JPH0713363A - Electrophotographic photoreceptor and manufacture thereof - Google Patents

Abstract

PURPOSE:To provide the photosensitive body which possesses high sensitivity, excellent printing durability, and high abrasion resistance, and high durablity free from the generation of crack, etc., and has the less deterioration of image quality in the actual photographing and the less sensitivity reduction, and can be manufactured by using the organic solvent free from the dangerousness of the environmental damage and explosiveness, and possesses the excellent pot life (preservation performance) of the photosensitive layer paint. CONSTITUTION:As for the electrophotographic photosensitive body having a photosensitive layer on an electric conductive substrate, the binder resin in the photosensitive layer contains the polycarbonate polymer having the repetitive structure unit represented by the formula or the copolymer thereof. In the formula, each of R1-R8 is a hydrogen atom, halogen atom, substituted or nonsubstituted alkyl group having the number of carbon atoms of 1-10, cycloalkyl group, and an aryl group, and at least one between R9 and is the straight chain alkyl group having the number of carbon atoms of 8-30.

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 a method for producing the same.

[0002]

2. Description of the Related Art Conventionally, in a Carlson method electrophotographic copying machine, after uniformly charging a photoreceptor, the charge is erased imagewise by exposure to form an electrostatic latent image. The image is developed and visualized with toner, and then the toner is transferred and fixed on paper or the like.

On the other hand, the surface of the photoconductor is cleaned by removing adhered toner and removing static electricity, and is repeatedly used for a long period of time.

Therefore, as an electrophotographic photoreceptor, not only the electrophotographic characteristics such as excellent charging characteristics and sensitivity but also small dark decay, but also physical properties such as printing durability, abrasion resistance and scratch resistance upon repeated use. Also, it is required to have good resistance to ozone generated during corona discharge and ultraviolet rays during exposure.

Conventionally, selenium has been used as an electrophotographic photoreceptor.
Inorganic photoconductors having an inorganic photoconductive substance such as zinc oxide and cadmium sulfide as a main component of a photosensitive layer have been widely used. However, since these inorganic photoconductors are harmful to the human body, there is a problem in their disposal.

In recent years, an organic photoconductor using a non-polluting organic substance has been actively developed and put into practical use. For example,
Japanese Examined Patent Publication (Kokoku) No. 50-10496 describes an organic photoreceptor having a photosensitive layer containing poly-N-vinylcarbazole and 2,4,7-trinitro-9-fluorene. But,
These photoreceptors are not satisfactory in sensitivity and durability.

Further, a function-separated type photoconductor is promising in which different substances are assigned the charge generating function and the charge transporting function, and a substance exhibiting each function can be selected from a wide range according to desired characteristics.

However, such an organic photoconductor is generally inferior in mechanical strength to an inorganic photoconductor, and there is a problem that a cleaning blade, a developing brush or the like is rubbed or abraded by mechanical external force. These cause deterioration of the output image, and a stable and clear image cannot always be obtained.

The above problems are largely due to the characteristics of the binder resin contained in the outermost layer of the photoreceptor.

In recent years, various researches and developments have been carried out, and a laminated type photoconductor in which the functions of charge generation and charge transport are shared by the respective layers has been proposed. Conventionally, such a laminated organic photoreceptor is mainly used for negative charging, and has a structure in which a thin charge generation layer is provided on a conductive support and a relatively thick charge transport layer is provided thereon.

As a binder used in such a photoreceptor, it is well known that a bisphenol A type polycarbonate resin exhibits good characteristics in terms of charging characteristics, sensitivity, residual potential and repetitive characteristics. There is.

However, as a result of investigations by the present inventors,
Since the bisphenol A type polycarbonate resin has a high polymer crystallinity, its solution easily causes gelation,
It has a drawback that it cannot be used in about 1 to 2 days.
Further, when a film is formed by coating, crystalline polycarbonate is likely to be deposited on the surface of the film at the time of forming the coating film, and a convex portion is likely to be formed,
For this reason, the coating film is trailed to lower the yield, or toner is attached to the convex portions and remains uncleaned when used as a photoconductor, and image defects due to so-called cleaning failure are likely to occur.

When the electrophotographic photosensitive member using the bisphenol A type polycarbonate resin as a binder is used as a photosensitive member of an electrophotographic copying machine, the surface of the photosensitive layer is scratched by being rubbed with a magnetic brush or a cleaning blade. It has the drawback that the photosensitive layer is gradually worn away.

In order to improve these drawbacks, attempts have been made to replace the surface layer portion of the photosensitive layer with a binder resin structure having high abrasion resistance, as described in JP-A-1-118137.

On the other hand, since the high image quality and the good copying workability depend on the uniformity of the film thickness and the surface uniformity of the photoconductor, the coating composition for forming the photoconductor constituting layer or the coating
Defects in the film surface such as citrus peel, pinholes, coating streaks, and cracks (solvent cracks) caused by drying are serious problems in terms of copying characteristics and production technology.

In response to the above-mentioned problems, introduction of a substituent having a fluorine atom on the carbon between the phenylene rings of bisphenol type polycarbonate (Japanese Patent Laid-Open No. 63-65444), substitution of an alkyl group or a halogen atom on the phenylene ring. (JP 63-1
48263), or a copolymer of monomers in which both phenylene rings are substituted with a phenyl group or a cyclohexyl group (JP
No. 1-269942, No. 1-269943), etc. have been proposed, but they do not have sufficient surface strength and surface smoothness, are vulnerable to abrasion and scratches, and deteriorate in image quality during repeated use. There are problems such as sensitivity deterioration due to wear reduction.

