JP3219492B2 - Electrophotographic photoreceptor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic photosensitive member.

[0002]

2. Description of the Related Art As a conventional electrophotographic photosensitive member, selenium (S) of about 50 μm is formed on a conductive substrate such as aluminum.
e) Some films are formed by a vacuum evaporation method. However, this Se photoconductor has a problem that it has sensitivity only up to a wavelength of about 500 nm. Further, there is a photoconductor in which a Se layer of about 50 μm is formed on a conductive substrate, and a selenium-tellurium (Se—Te) alloy layer of several μm is further formed thereon. The higher the Te content of the Te alloy, the longer the spectral sensitivity extends to longer wavelengths.
As the addition amount of e increases, there is a serious problem in that the surface charge retention characteristics become poor, and in fact, the photoreceptor cannot be used.

A charge generating layer is formed by coating a chlorocyan blue or squarylylate derivative of about 1 μm on an aluminum substrate, and a mixture of a polyvinyl carbazole or pyrazoline derivative having high insulation resistance and a polycarbonate resin is formed thereon. There is also a so-called composite two-layer type photoreceptor in which a charge transport layer is formed by coating to a thickness of 10 to 20 μm, but in reality this photoreceptor has no sensitivity to light of 700 nm or more. .

In recent years, in this composite two-layer type photoreceptor,
The above-mentioned disadvantage has been improved, that is, the semiconductor laser oscillation region 80
Although many photoreceptors having a sensitivity of about 0 nm have been reported, many of them use a phthalocyanine pigment as a charge generating material and have a polyvinyl carbazole film on a charge generating layer having a thickness of about 0.5 to 1 μm. A mixture of a pyrazoline derivative or hydrazone derivative and a polycarbonate resin or polyester resin having a high insulation resistance
A charge transport layer is formed by coating to a thickness of 20 μm to form a composite two-layer type photoreceptor.

Phthalocyanines not only have different absorption spectra and photoconductivity depending on the type of the central metal, but also have different physical properties depending on the crystal type. Several examples have been reported that have been selected for electrophotographic photoreceptors.

[0006] For example, it is reported that titanyl phthalocyanine has various crystal forms, and there is a large difference in chargeability, dark decay, sensitivity, etc. depending on the crystal form.

JP-A-59-49544 discloses that the crystal form of titanyl phthalocyanine includes a Bragg angle (2
θ ± 0.2 degrees) are 9.2 degrees, 13.1 degrees, 20.7 degrees,
Those which give strong diffraction peaks at 26.2 degrees and 27.1 degrees are described as suitable, and the X-ray diffraction spectrum is shown. The electrophotographic properties of a photoreceptor using this crystalline form of titanyl phthalocyanine as a charge generating material are as follows:
Dark decay (DDR): 85%, sensitivity (E1 _{/ 2} ): 0.57 l
ux ・ sec.

In JP-A-59-166959, a deposited film of titanyl phthalocyanine is left in saturated vapor of tetrahydrofuran for 1 to 24 hours to change the crystal form to form a charge generation layer. The X-ray diffraction spectrum has a small number of peaks and a wide width, and has a Bragg angle (2θ) of 7.5 degrees, 12.6 degrees, 13.0 degrees, and 25 degrees.
It has been shown to give strong diffraction peaks at 4, 26.2 and 28.6 degrees. The electrophotographic characteristics of a photoreceptor using this crystalline form of titanyl phthalocyanine as a charge generation material are as follows: dark decay (DDR): 86%, sensitivity (E _1/2 ):
It is 0.7lux · sec.

In JP-A-2-131243, the crystal form of titanyl phthalocyanine has a Bragg angle of 2
Those having a main diffraction peak at 7.3 degrees are described as being suitable. The electrophotographic properties of a photoreceptor using this crystalline form of titanyl phthalocyanine as a charge generating material are as follows:
Dark decay (DDR): 77.2%, sensitivity (E _1/2 ): 0.
It is 38 lux · sec.

As described above, the electrophotographic properties of phthalocyanines greatly differ depending on the crystal form, and the crystal form is an important factor which affects the performance as an electrophotographic photosensitive member.

Japanese Patent Application Laid-Open No. 3-255456 discloses an example using two or more phthalocyanines, and shows an example using a mixture of titanyl phthalocyanine and metal-free phthalocyanine as a charge generating material.

As described above, titanyl phthalocyanine has a very high sensitivity due to the conversion of the crystal form and exhibits excellent characteristics. However, in laser printers and the like,
Higher image quality and higher definition have been developed, and an electrophotographic photoreceptor having higher sensitivity characteristics has been demanded.

The charge transporting material used in the charge transporting layer may be a charge transporting material having an electron transporting ability, such as a mixture of polyvinyl carbazole and trinitrofluorenone (molar ratio 1: 1), hydrazone, enamine, benzidine derivative (particularly, JP-B-55-42380, JP-A-62-2
37458, JP-B-59-9049, JP-A-55-7940, JP-A-61-295558, U.S. Pat. No. 4,265,990, U.S. Pat.
No. 6,008, U.S. Pat. No. 4,588,666) and the like.

