JPH01219844A - Electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To enhance reproduction performance of a copied image and sensitivity by incorporating a polycyclic compound and a specified compound in an electric charge generating layer. CONSTITUTION:The charge generating layer contains the polycyclic compound and one of the compounds represented by formula I in which A is formula II or the like; each of R1 and R2 is H or the like; R3 is alkyl or the like; (n) is 1, 2, or 3; thus permitting the obtained photosensitive body to be high in sensitivity, adapted in spectral sensitivity to electrophotographic copying machines, printers, and the like, especially, excellent in copying reproducibility of a red image, and stabilized in characteristics also at the time of repeated uses.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to an electrophotographic photoreceptor using two types of charge generating substances.

[Background of the Invention] Electrophotographic photoreceptors are generally widely used in electrophotographic copying machines, printers, and the like, but the characteristics required of the electrophotographic photoreceptors differ depending on the use. For example, in electronic photocopying, especially in office copying machines, the reproduction image reproducibility of red images (for example, red stamp characters, underlines, etc.) is important as well as the reproduction image reproduction of black and blue originals. be done. In order to achieve these types of copy image reproducibility, it is desired that the electrophotographic photoreceptor has sufficient spectral sensitivity in the range of 450 nm to 600 nm (620 nm at most). The spectral sensitivity of the electrophotographic photoreceptor is 6
If the wavelength extends to around 60 nm or 700 nm, the reproduction reproducibility of the above-mentioned red image will be poor, making it undesirable for use as an office copy. For this reason, electrophotographic photoreceptors using ordinary azo pigments, especially disazo pigments and trisazo pigments as charge-generating substances (for example, JP-A-47-3754, JP-A-53-1
No. 33445, No. 58-70232, No. 5g-140
No. 745, etc.), the spectral sensitivity extends to around 700 nm, so they are used by cutting off light with wavelengths of 620 to 630 nm or more with a filter to reduce red sensitivity.

However, when such a filter is used, not only the red sensitivity but also the short wavelength sensitivity decreases, resulting in a disadvantage that the overall sensitivity decreases. Furthermore, when such an azo pigment is used as a charge generating substance, it is necessary to form the charge generating layer with an a film having a thickness of about 0.1 to 0.3 μm due to its low charge transport ability. When such a N film is applied by a dip coating method, which is a common manufacturing method, coating defects such as step unevenness, liquid dripping, and aggregation are likely to occur, leading to a decrease in yield and an increase in cost.

Furthermore, polycyclic quinone pigments are known as pigments with good copy image reproducibility (see JP-A-57-67933). Polycyclic quinone pigments have high sensitivity in the 4sonm to 570nm region, and therefore have excellent copying reproducibility of red images, and are also superior in terms of sensitivity, charging potential, residual potential, etc. compared to azo compounds and phthalocyanine compounds. It is characterized by extremely stable repetition characteristics. However, when this polycyclic quinone pigment is used, 57
Sensitivity decreases significantly in the region of 0r+m or higher, 580-62
Since it has almost no sensitivity in the region around 0 nm,
The sensitivity is insufficient for use in high-speed copying and small-sized copying machines that require high sensitivity.

Furthermore, Japanese Patent Application Laid-open No. 61-292158 discloses a technique that uses a combination of two types of charge-generating materials with different photomemories. Although this technique has high sensitivity, it has the drawbacks of charge-generating materials with large photomemories. The purpose of this method is to improve the reproduction of red images as described above, and no study has been made on the reproduction reproducibility of red images.

As described above, the actual situation is that techniques that can achieve the above-mentioned copy image reproducibility and high sensitivity have not been sufficiently studied.

[Object of the invention] The present invention has been made in view of the above-mentioned conventional problems,
First, to provide a highly sensitive electrophotographic photoreceptor that has spectral sensitivity characteristics suitable for electrophotographic copying machines, printers, etc., and second, to provide a highly sensitive electrophotographic photoreceptor with excellent copying reproducibility of red uniformity. We provide photographic photoreceptors.

Thirdly, it is an object of the present invention to provide an electrophotographic photoreceptor with excellent repeatability.

[Structure of the Invention] The above object of the present invention is to provide an electrophotographic photoreceptor having at least a charge generation layer and a charge transport layer on a conductive support, wherein the charge generation layer contains a polycyclic quinone compound and the following general formula [I The general formula [I] is represented by an electrophotographic photoreceptor characterized by containing a compound represented by the formula [I]. R1 and R2 each represent a hydrogen atom, a halogen atom, an argyl group, an alkoxy group or an i:t hydroxyl group, R3 represents an alkyl group or an alkoxycarbonyl group, and u+1 represents 1.2 or 3.

