JPH11174699A - Electro-photoreceptor and electrophotographic device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide high abrasion resistance and high durability even in the case of using a process such as a contact charging device by including a specified diol group and a specified dicarboxylic acid group or polyester polymer in a photosensitive layer as a bonding resin. SOLUTION: A diol group containing diol expressed by formula I and/or diol expressed by formula II, a carboxylic acid group containing 2,6-naphthalene dicarboxylic acid or polyester polymer polymerized from the ester forming derivative thereof are used. In formula I, R1 is a 1-4C alkylene group; R2 , R3 are separately hydrogen or a 1-7C alkyl group or an arly group; R4 -R7 are separately hydrogen a 1-7C alkyl group, a cycloalkane group or an aryl group. In formula II, R8 is a 1-4C alkylene group; R9 is direct bonding or a 1-7C alkylene group; R10 -R11 are separately hydrogen, a 1-7C alkyl group, cycloalklane group or an aryl group; and (m) is a natural number 1-9.

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 using a polyester polymer having a specific structure as a binder resin for a photosensitive layer, and an electrophotographic photoreceptor having a specific structure. The present invention relates to an electrophotographic photosensitive member to which a benzidine compound and / or a triarylamine compound is added as a charge transporting agent, and an electrophotographic apparatus using the photosensitive member.

[0002]

2. Description of the Related Art Electrophotographic photoreceptors are widely used in the fields of copiers, laser beam printers, and the like because of their high speed and high printing quality. Conventionally, inorganic photoconductive materials such as selenium, selenium-tellurium alloy, selenium-arsenic alloy, and cadmium sulfide have been used as constituent materials of electrophotographic photoreceptors used in these electrophotographic apparatuses. Electrophotographic photoreceptors using organic photoconductive materials which are inexpensive, have good manufacturability and can be disposed of have become dominant. Among them, a function-separated type laminated organic photoreceptor in which a charge generation layer that generates charges by exposure and a charge transport layer that transports charges are laminated is excellent in electrophotographic characteristics such as electric sensitivity, chargeability, and its repetition stability. Various proposals have been made and put to practical use.

[0003]

However, a photoreceptor using an organic photoconductive material generally has poorer mechanical strength than a photoreceptor made of an inorganic photoconductive material, and has a low mechanical strength, such as a cleaning blade, a developing brush, and paper. Abrasion or abrasion is caused or abraded by a mechanical external force, and the electrical characteristics of the photoreceptor deteriorate due to the abrasion or the like. Furthermore, the point that uniform charging distribution can be obtained at low applied voltage, and in the system using the contact charging method that has been used recently from the viewpoint of ecology, the abrasion of the photoconductor increases significantly compared to the charging method using corotron. However, the above-mentioned problem becomes more serious. As the wear of the photoconductor progresses,
The sensitivity of the photoreceptor is reduced to cause fogging in the copy, and the charge potential is reduced to lower the copy density. Therefore, development of a surface layer material such as a binder resin and a charge transporting material that can form a photosensitive layer having sufficient durability is desired.

Further, a flexible electrophotographic photosensitive member in which a coating of a photosensitive layer is formed on a film such as polyethylene terephthalate having a conductive layer formed by a method such as vapor deposition,
Since the electrophotographic apparatus can be repeatedly used after being processed into a belt shape, it has the advantage that the degree of freedom in the shape of the electrophotographic apparatus can be increased, but the photoconductor must sufficiently follow flexible movement. There is a request that.
Therefore, a photoreceptor using various polycarbonate resins as a binder resin of the photoreceptor surface layer has been proposed (JP-A-60-1985).
172044 JP, JP-A-62-247374, JP-A-63-1482
No. 63).

However, when a coating film of a photosensitive layer is formed by a coating process using a conventionally proposed binder resin, a belt-shaped electrophotographic photosensitive member having relatively good durability can be obtained, but the mechanical properties of the belt-shaped electrophotographic photosensitive member can be obtained. The strength is not always at a sufficient level, and when repeatedly rotated for a long time in a belt drive device in a copying machine, cracks occur in the photosensitive layer, which appears as cracks on the copied image. The problem remained.

[0006] The present invention has been made in view of the above situation, and has as its object to solve the above-mentioned problems in the prior art.

That is, a first object of the present invention is to provide an electrophotographic photosensitive member having high abrasion resistance and having high durability even when a process such as a contact charging device is used.

A second object of the present invention is to provide a coating film on the surface of a photoreceptor which has high flexibility, and when used repeatedly as a belt-shaped photoreceptor, does not cause defects such as cracks in the coating film. Another object of the present invention is to provide an electrophotographic photosensitive member having excellent durability by having high abrasion resistance.

In order to solve such a problem, it is important to use not only a binder resin but also a charge transport material that maximizes the mechanical properties of the resin.

[0010]

Means for Solving the Problems The present inventors have made various studies in view of the above points, and as a result, as a binder resin for a photosensitive layer, a diol represented by the following general formula 1 and / or a general formula 2
Of mechanical strength in electrophotographic photoreceptors using polyester polymers polymerized from diols containing diols and dicarboxylic acids containing 2,6-naphthalenedicarboxylic acid or their ester-forming derivatives In addition, when a benzidine compound represented by the general formula 3 and / or a triarylamine compound represented by the general formula 4 is used as the charge transport agent, the compound has extremely excellent durability characteristics; and By using these materials, it is possible to solve the problem of mechanical deterioration of the photosensitive layer in a drum-shaped photoreceptor and a belt-shaped photoreceptor when rotated repeatedly for a long time in an electrophotographic apparatus. They have found and completed the present invention.

That is, the present invention relates to an electrophotographic photoreceptor comprising a photosensitive layer provided on a conductive support, wherein a diol represented by the following general formula 1 and / or a general formula 2 A diol group containing a diol represented by
Use of a polyester polymer polymerized from a dicarboxylic acid group containing 6-naphthalenedicarboxylic acid or an ester-forming derivative thereof, and preferably a benzidine compound represented by the general formula 3 and / or a general formula 4 as a charge transport agent An electrophotographic photoreceptor characterized by using a triarylamine-based compound represented by the formula: General formula 1:

Embedded image R ₁ is an alkylene group having 1 to 4 carbon atoms, R ₂ and R ₃ are each independently, hydrogen or an alkyl group having 1 to 7 carbon atoms, an aryl group, R _{4 to} R ₇ are each independently, hydrogen or Represents an alkyl group, cycloalkane group, or aryl group having 1 to 7 carbon atoms. General formula 2:

Embedded image R ₈ is an alkylene group having 1 to 4 carbon atoms, R ₉ is a direct bond or an alkylene group having 1 to 7 carbon atoms, R _{10 to} R ₁₄ are each independently, hydrogen or an alkyl group having 1 to 7 carbon atoms, cyclo An alkane group, an aryl group, and m represent a natural number of 1 to 9. General formula 3:

Embedded image R ₁ and R ₂ may be the same or different and include a hydrogen atom,
Alkyl group, an alkoxy group, a halogen atom, R ₃ ~
R ₆ may be the same or different and represents a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom or a substituted amino group. K to n each represent an integer of 1 or 2. General formula 4:

Embedded image R _{1 to} R ₂ may be the same or different and represent a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom, m and n
Represents an integer of 1 or 2, respectively. R ₃ represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or an aryl group having 6 to 12 carbon atoms.