[0014] Benzidine derivatives include N, N,
N ', N'-tetraphenylbenzidine, N, N'-diphenyl-N, N'-bis (3-methylphenyl) -benzidine, N, N, N', N'-tetrakis (4-methylphenyl)- Benzidine, N, N'-diphenyl-
N, N'-bis (4-methoxyphenyl) -benzidine and the like are known, and these benzidine derivatives are
There are drawbacks in that it has low solubility in organic solvents and is relatively easily oxidized. That is, it is difficult to prepare a coating solution for forming the charge transport layer due to low solubility in the organic solvent and / or the binder, or crystals of the benzidine derivative are precipitated during the formation of the coating film. There is. Further, even when the charge transport layer can be formed as a good coating film, the oxidation resistance of the benzidine derivative is inferior, so that the chargeability, dark decay, sensitivity, image quality, etc. are deteriorated when used repeatedly. There is.

[0015]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems and provides a high-sensitivity electrophotographic photosensitive member.

[0016]

According to the present invention, there is provided an electrophotographic photosensitive member provided with a photoconductive layer containing a charge generating material and a charge transporting material, wherein the charge generating material has a Bragg angle (2θ) in an X-ray diffraction spectrum of CuKα. (± 0.2 degrees).
5 degrees, 22.5 degrees, 24.3 degrees, 25.3 degrees and 28.
A phthalocyanine composition containing a titanyl phthalocyanine having a main diffraction peak at 6 degrees and a trivalent halogenated metal phthalocyanine as a central metal, and wherein the charge transporting substance is a fluorine-containing N represented by the general formula (I) , N, N ',
The present invention relates to an electrophotographic photoreceptor that is an N′-tetraarylbenzidine derivative.

Embedded image (R ₁ and R ₂ each independently represent a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, an aryl group, a fluoroalkyl group or a fluoroalkoxy group, and at least one of R ₁ and R ₂ is a fluoroalkyl A group or a fluoroalkoxy group, two R ₃ each independently represent a hydrogen atom or an alkyl group, Ar ₁ and Ar ₂ each independently represent an aryl group, and m and n each independently represent Represents an integer of 0 to 5)

Hereinafter, the present invention will be described in detail. The titanyl phthalocyanine used in the present invention can be produced, for example, as follows. Phthalonitrile
4 g (0.144 mol) of α-chloronaphthalene 120
of titanium tetrachloride in a nitrogen atmosphere.
(0.0364 mol) is added dropwise. After dropping, the mixture was reacted at 200 to 220 ° C. for 3 hours while heating and stirring.
Filter hot at 0-130 ° C and wash with α-chloronaphthalene then methanol. Hydrolysis (90 ° C., 1 hour) is performed with 140 ml of ion-exchanged water, and this operation is repeated until the solution becomes neutral, and washed with methanol. Next, the substrate is washed with N-methyl-2-pyrrolidone heated to 100 ° C., and further washed with methanol. The compound thus obtained is dried by heating under vacuum at 60 ° C. to obtain titanyl phthalocyanine (yield 46%).

In the phthalocyanine metal halide compound having a trivalent central metal used in the present invention, examples of the trivalent metal as the central metal include In, Ga, and Al, and examples of the halogen include Cl and Br. Further, the phthalocyanine ring may have a substituent such as halogen. The compound is a known compound. Of these, for example, monohalogen metal phthalocyanine and a method for synthesizing monohalogen metal phthalocyanine are described in Inorganic Chemistry 19 , 313.
1 (1980) and JP-A-59-44054.

The monohalogen metal phthalocyanine can be produced, for example, as follows. 78.2 mmol of phthalonitrile and 15.8 metal trihalides
Millimol was placed in 100 ml of quinoline which had been distilled twice and deoxygenated, heated to reflux for 0.5 to 3 hours, allowed to cool, then cooled to room temperature, and filtered, and the crystals were washed with methanol, toluene, and then acetone. Dry at 60 ° C.

Further, the monohalogen metal halogenphthaloanine can be produced as follows. 156 mmol of phthalonitrile and metal trihalide
5 mmol was mixed and melted at 300 ° C.
Heat for ~ 3 hours to obtain crude monohalogen metal halogen phthalocyanine, which is washed with α-chloronaphthalene using a Soxhlet extractor.

In the present invention, the composition ratio of the phthalocyanine mixture containing titanyl phthalocyanine and a metal halide phthalocyanine whose central metal is a trivalent metal is such that the content of the titanyl phthalocyanine in terms of electrophotographic properties such as chargeability, dark decay, and sensitivity is reduced. The range is preferably from 20 to 95% by weight, more preferably from 50 to 90% by weight, particularly preferably from 65 to 90% by weight.
Most preferably, it is in the range of 5 to 90% by weight.

