JPH05112501A - Butadiene derivative and electroph0t0graphic photoreceptor using the same - Google Patents

Abstract

PURPOSE:To obtain a new butadiene derivative, having the high charge transfer ability, excellent in light stability and capable of providing electrophotographic photoreceptors, having high sensitivity and improved in durability. CONSTITUTION:A compound expressed by formula I [R<1> to R<3> are H, substitutable alkyl or alkoxy; (n) is 1-5]. The compound expressed by formula I is obtained by converting a 4-bromo-p-terphenyl derivative expressed by formula II into a Grignard reagent, reacting the resultant Grignard reagent with a 4-acetyl-p-terphenyl derivative expressed by formula III, then reacting the obtained 1,1-di(p-terphenylyl)ethylene derivative expressed by formula IV with a Vilsmeier reagent obtained from N,N-dimethylformamide and phosphorus oxychloride, affording an acrolein derivative expressed by formula V and reacting the prepared acrolein derivative with a trialkyl 1,1- diphenylmethylphosphite derivative expressed by formula VI (R<6> is 1-4C alkyl).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a butadiene derivative suitable as a charge transport material in an electrophotographic photosensitive member used in an electrostatic copying machine, a laser beam printer, etc., and an electrophotographic photosensitive member using the same. It is a thing.

[0002]

2. Description of the Related Art In recent years, organic photoconductors are widely used as photoconductors in image forming apparatuses such as copying machines because they are excellent in processability and economy and have a high degree of freedom in functional design. The Carlson process is widely used to form a copied image using a photoconductor. The Carlson process consists of a charging process that uniformly charges the photoconductor by corona discharge, an exposure process that exposes the document image on the charged photoconductor to form an electrostatic latent image corresponding to the document image, and an electrostatic latent image. After development with a developer containing toner, a developing step of forming a toner image, a transfer step of transferring the toner image to paper, a fixing step of fixing the transferred toner image, and a transfer step,
And a cleaning step for removing the toner remaining on the photoconductor. In order to form a high-quality image in the Carlson process, the photoconductor is required to have excellent charging properties and photosensitivity, and to have a low residual potential after exposure.

Conventionally, inorganic photoconductors such as selenium and cadmium sulfide have been known as photosensitive materials, but they have the drawbacks of toxicity and high production cost. Therefore, so-called organic photoconductors using various organic substances in place of these inorganic substances have been proposed. Such an organophotoreceptor has a photosensitive layer composed of a charge generating material that generates a charge upon exposure and a charge transporting material that has a function of transporting the generated charge.

In order to satisfy various conditions desired for such an organic photoreceptor, it is necessary to appropriately select these charge generating material and charge transporting material. Various organic compounds such as carbazole-based compounds, oxadiazole-based compounds, pyrazoline-based compounds, hydrazone-based compounds, and butadiene-based compounds have been proposed as charge transport materials. Examples of the butadiene-based compound include, for example, JP-A-62-1
Examples thereof include compounds represented by the following formula (i) disclosed in Japanese Patent No. 287257.

[0005]

[Chemical 2]

[In the formula, R ⁴ represents a di-lower alkylamino group, and R ⁵ represents a hydrogen atom or a di-lower alkylamino group. ]

[0007]

However, the above equation
Conventional charge-transporting materials such as butadiene compounds represented by (i) have problems of insufficient charge-transporting ability and poor photostability. The photoconductor used has a drawback that the sensitivity and durability are not sufficient.

An object of the present invention is to provide a butadiene derivative which has excellent charge transporting ability and photostability and is suitable as a charge transporting material.
To provide an electrophotographic photosensitive member using the same, which has high sensitivity and excellent durability.

[0009]

In order to solve the above-mentioned problems, the butadiene derivative of the present invention has the general formula
(I):

[0010]

[Chemical 3]

[Wherein R ¹ , R ² and R ³ are the same or different and each represents a hydrogen atom, or an alkyl group or an alkoxy group which may have a substituent, and n represents an integer of 1 to 5]. .. ] Is represented. Further, the electrophotographic photosensitive member of the present invention for achieving the above object, on the conductive substrate,
It is characterized in that a photosensitive layer containing the butadiene derivative represented by the general formula (I) is provided.

