JPH06194852A - Electrophotogaphic photoreceptor - Google Patents

Abstract

PURPOSE:To enhance photosensitive characteristics and strength against thermal and mechanical impacts and to enable low-cost production. CONSTITUTION:The electrophotographic photoreceptor is characterized by containing on a conductive substrate as an effective component at least one of compounds represented by formula in which each of R<1> and R<2> is H or optionally, substituted alkyl or aryl; and Rf is an aliphatic hydrocarbon group having fluorine atoms.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic photoreceptor, and more particularly to an electrophotographic photoreceptor having a photosensitive layer containing a specific compound.

[0002]

2. Description of the Related Art Conventionally, inorganic materials such as selenium, cadmium sulfide and zinc oxide have been used as photoconductive materials for photoconductors used in electrophotography.
The term "electrophotographic method" generally means that a photoconductive photoconductor is first charged in a dark place by, for example, corona discharge, and then imagewise exposed to selectively dissipate the charge only in the exposed portion. An electrostatic latent image is obtained, and this latent image portion is developed with electroscopic fine particles (toner) composed of a coloring material such as a dye or pigment and a binder such as a polymer substance to be visualized to form an image. This is one of the image forming methods.

The basic characteristics required for a photoconductor in such an electrophotographic method are: (1) being able to be charged to an appropriate potential in a dark place, (2) being small in dissipation of a charge in a dark place, (3) It is possible to rapidly dissipate the charge by light irradiation.

By the way, in reality, each of the above-mentioned inorganic substances has various advantages and, at the same time, has various drawbacks. For example, selenium, which is widely used at present, sufficiently satisfies the above conditions (1) to (3), but the manufacturing conditions are difficult, the manufacturing cost is high, the selenium is not flexible, and it is processed into a belt shape. It is difficult to handle, and it is sensitive to heat and mechanical shocks, so it requires careful handling. Cadmium sulfide and zinc oxide are used as photoconductors by dispersing them in a resin as a binder, but since they have mechanical defects such as smoothness, hardness, tensile strength and abrasion resistance, they can be repeated as they are. Can not be used.

In recent years, electrophotographic photoconductors using various organic substances have been proposed and some have been put to practical use in order to eliminate the drawbacks of these inorganic substances. For example, a photoreceptor comprising poly-N-vinylcarbazole and 2,4,7-trinitrofluoren-9-one (U.S. Pat. No. 34,34).
84237), a photoconductor obtained by sensitizing poly-N-vinylcarbazole with a pyrylium salt dye (described in JP-B-48-25658), and a photoconductor containing an organic pigment as a main component (special JP-A-47-37543), a photoreceptor containing a eutectic complex composed of a dye and a resin as a main component (described in JP-A-47-10735), and a triphenylamine compound dye-sensitized. (US Pat. No. 3,180,730), a photoreceptor using an amine derivative as a charge transport material (JP-A-57-195254), poly-N-vinylcarbazole and an amine derivative as a charge transport material. Photoreceptor used (JP-A-58-11)
55), a photoconductor using a benzidine compound among polyfunctional tertiary amine compounds as a photoconductive material (U.S. Pat. No. 3,265,496, JP-B-39-11546, JP-A-53-27033). ) And so on. These photoconductors have excellent properties and are considered to be of high value practically.However, in consideration of various demands on the photoconductor in the electrophotographic method, these demands are still insufficient. It is the actual situation that nothing satisfying the above is obtained. In particular, in recent years, many organic photoconductors have been put into practical use, and studies on improvement of their durability have been actively made. One of them is to improve the mechanical durability against abrasion and scratches, and also to add releasing property and water repellent property, and to disperse a fluorine compound as a lubricant on the surface of the photoconductor to prevent toner fusion. Is effective and various proposals have been made (Japanese Patent Laid-Open No. 63-56658,
JP-A-63-61255, JP-A-61-6125
6, JP-A-63-113460, JP-A-1
-307761 and JP-A-2-189551). However, even though the above-mentioned fluorine-based compound is a surface modifier, it cannot be denied that it adversely affects the electrophotographic characteristics, especially the sensitivity.