The phthalocyanine mixture can be made amorphous by an acid paste method. For example, 1 g of the phthalocyanine mixture is dissolved in 50 ml of concentrated sulfuric acid, and the solution is dropped into 1 liter of pure water cooled with ice water to cause reprecipitation. After filtration, the precipitate is washed with pure water until the pH becomes 2 to 5, then washed with methanol, and dried at 60 ° C. to obtain a powder of the phthalocyanine composition. The X-ray diffraction spectrum of the phthalocyanine composition thus obtained is a spectrum showing a wide amorphous state without clear sharp peaks. As a method for forming an amorphous state, there is a method by dry milling in addition to the acid paste method using concentrated sulfuric acid.

The phthalocyanine mixture thus obtained in an amorphous state is subjected to crystal transformation by treating with an organic solvent, whereby the phthalocyanine composition having a specific diffraction peak of the present invention can be obtained. For example, 1 g of a phthalocyanine mixture powder in an amorphous state
With 10 ml of N-methyl-2-pyrrolidone as an organic solvent
And heat and stir (the above powder / solvent (weight ratio) is 1
/ 1 to 1/100). Heating temperature is 50 ° C ~ 200
℃, preferably 80 ℃ ~ 150 ℃, the heating time is 1
Hours to 12 hours, preferably 2 hours to 6 hours. After completion of the heating and stirring, the mixture is filtered, washed with methanol, and dried in vacuum at 60 ° C. to obtain 700 mg of crystals of the phthalocyanine composition of the present invention.

Examples of the organic solvent used in this treatment include alcohols such as methanol, ethanol, isopropanol and butanol, n-hexane, octane, and the like.
Alicyclic hydrocarbons such as cyclohexane, benzene, toluene, aromatic hydrocarbons such as xylene, tetrahydrofuran, dioxane, diethyl ether, ethylene glycol dimethyl ether, ethers such as ethylene glycol diethyl ether, acetate cellosolve, acetone, methyl ethyl ketone, cyclohexanone, Ketones such as isophorone, esters such as methyl acetate and ethyl acetate, dimethyl sulfoxide, dimethylformamide, phenol, cresol, anisole, nitrobenzene,
Acetophenone, benzyl alcohol, pyridine, N-
Non-chlorinated organic solvents such as methyl-2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone, quinoline, picoline, dichloromethane, dichloroethane, trichloroethane, tetrachloroethane, carbon tetrachloride, chloroform,
Chlorine organic solvents such as chloromethyloxirane, chlorobenzene and dichlorobenzene are exemplified.

Of these, ketones and non-chlorine organic solvents are preferred, and among them, N-methyl-2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone, pyridine, methyl ethyl ketone and diethyl ketone are preferred.

In general, a phthalocyanine mixture is a mere physical mixture of phthalocyanine used as a raw material,
The X-ray diffraction pattern of the phthalocyanine mixture consists of a superposition of the peak patterns of the individual phthalocyanines used as raw materials. On the other hand, the phthalocyanine composition of the present invention is a mixture of phthalocyanine used as a raw material at a molecular level, and the X-ray diffraction pattern is the same as the peak pattern of each phthalocyanine used alone as a raw material. Indicates a different pattern.

The electrophotographic photoreceptor according to the present invention has a photoconductive layer provided on a conductive support. In the present invention, the photoconductive layer is a layer containing an organic photoconductive substance, and is composed of a coating of an organic photoconductive substance, a coating containing an organic photoconductive substance and a binder, a charge generation layer and a charge transport layer. There is a mold coating and the like.

As the organic photoconductive substance, the above-mentioned phthalocyanine composition is used as an essential component, and further, known substances can be used in combination. In addition, as the organic photoconductive substance, it is preferable to use an organic pigment and / or a charge transporting substance that generates charges in the phthalocyanine composition. The charge generation layer contains the phthalocyanine composition and / or an organic pigment that generates charges, and the charge transport layer contains a charge transport material.

Examples of the organic pigments that generate electric charges include azoxybenzene, disazo, trisazo, benzimidazole, polycyclic quinone, indigoid, quinacridone, perylene, methine, α-type and β-type. , Γ
Pigments known to generate electric charges such as non-metal type or metal type phthalocyanine having various crystal structures such as type, δ type, ε type and χ type can be used. These pigments are described in, for example, JP-A-47-37543, JP-A-47-37544, and JP-A-47-18543.
JP-A-47-18544, JP-A-48-18544
43942, JP-A-48-70538, JP-A-49-1231, JP-A-49-105536
JP, JP-A-50-75214, JP-A-53-75214
No. 44028, JP-A-54-17732, and the like. Further, τ, τ ′, η and η ′ type metal-free phthalocyanines disclosed in JP-A-58-182640 and European Patent Publication No. 92,255 can be used. In addition to these, any organic application that generates charge carriers by light irradiation can be used.