In addition, for adaptation to a high-speed electrophotographic apparatus requiring high durability, the Bragg angle (2θ ± 0.2) of an X-ray diffraction spectrum using Cukα ray as a charge generation material is used.
°) at least 7.4 °, 16.6 °, 25.5 °, 28.3
Chlorgallium phthalocyanine with a diffraction peak at ° position, at least 7.5 °, 9.9 °, 12.5 °, 16.3 °,
Hydroxygallium phthalocyanine with diffraction peaks at 18.6 °, 25.1 °, 28.1 °, at least 9.5
It is more preferable to have a compound selected from titanyl phthalocyanine having diffraction peaks at positions of °, 11.7 °, 15.0 °, 24.1 °, and 27.3 °.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An example of the constitution of a photoreceptor obtained by the present invention will be described below. FIGS. 1 to 7 respectively show a photoreceptor employing a function separation layered structure, a photoreceptor having a function separation layered structure provided with an undercoat layer, a photoreceptor having a function separation layered structure provided with a protective layer, an undercoat layer, and a protective layer. Of a photoreceptor having a function-separated laminated structure having a layer, a photoreceptor having a single-layer structure, a photoreceptor having a single-layer structure having an undercoat layer, and a single-layer structure having a sublayer and a protective layer. It is an expanded sectional schematic diagram which shows an example.

In the electrophotographic photoreceptor of the present invention, as the conductive support 3, a metal drum such as aluminum, copper, iron, zinc, nickel or an alloy such as SUS,
Aluminum, copper, gold, silver, platinum, palladium, titanium, nickel on sheet, paper, plastic or glass
Metal such as chromium, stainless steel, copper-indium, or conductive metal compound such as indium oxide / tin oxide, metal foil laminated, or carbon black / indium oxide / tin oxide-oxidation A known material such as a drum-shaped, sheet-shaped, or plate-shaped material that has been subjected to conductive treatment by dispersing antimony powder, metal powder, copper iodide, and the like in a binder resin and applying the dispersion can be used.

In the case of using a metal pipe base material, even if the surface of the base material is a raw pipe, it is necessary to perform mirror cutting, etching,
Anodizing, rough cutting, centerless grinding, sand blasting,
Processing such as wet honing may be performed. By roughening the surface of the base material by the surface treatment, it is possible to prevent grain-like density unevenness due to interference light in the photoconductor, which may occur when a coherent light source such as a laser beam is used.

The undercoat layer 4 provided on the surface of the conductive support 3 is made of an acetal resin such as polyvinyl butyral, polyvinyl alcohol resin, casein, polyamide resin, cellulose resin, gelatin, polyurethane resin, polyester resin, methacrylic resin, acrylic resin, In addition to high-molecular resin compounds such as polyvinyl chloride resin, polyvinyl acetate resin, vinyl chloride-vinyl acetate-maleic anhydride resin, silicone resin, silicone-alkyd resin, phenol-formaldehyde resin, and melamine resin,
Zirconium, titanium, aluminum, manganese,
Examples include organometallic compounds containing silicon atoms and the like. These compounds can be used alone or as a mixture or a polycondensate of a plurality of compounds. Above all, organometallic compounds containing zirconium or silicon are excellent in performance such as low residual potential, little potential change due to environment, and little change in potential due to repeated use.

Examples of the silicon-containing compound include, for example, vinyltrimethoxysilane, γ-methacryloxypropyl-tris (β-methoxyethoxy) silane,
(3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, vinyltriacetoxysilane, γ-mercaptopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, N-β- (amino Ethyl) -γ-aminopropyltrimethoxysilane, N-β- (aminoethyl) -γ-aminopropylmethylmethoxysilane, N, N-bis (β-hydroxyethyl) -γ-aminopropyltriethoxysilane, γ- Chloropropyltrimethoxysilane and the like. Among these, particularly preferred silicon compounds are vinyltriethoxysilane, vinyltris (2-methoxyethoxysilane), 3-methacryloxypropyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane,
(3,4-epoxycyclohexyl) ethyltrimethoxysilane, N-2- (aminoethyl) 3-aminopropyltrimethoxysilane, N-2- (aminoethyl) 3-aminopropylmethyldimethoxysilane, 3-aminopropyltrimethoxysilane Examples include silane coupling agents such as ethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, and 3-chloropropyltrimethoxysilane.

Examples of the organic zirconium compound include zirconium butoxide, ethyl zirconium acetoacetate,
Zirconium triethanolamine, acetylacetonate zirconium butoxide, ethyl zirconium butoxide acetoacetate, zirconium acetate, zirconium oxalate, zirconium lactate, zirconium phosphonate, zirconium octoate, zirconium naphthenate, zirconium laurate, zirconium stearate, zirconium isostearate, Examples include methacrylate zirconium butoxide, stearate zirconium butoxide, isostearate zirconium butoxide, and the like.

Examples of the organic titanium compound include tetraisopropyl titanate, tetranormal butyl titanate, butyl titanate dimer, tetra (2-ethylhexyl) titanate, titanium acetylacetonate, polytitanium acetylacetonate, titanium octylene glycolate, titanium lactate Examples thereof include ammonium salts, titanium lactate, titanium lactate ethyl ester, titanium triethanolamine, and polyhydroxytitanium stearate. Examples of the organic aluminum compound include aluminum isopropylate, monobutoxyaluminum diisopropylate, aluminum butyrate, diethyl acetoacetate aluminum diisopropylate, and aluminum tris (ethyl acetoacetate).

In the undercoat layer 4, various organic or inorganic fine powders can be mixed for the purpose of improving electric characteristics and light scattering. In particular, white pigments such as titanium oxide, zinc oxide, zinc white, zinc sulfide, lead white, and lithopone; inorganic pigments such as alumina, calcium carbonate, and barium sulfate; and Teflon resin particles, benzoguanamine resin particles, and styrene resin particles Etc. are effective.
The particle size of the added fine powder is from 0.01 to 2 μm. The thickness of the undercoat layer 4 is preferably in the range of 0.1 to 10 μm.

The above-mentioned various fine powders are added as required.
It is added in a weight ratio of 10 to 80% by weight, more preferably 30 to 70% by weight.

In the formation of the coating liquid for the undercoat layer 4, when mixing the added fine powder, it is added to a solution in which a resin component is dissolved to perform a dispersion treatment. As a method of dispersing the added fine powder in the resin, a method such as a roll mill, a ball mill, a vibration ball mill, an attritor, a sand mill, a colloid mill, and a paint shaker can be used.

The photosensitive layer 6 formed on the undercoat layer 4 has a single-layer structure as shown in FIG.
As shown in Nos. 1 to 4, the charge generating layer 1 and the charge transport layer 2 may have a stacked structure in which functions are separated. In the case of a laminated structure, the charge generating layer 1 and the charge transporting layer 2 are stacked in an order that the charge transporting layer 2 is an upper layer as shown in the drawing in order to utilize the combination of the binder resin and the charge transporting material of the present invention. Is preferred. Further, if necessary, the surface protective layer 5 can be formed as shown in FIG.

By using the present invention, the photoreceptor having the structure in which the charge transport layer 2 is the surface layer can improve the abrasion resistance of the photoreceptor and reduce the surface scratches. No matter where in the top or bottom of the configuration, the mechanical life for flexibility can be increased. In addition, excellent electrical characteristics and image quality can be obtained regardless of the configuration.

The charge generating layer 1 is formed by forming a charge generating substance by vacuum evaporation or by dispersing and applying a charge generating substance together with an organic solvent and a binder resin.

