JPH02134643A - Electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To obtain an electrophotographic sensitive body capable of retarding fluctuation of a light part potential and a dark part potential in a stage of forming continuous picture image by repetitive charge and exposure by incorporating a specified compd. into a photosensitive layer. CONSTITUTION:A compd. expressed by the formula I is incorporated into a photosensitive layer. In the formula I, each Ar1 and Ar2 is an aryl or heterocyclic group which may have a substituent, wherein at least one of Ar1 and Ar2 has a residue expressed by the formula II; each R1-R3 is an H atom, an alkyl group, etc. In the formula II, each R2 and R3 is an H atom, a (substituted) alkyl or (substituted)aryl group, etc., wherein R2 and R3 may form a 5- to 7-membered ring together with an N atom to be bonded. Thus, an electrophotographic sensitive body having high sensitivity and retarded fluctuation of a light part potential and a dark part potential when it is charged and exposed repeatedly, is obtd.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to electrophotographic photoreceptors, and more particularly to electrophotographic photoreceptors having a low molecular weight organic photoconductor that provides improved electrophotographic properties.

[Prior Art] In recent years, many electrophotographic photoreceptors using organic compounds as photoconductive materials have been developed.

Most of those that have been put to practical use have a form in which the photoconductor is functionally separated into a charge generating material and a charge transporting material.

However, one major drawback of these electrophotographic photoreceptors has been that they generally have lower durability than inorganic electrophotographic photoreceptors.

Durability is broadly divided into durability of electrophotographic physical properties such as sensitivity, residual potential, charging ability, and image blur, and mechanical durability such as wear and scratches on the photoreceptor surface due to rubbing. Regarding durability in terms of physical properties, it is known that the main cause is deterioration of the charge transporting material contained in the photoreceptor surface layer due to ozone, NOx, etc. generated by corona discharge and light irradiation.

In addition, as an organic charge transport material, US Pat. No. 4150
hydrazone compounds described in US Pat. No. 987, etc., triazolepyrazoline compounds described in US Pat.
No. 2, JP-A No. 61-295558 and JP-A No. 6
Many proposals have been made, such as the henzidine compound described in JP-A No. 2-201447, and the diphenylmethane compound described in JP-A-52-4242, etc., and although the above-mentioned durability has been considerably improved, it is still insufficient. The current situation is that it is impossible to say.

[The problem that the invention seeks to solve! fi] It is an object of the present invention to provide a new organic photoconductor and to provide an electrophotographic photoreceptor which eliminates the above-mentioned drawbacks or disadvantages.

[Means for Solving the Problems, Effects] The present invention provides an electrophotographic photoreceptor in which a photosensitive layer is laminated on a conductive support, wherein the photosensitive layer contains a compound represented by the following general formula. Consists of a photoreceptor.

In the formula, Arl and Ar2 represent an aryl group or a heterocyclic group which may have a substituent, and at least one of Ar1 and Ar2 is an alkyl group or an aryl group which may have a substituent.

represents an aralkyl group or a heterocyclic group, and R2 and R3
may form a 5- to 7-membered ring together with the bonded nitrogen atom), and R1 is a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom, a cyano group, a nitro group, an acyl group, or a trifluoromethyl group. represent.

Specifically, in Arl and Ar2, examples of the aryl group include groups such as benzene, naphthalene, and anthracene, and examples of the heterocyclic group include groups such as pyrrole, oxazole, pyridine, quinoline, and carbazole;
In R1, the alkyl group is a group such as methyl, ethyl, propyl, etc., the aralkyl group is a group such as benzyl or phenethyl, the alkoxy group is a group such as methoxy, ethoxy, etc., and the halogen atom is a fluorine atom, a chlorine atom, Groups such as bromine atoms, acyl groups include acetyl,
Examples include groups such as butyryl.

Furthermore, examples of the substituent of the above group include halogen atoms such as fluorine atom, chlorine atom, and bromine atom.

Alkyl groups such as methyl, ethyl and propyl, flukoxy groups such as methoxy and ethoxy, benzenenaphthalene,
Examples include aryl groups such as anthracene, and heterocyclic groups such as pyrrole 4 pyridine and carbazole.

