JPH0213962A - Electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To enhance sensitivity and durability by forming a photosensitive layer containing a specified triarylamine derivative on a conductive substrate. CONSTITUTION:The photosensitive layer 4 formed on the conductive substrate 1 is a laminate comprising a carrier generating layer 2 composed essentially of a carrier generating material and a carrier transfer layer 3 composed essentially of the carrier transfer material represented by formula I in which each of Ar1 and Ar2 is optionally substituted or unsubstituted aryl; Ar3 is optionally substituted or unsubstituted arylene; each of R1-R8 is H, halogen, optionally substituted or unsubstituted alkyl, such alkoxy, or the like; and X is O, S, or the like, thus permitting the obtained photosensitive body to obtain high sensitivity and high durability.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to an electrophotographic photoreceptor, and more particularly to an electrophotographic photoreceptor having a photosensitive layer containing an organic photoconductive compound as a main component.

[Prior art]

Conventionally, inorganic photoreceptors having a photosensitive layer containing an inorganic photoconductive compound such as selenium, zinc oxide, cadmium sulfide, or silicon as a main component have been widely used as electrophotographic photoreceptors. However, these were not necessarily satisfactory in terms of sensitivity, thermal stability, moisture resistance, durability, etc. For example, when selenium crystallizes, its properties as an electrophotographic photoreceptor deteriorate, making it difficult to manufacture.Also, selenium crystallizes due to heat, fingerprints, etc., and its performance as an electrophotographic photoreceptor deteriorates. In addition, cadmium sulfide and zinc oxide
There were problems with moisture resistance and durability.

In order to overcome these drawbacks of inorganic photoreceptors, research and development have been actively conducted in recent years on organic photoreceptors having photosensitive layers containing various organic photoconductive compounds as main components.

For example, Japanese Patent Publication No. 50-10496 describes an organic photoreceptor comprising a photosensitive layer containing poly-N-vinylcarbazoleolenon. However, this photoreceptor is not necessarily satisfactory in terms of sensitivity and durability.

In order to improve these drawbacks, attempts have been made to develop a high-performance organic photoreceptor in which the carrier generation function and the carrier transport function are shared by different substances. Many studies have been conducted on such so-called functionally separated photoreceptors because each material can be selected from a wide range and a photoreceptor having arbitrary performance can be produced relatively easily.

As a result, various azo compounds have been developed and put into practical use as carrier-generating substances. On the other hand, regarding carrier transport substances, for example, JP-A-51-94829, JP-A-52-72231, JP-A-53-27033, JP-A-55-
No. 52063, No. 58-65440, No. 58-198
A wide variety of substances have been proposed, as disclosed in No. 425 and the like.

[Problem that the invention seeks to solve]

Some electrophotographic photoreceptors using carrier transport materials such as those described above exhibit relatively excellent electrophotographic performance, but their durability against light, ozone, or electrical loads is weak, and performance may deteriorate after repeated use. Since it is stable and causes deterioration, it does not fully satisfy practical requirements, and it is desired to develop a carrier transport material that has even better carrier transport function and exhibits stable performance for long-term use. was.

Furthermore, the demand for installing organic photoreceptors in electrophotographic copying machines capable of copying at higher speeds has been increasing in recent years, and the development of photoreceptors with higher sensitivity and higher durability has been desired.

The present invention has been made to solve these problems and provide a highly sensitive and highly durable photoreceptor.

[Means for solving problems]

The above problem is solved by an electrophotographic photoreceptor having a photosensitive layer comprising a layer containing a triarylamine derivative represented by the following general formula [■] on a conductive support.

General formula (1) However, in the formula, Ar. , Ar2 represents a substituted or unsubstituted aryl group, preferably a substituted or unsubstituted phenyl group, or a substituted or unsubstituted naphthyl group. Ar, is substitution.

Represents an unsubstituted arylene group, preferably substituted.

Represents an unsubstituted phenylene group, substituted or unsubstituted naphthylene group. R,, R2, R3, R, R6, R7, R, may be the same or different, and each represents a hydrogen atom, a halogen atom, a substituted... It represents unsubstituted alkyl'2f, substituted or unsubstituted alkoxy group, substituted or unsubstituted aryl group, substituted or unsubstituted aryloxy group, or substituted amino group, and preferred aryl groups are phenyl group and naphthyl group. , a preferred aryloxy group is a phenoxy group.

