JPH02156247A - Electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To enhance sensitivity and durability by incorporating a specified fulvene compound in a photosensitive layer. CONSTITUTION:The photosensitive layer formed on a conductive substrate conetains one of the fulvene compounds represented by formula I in which each of R1 and R2 is alkyl, aralkyl, or aryl; R3 is H, alkyl, alkoxy, or halogen; R4 is H, alkyl, aralkyl, or aryl; each of R5-R8 is H, alkyl, or aryl, thus permit ting sensitivity to the visible light, charge holding ability, and surface strength to be enhanced.

Description

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

[Prior Art] Various organic photoconductive polymers, including polyvinylcarbazole, have been proposed as photoconductive materials for use in electrophotographic photoreceptors, but these polymers have a disadvantage in comparison to inorganic photoconductive materials. Although it is excellent in terms of film formability, lightness, etc., it has been difficult to put it into practical use until now because sufficient film formability has not yet been obtained, and sensitivity and
#This is because it is inferior to inorganic photoconductive materials in terms of durability and stability against environmental changes.

In addition, hydrazone compounds disclosed in U.S. Pat. No. 4,150,987, triarylpyrazoline compounds disclosed in U.S. Pat.
9-styrylanthracene compounds described in JP-A-94828, JP-A-51-94829, etc.;
Low-molecular organic photoconductors such as benzylidene compounds described in JP-A-2-128373 and JP-A-55-161247 have been proposed. These low-molecular-weight organic photoconductors have been able to overcome the film-forming problems that had been a problem in the field of organic photoconductive polymers by appropriately selecting the binder used, but the sensitivity It cannot be said that it is sufficient in this respect.

For this reason, in recent years, a laminated structure in which the photosensitive layer is functionally separated into a charge generation layer and a charge transport layer has been proposed. Electrophotographic photoreceptors using this laminated structure as a photosensitive layer can now be improved in terms of sensitivity to visible light, charge retention, surface strength, and the like.

Such an electrophotographic photoreceptor is disclosed in, for example, US Pat. No. 383
It is disclosed in the specification No. 7851, the specification No. 3871882, etc.

However, electrophotographic photoreceptors that use conventional low-molecular organic photoconductors in the charge transport layer do not necessarily have sufficient sensitivity and characteristics, and when repeatedly charged and exposed, the bright area potential and dark area potential change. There are areas that need improvement.

[Problems to be Solved by the Invention] An object of the present invention is to provide an electrophotographic photoreceptor that eliminates the above-mentioned drawbacks or disadvantages, to provide a novel organic photoconductor, and to provide a charge generation layer and a charge transport layer. The object of the present invention is to provide a novel charge transport material in a laminated photosensitive layer with functionally separated functions.

[Means for Solving the Problems 1 Effect] The present invention provides an electrophotographic photoreceptor in which a photosensitive layer is laminated on a conductive support, wherein the photosensitive layer contains a fulvene compound represented by the following general formula. Consists of a photoreceptor.

In the formula, R1 and R2 are the same or different and represent an alkyl group, an aralkyl group, or an aromatic ring group, R3 represents a hydrogen atom, an alkyl group, an alkoxy group, or a halogen atom, and R4 represents a hydrogen atom, an alkyl group, an aralkyl group, or an aromatic group. R5, R6, R7 and R8 are the same or different and represent a hydrogen atom, an alkyl group or an aromatic ring group, and the 7ralkyl group or aromatic ring group of R, R2 and R4 may have a substituent. good.

Specifically, in R1 and R2, the alkyl group is a group such as methyl, ethyl, propyl, etc., and the aralkyl group is a group such as benzyl, phenethyl, etc.

Examples of aromatic ring groups include groups such as phenyl and naphthyl; in R3, examples of an alkyl group include a group such as methylethyl; an alkoxy group includes a group such as methoxyethoxy; and a halogen atom includes a chlorine atom, a bromine atom, an iodine atom, etc. In R4, the alkyl group includes groups such as methyl and ethyl, the aralkyl group includes groups such as benzyl and phenethyl, and the aromatic ring group includes phenyl and naphthyl, and in R5-R8, the alkyl group includes methyl, ethyl, Groups such as isopropyl and aromatic ring groups include phenyl and the like.

Further, in R,, R2 and R4, examples of substituents that the aralkyl group and the aromatic ring group may have include alkyl groups such as methyl and ethyl, alkoxy groups such as methoxy and ethoxy, and chlorine atoms.