Further, in R2 and R3, the alkyl group is a group such as methyl, ethyl, propyl, etc., the aryl group is a group such as benzene, naphthalene, anthracene, etc., and the aralkyl group is benzyl.

Examples of groups such as phenethyl and heterocyclic groups include groups such as pyrrolepyridine, quinoline, and carbazole, and further examples of 5- to 7-membered rings include acridine rings and carbazole rings.

Examples of substituents that the above group may have include methylethyl,
Alkyl groups such as propyl, aryl groups such as benzenaphthalene and anthracene.

Examples include heterocyclic groups such as pyrrole, pyridine, and carbazole, aralkyl groups such as benzyl and phenethyl, alkoxy groups such as methoxy and ethoxy, and halogen atoms such as fluorine, chlorine, and bromine. It's okay.

Below, regarding the compound shown in the above-mentioned formation, E.

List examples of tables.

Compound Example (1) Compound Example (2) Compound Example (3) Compound Example Compound Example (5) Compound Example (6) Compound Example (1 Compound Example (13) Compound Example (14) Compound Example (15) Compound Example (1) Compound Example Compound Example (8) Compound Example Compound Example (10) Compound Example (11) Compound Example (17) Compound Example (18) Compound Example (19) Compound Example (20) Compound Example (21) Compound Example (22) Compound Example (23) Compound Example (24) Compound Example (25) Shi! Compound Example (26) Compound Example (31) Compound Example (32) Compound Example (33) Compound Example (34) Compound Example (35) Compound Example (27) ) Compound Example (28) Compound Example (29) Compound Example (30) Compound Example (36) Compound Example (37) Compound Example (38) Compound Example (39) Compound Example (40) Compound Example (41) Compound Example (45) ) Example compound (42) Example compound (46) Example compound (43) Example compound (47) Example compound (44) Synthesis example (synthesis of example compound (39)) Nitration of m-terphenyl by a known method, followed by 5.OOg (19.1 mmol) obtained by reduction was dissolved in 50 ml of anhydrous tetrahydrofuran, and while stirring at room temperature, 4.60 g (114 mmol) of oily sodium hydride (content 60%)
, 6 mmol) was added slowly. After the addition was completed, after further stirring at room temperature for 15 minutes, 21.69 g of methyl iodide was added.
(152.8 mmol) was slowly added dropwise and heated and stirred for 3 hours. After the completion of the reaction, the reaction solution was poured into water, the precipitated crystals were washed with methanol, and further purified by recrystallization, yielding 4.61 g of the target compound. I got it.

Elemental analysis calculated value (%) Actual value (%) CB3.50 83.51 8 7.65 7.6O N 8.85 8.89 Compounds other than those on the synthesis side are generally synthesized using the same method. .

In a preferred embodiment of the present invention, a compound represented by the above general formula is used as a charge transport material in an electrophotographic photoreceptor in which the photosensitive layer is functionally separated into a charge generation layer and a charge transport layer.

The charge transport layer in the present invention is a compound represented by the general formula □
It is preferable to form droplets by dissolving a binder and a binder in a suitable solvent, applying the droplets, and drying the droplets.

Examples of the binder used here include polyarylate,
Polysulfone, polyamide, acrylic resin, acrylonitrile resin, methacrylic resin, vinyl chloride resin, vinyl acetate resin, phenolic resin, epoxy resin, polyester, alkyd resin, polycarbonate, polyurethane or copolymer 1 such as styrene-butadiene copolymer, styrene-acrylonitrile copolymers, styrene-maleic acid copolymers, and the like.

In addition to such insulating polymers, organic photoconductive polymers such as polyvinylcarbazole, polyvinylanthracene, and polyvinylpyrene can also be used.

The blending ratio of this binder and the charge transport material of the present invention is preferably 10 to 500 parts by weight of the charge transport material per 100 parts by weight of the binder.