X represents an oxygen atom, a sulfur atom, )NR, and R.

does not represent a hydrogen atom or a substituted or unsubstituted alkyl group.

That is, in the present invention, the carrier transporting ability of the compound represented by the general formula [1] is utilized to create a carrier transporting material for a functionally separated electrophotographic photoreceptor in which carrier generation and transport are performed using separate substances. By using it as a coating material, the film has excellent physical properties and electrophotographic properties such as charge retention, sensitivity, and residual potential.It also shows little fatigue deterioration even after repeated use, and is resistant to heat. It is possible to create an electrophotographic photoreceptor that exhibits stable characteristics even against ozone or light.

Further, the carrier transporting substance used in the present invention can be used alone or in combination of two or more of the compounds represented by the general formula [I], and can also be used in combination with other carrier transporting substances. Good too.

Specific examples of the carrier transport substance represented by the general formula [I] that are effective in the present invention include those having the following structural formula, but the carrier transport substance according to the present invention is limited by this. Exemplary Compounds The carrier transporting substances described above can be easily synthesized by known synthesis methods. For example, reference may be made to the method described in Japanese Publication No. 58-198425.

~ (Exemplary Compound (I)) 2.73 g (0.01 mole) of the above aldehyde (1) and 2.70 g (0.01 mole) of the above phosphonate (2) were added to 20 mQ of N,N-dimethylformamide, and sodium methane was added. 2.90 g of a 28% methanol solution of Lato was added dropwise at room temperature.

After the dropwise addition, the mixture was stirred in the chamber for 5 hours. After adding 6Qmf2 of water to the reaction solution and extracting with toluene, the toluene layer was washed with water and dried to remove toluene. Crystallize by adding a small amount of methanol, peel off the crystals, dry, and add n-hexano, toluene,
Recrystallization from a mixed solvent yielded 2.5 g (64
, 0%) A molecular ion peak of 389 was observed in the FD-mass spectrum, confirming that the target product was synthesized.

Next, as a carrier generating substance suitable for the present invention, an azo pigment is preferable, but in general, any inorganic pigment or organic pigment can be used as long as it absorbs visible light to infrared light and generates free carriers. be able to. For example, in addition to inorganic pigments such as amorphous selenium, trigonal selenium, selenium-arsenic alloy, selenium-tellurium alloy, and cadmium sulfide, organic pigments such as those shown in the following representative examples may be used.

(1) Azo pigments such as monoazo pigments, bisazo pigments, trisazo pigments, metal complex azo pigments, etc. (2) Perylene pigments such as perylene acid anhydride, perylene acid imide, etc. (3) Anthraquinone derivatives, anthanthrone derivatives, dibenzpyrene Polycyclic quinone pigments such as quinone derivatives, pyranthrone derivatives, violanthrone derivatives and isoviolanthrone derivatives (4) Indigoid pigments such as indigo derivatives and thioindigo derivatives (5) 7talo/anine such as metal phthalocyanine and metal-free phthalonanine Pigment-based carrier transport substances used in the present invention do not have the ability to form a film by themselves, so they are combined with various binders to form a photosensitive layer.

Although any binder can be used for the carrier generation layer and the carrier transport layer, it is preferable to use a hydrophobic electrically insulating film-forming polymer. Examples of such high molecular weight polymers include, but are not limited to, the following.

(1) Polycarbonate (2) Polyester (3) Methacrylic resin (4) Acrylic resin (5) Polyvinyl chloride (6) Polyhynylidene chloride (7) Polystyrene (8) Polyvinyl acetate (9) Styrene copolymer resin (e.g. styrene -butadiene copolymer, styrene-methyl methacrylate copolymer, etc.) (10) Acrylonitrile copolymer resin (for example, hnylidene chloride-acrylonitrile copolymer, etc.) (11) Vinyl chloride-vinyl acetate copolymer Polymer (12) Hynyl chloride-vinyl acetate-maleic anhydride copolymer (13) / silicone resin (1,1) silicone-alkyd resin (15) phenolic resin (16) styrene-alkyd resin (17) poly-
N-onylcarbazole (18) Polyhinyl butyral (19) Polyhinyl formal (20) Polyhydroxystyrene These binders can be used alone or in a mixture of two or more.

As shown in FIGS. 1 and 2, the photoreceptor of the present invention comprises a carrier generating layer 2 containing a carrier-generating substance as a main component on a conductive support l, and a carrier-generating layer 2 containing a carrier-generating substance as a main component and a compound of the present invention as a main component of a carrier-transporting substance. A photosensitive layer 4 made of a laminate with a carrier transport layer 3 containing the photosensitive layer 4 is provided.