The charge transporting material is represented by the above general formula (I)
The fluorine-containing N, N, N ', N'-tetraarylbenzidine derivative represented by the following formula is used as an essential component. Other charge transporting substances can be used, and examples of such a polymer include poly-N-vinylcarbazole, halogenated poly-N-vinylcarbazole, polyvinylpyrene, polyvinylindoloquinoxaline, and the like. Polyvinyl benzothiophene, polyvinyl anthracene, polyvinyl acridine, polyvinyl pyrazoline, and the like.
Fluorene, 2,7-dinitro-9-fluorenone, 4
H-indeno (1,2,6) thiophen-4-one;
3,7-dinitro-dibenzothiophene-5-oxide, 1-bromopyrene, 2-phenylpyrene, carbazole, N-ethylcarbazole, 3-phenylcarbazole, 3- (N-methyl-N-phenylhydrazone) methyl-9 -Ethylcarbazole, 2-phenylindole, 2-phenylnaphthalene, oxadiazole, 2,
5-bis (4-diethylaminophenyl) -1,3,4
-Oxadiazole, 1-phenyl-3- (4-diethylaminostyryl) -5- (4-diethylaminostyryl) -5- (4-diethylaminophenyl) pyrazoline, 1-phenyl-3- (p-diethylaminophenyl) pyrazoline , P- (dimethylamino) -stilbene, 2- (4-dipropylaminophenyl) -4- (4
-Dimethylaminophenyl) -5- (2-chlorophenyl) -1,3-oxazole, 2- (4-dimethylaminophenyl) -4- (4-dimethylaminophenyl)-
5- (2-fluorophenyl) -1,3-oxazole, 2- (4-diethylaminophenyl) -4- (4-
Dimethylaminophenyl) -5- (2-fluorophenyl) -1,3-oxazole, 2- (4-dipropylaminophenyl) -4- (4-dimethylaminophenyl)
-5- (2-fluorophenyl) -1,3-oxazole, imidazole, chrysene, tetraphen, acridene, triphenylamine, benzidine, derivatives thereof and the like. Fluorine-containing N, N, represented by the general formula (I)
The N ', N'-tetraarylbenzidine derivative can be produced, for example, as follows. General formula

Embedded image [Wherein, R ₃ has the same meaning as in the above general formula (I), and X represents iodine or bromine] and a halogenated biphenyl derivative represented by the following general formula:

Embedded image [Wherein, R ₁ , R ₂ , Ar ¹ and Ar ² have the same meaning as in the above general formula (I)] and a copper-based catalyst (copper powder, copper oxide, halogen) In the presence of a copper compound such as copper oxide) and a basic compound (a carbonate or hydroxide of an alkali metal such as potassium carbonate, sodium carbonate, potassium hydroxide or sodium hydroxide), a solvent-free or organic solvent (nitrobenzene, Dichlorobenzene, quinoline, N, N-dimethylformamide, N
-Methyl-2-pyrrolidone, sulfolane and the like), and after heating and stirring at 180 to 260 ° C for 5 to 30 hours,
The reaction mixture is dissolved in an organic solvent such as methylene chloride or toluene, insolubles are separated, and the solvent is distilled off. The residue is purified by an alumina column or the like, and recrystallized by hexane, cyclohexane, or the like to obtain a compound represented by the general formula ( The fluorine-containing N, N, N ', N'-tetraarylbenzidine represented by I) can be produced.

The amount of the halogenated biphenyl derivative, the diarylamine compound, the copper-based catalyst and the basic compound may be generally used in a stoichiometric amount, but is preferably based on 1 mol of the halogenated biphenyl derivative. The diarylamine compound may be used in the range of 2 to 3 moles of the copper catalyst in the range of 0.5 to 2 moles and the basic compound in the range of 1 to 2 moles.

In the general formula (I), examples of the alkyl group include a methyl group, an ethyl group, an n-propyl group, an iso-propyl group, an n-butyl group and a tert-butyl group. As the alkoxy group, a methoxy group, an ethoxy group,
Examples thereof include an n-propoxy group and an iso-propoxy group. Examples of the aryl group include a phenyl group, a tolyl group, a biphenyl group, a terphenyl group, a naphthyl group and the like. Examples of the fluoroalkyl group include a trifluoromethyl group, a trifluoroethyl group, and a heptafluoropropyl group. Examples of the fluoroalkoxy group include a trifluoromethoxy group, a 2,3-difluoroethoxy group,
2,2,2-trifluoroethoxy group, 1H, 1H-pentafluoropropoxy group, hexafluoro-iso-propoxy group, 1H, 1H-pentafluorobutoxy group,
2,2,3,4,4,4-hexafluorobutoxy group,
And a fluoroalkoxy group such as a 4,4,4-trifluorobutoxy group.

The fluorine-containing N, N, N ', N'-tetraarylbenzidine derivatives represented by the general formula (I) in the present invention include, for example, the following compounds No. 1 to No. 6 and the like. Can be

Embedded image

Embedded image

The above-mentioned phthalocyanine composition and optionally used organic pigments which generate electric charges (both are the former)
And a charge transport material (hereinafter, the latter) is used as a mixture (in the case of forming a single-layer photoconductive layer), the latter / the former are mixed at a weight ratio of 10/1 to 2/1. Is preferred. At this time, the binder is added to the total amount of these compounds (the former +
It is preferable to use 0 to 500% by weight, especially 30 to 500% by weight, based on the latter). When these binders are used, additives such as a plasticizer, a fluidity-imparting agent, and a pinhole inhibitor can be further added as necessary.

