JP2002214810A - Electrophotographic photoreceptor, coating solution for charge transport layer, and method for producing electrophotographic photoreceptor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrophotographic photoreceptor, having low friction between it and each member of a device, superior durability and superior electrical characteristics, and to provide a coating liquid for producing the photoreceptor. SOLUTION: In the electrophotographic photoreceptor, obtained by successively stacking an electric charge generating layer and an electric charge transport layer on an electrically conductive substrate, condensed polycyclic compound particles having a molecular weight of 150-1,000 are contained in the electric charge transport layer.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an electrophotographic photosensitive member and a coating solution for a charge transport layer. More specifically, an organic electrophotographic photoreceptor having a charge generation layer and a charge transport layer laminated thereon,
The present invention relates to a charge transport layer coating solution used for forming the charge transport layer.

[0002]

2. Description of the Related Art In recent years, organic photoreceptors using non-polluting organic substances have been actively developed and widely used. Above all, so-called function-separated type photoconductors in which a carrier generation function and a carrier transport function are shared by different substances and a compound having desired characteristics can be selected from a wide range have been actively developed. However, such organic photoconductors generally have lower mechanical strength than conventional inorganic photoconductors,
There are problems such as abrasion and abrasion due to mechanical external forces such as a cleaning blade and a developing brush.

For example, in a conventional photoreceptor in which a carrier generation layer and a carrier transport layer are sequentially laminated on a support, the carrier transport layer binds a low-molecular carrier transport material with an inert polymer resin binder. Since the carrier transport layer is formed, the carrier transport layer is generally soft, and it is not always sufficient to achieve both mechanical properties and electrophotographic properties. In the case of a composition having a high sensitivity or a certain kind of resin binder, the surface of the photoreceptor is scratched or worn due to rubbing of a cleaning blade or the like when the photoreceptor is repeatedly used. Further, with a composition having a high abrasion resistance or a certain kind of resin binder, the sensitivity was low or the electrophotographic properties such as an increase in residual potential could not be satisfied.

Regarding these problems, a silicone-containing resin is used in the carrier transport layer as an agent for reducing the coefficient of friction of the surface of the photoreceptor, reducing the surface energy, and reducing the wear (Japanese Patent Application Laid-Open No. 61-1986).
Nos. 219049 and 62-205357, and fluorine-containing resins (Japanese Patent Laid-Open Nos. 50-23231, 61-116362, and 61-20463).
No. 3, No. 61-270768), and a method using addition of silica as inorganic fine particles has been proposed. However, the electrophotographic properties such as low sensitivity, the increase in residual potential due to repeated use, and the mechanical durability such as a decrease in image quality due to wear and scratches and a decrease in sensitivity due to film wear are still insufficient. I couldn't.

In addition, when inorganic fine particles such as silica are added, since the density of the particles themselves is larger than that of the organic substance, defects in liquid stability such as particles settling when the coating liquid is left unattended, and characteristics of the fine particles. However, there is a problem that the liquid viscosity is significantly increased due to the thixotropic property, and the productivity is reduced.

[0006]

SUMMARY OF THE INVENTION The present invention is a photosensitive composition having high sensitivity, excellent abrasion resistance, excellent printing durability, high durability, and lacking in potential stability due to repeated use, an increase in residual potential and a decrease in light sensitivity. Is to provide the body. Another object of the present invention is to provide a method for producing an electrophotographic photoreceptor having excellent productivity by producing a coating solution for a charge transport layer having excellent storage stability for producing an electrophotographic photoreceptor. It is in.

[0007]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies in view of the above-mentioned problems, and as a result, have been made of a specific condensed polycyclic compound as fine particles for improving the slip property in the charge transport layer. When particles are used, dispersibility is improved,
The inventors have found that an electrophotographic photoreceptor having excellent coating solution stability, abrasion resistance and excellent electrical properties can be obtained, and the present invention has been accomplished. That is, the gist of the present invention is that an electrophotographic photoreceptor obtained by sequentially laminating a charge generation layer and a charge transport layer on a conductive support mainly comprises a condensed polycyclic compound having a molecular weight of 150 to 1,000 in the charge transport layer. An electrophotographic photoreceptor characterized by containing particles as constituent components.