Examples include halogen atoms such as bromine atoms and iodine atoms, and nitro groups.

Representative examples of the fulvene compound represented by the general formula are listed below.

Compound Example (1) Compound Example (2) Compound Example (3) Compound Example Compound Example (5) Compound Example (6) Compound Example (7) Compound Example (11) Compound Example (l 2) Compound Example (13) Compound Example (1 I3 Compound Example Compound Example (9) Compound Example (10) Compound Example (15) Compound Example (16) Compound Example (17) Toe CHB Compound Example (18) Compound Example (19) Compound Example (23) Compound Example (20) Compound Example (24) Compound Example (21) Compound Example (25) Compound Example (22) Compound Example (26) N 2.24 2.22 Compound Example (27) Synthesis Example (Synthesis of Compound Example (8) ) 1.2,3.4-Tetraphenylcyclopentadiene is reacted with a base such as methoxy sodium to obtain a carbanion, which is condensed with 4-diphenylaminobenzaldehyde to obtain compound example (8) of the target compound.
C4H-3J3N was obtained.

Elemental analysis theoretical value (%) 92.12 5 , 64 Actual value (%) 92.10 5.68 In a preferred embodiment of the present invention, an electrophotographic photoreceptor in which the photosensitive layer is functionally separated into a charge generation layer and a charge transport layer is used. A fullpene compound represented by the above general formula is used as the charge transport material.

The charge transport layer in the present invention is preferably formed by applying a solution of the fulvene compound represented by the above general formula and a binder dissolved in a suitable solvent and drying the solution.

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 For example, styrene-butadiene copolymer, styrene-acrylonitrile copolymer , styrene-
Mention may be made, for example, of maleic acid copolymers.

In addition to such insulating polymers, organic photoconductive polymers such as polyhinylcarhesol, 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 electric 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. have. In this case, this charge transport layer may be laminated on the charge generation layer E or may be laminated below it. However, the charge transport layer may be laminated on the charge generation layer E. is desirable.

This charge transport layer has a limit to its ability to transport charge carriers, so it cannot be made thicker than necessary.
- 5 to 40 gm for auctions, but the preferred range is lO
~30 m.

The organic solvent used to form such a charge transport layer varies depending on the type of binder used, or is preferably selected from those that do not dissolve the charge generation layer or underlying subbing layer. Examples of solvents include alcohols such as methanol, ethanol, and isopropanol, ketones such as acetone, methyl ethyl ketone, and cyclohexanone, amides such as N,N-dimethylformamide, N,N-dimethylacetamide, and dimethyl sulfoxide. sulfoxides, ethers such as tetrahydrofuran, dioxane, ethylene glycol methyl ether, esters such as methyl acetate, ethyl acetate,
Aliphatic halogenated hydrocarbons such as methylene chloride, dichloroethylene, carbon tetrachloride, and trichlorethylene, and aromatic compounds such as benzene, toluene, xylene, chlorobenzene, and dichlorobenzene 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. For drying, it is preferable to dry to the touch at room temperature and then heat dry.For auctions, heat drying can be carried out at a temperature of 30 to 200°C for 5 minutes to 2 hours, either stationary or under ventilation. preferable.

The charge transport layer of the present invention may contain various additives, such as plasticizers such as diphenyl, m-terphenyl, and dibutyl phthalate, silicone oil, grafted silicone polymers, and various fluorocarbons. Examples include 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 substance such as selenium, selenium-tellurium, amorphous silicone, etc.
Cationic dyes such as pyrylium dyes, thiapyrylium dyes, azulenium dyes, thiacyanine dyes, and quinodi7ine dyes.

From charge-generating substances such as polycyclic pigments such as squbarium salt dyes, phthalocyanine pigments and anthrone pigments, dibenzpyrenequinone pigments, and pyranthrone pigments, indigo pigments, quinacridone pigments, and azo pigments. The selected materials can be used alone or in combination as a vaporized M layer or a coating layer.

Among the above-mentioned charge-generating substances, there are a wide variety of azo pigments in particular, and typical structural examples of particularly effective azo pigments will be described below.

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

A-(N-N-Cp)n As a specific example of A, (R: hydrogen atom, chlorine atom, methoxy group) (R: hydrogen atom.

cyano group) (R: hydrogen atom, cyan group) (x: oxygen atom.

sulfur atom) (x: oxygen atom.