In the general formula [I], the halogen atom represented by R1 or R2 includes, for example, a chlorine atom, a bromine atom, etc., the argyl group includes, for example, a methyl group, an ethyl group, and the alkoxy group includes, for example, a methoxy group. , hydroxyl group, etc. Further, examples of the alkyl group represented by R3 include a methyl group and an ethyl group, and examples of the alkoxycarbonyl group include a me-1-oxycarbonyl group and an ethoxycarbonyl group.

Representative specific examples of the compound represented by the general formula [11] (hereinafter referred to as the azo compound of the present invention) are shown below, but the invention is not limited thereto.

The above azo compounds are disclosed in Japanese Patent Application Laid-open No. 47-37543, for example.
It can be easily synthesized by the method described in No.

The polycyclic quinone compounds used in the present invention include an anthoan-1-rone pigment represented by the following general formula [A], a dibenzpyrenequinone pigment represented by the following general formula [8], and the following general formula [C] At least one type selected from the pyranthrone pigments represented by the following can be mentioned, and the general formula [△] is particularly preferred.

General formula [A] General formula [B] General formula [C1 In the formula, X represents a halogen atom, a nitro group, a cyano group, an acyl group, or a carboxyl group, 0 represents an integer from 0 to 4; Represents an integer of 6.

Specific compounds of the anthorone pigment represented by the general formula [A] are as follows.

[Al1 [A2] [A3
] [A4] [A5]
[A6] [A? ]
[A8] [A9] [A10] [A11] Specific compound examples of the dibenzpyrenequinone pigment represented by the general formula [B] are as follows.

[B11 [B11 [B11 [B4] [B11 [B11 [B7]] [B11 [B11] Specific compound examples of the pyranthrone pigment represented by the general formula [C] are as follows.

[C11 [C2] [C3] [C4] [C5] [C6] [C7] [C8] [C9] The above polycyclic quinone compounds can be synthesized by known methods, but they are not available as commercial products. You can also.

Various configurations of electrophotographic photoreceptors are known, but
The electrophotographic photoreceptor of the present invention can take any of these forms.

Usually, the configuration is as shown in FIGS. 1 to 6. Figures 1 and 2
In the figure, a charge generation layer 2 containing the above-mentioned polycyclic quinone compound and the azo compound of the present invention is formed on a conductive support 1, and a charge transport layer 3 containing a charge transport substance described below as a main component is formed on a conductive support 1. A photosensitive layer 4 consisting of a layered body is installed, and the first
The stacking order of the charge generation layer 2 and the charge transport layer 3 is different between the figure and FIG.

As shown in FIGS. 3 and 4, this photosensitive layer 4 may be provided on a conductive support with an intermediate layer 5 such as an adhesive layer or a barrier layer interposed therebetween. In this way, when the photosensitive layer 4 has a nitro structure, a photoreceptor having the most excellent electrophotographic properties can be obtained. Further, in the present invention, as shown in FIGS. 5 and 6, the photosensitive layer 4, which is formed by dispersing the polycyclic quinone compound and the azo compound of the present invention in a layer 6 containing a charge transport substance, is made of a conductive material. It may be provided directly on the support 1 or via an intermediate layer 5. Further, in the present invention, a protective layer may be provided as the outermost layer.

The charge generation layer 2 constituting the photosensitive layer 4 having a two-layer structure is formed directly on the conductive support 1 or the charge transport layer 3, or on an intermediate layer 5 such as an adhesive layer or a barrier layer as required. For example, it can be formed by the following method.

~1-1) Apply a solution in which the polycyclic quinone compound and the azo compound of the present invention are dissolved together or separately in a suitable solvent, or a solution in which a binder resin is added and mixed as necessary. Method.

M-2) The polycyclic quinone compound and the azo compound of the present invention are made into fine particles (preferably particle size of 5 μm or less, more preferably 1 μm or less) in a dispersion medium using a ball mill, homomixer, etc., and as necessary. A method in which a binder resin is added and a mixed and dispersed dispersion is applied.