Since the butadiene derivative represented by the above general formula (I) has a structure of p-terphenyl known as a quencher introduced into the molecule, it exhibits a high charge transporting ability and also exhibits photostability. Are better. Therefore, the photosensitive layer containing the butadiene derivative as a charge transport material has high sensitivity and excellent durability.
Thus, the reason why the butadiene derivative represented by the general formula (I) has high sensitivity and photostability is, for example, that p-terphenyl is higher than that of the compound represented by the above formula (i). Since the π-electron conjugated system formed in the molecule has a larger extent by the amount of the introduced portion, the planarization of the molecular structure of the compound is further promoted, and the intermolecular interaction due to the overlap between molecules and the like. Is presumed to be due to

The butadiene derivative represented by the general formula (I) basically contains a butadiene derivative represented by the following general formula (Ia).

[0014]

[Chemical 4]

[In the formula, R ¹ , R ² and R ³ represent the same groups as described above, and n represents an integer of 1 to 5. Examples of the alkyl group include lower alkyl groups having 1 to 6 carbon atoms such as methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, t-butyl group, pentyl group and hexyl group.

Examples of the alkoxy group include lower alkoxy having 1 to 6 carbon atoms such as methoxy group, ethoxy group, propoxy group, isopropoxy group, butoxy group, isobutoxy group, t-butoxy group, pentyloxy group and hexyloxy group. The group can be raised. In addition, examples of the substituent for substituting the above alkyl group and the like include a halogen atom, an amino group, a hydroxyl group, an optionally esterified carboxyl group, a cyano group, an alkyl group having 1 to 6 carbon atoms, and 1 to 1 carbon atoms.
And an alkenyl group having 2 to 6 carbon atoms, which may have an alkoxy group having 6 or an aryl group.

Specific compounds of the butadiene derivative represented by the general formula (I) include, for example, the following formulas (A1) to (A4).
The ones shown in are listed.

[0018]

[Chemical 5]

[0019]

[Chemical 6]

The butadiene derivative of the present invention can be synthesized by various methods. For example, the above-mentioned general formula (Ia)
The butadiene derivative represented by can be easily produced according to the procedure shown below. First, as shown in the following reaction formula, a 4-bromo-p-terphenyl derivative represented by the general formula (1) is reacted with magnesium in an organic solvent such as tetrahydrofuran to give a compound represented by the general formula (2). Obtain the Grignard reagent represented.

[0021]

[Chemical 7]

[In the formula, R ³ represents the same group as described above, and n represents an integer of 1 to 5. Next, as shown in the following reaction formula, the Grignard reagent (2) is reacted with the acetyl-p-terphenyl derivative represented by the general formula (3) and treated with a saturated ammonium chloride aqueous solution, A 1,1-di (p-terphenylyl) ethylene derivative represented by the general formula (4) is obtained, and the 1,1-di (p-terphenylyl) ethylene derivative (4) is prepared according to the method of H. Lovenz et al. . Chim. Acta.
, 28 , 600-612 (1945)], and is reacted with a Wiersmeier reagent obtained from N, N-dimethylformamide and phosphorus oxychloride to give the 3,3-dicarboxylic acid represented by the general formula (5). A (p-terphenylyl) acrolein derivative is obtained.

[0023]

[Chemical 8]

[In the formula, R ³ represents the same group as described above, and n represents an integer of 1 to 5. ] Then, as shown in the following reaction formula, the above-mentioned 3,3-di (p-terphenylyl) acrolein derivative (5) is equimolar or slightly in excess with the general formula (6).
By reacting with a 1,1-diphenylmethylphosphorous acid trialkyl derivative represented by the formula (1), a butadiene derivative represented by the general formula (Ia) is obtained.

[0025]

[Chemical 9]

[Wherein R ¹ , R ² and R ³ represent the same groups as described above, R ⁶ represents a lower alkyl group having 1 to 4 carbon atoms,
n shows the integer of 1-5. The above reaction is carried out in the presence of a basic catalyst in an organic solvent at a temperature of room temperature to 80 ° C. The basic catalyst used in the reaction includes sodium hydride, sodium amide, caustic soda, caustic potash, sodium methylate, sodium-te
Examples thereof include alcoholates such as rt-butoxide and potassium-tert-butoxide.