As shown in FIGS. 3 and 4, this photosensitive layer M4 may be provided on the conductive support 1 via an intermediate layer 5.

When the photosensitive layer 4 has a two-layer structure in this manner, an electrophotographic photoreceptor having the best electrophotographic properties can be obtained. Further, in the present invention, as shown in FIGS. 5 and 6, a photosensitive layer 4 formed by dispersing a carrier generating substance 7 in the form of fine particles in a layer 6 mainly composed of the carrier transporting substance is used as a conductive support. (2) It may be provided directly on top or via an intermediate layer 5.

Furthermore, a protective layer 8 may be provided on the photosensitive layer 4 if necessary.

When the photosensitive layer 4 has a two-layer structure, which of the carrier generation layer 2 and the carrier transport layer 3 is to be the upper layer is determined by whether the charging polarity is positive or negative. That is, in the case of a negatively charged photosensitive layer, the carrier transport layer 3
It is advantageous to use the carrier transport layer 3 as the upper layer because the carrier transport material in the carrier transport layer 3 is a material that has a high transport ability for holes.

Further, a carrier generation layer 2 constituting a photosensitive layer 4 having a two-layer structure
can be formed directly on the conductive support l or the carrier transport layer 3 or after providing an intermediate layer such as an adhesive layer or a barrier layer if necessary, by the following method.

(1) Vacuum deposition method (2) Method of applying a solution of a carrier-generating substance dissolved in a suitable solvent (3) Forming the carrier-generating substance into fine particles in a dispersion medium using a ball mill, sand grinder, etc. as necessary.
A method of applying a dispersion obtained by mixing and dispersing a binder.

The thickness of the carrier generation layer 2 formed in this way is
0. It is preferably from 1 to 5 μm, more preferably from 0.05 to 3 μm.

Further, the thickness of the carrier transport layer 3 can be changed as necessary, but it is usually preferably 5 to 30 μm.

The composition ratio in this carrier transport layer 3 is preferably 0.8 to IO parts by weight of the binder to 1 part by weight of the carrier transport material of the present invention. When forming layer 4, it is preferable to use the binder in an amount of 5 parts by weight or less per 1 part by weight of the carrier-generating substance.

Further, when the carrier generation layer is configured as a dispersed layer using a binder, it is preferable to use the binder in an amount of 5 parts by weight or less per 1 part by weight of the carrier generating substance.

The layer structure of the photoreceptor of the present invention includes a laminated structure and a single layer structure as described above, and either a carrier transport layer serving as a surface layer, a carrier generation layer, a single layer photosensitive layer, or a protective layer, or a plurality of layers. The layer may contain one or more electron-accepting substances for the purpose of improving sensitivity, reducing residual potential, and reducing fatigue during repeated use.

Further, the intermediate layer functions as an adhesive layer or a barrier layer, and in addition to the binder resin, for example, haorivinyl alcohol, ethyl cellulose, carboxymethyl cellulose, casein, etc. are used.

As the conductive support l used in the construction of the electrophotographic photoreceptor of the present invention, the following are mainly used, but the invention is not limited thereto.

(1) Metal plates such as aluminum plates and stainless steel plates, and drum-shaped items.

(2) A thin layer of metal such as aluminum, palladium, or gold is provided on a support such as paper or plastic film by lamination or vapor deposition.

(3) A layer of a conductive compound such as a conductive polymer, indium oxide, or tin oxide is provided on a support such as paper or a plastic film by coating or vapor deposition.

Formation of constituent layers such as a carrier transport layer and a carrier generation layer according to the present invention includes vacuum evaporation, sputtering, and CVD.
A vapor deposition method such as , or a coating method such as dipping, spraying, blade, or roll method may be arbitrarily used.

The photoreceptor of the present invention has the above-mentioned structure, and has excellent charging characteristics, sensitivity characteristics, and image forming characteristics, as is clear from the examples described below. In particular, it exhibits excellent durability with little fatigue deterioration even when subjected to repeated transfer electrophotography.

〔Example〕

Examples of the present invention will be specifically described below, but the embodiments of the present invention are not limited thereby.