Examples of the solvent or dispersion medium used for forming the charge generation layer include n-butylamine, diethylamine, ethylenediamine, isopropanolamine, triethanolamine, 1-lyethylenediamine, N,N-dimethylformamide, acetone, methylethylketone, and cyclohexanone. , benzene, toluene, xylene, chloroform,
1,2-dichloroethane, 1,2-dichloropropane,
1゜1.2-1~lichloroethane, 1.1.1-trichloroethane, 1~lichloroethylene, te1~lachloroethane, dichloromethane, te1~lahydrofuran, dioxane, methanol, ethanol, impropatol, ethyl acetate , butyl acetate, dimethyl sulfoxide, methyl cellosolve, and the like.

Further, the charge transport layer can be formed in the same manner as the charge generation layer described above.

Any binder resin can be used to form the charge generation layer or the charge transport layer, but it is preferable to use a film-forming polymer that is hydrophobic, has a high dielectric constant, and is electrically insulating. preferable. Examples of such high molecular weight polymers include, but are not limited to, the following.

P-1) Polycarbonate P-2) Polyester P-3) Methacrylic acid P-4) Acrylic resin P-5) Polyvinyl chloride P-6) Polyvinylidene chloride P-7> Polystyrene P-8) Polyvinyl acetate P-9 ) Styrene-butadiene copolymer P-10) Vinylidene chloride-acrylonitrile copolymer P-11) Vinyl chloride-vinyl acetate copolymer P-12)
Vinyl chloride-vinyl acetate-maleic anhydride copolymer P-13) Silicone resin P-14) Silicone-alkyd resin p-15) Phenol formaldehyde resin p-16) Styrene-
Flukyd resin p-17) Poly-N-vinylcarbazole p-18) Polyvinyl butyral p-19) Polyvinyl formal These binder resins can be used alone or as a mixture of two or more.

In the charge generation layer formed as described above, the ratio of the charge generation substance comprising the polycyclic quinone compound and the azo compound of the present invention to the binder is preferably 100:O.
~1000. If the content of the charge generating substance is less than this, the photosensitivity will be low and the residual potential will increase, and if it is more than this, the dark decay and acceptance potential will decrease.

Further, the combined ratio of the polycyclic quinone compound and the azo compound of the present invention is preferably +00:1 to 100:30 in terms of weight ratio.If the ratio of the azo compound is higher than this, the reproduction reproducibility of red images will be decreases.

Further, the average particle size of the particles of the polycyclic quinone compound used in the present invention is preferably larger than the average particle size of the particles of the azo compound of the present invention.

The thickness of the charge generation layer to be formed is preferably 0.01 to 0.01.
It is 10μI.

Further, in the charge transport layer formed as described above, the charge transport material is the binder resin 100 in the charge transport layer.
It is preferably 20 to 200 parts by weight per part of ffl a, particularly preferably 30 to 150 parts by weight.

Further, the thickness of the charge transport layer to be formed is preferably 5 to 5.
50 μm, particularly preferably 5 to 30 μm.

The charge transporting substance used in the present invention is not particularly limited, but includes, for example, oxazole derivatives, oxadiazole derivatives, thiazole derivatives, thiadiazole derivatives, triazole derivatives, imidazole derivatives, imidacilone derivatives, imidazolidine derivatives, bisimidazolidine. Derivatives, styryl compounds, hydrazone compounds, pyrazoline derivatives, amine derivatives, oxacilone conductors, benzothiazole derivatives, benzimidazole derivatives, quinazoline conductors, benzofuran N8, acridine derivatives, phenazine derivatives (wood, aminospurben derivatives,
These include poly-N-vinylcarbazole, poly-1-vinylpyrene, poly-9-quinylanthracene, and the like.

The charge transport layer used in the present invention has an excellent ability to transport holes generated during light irradiation to the support side, and is also suitable for combination with the polycyclic quinone compound and the azo compound of the present invention. is preferably used, and preferable charge transport materials are those represented by the following general formula (A), (
Examples include those represented by B) and (C).

General formula (A) However, Art, Ar2, and Ar-1 each represent a substituted or unsubstituted aryl group, ArJ represents a substituted or unsubstituted arylene group, and R1 is a hydrogen atom or a substituted or unsubstituted alkyl group. , or a substituted or unsubstituted aryl group.

Specific examples of such compounds are given in JP-A-58-654, 10.
Pages 3-4 of @ and No. 3-G of No. 58-198043
It is described in detail on the page.

General formula (B) However, R1 is a substituted or unsubstituted aryl group, or a substituted.

It is an unsubstituted hetero 11 group, and R2 is a hydrogen atom and is substituted.

Represents an unsubstituted alkyl group, a substituted or unsubstituted aryl group, and is described in detail in JP-A No. 58-134 [342 and 58].
It is not described in the publication of No.-166354.

