JPH09319109A - Electrophotographic photoreceptor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve solubility to a solvent and compatibility with a resin binder used and to improve the stability of electrophotographic characteristics at the time of repetitive use by incorporating a specified butadiene compd. into a photosensitive layer. SOLUTION: This electrophotographic photoreceptor has a photosensitive layer contg. a butadiene ccmpd. represented by the formula, wherein each of Ar1 and Ar2 is phenyl which may be substd. by a substituent selected from among alkyl, alkoxy, dialkylamino, halogen and diphenylamino which may have a substituent and Ar3 is phenyl which may be substd. by a substituent selected from among alkyl, alkoxy, dialkylamino, halogen and dibenzylamino which may have a substituent, pyrenyl, N-alkylcarbazole, N-alkylphenoxazinyl, dibenzothiophenyl, N-alkylphenothiazinyl or dibenzofuranyl.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an electrophotographic photoreceptor having a photosensitive layer containing a butadiene compound useful as a photoconductive material.

[0002]

2. Description of the Related Art JP-A-6-312961 and JP-A-7-173112 propose electrophotographic photoreceptors having a photosensitive layer containing a butadiene compound having two butadiene structures in one molecule. There is. However, these compounds have poor solubility in a solvent and low compatibility with a binder resin used when preparing an electrophotographic photoreceptor, and thus have a problem in film-forming property of a photosensitive layer, or a photosensitive layer. It has the drawback that cracks easily occur.

Further, in JP-A-62-287257 and JP-A-63-314554, 1, 1, 4,
An electrophotographic photoreceptor having a photosensitive layer containing a 4-tetraaryl-1,3-butadiene compound has been proposed.
However, these electrophotographic photosensitive members have a drawback that the characteristics change greatly due to deterioration during repeated use.

In addition, JP-A-60-98437 and JP-A-6-102685 disclose electrophotographic photoreceptors having a photosensitive layer containing a butadiene compound, and JP-A-8-44096 discloses styryl. Electrophotographic photoreceptors each having a photosensitive layer containing a compound have been proposed, but any one of sensitivity, stability during repeated use, solubility in a solvent or compatibility with a binder resin used. It has a problem that it is inferior.

[0005]

The problem to be solved by the present invention is to provide a photoconductive material having good solubility in a solvent and excellent compatibility with a binder resin to be used. It is an object of the present invention to provide an electrophotographic photoreceptor having the above-mentioned organic compound-based electrophotographic photoreceptor with improved defects, sufficient sensitivity for practical use, and stability during repeated use.

[0006]

Means for Solving the Problems As a result of intensive studies to solve the above problems, the present inventors have found that the 1-position,
A butadiene compound having a phenyl group which may each independently have a substituent at each of the 2-position and the 4-position, or has a phenyl group at the 1-position and the 2-position,
And, a butadiene compound having an aromatic heterocycle at the 4-position has good solubility in a solvent, excellent compatibility with a binder resin, and an electrophotographic photoreceptor having a photosensitive layer containing these compounds, The inventors have found that the present invention has high sensitivity and is stable even when repeatedly used, and completed the present invention.

That is, in order to solve the above problems, the present invention provides an electrophotographic photosensitive member having a photosensitive layer on a conductive support, wherein the photosensitive layer has the general formula (I).

[0008]

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(In the formula, Ar ₁ may be substituted with a substituent selected from the group consisting of an alkyl group, an alkoxy group, a dialkylamino group, a halogen atom and a diphenylamino group which may have a substituent. Represents a good phenyl group, and Ar ₂ may be substituted with a substituent selected from the group consisting of an alkyl group, an alkoxy group, a dialkylamino group, a halogen atom and a diphenylamino group which may have a substituent. Represents a phenyl group, and Ar ₃ is substituted with a substituent selected from the group consisting of (1) an alkyl group, an alkoxy group, a dialkylamino group, a halogen atom, and a dibenzylamino group which may have a substituent. Phenyl group,
(2) pyrenyl group, (3) N-alkylcarbazole group, (4) N-alkylphenoxazinyl group, (5) dibenzothiophenyl group, (6) N-alkylphenothiazinyl group, (7) dibenzofuranyl Represents a group. And a butadiene compound represented by the formula (1).

In the butadiene compound represented by the general formula (I), an aromatic ring group or a heterocyclic group is substituted with an alkyl group, an alkoxy group, a dialkylamino group or a diphenylamino group which may have a substituent. Are particularly preferred. Among these, compounds in which at least one of Ar ₁ , Ar ₂ and Ar ₃ is a dialkylaminophenyl group, a diarylaminophenyl group or an alkoxyphenyl group, or _one of Ar ₁ and Ar ₃ is A butadiene compound having a dialkylaminophenyl group or an alkoxyphenyl group and the other group having the above-mentioned substituent other than the diarylamino group is more preferable.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The electrophotographic photosensitive member of the present invention comprises a conductive support and a photosensitive layer containing the butadiene compound represented by the general formula (I) formed thereon. The structure of can be adopted. Examples thereof are shown in FIGS.