Example 1 A conductive support formed by vapor-depositing aluminum on a polyester film was coated with a film made of vinyl chloride-vinyl acetate-maleic anhydride copolymer [Suresoku MF-10J (manufactured by Tanezu Kagaku Co., Ltd.) with a thickness of 0.5 mm. A 1 μm intermediate layer was provided.

On top of that, 1 part by weight of dibrome anthronate represented by the following structural formula [Monolite Trend 2 YJ (IC1 Company M)] and polycarbonate resin "Panlite L-1250" were added.
J (manufactured by Ondai Kasei Co., Ltd.) in 100 parts by weight of 1,2-dichloroethane and dispersed in a ball mill for 24 hours. The liquid was applied to a carrier so that the film thickness after drying was lpm. A generation layer was formed.

Exemplary compound (1)7.
5 parts by weight and polycarbonate resin "Panlite L-1"
250J 10 parts by weight and 1,2-dichloroethane 80
The electrophotographic photoreceptor of the present invention was prepared by coating a solution dissolved in parts by weight so that the film thickness after drying was 20 μm to form a carrier transport layer.

Regarding this electrophotographic photoreceptor, the electrostatic copying paper tester rE
The electrophotographic properties were measured using a Dynamink method using PA-8100J (Kawaguchi Electric Seisakusho).

That is, the surface potential VA when the surface of the photosensitive layer of the photoreceptor is charged for 5 seconds at a charging voltage of -6 KV, and then the light from the tungsten lamp is applied to the surface of the photoreceptor so that the illuminance of the photoreceptor surface becomes 3.5 (lux). irradiated to increase the surface potential from -600V to -11
Exposure amount (sensitivity) required to attenuate to 00v E, ::
, and the surface potential (residual potential) VR after irradiation with an exposure amount of 30 Qux-sec were determined.

Further, similar measurements were repeated 100 times. Result is,
As shown in Table 1.

Comparative Example (1) A comparative photoreceptor (1) was prepared in the same manner as in Example 1, except that a stilbene derivative represented by the following structural formula was used as a carrier transport substance, and the same measurements as in Example 1 were carried out. Ta.

The results are shown in Table 1.

As is clear from the results in Table 1 and above, the electrophotographic photoreceptor of the present invention of Example 1 was significantly superior to the photoreceptor of Comparative Example (1) in terms of sensitivity, residual potential characteristics, and repeated stability. It is.

Examples 2-10 Exemplary compounds (2) and (4) as carrier transport substances.

(6), (8), (10), (12), (14), (1
An electrophotographic photoreceptor of the present invention was prepared in the same manner as in Example 1 using 6) and (18). Measurements were performed on these electrophotographic photoreceptors in the same manner as in Example 1.

The results are shown in Table 2.

Table 2 Example 11 1 part by weight of a bisazo pigment represented by the following structural formula and polymethyl methacrylate-1 resin "Dianal" were placed on a conductive support consisting of a polyester film laminated with aluminum foil. 0.5 parts by weight of BR-80J (manufactured by Mitsubishi Rayon Co., Ltd.) was added to 100 parts by weight of 1,2-dichloroethane and dispersed for 4 hours using a sand grinder.The resulting solution was coated so that the film thickness after drying was 0.4 μm. A carrier generation layer was formed.

Next, Exemplified Compound (3) 7.5 as a carrier transport substance
Weight parts and polycarbonate resin "Panlite K-13"
A solution prepared by dissolving 10 parts by weight of 004 (manufactured by Ryotai Kasei Co., Ltd.) in 100 parts by weight of 1,2-dichloroethane is coated so that the film thickness after drying is 20 μm to form a carrier transport layer. A photographic photoreceptor was created.

This electrophotographic photoreceptor was measured in the same manner as in Example 1, and the results shown in Table 3 were obtained.

Comparative Example (2) A comparative photoreceptor (2) was prepared in the same manner as in Example 11 using a stilbene derivative represented by the following structural formula as a carrier transporting substance. When this comparative photoreceptor was measured in the same manner as in Example 1, the results shown in Table 3 were obtained.

As is clear from the above results, the electrophotographic photoreceptor of the present invention of Example 11 is significantly superior to the comparative photoreceptor in terms of sensitivity, residual potential, and repetition stability.

Example 12 A conductive support formed by vapor-depositing aluminum on a polyester film was coated with vinyl chloride-vinyl acetate-maleic anhydride 11 substance r Esresoku MF-10J with a thickness of 0.
1. An intermediate layer of un was provided.