The charge transport layer is electrically connected to the charge generation layer below and has the function of receiving charge carriers injected from the charge generation layer in the presence of an electric field and transporting these charge carriers to the surface. ing. In this case, this charge transport layer may be laminated on top of the charge generation layer, or may be laminated below it.However, the charge transport layer may be laminated on the charge generation layer. is desirable.

This charge transport layer has a limit in its ability to transport charge carriers, so it cannot be made thicker than necessary, although it is generally 5 to 40 gm.

The preferred range is 10-30 ILm.

The organic solvent used to form such a charge transport layer varies depending on the type of binder used, and is preferably selected from those that do not dissolve the charge generation layer or underlying subbing layer. Examples of organic solvents include methanol,
Alcohols such as ethanol and isopropanol; ketones such as acetone, methyl ethyl ketone, and cyclohexanone; amides such as N,N-dimethylformamide and N,N-dimethylacetamide; sulfoxides such as dimethyl sulfoxide; tetrahydrofuran, dioxane, and ethylene. Ethers such as glycol monomethyl ether, esters such as methyl acetate and ethyl acetate, aliphatic halogenated hydrocarbons such as methylene chloride, dichloroethylene, carbon tetrachloride, and trichloroethylene, or benzene, toluene, xylene, chlorobenzene, and dichlorobenzene. Aromatic compounds such as these can be used.

Coating methods include dip coating, spray coating, spinner coating, bead coating,
This can be carried out using a coating method such as a Mayer bar coating method, a blade coating method, a roller coating method, or a curtain coating method. Drying is preferably carried out by drying to the touch at room temperature, followed by heat drying. Heat drying is generally preferably carried out at a temperature of 30 to 200°C for 5 minutes to 2 hours, either stationary or under ventilation. .

The charge transport layer of the present invention may contain various additives, such as stabilizers such as diphenyl, m-terphenyl, and dibutyl phthalate, silicone oil, grafted silicone polymers, and various fluorocarbons. surface lubricants, potential stabilizers such as dicyanovinyl compounds and carbazole derivatives, and antioxidants such as β-carotene, Ni complexes, and 1,4-diazabicyclo[2,2,2]octane.

The charge generation layer in the present invention includes an inorganic charge generation material such as selenium, selenium-tellurium, amorphous silicone, etc.
Cationic dyes such as pyrylium dyes, thiapyrylium dyes, azulenium dyes, thiacyanine dyes, and quinocyanine dyes.

Organic charge-generating substances such as sulfherylium salt dyes, phthalocyanine pigments, anthorone pigments, dibenzpyrenequinone pigments, polycyclic iron pigments such as pyranthrone pigments, indigo pigments, quinacridone pigments, and azo pigments. Materials selected from the following can be used alone or in combination as a vapor deposited layer or a coating layer.

Among the above-mentioned charge-generating substances, there are a wide variety of azo pigments in particular, and a typical structural example of an azo pigment that is highly effective against # will be described below.

The general formula of the azo pigment is shown below, with A as the central skeleton and Cp as the coupler part, where n is 1 or 2. Specific examples are given below.

A-+N■N-0p) n Specific examples of A include (R: hydrogen atom, chlorine atom, methoxy group) (R: hydrogen atom, cyano group) (R: hydrogen atom, cyano group) (x: oxygen Atom, Sulfur atom R: Hydrogen atom (x: Oxygen atom.

sulfur atom) methyl group, chlorine atom) (x: oxygen atom.

sulfur atom) Rz (x: oxygen atom, sulfur atom Rz2 hydrogen atom.

methyl group, chlorine atom) (R :Hydrogen atom, methyl group) (X d -OH co, oxygen atom.

sulfur atom, ll5O2) (Rz Rz :Hydrogen atom, Methyl group.

chlorine atoms etc. :Hydrogen atom, Methyl group.

Be◇ Wandering Pemo) (x: oxygen atom, sulfur atom) (X :Oxygen atom, sulfur atom) (x: oxygen atom, sulfur atom) l or 2) 2Hs 1@-CH-N-N-C)I-@-(R: methyl group, Ethyl group.

propyl group Such) A-21 Nawateha (X R’ (R :Hydrogen atom, methyl group) Child, halogen atom, alkoxy group, a Lukyl group, nitro group, etc.) ] n Also, as a specific example of Cp, (R: hydrogen atom, halogen atom.