The electrophotographic photosensitive member having the structure shown in FIGS. 1 and 2 is represented by the general formula (I) on the conductive support 1 and the charge generating layer 2 mainly composed of the charge generating substance. A photosensitive layer 4a or 4b comprising a charge transporting material containing a butadiene compound and a charge transporting layer 3 made of a binder resin is provided as necessary for forming the photosensitive layer. In the electrophotographic photoreceptor having the structure shown in FIG. 3, the charge generating substance 5 is dispersed on the conductive support 1 in the charge transfer medium 6 containing the butadiene compound represented by the general formula (I). The photosensitive layer 4c is provided.

In the case of the electrophotographic photoreceptor having the structure shown in FIGS. 1 and 2, the charge generating substance contained in the charge generating layer 2 generates charges, while the charge transporting layer 3 injects the charges. Receive and carry out the transportation. That is, the charge required for light attenuation is generated in the charge generating substance, and the charge is transported in the charge transport medium. In the electrophotographic photosensitive member having the structure shown in FIG. 3, the charge generating substance generates charges with respect to light, and the charges are transferred by the charge transfer medium.

The electrophotographic photosensitive member having the structure shown in FIG. 1 has a charge generating layer formed of a vapor deposition film of a charge generating substance, or fine particles of the charge generating substance in a solvent in which a binder resin is dissolved if necessary. A charge generation layer formed by coating and drying a dispersion obtained by dispersion, and a solution in which a charge transporting substance is used alone or, if necessary, a binder resin is used in combination, and the resulting solution is dried. It can be manufactured by forming a charge transport layer.

The electrophotographic photosensitive member having the structure shown in FIG. 2 is obtained by applying a solution in which a charge-transporting substance is used alone or, if necessary, a binder resin is used in combination, to a conductive support, followed by drying. And a charge-generating layer comprising a charge-transporting layer formed by vapor deposition of a charge-generating substance, or a dispersion liquid obtained by dispersing fine particles of the charge-generating substance in a solvent or a binder resin solution, followed by drying. It can be manufactured by forming a charge generation layer consisting of

In the electrophotographic photoreceptor having the structure shown in FIG. 3, fine particles of the charge generating substance are dispersed in a solution in which the charge transporting substance is used alone or, if necessary, a binder resin is used in combination, It can be produced by forming a photosensitive layer by coating and drying this on a conductive support.

In the case of the electrophotographic photoreceptor having the structure shown in FIGS. 1 and 2, the thickness of the photosensitive layer is preferably 5 μm or less, and particularly preferably 0.01 to 2 μm. The thickness of the charge transport layer is preferably in the range of 3 to 50 μm, particularly preferably in the range of 5 to 30 μm. In the case of the electrophotographic photoreceptor having the structure shown in FIG. 3, the thickness of the photosensitive layer is preferably in the range of 3 to 50 μm, particularly preferably 5 to 30 μm.

In the case of the electrophotographic photoreceptor having the structure shown in FIGS. 1 and 2, the proportion of the charge transport material in the charge transport layer is preferably in the range of 5 to 100% by weight, and in the range of 40 to 80% by weight. Is particularly preferable, and the proportion of the charge generating substance in the charge generating layer is preferably in the range of 5 to 100% by weight, particularly preferably in the range of 40 to 80% by weight. In the case of the electrophotographic photoreceptor having the structure shown in FIG. 3, the proportion of the charge transport material in the photosensitive layer is preferably in the range of 5 to 99% by weight, and the proportion of the charge generating material is in the range of 1 to 50% by weight. Is preferable, and a range of 3 to 20% by weight is particularly preferable.
In any of the electrophotographic photoreceptors having the structures shown in FIGS. 1 to 3, when the photosensitive layer has a structure in which a charge generating substance and / or a charge transporting substance is dispersed in a binder resin, A plasticizer and a sensitizer may be used together with the binder resin.

Examples of the conductive support used in the electrophotographic photosensitive member of the present invention include aluminum, copper, zinc,
Stainless steel, chrome, titanium, nickel, molybdenum,
Metals or alloys such as vanadium, indium, gold, platinum, etc.
Alternatively, a conductive compound such as a conductive polymer or indium oxide; paper, a plastic film, ceramics or the like coated, vapor-deposited or laminated with a metal or alloy such as aluminum, palladium, or gold, and the like; The body surface may be subjected to a chemical or physical treatment.

The electrophotographic photosensitive member of the present invention may have various shapes such as a drum shape, a flat plate shape, a sheet shape and a belt shape, although it depends on the support used.

As the charge generating substance used in the electrophotographic photoreceptor of the present invention, various substances can be used. For example, azo pigments such as monoazo pigments, disazo pigments and trisazo pigments; various metal phthalocyanines and metal-free metals. Phthalocyanine pigments such as phthalocyanine and naphthalocyanine;
Examples thereof include condensed polycyclic pigments such as perinone pigments, perylene pigments, anthraquinone pigments, and quinacridone pigments; squarylium dyes; azurenium dyes; thiapyrylium dyes; cyanine dyes.