General formula (C) R3 However, R1 is a substituted, unsubstituted aryl group, and R2 is a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group,
Substituted, unsubstituted alkoxy group, substituted.

unsubstituted amino group, hydroxy group, R3 is substituted,
Represents an unsubstituted aryl group, substituted or unsubstituted heterocyclic group. Synthesis methods and examples of these compounds are given in Japanese Patent Publication No. 57-
It is described in detail in Japanese Patent No. 148750, and can be incorporated into the present invention.

Other preferred charge transport materials of the present invention include JP-A-57-67940, JP-A-59-15252, and JP-A-57.
Examples include hydrazone compounds described in JP-101844.

The conductive support used in the electrophotographic photoreceptor of the present invention is a metal plate including an alloy, a metal drum or a conductive polymer, a conductive compound such as indium oxide, aluminum including an alloy, palladium, gold, etc. Apply a thin layer of metal,
Examples include paper and plastic films made conductive by vapor deposition or lamination. As an intermediate layer such as an adhesive layer or a barrier layer, in addition to the polymer used as the binder resin, an organic polymer material such as polyvinyl alcohol, ethyl cellulose, carboxymethyl cellulose, or aluminum oxide is used.

Organic amines may be added to the photosensitive layer of the present invention for the purpose of improving the charge generating function of the charge generating substance, and in particular, organic amines may be added to the photosensitive layer.
Preferably, a grade amine is added.

Such secondary amines include, for example, dimethylamine, diethylamine, di-n propylamine, di-isopropylamine, di-n butylamine, di-isobutylamine, di-n amylamine, di-isoamylamine, di-n
Hexylamine, di-isohexylamine, di-n-pentylamine, di-isopentylamine, di-n-octylamine, di-isooctylamine, di-n-nonylamine, di-isononylamine, di-n-decylamine, di- Examples include isodecylamine, di-n-monodecylamine, di-isomonodecylamine, di-n-doazylamine, and di-isododecylamine.

The molar amount of the organic amine to be added is preferably 1 times or less, preferably 0.2 times to 0,00 times the amount of the charge generating substance.

Further, an antioxidant can be added to the photosensitive layer of the present invention for the purpose of preventing ozone deterioration.

Typical examples of such antioxidants are shown below, but the invention is not limited thereto.

Group (I): Hindered phenols dibutylhydroxytoluene, 2,2'-methylenebis(6-t-butyl-4-methylphenol), 4.4'
-butylidenebis(6-t-butyl-3-methylphenol>, 4.4'-thiobis(6-t-butyl-3-
methylphenol), 2,2'-butylidene bis(6-
t-butyl-4-methylphenol), α-tocopherol, β-tocopherol, 2.2.4-trimethyl-
6-hydroxy 7-t-butylchroman, pentaerythyltetrakis [3-(3,5-diC-butyl-4
-hydroxyphenyl)propionate], 2.2'
-thiodiethylenebis[3-(3°5-di-t-butyl-4-hydroxyphenyl)propionate], 1.6
-hexanediol bis[3-<3.5-di-butyl-4-hydroxyphenyl)propionate], butylhydroxyanisole, dibutylhydroxyanisole, 1-[2-((3,5-di-tert-butyl-4)
-hydroxyphenyl)propionyloxy)ethyl]
-'4- [3-(3,5-di-tert-butyl-4-hydroxyph1nyl)propionyloxy]-2,
2,6,6-tetramethylpiveridyl, etc.

Group (II): paraphenylenediamines N-phenyl-
N'-isopropyl-p-phenylenediamine, N,N
'-5ec-butyl-p-phenylenediamine, N
-Phenyl-N-3eC-butyl-p-phenylenediamine, N.

N'-diinpropyl-p-phenylenediamine, N,
N'-dimethyl-N, N'-di[-butyl-p-phenylenediamine, etc.

(I[l) group: Hydroquinones 2.5-di(-octylhydroquinone, 2゜6-sidodecylhydroquinone, 2-dodecylhydroquinone, 2-dodecyl-5-chlorohydroquinone, 2-t-
Octyl-5-methylhydroquinone, 2-(2-octadecenyl)-5-methylhydroquinone, etc.

(rV) group: organic sulfur compounds dilauryl-3,3'-thiodipropionate, distearyl-3,3'-thiodipropionate, ditetradecyl-3,3'-thiodipropionate, etc.

Group (V): phosphorous compounds such as triphenylphosphine, tri(nonylphenyl)phosphine, tri(dinonylphenyl)phosphine, tricresylphosphine, tri(2,4-dibutylphenoxy)phosphine.