As the charge generating material, amorphous selenium, crystalline selenium, selenium-tellurium alloy, selenium-arsenic alloy,
Other selenium compounds and selenium alloys, inorganic photoconductors such as zinc oxide and titanium oxide, various phthalocyanine pigments such as metal-free phthalocyanine, titanyl phthalocyanine, copper phthalocyanine, tin phthalocyanine, gallium phthalocyanine, squarium, anthantrone, Various organic pigments and dyes such as perylene-based, azo-based, anthraquinone-based, pyrene-based, pyrylium salts, and thiapyrylium salts are used. In addition, these organic pigments generally have several types of crystal forms, particularly phthalocyanine pigments α-type,
Various crystal types such as β type are known, but if it is a pigment that can obtain the desired sensitivity,
Any of these crystal forms can be used.

In the present invention, the following compounds may be mentioned as charge generation materials which can obtain particularly excellent performance in relation to the polyester polymer and the charge transport material used in the charge transport layer 2.

In the Bragg angle (2θ ± 0.2 °) of the X-ray diffraction spectrum using Cukα ray as the charge generating material,
Chlorgallium phthalocyanine having diffraction peaks at least at positions of 7.4 °, 16.6 °, 25.5 °, and 28.3 °.

At the Bragg angle (2θ ± 0.2 °) of the X-ray diffraction spectrum using Cukα ray as the charge generating material,
At least 7.5 °, 9.9 °, 12.5 °, 16.3 °, 18.6 °, 2
Hydroxygallium phthalocyanine having diffraction peaks at 5.1 ° and 28.1 °.

At the Bragg angle (2θ ± 0.2 °) of the X-ray diffraction spectrum using Cukα ray as the charge generating material,
Titanyl phthalocyanine having diffraction peaks at at least 9.5 °, 11.7 °, 15.0 °, 24.1 °, 27.3 °.

As the binder resin in the charge generation layer 1,
The following can be exemplified. That is, a polyester polymerized from a diol group containing a diol having the structure shown in the general formula 1 and / or a diol group containing a diol having a structure shown in the general formula 2, and a dicarboxylic acid group containing 2,6-naphthalenedicarboxylic acid or an ester-forming derivative thereof. Resins, other polyester resins, polyarylate resins, methacrylic resins, acrylic resins, polyvinyl chloride resins, polystyrene resins, polyvinyl acetate resins, styrene-butadiene copolymer resins, vinylidene chloride-acrylonitrile copolymer resins, vinyl chloride- Vinyl acetate-maleic anhydride resin, silicone resin, silicon-alkyd resin, phenol-formaldehyde resin, styrene-alkyd resin, poly-N-vinylcarbazole and the like.

These binder resins can be used alone or in combination of two or more. The mixing ratio (weight ratio) of the charge generation material and the binder resin is preferably in the range of 10: 1 to 1:10. The thickness of the charge generation layer 1 is generally 0.01 to 5
μm, preferably in the range of 0.05 to 2.0 μm.

As a method of dispersing the charge generating material in the resin, a method such as a roll mill, a ball mill, a vibration ball mill, an attritor, a dyno mill, a sand mill, a colloid mill, and a homogenizer can be used.

The binder resin used for the charge transport layer 2 includes a diol group containing a diol represented by the following general formula 1 and / or a diol group containing a diol represented by the following general formula 2, and a dicarboxylic acid containing 2,6-naphthalenedicarboxylic acid. Polyester polymers which are polymerized from the group or their ester-forming derivatives are used. General formula 1:

Embedded image R ₁ is an alkylene group having 1 to 4 carbon atoms, R ₂ and R ₃ are each independently, hydrogen or an alkyl group having 1 to 7 carbon atoms, an aryl group, R _{4 to} R ₇ are each independently, hydrogen or Represents an alkyl group, cycloalkane group, or aryl group having 1 to 7 carbon atoms. General formula 2:

Embedded image R ₈ is an alkylene group having 1 to 4 carbon atoms, R ₉ is a direct bond or an alkylene group having 1 to 7 carbon atoms, R _{10 to} R ₁₄ are each independently, hydrogen or an alkyl group having 1 to 7 carbon atoms, cyclo An alkane group, an aryl group, and m represent a natural number of 1 to 9.

Specific examples of the diol having the structure represented by the general formula 1 are shown in Tables 1 to 5 below.

[Table 1]

[0036]

[Table 2]

[0037]

[Table 3]

[0038]

[Table 4]

[0039]

[Table 5]

Tables 6 and 7 show specific examples of the diol represented by the general formula 2. General formula 2:

Embedded image R ₈ is an alkylene group having 1 to 4 carbon atoms, R ₉ is a direct bond or an alkylene group having 1 to 7 carbon atoms, R _{10 to} R ₁₄ are each independently, hydrogen or an alkyl group having 1 to 7 carbon atoms, cyclo An alkane group, an aryl group, and m represent a natural number of 1 to 9.

[Table 6]

[0041]

[Table 7]

In the polyester copolymer used as the binder resin of the charge transport layer 2 of the present invention, the content of the diol represented by the general formula 1 and / or 2 with respect to the total diol is preferably 30 mol% or more. Preferably, the content is 50 mol% or more. If the content is less than 30 mol%, the effects of the diol represented by the general formula 1 and / or the general formula 2 cannot be sufficiently exerted, and high abrasion resistance and good electrical properties cannot be realized.

In the polyester polymer used as the binder resin of the charge transport layer 2 of the present invention, known diols can be used as the diols other than the diols represented by the general formulas 1 and 2. Is mentioned.

That is, aliphatic diols such as ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol and 1,6-hexanediol;
1,4-cyclohexanedimethanol, tricyclodecanedimethylol, 1,1'-bis (4- (2-hydroxyethoxy)
Alicyclic diols such as cyclohexan), 2,2-bis (4- (2-hydroxyethoxy) cyclohexyl) propane,
1,4-bis (hydroxymethoxy) benzene, 1,4-bis (hydroxymethoxy) benzene, 1,3-bis (hydroxymethoxy) benzene, 1,2-bis (hydroxymethoxy) benzene, 2,6-bis ( (Hydroxymethoxy) naphthalene, 2,7-bis (hydroxymethoxy) naphthalene,
3-bis (hydroxymethoxy) naphthalene, 2,5-bis (hydroxymethoxy) naphthalene, 1,2-bis (hydroxymethoxy) naphthalene, 1,3-bis (hydroxymethoxy) naphthalene, 1,4-bis (hydroxymethoxy ) Naphthalene, 1,5-bis (hydroxymethoxy) naphthalene, 1,6-bis (hydroxymethoxy) naphthalene, 1,7-
Bis (hydroxymethoxy) naphthalene, 1,8-bis (hydroxymethoxy) naphthalene, 2,4-bis (hydroxymethoxy) naphthalene, 4,4′-bishydroxy-1,1′-biphenol, 4,3′-bis Hydroxy-1, 1'-biphenol, 4,2'-bishydroxy-1, 1'-biphenol, 3,3'-bishydroxy-1, 1'-biphenol, 3,2'-bishydroxy-1, 1 Aromatic diols such as' -biphenol, 2,2'-bishydroxy-1, 1'-biphenol, 9,9-bis (4- (2-hydroxyethoxy) phenyl) fluorene, 2,2-bis (4 -(2-hydroxyethoxyphenyl) -4-methyl-pentane, 3,3-bis (4- (2-hydroxyethoxyphenyl)
and bisphenol derivatives such as -n-pentane, 2,2-bis (4- (2-hydroxyethoxyphenyl) -n-octane, and bis (4- (2-hydroxyethoxyphenyl) sulfone.

These diols may be used alone or in combination of two or more as needed. Among these, ethylene glycol is particularly preferred in terms of polymerization reactivity and coloring.

The dicarboxylic acid or its ester-forming derivative used in the polyester polymer used as the binder resin of the charge transport layer 2 of the present invention is 2,6-naphthalenedicarboxylic acid or its 2,6-naphthalenedicarboxylic acid because of its high mechanical properties. It must contain an ester-forming derivative.