When a composite photoconductive layer comprising a charge generation layer and a charge transport layer is formed, the charge generation layer contains the phthalocyanine composition and, if necessary, an organic pigment which generates a charge. The agent may be contained in an amount of not more than 500% by weight based on the total amount of the phthalocyanine composition and the organic pigment, and the above-mentioned additive may be contained in an amount of not more than 5% by weight based on the total amount of the phthalocyanine composition and the organic pigment. May be added. The charge transport layer contains the above-described charge transport substance, and may further contain a binder at 500% by weight or less based on the charge transport substance. When the charge transporting substance is a low molecular weight compound, it is preferable to contain the binder in an amount of 50% by weight or more based on the compound.

The binders usable in all of the above cases include silicone resins, polyamide resins, polyurethane resins, polyester resins, epoxy resins, polyketone resins, polycarbonate resins, polyacryl resins, polystyrene resins, and styrene-butadiene copolymers. , Polymethyl methacrylate resin, polyvinyl chloride, ethylene-vinyl acetate copolymer, vinyl chloride-vinyl acetate copolymer,
Polyacrylamide resin, polyvinyl carbazole, polyvinyl pyrazoline, polyvinyl pyrene and the like can be mentioned. Further, a thermosetting resin and a photocurable resin which are crosslinked by heat and / or light can also be used.

In any case, there is no particular limitation as long as it is an insulating resin capable of forming a film in a normal state, and a resin which is cured by heat and / or light to form a film. Examples of the plasticizer as the additive include halogenated paraffin, dimethylnaphthalene, dibutyl phthalate, and the like. Examples of the fluidity-imparting agent include Modaflow (manufactured by Monsanto Chemical), Acronal 4F (manufactured by Basff), and the like. Examples of the pinhole inhibitor include benzoin and dimethyl phthalate. These may be appropriately selected and used, and the amounts thereof may be appropriately determined.

In the present invention, the conductive substrate is a conductive material such as paper or plastic film subjected to conductive treatment, a plastic film laminated with a metal foil such as aluminum, or a metal plate.

The electrophotographic photoreceptor of the present invention has a photoconductive layer formed on a conductive substrate. The thickness of the photoconductive layer is preferably 5 to 50 μm. When a composite type of a charge generation layer and a charge transport layer is used as the photoconductive layer, the charge generation layer is preferably 0.001 to 10 μm, particularly preferably 0.2 to 10 μm.
厚 5 μm thick. When the thickness is less than 0.001 μm, it is difficult to form the charge generation layer uniformly, and when the thickness exceeds 10 μm, the electrophotographic characteristics tend to deteriorate. The thickness of the charge transport layer is preferably 5 to 50 μm, particularly preferably 8 to 50 μm.
25 μm. If the thickness is less than 5 μm, the initial potential becomes low, and if it exceeds 50 μm, the sensitivity tends to decrease.

To form the photoconductive substrate on the conductive substrate, a method of depositing an organic photoconductive substance on the conductive substrate,
Uniform organic photoconductive substance and other components as necessary in aromatic solvents such as toluene and xylene, halogenated hydrocarbon solvents such as methylene chloride and carbon tetrachloride, and alcohol solvents such as methanol, ethanol and propanol. Or a method of dissolving or dispersing it on a conductive substrate, followed by drying. As a coating method, a spin coating method, a dipping method, or the like can be adopted. In the case where the charge generation layer and the charge transport layer are formed, the same operation can be performed.In this case, the charge generation layer and the charge transport layer may be either upper layers. It may be soaked.

When the phthalocyanine composition of the present invention is applied by a spin coating method, the number of rotation is 3,000 to 3,000 using a coating solution obtained by dissolving the phthalocyanine composition in a halogenated solvent such as chloroform or toluene or a non-polar solvent.
Spin coating at 7000 rpm is preferred,
When the phthalocyanine composition is applied by a dipping method, the phthalocyanine composition is applied to a coating liquid obtained by dispersing the phthalocyanine composition in a halogen solvent such as methanol, dimethylformamide, chloroform, methylene chloride, 1,2-dichloroethane using a ball mill, ultrasonic waves or the like. It is preferable to immerse the conductive substrate.

The electrophotographic photosensitive member according to the present invention may further have an undercoat layer between the conductive support and the photoconductive layer. It is preferable to use a thermoplastic resin for the undercoat layer. Examples of the thermoplastic resin include polyamide resin, polyurethane resin, polyvinyl butyral resin, melamine resin, casein, phenol resin, epoxy resin, ethylene-vinyl acetate copolymer resin, ethylene-acrylic acid copolymer resin and the like. However, a polyamide resin is preferred. As the polyamide resin, specifically, Resin MF30, Resin F30, Resin EF
30T (trade name of polyamide resin manufactured by Teikoku Chemical Industry Co., Ltd.), M-1276 (trade name of polyamide resin manufactured by Nippon Rilsan Co., Ltd.) and the like.