Particularly, phthalocyanines are suitable because they have high sensitivity in an electrophotographic system using a long-wavelength light source such as a semiconductor laser or a light emitting diode.

The charge generating substance is not limited to those described here, and may be used alone or in combination of two or more when used.

The butadiene compound represented by the general formula (I) used in the present invention can be produced by the following method.

That is, reaction formula (1)

[0026]

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(Wherein Ar ₁ , Ar ₂ and Ar ₃ have the same definitions as those in the general formula (I)) and the dialkyl phosphite represented by the general formula (1) and the general formula (2) It can be easily obtained by reacting an aldehyde represented by the formula (1) with an aldehyde in the presence of a base at room temperature.

As the base used in this reaction,
For example, sodium hydroxide, potassium hydroxide, sodium amide, sodium methoxide, sodium tert.
-Butoxide, potassium tert-butoxide and the like can be mentioned.

Examples of the solvent used in this reaction include alcohols such as methanol and ethanol; ethers such as tetrahydrofuran and dioxane;
Examples thereof include amides such as N, N-dimethylformamide, N, N-dimethylacetamide, and N-methylpyrrolidone, and these solvents can be used as a mixture of two or more kinds.

The aldehyde represented by the general formula (2) is
N, N-dimethylformamide or N-methylformanilide and a Vilsmeier reaction with a compound represented by the general formula Ar ₃ H using an equimolar amount to a slight excess of phosphorus oxychloride or the like are carried out by a conventional method. Can be easily manufactured.

The dialkyl phosphite represented by the general formula (1) can be produced by the following reaction.

First step: Reaction formula (2)

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Second stage: Reaction formula (3)

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Third stage: reaction formula (4)

[Chemical 6]

Fourth stage: reaction formula (5)

[Chemical 7]

(In the above formula, Ar ₁ and Ar ₂ have the same definitions as those in the general formula (I). X represents a halogen atom, R represents an alkyl group, and NBS represents N.
-Represents bromosuccinimide. )

(First Step) The halogen compound represented by the general formula (3) is reacted with a trialkylphosphite to obtain the dialkyl phosphite represented by the general formula (4).

As the halogen compound represented by the general formula (3), any of a fluorine compound, a chlorine compound, a bromine compound and an iodine compound can be used, but a bromine compound or an iodine compound is preferable from the viewpoint of reactivity.

Examples of the trialkyl phosphite include triethyl phosphite, tripropyl phosphite, tributyl phosphite and the like.

(Second step) According to the reaction formula (1),
The propylene derivative represented by the general formula (6) can be synthesized by reacting the phosphite dialkyl ester represented by the general formula (4) with the aldehyde represented by the general formula (5).

The aldehyde represented by the general formula (5) is
It can be synthesized in the same manner as the aldehyde represented by the general formula (1).

(Third step) The propylene derivative represented by the general formula (6) is reacted with peroxide and N-bromosuccinimide under heating or by reacting with bromine to give the compound represented by the general formula (7). The bromine compound represented is obtained.

Examples of the peroxide include benzoyl peroxide and tert-butylperoxy-2.
-Ethyl hexanoate, di-tert-butyl peroxide, 1,1-bis (tert-butylperoxy) cyclohexane, tert-butylperoxybenzoate, n-butyl-4,4'-bis (tert-butylperoxide) Oxy) valerate and the like can be mentioned. The reaction solvent used in this reaction is preferably a nonpolar solvent such as carbon tetrachloride or benzene.

(Fourth Step) According to the first step, a bromine compound represented by the general formula (7) is reacted with a trialkylphosphite to obtain a dialkyl phosphite represented by the general formula (1). be able to.

The method of synthesizing the butadiene compound represented by the general formula (I) used in the present invention is not necessarily limited to the above-mentioned method, and other methods can be used. For example, instead of the halogen compound represented by the general formula (3), a halogen compound represented by the following general formula (8) or a dihalogen compound represented by the following general formula (9) is used and synthesized according to the above reaction. You can also

[0046]

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The halogen compound represented by the general formula (8) and the dihalogen compound represented by the general formula (9) are similar to the halogen compound represented by the general formula (3) from the viewpoint of reactivity, a bromine compound or iodine. Preference is given to using compounds.

Specific examples of the butadiene compound used in the present invention are shown below by the combination of Ar ₁ , Ar ₂ and Ar ₃ in the general formula (I), but the butadiene compound used in the present invention is not limited to these examples. It is not limited.

[0049]

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[0050]

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[0051]

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[0052]

[Chemical 12]

[0053]

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[0054]

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[0055]

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[0056]

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[0057]

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[0058]

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[0059]

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[0060]

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[0061]

[Chemical 21]

[0062]

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[0063]

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[0064]

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[0065]

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[0066]

[Chemical formula 26]

[0067]

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[0068]

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[0069]

[Chemical 29]

The electrophotographic photosensitive member of the present invention contains a butadiene compound represented by the general formula (I) as a charge transporting substance, but other known charge transporting substances may be used in combination, if necessary.