As the organic solvent, lower alcohols such as methanol, ethanol, isopropanol, butanol and 2-methoxyethanol; ethers such as 1,2-dimethoxyethane, bis (2-methoxyethyl) ether, dioxane and tetrahydrofuran; toluene, Aromatic hydrocarbons such as xylene; dimethyl sulfoxide, N,
N-dimethylformamide, N-methylpyrrolidone,
Examples include aprotic polar solvents such as 1,3-dimethyl-2-imidazolidinone and the like. Among them, polar solvents such as N, N-dimethylformamide and dimethyl sulfoxide are preferably used.

The reaction temperature is the stability of the solvent used with respect to the basic catalyst, the reactivity of the compound represented by the above formulas (5) and (6) as the condensation component, and the reaction of the basic catalyst as the condensation agent. It is selected in a wide range depending on the sex. For example, the reaction temperature when a polar solvent is used is from room temperature to 8
Set to 0 ° C. The reaction temperature when using a basic catalyst having a short reaction time or low activity as a condensing agent is set to a temperature higher than the above.

The 1,1-diphenylmethyl trialkyl phosphite derivative represented by the general formula (6) has a corresponding haloalkyl compound and trialkyl phosphite (wherein the alkyl group has 1 to 4 carbon atoms as described above). And a lower alkyl group, especially a methyl group and an ethyl group are preferably heated) directly or in a solvent such as toluene or xylene.

The photoreceptor of the present invention is provided with a photosensitive layer containing one or more butadiene derivatives represented by the above general formula (I) as a charge transport material. The photosensitive layer includes a so-called single layer type and a laminated type, but the present invention is
It is applicable to any of these. In order to obtain a single-layer type photoreceptor, a photosensitive layer containing a compound represented by the general formula (I), which is a charge transport material, a charge generating material, a binder resin, etc., is applied by means such as coating. It may be formed on the conductive substrate.

In order to obtain a laminated type photoreceptor, a charge generation layer containing a charge generation material is formed on a conductive substrate by means such as vapor deposition or coating, and on this charge generation layer,
A charge transport layer containing the compound represented by the general formula (I) and a binder resin may be formed. Also, contrary to the above,
The charge transport layer may be formed on the conductive substrate, and then the charge generation layer may be formed. Further, in the above-mentioned laminated type photosensitive layer, the charge generating layer may also contain a charge transport material.

As the charge generating material, conventionally used selenium, selenium-tellurium, selenium-arsenic, amorphous silicon, pyrylium salt, azo compounds, disazo compounds, phthalocyanine compounds, anthanthrone compounds, perylene compounds. Examples thereof include compounds, indigo compounds, triphenylmethane compounds, slene compounds, toluidine compounds, pyrazoline compounds, perylene compounds, quinacridone compounds, and pyrrolopyrrole compounds. These charge generation materials can be used alone or in combination of two or more so that they have an absorption wavelength region in a desired region.

The butadiene derivative represented by the general formula (I), which is a charge transport material, can be used alone or in combination with other conventionally known charge transport materials. As the conventionally known charge transport material, various electron-withdrawing compounds and electron-donating compounds can be used. Examples of the electron-withdrawing compound include 2,6-dimethyl-
Diphenoquinone derivatives such as 2 ', 6'-ditert-dibutyldiphenoquinone, malononitrile, thiopyran compounds, tetracyanoethylene, 2,4,8-trinitrothioxanthone, 3,4,5,7-tetranitro-9.
Examples include fluorenone, dinitrobenzene, dinitroanthracene, dinitroacridine, nitroanthraquinone, dinitroanthraquinone, succinic anhydride, maleic anhydride, and dibromomaleic anhydride.

Further, as the electron donating compound, 2,5
-Oxadiazole compounds such as di (4-methylaminophenyl) and 1,3,4-oxadiazole, 9- (4
-Styryl compounds such as diethylaminostyryl) anthracene, carbazole compounds such as polyvinylcarbazole, pyrazoline compounds such as 1-phenyl-3- (p-dimethylaminophenyl) pyrazoline, hydrazone compounds, triphenylamine compounds, indole compounds Examples thereof include nitrogen-containing cyclic compounds such as compounds, oxazole compounds, isoxazole compounds, thiazole compounds, thiadiazole compounds, imidazole compounds, pyrazole compounds, and triazole compounds, and condensed polycyclic compounds.