Alkoxy group, alkyl group, nitro group, etc. (R: alkyl group, aryl group, etc.) (R,, R dihydrogen atom, halogen atom alkoxy group,
Examples include an alkyl group, a nitro group, etc. (n: 1 or 2).

The central skeleton A and the coupler Cp form a pigment serving as a charge-generating substance by appropriate combination.

The charge generation layer can be formed by dispersing the charge generation substance described above in a suitable binder and coating it on a support, or by forming a vapor deposited film using a vacuum evaporation device. .

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

Preferably polyvinyl butyral, polyarylate (polycondensate of bisphenol A and phthalic acid, etc.), polycarbonate, polyester, phenoxy resin, polyvinyl acetate, acrylic resin, polyacrylamide, polyamide, polyvinylpyridine, cellulose resin, urethane resin, epoxy resin, casein, polyvinyl alcohol,
Examples include polyvinylpyrrolidone.

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

Organic solvents used during coating include alcohols such as methanol, ethanol, and isopropanol, ketones such as acetone, methyl ethyl ketone, and cyclohexanone, and amides such as N,N-dimethylformamide and N,N-dimethyl 7cetamide. sulfoxides such as dimethyl sulfoxide, ethers such as tetrahydrofuran, dioxane, and ethylene glycol monomethyl ether, esters such as methyl acetate and ethyl acetate, and fats such as chloroform, methylene chloride, dichloroethylene, carbon tetrachloride, and trichloroethylene. Group halogenated hydrocarbons or aromatic compounds such as benzene, toluene, xylene, monochlorobenzene, dichlorobenzene, etc. can be used.

Coating methods include dip coating, spray coating, spinner coating, bead coating,
This can be carried out using a coating method such as a Mayer coating method, a blade coating method, a roller coating method, or a curtain coating method.

Drying is preferably carried out by drying to the touch at room temperature and then heating. Drying by heating is generally carried out at 30 to 200°C.
It is preferable to carry out the process at a temperature of 5 minutes to 2 hours, either stationary or under ventilation.

The charge generation layer contains as much of the organic photoconductor as possible in order to obtain sufficient absorbance and contains a thin film layer, e.g. 5 lm or less, preferably 0.01=
A thin film layer having a thickness of 1 pm is desirable.

A photosensitive layer having such a laminated structure of a charge generation layer and a charge transport layer is provided on a support having a conductive layer. Examples of the support having a conductive layer include those whose support itself is conductive, such as aluminum, aluminum alloy, copper,
Zinc, stainless steel, vanadium, molybdenum, chromium,
Plastics that can use titanium, nickel, indium, gold, platinum, etc., and have a layer formed by vacuum evaporation of aluminum, aluminum alloys, indium chloride, tin oxide, indium oxide-tin oxide alloys, etc. conductive particles (e.g., aluminum powder, titanium oxide, tin oxide,
Supports such as zinc oxide, carbon black, silver particles, etc.) coated on plastic or the above-mentioned conductive support with a suitable binder, supports made of plastic or paper impregnated with conductive particles, plastics containing conductive polymers, etc. can be used.

A subbing layer having barrier and adhesive functions can also be provided between the conductive support and the photosensitive layer.

The undercoat layer is formed from casein, polyvinyl alcohol, nitrocellulose, ethylene-acrylic acid copolymer, polyamide (nylon 6, nylon 66, nylon 610, copolymerized nylon, alkoxymethylated nylon, etc.), polyurethane, gelatin, aluminum oxide, etc. can.

The thickness of the undercoat layer is 0.1 to 5 ILm, preferably 0.5 to 5 ILm.
3 m is appropriate.

When using a photoreceptor in which a conductive support, a charge generation layer, and a charge transport layer are laminated in this order, the charge transport compound in the present invention has hole transport properties, so it is necessary to negatively charge the surface of the charge transport layer. When exposed to light after being charged, holes generated in the charge generation layer in the exposed area are injected into the charge transport layer, and then reach the surface and neutralize the negative charge, resulting in attenuation of the surface potential and the gap between the exposed area and the unexposed area. Electrostatic contrast occurs.