The content of 2,6-naphthalenedicarboxylic acid or its ester-forming derivative relative to the total dicarboxylic acid component in the polymer is preferably at least 30 mol%, more preferably at least 50 mol%. When the content is less than 30 mol%, the mechanical strength of the polyester polymer becomes insufficient, and when this is used as a binder resin for the photosensitive layer, the abrasion resistance of the photoconductor becomes insufficient.

Known dicarboxylic acids or ester-forming derivatives thereof other than 2,6-naphthalenedicarboxylic acid or its ester-forming derivative used in the polyester polymer used as the binder resin of the charge transport layer 2 of the present invention are known. The following can be used, for example.

That is, aliphatic dicarboxylic acids such as succinic acid, maleic acid, adipic acid, sebacic acid, decamethylene dicarboxylic acid, and ester-forming derivatives thereof,
Alicyclic dicarboxylic acids such as cyclohexanedicarboxylic acid, 2,6-dicyclodecanedicarboxylic acid, and tricyclodecanedicarboxylic acid and ester-forming derivatives thereof, terephthalic acid, isophthalic acid, 1,2-benzenedicarboxylic acid, 2,7 -
Naphthalenedicarboxylic acid, 2,3-naphthalenedicarboxylic acid, 2,4-naphthalenedicarboxylic acid, 2,5-naphthalenedicarboxylic acid, 2,8-naphthalenedicarboxylic acid, 1,2-naphthalenedicarboxylic acid, 1,3-naphthalenedicarboxylic acid Acid, 1,4-naphthalenedicarboxylic acid, 1,5-naphthalenedicarboxylic acid,
Examples thereof include aromatic dicarboxylic acids such as 1,6-naphthalenedicarboxylic acid and 1,8-naphthalenedicarboxylic acid, and ester-forming derivatives thereof.

These dicarboxylic acids or their ester-forming derivatives may be used alone or, if necessary,
A combination of more than two types may be used. Among these,
In particular, succinic acid and terephthalic acid are particularly preferred in terms of polymerization reactivity and coloring.

The molecular weight of the polymer used in the present invention is appropriately selected depending on the film thickness of the photosensitive layer, film forming conditions such as a solvent, and mechanical properties such as abrasion resistance. The range is preferably from 200,000 to 200,000, more preferably from 40,000 to 100,000. When the weight average molecular weight is 30,000 or less, the mechanical strength of the resin decreases, and the abrasion resistance decreases. When the weight average molecular weight exceeds 300,000, the function of the charge transporting material is reduced, and not only the electrical sensitivity is reduced, but also the film forming property is deteriorated and the surface properties of the photoreceptor are deteriorated.

In the present invention, in order to exhibit high abrasion resistance and to realize excellent electric characteristics in combination with a polyester polymer used as a binder resin in the charge transport layer 2, the following general formula 3 And / or a triarylamine compound represented by the general formula 4 is preferably used. General formula 3:

Embedded image R ₁ and R ₂ may be the same or different and include a hydrogen atom,
Alkyl group, an alkoxy group, a halogen atom, R ₃ ~
R ₆ may be the same or different and represents a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom or a substituted amino group. K to n each represent an integer of 1 or 2. General formula 4:

Embedded image R _{1 to} R ₂ may be the same or different and represent a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom, m and n
Represents an integer of 1 or 2, respectively. R ₃ represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or an aryl group having 6 to 12 carbon atoms.

Specific examples of the benzidine compound represented by the general formula 3 are shown in Tables 8 to 10.

[Table 8]

[0054]

[Table 9]

[0055]

[Table 10]

Specific examples of the triarylamine-based compound represented by the general formula 4 are shown in Tables 11 to 13.

[Table 11]

[0057]

[Table 12]

[0058]

[Table 13]

In the present invention, when a benzidine compound represented by the general formula 3 and / or a triarylamine compound represented by the general formula 4 is used as a charge transport material, other charge transport materials such as fluorenone Very excellent abrasion resistance and electrical characteristics can be obtained as compared with the case of using a compound or a carbazole compound.

Further, even if the compound is a benzidine compound, for example, a benzidine compound not included in the general formula 3 as shown in the chemical formula 7, or a triarylamine compound, for example, When a triarylamine-based compound not included in the general formula 4 as shown is used as the charge transporting material, the abrasion resistance and electric characteristics are higher than when the compound of the general formula 3 and / or 4 is used. Can not get. Although the reason is not clear, for example, a benzidine compound represented by the chemical formula 7 and a triarylamine compound represented by the chemical formula 8 are:
To make the molecule too large to improve the charge transport ability,
It is estimated that the abrasion resistance due to the mechanical strength derived from the intermolecular force of the binder resin was reduced. General formula 7:

Embedded image General formula 8:

Embedded image

In order to prevent the deterioration of the photoreceptor due to ozone or oxidizing gas generated in the electrophotographic apparatus, or light and heat, additives such as antioxidants, light stabilizers and heat stabilizers are added to the photosensitive layer. Can be added.

For example, examples of the antioxidant include hindered phenol, hindered amine, paraphenylenediamine, arylalkane, hydroquinone, spirochroman, spiroidanone and derivatives thereof, organic sulfur compounds and organic phosphorus compounds.

As a specific compound example of the antioxidant, phenolic antioxidants include 2,6-di-t-butyl-4-methyl
Phenol, styrenated phenol, n-octadecyl-3
-(3 ', 5'-di-t-butyl 4'-hydroxyphenyl) -propionate, 2,2'-methylene-bis- (4-methyl-6-t-butyl
Phenol), 2-t-butyl-6- (3'-t-butyl-5'-methyl-
2'-hydroxybenzyl) -4-methylphenyl acrylate, 4,4'-butylidene-bis- (3-methyl-6-t-butyl-phenol), 4,4'-thio-bis- (3-methyl6 -t-butylphenol), 1,3,5-tris (4-t-butyl-3-hydroxy-2,6-dimethylbenzyl) isocyanurate, tetrakis- [methylene-3- (3 ', 5'-di- t-butyl-4'-hydroxy-phenyl)
Propionate] -methane, 3,9-bis [2- [3- (3-t-butyl-
4-hydroxy-5-methylphenyl) propionyloxy]
-1,1-dimethylethyl] -2,4,8,10-tetraoxaspiro
[5,5] undecane and the like. Hindered amine compounds include bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate, bis (1,2,2,6,6-pentamethyl-4-piperidyl) sebacate, 1- [2- [3 -(3,5-di-t-butyl-4-hydroxyphenyl) propionyloxy] ethyl] -4- [3- (3,
5-di-t-butyl-4-hydroxyphenyl) propionyloxy] -2,2,6,6-tetramethylpiperidine, 8-benzyl-
7,7,9,9-Tetramethyl-3-octyl-1,3,8-triazaspiro [4,5] undecane-2,4-dione, 4-benzoyloxy-
2,2,6,6-tetramethylpiperidine, dimethyl succinate-1
-(2-hydroxyethyl) -4-hydroxy-2,2,6,6-tetramethylpiperidine polycondensate, poly [{6- (1,1,3,3-tetramethylbutyl) imino-1,3 , 5-Triazine-2,4-diimyl}
{(2,2,6,6-tetramethyl-4-piperidyl) imino} hexamethylene {(2,3,6,6-tetramethyl-4-piperidyl) imino}], 2- (3,5-di -t-butyl-4-hydroxybenzyl) -2-n
-Butylmalonate bis (1,2,2,6,6-pentamethyl-4-piperidyl), N, N'-bis (3-aminopropyl) ethylenediamine-2,4-bis [N-butyl-N- ( 1,2,2,6,6, -pentamethyl-4
Piperidyl) amino] -6-chloro-1,3,5-triazine condensate and the like. Dilauryl-3,3'-thiodipropionate, dimyristyl-3,
3'-thiodipropionate, distearyl-3,3'-thiodipropionate, pentaerythritol-tetrakis-
(β-lauryl-thiopropionate), ditridecyl-3,
3'-thiodipropionate, 2-mercaptobenzimidazole and the like. Examples of the organic phosphorus antioxidant include trisnonylphenyl phosphite, triphenyl phosphite, and tris (2,4-di-t-butylphenyl) -phosphite.