These charge transport materials are used alone or in combination of two or more. When a charge transporting material having film-forming property such as polyvinylcarbazole is used,
The binder resin is not always necessary. As a binder resin,
Various resins can be used. For example, styrene-based polymer, styrene-butadiene copolymer, styrene-acrylonitrile copolymer, styrene-maleic acid copolymer, acrylic copolymer, styrene-acrylic acid copolymer, polyethylene, ethylene-vinyl acetate copolymer , Chlorinated polyethylene, polyvinyl chloride, polypropylene,
Thermoplastic resin such as vinyl chloride-vinyl acetate copolymer, polyester, alkyd resin, polyamide, polyurethane, polycarbonate, polyarylate, polysulfone, diallyl phthalate resin, ketone resin, polyvinyl butyral resin, polyether resin, or silicone resin, Examples thereof include epoxy resins, phenol resins, urea resins, melamine resins, other crosslinkable thermosetting resins, and photocurable resins such as epoxy acrylate and urethane-acrylate. These binder resins may be used alone or in combination of two or more.

The organic photosensitive layers of single-layer type and laminated type include
A sensitizer, a fluorene compound, an antioxidant, a deterioration inhibitor such as an ultraviolet absorber, and an additive such as a plasticizer may be contained. Further, in order to improve the sensitivity of the charge generation layer, known sensitizers such as terphenyl, halonaphthoquinones, and acenaphthylene may be used in combination with the charge generation material.

In the multi-layer type photoreceptor, the charge generating material and the binder resin constituting the charge generating layer can be used in various proportions, but to 100 parts of binder resin (parts by weight, the same applies hereinafter). 5 to 500 parts, especially 10 to 10 parts of the charge generating material.
It is preferably used in a ratio of 300 parts. The charge generation layer may have an appropriate film thickness, but 0.01 to 5
It is preferably formed to a thickness of 0.1 μm, particularly 0.1 to 3 μm.

The butadiene derivative (charge transport material) represented by the general formula (I) constituting the charge transport layer and the binder resin may be mixed in various amounts within a range that does not inhibit charge transport and a range that does not crystallize. The butadiene derivative represented by the general formula (I) can be used in a proportion of 100 parts by weight of the binder resin so that the charge generated in the charge generation layer by light irradiation can be easily transported. ~ 500 parts, especially 25 ~
It is preferably used in a ratio of 200 parts. The thickness of the laminated photosensitive layer is about 0.01 to 5 μm for the charge generation layer,
Particularly, it is preferable that the thickness is about 0.1 to 3 μm,
The charge transport layer is preferably formed to have a thickness of 2 to 100 μm, particularly 5 to 50 μm.

In the case of a single-layer type photoreceptor, the binder resin 10
The charge generating material is 0.1 to 50 parts relative to 0 parts, and more preferably 0.1.
5 to 30 parts, 40 to 200 parts, especially 50 to 10 parts by weight of the butadiene derivative (charge transport material) represented by the general formula (I).
Suitably 0 copy. The thickness of the single-layer type photosensitive layer is preferably 5 to 100 μm, particularly preferably 10 to 50 μm.

In the case of a single-layer type electrophotographic photosensitive member, between the conductive substrate and the photosensitive layer, in the case of the laminated type photosensitive member, between the conductive substrate and the charge generating layer, Between the conductive substrate and the charge transport layer, or between the charge generation layer and the charge transport layer, a barrier layer may be formed to the extent that the characteristics of the photoreceptor are not impaired, and the surface of the photoreceptor is A protective layer may be formed.

As the conductive substrate on which the above layers are formed, various conductive materials can be used.
For example, simple metals such as aluminum, copper, tin, platinum, silver, vanadium, molybdenum, chromium, cadmium, titanium, nickel, palladium, indium, stainless steel, and brass, plastic materials in which the above metals are vapor-deposited or laminated, and iodide Examples thereof include glass coated with aluminum, tin oxide, indium oxide, or the like.

The conductive substrate may be in the form of a sheet, a drum or the like, as long as the substrate itself has conductivity or the surface of the substrate has conductivity. Further, the conductive substrate is preferably one having sufficient mechanical strength when used. When each of the above layers is formed by a coating method, the charge generation material, charge transport material, and
A binder resin and the like are mixed with a suitable solvent by a known method, for example, a roll mill, a ball mill, an attritor, a paint shaker or an ultrasonic disperser to prepare a coating solution, which is prepared by a known means. It may be applied and dried.