Examples of the charge transporting substance of the low molecular weight compound include pyrene; carbazoles such as N-ethylcarbazole, N-isopropylcarbazole and N-phenylcarbazole; N-methyl-N-phenylhydrazino-3.
-Methylidene-9-ethylcarbazole, N, N-diphenylhydrazino-3-methylidene-9-ethylcarbazole, p- (N, N-dimethylamino) benzaldehyde diphenylhydrazone, p- (N, N-diethylamino) benzaldehyde diphenyl Hydrazone, p-
(N, N-diphenylamino) benzaldehyde diphenylhydrazone, 1- [4- (N, N-diphenylamino) benzylideneimino] -2,3-dimethylindoline, N-ethylcarbazole-3-methylidene-N-aminoindoline, Hydrazones such as N-ethylcarbazole-3-methylidene-N-aminotetrahydroquinoline; 2,5-bis (p-diethylaminophenyl)-
Oxadiazoles such as 1,3,4-oxadiazole; 1-phenyl-3- (p-diethylaminostyryl) -5- (p-diethylaminophenyl) pyrazoline, 1- [quinolyl- (2)]-3 Pyrazolines such as-(p-diethylaminophenyl) pyrazolin; tri-p
-Tolylamine, N, N'-diphenyl-N, N'-bis (3-methylphenyl) -1,1'-biphenyl-
Aryl amines such as 4,4′-diamine; butadienes such as 1,1-bis (p-diethylaminophenyl) -4,4-diphenyl-1,3-butadiene; 4- (2,
2-diphenylethenyl) -N, N-diphenylbenzenamine, 4- (1,2,2-triphenylethenyl)
Examples thereof include styryls such as -N, N-diphenylbenzenamine.

Examples of the polymer compound include poly-N-vinylcarbazole, halogenated poly-N-vinylcarbazole, polyvinylpyrene, polyvinylanthracene, polyvinylacridine, poly-9-vinylphenylanthracene and pyrene-. Formamide resin, ethylcarbazole-formaldehyde resin, triphenylmethane polymer, polyphenylalkylsilane and the like can be mentioned.

The charge transport material is not limited to those described here, and may be used alone or in combination of two or more when used.

When these charge transport materials are used in combination with the butadiene compound of the present invention, the content of the butadiene compound of the present invention in the total charge transport material is 10% by weight.
As described above, preferably 20% or more.

When the photosensitive layer is formed, the binder resin that can be used as necessary is preferably a hydrophobic, electrically insulating polymer compound capable of forming a film. Examples of such high molecular weight polymers include polycarbonate, polyester, methacrylic resin, acrylic resin, polyvinyl chloride, polyvinylidene chloride, polystyrene, polyvinyl acetate, polyvinyl butyral, styrene-butadiene copolymer, vinyl chloride-vinyl acetate. -Maleic anhydride copolymer, silicone resin, silicone-alkyd resin, phenol-formaldehyde resin, styrene-alkyd resin, poly-N-vinylcarbazole, polyvinyl formal, polysulfone and the like.

The binder resin is not limited to those described here, and when used, it may be used alone or as a mixture of two or more kinds.

Further, the film forming property of the electrophotographic photosensitive member, flexibility,
In order to improve mechanical strength, well-known additives such as a plasticizer and a surface modifier may be used together with these binder resins.

Examples of the plasticizer include biphenyl, biphenyl chloride, o-terphenyl, p-terphenyl,
Dibutyl phthalate, diethyl glycol phthalate,
Examples include dioctyl phthalate, triphenylphosphoric acid, methylnaphthalene, benzophenone, chlorinated paraffin, polypropylene, polystyrene, various fluorohydrocarbons, and the like.

Examples of the surface modifier include silicon oil and fluorine resin.

Any known sensitizer can be used as the sensitizer used in the photosensitive layer as necessary.

Examples of the sensitizer include chloranil, tetracyanoethylene, methyl violet, rhodamine B, cyanine dye, merocyanine dye, pyrylium dye and thiapyrylium dye.

In the electrophotographic photosensitive member of the present invention, in order to improve storage stability, durability and environmental resistance, a photosensitive layer contains a deterioration inhibitor such as an antioxidant or a light stabilizer. You can also Examples thereof include phenol compounds, hydroquinone compounds, and amine compounds.

Further, in the electrophotographic photosensitive member of the present invention, the adhesion between the conductive support and the photosensitive layer is improved,
In order to prevent the injection of free charges from the conductive support to the photosensitive layer, an adhesive layer or a barrier layer may be provided between the conductive support and the photosensitive layer, if necessary.

Materials used for these layers include, in addition to the polymer compounds used for the binder resin, casein, gelatin, ethyl cellulose, nitrocellulose,
Carboxy-methylcellulose, vinylidene chloride-based polymer latex, styrene-butadiene-based polymer latex, polyvinyl alcohol, polyamide, polyurethane, phenolic resin, aluminum oxide, tin oxide,
Titanium oxide or the like can be used, and the film thickness is preferably 1 μm or less.