For the purpose of improving these characteristics, there are techniques described in, for example, JP-A-64-13061, JP-A-4-230767, and JP-A-4-320420. This is intended to make the binder resin also have a charge transporting property.
However, none of them have obtained sufficient performance.

On the other hand, conventional polycarbonates which are often used as binders for photosensitive layers have often used halogenated hydrocarbons such as methylene chloride, 1,2-dichloroethane, chloroform and monochlorobenzene, which have high solubility, as solvents. It was

On the other hand, in recent years, voices concerning environmental protection have been increasing, and regulations on harmful substances and substances polluting the environment have been strengthened. Under such circumstances, the above-mentioned halogenated hydrocarbons may not be used in the future, or the amount thereof may be limited.

Therefore, the binder resin for the photosensitive layer includes hydrocarbons such as toluene and benzene, ketones such as acetone, methyl ethyl ketone and cyclohexanone, esters such as ethyl acetate and butyl acetate, alcohols such as methanol, ethanol and butanol. Those having high solubility in ethers, ethers such as tetrahydrofuran, 1,4-dioxane, furan and furfural, acetals and the like are preferable.

Suitable resins for the undercoat layer and the charge generation layer have been found and have already been put to practical use.

However, when a resin other than the polycarbonate resin which is soluble in the above-mentioned solvent is used as the binder resin for the charge transport layer, the electrophotographic characteristics such as low sensitivity and increase in residual potential due to repeated use, and There is a problem in mechanical durability such as abrasion during repeated use, deterioration in image quality due to scratches, and deterioration in sensitivity due to film abrasion, and no resin satisfying these has been found.

[0023]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a photoreceptor having high sensitivity, high printing durability and abrasion resistance, high durability without cracks, and little deterioration in image quality during actual copying and sensitivity deterioration. Another object of the present invention is to provide a photoconductor that can be produced using an organic solvent that does not cause environmental damage or explosiveness, and that has good pot life (preservation) of the photosensitive layer coating material. .

[0024]

The object of the present invention is to provide an electrophotographic photoreceptor having a photosensitive layer provided on a conductive substrate, wherein the binder resin of the photosensitive layer is represented by the following general formula [I]. The present invention is achieved by an electrophotographic photoreceptor and a production method, which comprises a polycarbonate polymer having a repeating structural unit or a copolymer thereof.

[0025]

[Chemical 3]

[Wherein, R _{1 to} R ₈ represent three groups of a hydrogen atom, a halogen atom or a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a cycloalkyl group and an aryl group,
At least one of R ₉ and R ₁₀ represents a straight-chain alkyl having 8 to 30 carbon atoms. ] It is important to use a linear alkyl group having 8 to 30 carbon atoms for at least one of R ₉ and R ₁₀ .

The closer the number of carbons is to 30, the greater the elastomeric or rubbery properties, but the other advantageous properties of polycarbonate, such as the electrical properties, are largely unchanged.

Conventionally, a polycarbonate having a high hardness has been required in order to improve printing durability, but it has been found that a binder having elastomeric properties such as the polycarbonate of the present invention can be effectively used.

Due to its elastomeric properties, it has a large residual stress relaxation force and is useful for cracking. Further, since the molecular chains tend to be irregular, the coating liquid does not become cloudy.

Specific examples of R _{1 to} R _{8 in} the general formula [I] are hydrogen atom, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, 1-methylpropyl group, 2-methylpropyl group, t-butyl group, n-pentyl group,
Isopentyl group, n-hexyl group, isohexyl group, phenyl group, tolyl group, xylyl group, trimethylphenyl group, ethylphenyl group, cyclopentyl group, cyclohexyl group, cyclooctyl group, fluorine atom, chlorine atom, bromine atom, etc. You can

R _{1 to} R ₈ may be the same groups as each other,
Alternatively, it may be a different group.

R ₉ or R _{10 in the} above general formula [I]
Specific examples of are hydrogen atom, methyl group, ethyl group, n-
There are propyl group, isopropyl group, n-butyl group, 1-methylpropyl group, 2-methylpropyl group, t-butyl group, n-pentyl group, isopentyl group, n-hexyl group and has 8 carbon atoms.
These include octyl, nonyl, undecyl, dodecyl, pentadecyl, hexadecyl, heptadecyl,
Examples include octadecyl, eicosyl, tetracosyl, pentacosyl, hexacosyl, heptacosyl, octacosyl, nonacosyl and the like.

The polycarbonate composed of the repeating unit represented by the above general formula [I] is represented by, for example, one kind or two or more kinds of the following general formulas.

Dihydric phenols (A)

[0035]

[Chemical 4]

And a carbonate precursor such as phosgene by condensation polymerization in the presence of a suitable acid binder in a suitable neutral polar solvent, or by transesterification of the dihydric phenol (A) with the bisaryl carbonate. Can be obtained by

As the acid binder, various kinds such as known ones can be used, and specifically, for example, alkali metal hydroxides such as sodium hydroxide and potassium hydroxide, organic bases such as pyridine and the like. A mixture or the like is used.