As the solvent for forming the coating solution, various organic solvents can be used. For example, alcohols such as methanol, ethanol, isopropanol and butanol,
Aliphatic hydrocarbons such as n-hexane, octane and cyclohexane, aromatic hydrocarbons such as benzene, toluene and xylene, halogenated hydrocarbons such as dichloromethane, dichloroethane, carbon tetrachloride and chlorobenzene, dimethyl ether, diethyl ether, tetrahydrofuran, Examples thereof include ethers such as ethylene glycol dimethyl ether and diethylene glycol dimethyl ether, ketones such as acetone, methyl ethyl ketone and cyclohexanone, esters such as ethyl acetate and methyl acetate, dimethylformaldehyde, dimethylformamide and dimethyl sulfoxide. These solvents may be used alone or in combination of two or more.

Further, a surfactant, a leveling agent or the like may be used in order to improve the dispersibility of the charge transporting material or the charge generating material and the dyeing property. As described above, the charge generation layer may be formed by depositing the charge generation material.

[0045]

The present invention will be described in detail below with reference to examples and comparative examples. Example 1 <Synthesis of the butadiene derivative represented by the formula (A1)> 2 g of magnesium and 25.0 g (0 of 4-bromo-p-terphenyl) in which R ³ in the general formula (1) is a hydrogen atom. .0
81 mol) and 100 ml of tetrahydrofuran are mixed,
The reaction was carried out at room temperature to obtain a tetrahydrofuran solution of p-terphenylmagnesium bromide as a Grignard reagent.

Next, while stirring the solution, at room temperature, 16.9 g (0.081 mol) of 4-acetyl-p-terphenyl in which R ³ in the general formula (3) is a hydrogen atom.
After adding 100 ml of a benzene solution containing the above, the mixture was further stirred under reflux for 5 hours. After 5 hours, the reaction solution was cooled, and then 200 ml of a saturated aqueous solution of ammonium chloride was added thereto for hydrolysis, and the oil layer was separated from the reaction solution separated into two layers, an oil layer and an aqueous layer, and the oil layer was washed with water. After separating the oil layer again, the organic solvent was distilled off to obtain a residue.

This residue was dissolved in benzene, 0.1 g of p-toluenesulfonic acid was added, the mixture was stirred under reflux for 1 hour, the solvent was distilled off, and the obtained oily residue was subjected to silica gel column chromatography. Separation and purification gave 15.3 g (yield 38%) of oily product. Analysis of the obtained product revealed that R ³ in the general formula (4) was 1,1-di (p-terphenylyl) ethylene which is a hydrogen atom.

Next, N, N-dimethylformamide 2.
A solution of 2 g and 50 ml of 1,2-dichloroethane in 0-5
3.9 g of phosphorus oxychloride was added dropwise while cooling to 0 ° C., and stirring was continued for 30 minutes while maintaining the above liquid temperature to prepare a Wiersmeier reagent. Then, while maintaining the above liquid temperature in the Wielsmeier reagent, the 1, 1
10.6 g of di- (p-terphenylyl) ethylene (0.
50 ml of a 1,2-dichloroethane solution containing 022 mol)
Was added dropwise over 30 minutes.

Then, after refluxing and stirring for further 5 hours, 100 ml of water containing 10 g of sodium acetate was added for hydrolysis, and the oil layer was separated from the reaction solution separated into two layers, an oil layer and an aqueous layer. The oil layer was washed with water, the oil layer was separated again, and then the organic solvent was distilled off to obtain an oily residue. The residue was separated and purified by silica gel column chromatography to obtain 6.42 g (yield 57%) of an oily product. Analysis of the obtained product revealed that R ³ in the general formula (5) was 3,3-di (p-terphenylyl) acrolein, which is a hydrogen atom.

Next, 5.63 g (0.011 mol) of the above 3,3-di (p-terphenylyl) acrolein, R ¹ and R ² in the general formula (6) are both hydrogen atoms, and R ⁶ is An ethyl group of 1,1-di (4-amino) phenylmethyl triethyl phosphite (3.66 g, 0.011 mol),
Dissolved in 100 ml of N, N-dimethylformamide, stirred and at room temperature, potassium-tert-butoxide 1.23
g was added. Although the liquid temperature of the reaction liquid rose to 31 ° C. due to heat generation, the mixture was refluxed and stirred for 4 hours without cooling, and then poured into 100 ml of ice water and stirred to stop the reaction.

