silver particles) formed by coating such a metal or alloy by a vacuum deposition method is suitable. The above-mentioned plastic, a support coated on a metal or an alloy, or a support obtained by impregnating plastic or paper with conductive particles may be used together with the binder resin.The shape may be a drum shape, a sheet shape or a belt. The shape is the most suitable for the electrophotographic apparatus to which it is 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 thickness of the undercoat layer is preferably 5 μm or less, and particularly preferably 0.1 to 3 μm. Examples of the material of the undercoat layer include casein, polyvinyl alcohol, nitrocellulose, polyamide (nylon 6, nylon 66, nylon 610, copolymerized nylon, alkoxymethylated nylon, etc.), polyurethane, aluminum oxide and the like.

Further, in the present invention, for the purpose of protecting the photosensitive layer from external mechanical and chemical adverse effects, etc., a resin layer as a protective layer or a resin layer containing conductive particles or a charge transporting substance. Can also be provided on the photosensitive layer.

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

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

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

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

The transfer material 7 which has received the image transfer is separated from the surface of the photoconductor and introduced into the image fixing means 8 to undergo the image fixing, and is printed out to the outside of the apparatus as a copy.

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

In the present invention, among the constituent elements such as the electrophotographic photosensitive member 1, the primary charging means 3, the developing means 5 and the cleaning means 9 described above, a plurality of components are integrally combined to form a process cartridge, The process cartridge may be detachably attached to the main body of an electrophotographic apparatus such as a copying machine or a laser beam printer. For example, a process in which at least one of the primary charging unit 3, the developing unit 5, and the cleaning unit 9 is integrally supported together with the photoconductor 1 to form a cartridge, and which can be attached to and detached from the apparatus body by using a guide unit such as a rail 12 of the apparatus body. Cartridge 11
Can be

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

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

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

An image received from the line 18 (image information from a remote terminal connected via the line) is demodulated by the receiving circuit 15, and then the image information is decoded by the CPU 20 and sequentially stored in the image memory 19. Is stored. When the image of at least one page is stored in the image memory 19, the image of that page is recorded. CPU20
Reads one page of image information from the image memory 19 and sends the decoded one page of image information to the printer controller 21. Upon 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. The CPU 20 is receiving the next page during recording by the printer 22.

In this way, the image is received and recorded.

Hereinafter, the present invention will be described in more detail with reference to examples.

[0067]

【Example】

Example 1 A solution prepared by dissolving 5 g of methoxymethylated nylon (number average molecular weight 32,000) and 10 g of alcohol-soluble copolymer nylon (number average molecular weight 29,000) in 95 g of methanol was coated on an aluminum substrate with a wire bar and dried. By doing so, an undercoat layer having a film thickness of 1 μm was formed.

Next, 5 g of Pigment Example 1 was added to 95 g of cyclohexanone, butyral resin (butyralization degree: 63 mol%,
2g of number average degree of polymerization 2,000) was added to the solution,
It was dispersed for 20 hours using a sand mill. This dispersion was applied onto the undercoat layer with a wire bar and dried to form a charge generation layer having a thickness of 0.2 μm.

Next, 5 g of a styryl compound represented by the following formula

[0070]

[Outside 17] And polymethylmethacrylate (number average molecular weight 100,0
A solution of 5 g of 00) dissolved in 40 g of chlorobenzene was applied on the charge generation layer with a wire bar and dried to form a charge transport layer having a thickness of 20 μm.

The obtained electrophotographic photosensitive member was subjected to -5 by using an electrostatic copying paper test device (SP-428, manufactured by Kawaguchi Electric Co., Ltd.).
The charging characteristics were evaluated by negatively charging with a KV corona discharge, holding for 1 second in a dark place, and then exposing with halogen light having an illuminance of 10 lux. As the charging characteristics, the surface potential V ₀ immediately after charging and the surface potential after being left in a dark place for 1 second are 1 /
The exposure dose required to attenuate to 2, that is, the sensitivity (E _1/2 ) was measured. The results are shown in Table 1.

Examples 2 to 10 An electrophotographic photosensitive member was prepared and evaluated in the same manner as in Example 1 except that the disazo pigments shown in Table 1 were used instead of Pigment Example 1. The results are shown in Table 1.

[0073]

[Table 1]

Comparative Examples 1 and 2 An electrophotographic photosensitive member was prepared and evaluated in the same manner as in Example 1 except that the following Comparative Pigment Examples 1 and 2 were used in place of Pigment Example 1. The results are shown in Table 2.

[0075]

[Outside 18]

[0076]

[Table 2]

From these results, it can be seen that each of the electrophotographic photosensitive members of the present invention has sufficient charging ability and excellent sensitivity.

Example 11 An electrophotographic copying machine equipped with the electrophotographic photosensitive member prepared in Example 1 was 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 cleaner. I stuck it on the cylinder.