As the solvent, for example, methylene chloride, chlorobenzene, xylene, etc. are used. Furthermore,
A catalyst such as a tertiary amine or a quaternary ammonium salt such as triethylamine is used to accelerate the polycondensation reaction, and a molecular weight regulator such as pt-butylphenol or phenylphenol is used to adjust the degree of polymerization. It is desirable to add and carry out the reaction. If desired, a small amount of an antioxidant such as sodium sulfite and hydrosulfide may be added. The reaction is usually carried out at a temperature in the range of 0 to 150 ° C, preferably 5 to 40 ° C. The reaction time depends on the reaction temperature, but is usually 0.5 minutes to 10 hours, preferably 1 minute to 2 hours. During the reaction, p of the reaction system
It is desirable to keep H at 10 or more.

On the other hand, in the latter transesterification method,
The dihydric phenol compound and bisaryl carbonate are mixed and reacted at high temperature under reduced pressure. The reaction is usually carried out at a temperature in the range of 150 to 350 ° C, preferably 200 to 300 ° C, and the degree of reduced pressure is finally set to preferably 1 mmHg or less, and phenols derived from the bisaryl carbonate produced by the transesterification reaction. Is removed from the system. Although the reaction time depends on the reaction temperature and the degree of reduced pressure, it is usually about 1 to 4 hours. The reaction is preferably carried out in an atmosphere of an inert gas such as nitrogen or argon, and the reaction may be carried out by adding the above-mentioned molecular weight modifier, antioxidant or the like, if desired.

The dihydric phenol (A) used in the present invention is a catalyst, preferably an acid catalyst, for the co-reaction of the following specific aldehyde compound or ketone compound (B) with phenol compounds (C) and (D). Manufactured in the presence of.

[0041]

[Chemical 5]

Specifically, 1 mol of the ketone or aldehyde compound of (B) and 1 mol of the phenol compound (C) and 1 mol of the phenol compound (D) are used as an acid catalyst, for example, hydrochloric acid, hydrobromic acid, sulfuric acid, In the presence of methane sulfonic acid, trifluoromethane sulfonic acid, benzene sulfonic acid, toluene sulfonic acid, polyphosphoric acid and ion exchange resin acids such as polystyrene sulfonic acid, a co-reaction between aldehyde and phenol occurs to give a new divalent phenol. The reaction is carried out under temperature-pressure conditions such that it forms. In general, the reaction proceeds very satisfactorily at 1 atmosphere and room temperature. The amount of the acid catalyst used is a catalytic amount. Here, the catalytic amount means an effective amount that catalyzes the reaction between an aldehyde that produces a dihydric phenol and the phenol. Usually this catalyst amount is about 0.1-
It is in the range of about 10% by weight acid.

The phenols of (C) and (D) may be the same. In that case, 1 mol of the aldehyde or ketone of (B) is reacted with 2 mol of phenol.

It is often advantageous to use an excess of the phenolic reactant and to recover or remove unreacted phenol at the end of the reaction.

As another polycarbonate copolymer used in the present invention, the above general formula [I] and the following general formula [I
I] includes a repeating structural unit.

[0046]

[Chemical 6]

[Wherein R _{11 to} R ₁₈ are hydrogen atoms, halogen atoms, substituted or unsubstituted alkyl groups having 1 to 10 carbon atoms,
Cycloalkyl group, aryl group. A represents a linear, branched, or cyclic alkylidene group having 1 to 10 carbon atoms, an aryl-substituted alkylidene group, a sulfonyl group, a sulfide group, or an ether group, or may be directly bonded without A. The polycarbonate copolymer containing the repeating unit represented by the general formula [I] is one or more dihydric phenols (A) and one or more dihydric phenols (E) shown below. And a carbonate precursor such as phosgene and the like in the presence of a suitable acid binder in a suitable solvent for bond polymerization, or these dihydric phenols (A), dihydric phenols (E) and bisaryl carbonates. It can be obtained by a method such as transesterification reaction.

[0048]

[Chemical 7]

Specific examples of the polycarbonate having a repeating unit represented by the above general formula [II] include JP-A-50-9.
8332, 60-172045, 61-62040, JP 1-269942, 1
-269943, 1-273046, 4-268365.

The polycarbonate of the present invention may be a homopolymer consisting of one type of repeating unit represented by the above general formula [I], or it may be composed of two or more types of the general formula [I] in an arbitrary ratio. It may be a copolymer. These may be used alone or in combination of two or more in an arbitrary ratio as a mixture or the like.

The polycarbonate of the present invention has a weight average molecular weight of usually 5,000 to 300,000, preferably 20,000 to 200,00.
0 is good.

Another polycarbonate copolymer according to the present invention comprises one or more kinds of repeating units represented by the general formula [I] and one or more kinds of the general formula [II]. And the repeating unit represented. The ratio of the repeating units [I] and [II] is
At least [I] is preferably 20 mol%, more preferably 30 mol% or more.

These polycarbonate copolymers may be used alone or in a combination of two or more at an arbitrary ratio as a mixture or the like.

Further, the polycarbonate or polycarbonate copolymer of the present invention can be used as a mixture with other known binder resins such as other known polycarbonates as long as the object of the present invention is not impaired. In this case, the content of the polycarbonate or the polycarbonate copolymer of the present invention is 30% by weight or more, preferably 50% by weight or more.

Next, specific examples of the compound of the polycarbonate binder resin of the present invention are as follows.