Another aspect of the present invention resides in a coating solution for a charge transport layer containing at least a charge transport material, a binder resin, and particles having the above-mentioned condensed polycyclic compound as a main component. Another aspect of the present invention is to provide a method for manufacturing an electrophotographic photoreceptor in which a charge generation layer and a charge transport layer are sequentially laminated on a conductive support. A method for producing an electrophotographic photoreceptor, wherein a charge transport layer is provided.

The electrophotographic photoreceptor of the present invention is obtained by sequentially laminating a charge generation layer and a charge transport layer on a conductive support. A blocking layer is provided between the conductive support and the charge generation layer, if necessary. The blocking layer may be an alumite layer or a resin-based undercoat layer (also referred to as an intermediate layer) or a combination of these. Is used. Further, an overcoat layer can be provided outside the photosensitive layer as necessary.

As the conductive support used in the present invention, for example, a support made of a metal such as aluminum, stainless steel, copper, nickel or the like, or a polyester film,
Aluminum, copper,
There is a device provided with a conductive layer made of palladium, tin oxide, indium oxide, or the like. Above all, a metal endless pipe cut into an appropriate length is desirable, and aluminum is most preferably used. The surface of the conductive support can be subjected to various treatments such as an oxidation treatment and a chemical treatment within a range that does not affect the image quality.

When the undercoat layer is provided on the conductive support, the binder resin may be polyvinyl methyl ether, poly-N-vinyl imidazole, polyethylene oxide, ethyl cellulose, methyl cellulose, ethylene-acrylic acid copolymer, polyamide , Casein, gelatin, polyethylene, polyester, phenolic resin, vinyl chloride-vinyl acetate copolymer, epoxy resin, polyvinylpyrrolidone, polyvinylpyridine, polyurethane,
Resin materials such as polyglutamic acid, polyacrylic acid, and polyamide resin can be used. Among them, a polyamide resin having excellent adhesion to a supporting substrate and low solubility in a solvent used for a charge generation layer coating solution is preferred.

The undercoating layer preferably contains metal oxide fine particles such as alumina and titania and an organic or inorganic dye capable of absorbing laser light, particularly for the purpose of preventing interference fringes during laser exposure. It is effective. The thickness of the undercoat layer is usually 0.1 to 10 μm, preferably 0.1 to 10 μm.
2 to 6 μm. The content ratio of the metal oxide fine particles or the pigment to the binder resin is not particularly limited, but it is preferable to use the metal oxide fine particles or the pigment in the range of 40 to 400 parts by weight with respect to 100 parts by weight of the binder when dispersing the undercoat layer. It is preferable in terms of storage stability of the liquid and applicability.

As the charge generating material used for the charge generating layer, any known materials can be used. Selenium and its alloys, arsenic-selenium, cadmium sulfide, zinc oxide, other inorganic photoconductive materials, phthalocyanine, Azo dye, quinacridone, polycyclic quinone, pyrylium salt, indigo, thioindigo, anthantrone, pyranthrone,
Various organic pigments and dyes such as cyanine can be used. Among them, metal-free phthalocyanine, copper, indium chloride, gallium chloride, tin, oxytitanium, zinc, metals such as vanadium, or oxides, chloride-coordinated phthalocyanines,
Azo pigments such as monoazo, bisazo, trisazo, and polyazos are preferred. Of these, oxytitanium phthalocyanine is more preferable from the viewpoint of sensitivity when used in an image forming apparatus equipped with an exposure device using a laser beam in the range of 550 to 850 nm, and particularly, the Bragg angle (2θ) in X-ray diffraction using CuKα radiation. ± 0.2 °) = 27.3
Most preferred is Y-type oxytitanium phthalocyanine having a characteristic peak at °.

The charge generation layer can be obtained by coating and drying a coating solution obtained by dissolving or dispersing fine particles of these substances and a binder polymer in a solvent. Examples of the binder include polymers and copolymers of vinyl compounds such as styrene, vinyl acetate, vinyl chloride, acrylate, methacrylate, vinyl alcohol, and ethyl vinyl ether, polyvinyl acetal, polycarbonate, polyester, polyamide, polyurethane, and cellulose ether. Phenoxy resin, silicon resin, epoxy resin and the like.