During development, it is necessary to use positively charged toner.

In another specific example of the present invention, the above-mentioned azo pigment or the pyrylium dyes, thiapyrylium dyes, selenapyrylium dyes, and benzene dyes disclosed in U.S. Pat. Pyrylium dye, benzothiapyrylium dye,
Photoconductive pigments and dyes such as naphthopyryllium dyes and naphthothiapyrylium dyes can also be used as sensitizers.

In another specific example, a eutectic complex of a biryllium dye and an electrically insulating polymer having a fullkylidene diarylene moiety, such as disclosed in US Pat. No. 3,684,502, can be used as a sensitizer. This eutectic complex is, for example, 4-[4-bis(2-chloroethyl)aminophenyl]
-2,6-Cyphenylthiapyrylium perchlorate and poly(4,4°-isopropylidene diphenylene carbonate) are mixed in a halogenated hydrocarbon solvent such as dichloromethane, chloroform, carbon tetrachloride, 1°1-dichloroethane, 1° .2-dichloroethane, 1.1.2-trichloroethane, chlorobenzenebromobenzene, 1.2-
After dissolving in dichlorobenzene or the like, a nonpolar solvent 1 such as hexane, octane, decane, 2,2,4-trimethylbenzene, ligroin, etc. is added thereto to obtain a particulate eutectic complex.

The electrophotographic photoreceptor in this specific example includes a styrene-butadiene copolymer and a silicone resin.

Vinyl resin, vinylidene chloride-7-crylonitrile copolymer, styrene-7-crylonitrile copolymer, vinyl acetate-vinyl chloride copolymer polyvinyl butyral, polymethyl methacrylate, poly-N-butyl methacrylate, polyesters, cellulose esters, etc. as binders. It can contain.

The electrophotographic photoreceptor of the present invention can be used not only in electrophotographic copying machines but also in a wide range of electrophotographic applications such as laser beam printers, CRT printers, and electrophotographic plate making systems.

The electrophotographic photoreceptor of the present invention has the advantage of high sensitivity and small fluctuations in bright area potential and dark area potential when repeatedly charged and exposed.

[Example] Example 1 5 g of a disazo pigment represented by the following structural formula was mixed with butyral resin (
butyralization degree 63 mol%) 2g cyclohexanone l
A coating solution was prepared by dispersing the solution in a sand mill for 24 hours together with the solution dissolved in OOMI.

This coating solution was applied onto an aluminum sheet with a dry film N of 0.2 #Lm.
A charge generation layer was formed by coating with a Maya bar so that the charge generation layer was formed.

Next, the log of Compound Example (39) as a charge transport material and 10 g of polycarbonate (average molecular weight 20,000) were dissolved in 70 g of chlorobenzene, and this solution was applied onto the charge generation layer using a Mayer bar, and the dried film was coated. A charge transport layer having a thickness of 201 Lm was formed to produce an electrophotographic photoreceptor.

The electrophotographic photoreceptor thus prepared was statically charged with corona at 15 KV using an electrostatic copying paper tester Model 1-3P-428 manufactured by Kawaguchi Denki Co., Ltd., and after being held in a dark place for 1 second, the illuminance was set to 20 Lux. It was exposed to light and the charging characteristics were investigated.

As for charging characteristics, the surface potential (Vo) and the exposure ffi (E 1/2) required to attenuate the potential (V]) by 1/2 when dark decayed for 1 second were measured.

Furthermore, in order to measure the fluctuations in dark area potential and bright area potential during repeated use, the electrophotographic photoreceptor prepared in this example was attached to the photosensitive drum cylinder of a Canon PPC copier NP-3525. , 5,000 copies were made with the same machine, and the dark area potential (initial and after 5,000 copies) was
Variations in Vo ) and light area potential (VL) were measured.

a-o, initial (7) VD to VL c each/r -700
The voltage was set to 200v.

For comparison, a similar electrophotographic photoreceptor was prepared using a compound having the structure shown below in place of the charge transport material used in Example 1 as a charge transport material, and the electrophotographic properties were similarly measured.

