JPH0815879A - Electrophotographic photoreceptor - Google Patents

Abstract

PURPOSE:To obtain the electron transfer performance, high sensitivity, low residual potential and good image-holding property of an electrophotographic photoreceptor having a photosensitive layer on a conductive supporting body by incorporating a specified compd. into the photosensitive layer. CONSTITUTION:In this electrophotographic photoreceptor having a photosensitive layer on a conductive supporting body, the photosensitive layer contains a compd. expressed by formula. As for the conductive supporting body, for example, a metallic pipe, metallic plate, metallic sheet, metallic foil, polymer film treated to have conductivity, polymer film having a metal vapor deposition layer such as Al, or polymer film or paper coated with metal oxides, quaternary ammonium salt or the like are used. The photosensitive layer is formed on the conductive supporting body and may be formed into a single layer or a laminated structure whose functions are separated into a charge producing layer and a charge transfer layer. Or an adhesive layer may be formed between the conductive supporting body and the photosensitive layer. Further, if necessary, a protective layer may be formed on the photosensitive layer.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to an electrophotographic photosensitive member for forming an electrostatic latent image. More specifically, it relates to an electrophotographic photoreceptor having a layer containing a compound having an electron transporting ability.

[0002]

2. Description of the Related Art Conventionally, electrophotographic photoreceptors using organic photoconductors have been variously studied because of their advantages such as pollution-free, high productivity and low cost. It has been put to practical use as a photoconductor. These electrophotographic photoreceptors include a laminated type and a single layer type, but a photoreceptor using an organic photoconductor generally has a charge generation layer that generates a charge by light irradiation and a charge that transports the generated charge. It has a laminated structure consisting of a transport layer. In this case, as the charge transport material used in the charge transport layer, a polymer material such as poly-N-vinylcarbazole or a low molecular weight compound such as pyrazoline, hydrazone or triphenylamine derivative is used.

However, since all of these charge-transporting substances have a hole-transporting ability, most of the developing systems adopting a negative charge on the surface of the photoconductor are adopted. For this reason, the toner that was conventionally used in high-speed machines cannot be used,
Currently, there are few high-quality images. Further, when the surface of the photoconductor is negatively charged as described above, there is a problem that not only the ozone is generated due to the reaction with oxygen in the air at the time of charging to harm the environment but also the surface of the photoconductor is deteriorated.

On the other hand, a positive charging laminated photoreceptor having a charge transport layer on the lower side and a charge generation layer on the upper side has been developed by reversing the layer structure of the photosensitive layer of the laminated photoreceptor. Since the charge generation layer, which has a low charging potential and is usually 2 to 3 μm or less, which is relatively thin, is the upper layer, even a slight scratch or the like appears as a failure, and the printing durability becomes poor, so the charge generation layer is deteriorated. There is no choice but to adopt a structure in which a protective layer is further provided on the above. However, since the provision of the protective layer hinders the movement of charges and deteriorates the photographic characteristics of the photoconductor, the practical situation has not been found yet.

[0005]

In order to solve the above problems, a photoconductor in which a charge transport material having an electron transporting property is used in a charge transport layer and the surface of the photoconductor is positively charged. Should be configured. 2,4,7-Trinitro-9-fluorenone is known as such an electron-transporting material, but its solubility is poor and it is not possible to obtain practical sensitivity by combining it with an existing charge-generating substance. It was In addition, 2, 4,
As a result of improved studies on 7-trinitro-9-fluorenone, in recent years, an electron transporting substance having a solubilizing group introduced into an electron acceptor structure has been proposed. For example, Japanese Patent Laid-Open No. 1-206349
No. 2-135362, No. 2-214866, No. 3-290666 and “Japan Hardcopy '92” Proceedings, 173, (1992).

However, when any of the compounds is combined with an existing charge generating substance to form a photoconductor, the sensitivity is still insufficient in practical use, and a good image cannot be obtained under the present circumstances.

In view of the above problems, it is an object of the present invention to provide an electrophotographic photosensitive member using a charge transporting substance having an electron transporting ability.