The initial dark portion potential V _D and the light portion potential _VL are set to around -700 V and -200 V, respectively, and 5,000
The durability was evaluated by repeating the use 0 times and measuring the variation ΔV _D of the dark potential and the variation ΔV _L of the bright potential at the initial stage and after the repeated use. The results are shown in Table 3. still,
A negative symbol in the amount of change in potential indicates that the absolute value of the potential has decreased, and a positive symbol indicates that the absolute value of the potential has increased.

Examples 12 to 15 In place of the electrophotographic photosensitive member prepared in Example 1, Example 3,
Durability was evaluated in the same manner as in Example 11 except that the electrophotographic photoconductors prepared in 5, 8, and 10 were used. The results are shown in Table 3.

[0081]

[Table 3]

Comparative Examples 3 and 4 Example 1 was repeated except that the electrophotographic photosensitive members prepared in Comparative Examples 1 and 2 were used in place of the electrophotographic photosensitive member prepared in Example 1.
Durability was evaluated in the same manner as 1. The results are shown in Table 4.

[0083]

[Table 4]

From the results of Examples 11 to 15 and Comparative Examples 3 and 4, the electrophotographic photosensitive member of the present invention has excellent potential stability.

Example 16 An undercoat layer of polyvinyl alcohol (number average molecular weight: 22,000) having a thickness of 0.5 μm was formed on the aluminum surface of an aluminum vapor-deposited polyethylene terephthalate film.

Onto this undercoat layer, 5 g of Pigment Example 9 was added to a solution of 95 g of cyclohexanone and 2 g of butyral resin (degree of butyralization: 63 mol%, number average degree of polymerization: 2,000) dissolved, and 20 By applying the dispersion liquid dispersed for time and drying, the film thickness becomes 0.20μ.
m charge generating layer was formed.

Then, 5 g of a hydrazone compound represented by the following formula

[0088]

[Outside 19] And polycarbonate (weight average molecular weight 55,000) 5
A solution of 40 g of tetrahydrofuran in 40 g is applied onto the charge generation layer and dried to obtain a film thickness of 20
A μm charge transport layer was formed.

The charging characteristics and durability of the obtained electrophotographic photosensitive member were evaluated in the same manner as in Examples 1 and 11. The results are shown below. _{V 0: -695V, E 1/2:} 2.0lux · sec ΔV D: 0V, Δ L: + 10V

Example 17 An undercoat layer of polyvinyl alcohol (number average molecular weight 22,000) having a thickness of 0.5 μm was formed on the aluminum surface of an aluminum vapor-deposited polyethylene terephthalate film.

On the undercoat layer, a solution prepared by dissolving 5 g of Pigment Example 25 in 95 g of tetrahydrofuran and 2 g of poly-p-fluorovinylbenzal (degree of benzalization of 75 mol% or more, number average molecular weight 90,000) was dissolved. In addition, a dispersion liquid dispersed for 20 hours was applied using a sand mill, and dried to form a charge generation layer having a film thickness of 0.20 μm.

Then, 5 g of a triarylamine compound represented by the following formula

[0093]

[Outside 20] And polycarbonate (weight average molecular weight 55,000) 5
A solution in which 40 g of chlorobenzene was dissolved was applied onto the charge generation layer and dried to form a charge transport layer having a thickness of 20 μm.

The charging characteristics and durability of the obtained electrophotographic photosensitive member were evaluated in the same manner as in Examples 1 and 11. The results are shown below. _{V 0: -690V, E 1/2:} 2.3lux · sec ΔV D: 0V, ΔV L: + 5V

Example 18 Example 17 was repeated except that the charge generating layer and the charge transporting layer in the electrophotographic photosensitive member prepared in Example 17 were formed in the reverse order.
An electrophotographic photoreceptor was prepared and evaluated in the same manner as in. However, the polarity of charging was positive. The results are shown below. V ₀ : +705 V, E _1/2 : 2.6 lux · sec ΔV _D : +5 V, ΔV _L : +10 V

Example 19 A charge generation layer was formed in the same manner as in Example 1.

Next, 5 g of 2,4,7-trinitro-9-fluorenone and polycarbonate (weight average molecular weight 3
A solution of 5 g of 50,000) dissolved in 50 g of tetrahydrofuran was applied on the charge generation layer with a wire bar and dried to form a charge transport layer having a thickness of 18 μm.

The obtained electrophotographic photosensitive member was evaluated in the same manner as in Example 1. However, the polarity of charging was positive. The results are shown below. V ₀ : + 695V, E _1/2 : 2.0lux · sec

Example 20 0.5 g of Pigment Example 11 was added to 9.5 g of cyclohexanone and dispersed for 5 hours with a paint shaker. To this dispersion, a solution prepared by dissolving 5 g of the charge transport material used in Example 1 and 5 g of polycarbonate (weight average molecular weight 80,000) in 40 g of tetrahydrofuran was added and further shaken for 1 hour. The obtained solution was applied onto an aluminum substrate with a wire bar and dried to form a photosensitive layer having a film thickness of 20 μm. The produced electrophotographic photosensitive member was evaluated in the same manner as in Example 1. However, the polarity of charging was positive. The results are shown below. V ₀ : + 700V, E _1/2 : 2.0lux · sec

Example 21 50 g of titanium oxide powder coated with tin oxide containing 10% antimony oxide, resol type phenol resin 25
g, methyl cellosolve 20 g, methanol 5 g and silicone oil (polydimethylsiloxane polyoxyalkylene copolymer, weight average molecular weight 3,000) 0.00
2 g of the dispersion liquid was dispersed for 2 hours with a sand mill using φ1 mm glass beads for 2 hours.
80mm x 360mm) and apply it by dip coating at 140 ° C for 3
By drying for 0 minutes, a conductive layer having a film thickness of 20 μm was formed.