The ratio between the charge generating substance and the binder polymer is not particularly limited, but is generally 5 to 500 parts by weight, preferably 20 to 30 parts by weight, per 100 parts by weight of the charge generating substance.
0 parts by weight of binder polymer are used. Further, the charge generation layer may be a deposited film of the above-described charge generation substance. The thickness of the charge generation layer is 0.05 to 5 μm, preferably 0.1 to 5 μm.
２2 μm.

The charge transport layer is formed on the charge generation layer by a known polymer having excellent performance as a binder;
A charge transport material and particles having a condensed polycyclic compound described below as a main component (hereinafter sometimes referred to as condensed polycyclic compound particles) are mixed, dissolved or dispersed in an appropriate solvent, and It can be produced by applying a coating solution obtained by adding an electron-accepting compound or a plasticizer, inorganic fine particles or other additives according to the above. The thickness of the charge transport layer is usually in the range of 10 to 50 μm, preferably 13 to 35 μm.

The electrophotographic photoreceptor of the present invention is characterized in that the charge transport layer contains particles containing a condensed polycyclic compound having a molecular weight of 150 to 1,000 as a main component. In the present invention, the condensed polycyclic compound is a compound having a structure in which two or more aromatic rings or aliphatic rings are condensed in a molecule. The phrase "condensed polycyclic compound as a main component" refers to the main component of the particles, specifically, usually 80% by weight or more, preferably 90% by weight or more,
More preferably, 95% by weight or more is a condensed polycyclic compound, which may contain a small amount of various additives for various purposes such as increasing the dispersion stability of the particles and controlling the particle size. It is. Unlike the inorganic particles and the resin particles, such fused polycyclic compound particles are mainly formed by the intermolecular force between the molecules. Then, it is presumed that the condensed polycyclic compound has portions of the polycyclic structure overlapping each other in layers. In such a structure, since the intermolecular force is relatively small, when an external force is applied, it is possible for a part of the layer maintained by the intermolecular force to shift or be scraped off. Therefore, it is possible to avoid that the particle itself is removed and a hole is formed in that portion.

The condensed polycyclic compound used in the present invention may have a condensed ring structure of two or more rings.
A compound having a 6-ring fused ring structure, more preferably a compound having a 3-ring or 4-ring fused ring structure. More specifically, a compound represented by the following general formula (I) is suitably used.

[0019]

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(In the formula (I), Y represents a sulfur atom, an oxygen atom or —NR ¹⁷ , and R ¹⁷ represents an alkyl group which may have a substituent or an aryl which may have a substituent. Group,
Or an aralkyl group which may have a substituent.
R ^{11 to} R ¹⁶ each independently represent an alkyl group, an alkenyl group,
Represents an aryl group, an aralkyl group, a carboxyl group, an alkoxycarbonyl group, a hydroxyalkyl group, an aminoalkyl group, an aminocarbonyl group, an N-alkylaminocarbonyl group, or an N-arylaminocarbonyl group. Further, R ^{11 to} R ¹⁶ may bond or condense with each other to form a cyclic structure. )

In the formula (I), Y represents an oxygen atom, a sulfur atom or —NR ¹⁷ , of which an oxygen atom or
The case where NR ¹⁷ is R ¹⁷ is an optionally substituted aryl group is preferred. When R ¹⁷ is an aryl group, the substituent is preferably a chlorine atom, a fluorine atom, a nitro group, or a cyano group. R ^{11 to} R ¹⁶ are each independently an alkyl group,
An alkenyl group, an aryl group, an aralkyl group, a carboxyl group, an alkoxycarbonyl group, a hydroxyalkyl group, an aminoalkyl group, an aminocarbonyl group, an N-alkylaminocarbonyl group, and an N-arylaminocarbonyl group are represented by methyl. Groups or phenyl groups are preferred. R ^{11 to} R ¹⁶ may be bonded or condensed to each other to form a cyclic structure, but the cyclic structure is preferably a benzene ring, an acid anhydride, or an imide structure. Then, from the viewpoint that the molecules of the condensed polycyclic compound take a laminated structure to easily form particles, a compound having a high symmetry, specifically, a C2 space group or a Cs space group, or more symmetry is used. Is preferred.
Preferred specific examples of the condensed polycyclic compound used in the present invention are described below.