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

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

methyl group) (x: Exploration CH,.

oxygen atom.

sulfur atom.

-SOΣ) (R1, R: l: hydrogen atom, methyl group, chlorine atom, etc. :Hydrogen atom.

Mail chill group.

(Lesson 9) Also, as a specific example of Cp, (x: oxygen atom, sulfur atom) (R: hydrogen atom, halogen atom, 7 Ruco xy group, alkyl group, Nitro group etc. (x: oxygen atom.

sulfur atom) n: l or 2) CλHr １＠－C）I－N　－N鳳C）I－＠－(R： methyl group, ethyl group, propyl group Such) Ma -@-N-@- [R: Alkyl group, ◇ R.

(Ro: Hydrogen source (R: hydrogen atom.

methyl group) Child, halogen atom.

(R: alkyl group, aryl group, etc.) R (R1, R2: hydrogen atom, halogen atom, alkoxy group,
Examples include alkyl groups, nitro groups, etc. (n:l or 2).

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

The charge-generating layer can be formed by dispersing the above-mentioned charge-generating substance in a suitable binder and coating it on the support, or by forming a vapor-deposited film using a vacuum N deposition device. Can be formed.

The binder can be selected from a wide variety of insulating resins and organic photoconductive polymers such as poly-N-vinylcarhesol, 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 P
Examples include A fat, epoxy resin, casein, polyvinyl alcohol, and 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-dimethylacetamide. , sulfoxides such as dimethyl sulfoxide, ethers such as tetrahydrofuran, dioxane, and ethylene glycol monomethyl ether, esters such as methyl acetate and ethyl acetate, and aliphatics such as chloroform, methylene chloride, dichloroethylene, carbon tetrachloride, and trichloroethylene. Halogenated hydrocarbons or aromatic compounds such as benzene, toluene, xylene, monochlorobenzene, and dichlorobenzene 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.

For drying, it is preferable to dry to the touch at room temperature and then heat dry.Heat drying is carried out at -30 to 200°C for boat fishing.
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 a thin film layer, e.g. Tile m or less, preferably 0.01”1
A thin film layer having a film thickness of gm 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 oxide, tin oxide, indium oxide-tin oxide alloys, etc. For example, polyethylene, polypropylene, polyvinyl oxide, polyethylene terephthalate, acrylic resin, polyfluorinated ethylene, etc.), conductive particles (for example, aluminum powder, titanium oxide, tin oxide,
(zinc oxide, carbon black, silver particles, etc.) together with a transparent binder on a plastic or conductive support, a support in which plastic or paper is impregnated with conductive particles, and a plastic with a conductive polymer. 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 subbing layer is casein and polyvinyl alcohol.

Nitrocellulose, ethylene-acrylic acid copolymer,
Polyamide (nylon 6, nylon 66, nylon 61
0, copolymerized nylon, alkoxymethylated nylon, etc.), polyurethane, gelatin aluminum oxide, etc.

The thickness of the subbing layer is 0.1 to 5 μm, preferably 0.5 to 3 μm.
The ending m is appropriate.

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. Photoconductive pigments and dyes such as pyrylium dye book 4, benzothiapyryllium dye, naphthopyryllium dye, and naphthothiapyrylium dye can also be used as sensitizers.

In another specific example, a eutectic complex of a pyrylium dye and an electrically insulating polymer having an alkylidene diarylene moiety, such as disclosed in US Pat. No. 3,684,502, can be used as a sensitizer. This eutectic complex is 1 e.g. 4-[4-bis(2-chloroethyl)aminophenyl]
-2,6-cyphenylthiapyrylium perchlorate and poly(4,4゛-isopropylidene diphenylene carbonate) in a halogenated hydrocarbon solvent such as dichloromethane, chloroform, carbon tetrachloride, 1゜1-dichloroethane, 1.2-dichloroethane.

1.1.2-) After dissolving in dichloroethane, chlorobenzene, bromobenzene, 1,2-dichlorobenzene, etc., add a non-polar solvent such as hexane, octane, decane, 2,2.4-1-limethylhenzene, ligroin to this. It can be obtained as a particulate eutectic complex by adding, etc.

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

Vinyl resin, vinylidene chloride-acrylonitrile copolymer, styrene-acrylonitrile copolymer (vinyl acetate) - vinyl chloride copolymer containing polyvinyl butyral, polymethyl methacrylate, poly-N-butyl methacrylate, polyesters, cellulose esters, etc. as a binder. Can be done.