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to solve the various drawbacks of the above-described conventional photoconductor and to provide a photoconductor which can sufficiently satisfy the conditions required in the electrophotographic method. Especially. Another object of the present invention is to provide an electrophotographic photosensitive member which is easy to manufacture, relatively inexpensive, and excellent in durability.

[0007]

According to the present invention, a conductive layer is provided with a photosensitive layer containing at least one stilbene compound represented by the following general formula [Chem. 1] as an active ingredient. A photoconductor for electrophotography is provided.

[Chemical 1] (R ¹ and R ² represent a hydrogen atom, a substituted or unsubstituted alkyl group or an aryl group, and Rf represents an aliphatic hydrocarbon group having a fluorine atom.)

In the present invention, the stilbene compound represented by the general formula (I) (Formula 1) contained in the photosensitive layer is
When R ¹ and R ² are the same, for example, the following general formula (I
I) (Chemical 2)

[Chemical 2] (In the formula, Rf represents an aliphatic hydrocarbon group having a fluorine atom) and an aminostilbene compound represented by the general formula (III)

Embedded image produced by reacting with a halogen compound represented by R ¹ -X (III) (wherein, X represents a halogen atom, and R ¹ represents a substituted or unsubstituted alkyl group or aryl group) . Also, R
^{When 1} and R ² are different, it is produced by reacting stepwise with an amino group having a protecting group.

In the above general formula (I) [Formula 1], when R ¹ or R ² is an aryl group, specific examples thereof include a non-condensed carbon-hydrogen group such as a phenyl group, a biphenyl group and a terphenylyl group or a condensed polycyclic Hydrocarbon groups are mentioned.

In this case, the condensed polycyclic hydrocarbon group preferably has 18 or less carbon atoms forming a ring, for example, pentalenyl group, indenyl group, naphthyl group,
Azulenyl group, heptanenyl group, biphenylenyl group, a
s-indacenyl group, fluorenyl group, S-indacenyl group, acenaphthylenyl group, preadenyl group, acenaphthenyl group, phenalenyl group, phenanthryl group, anthryl group, fluoranthenyl group, acephenanthrylenyl group, aceanthrylenyl group, triphenylenyl group Group, pyrenyl group, chrysenyl group, naphthacenyl group and the like.

When R ¹ or R ² is an aryl group, it also includes those having the following substituents.

(1) Halogen atom, cyano group, nitro group (2) Alkyl group, preferably C _{1 to} C _{12 and} especially C ₁
To C ₈ and more preferably C _{1 to} C ₄ linear or branched alkyl groups, and these alkyl groups further include a fluorine atom, a hydroxyl group, a cyano group, a C _{1 to} C ₄ alkoxy group, a phenyl group or A phenyl group substituted with a halogen atom, a C ₁ -C ₄ alkyl group or a C ₁ -C ₄ alkoxy group may be contained. Specifically, a methyl group, an ethyl group,
n-propyl group, i-propyl group, t-butyl group, s-
Butyl group, n-butyl group, i-butyl group, trifluoromethyl group, 2-hydroxyethyl group, 2-cyanoethyl group, 2-ethoxyethyl group, 2-methoxyethyl group, benzyl group, 4-chlorobenzyl group, 4-methylbenzyl group, 4-methoxybenzyl group, 4-phenylbenzyl group and the like can be mentioned.

(3) Alkoxy group (-OR ₁ ); R ₁ represents the alkyl group defined in (2). Specifically, methoxy group, ethoxy group, n-propoxy group, i-propoxy group, t-butoxy group, n-butoxy group, s-butoxy group, i-butoxy group, 2-hydroxyethoxy group, 2
-Cyanoethoxy group, benzyloxy group, 4-methylbenzyloxy group, trifluoromethoxy group and the like can be mentioned.