[0022]

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The molecular weight of the condensed polycyclic compound used in the present invention is from 150 to 1,000.
Since the melting point of the compound is low and the volatility and sublimability are high, handling is difficult. Further, when the molecular weight is 100
When it is larger than 0, it is generally easy to color, which causes inconvenience and makes the production difficult. The molecular weight of the condensed polycyclic compound is preferably 170 or more, more preferably 190 or more. Further, it is preferably 800 or less, more preferably 500 or less.

In the present invention, since the fused polycyclic compound particles are used in a state of being dispersed in the binder resin of the charge transport layer, it is necessary that the solubility in the binder resin and the coating solvent be as small as practical. Next, the condensed polycyclic compound particles of the present invention, after synthesizing the condensed polycyclic compound by a conventional method, pulverized by a ball mill, a co-ball mill, a sand grind mill, a pearl mill, a paint shaker, etc. It is manufactured so as to have a thickness of 0.1 to 10 μm, more preferably 0.3 to 1 μm. Depending on the type of the compound, the crystallinity is high and the releasability in the layered structure may be low. Therefore, a similar compound having different substituents can be co-synthesized for the purpose of appropriately reducing the crystallinity. In this case, the ratio of the compound used for the purpose of lowering the crystallinity to the main compound is preferably 0.01 to 5% by weight, more preferably 0.1 to 5% by weight.
３3% by weight. Alternatively, particles composed of different condensed polycyclic compounds may be prepared in advance, and these particles may be mixed and used.

The above-mentioned condensed polycyclic compound particles used in the present invention have better dispersibility in a coating solution and a binder resin than inorganic particles and the like, and no remarkable increase in viscosity due to thixotropic property is observed. It has excellent storage stability of coating liquid and excellent dispersibility even by dip coating, so that it can be applied uniformly. This not only improves productivity, but also reduces the wear after the production of the electrophotographic photosensitive drum. Alternatively, it is considered that an electrophotographic photoreceptor can be provided which improves mechanical properties such as slipperiness and also has excellent electric characteristics and image characteristics.

In the present invention, particles other than the fused polycyclic compound particles may be used in combination in order to improve the slipperiness of the charge transport layer. Examples of the particles used in combination include styrene-based, urethane-based, acrylic-based resin particles, and inorganic oxide fine particles. The condensed polycyclic compound particles and other particles contained in the charge transport layer are not preferred if they absorb light that should reach the charge generation layer during image exposure. When exposing by laser or LED, usually 550-10
Since the light has a wavelength of 00 nm, particles made of a material having no maximum absorption in the range of 550 to 1000 nm are preferably used. Further, if the addition of these particles does not affect various characteristics such as electric characteristics, image characteristics, and environmental characteristics, it is not limited to the charge transport layer alone, and the charge generation layer and the undercoat layer , Overcoat layers and intermediate layers.

As the charge transporting material in the charge transporting layer, a high molecular compound such as polyvinyl carbazole, polyvinyl pyrene, polyacenaphthylene, or a low molecular weight compound such as various pyrazoline derivatives, oxazole derivatives, hydrazone derivatives, stilbene derivatives, arylamine derivatives, etc. Molecular compounds can be used. Among them, compounds represented by the following general formula (II) are preferable in terms of sensitivity and other electrical characteristics. In particular,
The compound represented by the general formula (II) is preferable because the use of oxytitanium phthalocyanine as the charge generating substance significantly improves the electrical characteristics.

[0028]

Embedded image (In the general formula (II), Ar ¹ represents an optionally substituted benzene ring, an optionally substituted naphthalene ring, or an optionally substituted biphenyl ring;
r5 each independently represents an optionally substituted aromatic ring. )

In the general formula (II), Ar ¹ represents an optionally substituted benzene ring, an optionally substituted naphthalene ring, or an optionally substituted biphenyl ring. An optionally substituted biphenyl ring is preferred. As the substituent, a halogen atom, an alkyl group having 4 or less carbon atoms, an alkoxy group having 3 or less carbon atoms, an alkylthio group having 3 or less carbon atoms, a cyano group, and a nitro group are preferable. Atoms are more preferred. However, an unsubstituted aromatic ring is most preferred.