A. As a homopolymer

[0057]

[Chemical 8]

[0058]

[Chemical 9]

B. As a copolymer

[0060]

[Chemical 10]

[0061]

[Chemical 11]

As the binder which may be used in combination with the carbonate resin used as the binder,
For example, the following can be mentioned.

(1) Polyester (2) Methacrylic resin (3) Acrylic resin (4) Polyvinyl chloride (5) Polyvinylidene chloride (6) Polystyrene (7) Polyvinyl acetate (8) Styrene copolymer resin (for example, styrene- Butadiene copolymer, styrene-methyl methacrylate copolymer, etc.) (9) Acrylonitrile copolymer resin (for example, vinylidene chloride-acrytronitrile copolymer, etc.) (10) Vinyl chloride-vinyl acetate copolymer Combined (11) Vinyl chloride-vinyl acetate-maleic anhydride copolymer (12) Silicone resin (13) Silicone-alkyd resin (14) Phenolic resin (for example, phenol-formaldehyde resin, cresol-formaldehyde resin,
Etc.) (15) Styrene-alkyd resin (16) Poly-N-vinylcarbazole (17) Polyvinyl butyral (18) Polyvinyl formal (19) Polyhydroxystyrene

[0064]

Next, the charge generating substance (CGM) and the carrier transporting substance (CTM) used as the organic photo-semiconductive substance will be described.

If the charge generating substance used in the present invention absorbs electromagnetic waves and generates free carriers,
Both inorganic pigments and organic pigments can be used. For example, inorganic pigments such as amorphous selenium, cadmium sulfide and zinc oxide, or (1) azo pigments such as monoazo pigments, polyazo pigments, metal complex salts, azo pigments, pyrazolone azo pigments, stilbene azo and thiazole pigments (2) perylene -Based pigments (3) Anthraquinone-based or polycyclic quinone-based pigments (4) Indigoid-based pigments (5) Phthalocyanine-based pigments such as metal phthalocyanine and metal-free phthalocyanine (6) Azine pigments (7) Methine-based pigments such as cyanine pigments and azomethine pigments Pigments (8) Quinoline pigments (9) Nitro pigments and other organic pigments can be used.

In the present invention, preferable CGMs include the bisazo pigments described in JP-A No. 2-20877, the perylene derivative described below, and titanyl phthalocyanine pigments.

<Perylene and Titanyl Phthalocyanine Pigment> As the perylene pigment used in the present invention, there is
3-26384, halogen substitution type, JP-A-62-54267, asymmetric type, JP-A-54-126036, JP-A-58-152247.
No. 59-31957, JP-A No. 2-251858, 4-62560,
The perylene derivatives described in JP-A-5-6014 and the like are preferably used. More preferably, the following general formula [III] or [I
V] represented by bisindazopyridonoperylene (Bis imi
dazo pridono perylene; abbreviated as BIPP. ) Is preferably used.

[0068]

[Chemical 12]

[In the general formulas [III] and [IV], Z represents an atomic group necessary for forming a substituted or unsubstituted divalent aromatic ring. Specific examples of Z are benzene ring, naphthalene ring, anthracene ring, phenanthrene ring, pyridine ring,
Examples include a pyrimidine ring, a pyrazole ring, and an anthraquinone ring. Of these, a benzene ring and a naphthalene ring are preferable, and a benzene ring is particularly preferable. Z
May or may not have a substituent, but an unsubstituted one is particularly preferable.

As the substituent of Z, alkyl, alkoxy, aryl, aryloxy, acyl, acyloxy,
Amino, carbamoyl, halogen, nitro, cyano and the like can be mentioned, but an alkyl group is preferable.

Specific examples of the compounds represented by the general formulas [III] and [IV] are shown below.

[0072]

[Chemical 13]

[0073]

[Chemical 14]

Next, the titanyl phthalocyanine used in the present invention is the X-ray for Cu-Kα ray (wavelength 1.541Å).
In the line diffraction spectrum, the peak position at the Bragg angle 2θ including the measurement error of ± 0.2 ° (±
Although the error value of 0.2 ° is omitted), the following ones are preferably used.

(1) 7.5 as described in JP-A-61-239248
Α-type titanyl phthalocyanine having strong peaks at °, 12.3 °, 16.3 °, 25.3 ° and 28.7 °, (2) 9.3 °, 10.6 °, as described in JP-A-62-67094 and JP-A-63-218768 13.2 °, 15.1 °, 15.7 °, 16.1
Β-type titanyl phthalocyanine with strong peaks at °, 20.8 °, 23.3 °, 26.3 ° and 27.1 ° (3) Strong peak at 23.4 ° as reported in Journal of Electrophotography, Vol. 27, No. 4, p. M-type titanyl phthalocyanine having (4) 9.2 °, 11.6 °, 13. as described in JP-A-2-309362.
Examples thereof include I-type titanyl phthalocyanine having strong peaks at 0 °, 24.1 °, 26.2 ° and 27.2 °.

More preferably, JP-A-64-17066 and JP-A-
As in 3-200790, titanyl phthalocyanine having strong peaks at 9.6 ° and 27.2 ° (in the present invention, referred to as Y-type titanyl phthalocyanine and discriminated from the former four types) is used.

The peak of titanyl phthalocyanine according to the present invention is a cone-shaped protrusion having an acute angle which is clearly different from noise.