On top of that, 1 part by weight of a bisazo pigment represented by the following structural formula as a carrier generating substance and 5 parts by weight of polycarbonate resin [Panlite K-1300J O] were added to 100 parts by weight of Tetrahydro 7ran and dispersed in a ball mill for 24 hours. A carrier generation layer was formed by applying the following to a dry film thickness of 0.4 μm.

Next, an exemplified compound (5) was added thereon as a carrier transport substance.
) 7.5 parts by weight and polycarbonate resin [Panlite K
-10 parts by weight of 1300J and 1 part by weight of tetrahydrofuran
An electrophotographic photoreceptor of the present invention was prepared by applying a solution dissolved in 0.00 parts by weight so that the film thickness after drying was 20 μm.

When this electrophotographic photoreceptor was measured in the same manner as in Example 1, the results shown in Table 4 were obtained.

Example 13 An electrophotographic photoreceptor of the present invention was prepared in the same manner as in Example 12, except that a hisazo pigment represented by the following structural formula was used as a carrier-generating substance.

When this electrophotographic photoreceptor was measured in the same manner as in Example 1, the results shown in Table 4 were obtained.

Table 4 Example 14 A 0.1 μm thick intermediate layer made of vinyl chloride-vinyl acetate-maleic anhydride copolymer "S-LEC MF-10J" was coated on a cylindrical aluminum drum with a diameter of 80 mm by a dipping method.

On top of that, 1 part by weight of Dibrom Anthron "Monolite Red 2YJ and 1 part by weight of polycarbonate resin [Panlite L-1250J] were mixed in 100 parts by weight of 1,2-dichloroethane, and the liquid was dispersed in a ball mill for 24 hours using a dipping method. A carrier generation layer having a film thickness of 1 μm was formed by coating.

Furthermore, exemplified compound (2) is added as a carrier transport substance.
7.5 mff 1 part and polycarbonate resin rZ-200J shown by the following structural formula (manufactured by Mitsubishi Gas Chemical Co., Ltd.)
A solution prepared by dissolving 10 parts by weight of the
An electrophotographic photoreceptor of the present invention was prepared by forming a carrier transport layer with a thickness of 0 μm.

This electrophotographic photoreceptor is used in an electrophotographic copying machine ro-Bix15.
When the image was copied by attaching it to a 50MRJ, a copied image was obtained that was faithful to the original, had high contrast, and had excellent gradation. Even after repeating this process 50,000 times, a copy image similar to the initial one was obtained.

Comparative Example (3) A comparative photoreceptor (3) was prepared in the same manner as in Example 14, except that a hydrazone derivative represented by the following structural formula was used as a carrier transport substance.

When images were copied using this comparative photoreceptor in the same manner as in Example 14, a good copy image was initially obtained as in Example 14, but fogging began to become noticeable around 15,000 copies and after 20,000 copies. However, only images with a lot of fog and reduced contrast could be obtained.

Example 15 A 0.1 μm thick intermediate layer made of vinyl chloride-hinyl acetate-maleic anhydride copolymer "S-LEC MF-10" was provided on a conductive support made of a polyester film laminated with aluminum foil.

Next, an exemplary compound (7) was added thereon as a carrier transport substance.
) 7.5 parts by weight and polycarbonate resin "Panlite L"
-1250J dissolved in 80 parts by weight of 1,2-dichloroethane was applied to form a carrier transport layer so that the film thickness after drying was 20 μm.

Furthermore, a carrier generating substance 1 represented by the following structural formula is added thereto.
Exemplary compound (7) as part by weight and carrier transport substance
1.5 ffNt parts, 2 parts by weight of polycarbonate resin [Panlite L-, 1250J] were added to 100 parts by weight of 1,2-dichloroethane, and the resulting solution was dispersed in a ball mill for 24 hours to form a carrier with a film thickness of 3 μm after drying. An electrophotographic photoreceptor of the present invention was prepared by forming the layers.

This electrophotographic photoreceptor was measured in the same manner as in Example 1, except that the charging voltage was changed to +6 kV, and the results shown in Table 5 were obtained.

Comparative Example (4) A comparative photoreceptor was prepared in the same manner as in Example 15, except that a stilbene derivative represented by the following structural formula was used as the carrier transport substance.

When this comparative photoreceptor was measured in the same manner as in Example 15, the results shown in Table 5 were obtained.

As is clear from the results in Table 5 and above, the electrophotographic photoreceptor of the present invention has extremely superior characteristics in terms of sensitivity and repeated stability compared to the comparative photoreceptor.