(83G), LNNO2-CH+N(CHi)z results are shown.

Example 1 -700 -690 1.9 Comparative example, -
715-6208,9 V5 V Example I Vo -700-675VL -
200-215 Comparative Example Vo -700-610 VL -200-285 As is clear from the above results, when the charge transport material specified in the present invention is used, it has good sensitivity and there is no potential fluctuation during durability. It turns out that there are few.

Examples 2 to 15 In each of these Examples, charge transport compound examples (39) used in Example 1 were replaced with compound examples (5), (7), and (8).
, (12), (13).

(14), (17), (20), (23), (25),
Using (31), (34), (40) and (41),
In addition, an electrophotographic photoreceptor was prepared using a pigment having the following structural formula as a charge-generating substance, and the other conditions were the same as in Example 1.

Initial 680 2.0 685 1.7 710 2.0 700 1.8 715 1.7 725 2.1 6952.1 725 2.0 720 1.8 710 1.7 700 1.4 After 5,000 sheets The electrophotographic properties of each photoreceptor were measured in the same manner as in Example 1. Show the results.

1 , 9 2 , 2 1.8 Example 16 An ammonia aqueous solution of casein (11.2 g of casein, 1 g of 28% ammonia water, 222 m of water) was coated on an aluminum cylinder using a blade coating method, and a dry film thickness of 1 ml was applied. A subbing layer of m was formed.

Next, a charge generating substance Log represented by the following structural formula, 5 g of butyral resin (butyralization degree: 63 mol %), and 200 g of cyclohexanone were dispersed for 48 hours using a ball mill disperser. This dispersion was applied onto the previously formed undercoat layer by a blade coating method to form a charge generation layer having a dry film thickness of 0.15 lm.

Next, compound example (29) is Log, polymethyl methacrylate (average molecular weight 50,000) log is chlorobenzene 70
g and applied to L of the previously formed charge generation layer by a blade coating method to form a charge transport layer having a dry film thickness of 19 lm.

A corona discharge of 15 KV was applied to the electrophotographic photoreceptor thus prepared. The surface potential at this time was measured (initial potential VO).Furthermore, the surface potential was measured after this photoreceptor was left in a dark place for 1 second.

The sensitivity is defined as the exposure 1 (El/2, microjoule/cm2) required to attenuate the lower level V1 to 1/2 after dark decay.
) was evaluated by measuring.

At this time, the light source was a gallium/aluminum/propylene ternary semiconductor laser (output: 5 mw, oscillation wavelength: 780 nm).
m) was used. Show the results.

Vg knee 740V Vl knee 735Vel
/2: 2.7 microjoules/cm 2 Next, the photoreceptor was placed in a laser beam printer (manufactured by Canon ■, LBP-CX), which is a reversal development type electrophotographic printer equipped with the same semiconductor laser. An actual image forming test was conducted by setting the photoreceptor in place of the LBP-CX photoreceptor.

The conditions are: -700V surface potential after -order charging.

Surface potential after image exposure knee 150V (exposure amount 2.0 microjoules/cm2), transfer potential: +700V, developer polarity: negative polarity, process speed = 50mm/see,
Development conditions (development bias) Knee 450V, image exposure scanning method: image scan, - exposure before next charging = 50 u
The entire surface was exposed to red light at x, sec, and image formation was carried out by line scanning a laser beam in accordance with character and image signals, and good prints were obtained for both characters and images. Further, when 3,000 images were printed continuously, stable and good prints were obtained from the initial stage up to 3,000 sheets.

Example 17 3 g of 4-(4-dimethylaminophenyl)-2,6-diphenylthi7virylium perchlorate and compound example (
19) to 5 g of polyester (Polyester Adhesive 49000, manufactured by DuPont) notluene (50
)-Dioxane (50 parts by weight) was mixed with 100 mJL of solution and dispersed in a ball mill for 6 hours. This dispersion was applied onto an aluminum sheet using a Mayer bar so that the film thickness after dry explosion was 15 pm.