The basic structure of the titanyl phthalocyanine of the present invention is represented by the following general formula [V].

[0079]

[Chemical 15]

[Wherein X ¹ , X ² , X ³ and X ⁴ represent a hydrogen atom, a halogen atom, an alkyl group or an alkoxy group, and n, m, l and k are integers of 0 to 4] Represent The above peak was obtained from the reflection diffraction spectrum measured under the following conditions.

[Using JEOL's JDX-8200 type X-ray diffractometer] X-ray tube Cu voltage 40.0 KV current 100 mA start angle 6.00 deg stop angle 35.00 deg. Step angle 0.020 deg. Measurement time 0.50 sec The titanyl phthalocyanine according to the present invention is produced, for example, by the following production method. 1,3-Diiminoisoindoline and sulfolane are mixed, titanium tetrapropoxide is added thereto, and the mixture is reacted in a nitrogen atmosphere at 80 to 300 ° C, preferably 100 to 260 ° C. After completion of the reaction, the mixture is allowed to cool and the precipitate is collected by filtration to obtain titanyl phthalocyanine.

As a device used for the treatment, in addition to a general stirring device, a homomixer, a disperser, an agitator,
Alternatively, a ball mill, a sand mill, an attritor or the like can be used.

Among the above-mentioned titanyl phthalocyanines, those which are preferably used in the present invention are Y-type titanyl phthalocyanines, more preferably crystalline titanyl phthalocyanines having a peak intensity of 9.6 ° of 40% or more of a peak intensity of 27.2 °, Preferably in the phthalocyanine according to the present invention, based on the peak intensity of 27.2 °, titanyl phthalocyanine in the crystalline state showing a peak intensity of 9.6 ° 60% or more and peak intensity of 9.6 ° is 50% or more and 6.7 °. By containing titanyl phthalocyanine in a crystalline state having a peak intensity of about 30%,
It is possible to form a photoreceptor having high sensitivity and good charging characteristics.

FIG. 1 shows an example of the X-ray diffraction diagram of the Bragg angle 2θ of the Y-type titanyl phthalocyanine preferably used in the present invention.

In the present invention, in addition to the CGM described above, another CG
You may use M together. Examples thereof include α-type, β-type, and fumorphus-type titanyl phthalocyanines, as well as other metal-containing phthalocyanine pigments, metal-free phthalocyanines, azo pigments, anitraquinone pigments perylene pigments, polycyclic quinones, and squarylium pigments.

<Dispersion Medium of Organic Pigment> As the dispersion medium of the organic pigment used in the present invention, for example, hydrocarbons such as hexane, benzene, toluene, xylene, methylene chloride, methylene bromide, 1,2- Dichloroethane, syn-tetrachloroethane, cis-1,2-dichloroethylene, 1,1,2-trichloroethane, 1,1,1-trichloroethane, 1,2-dichloropropane, chloroform, bromoform, chlorobenzene Halogenated hydrocarbons such as acetone, ketones such as acetone, methyl ethyl ketone and cyclohexanone, esters such as ethyl acetate and butyl acetate, methanol, ethanol, propanol, butanol, cyclohexanol, heptanol, ethylene glycol, methyl cellosolve, ethyl cellosolve, acetic acid Alcohol such as cellosolve and its derivatives, tetra Dorofuran, 1,4
Ethers such as dioxane, furan, furfural, acetals, pyridine, butylamine, diethylamine,
In addition to amines such as ethylenediamine and isopropanolamine, nitrogen compounds such as amides such as N, N-dimethylformamide, fatty acids and phenols, sulfur such as carbon disulfide and triethyl phosphate, phosphorus compounds and the like can be mentioned.

<Carrier Transport Material> Carrier transport materials (CTM) usable in combination in the present invention include:
Although not particularly limited, for example, oxazole derivatives, oxadiazole derivatives, thiazole derivatives, thiadiazole derivatives, triazole derivatives, imidazole derivatives, imidazolone derivatives, imidazolidine derivatives, bisimidazolidine derivatives, styryl compounds, hydrazone compounds,
Pyrazoline derivative, amine derivative, oxazolone derivative, benzothiazole derivative, benzimidazole derivative, quinazoline derivative, benzofuran derivative, acridine derivative, phenazine derivative, aminostilbene derivative, poly-N-vinylcarbazole, poly-1-pyralpyrene, poly-9- Such as vinyl anthracene.

The structure of a particularly representative structure is shown below.

[0089]

[Chemical 16]

[0090]

[Chemical 17]

[0091]

[Chemical 18]

[0092]

[Chemical 19]

As the CTM used in the present invention, those having an excellent ability to transport holes generated upon irradiation with light are preferable, and those suitable for combination with the organic pigment used in the present invention are preferable.

<Layer Structure> The photoconductor of the present invention has the structure shown in FIG.
And a photosensitive body comprising a laminate of a charge generation layer (CGL) 2 containing CGM as a main component and a charge transport layer (CTL) 3 containing CTM as a main component on a conductive support 1 as shown in (2). The layer 4 is provided. As shown in (3) and (4) of the same drawing, the photosensitive layer 4 is an intermediate layer 5 provided on the conductive support 1.
You may provide through. Thus, when the photosensitive layer 4 has a two-layer structure, an electrophotographic photosensitive member having the best electrophotographic characteristics can be obtained. Further, in the present invention, FIG.
And a layer 6 containing the CTM as a main component as shown in (6).
The photosensitive layer 4 in which the particulate CGM 7 is dispersed may be provided directly on the conductive support 1 or via the intermediate layer 5.