When the laminated electrophotographic photosensitive member is formed by coating, the solvent that dissolves the binder resin varies depending on the kind of the binder resin, but it is desirable to select from those that do not dissolve the lower layer. Specific examples of the organic solvent include alcohols such as methanol, ethanol and n-propanol; acetone, methyl ethyl ketone,
Ketones such as cyclohexanone; amides such as N, N-dimethylformamide, N, N-dimethylacetamide; ethers such as tetrahydrofuran, dioxane, methylcellosolve; esters such as methyl acetate, ethyl acetate; dimethyl sulfoxide, sulfolane, etc. Sulfoxides and sulfones; dichloromethane, chloroform,
Aliphatic halogenated hydrocarbons such as carbon tetrachloride and trichloroethane; aromatics such as benzene, toluene, xylene, monochlorobenzene, and dichlorobenzene.

As the coating method, for example, a coating method such as a dip coating method, a spray coating method, a spinner coating method, a bead coating method, a wire bar coating method, a blade coating method, a roller coating method or a curtain coating method can be used. it can.

The butadiene compound represented by the general formula (I) used in the present invention has good solubility in a solvent and excellent compatibility with a binder resin, and an electrophotographic photosensitive material containing this compound in a photosensitive layer. As is clear from the examples described below, the body has high sensitivity and is excellent in stability of electrophotographic characteristics during repeated use.

[0088]

EXAMPLES Examples will be shown below, but the present invention is not limited to these examples. In the following examples, all "parts" represent "parts by weight".

<Synthesis Example 1> (Synthesis of Exemplified Compound No. 7) 5.55 g (0.03 mol) of 1-bromoethylbenzene and 5.48 g (0.33 mol) of triethyl phosphite were placed in a round-bottomed flask having a capacity of 50 ml. , 120-130
The mixture was heated and stirred at 5 ° C for 5 hours. After completion of the reaction, unreacted substances were distilled off under reduced pressure to obtain 1-phenylethyl phosphorous acid diethyl ester.

In a reaction flask having a volume of 100 ml, 1-phenylethyl phosphite diethyl ester obtained above and 3.18 g (0.03 mol) of benzaldehyde, dimethylformamide (hereinafter referred to as D
Abbreviated as MF. ) 50 ml was charged, and the solution was stirred at room temperature to form a solution, which was then placed in a water bath and cooled to 20 ° C or lower. Then, potassium tert-butoxide 5.6 was added to this solution.
g was added little by little so that the reaction temperature did not exceed 35 ° C., and then the mixture was reacted at room temperature for 7 hours. After the reaction was completed, the reaction mixture was poured into 300 ml of water and extracted with 200 ml of methylene chloride. The extract was dried over sodium sulfate and then concentrated to obtain 4.0 g of α-methylstilbene white solid.

Next, in a reaction vessel having a capacity of 100 ml, 3.88 g (0.02 mol) of α-methylstilbene, 3.56 g (0.02 mol) of N-bromosuccinimide and 30 ml of carbon tetrachloride were placed, While stirring under reflux, tert
-Butylperoxy-2-ethylhexanoate 0.4
g was added little by little, and the mixture was reacted under reflux for 3 hours. After cooling the reaction mixture, suction filtration was performed and the resulting filtrate was concentrated to obtain α-bromomethylstilbene.

In a round-bottomed flask having a volume of 50 ml, α-bromomethylstilbene obtained above and triethyl phosphite 3.
Charge 65 g (0.022 mol), 120-130 ° C
The mixture was reacted for 15 hours with heating and stirring. After cooling the reaction mixture, unreacted triethyl phosphite was distilled off under reduced pressure to obtain 2,3-diphenylallyl phosphite diethyl ester.

Next, a reaction flask having a capacity of 200 ml was charged with the diethyl ester of 2,3-diphenylallyl phosphite obtained above and 4.6 g (0.02 mol) of pyrene-3-aldehyde, and α-methylstilbene was synthesized. A crude product of Exemplified Compound No. 7 was obtained with the same formulation as above. This crude product was purified by silica gel column chromatography (eluent: methylene chloride / hexane = 1/4 (volume ratio)) to give a purified product of Exemplified Compound No. 7 as a yellow powder 1.50.
g was obtained.

The elemental analysis of the purified product of Exemplified Compound No. 7 thus obtained was as follows. Calculated value (%) Measured value (%) C 94.58 94.49 H 5.42 5.51

Further, when a mass spectrum was measured using a mass spectrometer JMS-AX500 manufactured by JEOL Ltd., a peak was shown at m / z = 406.

Other exemplified compounds could be synthesized in the same manner as in Synthesis Example 1.

Example 1 2 parts of α-type titanyl phthalocyanine and 1 part of butyral resin (“S-REC BH-3” manufactured by Sekisui Chemical Co., Ltd.), 52 parts of dichloromethane and 78 parts of 1,1,2-trichloroethane. Was added to the mixed solvent consisting of, and dispersed and mixed in a sand mill to obtain a charge generating substance dispersion liquid.