(4) Aryloxy group: Examples of the aryl group include a phenyl group and a naphthyl group. This is C ₁
Alkoxy group -C _4, alkyl group, or a halogen atom C ₁ -C ₄ may contain a substituent group. Specifically, phenoxy group, 1-naphthyloxy group, 2-naphthyloxy group, 4-methylphenoxy group, 4-methoxyphenoquino group, 4-chlorophenoxy group, 6-methyl-2.
-A naphthyloxy group etc. are mentioned.

(5) Alkyl mercapto group (--S
R ₁ ); R ₁ represents an alkyl group defined in (2). Specific examples include a methylthio group, an ethylthio group, a phenylthio group, a p-methylphenylthio group and the like.

[0016] Represents an alkyl group or an aryl group, and
Are, for example, phenyl group, biphenylyl group or naphthyl group.
Group, which is C₁~ C_FourAlkoxy group of C
₁~ C_FourAlkyl group or halogen atom as a substituent
May be included. R₂And R₃May jointly form a ring
Yes. Also, forming a ring in cooperation with the carbon atom on the aryl group
Good. ) Specifically, an amino group, a diethylamino group,
N-methyl-N-phenylamino group, N, N-dipheny
Ruamino group, N, N-di (p-tolyl) amino group, diamino
Benzylamino group, piperidino group, morpholino group, Juro
Examples thereof include a lysyl group.

(7) Methylenedioxy group, alkylenedioxy group such as methylenedithio group, alkylenedithio group, and the like.

Specific examples of the stilbene compound according to the present invention will be shown below.

[Table 1- (1)]

[Table 1- (2)]

[Table 1- (3)]

The photoreceptor of the present invention comprises a photosensitive layer 2 (2 ', 2') containing one or more of the above-mentioned stilbene compounds.
′, 2 ′ ″ ′ or 2 ′ ″ ′ ″), but depending on the application of these stilbene compounds, they are used as shown in FIG. 1, FIG. 2, FIG. 3, FIG. 4 or FIG. be able to.

The photoconductor in FIG. 1 has a conductive support 1 on which a stilbene compound, a sensitizing dye and a binder (binder resin) are provided.
A photosensitive layer 2 made of is provided. The stilbene compound here acts as a photoconductive substance, and the generation and transfer of charge carriers required for light attenuation are performed via the stilbene compound. However, since the stilbene compound has almost no absorption in the visible region of light, it is necessary to add a sensitizing dye having absorption in the visible region for sensitization for the purpose of forming an image with visible light. .

The photoreceptor shown in FIG. 2 is provided with a photosensitive layer 2'wherein a charge generating substance 3 is dispersed in a charge carrier medium 4 composed of a stilbene compound and a binder on a conductive support 1. is there. The stilbene compound here forms a charge carrier medium together with the binder (or binder and plasticizer), while the charge generating substance 3 (charge generating substance such as an inorganic or organic pigment) generates charge carriers. In this case, the charge carrier medium 4 is mainly responsible for receiving the charge carriers generated by the charge generating substance 3 and carrying them. In this photoreceptor, the basic condition is that the charge generating substance and the stilbene compound do not overlap each other mainly in the visible wavelength region. This is because it is necessary to transmit light to the surface of the charge generating substance 3 in order to efficiently generate charge carriers in the charge generating substance 3. The stilbene compound represented by the general formula (I) has almost no absorption in the visible region and generally absorbs light in the visible region to generate charge carriers.
Its feature is that it works particularly effectively as a charge carrier when combined with.

The photoconductor in FIG. 3 is a photoconductive layer 2 ″ composed of a laminate of a charge generation layer 5 having a charge generation substance 3 as a main component and a charge transport layer 4 containing a stilbene compound on a conductive support 1. Is provided. With this photoreceptor,
The light transmitted through the charge transport layer 4 reaches the charge generation layer 5, and charge carriers are generated in that region, while the charge transport layer 4 is generated.
Receives the injection of charge carriers and carries them. The charge carriers necessary for light attenuation are generated by the charge generating substance 3, and the charge carriers are carried by the charge carrier layer 4 (mainly stilbene compound is used). Work). Such a mechanism is the same as that explained for the photoconductor shown in FIG.