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

When the photosensitive layer 4 has a two-layer structure, C
Which of GL2 and CTL3 is to be the upper layer is determined by whether the charging polarity is positive or negative. That is, in the case of forming the negative charging type photosensitive layer, it is advantageous to use CTL3 as the upper layer, because CTM in the CTL3 is a substance having a high hole transporting ability.

Further, CGL which constitutes the photosensitive layer 4 having a two-layer structure
2 can be formed by the following method directly or on the conductive support 1 or CTL 3 provided with an intermediate layer such as an adhesive layer or a blocking layer as required.

(1) Vacuum evaporation method (2) Method of applying a solution in which a carrier generating substance (CGM) is dissolved in a suitable solvent (3) CGM needs to be made into fine particles in a dispersion medium by a ball mill, sand grinder, etc. According to the method, a dispersion liquid obtained by mixing and dispersing with a binder is applied.

Specifically, vacuum deposition, sputtering,
A vapor deposition method such as CVD or a coating method such as dipping, spraying, blade or roll method may be used.

The thickness of the CGL2 thus formed is preferably 0.01 to 5 μm, more preferably 0.05 μm.
It is 5 to 3 μm.

The thickness of CTL3 can be changed as required, but is usually preferably 5 to 40 μm.

The composition ratio in this CTL was such that 1 part by weight of the carrier transport material (CTM) of the present invention was used as a binder.
0.1 to 5 parts by weight is preferable, but fine particle CG
When the photosensitive layer in which M is dispersed is formed, it is preferable to use the binder in an amount of 5 parts by weight or less with respect to 1 part by weight of CGM.

Further, the intermediate layer functions as an adhesive layer or a blocking layer, and in addition to the binder resin described below,
For example, polyvinyl alcohol, ethyl cellulose, carboxymethyl cellulose, vinyl chloride-vinyl acetate copolymer, vinyl chloride-vinyl acetate-maleic anhydride copolymer, casein, polyamide, N-alkoxymethylated nylon, starch and the like are used.

Other binder resins usable for the protective layer and the intermediate layer include polystyrene, polyethylene, polypropylene, acrylic resin, methacrylic resin, vinyl chloride resin, vinyl acetate resin, polyvinyl butyral resin, epoxy resin, polyurethane resin, Includes two or more of addition resin such as phenol resin, polyester resin, alkyd resin, polycarbonate resin, silicone resin, melamine resin, polyaddition resin, polycondensation other resin, and repeating units of these resins. In addition to an insulating resin such as a copolymer resin such as a vinyl chloride-vinyl acetate-maleic anhydride copolymer resin, a polymer organic semiconductor such as poly-N-vinylcarbazole may be used.

In the present invention, the photosensitive layer may contain one or more electron-accepting substances for the purpose of improving sensitivity, reducing residual potential and reducing fatigue during repeated use.

Examples of the electron accepting substance which can be used here include succinic anhydride, maleic anhydride, dibromomaleic anhydride, phthalic anhydride, tetrachlorophthalic anhydride, tetrabromophthalic anhydride and 3-nitrophthalic anhydride. Acid, 4-nitrophthalic anhydride, pyromellitic dianhydride,
Mellitic anhydride, tetracyanoethylene, tetracyanoquinodimethane, o-dinitrobenzene, m-dinitrobenzene, 1,3,5-trinitrobenzene, paranitrobenzonitrile, picryl chloride, quinone chlorimide, chloranil, bulmannyl, Dichlorodicyanoparabenzoquinone, anthraquinone, dinitroanthraquinone, 2,7-dinitrofluorenone, 2,4,7-trinitrofluorenone,
2,4,5,7-Tetranitrofluorenone, 9-fluorenylidene (dicyanomethylene malonodinitrile), polynitro-9
-Fluorenylidene- (dicyanomethylene malonodinitrile), picric acid, o-nitrobenzoic acid, p-nitrobenzoic acid, 3,5-dinitrobenzoic acid, pentafluorobenzoic acid,
Examples include 5-nitrosalicylic acid, 3,5-dinitrosalicylic acid, phthalic acid, mellitic acid, and other compounds having a high electron affinity. The addition ratio of the electron-accepting substance is 100: 0.01 to 200, preferably 100: 0.1 to 100, by weight, organic pigment used in the present invention: electron-accepting substance.

In addition, organic amines can be added to the photosensitive layer of the present invention for the purpose of improving the charge generation function of CGM, and it is particularly preferable to add a secondary amine. These compounds are described in JP-A-59-218447 and JP-A-62-8160.

An antioxidant may be added to the photoreceptor of the present invention for the purpose of preventing ozone deterioration.

Typical specific examples of such an antioxidant are shown below, but the invention is not limited thereto.