These resins contained in the undercoat layer may be used alone or in combination of two or more. In the present invention, when the undercoat layer is provided using a polyamide resin, it is preferable to use a thermosetting resin and a curing agent together with the polyamide resin. The combined use of a thermosetting resin and a curing agent improves the solvent resistance of the undercoat layer and the strength of the film. Hard to receive.

As the thermosetting resin, for example, a thermosetting resin such as a melamine resin, a benzoguanamine resin, a polyurethane resin, an epoxy resin, a silicone resin, a polyester resin, an acrylic resin, and a urea resin can be used. There is no particular limitation as long as it is a thermosetting resin that can be formed. These are preferably used in an amount of 300% by weight or less based on the thermoplastic resin.

Examples of the curing agent include carboxylic acids such as trimellitic acid and pyromellitic acid, and oligomers of amides having a carboxylic acid. These are preferably used in an amount of 20% by weight or less based on the thermosetting resin.

As a method for forming the undercoat layer, for example, a thermoplastic resin, a thermosetting resin used as necessary, a curing agent, etc. may be mixed with an alcohol solvent such as methanol, ethanol, isopropanol and methylene chloride, and , 1,
Uniformly dissolved in a mixed solvent of a halogen-based solvent such as 2-trichloroethane, and this is coated on a conductive substrate by a coating method such as a dip coating method, a spray coating method, a roll coating method, an applicator coating method, and a wire bar coating method. Coating and drying.

The thickness of the undercoat layer is 0.01 μm to 5.0.
μm is preferable, and particularly preferably 0.05 μm to 2.0 μm. If it is too thin, a uniform charge generation layer cannot be formed, and black spots and white spots tend to be generated. On the other hand, if the thickness is too large, the accumulation of the residual potential increases, and the print density tends to decrease as the number of prints increases.

The electrophotographic photosensitive member according to the present invention may further have a protective layer on the surface.

In the above electrophotographic photoreceptor, since the photosensitive layer contains the above phthalocyanine composition, not only electric characteristics such as chargeability, dark decay, sensitivity, residual potential, but also after repeated charging and discharging, The resolution of the image (defined as the number of fine lines per 1 mm) is also excellent. Therefore, the electrophotographic photosensitive member is not limited to a laser beam printer,
It is useful as a photoconductor used in an image forming apparatus such as a copying machine or a facsimile.

[0050]

The present invention will be described below in detail with reference to examples.

Example 1 1 g of a phthalocyanine mixture consisting of 0.75 g of titanyl phthalocyanine and 0.25 g of indium chloride phthalocyanine was dissolved in 50 ml of sulfuric acid, and the solution was added dropwise to 1 liter of pure water cooled with ice water to cause reprecipitation. After filtration, the precipitate is adjusted to pH with pure water.
= 2-5, then washed with methanol and dried at 60 ° C. to obtain a powder. 1 g of this powder
The mixture was placed in 10 ml of 3-dimethyl-2-imidazolidinone and stirred with heating (150 ° C., 1 hour). After filtration, washing with methanol and vacuum drying at 60 ° C gave 0.78 g of crystals of the phthalocyanine composition of the present invention. The X-ray diffraction spectrum of this crystal is shown in FIG.

1.5 g of the above phthalocyanine composition, 0.9 g of polyvinyl butyral resin ESLEK BL-S (manufactured by Sekisui Chemical Co., Ltd.), 0.1 g of melamine resin ML351W (manufactured by Hitachi Chemical Co., Ltd.), 49 g of ethyl cellosolve and 49 g of tetrahydrofuran Compounded and dispersed with a ball mill. The obtained dispersion is applied on an aluminum plate (conductive substrate 100 mm x 100 mm x 0.1 mm) by a dipping method,
After drying at 140 ° C. for 1 hour, a charge generation layer having a thickness of 0.5 μm was formed. 1.5 g of the above-mentioned No. 1 charge transporting substance,
A coating solution obtained by blending 1.5 g of polycarbonate resin Iupilon S-3000 (manufactured by Mitsubishi Gas Chemical Company) and 15.5 g of methylene chloride is applied on the above substrate by a dipping method, and dried at 120 ° C. for 1 hour. Thus, a charge transport layer having a thickness of 20 μm was formed. The electrophotographic characteristics of the electrophotographic photoreceptor were measured using an electrostatic copying paper tester (Model SP-42, manufactured by Kawaguchi Electric Co., Ltd.).
8). White light sensitivity E ₁ when exposed to white light having an initial charge Vo (−V) after 10 seconds, a dark decay DDR (%) after 30 seconds, and an illuminance of 2 lux after being charged by a −5 kV corona discharge in the dark. _{/ 2} (lux · sec). The spectral sensitivity was measured by Cynthia 30HC (manufactured by Midoriya Denki).
At an initial surface potential of -700 V, an exposure wavelength of 780 nm, and an exposure time of 50 ms, the amount of irradiation energy required to reduce the surface potential to half in 0.2 seconds after exposure, that is, the spectral sensitivity E _50.
(μJ / cm ² ). The resolution was determined by charging by corona discharge so that the surface potential of the electrophotographic photosensitive member would be -600 V to -700 V.
1-T was used as an original image and exposed at 100 lux.sec, and then developed with a positively charged toner.
The image was transferred to white paper and fixed to obtain a test image, which was evaluated based on the number of fine lines per mm. The toner and the transfer / fixing method used in each test were the same. Immediately after the production of the electrophotographic photoreceptor (initial stage), corona charging (surface potential -1000 V ± 100 V) and static elimination (irradiation with light having a wavelength of 500 nm: exposure amount of about 5 μJ / c)
The resolution after repeating m ² ) 10,000 times was evaluated.