The photoreceptor in FIG. 4 has a third charge generation layer 5
The stacking order of the charge transport layer 4 containing the stilbene compound is reversed, and the mechanism of generation and transport of the charge carriers can be the same as described above. In this case, considering the mechanical strength, the protective layer 6 may be provided on the charge generation layer 5 as in the fifth case.

In order to actually produce the photoreceptor of the present invention, the process shown in FIG.
In the case of the photoreceptor shown in 1 above, one or more stilbene compounds are dissolved in a solution in which a binder is dissolved, and then a sensitizing dye is added to the solution to prepare a solution on the conductive support 1. Then, the photosensitive layer 2 may be formed by applying it to the substrate and drying it.

The thickness of the photosensitive layer is 3 to 50 μm, preferably 5 to 20 μm. The amount of the stilbene compound in the photosensitive layer 2 is 30 to 70% by weight, preferably about 50% by weight, and the amount of the sensitizing dye in the photosensitive layer 2 is 0.1 to 5% by weight, preferably 0. It is 5 to 3% by weight. As sensitizing dyes, triarylmethane dyes such as Brilliant Green, Victoria Blue B, Methyl Violet, Crystal Violet, Acid Violet 6B, Rhodamine B, Rhodamine 6G, Rhodamine G Extra, Eosin S, Erythrosine, Rose Bengal, Fluorescein are available. Such as xanthene dye, thiazine dye such as methylene blue, cyanine dye such as cyanine, 2,6-diphenyl-4- (N, N-dimethylaminophenyl) thiapyrylium perchlorate, benzopyrylium salt (Japanese Patent Publication No. No. 25658 gazette) and the like. In addition, these sensitizing charges may be used alone or in combination of two or more kinds.

Further, in order to manufacture the photoreceptor shown in FIG. 2, fine particles of the charge generating substance 3 are dispersed in a solution in which one or more kinds of stilbene compounds and a binder are dissolved,
This may be coated on the conductive support 1 and dried to form the photosensitive layer 2 '.

The thickness of the photosensitive layer 2'is 3 to 50 μm, preferably 5 to 20 μm. The amount of the stilbene compound in the photosensitive layer 2'is 10 to 95% by weight, preferably 3
0 to 90% by weight, and the amount of the charge generating substance 3 in the photosensitive layer 2'is 0.1 to 50% by weight, preferably 1 to
It is 20% by weight. Examples of the charge generating substance 3 include inorganic pigments such as selenium, selenium-tellurium, cadmium sulfide, cadmium sulfide-selenium, and α-silicon, and examples of organic pigments include CI Pigment Blue 25 (color index CI 21180) and CI Pigment Red 41. (CI21200), CI Acid Red 52 (CI 45100), CI Basic Red 3 (CI45210), an azo pigment having a carbazole skeleton (described in JP-A-53-95033), an azo pigment having a distyrylbenzene skeleton (special Kaisho 53-13
3445), azo pigments having a triphenylamine skeleton (described in JP-A-53-132347), and azo pigments having a dibenzothiophene skeleton (JP-A-54-54).
No. 21728), an azo pigment having an oxadiazole skeleton (described in JP-A-54-12742), and an azo pigment having a fluorenone skeleton (JP-A-54).
No. 22834), an azo pigment having a bisstilbene skeleton (described in JP-A-54-17733), an azo pigment having a distyryl oxadiazole skeleton (described in JP-A-54-2129). , An azo pigment having a distyrylcarbazole skeleton (JP-A-54-14)
967), for example, phthalocyanine-based pigments such as CI Pigment Blue 16 (CI 74100), for example, CIVAT BROWN 5
(CI73410), CI Bat Die (CI 73
030) and other indigo pigments, Argoscarlet B
(Produced by Bayer Co., Ltd.), indanthren scarlet R (produced by Bayer Co., Ltd.) and the like.
These charge-generating substances may be used alone or in combination of two or more.