Another object of the present invention is to provide a positive charging electrophotographic photosensitive member having excellent electrophotographic performance, that is, high sensitivity, low residual potential and good image characteristics.

[0009]

As a result of research, the present inventors have found that the object of the present invention can be achieved by any of the following electrophotographic photoreceptors. That is, (1) an electrophotographic photoreceptor having a photosensitive layer provided on a conductive support, wherein the photosensitive layer contains a compound represented by the following general formula [A].

[0010]

[Chemical 7]

(2) The electrophotographic photosensitive member according to claim 1, wherein the compound represented by the general formula [A] is a compound represented by the following general formula [a].

[0012]

Embedded image

(3) An electrophotographic photoreceptor having a photosensitive layer provided on a conductive support, wherein the photosensitive layer contains a compound represented by the following general formula [B].

[0014]

[Chemical 9]

(4) The electrophotographic photosensitive member according to claim 3, wherein the compound represented by the general formula [B] is a compound represented by the following general formula [b].

[0016]

[Chemical 10]

(5) An electrophotographic photoreceptor having a photosensitive layer provided on a conductive support, wherein the photosensitive layer contains a compound represented by the following general formula [C].

[0018]

[Chemical 11]

(6) The electrophotographic photosensitive member according to claim 5, wherein the compound represented by the general formula [C] is a compound represented by the following general formula [c].

[0020]

[Chemical 12]

The high performance of the charge transport material of the present invention is
It seems that the long-term compatibility with the binder is kept stable as compared with the conventional charge transport material.

Next, specific examples of the compounds represented by the above general formula and synthetic examples thereof will be shown.

(A) Compound represented by the general formula [A]: Exemplified compound:

[0024]

[Chemical 13]

[0025]

Embedded image

[0026]

[Chemical 15]

[0027]

Embedded image

[0028]: Synthesis example:

[0029]

[Chemical 17]

Raw material 1 is a known method (R. Neidlein et al .: Che
m.Ber.115, 2898 (1982)) (melting point: 350 ° C or higher).

Well ground compound 1: 10.0 g (0.045 m
ol) is placed in a sufficiently dried four-liter four-necked flask, 650 ml of dehydrated chloroform (manufactured by Kanto Chemical Co., Inc.) is added, and stirring is started. Titanium tetrachloride (9.9 ml, 0.09 mol) was added dropwise, followed by cooling to -45 ° C with dry ice-acetone, and cyano-t-butyl acetate 2: 8.2 g (manufactured by Aldrich).
(0.06mol) and dehydrated pyridine (Kanto Chemical Co., Inc.) 36.3ml
A 350 ml solution of dehydrated chloroform in 1 is added dropwise while maintaining the internal temperature at -40 ° C ± 5 ° C. Subsequently, the internal temperature was kept at -10 ° C or lower with a saline bath, and the mixture was stirred for 12 hours. As a post-treatment, 250 ml of well-cooled ether is added to the reaction solution to precipitate crystals. After suction filtration, it is washed 3 times with 200 ml of ether, 3 times with 200 ml of water, and 3 times with 60 ° C.-200 ml of hot water, and then dried under reduced pressure at 100 ° C.

The crude crystals are purified by recrystallization and sublimation,
The target exemplified compound K _A -4: 9.7 g (0.028 mol) was successfully obtained with a yield of 62%.

The structure was confirmed by the fact that the FD-MASS spectrum shows 347 as M ⁺ and that the elemental analysis values agree well with the calculated values (below). The melting point was 290 ° C.