These compounds are known as antioxidants for rubber, plastics, oils and fats, and are easily available commercially.

These antioxidants may be added to any of the charge generation layer, charge transport layer, or protective layer, but are preferably added to the charge transport layer. In that case, the amount of the antioxidant added is 01 to 100 parts per 100 parts of the charge transport material.
Preferably it is 1 to 50 parts by weight, particularly preferably 1 to 25 parts by weight.

In the present invention, the charge generation layer may contain one or more electron-accepting substances for the purpose of improving sensitivity, reducing residual potential, and reducing fatigue during repeated use.

Examples of electron-accepting substances that can be used here include succinic anhydride, maleic anhydride, dibromaleic anhydride, phthalic anhydride, tetrachlorophthalic anhydride,
Tetrabromo phthalic anhydride, 3-nitro phthalic anhydride,
4-nitrophthalic anhydride, pyromellitic anhydride, mellitic anhydride, 1-lacyanoethylene, 1-lacyanoquinodimethane, 0-dinitrobenzene, 1-dinitrobenzene, 1.3.5-trinitrobenzene, Varanitrobenzonitrile, vicryl chloride, quinone chlorimide, chloranil, brumanil, dichlorodicyanobarabenzoquinone, anthraquinone, dinitroanthraquinone, 2.7-sinitrofluorenone, 2.4.7-trinitrofluorenone, 2°4.5 .7-Tetranitrofluorenone, 9-fluorenylidene [dicyanomethylenemalonodinitrile], polynitro-9-fluorenylidene-[dicyanomethylenemalonodinitrile], picric acid, 0-nitrobenzoic acid, p-nitrobenzoic acid, 3.5 −
Examples include dinitrobenzoic acid, pentafluorobenzoic acid, 5-nitrosalicylic acid, 3,5-dinitrosalicylic acid, phthalic acid, mellitic acid, and other compounds with high electron affinity.

The amount of the electron-accepting substance added is such that the weight ratio of charge-generating substance to electron-accepting substance is 100:0.01-200, preferably 100:0.1-100.

An electron-accepting substance may be added to the charge transport layer.

The amount of the electron-accepting substance added to this layer is such that the weight ratio of charge-transporting substance:electron-accepting substance is 100:0.01~
100, preferably 100:0.1-50.

In addition, the photoreceptor of the present invention may also contain, if necessary, an ultraviolet absorber or the like for the purpose of protecting the photosensitive layer, and may also contain a dye for color sensitivity correction.

The electrophotographic photoreceptor of the present invention has the above-mentioned structure,
As is clear from the examples described below, it has high sensitivity and spectral sensitivity characteristics suitable for electrophotographic photoreceptors, printers, etc., has excellent copying reproducibility, especially for red images, and is even more durable after repeated use. It also has stable characteristics.

Further, the electrophotographic photoreceptor of the present invention has good characteristics as a photoreceptor even when a relatively thick charge generation layer is formed, and therefore, there are fewer coating defects during manufacturing as described above, which is advantageous in terms of production. be.

[Examples] Hereinafter, the present invention will be specifically explained using Examples, but the embodiments of the present invention are not limited thereby.

Example-1 5 g of polycarbonate resin (Panlite L -1250° Yojin Kasei (manufactured by Toko) was mixed with 20 Q of 1,2-dichloroethane.
After dissolving in IQ, 310 g of an exemplified polycyclic quinone compound [A3] as a charge generating substance CGM2 was mixed and dispersed with a sand grinder for 10 hours. This is called liquid A.

Next, after dissolving 1 g of the above polycarbonate resin in 1,2-dichloroethane 1201R, the charge generating substance CGMI
8.2g of Exemplified Azo Compound No. was mixed with the mixture, and the mixture was ground with a sand grinder for 10. Spread out time.

This is called liquid B.

The above A liquid 200.12 and B liquid 201Q are stirred and mixed to form a coating liquid for forming a charge generation layer, and this is applied onto a polyester base subjected to AP thermal evaporation using a wire bar, and after drying, the film thickness is approximately 0.3 μm. A charge generation layer is formed.

Next, a charge transport layer having a thickness of about 20 μm after drying was laminated on the charge generation layer using a blade using a coating liquid for forming a charge transport layer having the composition shown below to obtain a photoreceptor.

1.2-dichloroethane 10 (15 g of ld polycarbonate resin (same as above)) The obtained photoreceptor is designated as sample No. 61.