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.

[Examples] Example 1 An ammonia aqueous solution of casein (11.2 g of casein, 1 g of 28% ammonia water, 222 mJL of water) was coated on an aluminum cylinder by a blade coating method to form a subbing layer with a dry film thickness of 1 pm.

Next, 10 g of a charge generating substance represented by the following structural formula, 5 g of butyral resin (degree of butyralization: 63 mol %), and 200 g of cyclohexanone were dispersed in a ball mill for 48 hours to prepare a coating solution.

This coating solution was applied onto the undercoat layer by a blade coating method to form a charge generation layer with a dry film thickness of 0.15 μm.

Next, add 10 g of compound example (8) and the log of polymethyl methacrylate (average molecular weight 50,000) to 70 g of chlorobenzene.
This solution was applied onto the previous charge generation layer by a blade coating method to form a charge transport layer having a dry thickness of 19 gm, thereby producing an electrophotographic photoreceptor.

The electrophotographic photoreceptor thus prepared was corona charged at -5 KV using an electrostatic copying paper tester FF1Model 3P-428 manufactured by Kawaguchi Electric Co., Ltd. using the static method, and after being held in a dark place for 1 second, it was charged at an illuminance of 20 KV. It was exposed to lux light and its charging characteristics were investigated.

As for the charging characteristics, the exposure amount (E 1/2) required to attenuate the potential (vl) to 1/2 when dark decaying for 1 second was measured.

Furthermore, in order to measure the fluctuations in bright area potential and dark area potential during repeated use, the electrophotographic photoreceptor prepared in the wood example was attached to the photosensitive drum cylinder of Canon Auxiliary PPC Copying Machine NP-3525. 5,000 copies were made with the same machine, and the bright area potential (initial and after 5,000 copies) was
ML) and dark potential (Vn) fluctuations were measured.

In addition, initial stage (7) Vo to VL each 'r -700V
, 200v.

Comparative Example 1 For comparison, a compound with the following structure (Japanese Unexamined Patent Publication No. 55-16
No. 1247), an electrophotographic photoreceptor was prepared in the same manner as above, and the electrophotographic properties were measured in the same manner.

Show the results.

Example 1 Comparative Example 1 -705 1.4 -670 4.8 Period V) From 5,000 sheets, after (V) Example I Vo -700-685VL -2
00-205 Comparative Example I VD -700-625VL -
200-260 As is clear from the above results, when the charge transport material specified in the present invention is used, it has good sensitivity and the potential fluctuation over time is extremely small.

Examples 2 to 15 In each of these Examples, the charge transport compound example (8) used in Example 1 was replaced with compound example (1).

(3), (4), (5), (7), (9), (11),
(14), (16), (17), (21), (23),
An electrophotographic photoreceptor was prepared using (24) and (27) and a pigment having the following structural formula as a charge generating substance, but in the same manner as in Example 1 except for the following conditions.

The electrophotographic characteristics of each photoreceptor were measured using the same method as in Example 1 to determine δ! I added four. Show the results.

(l 4) (l 6) (l 7) Initial Example D 700 2.1 700 2.8 705 3.9 675 1.5 650 4.0 675 2.9 690 2.6 695 1.0 690 1.8 700 3.4 675 3.9 690 3.1 685 2.8 685 2.1 L V after 5,000-sheet durability Example 16 Exemplary compound (8) used in Example 1 was used instead of compound example (8).
An electrophotographic photoreceptor was prepared in the same manner as in Example 1 except that Example 14) was used.

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), and the surface potential after the photoreceptor was left in a dark place for 1 second was measured.

Sensitivity is the exposure amount (El/2, microjoule/C'i) required to attenuate the potential vl after dark decay to 1/2.
m 2 ) was evaluated.

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

V, Knee 710V Vl Knee 705VEl/2
: 1.7 microjoules/cm 2. Next, the photoreceptor was transferred to a laser beam printer (LBP-CX, manufactured by Canon Mari), 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 photoreceptor.