[0034] (B) Compound represented by General Formula [B]: Exemplified compound:

[0035]

Embedded image

[0036]

[Chemical 19]

[0037]

Embedded image

[0038]

[Chemical 21]

[0039]

[Chemical formula 22]

: Synthesis example:

[0041]

[Chemical formula 23]

20 g (0.076 mol) of 2-t-butylanthraquinone 1 (manufactured by Aldrich) was placed in a 1-liter four-headed flask, 400 ml of dehydrated acetonitrile (manufactured by Kanto Chemical Co., Ltd.) was added, and 1,3-under a stream of N _2. 18.4 g (0.099 mol) of bis (trimethylsilyl) carbodiimide 2 (manufactured by Aldrich) and a little cesium fluoride were added, and the mixture was stirred for 20 hours. Post-processing is
The reaction solution was concentrated under reduced pressure, and the precipitated crystals were collected by suction filtration and dried under reduced pressure to give 15.2 g of yellow crystals. The crystal column purification, and recrystallization, a mixture of K _B -1 and K _B -3 of interest 9.
Obtained in 0 g (0.031 mol) yield of 41%.

The structure was confirmed by showing 288 peaks of M ^{+ in} the FD-MASS spectrum and the fact that the elemental analysis values agree well with the calculated values (below). Note that K _B -1 and K _B -3
The ratio of was not known from the NMR spectrum. The melting point was 147-149 ° C.

[0044] (C) Compound represented by general formula [C]: Exemplified compound:

[0045]

[Chemical formula 24]

[0046]

[Chemical 25]

[0047]

[Chemical formula 26]

[0048]

[Chemical 27]

: Synthesis example:

[0050]

[Chemical 28]

(Synthesis of Intermediate 3) Raw material 1 was synthesized by a known method (R. Neidlein et al .: Chem. Ber. 115, 2898 (1982)) (melting point: 350 ° C. or higher).

Well ground compound 1: 10.0 g (0.045 m
ol) is placed in a sufficiently dried four-liter four-necked flask, 650 ml of dehydrated chloroform (manufactured by Kanto Chemical Co., Inc.) is added, and stirring is started. Titanium tetrachloride (9.9 ml, 0.09 mol) was added dropwise, followed by cooling to -45 ° C. with dry ice-acetone, and cyano-t-butylacetone (Aldrich) 2: 8.2 g
(0.06mol) and dehydrated pyridine (Kanto Chemical Co., Inc.) 36.3ml
A 350 ml solution of dehydrated chloroform in 1 is added dropwise while maintaining the internal temperature at -40 ° C ± 5 ° C. Subsequently, the internal temperature was kept at -10 ° C or lower with a saline bath, and the mixture was stirred for 12 hours.

As a post-treatment, well-cooled ether 25 was used.
0 ml is added to the reaction solution to precipitate crystals. 2 after suction filtration
Wash 3 times with 00 ml of ether, 3 times with 200 ml of water, 3 times with 200 ml of hot water (60 ° C), and dry under reduced pressure at 100 ° C.

The crude crystals were purified by recrystallization and sublimation, and succeeded in obtaining the intended intermediate 3: 9.7 g (0.028 mol) in a yield of 62%.

The structure was confirmed by the fact that the FD-MASS spectrum shows 347 as M ⁺ and that the elemental analysis values agree well with the calculated values (below). The melting point was 290 ° C.

[0056] (Synthesis of Exemplified Compound K _C -1) Intermediate 3: 8.0 (0.023mo
l) was placed in a 500 ml four-headed flask, 200 ml of dehydrated acetonitrile (manufactured by Kanto Chemical Co., Inc.) was added, and 1,3-bis was added under a stream of N _2.
(Trimethylsilyl) carbodiimide 4 (manufactured by Aldrich) 8.6 g (0.046 mol) and a little cesium fluoride were added, and 1
Stir for 0 hours.

For the post-treatment, the reaction solution was concentrated under reduced pressure, and the precipitated crystals were collected by suction filtration and dried under reduced pressure to obtain 7.0 g of a crudely purified product. Column purification and recrystallization of this crystal gives the desired K _C
5.3 g (0.015 mol) of -1 crystal was obtained with a yield of 65%.

The structure was confirmed by showing an M ⁺ 357 peak in the FD-MASS spectrum and the fact that the elemental analysis values agree well with the calculated values (below). The melting point was 192-194 ° C.