The organic sulfur and organic phosphorus antioxidants are 2
A synergistic effect can be obtained when used in combination with a primary antioxidant such as a phenolic or amine-based antioxidant.

Examples of the light stabilizer include benzophenone, benzotriazole, dithiocarbamate, and tetramethylpiperidine derivatives.

Examples of the benzophenone-based light stabilizer include 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-octoxybenzophenone, and 2,2'-dihydroxy-4-methoxybenzophenone. 2-(-2'-hydroxy-5'methylphenyl-)-benzotriazole, 2- [2'-hydroxy-3'-
(3 '', 4 '', 5 '', 6 ''-tetra-hydrophthalimide-methyl)
-5'-Methylphenyl] -benzotriazole, 2-(-2'-hydroxy-3'-t-butyl 5'-methylphenyl-)-5-chloro
Benzotriazole, 2- (2'-hydroxy-3'-t-butyl
5'-methylphenyl-)-5-chlorobenzotriazole, 2
-(2'-hydroxy-3 ', 5'-t-butylphenyl-)-benzotriazole, 2- (2'-hydroxy-5'-t-octylphenyl) -benzotriazole, 2- (2'-hydroxy 3 ', 5'-di-
t-Amyl phenyl-)-benzotriazole and the like. 2,4, di-t-butylphenyl as other compounds
3 ', 5'-di-t-butyl-4'-hydroxybenzoate, nickel dibutyl-dithiocarbamate and the like.

Further, at least one kind of electron accepting substance can be contained for the purpose of improving sensitivity, reducing residual potential, and reducing fatigue when repeatedly used. Examples of the electron-accepting substance that can be used in the photoreceptor of the present invention include succinic anhydride, maleic anhydride, dibromomaleic anhydride, phthalic anhydride, tetrabromophthalic anhydride, tetracyanoethylene, tetracyanoquinodimethane, and o. -Dinitrobenzene, m-dinitrobenzene, chloranil, dinitroanthraquinone, trinitrofluorenone, picric acid, o-
Nitrobenzoic acid, p-nitrobenzoic acid, phthalic acid and the like can be mentioned. Of these, fluorenone-based, quinone-based, and benzene derivatives having an electron-withdrawing substituent such as Cl, CN, and NO2 are particularly preferable.

The charge transport layer 2 can be formed by applying a solution obtained by dissolving the above-described charge transport material and binder resin in a suitable solvent and drying the solution. Examples of the solvent used for forming the charge transport layer 2 include aromatic hydrocarbons such as benzene, toluene, and chlorobenzene;
Ketones such as acetone and 2-butanone, halogenated aliphatic hydrocarbons such as methylene chloride, chloroform, and ethylene chloride; cyclic and linear ethers such as tetrahydrofuran, dioxane, ethylene glycol, and diethyl ether; or a mixed solvent thereof Etc. can be used. The compounding ratio of the charge transport material and the binder resin is 10: 1 to
1: 5 is preferred. The thickness of the charge transport layer 2 is generally 5 to 50.
μm, preferably in the range of 10 to 40 μm. When the film thickness is less than 5 μm, the influence of deterioration of the electrical characteristics of the photoconductor due to abrasion increases, and the life is shortened. 50μm film thickness
When the ratio exceeds, the charge transporting property is reduced.

In the present invention, a diol group containing the diol represented by the general formula 1 and / or a diol group containing the diol represented by the general formula 2 and a dicarboxylic acid containing 2,6-naphthalenedicarboxylic acid are used as the binder resin of the charge transport layer 2. Polyester polymers polymerized from groups or their ester-forming derivatives have the characteristic of exhibiting extremely low solution viscosities when dissolved in solvents. That is, in order to obtain the same solution viscosity, the solid content of the resin can be increased, that is, the amount of the solvent can be reduced, as compared with a conventional binder resin such as polycarbonate. This means that the amount of solvent used can be reduced for the same photoconductor production amount, which not only has the advantage of being environmentally friendly but also has the effect of cost reduction. Conversely, when using the same solid content as when using polycarbonate, the solution viscosity can be extremely reduced, and the productivity is significantly improved.

A small amount of silicone oil can be added to the coating solution as a leveling agent for improving the smoothness of the coating film.

Coating can be performed by a coating method such as a dip coating method, a ring coating method, a spray coating method, a bead coating method, a blade coating method, or a roller coating method, depending on the shape and application of the photoreceptor. . Drying is preferably performed by heat drying after touch drying at room temperature. Heat drying is 30 ° C ~ 200
It is desirable to carry out at a temperature of ° C. for a time ranging from 5 minutes to 2 hours.

A surface protective layer 5 can be formed on the photosensitive layer 6 (the charge generating layer 1 or the charge transport layer 2 in the case of a photosensitive member having a function-separated laminated structure) as required. Surface protective layer 5
For example, there is an insulating resin protective layer or a low resistance protective layer in which a resistance adjusting agent is added to the insulating resin. In the case of a low resistance protective layer, for example, a layer in which conductive fine particles are dispersed in an insulating resin can be used. As the conductive fine particles, fine particles having an electric resistance of 109 Ωcm or less and exhibiting white, gray or bluish white and having an average particle diameter of 0.3 μm or less, preferably 0.1 μm or less are suitable.For example, molybdenum oxide, tungsten oxide, antimony oxide , Tin oxide, titanium oxide, indium oxide, a carrier of a solid solution of tin oxide and antimony or antimony oxide or a mixture thereof, or a mixture of these metal oxides in a single particle, or a coating. . Among them, a solid solution of tin oxide, tin oxide and antimony or antimony oxide can be suitably adjusted in electric resistance, and can be made substantially transparent for the protective layer, and thus is preferably used ( See JP-A-57-30847 and JP-A-57-128344.

Examples of the insulating resin include condensation resins such as polyamide, polyurethane, polyester, epoxy resin, polyketone, and polycarbonate, and vinyl polymers such as polyvinyl ketone, polystyrene, and polyacrylamide.

The photoreceptor 7 obtained by the production method of the present invention is a light lens type copying machine, a laser beam printer emitting near-infrared light or visible light, a digital copying machine, an LE
It can be used for an electrophotographic apparatus such as a D printer and a laser facsimile.

FIG. 8 is a schematic sectional view of an electrophotographic apparatus according to the present invention. In this device, around the photoreceptor 7,
The contact type charging member 8 connected to the power supply 9, the image input device 10, the developing device 11, the transfer device 12, the cleaning device 13, and the static eliminator 14 are sequentially arranged.
Then, after the photoconductor 7 is charged by the charging member 8, an electrostatic latent image is formed on the photoconductor 7 by exposing the photoconductor 7 to light of a document, and then the electrostatic latent image is developed by the developing device 11. After obtaining a toner image and transferring it to a recording material such as transfer paper by a transfer device 12 to form an unfixed toner image on the recording material,
The fixing is performed by a fixing device 15 disposed at a position separated from the photoconductor 7 by a predetermined distance so that a fixed toner image is obtained.