The electrophotographic properties of the electrophotographic photoreceptor thus prepared were measured in the same manner as in Example 1. Show the results.

Vo knee 730V Vl knee 725Vel/2
:4.7 ux, sec 惺-1 Vo Knee 700V VL Knee 200Vi1 竖亙入丑Vo Knee 680V VL, Knee 215V Example 18 4-(4-dimethylaminophenyl)-2,6-siphenylthiapyrylium Perchlorate 3g and poly(4,
4°-Isopropylidene diphenylene carbonate))3
After fully dissolving g in 200rnl of dichloromethane,
Toluene roomJl was added to precipitate the eutectic complex.

After filtering this precipitate, dichloromethane was added to redissolve it, and then 7100 ml of n-hexane was added to this solution to obtain a precipitate of a eutectic complex.

5 g of this eutectic complex was added to 95 mJl of a methanol solution containing 2 g of polyvinyl butyral, and dispersed for 6 hours using a ball mill disperser. This dispersion was applied onto an aluminum plate having a casein layer using a Mayer bar so that the film thickness after drying was 0.4 #Lm to form a charge generation layer.

Next, a cover layer of a charge transport layer was formed in the same manner as in Example 1 except that Compound Example (43) was used on the charge generation layer.

The electrophotographic properties of the thus produced electrophotographic photoreceptor were measured in the same manner as in Example 1. Show the results.

vo knee 730V Vl knee 710Vel
/2: 3.7jLux, sec first - Kazutomo Vo: -700V VL Knee 20
0V 1st diameter Vo Knee 685V VL Knee 215V
Example 19 An ammonia aqueous solution of casein (described above) was coated on an aluminum plate using a Meyer bar to form a subbing layer with a dry film thickness of Igm. The charge transport layer and charge generation layer of Example 12 were sequentially laminated thereon, and an electrophotographic photoreceptor was prepared in exactly the same manner as in Example 12, except that the single layer structure was different, and the charging properties were the same as in Example 12. was measured. However, the charging polarity was set to 10.

Show the results.

VO: +710V VT: +705VEl/2
: 3.4jLux, see Example 20 Soluble nylon (6-86-610-12
A 5% methanol solution of a quaternary nylon copolymer) was applied to form a subbing layer having a dry thickness of 0.51 Lm.

Next, 5 g of the pigment having the following structural formula was added to 95 g of tetrahydrofuran.
It was dispersed in mJL for 200 hours using a sand mill.

vo knee 710V V, knee 685V
El/2: 3.9 Jlux, sec [Effects of the Invention] The electrophotographic photoreceptor containing the specific compound of the present invention as a charge transporting substance has high sensitivity and repeating band 'Il
! It is an electrophotographic photoreceptor with excellent durability, with small fluctuations in bright area potential and dark area potential during continuous image formation by exposure.

Next, a solution prepared by dissolving 5 g of Compound Example (18) and 10 g of bisphenol Z type polycarbonate (viscosity average molecular weight 30,000) in 30 mjL of chlorobenzene was added to the dispersion prepared above, and the mixture was further dispersed for 2 hours using a sand mill. This dispersion was applied onto the previously formed subbing layer using a Mayer bar so that the film thickness after drying would be 20 gm, and then dried.

The electrophotographic properties of the electrophotographic photoreceptor thus prepared were measured in the same manner as in Example 1. Show the results.

Claims (1)

[Scope of Claims] 1. An electrophotographic photoreceptor comprising a photosensitive layer laminated on a conductive support, wherein the photosensitive layer contains a compound represented by the following general formula. General formula ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ In the formula, Ar_1 and Ar_2 represent an aryl group or a heterocyclic group that may have a substituent, and Ar_1, Ar_
At least one of 2 is a ▲ mathematical formula, chemical formula, table, etc. ▼ group (in the formula, R_2 and R_3 are a hydrogen atom, an alkyl group, an aryl group, an aralkyl group, or a heterocyclic group that may have a substituent) and R_2 and R_3 together with the bonding nitrogen atom are 5 to 7
R_1 represents a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom, a cyano group, a nitro group, an acyl group, or a trifluoromethyl group.