[0059] In the electrophotographic photosensitive member of the present invention, as the conductive support, for example, a metal pipe, a metal plate, a metal sheet, a metal foil,
A conductive polymer film, a polymer film provided with a vapor deposition layer of a metal such as Al, a polymer film coated with a metal oxide, a quaternary ammonium salt, or the like, or paper is used.

In the electrophotographic photosensitive member of the present invention, the photosensitive layer is provided on the conductive support, but the photosensitive layer may have a single layer structure, or a laminated structure in which the charge generating layer and the charge transporting layer are functionally separated. It may be one. An adhesive layer may be provided between the conductive support and the photosensitive layer.

As shown in FIGS. 1 (a) and 1 (b), the photoconductor of the present invention comprises a charge generating substance (CG) on a conductive support 1.
M) as the main component of the charge generation layer (CGL) 2 and the charge transport material (CTM) as the main component of the charge transport layer (C)
A photosensitive layer 4 composed of a laminate with TL) 3 is provided. The photosensitive layer 4 may be provided via an intermediate layer 5 provided on the conductive support 1, as shown in FIGS. Thus, when the photosensitive layer 4 has a two-layer structure, a photoreceptor having the most excellent electrophotographic characteristics can be obtained. In addition, in the present invention, as shown in FIGS.
The photosensitive layer 4 formed by dispersing fine particle-shaped CGM 7 in the layer 6 containing as a main component is provided directly on the conductive support 1 or the intermediate layer 5
You may provide through.

Further, a protective layer (OCL) may be provided on the photosensitive layer 4 if necessary.

CGL which constitutes the photosensitive layer 4 having a two-layer structure
2, CTL3 can be formed by the following method depending on the characteristics of CTM and CGM, directly on the conductive support 1, which is the lower layer surface, or after providing an intermediate layer such as an adhesive layer or a barrier layer if necessary. it can.

(1) Vapor deposition method (2) Coating method a) Method of applying a solution coating in which CGM and CTM are dissolved in a suitable solvent b) CGM and CTM are finely dispersed in a dispersion medium by a ball mill, homomixer or the like. A method of applying a dispersion coating material obtained by mixing and dispersing it into particles and, if necessary, a binder.

Examples of the vapor deposition method include a vacuum vapor deposition method, a sputtering method, an ion plating method, a CVD method, and the like, and a paint coating method includes a dipping method, a spray method, an air doctor method, a doctor blade method, and a reverse method. An appropriate method is selected according to the physical properties of the coating material such as the roll method.

The adhesive layer is formed of resin alone, coated with a low resistance compound such as tin oxide, indium oxide, or titanium oxide dispersed in resin, or aluminum oxide, zinc oxide, silicon oxide, or the like. The vapor deposition film of
The resin used for the adhesive layer is not particularly limited, and examples thereof include vinylidene chloride-vinyl chloride copolymer, water-soluble polyvinyl butyral resin, alcohol-soluble polyamide resin, vinyl acetate-based resin, polyvinyl alcohol, nitrocellulose, and polyimide resin. To be

The thickness of the binder layer is preferably about 0.01 to 10 μm, and particularly preferably 0.01 to 1 μm.

When the photosensitive layer is a single layer, the compound represented by the above general formulas [A] to [C] is contained as a sensitizer in the photosensitive layer composed of a known material such as polyvinylcarbazole. Or a photosensitive layer containing a known charge generating substance containing the compounds represented by the above formulas [A] to [C] as an electron transporting substance.

On the other hand, when the photosensitive layer is a laminated type,
The charge generation layer may be obtained by vapor deposition of a charge generation substance on a conductive support, or may be formed by applying a coating liquid containing a charge generation substance and a binder resin as main components.

Any known charge generating substance and binder resin can be used.