As the charging member 8 for charging the photoreceptor, there is a non-contact type such as a corotron in addition to a contact type such as a charging roller or a charging brush as described above.
Charging with a contact-type charging member is preferable because a relatively low applied voltage is required and more uniform charging characteristics can be obtained. Therefore, when the photoreceptor according to the present invention is used as the photoreceptor 7, the abrasion resistance of the photoreceptor is high. It is possible to maintain good characteristics of the body and maintain its life for a long time. The photoreceptor is a one-component type,
It can be used in combination with a two-component regular developer or a reversal developer.

The synthesis examples of the polyester polymer used as the binder resin for the charge transport layer 2 and the like in the present invention are shown below.

The predetermined diol 28 represented by the following general formula 1
Mol, ethylene glycol 80 mol, 2,6-naphthalenedicarboxylic acid dimethyl ester 40 mol and zinc acetate 0.008
Moles into a 30 L polymerization apparatus, and the system was
Heat to ℃ to completely dissolve the contents. Then 40 ° C
The system is heated to 230 ° C. at a rate of / hour, and methanol, which is a reaction distillate, is distilled out of the system through a device such as a rectification column or a condenser.

When the theoretical amount of methanol has been distilled off, 0.032 mol of germanium oxide as a polymerization catalyst and 0.008 mol of trimethyl phosphoric acid as an antioxidant dispersed in ethylene glycol are added, and the mixture is stirred for about 30 minutes. The temperature of the system is gradually raised to 280 ° C. over 1 to 2 hours, and the pressure is reduced to a degree of vacuum of 1 Torr or less.

Further, the temperature of the system is maintained at 280 ° C. and the degree of vacuum is maintained at 1 Torr or less, and the increase in the stirring torque of the polymerization apparatus is recorded. When the stirring torque reaches a desired value, the polymerization is terminated.

The system is pressurized to about 5 kgf / cm 2 with nitrogen, and the polymer is extruded in a strand form through a base (a plurality of holes having an inner diameter of about 4 mm is opened) provided at the lower part of the polymerization apparatus. This is passed through a quench pool and pelletized with a rotary cutter. The obtained polymer may be subjected to purification such as reprecipitation, if necessary. General formula 1:

Embedded image R ₁ is an alkylene group having 1 to 4 carbon atoms, R ₂ and R ₃ are each independently, hydrogen or an alkyl group having 1 to 10 carbon atoms, an aryl group, R _{4 to} R ₇ are each independently, hydrogen or Represents an alkyl group, cycloalkane group or aryl group having 1 to 10 carbon atoms.

[0082]

EXAMPLES The present invention will now be described specifically with reference to examples, but the present invention is not limited to these examples.

Example 1 170 parts by weight of n-butyl alcohol in which 4 parts by weight of a polyvinyl butyral resin (Eslec BM-S manufactured by Sekisui Chemical) was dissolved, 30 parts by weight of an organic zirconium compound (acetylacetone zirconium butyrate) and an organic silane compound blend
3 parts by weight of (γ-aminopropyltrimethoxysilane) was additionally mixed and stirred to obtain a coating liquid for an undercoat layer. 30 mmφ roughened to a center line average roughness Ra = 0.18 μm by liquid honing using D50 30 μm alumina spherical fine powder
An undercoat layer was applied on the aluminum substrate of the ED tube using a dip coating apparatus, and a curing treatment was performed at 150 ° C. for 1 hour to form a 1.2 μm-thick undercoat layer.

7.4 °, 16.6 °, 25.5
°, a mixture consisting of 3 parts by weight of chlorogallium phthalocyanine having a clear X-ray diffraction peak at 28.3 °, 2 parts by weight of vinyl chloride vinyl acetate copolymer resin (Nippon Unicar VMCH), and 180 parts by weight of butyl acetate in a sand mill And dispersed for 4 hours. This solution was applied onto the undercoat layer 4 by dip coating and dried to form a charge generation layer having a thickness of 0.2 μm.

The binder resin for the charge transport layer is a polyester polymer synthesized according to the synthesis example, and the acid component is 70 mol% of dimethyl 2,6-naphthalenedicarboxylate,
A polyester polymer composed of 30 mol% of dimethyl terephthalate and 70 mol% of diol of compound No. 1-1 and 30 mol% of ethylene glycol as a diol component was used.

Next, N, N'-diphenyl-N, N'-bis (3-methylphenyl)-[1,1'-biphenyl] shown in Compound Example 3-1
-4,4'-diamine 4 parts by weight and the above-mentioned polyester polymer
6 parts by weight, each 80 parts by weight of tetrahydrofuran,
0.2 parts by weight of 2,6-di-t-butyl-4-methylphenol was added and dissolved. Using this solution, coating was performed and drying was performed at 120 C for 40 minutes to form a charge transport layer having a thickness of 25 μm, thereby producing an electrophotographic photosensitive member having three layers.

The obtained electrophotographic photosensitive member was mounted on a printer having a contact charging system (PC-PR1000 / 4R manufactured by NEC Corporation) to perform a printing operation. At that time, the residual potential and the image quality of the photoconductor, and the abrasion of the photoconductive layer after performing a print test of 50,000 sheets were evaluated. Furthermore, the image quality after that was examined.
Table 14 shows the obtained results.

Example 2 The binder resin of the charge transport layer was a polyester polymer synthesized according to the synthesis example, and the acid components were 70 mol% of dimethyl 2,6-naphthalenedicarboxylate and 30 mol% of dimethyl terephthalate. And the diol component is Compound No. 2-
An electrophotographic photoreceptor having three layers was prepared in the same manner as in Example 1 except that a polyester polymer comprising 70 mol% of diol and 30 mol% of ethylene glycol was used, and evaluated in the same manner as in Example 1. . Table 14 shows the results.

Example 3 The binder resin for the charge transport layer was a polyester polymer synthesized according to the synthesis example, and the acid components were 70 mol% of dimethyl 2,6-naphthalenedicarboxylate and 30 mol% of dimethyl terephthalate. As the diol component, compound number 1-
A three-layer electrophotographic photoreceptor was prepared in the same manner as in Example 1 except that a polyester polymer comprising 30 mol% of the diol of No. 1, 30 mol% of the diol of Compound No. 2-1 and 30 mol% of ethylene glycol was used. Then, the same evaluation as in Example 1 was performed. Table 14 shows the results.

Example 4 The binder resin of the charge transport layer is a polyester polymer synthesized according to the synthesis example, and the acid component is dimethyl 2,6-naphthalenedicarboxylate 100 mol%, and the diol component is compound No. An electrophotographic photoreceptor having three layers was prepared in the same manner as in Example 1 except that a polyester polymer comprising 70 mol% of 1-1 diol and 30 mol% of ethylene glycol was used. Did. Table 14 shows the results.

Example 5 An undercoat layer and a charge generation layer were formed on a substrate obtained in the same manner as in Example 1 in the same manner as in Example 1, and the charge transporting material was changed to a benzidine-based compound represented by Chemical Formula 7. A charge transport layer was formed in the same manner as in Example 1 except that the compound was changed, and an electrophotographic photosensitive member having three layers was prepared. The same evaluation as in Example 1 was performed.

Comparative Example 1 An undercoat layer and a charge generation layer were formed on a substrate obtained in the same manner as in Example 1 in the same manner as in Example 1, and were used as acid components of a binder resin in the charge transport layer. A charge transport layer was formed in the same manner as in Example 1 except that dimethyl terephthalate was used, to prepare an electrophotographic photosensitive member having three layers.