Ar ^{2 to} Ar ⁵ each independently represent an aromatic ring which may be substituted, and the aromatic ring may be any of an aromatic hydrocarbon and an aromatic heterocyclic ring. Is a benzene ring, a naphthalene ring, a phenanthrene ring,
Anthracene ring, pyridine ring, pyrrole ring, furan ring,
A thiophene ring, a benzofuran ring, a benzothiophene ring and the like. Of these, a benzene ring, a naphthalene ring and a thiophene ring are preferred.

The substituent on the aromatic ring may be a halogen atom, an alkyl group having 4 or less carbon atoms, an alkoxy group having 3 or less carbon atoms, an alkylthio group having 3 or less carbon atoms, a cyano group, a nitro group, or The following general formula (III)
The substituent represented by is preferred.

[0032]

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(In the general formula (III), Ar ⁶ represents a phenyl group which may be substituted with a halogen atom or an alkyl group. R ¹ and R ² each independently represent a hydrogen atom or a methyl group. n represents 1, 2 or 3.) In the general formula (III), Ar ⁶ represents a phenyl group which may be substituted with a halogen atom or an alkyl group, but is preferably an unsubstituted phenyl group. R ¹ and R ² represent a hydrogen atom or a methyl group, and a hydrogen atom is preferable. n represents 1, 2 or 3, but 2 is preferred. Further, among the charge transporting agent compounds represented by the general formula (I), compounds represented by the following general formula (IV) are particularly effective.

[0034]

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In the general formula (4), R ¹ , R ² , Ar ⁶ and n have the same meanings as described above. R ^{3 to} R ⁶ are each independently a hydrogen atom or a methyl group.

The binder used for the charge transport layer is preferably a polymer which has good compatibility with the above-mentioned charge transport material and does not crystallize or phase-separate the charge transport material after forming the coating film. Examples thereof include polymers and copolymers of vinyl compounds such as styrene, vinyl acetate, vinyl chloride, acrylate, methacrylate, vinyl alcohol, and ethyl vinyl ether, polyvinyl acetal, polycarbonate, polyester, polysulfone, and polyphenylene oxide. , Polyurethane, cellulose ester, cellulose ether, phenoxy resin, silicon resin, epoxy resin and the like. Also,
The binder used for the charge transport layer preferably has high strength and is at least partially compatible with the above-mentioned polysiloxane compound. In this respect, polycarbonate, polyarylate or a mixture thereof is preferably used.

The electron-accepting compound optionally contained in the charge transporting layer includes cyano compounds such as tetracyanoquinodimethane, dicyanoquinomethane, aromatic esters having a dicyanoquinovinyl group, 2,4,4 Metal complexes of nitro compounds such as 6-trinitrofluorenone, condensed polycyclic aromatic compounds such as perylene, diphenoquinone derivatives, quinones, aldehydes, ketones, esters, acid anhydrides, phthalides, substituted and unsubstituted salicylic acids , Substituted and unsubstituted metal salts of salicylic acid, metal complexes of aromatic carboxylic acids, and metal salts of aromatic carboxylic acids.

Preferably, cyano compounds, nitro compounds, condensed polycyclic aromatic compounds, diphenoquinone derivatives, metal complexes of substituted and unsubstituted salicylic acids, metal salts of substituted and unsubstituted salicylic acids, metal complexes of aromatic carboxylic acids, aromatic complexes It is preferred to use metal salts of carboxylic acids. Further, the photosensitive layer of the electrophotographic photoreceptor of the present invention may contain a well-known plasticizer, antioxidant, and ultraviolet absorber in order to improve film formability, flexibility, applicability, and mechanical strength. good

When an overcoat layer is further provided on the charge transport layer, examples of the binder resin include polyvinyl methyl ether, poly-N-vinyl imidazole, polyethylene oxide, ethyl cellulose, methyl cellulose, ethylene-acrylic acid copolymer, polyamide, Casein, gelatin, polyethylene, polyester, phenolic resin, vinyl chloride-vinyl acetate copolymer, epoxy resin, polyvinylpyrrolidone, polyvinylpyridine, polyurethane, polyglutamic acid, polyacrylic acid, polyamide resin, silicone resin, and fluorine resin are used. Preferably, polyurethane, silicone resin and fluorine resin are used. The thickness of the overcoat layer is usually 0.01 to 100 μm, preferably 1 to 10 μm.