On this conductive layer, 6-66-610-12
Four element type polyamide copolymer (weight average molecular weight 30,0
A solution of 5 g of 00) dissolved in a mixed solvent of 70 g of methanol and 25 g of butanol was applied by dip coating and dried to form an undercoat layer having a film thickness of 1 μm.

Next, a dispersion liquid similar to the dispersion liquid for the charge generation layer used in Example 10 was dip-coated on the undercoat layer and dried to form a charge generation layer having a thickness of 0.3 μm. Formed.

Then, 10 g of a triarylamine compound represented by the following formula:

[0104]

[Outside 21] And polycarbonate (weight average molecular weight 20,000) 1
A solution prepared by dissolving 0 g of chlorobenzene in 60 parts was applied onto the charge generation layer by dip coating, and dried at 120 ° C. for 1 hour to form a charge transport layer having a thickness of 20 μm.

The obtained electrophotographic photosensitive member was mounted on a laser beam printer (LBP-SX, manufactured by Canon Inc.), the dark potential was set to -700 V, and the light potential was -1.
The sensitivity was evaluated by measuring the amount of laser light required to reach 50 V (wavelength of laser light: 802 nm). Furthermore, the initial dark area potential and light area potential are each -70.
0V and -150V are set, 5,000 continuous images are output, and the amount of change in dark area potential before and after image output (ΔV
_The durability was evaluated by measuring the fluctuation amount (ΔV _L ) of _D ) and the bright part potential. The results are shown below. The sign of the fluctuation amount of the potential has the same meaning as in Example 11. Sensitivity: 0.25 μJ / cm ² , ΔV _D : 0 V, ΔV _L :
+ 5V

[0106]

As described above, according to the present invention, an electrophotographic photosensitive member having a high sensitivity and having stable and excellent potential characteristics even when it is repeatedly used or used in various environments. A body, a process cartridge having the electrophotographic photosensitive member, and an electrophotographic apparatus can be provided.

[Brief description of drawings]

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

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

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 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 section 14 Controller 15 Receiver circuit 16 Transmitter circuit 17 Telephone 18 Line 19 Image memory 20 CPU 21 Printer controller 22 Printer

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor ▲ Country ▼ Mitsuhiro Eda 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc.

Claims (8)

[Claims] 1. An electrophotographic photosensitive member having a photosensitive layer on a conductive support, wherein the photosensitive layer has the following formula (1): [In the formula, R _{1 to} R ₈ are the same or different and each is a hydrogen atom,
Represents a halogen atom, an alkyl group or an alkoxy group, n
Is a positive integer, A ₁ and A ₂ are the same or different and each represents a coupler residue having a phenolic hydroxyl group, A ₁
At least one of A ₂ and A ₂ is represented by the following formula (2): (In the formula, X ₁ represents a residue necessary for forming a polycyclic aromatic ring or a heterocyclic ring by condensing with a benzene ring, and R ₉ and R ₁₀
Are the same or different and represent a hydrogen atom, an alkyl group, an aryl group, an aralkyl group, a heterocyclic group and a residue forming a cyclic amino group by bonding with each other, and Z ₁ represents an oxygen atom or a sulfur atom. ) Is a coupler residue. ] The electrophotographic photoreceptor containing the disazo pigment shown by these. 2. The electrophotographic photosensitive member according to claim _1, wherein R _{1 to} R ₈ are hydrogen atoms. 3. The electrophotographic photosensitive member according to claim 1, wherein the n is 1 to 6. 4. The electrophotographic photosensitive member according to claim 1, wherein both A ₁ and A ₂ are a coupler residue represented by the formula (2). 5. The electrophotographic photosensitive member according to claim 1, wherein X ₁ is a residue necessary for condensing with a benzene ring to form a benzocarbazole ring. 6. The photosensitive layer has a charge generating layer containing the disazo pigment as a charge generating substance and a charge transporting layer, and the electrophotographic photosensitive member has the charge generating layer on a conductive support, The electrophotographic photoreceptor according to claim 1, further comprising the charge transport layer on the charge generation layer. 7. An electrophotographic photosensitive member according to claim 1, and at least one unit selected from the group consisting of a charging unit, a developing unit and a cleaning unit, which are integrally supported and detachable from the main body of the electrophotographic apparatus. Process cartridge characterized by. 8. An electrophotographic apparatus comprising the electrophotographic photosensitive member according to claim 1, a charging unit, an image exposing unit, a developing unit, and a transferring unit.