The conditions were: surface potential knee 700 V after negative charging, surface potential knee 150 V after image exposure (exposure amount 2.0 microjoules/cm2), transfer potential: +700 V, developer polarity: negative polarity, process speed: 50 mm. /sec, development conditions (development bias) knee 450V, image exposure scan method:
Image scan, - exposure before next charging: 50x ux, se
The formation of one red full exposure image in c was carried out by line scanning a laser beam in accordance with the character signal and image signal, and good prints were obtained for both the character image and the image. Furthermore, 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-cyphenylthiapyrylium perchlorate and compound example (4
) and 5g of polyester (Polyester Adhesive 4
9000, manufactured by DuPont) toluene (50 parts by weight) -
The mixture was mixed with 100 ml of dioxane (50 parts by weight) 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 drying 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 705V Vl knee 695Vel/2
: 1.9L; Lux, sec handling -1 VD Knee 700V VL Knee 200V11 Kusara Katsuyuki Vo Knee 680V VL Knee 215V Example 1
8 3 g of 4-(4-dimethylaminophenyl)-2,6-diphenylthiapyrylium verchlorate and poly(4,
4°-isopropylidene diphenylene carbonate) 3
After sufficiently dissolving g in 200 ml of dichloromethane, toluene loO+nJl was added to precipitate the eutectic complex.

After filtering this precipitate, dichloromethane was added to redissolve it, and then 100 mJl 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 m of a methanol solution containing 2 g of polyvinyl butyral, and dispersed using a ball mill disperser for 6 hours. This dispersion was applied onto an aluminum slope having a casein layer using a Mayer bar so that the film thickness after drying was 0.4 m to form a charge generation layer.

Next, a covering layer of a charge transport layer was formed in the same manner as in Example 1 except that Compound Example (8) 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 695V Vl knee 690Vel/
2: 1.2Jlux-se.

First-1st period VD Knee 700V VL Knee 200V Dan's medical examination (I VD Knee 695V VL Knee 200V Example 1
9 An ammonia aqueous solution of casein (described above) was applied on an aluminum plate using a Meyer bar to form a subbing layer with a dry film thickness of 14 m. On top of this, the charge transport layer and charge generation layer of Example 1 were sequentially laminated, and an electrophotographic photoreceptor was prepared in the same manner as in Example 1 except for the layer structure, and the charging properties were the same as in Example 1. was measured. However, the charging polarity was set to 10. Show the results.

V6: +710V VL: +700VEl/
2: l, 9jlux-sec Example 20 5 g of a disazo pigment having the following structural formula was dispersed in a sand mill for 24 hours with a solution of 2 g of butyral resin (butyralization degree 63 mol%) dissolved in 100 mJl of cyclohexanone to prepare a coating solution. did.

This coating solution was applied onto an aluminum sheet using a Mayer bar to a dry film thickness of 0.2 μm to form a charge generation layer.

Next, 10 g of Compound Example (8) and 10 g of polycarbonate (average molecular weight 20,000) as a charge transport substance were dissolved in 70 g of chlorobenzene, and this solution was applied onto the charge generation layer using a Mayer bar to obtain a dry film thickness. A charge transport layer of 20 pm was formed.

The electrophotographic photoreceptor thus produced was evaluated in the same manner as in Example 1.

Vo Knee 710V Vl Knee 705VEl
/2: 2.31ux-sec Payment - 1st period Vo Knee 700V VL Knee 200V
Dan” L size - [Ki Vo Knee 680V VL Knee 215V
[Effects of the Invention] The electrophotographic photoreceptor containing the specific pullpene compound of the present invention has high sensitivity and has extremely low fluctuations in bright area potential and dark area potential during continuous image formation by repeated charging exposure, so it has excellent durability. It is an electrophotographic photoreceptor with excellent properties.

Claims (1)

[Scope of Claims] 1. An electrophotographic photoreceptor comprising a photosensitive layer laminated on a conductive support, wherein the photosensitive layer contains a fulvene compound represented by the following general formula. General formula ▲There are mathematical formulas, chemical formulas, tables, etc.▼ In the formula, R_1 and R_2 are the same or different and represent an alkyl group, an aralkyl group, or an aromatic ring group, and R_3 represents a hydrogen atom, an alkyl group, an alkoxy group, or a halogen atom. , R_4 represents a hydrogen atom, an alkyl group, an aralkyl group, or an aromatic ring group, R_5, R_6, R_7
and R_8 are the same or different and represent a hydrogen atom, an alkyl group, or an aromatic ring group, R_1, R_2 and R_
The alkyl group or aromatic ring group of 4 may have a substituent.