For example, as the charge generating substance, an inorganic semiconductor such as Te-Se, an organic semiconductor such as polyvinylcarbazole, a bisazo compound, a trisazo compound, a metal-free phthalocyanine compound, a metal phthalocyanine compound,
Organic pigments such as pyrylium compounds, squarylium compounds, cyanine compounds, perylene compounds and polycyclic quinone compounds can be used. Among them, preferable charge generating substances include, for example, Y-type titanyl phthalocyanine pigments having an X-ray diffraction peak at 27.2 ° in JP-A-64-17066,
A having an X-ray diffraction peak at 26.3 ° in JP-A-62-67094
Type titanyl phthalocyanine pigment, B type titanyl phthalocyanine pigment having an X-ray diffraction peak at 28.7 ° of JP-A-61-239248, metal-free phthalocyanine pigment of JP-B-49-4338, and copper phthalocyanine of JP-A-57-163239. Pigments, vanadyl phthalocyanine pigments of JP-A-57-148747, perylene pigments of JP-A-49-128734, condensed polycyclic pigments of JP-A-47-18544, and bisazo pigments of JP-A-1-150145. . As the binder resin, polystyrene, silicone resin, polycarbonate resin, acrylic resin, methacrylic resin, polyester, vinyl polymer, cellulose resin, butyral resin, silicone modified butyral resin, alkyd resin and the like can be used.

The thickness of the charge generation layer is preferably about 0.01 to 10 μm, particularly preferably 0.05 to 2 μm.

A charge transport layer is formed on the charge generation layer. The charge transport layer comprises a compound represented by the above general formulas [A] to [C] and a binder resin,
A coating solution containing the compounds represented by the above general formulas [A] to [C], a binder resin, and a suitable solvent as main components is applied onto the charge generation layer by an applicator, a bar coater, a dip coater, or the like. Formed by. In this case, the mixing ratio of various compounds and the binder resin is preferably 1: 100 to 100: 1, and particularly preferably 1:20 to 20: 1.

As the charge transport material and the binder resin used in the charge transport layer, any known materials can be used. For example, as the binder resin, acrylonitrile
-Butadiene copolymer, styrene-butadiene copolymer,
Vinyltoluene-styrene copolymer, styrene-modified alkyd resin, silicone-modified alkyd resin, soybean oil-modified alkyd resin, vinylidene chloride-vinyl chloride resin,
Polyvinyl butyral, nitrated polystyrene, polymethylstyrene, polyisoprene, polyester, phenol resin, Kent resin, polyamide, polycarbonate, polythiocarbonate, polyacrylate, polyhaloacrylate, vinyl acetate resin, polystyrene, polyallyl ether, polyvinyl Acrylate, polysulfone, polymethacrylate, etc. may be mentioned. Among them, biphenyl Z type polycarbonate is particularly preferable. Further, an electron-donating substance may be added to the charge transport layer to produce a bipolar photoreceptor.

Further, an antioxidant or a radical trap agent may be added to the charge transport layer.

The thickness of the charge transport layer is preferably 2 to 100 μm, particularly preferably 5 to 50 μm.

In the electrophotographic photosensitive member of the present invention,
A barrier layer may be provided on the conductive support. The barrier layer is
It is effective in preventing the injection of unnecessary charges from the conductive support and has the effect of improving the image quality. Materials for forming the barrier layer include metal oxide such as aluminum oxide, acrylic resin, phenol resin, polyester resin, polyurethane and the like. The barrier layer may be provided on the adhesive layer or may be provided on the upper side.

[0078]

EXAMPLES Next, the present invention will be specifically described by way of examples. In addition, "parts" in the present examples means "parts by weight".

[1] Examples of Compound Represented by General Formula [A] (I) Evaluation of Sensitivity Evaluation 1 Examples 1 to 3 Polyamide resin “CM8000” (manufactured by Toray Industries, Inc.) on a PET film on which aluminum was vapor deposited. An intermediate layer having a thickness of 0.5 μm is provided, and a perylene pigment G-shown in “Chemical Formula 29” is formed thereon.
1: 1 part, polyvinyl butyral resin "ESREC BL
S "(manufactured by Sekisui Chemical Co., Ltd.) and 50 parts of methyl ethyl ketone as a dispersion medium dispersed in a sand mill were applied using a wire bar to form a charge generation layer having a thickness of 0.3 μm. Next, 1 part of the exemplified compound shown in Table 1 and 1.5 parts of a polycarbonate resin "Iupilon Z-200" (manufactured by Mitsubishi Gas Chemical Co., Inc.) are dissolved in 10 parts of tetrahydrofuran (hereinafter abbreviated as THF) and blade-coated on the charge generation layer. As a result, a charge transport layer having a thickness of 20 μm was formed.