Example 16 An intermediate layer having a thickness of 0.1 μm consisting of a hinyl chloride-hinyl acetate-maleic anhydride copolymer [ESRESOC MF-10J] was provided on a polyester film on which aluminum was vapor-deposited.

On top of that, 1 part by weight of hisazo pigment represented by the following structural formula as a carrier transport substance and 5 parts by weight of polycarbonate resin "Panrye I-L-1250J O.
A carrier generation layer was formed by applying a solution prepared by adding 100 parts by weight of dichloroethane and dispersing it in a ball mill for 24 hours so that the film thickness after drying was 0.3 μm.

Furthermore, exemplified compound (9) is added as a carrier transport substance.
7.5 parts by weight and polycarbonate resin [Panrye l-K
-1300J 10 parts by weight dissolved in 100 parts by weight of 1,2-dichloroethane has a film thickness of 16 μm after drying.
The electrophotographic photoreceptor of the present invention was prepared by coating the powder to form a carrier transport layer.

When this electrophotographic photoreceptor was measured in the same manner as in Example 1, the results shown in Table 6 were obtained.

Table 6 Example 17 1 part by weight of a carrier-generating substance represented by the following structural formula and a polyester resin [Vylon 200J (manufactured by Toyobo Co., Ltd.) 05] on a polyester film on which aluminum was vapor-deposited
parts by weight were added to 100 parts by weight of 1,2-dichloroethane and dispersed in a ball mill for 24 hours, and the solution was coated to a thickness of 05 μm.
A carrier generation layer was formed.

Furthermore, an exemplary compound (11) is added thereon as a carrier transport substance.
) 7.5 parts by weight of polycarbonate resin
-K -1300J 10 parts by weight dissolved in 100 parts by weight of 1,2-dichloroethane was applied to a thickness of 15 μm.
A carrier transport layer was formed to prepare an electrophotographic photoreceptor of the present invention.

When this electrophotographic photoreceptor was measured in the same manner as in Example 1, the results shown in Table 7 were obtained.

Comparative Example (5) Example 17 except that 7.5 parts by weight of a stilbene derivative (A) represented by the following structural formula was used as a carrier transport substance.
A comparison photoreceptor (5) was prepared in the same manner as described above.

When this comparative photoreceptor was measured in the same manner as in the examples, the results shown in Table 7 were obtained.

Stilbene derivative (A) Table 7 Example 18 A carrier generation layer was formed in the same manner as in Example 11, except that metal-free -7 lysyanine (manufactured by Toyo Ink Co., Ltd.) was used as the carrier generation substance.

Next, Exemplified Compound (2) 4.0 as a carrier transport substance
A carrier transport layer was formed in the same manner as in Example 11 except that parts by weight were used to obtain a photoreceptor of the present invention.

When this electrophotographic photoreceptor was measured in the same manner as in Example 1, the results shown in Table 8 were obtained.

As is clear from the results in Table 8 and above, the electrophotographic photoreceptor of the present invention is significantly superior in sensitivity, residual potential characteristics, and repetition stability compared to the comparative photoreceptor.

[Brief explanation of the drawing]

1 to 6 are sectional views showing examples of the mechanical structure of the photoreceptor of the present invention, respectively. 1 L... Conductive support 2... Carrier generation layer 3... Carrier transport layer 4... Photosensitive layer 5... Intermediate layer 6... ...Layer 7 containing a carrier transport substance...
...Carrier generating substance 8...Protective layer

Claims (1)

[Scope of Claims] An electrophotographic photoreceptor comprising a photosensitive layer containing at least one triarylamine derivative represented by the following general formula [I] on a conductive support. General formula [I] ▲There are mathematical formulas, chemical formulas, tables, etc.▼ [However, in the formula, Ar_1 and Ar_2 represent a substituted or unsubstituted aryl group, Ar_3 represents a substituted or unsubstituted arylene group, R_3, R_4, R_5, R
_6, R_7, and R_8 may each be the same or different, and are hydrogen atom, halogen atom, substituted or unsubstituted alkyl group, substituted or unsubstituted alkoxy group, substituted or unsubstituted aryl group, substituted or unsubstituted represents an aryloxy group or a substituted amino group. X represents an oxygen atom, a sulfur atom, or >N-R_9 (R_9 represents a hydrogen atom or a substituted or unsubstituted alkyl group). ]