Group (1): Hindered phenols Dibutylhydroxytoluene, 2,2'-methylenebis (6-t
-Butyl-4-methylphenol), 4,4'-butylidene bis
(6-t-butyl-3-methylphenol), 4,4'-thiobis (6-
t-butyl-3-methylphenol), 2,2'-butylidene bis
(6-t-butyl-4-methylphenol), α-tocophenol, β-tocophenol, 2,2,4-trimethyl-6-hydroxy-7-t-butylchroman, pentaerythryltetrakis
[3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], 1,6-hexanediol-bis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] , Butylhydroxyanisole, Dibutylhydroxyanisole,
1- [2-{(3,5-di-tert-butyl-4-hydroxyphenyl) propionyloxy} ethyl] -4- [3- (3,5-di-t-butyl-4-
Hydroxyphenyl) propionyloxy] -2,2,6,6-tetramethylpiperidyl and the like.

Group (2): Para-phenylenediamines N-phenyl-N'-isopropyl-p-phenylenediamine,
N, N′-di-sec-butyl-p-phenylenediamine, N-phenyl-N-sec-butyl-p-phenylenediamine, N, N′-dimethyl-N, N′-di-t-butyl-p -Phenylenediamine etc.

Group (3): Hydroquinones 2,5-di-t-octylhydroquinone, 2,6-didodecylhydroquinone, 2-dodecylhydroquinone, 2-dodecyl
-5-Chlorohydroquinone, 2-t-octyl-5-methylhydroquinone, 2- (2-octadecenyl) -5-methylhydroquinone, etc.

Group (4): Organophosphorus compounds Dilauryl-3,3'-thiodipropionate, distearyl-3-3'-thiodipropionate, ditetradecyl-3,
3'-thiodipropionate etc.

These compounds are known as antioxidants for rubbers, plastics, oils and fats, etc., and commercially available products can be easily obtained.

These antioxidants may be added to either CGL, CTL, or the protective layer. In that case, the amount of the antioxidant added is 0.1 to 100% by weight, preferably 1 to 50% by weight, particularly preferably 5 to 25%, based on 100% by weight of CTM.
Is the weight.

In addition, the photoreceptor of the present invention may further contain an ultraviolet absorber or the like for the purpose of protecting the photosensitive layer, if necessary, and may also contain a dye for correcting color sensitivity.

If necessary, the protective layer according to the present invention may contain less than 50% by weight of a thermoplastic resin for the purpose of improving processability and physical properties (preventing cracks, imparting flexibility, etc.).

As the electroconductive support used in the construction of the electrophotographic photosensitive member of the present invention, the following are mainly used, but the electroconductive support is not limited thereto.

1) A metal plate made of aluminum, stainless steel, nickel or the like, a metal drum 2) A thin metal layer made of aluminum, palladium, gold or the like provided on a support such as paper or a plastic film by laminating or vapor deposition 3 ) A material in which a layer of a conductive compound such as a conductive polymer, indium oxide or tin oxide is applied or vapor-deposited on a support such as paper or a plastic film.

In the present invention, as a desirable mode for producing a photosensitive member, for example, a dispersion liquid in which each of the above-mentioned CGM and CTM is dispersed in a suitable dispersion medium or solvent together with a binder resin containing at least the binder according to the present invention is applied by dip coating. , Spray coating, blade coating, roll coating, etc., on the support or the undercoat layer or CTL or CGL, and then dried.

[0121]

EXAMPLES Examples of the present invention will be specifically described below.
This does not limit the embodiments of the present invention.

Example 1 30 g of polyamide resin CM-8000 (manufactured by Toray Industries, Inc.) was placed in a mixed solvent of 900 ml of methanol and 100 ml of 1-butanol, and 50
It melted by heating at ℃. This solution was applied onto an aluminum drum substrate having an outer diameter of 80 mm by dip coating to form an intermediate layer having a thickness of 0.5 μm.

Exemplified as CGM: 2 parts by weight of BIPP (X-1);
In addition to the parts by weight, dispersion was carried out for 20 hours with a sand grinder to obtain a CGL coating liquid. This solution was applied onto an Al substrate by dip coating to form a CGL having a thickness of 0.5 μm.

15 parts by weight of Compound Example D-17 as CTM and 1,20 parts by weight of Polymer Example A-1 having a structure of the general formula [I] as a CTL binder are 1,2-dichloroethane 100 parts.
It melt | dissolved in weight part and obtained the CTL coating liquid. This coating liquid is C
It was applied by dip coating on GL and dried at 100 ° C. for 30 minutes to obtain a negatively chargeable electrophotographic photosensitive member No. 1 having a thickness of 20 μm.

Examples 2 to 14 Electrophotographic photoreceptors Nos. 2 to 14 of the present invention were obtained in the same manner as in Example 1 except that the combination of CGM, CTM and binder was changed as shown in Table 1. It was

The following compounds were used as other CGM compounds.

[0127]

[Chemical 20]

Comparative Examples 1 to 5 Polycarbonate C-1 below was used as a comparative example binder.
Alternatively, a photoconductor of a comparative example was obtained in the same manner as in Example 1 except that C-2 was used and changed as shown in Table 1. The photoconductor Nos. Are No. 15 to 19, respectively.

[0129]

[Chemical 21]

[0130]

[Table 1]

-Evaluation of Coating Liquid and Photoreceptor-Table 2 shows the results of the stability of the CGL liquid in Examples 1-14 and Comparative Examples 1-5. The rate of change in viscosity is shown by the following formula: {[Viscosity after one month (CPS) -Viscosity immediately after adjustment (CPS)] / [Viscosity immediately after adjustment (CPS)]} × 100 The smaller the value, the more stable the coating solution. Good nature. Also, the appearance of the coating liquid after standing for 1 month was visually observed.