Comparative Example 1 A comparative sample was prepared in the same manner as in Example 1 except that Comparative Compound 1 shown in “Chemical Formula 29” was used instead of the exemplified compound.

Electrophotographic Photosensitive Samples Obtained in Example 1 and Comparative Example 1 Electrostatic Copy Paper Testing Apparatus EPA
Using -8100 (manufactured by Kawaguchi Denki Co., Ltd.), it was charged to +800 V and exposed to 10 lux of white light, and the exposure amount until the surface potential was halved was determined to obtain the sensitivity. The results are shown in Table 1.

(II) Durability Evaluation Examples 4 to 6 A 0.5 μm-thick intermediate layer made of polyamide resin “X-1874M” (manufactured by Daicel Hüls) was provided on a PET film on which aluminum was vapor deposited. 1 part of pigment X type metal-free phthalocyanine (manufactured by Dainippon Ink and Chemicals, Inc.), 0.4 part of polyvinyl butyral resin "ESREC BX-1" (manufactured by Sekisui Chemical Co., Ltd.), and methyl isopropyl ketone 50 as a dispersion medium.
The liquid in which the parts were dispersed using a sand mill was applied using a wire bar to form a charge generation layer having a thickness of 0.3 μm. Next, 1 part of the exemplified compound in Table 2 and 1.5 parts of polycarbonate resin "Iupilon Z-200" (manufactured by Mitsubishi Gas Chemical Co., Inc.) were dissolved in 10 parts of THF, and blade coating was performed on the charge generation layer to obtain a film thickness of 20 μm.
Was formed on the charge transport layer.

Comparative Example 2 A comparative sample was prepared in the same manner as in Example 31 except that Comparative Compound 2 shown in "Chemical Formula 29" was used in place of the exemplified compound.

Evaluation 2 The electrophotographic photoreceptor samples obtained in Examples 4 to 6 and Comparative Example (2) were subjected to the following actual measurement values with an U-BIX 1017 remodeling machine manufactured by Konica Corporation at the initial stage and after copying 10,000 sheets. evaluated. Table 2 shows the results.

Vb: Black part potential, Vw: White part potential,
Vr: Residual potential (III) Image quality evaluation Examples 7 to 9 An intermediate layer made of polyamide resin “CM8000” (manufactured by Toray Industries, Inc.) having a thickness of 0.5 μm was provided on a cylindrical aluminum substrate, and a Bragg in X-ray diffraction was provided thereon. Angle 2θ 9.5 °, 24.1 °, 27.
A liquid in which 1 part of titanyl phthalocyanine having a peak at 2 °, 0.5 part of silicone-butyral resin and 50 parts of methyl isopropyl ketone as a dispersion medium were dispersed using a sand mill was dip-coated to form a charge generation layer having a thickness of 0.3 μm.

Next, 1 part of the exemplified compounds shown in Tables 7 to 9 and 1.5 parts of polycarbonate resin "Iupilon Z-200" (manufactured by Mitsubishi Gas Chemical Co., Inc.) were dissolved in 10 parts of THF, and dip-coated on the charge generation layer to obtain a film thickness. A 20 μm charge transport layer was formed.

Comparative Example 3 A comparative sample was prepared in the same manner as in Example 61 except that Comparative Compound 3 shown in "Chemical Formula 29" was used in place of the exemplified compound.

Evaluation 3 The electrophotographic photoreceptor samples obtained in Examples 7 to 9 and Comparative Example 3 were subjected to a digital copying machine "Konica 9028" modified by Konica Corporation (changed to positive charging property, reverse development). Images were displayed. These samples were then placed at low temperature (10
(° C.) environment was left for 1 month, and then images were reproduced again under the same conditions. The black spots on the white background portion of these copied images were evaluated. The results are shown in Table 3.