Next, in sample No. 0.1, except for changing the charge generating substance used or the combination ratio thereof as shown in Table 1
Samples No. 2 to 8 were prepared in the same manner as No. 1.

Characteristic evaluation tests of photoreceptor samples Nos. 011 to 8 thus obtained were conducted as follows.

[Sensitivity test] Electrostatic charging test device EPA-8100 (Kawaguchi Type 1 Co., Ltd.)
The exposure filE1/2 (, 1 uX-3eC) required for the photoreceptor surface potential to be halved from the initial potential was measured using the following.

[Repetitive characteristic test 1 Using the above electrostatic charging test device EPA-8100, charging → exposure → static elimination was repeated 100 times.
The change in band N potential at the 0th time was measured at 18 VO-6100 (v).

[Red color reproducibility test] Using a modified electrophotographic copying machine R U-Bix 1550 J (manufactured by Konica TTIL) and equipped with a surface electrometer, a Kodak Power Control Patch was used as a manuscript, and the black paper therein was used. The potential is -600V, and the blank potential is -100V.
The surface potential Vred (V) of the photoreceptor corresponding to the red batch was measured when copying was performed in accordance with (2).

The lower the value of V red, the worse the reproducibility of the red image.

From the results of this comparative 7zo compound Table-1, the photoreceptor of the present invention exhibits superior performance in all respects, such as sensitivity, red image copying reproducibility, and repeatability, compared to the comparative photoreceptor. is clear.

Example 2 The combination of the charge generating substances used was changed as shown in Table 2, and the polycarbonate 1 to resin used in the coating liquid for forming the charge transport layer was changed to: L-P[1-Z- Samples Nos. 9 to 14 were prepared in the same manner as in Example-1 except that 200 (manufactured by Mitsubishi Gas Chemical (IM)) was used, and the same characteristic evaluation tests as in Example-1 were conducted on these samples. The results are not shown in Table 2.

From the results in Table 2, it can be seen that the photoreceptor of the present invention exhibits superior performance in all aspects of sensitivity, red image copying reproducibility, and repeatability.

Example-3 The combination of charge-generating substances used was changed as shown in Table-3, and the amount of polycarbonate used in the coating solution for forming the charge transport layer was changed to 1-2 (the fat was replaced with Kneepilon 2-200 (mentioned above)). Samples Nos. 15 to 18 were prepared in the same manner as in Example-1 except that the charge transport substance was replaced with , and the same 1! characteristics evaluation 1i1!i test as in Example-1 was conducted on these samples. The results obtained are shown in Table 3. From the results in Table 3 below, it is clear that the photoreceptor of the present invention exhibits excellent performance in all aspects of sensitivity, copying reproducibility of red images, and repeatability. I understand.

Example-4 The combination U of charge-generating substances used was changed as shown in Table-4, and the polycarbonate 1 to resin used in the coating liquid for forming the charge transport layer was replaced with Nipiron 2-200 (mentioned above). , Sample No. 1 was prepared in the same manner as in Example-1 except that the charge transport substance was replaced with .

Examples 19 to 22 were prepared, and Example 1
Table 4 shows the results obtained by conducting a characteristic evaluation test similar to
Shown below.

Remaining 1℃・T:] r, · ° Sakae ・−3・,′.

From the results in Table 4, it can be seen that the photoreceptor of the present invention exhibits excellent performance in all respects of sensitivity, copying reproducibility of red images, and repeatability.

[Brief explanation of the drawing]

FIGS. 1 to 6 are cross-sectional views showing structural examples of the photoreceptor of the present invention, respectively. 1... Conductive support 2... Charge generation layer 3... Charge transport layer 4... Photosensitive layer 5... Intermediate layer 6... Characterized by charge transport material

Claims (1)

[Claims] An electrophotographic photoreceptor having at least a charge generation layer and a charge transport layer on a conductive support, wherein the charge generation layer contains a polycyclic quinone compound and a compound represented by the following general formula [I]. An electrophotographic photoreceptor comprising: General formula [I] ▲There are mathematical formulas, chemical formulas, tables, etc.▼ [In the formula, A is ▲There are mathematical formulas, chemical formulas, tables, etc.▼, ▲There are mathematical formulas, chemical formulas, tables, etc.▼ or ▲Mathematical formulas, chemical formulas, tables, etc. There is ▼. R_1 and R_2 each represent a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, or a hydroxyl group. R_3 represents an alkyl group or an alkoxycarbonyl group. n represents 1, 2 or 3. ]