Further, the obtained photoconductor sample was subjected to "U-BI
X4045 ”(manufactured by Konica Corporation), a 100,000-copy actual copying test was performed, and the presence or absence of image defects before and after the actual copying test, the change in surface potential, and the amount of film thickness loss were examined.

Black paper potential Vb: Surface potential for an original with a reflection density of 1.3 White paper potential Vw: Surface potential for an original with a reflection density of 0.0 Residual potential Vr: Surface potential after static elimination 100,000 copies ended for film wear due to surface friction After that, the film thickness of the photoconductor was measured and compared with the initial stage.

The results are shown below. The results are shown in Table 2.

[0135]

[Table 2]

By using the binder of the present invention,
Improvements such as coating liquid stability, repeated electrophotographic characteristics, printing durability, abrasion resistance, and crack prevention were made.

Example 20 Polyamide resin “Laccamide 5003” (manufactured by Dainippon Ink and Chemicals, Inc.) 3 parts (parts represent parts by weight; the same applies hereinafter) with methanol
It was heated to 100 parts and dissolved, and coated on an aluminum drum by a dip coating method to form an undercoat layer having a film thickness of 0.5 μm.

Then, Y-type titanyl phthalocyanine X-2
4; 3 parts, cellulose-modified silicone resin "KR5240" (manufactured by Shin-Etsu Chemical Co., Ltd.) as a binder resin, 3 parts solid content, and 100 parts of methyl isobutyl ketone as a dispersion medium dispersed in a sand mill. Was applied by a dip coating method to form a carrier generation layer having a film thickness of 0.2 μm. Next, 1.5 parts of carrier transport material D-14, IR of AO agent
GNOX1010 (manufactured by Ciba Geigy) 0.1 part, and a minute amount of silicone oil "KF-54" (manufactured by Shin-Etsu Chemical Co., Ltd.) dissolved in 10 parts of 1,2-dichloroethane. Then, after drying, a carrier transport layer having a film thickness of 25 μm was formed to obtain a photoconductor sample No. 20 of the present invention.

Examples 21 and 22 Electrophotographic photosensitive members Nos. 21 to 2 of the present invention were prepared in the same manner as in Example 20 except that the binder resin in Example 20 was changed as shown in Table 3.
Got 2

Comparative Example 6 Photosensitive member sample No. 23 was obtained in the same manner as in Example 20 except that Polycarbonate C-2 was used as the binder for Comparative Example.

[0141]

[Table 3]

The samples of the present invention and comparative samples were labeled as “LP-3
110 "(manufactured by Konica Corporation) (equipped with a semiconductor laser light source), mounted on a modified machine, the grid voltage V _G is adjusted to 700 [V], the unexposed portion potential V _H and the exposed portion potential V upon irradiation of 0.4 mW. _L was measured. Further, V _H and V _L after 50,000 copies were also measured in an environment of 33 ° C. and 80% RH. Further, the image quality crack generation and the film thickness loss after 50,000 prints were also measured.
The results are shown in Table 4.

[0143]

[Table 4]

From the above results, by using the binder of the present invention, repeated stability under high temperature and high humidity, image quality,
Improvements were made in abrasion resistance and crack prevention.

[0145]

According to the present invention, it is possible to manufacture a photoreceptor having high sensitivity, high printing durability and abrasion resistance, high durability with no cracks, and little deterioration in image quality and reduced sensitivity during actual copying. In addition, it is possible to provide a photoconductor that can be produced using an organic solvent that does not cause environmental damage or explosiveness and that has a good pot life (storability) of the photosensitive layer coating material.

[Brief description of drawings]

FIG. 1 is an X-ray diffraction diagram of Y-type titanyl phthalocyanine preferably used in combination with the binder resin of the present invention.

FIG. 2 is a cross-sectional view of a typical layer structure of the photoconductor of the present invention.

[Explanation of symbols]

 1 Conductive Support 2 Charge Generation Layer (CGL) 3 Charge Transport Layer (CTL) 4 Photosensitive Layer 5 Intermediate Layer 6 Layer Containing Charge Transport Material 7 Charge Generation Material (CGM) 8 Protective Layer

Claims (2)

[Claims] 1. An electrophotographic photoreceptor comprising a photosensitive layer provided on a conductive substrate, wherein the binder resin of the photosensitive layer has a polycarbonate polymer having a repeating structural unit represented by the following general formula [I] or a copolymer thereof. An electrophotographic photoreceptor containing a polymer. [Chemical 1] [Wherein, R _{1 to} R ₈ represent three groups of a hydrogen atom, a halogen atom or a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a cycloalkyl group and an aryl group, and R ₉ and R ₁₀ are at least One of them represents a straight-chain alkyl having 8 to 30 carbon atoms. ] 2. When a solution containing an organic semiconductor and a binder resin is applied onto a conductive substrate to form a photosensitive layer, the binder resin has a repeating structural unit represented by the following general formula [I]. A method for producing an electrophotographic photosensitive member, which comprises coating with a coating liquid containing a polycarbonate polymer or a copolymer thereof. [Chemical 2] [Wherein, R _{1 to} R ₈ represent three groups of a hydrogen atom, a halogen atom or a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a cycloalkyl group and an aryl group, and R ₉ and R ₁₀ are at least One of them represents a straight-chain alkyl having 8 to 30 carbon atoms. ]