The evaluation of black spots was carried out by measuring the size and number of black spots using an image analyzer "Omnicon 300 type" (manufactured by Shimadzu Corporation), and a black spot having a diameter of 0.05 mm or more was 1 cm ^2.
It was performed by judging how many there are. The criteria for evaluating the black spots are as shown below. It should be noted that if the result of the black spot determination is ⊚ and ◯, it is practical, but Δ is not suitable for practical use, and if it is ×, it is not suitable for practical use.

Number of black spots with a diameter of 0.05 mm or more (pieces / cm ² ) Black spot determination 0 ◎ 1-3 ○ 4-10 △ 11 or more ×

[0091]

[Chemical 29]

[0092]

[Table 1]

[0093]

[Table 2]

[0094]

[Table 3]

As is clear from the above-mentioned tables, the electrophotographic photosensitive member using the charge transporting material of the present invention has higher sensitivity and repeatability than the conventional charge photographic photosensitive member using the charge transporting material. The characteristics of the photoconductor during use are stable, and
It can be seen that the occurrence of image defects is extremely small even after storage at low temperature.

[2] Examples of Compound Represented by General Formula [B] The sensitivity, durability and image quality were evaluated in the same manner as in the case of the general formula [A].

(I) Sensitivity Evaluation Examples 10 to 12 Comparative Example 4 Table 4 (II) Durability Evaluation Examples 13 to 15 Comparative Example 5 Table 5 (III) Image Evaluation Examples 16 to 18 Comparative Example 6 Table 6 The comparative compounds used and the test results are shown below.

[0098]

Embedded image

[0099]

[Table 4]

[0100]

[Table 5]

[0101]

[Table 6]

[3] Examples of Compound Represented by General Formula [C] The following evaluation tests were conducted in the same manner as in the case of the general formulas [A] and [B].

(I) Sensitivity Evaluation Examples 19 to 21 Comparative Example 7 Table 7 (II) Durability Evaluation Examples 22 to 24 Comparative Example 8 Table 8 (III) Image Evaluation Examples 25 to 27 Comparative Example 9 Table 9 The comparative compounds used and the test results are shown below.

[0104]

[Chemical 31]

[0105]

[Table 7]

[0106]

[Table 8]

[0107]

[Table 9]

As is clear from the results of the above [2] and [3], the compounds of the general formulas [B] and [C] also show good properties like the compounds of the general formula [A].

[0109]

EFFECT OF THE INVENTION The compound of the present invention can provide a photoconductor for positive charging which has an electron transporting ability and is practical, that is, has high sensitivity, low residual potential, and good image retention.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of an exemplary embodiment of a photoconductor of the present invention.

[Explanation of symbols]

 1 Conductive Support 2 Charge Generation Layer (CGL) 3 Charge Transport Layer (CTL) 4 Photosensitive Layer 5 Intermediate Layer 6 Layer Containing Charge Transport Material 7 Charge Generation Material

Claims (6)

[Claims] 1. An electrophotographic photoreceptor having a photosensitive layer provided on a conductive support, wherein the photosensitive layer contains a compound represented by the following general formula [A]. Embedded image 2. The electrophotographic photosensitive member according to claim 1, wherein the compound represented by the general formula [A] is a compound represented by the following general formula [a]. Embedded image 3. An electrophotographic photoreceptor having a photosensitive layer provided on a conductive support, wherein the photosensitive layer contains a compound represented by the following general formula [B]. Embedded image 4. The electrophotographic photoreceptor according to claim 3, wherein the compound represented by the general formula [B] is a compound represented by the following general formula [b]. [Chemical 4] 5. An electrophotographic photoreceptor having a photosensitive layer provided on a conductive support, wherein the photosensitive layer contains a compound represented by the following general formula [C]. Embedded image 6. The electrophotographic photosensitive member according to claim 5, wherein the compound represented by the general formula [C] is a compound represented by the following general formula [c]. [Chemical 6]