The dispersion liquid obtained above was applied onto a polyester film on which aluminum was vapor-deposited so as to have a film thickness after drying of 0.2 μm, and dried to form a charge generation layer.

Next, 1.9 parts of No. 7 exemplified compound and 2.4 parts of a polycarbonate resin (“Upilon Z200” manufactured by Mitsubishi Gas Chemical Co., Inc.), 6.4 parts of 1,1,2-trichloroethane and dichloromethane. A paint for forming a charge transport layer was prepared by dissolving in a mixed solvent of 10.0 parts. This charge transport layer-forming coating material is applied onto the charge generation layer so that the film thickness after drying is 20 μm, and the charge transport layer is dried to form the charge transport layer, thereby having the structure shown in FIG. An electrophotographic photoreceptor was obtained.

This electrophotographic photosensitive member was charged by a corona discharge of -6 KV in a dark place by using an electrostatic copying paper tester ("SP428" manufactured by Kawaguchi Electric Co., Ltd.). Surface potential V _{0 of the} electrophotographic photosensitive member of
(V) was measured. Next, the surface potential V ₁₀ (V) of the electrophotographic photosensitive member when left as it is in a dark place for 10 seconds was measured. The potential holding ratio (DDR: (V ₁₀ / V ₀ ) × 100) of the surface potential of the electrophotographic photosensitive member was calculated from V ₀ and V ₁₀ . Furthermore, wavelength 780nm to the surface potential V _10, the exposure energy 1 .mu.W / cm ² of subjected to exposure with light, half-decay exposure than the time until the surface potential becomes half of V ₁₀ E _1/2 (μ
J / cm ² ) was determined. Furthermore, the residual potential V _R (V), which is the surface potential 15 seconds after the start of exposure, was measured. Table 1 shows the measurement results of darkness and light attenuation of the surface potential.

In addition, the process of charging, leaving in the dark for 1 second, exposing for 1 second, and removing static electricity by white light for 0.1 second was performed for 1,000 seconds.
Table 1 shows the measurement results immediately after the repetition.

<Examples 2 to 9> Electrophotographic sensitization was performed in the same manner as in Example 1 except that the exemplified compounds shown in Tables 1 and 2 below were used in place of the exemplified compound No. 7. The electrophotographic characteristics of these electrophotographic photosensitive members prepared by the same method as in Example 1 are shown in Tables 1 and 2.

<Comparative Example 1> In Example 1, instead of the exemplified compound No. 7, the structural formula (10) was used.

[0104]

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An electrophotographic photosensitive member was prepared in the same manner as in Example 1 except that the charge transporting material represented by the formula (1) was used, and the electrophotographic characteristics measured by the same method as in Example 1 are shown in Table 2.

<Comparative Example 2> In Example 1, instead of the exemplified compound No. 7, the structural formula (11) was used.

[0107]

[Chemical 31]

An electrophotographic photoreceptor was prepared in the same manner as in Example 1 except that the charge transporting material represented by the formula (1) was used, and the electrophotographic characteristics measured by the same method as in Example 1 are shown in Table 2.

[0109]

[Table 1]

[0110]

[Table 2]

<Example 10> In Example 1, 20 parts of oxytitanium phthalocyanine compound and (2R, 3R)-(-)-were used in place of the α-type titanyl phthalocyanine.
In a mass spectrum obtained by reacting 2.2 parts of 2,3-butanediol with 240 parts of α-chlornaphthalene at 195 to 205 ° C. for 1.5 hours with stirring, m / z = 576.
And 648, and the charge-generating substance dispersion prepared by using the phthalocyanine reaction product showing the spectrum of FIG. 4 in the powder X-ray diffraction by CuKα ray was used, and also used in the coating material for forming the charge transport layer. Instead of the polycarbonate resin (“Upilon Z200”), a polycarbonate resin (“Panlite C140 manufactured by Teijin Chemicals Ltd.
0 ") was used, an electrophotographic photosensitive member was prepared in the same manner as in Example 1, and the electrophotographic characteristics measured by the same method as in Example 1 are shown in Table 3.

<Examples 11 to 13> An electrophotographic photosensitive member was prepared in the same manner as in Example 10, except that the exemplified compounds shown in Table 3 were used instead of the exemplified compound No. 7. did. Further, the electrophotographic characteristics of these electrophotographic photosensitive members measured by the same method as in Example 1 are summarized in Table 3.

<Comparative Example 3> In Example 10, instead of the exemplified compound No. 7, the structural formula (12) was used.

[0114]

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An electrophotographic photosensitive member was prepared in the same manner as in Example 10 except that the charge transporting material represented by
The electrophotographic characteristics measured by the same method as in Example 1 are shown in Table 3.

[0116]

[Table 3]

As is clear from Tables 1 to 3, all the electrophotographic photosensitive members having a photosensitive layer containing the butadiene compound represented by the general formula (I) of the present invention have a high surface potential during corona charging. The surface potential retention rate was good, and the half-exposure amount was small and the sensitivity was good. Also, even after 1,000 times of repeated tests,
It had a good surface potential, a surface potential holding ratio and a good sensitivity, and further had a small residual potential after exposure.