[0040]

EXAMPLES The present invention will be described in more detail with reference to the following Examples, which should not be construed as limiting the scope of the present invention. Example 1 [Preparation of charge generation layer] To 10 parts of β-type oxytitanium phthalocyanine and 5 parts of polyvinyl butyral (trade name # 6000-C, manufactured by Denki Kagaku Kogyo Co., Ltd.), 500 parts of 1,2-dimethoxyethane were added. Pulverization and dispersion treatment were performed with a sand grind mill. This dispersion was prepared by depositing aluminum on a polyester film having a thickness of 75 μm and used as a conductive support, and the weight after drying was 0.4 g / m 2.
(Approximately 0.4 .mu.m) by a wire bar and dried to form a charge generation layer.

[Preparation of Charge Transporting Layer] 60 parts of a charge transporting agent (compound of the following A), 8 parts of a phenol compound (compound of the following B) as an antioxidant, a cyano-based compound (compound of the following C), polycarbonate resin 100 And a mixed solvent of tetrahydrofuran and toluene. To this, 1,4,5,8-naphthalenecarboxylic dianhydride (NTCDA) is added so that the weight ratio of polycarbonate resin / NTCDA becomes 100/3, and finally the solid content concentration becomes 20% by weight. The solution was adjusted as follows. This coating solution was applied on the above-mentioned charge generation layer with an applicator, dried at room temperature for 20 minutes, and further dried at 125 ° C. for 20 minutes to provide a charge transport layer so that the dry film pressure became 25 μm. . The electrophotographic photosensitive member thus obtained is designated as P1.

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Example 2 An electrophotographic photosensitive member was produced in the same manner as in Example 1 except that NTCDA was added so that the weight ratio of polycarbonate resin / NTCDA became 100/5.
The electrophotographic photosensitive member thus obtained is designated as P2. Example 3 An electrophotograph was prepared in the same manner as in Example 1, except that 1,8-naphthalic anhydride (NAD) was added in place of NTCDA so that the weight ratio of polycarbonate resin / NAD was 100/3. A photoreceptor was produced. The electrophotographic photosensitive member thus obtained is designated as P3. Example 4 In Example 3, 1,8-naphthalic anhydride (NAD) was used.
With a polycarbonate resin / NAD weight ratio of 100/5
An electrophotographic photoreceptor was prepared in the same manner as in Example 3 except that the addition was performed so that The electrophotographic photosensitive member thus obtained is designated as P4. Example 5 The same procedure as in Example 1 was carried out except that 1,8-naphthalenedicarboximide (NAI) was added in place of NTCDA so that the weight ratio of polycarbonate resin / NAI was 100/3. A photoreceptor was prepared.
The electrophotographic photosensitive member thus obtained is designated as P5. Example 6 An electrophotographic photosensitive member was prepared in the same manner as in Example 5, except that 1,8-naphthalenedicarboximide (NAI) was added so that the weight ratio of polycarbonate resin / NAI was 100/5. Produced. The electrophotographic photosensitive member thus obtained is designated as P6. Comparative Example 1 An electrophotographic photosensitive member was produced in the same manner as in Example 1 except that NTCDA was not added. The electrophotographic photosensitive member thus obtained is designated as Q1.

Next, the electrophotographic photosensitive members produced in Examples 1 to 6 and Comparative Example 1 were mounted on a photosensitive member characteristic measuring device [Model EPA8100 manufactured by Kawaguchi Electric Co., Ltd.], and the current flowing into the aluminum surface was 25 μA. After charging so that
Exposure and static elimination are performed, and the chargeability (Vo) at that time, the rate of decrease in the potential after standing for 2 seconds from the start of charging (dark decay DD), the half-exposure amount (E1 / 2 reference potential: -450 V), the residual potential (Vr) ) Was measured. Next, the dynamic friction coefficient of the surface of the electrophotographic photosensitive member was measured. The measurement was performed by applying 0.1% of toner on the photosensitive layer surface.
mg / cm ^2, and then urethane rubber having a thickness of 2 mm and cut to a width of 1 cm was pressed against the surface of the photoreceptor at an angle of 45 ° to measure the friction coefficient. The load was 200 g, and the speed was 5 mm / sec. DFPM-, an automatic friction coefficient abrasion tester manufactured by Kyowa Interface Chemical Co., Ltd. under the conditions of a stroke of 20 mm and a repetition of 100 times.
SS was used. Next, the decrease in the amount of wear after opening 1000 was measured using a wear wheel (CS-10F) with a Taber abrasion tester. Next, Examples 1 and 2 were placed on a pet film.
And after applying the coating solution of Comparative Example 1 with an applicator,
The resultant was dried at room temperature for 20 minutes, and further dried at 125 ° C. for 20 minutes to form a charge transport film so that the dry film pressure became 20 μm. Next, 900nm, 780nm, 660nm, 540n
The transmittance (% T) at m and 420 nm was measured with a spectrophotometer (manufactured by HITACHI, product name U-3210). The results are shown in Table 1.