Further, in order to manufacture the photoreceptor shown in FIG. 3, the charge generating substance is vacuum-deposited on the conductive support 1 or more, or the fine particles 3 of the charge generating substance are appropriately dissolved in a binder. The charge generation layer 5 is prepared by applying a dispersion liquid dispersed in a different solvent and drying it, and further, if necessary, surface finishing and film thickness adjustment by a method such as buffing.
Is formed, and a solution in which one or more kinds of stilbene compounds and a binder are dissolved is applied thereon and dried to form the charge transport layer 4. The charge generating material used for forming the charge generating layer 5 is the same as that used in the description of the photosensitive layer 2 '.

The charge generation layer 5 has a thickness of 5 μm or less, preferably 2 μm or less, and the charge transport layer 4 has a thickness of 3 to 50.
μm, preferably 5 to 20 μm is suitable. When the charge generation layer 5 is of a type in which the fine particles 3 of the charge generation layer substance are dispersed in a binder, the proportion of the fine particles 3 of the charge generation substance in the charge generation layer 5 is 10 to 95% by weight, preferably Is about 50 to 90% by weight. In addition, the charge transport layer 4
The amount of the compound in 10 to 95% by weight, preferably 3
It is 0 to 90% by weight. To prepare the photoreceptor shown in FIG. 4, a solution in which a stilbene compound and a binder are dissolved is applied on the conductive support 1 and dried to form the charge transport layer 4, and then the charge transport layer is formed. The charge generation layer 5 may be formed by applying fine particles of the charge generation layer substance on top of the above, and optionally dispersing a dispersion liquid in a solvent in which a binder is dissolved by a method such as spray coating. The amount ratio of the charge generation layer or the charge transport layer is the same as that described in FIG. The photoconductor shown in FIG. 5 can be prepared by forming a protective layer 6 on the charge generation layer 5 of the photoconductor thus obtained by further spraying an appropriate resin solution by a method such as spray coating. As the resin used here, the binder described below can be used.

In the production of any of these photoreceptors, a metal plate or metal foil such as aluminum, a plastic film deposited with a metal such as aluminum, or a paper subjected to a conductive treatment is used as the conductive support 1. To be Further, as the binder, condensation resins such as polyamide, polyurethane, polyester, epoxy resin, polyketone, and polycarbonate, and vinyl polymers such as polyvinyl ketone, polystyrene, poly-N-vinylcarbazole, and polyacrylamide are used. All insulating and adhesive resins can be used. If necessary, a plasticizer is added to the binder, and examples of such a plasticizer include halogenated paraffin, polychlorinated biphenyl, dimethylnaphthalene, dibutyl phthalate and the like.

Further, the photoreceptor obtained as described above may be provided with an adhesive layer or a barrier layer between the conductive support and the photosensitive layer, if necessary. Materials used for these layers include polyamide, nitrocellulose,
Aluminum oxide or the like is preferable, and the film thickness is preferably 1 μm or less. To make a copy using the photoreceptor of the present invention,
After the photosensitive surface is charged and exposed, it is developed and, if necessary, transferred to paper or the like. The photoconductor of the present invention has excellent advantages such as high sensitivity and high flexibility.

[0032]

EXAMPLES The present invention will be described below with reference to examples. In the following examples, all parts are parts by weight.