The obtained electrophotographic photosensitive member was mounted on a printer having a contact charging system (PC-PR1000 / 4R manufactured by NEC Corporation) to perform a printing operation. At that time, the residual potential and the image quality of the photoconductor were evaluated. After performing a print test of 50,000 sheets, the abrasion of the photosensitive layer was evaluated. Furthermore, the image quality after that was examined. Table 14 shows the obtained results.

Comparative Example 2 An undercoat layer and a charge generation layer were formed on a substrate obtained in the same manner as in Example 1 by the same method as in Example 1, and the binder resin in the charge transport layer was changed to a polycarbonate resin. A charge transport layer was formed in the same manner as in Example 1 except that the electrophotographic photosensitive member was changed to a three-layer electrophotographic photosensitive member, and evaluated in the same manner as in Comparative Example 1. Table 14 shows the obtained results.

[Table 14]

The photoreceptor obtained by combining the polyester polymer shown in the examples and the charge transporting material belonging to the general formula 3 is a printer having a contact charging device. Even when a print test is performed, abnormal image quality caused by leak discharge of the photoreceptor is obtained. Was not seen. In addition, the photoreceptor was hardly abraded, and stable electrical characteristics were obtained without lowering the chargeability of the photoreceptor and increasing the residual potential. In addition, when a charge transporting material that does not belong to the general formula 3 was used, relatively stable electric characteristics were obtained in terms of chargeability and residual potential, although the abrasion resistance and image quality were inferior.

The photoreceptors of the constitutions other than the present invention shown in the comparative examples showed large abrasion, increased dark decay and reduced chargeability, and fogging was observed in low density portions. There was a current leak from the contact charging device in a portion where the film thickness was reduced due to abrasion, and it was necessary to repair the leaked portion with an insulating material before running. This part became an image quality defect.

Examples 6 to 9 Polyvinyl butyral resin (S-LEC BM-S manufactured by Sekisui Chemical)
16 parts by weight and 550 parts by weight of cyclohexanone were mixed and stirred. Further, 8 parts by weight of a resole type phenol resin (Phenolite J-325 manufactured by Dainippon Ink and Chemicals, Inc.) was added and stirred. Further, 60 parts by weight of a titanium oxide pigment was added to this solution, and the mixture was dispersed for 5 hours by a sand grind mill. This mill base is coated with a ring coating device on a 84 mmφ aluminum substrate which has been roughened to a center line average roughness Ra = 0.18 μm by liquid honing using this coating solution, and is subjected to coating at 170 ° C. for 1 hour. Was performed to form an undercoat layer having a thickness of 4 μm.

9.5 °, 11.7 °, 15.0
°, 24.1 °, 15 parts by weight of titanyl phthalocyanine having a clear X-ray diffraction peak at the position of 27.3 °, polyvinyl butyral resin (Sekisui Chemical Esrec BM-S) 10 parts by weight,
A mixture consisting of 300 parts by weight of n-butyl alcohol was dispersed in a sand grind mill for 4 hours. This liquid was applied on the undercoat layer and dried to form a 0.2 μm-thick charge generation layer. Next, the charge transporting materials N, N-
Bis (3,4-dimethylphenyl) biphenyl-4-amine (4 parts by weight) and Examples 6 to 9 (6 parts by weight) of the polyester polymer corresponding to Examples 1 to 4 were combined with chlorobenzene 80
A part by weight was added and dissolved. Using this solution, a charge transporting layer having a thickness of 27 μm was formed by coating and drying to prepare an electrophotographic photosensitive member having three layers.

The obtained electrophotographic photosensitive member was transferred to a color copier having an intermediate transfer drum system, Acolor manufactured by Fuji Xerox Co., Ltd.
The print operation was performed by adjusting the amount of light with the -635 attached. Table 15 shows the results obtained with respect to the image quality of the photoconductor at that time.

Example 10 An undercoat layer and a charge generation layer were formed in the same manner as in Example 6 on a substrate obtained in the same manner as in Example 6, and the charge transport material in the charge transport layer was represented by the following chemical formula 8. A charge transport layer was formed in the same manner as in Example 6, except that the triarylamine-based compound shown was used, to prepare an electrophotographic photoreceptor having three layers.

The obtained electrophotographic photosensitive member was transferred to a color copier having an intermediate transfer drum system, Acolor manufactured by Fuji Xerox Co., Ltd.
The print operation was performed by adjusting the amount of light with the -635 attached. Table 15 shows the results obtained with respect to the image quality of the photoconductor at that time.

Comparative Example 3 An undercoat layer and a charge generation layer were formed on a substrate obtained in the same manner as in Example 6 by the same method as in Example 6, and the binder resin in the charge transport layer was compared with Comparative Example 1. A charge transport layer was formed in the same manner as in Example 6, except that the resin used in was changed to
An electrophotographic photosensitive member having three layers was prepared.

The obtained electrophotographic photosensitive member was transferred to a color copier having an intermediate transfer drum system, Acolor manufactured by Fuji Xerox Co., Ltd.
The print operation was performed by adjusting the amount of light with the -635 attached. Table 15 shows the results obtained with respect to the image quality of the photoconductor at that time.

Comparative Example 4 An undercoat layer and a charge generation layer were formed on a substrate obtained in the same manner as in Example 6 by the same method as in Example 6, and the binder resin in the charge transport layer was changed to a polycarbonate resin. A charge transport layer was formed in the same manner as in Example 6 except that the electrophotographic photoreceptor was composed of three layers.

The obtained electrophotographic photoreceptor was used as a color copier having an intermediate transfer drum system, Acolor manufactured by Fuji Xerox Co., Ltd.
The print operation was performed by adjusting the amount of light with the -635 attached. Table 15 shows the results obtained with respect to the image quality of the photoconductor at that time.

[Table 15]

The photoreceptor obtained by combining the polyester polymer shown in the Examples with the charge transporting substance belonging to the general formula 4 did not cause fogging and generated few black spots, and provided good image quality. When a charge transporting material that does not belong to the general formula 4 is used, although the fog slightly occurs, the increase in the number of black spots is relatively small.

The photoreceptors of the constitutions other than the present invention shown in the comparative examples suffered from fogging, more black spots, and abnormal image quality.

Examples 11 to 14 10 parts by weight of a polyamide resin and 150 parts of methyl alcohol were placed on a conductive support (Metal Me, manufactured by Toray Industries, Ltd.) on which a film of aluminum was provided on the surface of a polyethylene terephthalate film.
A coating liquid consisting of 40 parts by weight of water and 40 parts by weight of water was applied and dried to form an undercoat layer having a thickness of 1 μm. 7.5 °, 9.9
°, 12.5 °, 16.3 °, 18.6 °, 25.1 °, 2 parts by weight of hydroxygallium phthalocyanine having a diffraction peak at 28.1 °, polyvinyl butyral resin (Sekisui Chemical Eslec BM-1) 2 parts by weight, n-butyl alcohol The mixture consisting of 30 parts by weight was taken in a ball mill pot, milled for 60 hours using 1/8 inch SUS balls as a mill member, and then further diluted with 30 parts by weight of n-butyl alcohol and stirred and stirred. The composition was applied on the undercoat layer and dried to form a charge generation layer having a thickness of 0.3 μm. Next, N, N′-diphenyl-N, N′-bis (3-methylphenyl)-[1,1′-biphenyl] -4,4′-diamine shown in Compound Example 3-1 was used in an amount of 4 parts by weight. Examples 9 to 12 correspond to Examples 1 to 4, respectively, and 6 parts by weight of the polyester polymer was added to 55 parts by weight of methylene chloride, dissolved and coated and dried to form a 25 μm-thick charge transport layer. Was produced.