Example 14 A solution was prepared by dissolving 1 part of a polyamide resin (“Amilan CM-8000” manufactured by Toray Industries, Inc.) in a mixed solvent consisting of 7 parts of methanol and 7 parts of n-butanol. This resin solution was applied to the outer peripheral surface of an aluminum drum having a diameter of 30 mm by a dip coating method so that the film thickness after drying was 1 μm, and dried to form a barrier layer.

Next, the charge generation material dispersion liquid used in Example 10 was applied onto the barrier layer by a dip coating method so that the film thickness after drying was 0.4 μm, and dried. A charge generation layer was formed.

On the charge generation layer, a blade coating method was applied so that the film thickness after drying was 20 μm.
The charge-transporting agent layer-forming coating material used in 1 was applied and dried to form a charge-transporting layer, to prepare a drum-shaped electrophotographic photosensitive member.

<Examples 15 to 16> In Example 14, the charge transfer agent layer-forming coating materials used in Examples 12 to 13 were used instead of the charge transfer agent layer-forming coating material used in Example 10. An electrophotographic photosensitive member was produced in the same manner as in Example 14 except that the above was used.

(Comparative Example 4) In Example 14, instead of the charge transport material used in Example 10, the structural formula (13) was used.

[0123]

[Chemical 33]

An electrophotographic photosensitive member was produced in the same manner as in Example 14 except that the charge transport material represented by

(Evaluation of Image Characteristics) The drum-shaped electrophotographic photoconductors produced in Examples 14 to 16 and Comparative Example 4 were mounted on a commercially available laser printer (“LaserJet 4” manufactured by Hewlett-Packard Co.) to obtain toner. The continuous printing was performed while replenishing the ink, and the image condition was evaluated.

Table 4 shows a list of the evaluation results at the initial stage and after the 10,000-sheet printing test.

[0127]

[Table 4]

As is clear from Table 4, the electrophotographic photoreceptor having the photosensitive layer containing the butadiene compound represented by the general formula (I) of the present invention has excellent compatibility with the binder resin. Image defects due to cracks, phase separation, and the like were less likely to occur, and the stability was high.

<Example 17> Exemplified compound No. 65
2 parts and polycarbonate resin (trade name "UPILON Z
200 "(manufactured by Mitsubishi Gas Chemical Co., Inc.) 0.35 parts of α-type titanyl phthalocyanine was added to a solution prepared by dissolving 2.75 parts in 24.7 parts of dichloromethane, and pulverized and mixed by a vibration mill to obtain a dispersion liquid. An electrophotographic photosensitive member having a structure shown in FIG. 3 is obtained by applying the dispersion liquid onto a polyester film on which aluminum is vapor-deposited using a wire bar so that the thickness after drying is 18 μm, and drying. Got

The electrophotographic characteristics of this electrophotographic photosensitive member were measured by the same method as in Example 1 except that the electrophotographic photosensitive member was charged by a corona discharge of +6 KV in a dark place using an electrostatic copying paper test apparatus. Table 6 shows the results
The measurement results after repeating 0 times are shown in Table 5.

<Comparative Example 5> In Example 17, No. 6
An electrophotographic photoreceptor was prepared in the same manner as in Example 17, except that the charge transporting material represented by the structural formula (10) used in Comparative Example 1 was used instead of the exemplified compound of Example 5. The electrophotographic photoreceptor was evaluated by the same method. The results are shown in Table 5.

[0132]

[Table 5]

As is clear from Table 5, the electrophotographic photosensitive member using the butadiene compound represented by the general formula (I) of the present invention has a high surface potential at the time of corona charging, and the surface potential retention rate. Was good, and the sensitivity was good with a small half-exposure amount. Further, it had a good surface potential, surface potential holding ratio and sensitivity even after 1,000 times of repeated operation, and further, the residual potential after exposure was small.

Example 18 A structural formula (14) was added to a resin solution containing 1 part of a phenoxy resin (“PKHH” manufactured by Union Carbide Co.) and 97 parts of dioxane.

[0135]

Embedded image

2 parts of the disazo pigment represented by the formula (1) was added and a charge generating substance dispersion liquid was prepared using a vibration mill.

The charge-generating substance dispersion liquid obtained above was applied on a polyester film on which aluminum was vapor-deposited so that the film thickness after drying was 1 μm, and dried to form a charge-generating layer.

Next, 1.9 parts of the No. 2 exemplified compound and 2.4 parts of a polycarbonate resin (trade name "UPILON Z200" manufactured by Mitsubishi Gas Chemical Co., Inc.) were added to 6.4 parts of 1,1,2-trichloroethane. A paint for forming a charge transport layer was prepared by dissolving in a mixed solvent of 10.0 parts of dichloromethane.

A film thickness after drying of 20 is formed on the charge generation layer.
This charge transport layer-forming coating material is applied so that the thickness becomes μm, and the charge transport layer is dried to form the charge transport layer.
An electrophotographic photosensitive member having the structure shown in was prepared.