[Synthesis of Compound of General Formula (I)] [Compound No. Synthesis Example 8] 4- (2,2,2-trifluoroethoxy) -4'-aminostilbene 1.20
g, P-iodotoluene 3.57 g, potassium carbonate 2.
27 g and 0.10 g of copper powder were taken in 20 ml of nitrobenzene, and the mixture was stirred under reflux for 6 hours under azeotropic dehydration under a nitrogen stream. After cooling to room temperature, the insoluble portion was removed by filtration, nitrobenzene was distilled off under reduced pressure, and the residue was dissolved in toluene. This solution was washed with water and dried over magnesium sulfate, and then toluene was distilled off under reduced pressure to obtain a brown oily substance. This is subjected to column treatment [carrier: silica gel eluent; toluene / n-hexane =
2/5 (vol.)], And then recrystallized from a mixed solvent of toluene-ethanol to give 4- (2) of pale yellow needle crystals.
1.10 g of 2,2-trifluoroethoxy) -4'-bis (4-methylphenyl) aminostilbene was obtained. Melting point: 125.5-126.5 ° C. Elemental analysis value (%) C H N actual value 76.06 5.45 2.74 C ₃₀ H ₂₆ NOF ₃ 76.08 5.55 2.96 Calculated value ) Infrared absorption spectrum (KBr tablet method)

[Table 2] Other stilbene compounds were synthesized in the same manner as above.

Example 1 In a ball mill, 76 parts of Diane Blue (CI Pigment Blue 25, CI21180) as a charge generating substance, 1260 parts of a 2% tetrahydrofuran solution of a polyester resin (Vylon 200, manufactured by Toyobo Co., Ltd.) and 3700 parts of tetrahydrofuran were placed in a ball mill. The obtained dispersion liquid was pulverized and mixed with a doctor blade to form a charge generating layer having a thickness of about 1 μm on the aluminum surface of a conductive aluminum-deposited polyester base, which was then dried. . On the other hand, as the charge carrier substance, compound specific example No. 2 parts of the stilbene compound of No. 8, 2 parts of a polycarbonate resin (Panlite K1300, manufactured by Teijin Limited) and 16 parts of tetrahydrofuran were mixed and dissolved to form a solution, which was then applied onto the charge generation layer using a doctor blade. Then, it is dried at 80 ° C. for 2 minutes and then at 120 ° C. for 5 minutes to form a charge carrying layer having a thickness of about 20 μm. Created 1.

Examples 2 to 14 Charge-generating substance and charge-carrying substance (stilbene compound)
In the same manner as in Example 1 except that the ones shown in Table 2 were replaced. 2-22 were created.

[Table 3- (1)]

[Table 3- (2)]

[Table 3- (3)]

[Table 3- (4)]

Example 29 Selenium was vacuum-deposited to a thickness of about 1 μm on an aluminum plate having a thickness of about 300 μm to form a charge generation layer. Then No. 2 parts of stilbene compound of 8 and polyester resin (Polyester Adhesive 49000 manufactured by DuPont)
3 parts and 45 parts of tetrahydrofuran were mixed and dissolved to prepare a charge transport layer forming liquid, which was applied onto the above charge generation layer (selenium vapor deposition layer) using a doctor blade and naturally dried, and then under reduced pressure. Dry thickness about 10 μm
The charge transport layer of No. 1 is formed, and the photoconductor No. Two
Got 9.

Example 30 Perylene pigment instead of selenium

[Chemical 4] Was used to form a charge generation layer (thickness: about 0.6 μm), and the stilbene compound N was used as a charge carrier.
o. In the same manner as in Example 29 except that the photoconductor No. 8 was used. 30 was created.

Example 31 A mixture of 1 part of Diane Blue (the same as that used in Example 1) and 158 parts of tetrahydrofuran was ground in a ball mill and mixed. 12 parts of the stilbene compound of No. 8 and 18 parts of polyester resin (Polyester Adhesive 49000 manufactured by DuPont) were further mixed and the resulting photosensitive layer forming liquid was applied onto an aluminum vapor-deposited polyester film using a doctor blade. And dried at 100 ° C. for 30 minutes to form a photosensitive layer having a thickness of about 16 μm. 31 was created.