The photosensitive layer coating film of the electrophotographic photosensitive member produced as described above was peeled off from the conductive substrate, and a bending repetition test was performed up to 5000 times using a bending strength tester. Also, the electrophotographic photosensitive member is processed into a belt shape,
Fuji Xerox copier with belt rotation drive
A copy run test was performed on the Vivace 800 up to 100,000 cycles. Table 16 shows the results.

Example 15 Example 11 was repeated except that a benzidine-based compound represented by the chemical formula 7 was used as the charge transporting material of the charge transporting layer.
An electrophotographic photoreceptor was prepared in the same manner as in the above method, and the same evaluation was performed. Table 16 shows the results.

Comparative Example 5 An electrophotographic photosensitive member was prepared by performing the same treatment as in Example 11 except that the resin used in Comparative Example 1 was used as the binder resin for the charge transport layer. An evaluation was performed. Table 16 shows the results.

Comparative Example 6 An electron treatment was performed in the same manner as in Example 11 except that a polycarbonate resin and a benzidine-based compound represented by the chemical formula 7 were used as the binder resin and the charge transport material of the charge transport layer, respectively. A photoreceptor was prepared and evaluated in the same manner. Table 16 shows the results.

[Table 16]

The photoreceptor obtained by combining the polyester polymer shown in the examples and the charge transporting substance belonging to the general formula 3 did not break even after the bending test, and good image quality was obtained even after the copy running test. In addition, when a charge transport material that does not belong to the general formula 3 is used, it breaks during the bending test,
The durability is higher than the comparative example.

The photoreceptor having a structure other than that of the present invention shown in the comparative example broke during the bending test, and generated many white spot failures due to cracks after the copy running test.

[0115]

According to the present invention, a diol group containing a diol represented by the general formula 1 and / or a diol represented by the general formula 2 and 2,6-naphthalenedicarboxylic acid or an ester thereof are used as the binder resin for the photosensitive layer. A polyester polymer which is polymerized from a dicarboxylic acid containing a forming derivative or an ester forming derivative thereof is preferably used, and a benzidine compound represented by the general formula 3 and / or a triaryl represented by the general formula 4 are preferably used as a charge transporting agent. As a result of using the compound in combination with the amine compound, the formed coating film has high abrasion resistance and bending strength, and has excellent electrical characteristics and image quality even when used repeatedly.

Therefore, the electrophotographic photoreceptor of the present invention can be used in high-speed copying machines, and has high durability without causing problems such as cracks in the photosensitive layer even in the form of a belt. I have. As described above, by using the electrophotographic photoreceptor of the present invention, high-speed and high-stability image quality can be obtained for a long period of time.

[Brief description of the drawings]

FIG. 1 is an enlarged schematic cross-sectional view showing an example of a photoconductor having a function-separated laminated structure.

FIG. 2 is an enlarged schematic sectional view showing an example of a photoconductor having a function-separated laminated structure provided with an undercoat layer.

FIG. 3 is an enlarged schematic sectional view showing an example of a photoconductor having a function-separated laminated structure provided with a protective layer.

FIG. 4 is an enlarged schematic sectional view showing an example of a photoconductor having a function-separated laminated structure provided with an undercoat layer and a protective layer.

FIG. 5 is an enlarged schematic sectional view showing an example of a photoconductor having a single-layer structure.

FIG. 6 is an enlarged schematic sectional view showing an example of a photoconductor having a single-layer structure provided with an undercoat layer.

FIG. 7 is an enlarged schematic cross-sectional view showing an example of a photoconductor having a single-layer structure provided with an undercoat layer and a protective layer.

FIG. 8 is a schematic sectional view of an electrophotographic apparatus according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Charge generation layer 2 Charge transport layer 3 Conductive support 4 Undercoat layer 5 Protective layer 6 Photosensitive layer 7 Photoconductor 8 Charging member 9 Power supply 10 Image input device 11 Developing device 12 Transfer device 13 Cleaning device 14 Static eliminator 15 Fixing apparatus

 ──────────────────────────────────────────────────の Continued on the front page (72) Inventor Masahiko Miyamoto 1600 Takematsu, Minamiashigara-shi, Kanagawa Prefecture Inside Fuji Xerox Co., Ltd.

Claims (8)

[Claims] 1. An electrophotographic photoreceptor comprising a photosensitive layer provided on a conductive support, wherein the photosensitive layer is represented by the following general formula 1 as a binder resin and / or a general formula 2 as a binder resin. An electrophotographic photoreceptor comprising a polyester polymer polymerized from a diol group containing a diol and a dicarboxylic acid group containing 2,6-naphthalenedicarboxylic acid or an ester-forming derivative thereof. General formula 1: R ₁ is an alkylene group having 1 to 4 carbon atoms, R ₂ and R ₃ are each independently, hydrogen or an alkyl group having 1 to 7 carbon atoms, an aryl group, R _{4 to} R ₇ are each independently, hydrogen or Represents an alkyl group, cycloalkane group, or aryl group having 1 to 7 carbon atoms. General formula 2: R ₈ is an alkylene group having 1 to 4 carbon atoms, R ₉ is a direct bond or an alkylene group having 1 to 7 carbon atoms, R _{10 to} R ₁₄ are each independently, hydrogen or an alkyl group having 1 to 7 carbon atoms, cyclo An alkane group, an aryl group, and m represent a natural number of 1 to 9. 2. A method according to claim 1, wherein said photosensitive layer is a charge-transporting agent.
The electrophotographic photoreceptor according to claim 1, further comprising a triarylamine compound represented by the formula: General formula 3: R ₁ and R ₂ may be the same or different and include a hydrogen atom,
Represents an alkyl group, an alkoxy group, or a halogen atom;
R6 may be the same or different and represents a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom or a substituted amino group. K to n each represent an integer of 1 or 2. General formula 4: R _{1 to} R ₂ may be the same or different and represent a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom, m and n
Represents an integer of 1 or 2, respectively. R ₃ represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or an aryl group having 6 to 12 carbon atoms. 3. The diol represented by the general formula 1 is particularly represented by the following structural formula 5.
2. The electrophotographic photoreceptor of claim 1. Structural formula 5: 4. The diol represented by the general formula 2 is particularly represented by the following structural formula 6.
The electrophotographic photosensitive member according to any one of the above. Structural formula 6: 5. A chlorinated compound having diffraction peaks at least at positions of 7.4 °, 16.6 °, 25.5 ° and 28.3 ° in a Bragg angle (2θ ± 0.2 °) of an X-ray diffraction spectrum using Cukα ray as a charge generating material. 5. The photosensitive layer according to claim 1, wherein said photosensitive layer contains gallium phthalocyanine.
The electrophotographic photosensitive member according to any one of the above. 6. At least 7.5 °, 9.9 °, 12.5 °, 16.3 °, 18.6 in a Bragg angle (2θ ± 0.2 °) of an X-ray diffraction spectrum using Cukα ray as a charge generating material.
The electrophotographic photoreceptor according to any one of claims 1 to 4, wherein the photosensitive layer contains hydroxygallium phthalocyanine having diffraction peaks at positions of °, 25.1 °, and 28.1 °. 7. A Bragg angle (2θ ± 0.2 °) of an X-ray diffraction spectrum using Cukα ray as a charge generating material, at least 9.5 °, 11.7 °, 15.0 °, 24.1 °, 24.1 °
5. The electrophotographic photoreceptor according to claim 1, wherein the photosensitive layer contains titanyl phthalocyanine having a diffraction peak at a position of 7.3 °. 8. An electrophotographic apparatus provided with a contact-type charging device, wherein the electrophotographic photoreceptor according to claim 1 is used.