With respect to this electrophotographic photosensitive member, the electrophotographic photosensitive member was charged by corona discharge of −6 KV in a dark place by using an electrostatic copying paper test apparatus, and the surface potential V ₀ (V ₀ (V ) Was measured. Next, 10 in the dark as it is
Surface potential V of electrophotographic photosensitive member when left for 2 seconds
₁₀ (V) was measured. From V ₀ and V _10, the potential holding ratio of the surface potential of the electrophotographic photosensitive member (DDR: (V ₁₀ / V ₀ ) × 10
0) was calculated. Further, by exposing the surface potential V ₁₀ with white light of 5 lux, the time (second) until the surface potential is reduced to half of the initial surface potential is obtained, and the photosensitivity E _1/2 (lu
x · sec). Furthermore, the residual potential V _R (V), which is the surface potential 15 seconds after the start of exposure, was measured. Table 6 shows the measurement results of dark decay and light decay of the surface potential.

In addition, the process of charging, leaving in the dark for 1 second, exposing for 1 second, and removing static electricity by white light for 0.1 second was performed for 1,000 seconds.
Table 6 shows the measurement results immediately after the repetition.

<Examples 19 to 20> In Example 18
An electrophotographic photosensitive member was produced in the same manner as in Example 18, except that the exemplified compounds shown in Table 8 were used instead of the exemplified compound of No. 2. Further, the electrophotographic characteristics of these electrophotographic photosensitive members measured by the same method as in Example 18 are summarized in Table 6.

<Comparative Example 6> No. 2 in Example 18
An electrophotographic photosensitive member was produced in the same manner as in Example 18 except that the charge transporting material represented by the structural formula (10) was used instead of the exemplified compound of No. 1, and the electrophotographic photosensitive material was prepared in the same manner as in Example 18. The body was evaluated. Table 6 shows the results.

[0144]

[Table 6]

As is clear from Table 6, all the electrophotographic photoreceptors having a photosensitive layer containing the butadiene compound represented by the general formula (I) of the present invention have a high surface potential during corona charging, and The surface potential retention rate is good,
In addition, the half exposure amount was small and the sensitivity was good.
Further, it had good surface potential, surface potential holding ratio and sensitivity even after 1,000 times of repeated test, and further, the residual potential after exposure was small.

[0146]

INDUSTRIAL APPLICABILITY The butadiene compound represented by the general formula (I) used in the present invention has excellent solubility in a solvent and compatibility with a binder resin. An electrophotographic photoreceptor having a photosensitive layer containing this compound as a photoconductive material,
High sensitivity and excellent stability of electrophotographic characteristics during repeated use.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view showing an example of a layer structure that can be taken by an electrophotographic photosensitive member of the present invention.

FIG. 2 is a schematic cross-sectional view showing an example of a layer structure that the electrophotographic photosensitive member of the present invention can take.

FIG. 3 is a schematic cross-sectional view showing an example of a layer structure that the electrophotographic photosensitive member of the present invention can take.

FIG. 4 is an X-ray diffraction spectrum diagram of the phthalocyanine used in Example 11.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Conductive support 2 Charge generating layer 3 Charge transporting layer 4a Photosensitive layer 4b Photosensitive layer 4c Photosensitive layer 5 Charge generating substance 6 Charge transfer medium 7 Electrophotographic photoreceptor

Claims (3)

[Claims] 1. An electrophotographic photosensitive member having a photosensitive layer on a conductive support, wherein the photosensitive layer has the general formula (I): (In the formula, Ar ₁ is an alkyl group, an alkoxy group,
Represents a phenyl group which may be substituted with a substituent selected from the group consisting of a dialkylamino group, a halogen atom and a diphenylamino group which may have a substituent, and Ar ₂ represents an alkyl group, an alkoxy group or a dialkyl group. Represents a phenyl group which may be substituted with a substituent selected from the group consisting of an amino group, a halogen atom and a diphenylamino group which may have a substituent;
r ₃ is a phenyl group which may be substituted with a substituent selected from the group consisting of (1) an alkyl group, an alkoxy group, a dialkylamino group, a halogen atom and a dibenzylamino group which may have a substituent. , (2) pyrenyl group, (3) N-alkylcarbazole group, (4) N-
Alkylphenoxazinyl group, (5) dibenzothiophenyl group, (6) N-alkylphenothiazinyl group,
(7) represents a dibenzofuranyl group. An electrophotographic photoreceptor containing a butadiene compound represented by the formula (1). 2. In the general formula (I), Ar ₁ and Ar ₂
The electrophotographic photosensitive member according to claim 1, further comprising a butadiene compound in which at least one of Ar ₃ and Ar ₃ is a dialkylaminophenyl group, a diarylaminophenyl group or an alkoxyphenyl group. 3. In the general formula (I), Ar ₁ and Ar
_The electrophotographic photosensitive member according to claim 1, wherein one of the groups ₃ is a dialkylaminophenyl group or an alkoxyphenyl group, and the other group contains a butadiene compound having a substituent other than the diarylamino group.