The precipitated crystals are separated by filtration, dried, dissolved in benzene, separated and purified by silica gel column chromatography, and the benzene is distilled off and recrystallized with ethyl acetate to obtain the above-mentioned formula ( 4.57 g of pale yellow crystals of the butadiene derivative represented by A1) (yield 60
%) Was obtained. The analysis results of the obtained butadiene derivative are shown below.

Elemental analysis result Calculated value (%): C 90.14 H: 5.82
N: 4.04 measured value (%): C: 90.14 H: 5.88
N: 4.06 mass spectrometric analysis C ₅₂ H ₄₀ N ₂ m / e = 692 (calculated value 692.9) Example 2 <Synthesis of butadiene derivative represented by the formula (A2)> Used in Example 1 In place of triethyl 1,1-di (4-amino) phenylmethyl phosphite, R ¹ and R ² in the general formula (6) are both methyl groups, and R ⁶ is an ethyl group.
1-Di {4- (N, N-dimethyl) -amino} phenylmethyl triethyl phosphite 3.95 g (0.011 mol)
5.11 g (yield: 6) of the butadiene derivative represented by the formula (A2) was obtained in the same manner as in Example 1 except that
2%) was obtained.

The analysis results of the obtained butadiene derivative are shown below. Elemental analysis result Calculated value (%): C: 89.80 H: 6.46
N: 3.74 Found (%): C: 89.78 H: 6.50
N: 3.70 Mass spectrometry result C ₅₆ H ₄₈ N ₂ m / e = 748 (calculated value 749.0) Example 3 <Synthesis of butadiene derivative represented by the formula (A3)> Used in Example 1 In place of triethyl 1,1-di (4-amino) phenylmethylphosphite, 1,1-di {4 in which R ¹ , R ² and R ^{6 in the} general formula (6) are both ethyl groups
Represented by the formula (A3) in the same manner as in Example 1 except that 4.26 g (0.011 mol) of-(N, N-diethyl) -amino} phenylmethyl triethyl phosphite was used. 5.05 g (yield 57%) of a butadiene derivative was obtained.

The analysis results of the obtained butadiene derivative are shown below. Elemental analysis results Calculated value (%): C: 89.51 H: 7.01
N: 3.48 Found (%): C: 89.55 H: 6.98
N: 3.47 mass spectrometry result as C ₆₀ H ₅₆ N ₂ m / e = 804 (calculated value 805.1) Example 4 <Synthesis of butadiene derivative represented by the formula (A4)> Used in Example 1 In place of 4-bromo-p-terphenyl, 4-bromo-4 ″ -methyl-p-terphenyl 2 is a methyl group in which R ³ in the general formula (1) is substituted at the 4 ″ position.
6.2 g (0.081 mol) was used, and in place of 4-acetyl-p-terphenyl used in Example 1, n in the general formula (3) was 1 and R ³ was in the 4 ″ position. In the same manner as in Example 1 except that 21.8 g (0.081 mol) of 4-acetyl-4 ″ -methyl-p-terphenyl, which is a substituted methyl group, was used, the above formula (A4) was used. 4.75 g (60% yield) of the butadiene derivative represented was obtained.

The analysis results of the obtained butadiene derivative are shown below. Elemental analysis result Calculated value (%): C: 89.96 H: 6.15
N: 3.89 Found (%): C: 89.94 H: 6.20
N: 3.90 mass spectrometry result as C ₅₄ H ₄₄ N ₂ m / e = 720 (calculated value 720.9) Examples 5 to 8 and Comparative Examples 1 and 2 (multilayer photoreceptor) In the following formula (A) 2 parts of the charge generation material shown, 1 part of polyvinyl butyral resin, and 120 parts of tetrahydrofuran were dispersed for 2 hours with a paint shaker using glass beads (2 mm diameter). The obtained dispersion was applied on the surface of an aluminum tube by a dipping method and dried at 100 ° C. for 1 hour to form a 0.5 μm charge generation layer.

[0056]

[Chemical 10]

A solution prepared by dissolving 1 part of the charge transport material prepared in Examples 1 to 4 and 1 part of polyester resin in 9 parts of toluene was applied onto the charge generation layer by a dipping method to obtain 100 parts.
After drying at 1 ° C. for 1 hour, a 22 μm-thick charge transport layer was formed to obtain a negative charging type laminated photoreceptor. The charge-transporting material used is shown in Table 1 and corresponds to each Example.
It is shown by the numbers 1) to (A4).