Examples 2 to 4 Crystals were produced in the same manner as in Example 1 except that the composition ratio between titanyl phthalocyanine and indium phthalocyanine was as shown in Table 1.

Comparative Example 1 A crystal was produced in the same manner as in Example 1 except that only the titanyl phthalocyanine was used instead of the phthalocyanine mixture. The X-ray diffraction spectrum of this crystal is shown in FIG.
As shown. Comparative Example 2 Example 1 was repeated except that only indium phthalocyanine chloride was used in place of the phthalocyanine composition.
Crystals were produced according to The X-ray diffraction spectrum of this crystal is shown in FIG. Comparative Example 3 1 g of a phthalocyanine mixture composed of 0.75 g of titanyl phthalocyanine and 0.25 g of indium phthalocyanine was dissolved in 50 ml of sulfuric acid, and the solution was added dropwise to 1 liter of pure water cooled with ice water to cause reprecipitation. After filtration, the precipitate is adjusted to pH with pure water.
= 2-5, then washed with methanol and dried at 60 ° C. to obtain a powder. The X-ray diffraction spectrum of this powder is shown in FIG. The electrophotographic characteristics were measured in Example 1.
It evaluated according to.

Table 1 shows the electrophotographic characteristics of Examples 1 to 4 and Comparative Examples 1, 2, and 3.

[Table 1]

Examples 5 to 8 Crystals were produced in the same manner as in Examples 1 to 4, except that the organic solvent treatment was performed using methyl ethyl ketone instead of N-methyl-2-pyrrolidone. The X-ray diffraction spectrum of this crystal is shown in FIG.

Comparative Examples 4 and 5 Crystals were produced in the same manner as in Comparative Examples 1 and 2, except that the organic solvent treatment was performed using methyl ethyl ketone instead of N-methyl-2-pyrrolidone. The X-ray diffraction spectra of the crystals are shown in FIGS.

Table 2 shows the electrophotographic characteristics of Examples 5 to 8 and Comparative Examples 4 and 5.

[Table 2]

Examples 9 to 12 In Examples 1 to 4, indium phthalocyanine bromide was used in place of indium phthalocyanine chloride, and
A crystal and an electrophotographic photoreceptor using the same were prepared in the same manner as in Examples 1 to 4, except that the charge transport material of No. 2 was used instead of the charge transport material of No. 1 as the charge transport material. did.

Comparative Example 6 An electrophotographic photosensitive member according to Comparative Example 1 except that the charge transporting material of No. 2 was used instead of the charge transporting material of No. 1 in Comparative Example 1. Was manufactured. Comparative Example 7 In Comparative Example 2, indium phthalocyanine bromide was used instead of indium phthalocyanine chloride, and the charge transport material of No. 2 was used instead of the charge transport material of No. 1 as the charge transport material. A crystal and an electrophotographic photoreceptor using the same were produced according to Comparative Example 2 except for the above. Comparative Example 8 A powder was obtained in the same manner as in Comparative Example 3 except that indium phthalocyanine bromide was used instead of indium phthalocyanine chloride, and an electrophotographic photoreceptor was produced using the powder. The X-ray diffraction spectrum of this powder was the same as in FIG.

The electrophotographic characteristics of Examples 9 to 12 and Comparative Examples 6, 7 and 8 are shown in Table 3.

[Table 3]

Examples 13 to 16 In Examples 1 to 4, gallium phthalocyanine chloride was used in place of indium phthalocyanine chloride, and the above-mentioned No. 3 charge-transporting material was used in place of the above-mentioned No. 1 charge-transporting material. Example 1 except that a charge transport material was used
Crystals and electrophotographic photoreceptors using the crystals were manufactured according to the methods described in Nos. 1 to 4.

Comparative Example 9 An electrophotographic photoreceptor was prepared in the same manner as in Comparative Example 1 except that the charge transporting material of No. 3 was used instead of the charge transporting material of No. 1 in Comparative Example 1. Was manufactured. Comparative Example 10 In Comparative Example 2, except that gallium chloride phthalocyanine was used instead of indium phthalocyanine chloride, and that the above-mentioned No. 3 charge transport material was used instead of the above No. 1 charge transport material as the charge transport material. Prepared a crystal and an electrophotographic photosensitive member according to Comparative Example 2. Comparative Example 11 A powder was obtained in the same manner as in Comparative Example 3 except that gallium phthalocyanine was used instead of indium phthalocyanine chloride, and an electrophotographic photoreceptor was manufactured using the powder. The X-ray diffraction spectrum of this powder was the same as in FIG.