Example 32 On a polyester film substrate vapor-deposited on aluminum,
The charge transport layer coating liquid used in Example 1 was blade coated in the same manner as in Example 1, and then dried to form a charge transport layer having a thickness of about 20 μm. Bisazo pigment (P-2) 13.
5 parts, polyvinyl butyral (trade name: XYHL Union Carbide Plastic Co., Ltd.) 5.4 parts, THF 6
After 80 parts and 1020 parts of ethyl cellosolve were pulverized and mixed in a ball mill, 1700 parts of ethyl cellosolve were added and mixed by stirring to obtain a charge generation layer coating liquid. This coating solution is spray-coated on the above charge transport layer, and the coating is carried out at 100 ° C. for 1 hour.
It was dried for 0 minutes to form a charge generation layer having a thickness of about 0.2 μm. Further, a methanol / n-butanol solution of a polyamide resin (trade name: CM-8000, manufactured by Toray) is spray-coated on the charge generation layer and dried at 120 ° C. for 30 minutes to form a protective layer having a thickness of about 0.5 μm. To form photoconductor N
o. 32 was created.

Photoreceptor No. 1 thus prepared 1-32
For the above, using a commercially available electrostatic copying paper tester (type SP428 manufactured by KK Kawaguchi Denki Seisakusho), a corona discharge of -6KV or + 6KV was performed for 20 seconds to charge the sample, and then the sheet was left in a dark place for 20 seconds, and the surface at that time was measured. The potential Vpo (volt) is measured, and then the tungsten lamp light is irradiated so that the illuminance on the surface of the photoconductor becomes 4.5 lux, and the time (second) until the surface potential becomes 1/2 of Vpo is obtained. , Exposure amount E
½ (lux · sec) was calculated. The results are shown in Table 3.

After charging each of the above photoconductors using a commercially available electrophotographic copying machine, light irradiation was performed through the original drawing to form an electrostatic latent image, which was developed with a dry developer. When the obtained image (toner image) was electrostatically transferred onto plain paper and fixed, a clear transferred image was obtained. Even when a wet type developer was used as the developer, a clear transfer image was similarly obtained.

[Table 4- (1)]

[Table 4- (2)]

[Table 4- (3)]

[0042]

The photoconductor of the present invention is excellent not only in its photosensitivity but also in its strength against heat and mechanical shock, and can be manufactured at low cost.

[Brief description of drawings]

FIG. 1 is an enlarged cross-sectional view of an electrophotographic photosensitive member according to the present invention in a thickness direction.

FIG. 2 is a cross-sectional view in which the electrophotographic photosensitive member according to the present invention is enlarged in the thickness direction.

FIG. 3 is a cross-sectional view in which the electrophotographic photosensitive member according to the present invention is enlarged in the thickness direction.

FIG. 4 is a cross-sectional view in which the electrophotographic photosensitive member according to the present invention is enlarged in the thickness direction.

FIG. 5 is a cross-sectional view in which the electrophotographic photosensitive member according to the present invention is enlarged in the thickness direction.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Conductive support 2, 2 ', 2 ", 2"' ", 2 '"' ... Photosensitive layer 3 ... Charge generating substance 4 ... Charge carrying medium or charge carrying layer 5 ... Charge generating layer 6 ... Protection layer

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hiroshi Adachi 1-3-6 Nakamagome, Ota-ku, Tokyo Stock company Ricoh (72) Inventor Chiaki Tanaka 1-3-3 Nakamagome, Tokyo Company Ricoh

Claims (2)

[Claims] 1. A photoconductor for electrophotography, which comprises a photosensitive layer containing, as an active ingredient, at least one stilbene compound represented by the following general formula [Chemical Formula 1] on a conductive support. [Chemical 1] (R ¹ and R ² represent a hydrogen atom, a substituted or unsubstituted alkyl group or an aryl group, and Rf represents an aliphatic hydrocarbon group having a fluorine atom.) 2. The electrophotographic photoreceptor according to claim 1, wherein the photosensitive layer is a laminated type of a charge generation layer and a charge transport layer.