In Comparative Example 1, a compound in which R ⁴ in the above general formula (i) is a diethylamino group and R ⁵ is a hydrogen atom, and Comparative Example 2 is a compound represented by the following formula (ii), respectively. Laminated photoreceptors were prepared in the same manner as in Examples 5 to 8 except that they were used as materials.

[0059]

[Chemical 11]

Examples 9 to 12 and Comparative Examples 3 and 4 (single layer
Type Photoreceptor) 1 part of the charge generating agent represented by the above formula (A) and 60 parts of tetrahydrofuran were dispersed for 2 hours in a paint shaker using glass beads (2 mm diameter). To the obtained dispersion liquid, tetrahydrofuran solution of polyester resin 50
Parts, and the charge transport material 1 produced in Examples 1 to 4 above.
0 part was added and dispersion was continued for another hour. The obtained dispersion is applied to the surface of an aluminum tube by a dipping method,
A photosensitive layer having a thickness of μm was formed to obtain a positive charging type single-layer type photosensitive member. The charge transport materials used are shown in Table 2 by the numbers of the above-mentioned formulas (A1) to (A4) corresponding to the respective examples.

Comparative Example 3 is a compound in which R ⁴ in the general formula (i) is a diethylamino group and R ⁵ is a hydrogen atom, and Comparative Example 4 is a compound represented by the above formula (ii). Single-layer photoconductors were produced in the same manner as in Examples 9 to 12 except that they were used as materials. The following tests were carried out on the electrophotographic photosensitive members of the above Examples and Comparative Examples to evaluate their characteristics.

Measurement of Initial Surface Potential Each electrophotographic photosensitive member was loaded in an electrostatic copying tester (Gentec Cynthia 30M, trade name, manufactured by Gentech), and the surface thereof was charged positively or negatively. The surface potential Vs.p. (V) was measured. Measurement of half-exposure amount and residual potential The electrophotographic photosensitive member charged in the above-mentioned measurement of the initial surface potential is exposed under a condition of an exposure intensity of 10 lux by using a halogen lamp which is an exposure light source of an electrostatic copying tester. do it,
The half-exposure amount E1 / 2 (lux.sec) was calculated by obtaining the time until the surface potential became 1/2.

The surface potential was measured at 0.15 seconds after the start of the exposure, and the residual potential V1r.p. (V) was measured.
And Measurement of Light Stability The electrophotographic photosensitive member was loaded in an electrostatic copying machine (model number DC-111 manufactured by Mita Kogyo Co., Ltd.) to continuously copy 1000 sheets, and then repeatedly exposed in the same manner as above. After that, the residual potential V2r.p. (V) was measured. Then, the residual potential V
The difference ΔVr.p. (V) between 1r.p. and V2r.p. was obtained.

The test results of the laminated type photoreceptors (Examples 5 to 8 and Comparative Examples 1 and 2) are shown in Table 1, and the single layer type photoreceptor (Example 9).
Table 12 shows the test results of ~ 12 and Comparative Examples 3 and 4).

[0065]

[Table 1]

[0066]

[Table 2]

From these test results, there is almost no difference in the surface potential VS.P. between the laminated type and the single layer type of the photoconductors of the respective examples, although the surface potential VS.P. ,
It was found that the sensitivity was remarkably improved because the half exposure amount E1 / 2 was small and the residual potential V1r.p. was low. In addition, the photoconductors of the above respective examples have Δ
Since the Vr.p. was small, it was found that each of them had excellent durability.

[0068]

INDUSTRIAL APPLICABILITY As described above, the butadiene derivative of the present invention has a high charge transporting ability and excellent light stability. Therefore, by using this butadiene derivative as a charge transporting material, high sensitivity can be obtained. And an electrophotographic photoreceptor having excellent durability can be obtained.

Claims (2)

[Claims] 1. General formula (I): [In the formula, R ¹ , R ² and R ³ are the same or different and each represent a hydrogen atom, or an alkyl group or an alkoxy group which may have a substituent, and n represents an integer of 1 to 5. ] The butadiene derivative represented by this. 2. An electrophotographic photoreceptor comprising a conductive substrate and a photosensitive layer containing a butadiene derivative represented by the general formula (I).