Examples 13 to 16 and Comparative Examples 9, 10 and 1
Table 4 shows the electrophotographic characteristics of No. 1.

[Table 4]

Examples 17 to 20 In Examples 1 to 4, aluminum chloride phthalocyanine was used in place of indium phthalocyanine chloride, and 1.5 g of the above No. 1 compound was used as a charge transport material.
A crystal and an electrophotographic photoreceptor using the same were prepared in the same manner as in Examples 1 to 4, except that 1 g of the above-mentioned No. 4 compound was used in place of the above.

Comparative Example 12 Comparative Example 1 was carried out in the same manner as in Comparative Example 1, except that 1 g of the above-mentioned No. 4 charge transport material was used instead of 1.5 g of the above-mentioned No. 1 charge transport material. An electrophotographic photoreceptor was manufactured. Comparative Example 13 In Comparative Example 2, aluminum chloride phthalocyanine was used instead of indium phthalocyanine chloride, and 1.5 g of the above-mentioned No. 1 charge transport material was used as a charge transport material.
A crystal and an electrophotographic photoreceptor using the same were prepared in the same manner as in Comparative Example 2 except that 1 g of the above-mentioned No. 4 charge transporting substance was used instead of. Comparative Example 14 A powder was obtained according to Comparative Example 3 except that aluminum chloride phthalocyanine was used instead of indium phthalocyanine in Comparative Example 3, and an electrophotographic photoreceptor was produced using the same. The X-ray diffraction spectrum of this powder was the same as in FIG.

Table 5 shows the electrophotographic properties of Examples 17 to 20 and Comparative Examples 12, 13 and 14.

[Table 5]

[0068]

The phthalocyanine composition and fluorine-containing N,
An electrophotographic photosensitive member using an N, N ', N'-tetraallylbenzidine derivative has excellent electrophotographic characteristics such as chargeability, dark decay, and sensitivity, and is required to have higher density and higher image quality than before. It can be suitably applied to an electrophotographic process.

[0069]

[Brief description of the drawings]

FIG. 1 is an X-ray diffraction spectrum of a phthalocyanine composition treated with N-methyl-2-pyrrolidone.

FIG. 2 is an X-ray diffraction spectrum of titanyl phthalocyanine treated with N-methyl-2-pyrrolidone.

FIG. 3 is an X-ray diffraction spectrum of indium phthalocyanine chloride treated with N-methyl-2-pyrrolidone.

FIG. 4 is an X-ray diffraction spectrum of a phthalocyanine composition treated with sulfuric acid.

FIG. 5 is an X-ray diffraction spectrum of a phthalocyanine composition treated with methyl ethyl ketone.

FIG. 6 is an X-ray diffraction spectrum of titanyl phthalocyanine treated with methyl ethyl ketone.

FIG. 7 is an X-ray diffraction spectrum of indium phthalocyanine chloride treated with methyl ethyl ketone.

──────────────────────────────────────────────────続 き Continued on the front page (72) Megumi Matsui 4-3-1-1, Higashicho, Hitachi City, Ibaraki Prefecture Inside Hitachi Chemical Co., Ltd. Ibaraki Research Laboratory (72) Inventor Shigeru Hayashida 4-3-1, Higashimachi, Hitachi City, Ibaraki Prefecture No. Hitachi Chemical Co., Ltd. Ibaraki Research Laboratories (56) References JP-A-4-97159 (JP, A) JP-A-3-174543 (JP, A) JP-A-3-50554 (JP, A) 3-50553 (JP, A) JP-A-1-257967 (JP, A) JP-A-1-230055 (JP, A) JP-A-63-198068 (JP, A) JP-A-62-195667 (JP, A A) (58) Field surveyed (Int. Cl. ⁷ , DB name) G03G 5/06

Claims (3)

(57) [Claims] 1. An electrophotographic photoreceptor provided with a photoconductive layer containing a charge generating substance and a charge transporting substance, wherein the charge generating substance has a Bragg angle (2θ ± 0.2 degrees) of 7 in the X-ray diffraction spectrum of CuKα. 2.5 degrees, 22.5 degrees, 24.
A phthalocyanine composition containing titanyl phthalocyanine having main diffraction peaks at 3 degrees, 25.3 degrees and 28.6 degrees, and a metal halide phthalocyanine whose central metal is a trivalent metal; An electrophotographic photosensitive member, which is a fluorine-containing N, N, N ', N'-tetraarylbenzidine derivative represented by the formula (I). Embedded image (R ₁ and R ₂ each independently represent a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, an aryl group, a fluoroalkyl group or a fluoroalkoxy group, and at least one of R ₁ and R ₂ is a fluoroalkyl A group or a fluoroalkoxy group, two R ₃ each independently represent a hydrogen atom or an alkyl group, Ar ₁ and Ar ₂ each independently represent an aryl group, and m and n each independently represent Represents an integer of 0 to 5) 2. The electrophotographic photoreceptor according to claim 1, wherein the charge generating substance and the charge transporting substance are contained in separate layers. 3. The electrophotographic photosensitive member according to claim 1, wherein an undercoat layer is provided between the conductive support and the photoconductive layer.