[0044]

[Table 1]

[0045]

According to the present invention, it is possible to provide an electrophotographic photoreceptor having excellent durability and excellent electrical properties, and a coating solution for producing the same.

 ────────────────────────────────────────────────── ─── Continuing from the front page (72) Inventor Protector 1000 Kamoshita-cho, Aoba-ku, Yokohama-shi, Kanagawa Prefecture Mitsubishi Chemical Corporation Yokohama Research Laboratory F-term (reference) 2H068 AA13 AA14 AA20 AA37 BA12 BA14 BA16 BA39 BB25 BB27 BB52

Claims (11)

[Claims] 1. An electrophotographic photoreceptor comprising a charge generating layer and a charge transport layer sequentially laminated on a conductive support, wherein the charge transport layer contains a condensed polycyclic compound having a molecular weight of 150 to 1000 as a main component. An electrophotographic photoreceptor characterized by containing particles. 2. The electrophotographic photoconductor according to claim 1, wherein the condensed polycyclic compound is represented by the following general formula (I). Embedded image (In the formula (I), Y represents a sulfur atom, an oxygen atom or -NR ¹⁷
And R ¹⁷ represents an alkyl group which may have a substituent, an aryl group which may have a substituent, or an aralkyl group which may have a substituent. R ^{11 to} R ¹⁶
Are each independently an alkyl, alkenyl, aryl, aralkyl, carboxyl, alkoxycarbonyl, hydroxyalkyl, aminoalkyl, aminocarbonyl, N-alkylaminocarbonyl,
Represents an N-arylaminocarbonyl group. In addition, R ¹¹ ~
R ¹⁶ may bond or condense with each other to form a cyclic structure. ) 3. The fused polycyclic compound is a C ₂ space group or Cs
3. The electrophotographic photoreceptor according to claim 1, which belongs to a space group. 4. The electrophotographic photoreceptor according to claim 1, wherein particles having a condensed polycyclic compound as a main component have an average particle diameter of 1 to 30 μm. 5. The electrophotographic photoreceptor according to claim 1, wherein the binder resin of the charge transport layer is polycarbonate or polyarylate. 6. The charge transport layer according to the following general formula (II)
The charge transport material according to any one of claims 1 to 5, wherein
Electrophotographic photoreceptor. Embedded image(In the general formula (II), Ar¹Is an optionally substituted
Benzene ring, an optionally substituted naphthalene ring, or
Represents a biphenyl ring which may be substituted; ^Two~ A
r^FiveEach independently represents an optionally substituted aromatic ring
Represent. ) 7. The electrophotographic photoreceptor according to claim 1, wherein the charge generation layer contains oxytitanium phthalocyanine. 8. The electrophotographic photosensitive member according to claim 1, wherein the charge transport layer is an outermost layer. 9. A coating solution for a charge transport layer containing at least a charge transport material, a binder resin, and particles mainly composed of a condensed polycyclic compound having a molecular weight of 150 to 1,000. 10. The coating solution has a viscosity of 50 to 1000 cps.
The coating solution for a charge transport layer according to claim 9, wherein 11. A method for producing an electrophotographic photoreceptor comprising a charge generation layer and a charge transport layer sequentially laminated on a conductive support, wherein the charge transport layer is immersed using the charge transport layer coating solution according to claim 9 or 10. A method for producing an electrophotographic photoreceptor, wherein a charge transport layer is provided by coating.