JP2003255569A - Monolayer electrophotographic photoreceptor and image forming apparatus using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a monolayer electrophotographic photoreceptor having excellent wear resistance and resistance to gases such as ozone and NOx and ensuring a long service life and to provide an image forming apparatus using the same. <P>SOLUTION: The monolayer electrophotographic photoreceptor has on an electrically conductive substrate monolayer photosensitive layer comprising a binder resin containing at least a charge generating agent and a charge transport agent, wherein the binder resin comprises two copolymerized polycarbonate resins and the proportion of a bisphenol ZC type polycarbonate component among the repeating structural units of each of the copolymerized polycarbonate resins is adjusted to a specified range. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a long-life single-layer type organic electrophotographic photosensitive member having excellent wear resistance (hereinafter sometimes abbreviated as "single-layer type photosensitive member") and its use. The present invention relates to a long-life image forming apparatus such as an electrostatic copying machine, a facsimile, and a laser beam printer.

[0002]

2. Description of the Related Art In the above image forming apparatus, various photoconductors having sensitivity in the wavelength region of the light source used in the apparatus are used. One is an inorganic photoreceptor using an inorganic material such as selenium in the photosensitive layer, and the other is an organic photoreceptor (OPC) using an organic material in the photosensitive layer. Among them, it is easier to manufacture than organic photoreceptors and inorganic photoreceptors, and there are various choices of photoreceptor materials such as charge transport agents, charge generators, binder resins, etc. In recent years, extensive research has been advanced.

The organic photoreceptor has a so-called laminated type photoreceptor having a laminated structure of a charge generating layer containing a charge generating agent and a charge transporting layer containing a charge transferring agent, a charge generating agent and a charge transferring agent. Is a single-layer type photoconductor in which is dispersed in a single photosensitive layer. Among them, the laminated type photoconductor occupies a wide market size. The mainstream of the laminated type photoreceptor is a negative charging type in which a charge generation layer and a charge transport layer are sequentially provided on a conductive substrate.

On the other hand, the single-layer type photoconductor has a simple layer structure and is excellent in productivity, can suppress the occurrence of film defects in the photosensitive layer, and can improve the optical characteristics because there are few interfaces between the layers. It is in the limelight because it has the advantage that one photoconductor can be used for both positive charging type and negative charging type by using an electron transfer agent and a hole transfer agent in combination as the charge transfer agent.

The photoconductor is used in a repeating process of charging, exposure, development, transfer, cleaning and charge removal in the image forming process. The electrostatic latent image formed by the charging exposure is developed with toner which is fine powder. Further, the developed toner is transferred to a transfer material such as paper in the transfer process, but 100% of the toner is not transferred, and a part of the toner remains on the photoconductor. If this residual toner is not removed, a high-quality image without stains cannot be obtained in the repeated process. Therefore, it is necessary to clean the residual toner.

As a cleaning process, a fur brush, a magnetic brush, a blade or the like is typically used, but the blade-shaped resin plate is in direct contact with the photosensitive member in terms of cleaning accuracy and rationalization of the apparatus configuration. Generally, the blade cleaning for cleaning is selected.

While blade cleaning is highly accurate, it increases the mechanical load on the photoconductor. That is, the organic photoreceptor has a lower hardness of the photosensitive layer than the inorganic photoreceptor,
As the number of repeated processes increases, the amount of wear increases, and problems such as a decrease in surface potential and deterioration of sensitivity occur, making it difficult to obtain high-quality images.

On the other hand, in the image forming apparatus equipped with the above-mentioned organic photoconductor, when the charging or transfer means is of the charger type, the photoconductor is exposed to active gas such as ozone or NOx generated by corona discharge. Then, the photosensitive layer-constituting substances (charge-generating agent, charge-transporting agent, etc.) in the binder resin forming the photosensitive layer of the organic photosensitive member are strongly oxidized, and electrical characteristics such as deterioration of charging ability and sensitivity of the photosensitive member are caused. The problem of deterioration tends to occur.

In addition to the above, the charge-generating agent is protected by the charge-transporting layer in the negative charging laminated type photoreceptor, whereas the charge-generating agent is exposed in the single-layer type photoreceptor unless an overcoat layer is provided. It is also present on the outermost surface of the layer. For this reason, in particular, the electric characteristics of the single-layer type photoconductor are likely to deteriorate because the charge generating agent is easily exposed to the active gas such as ozone and NOx generated in the image forming apparatus.

If an organic photoreceptor having deteriorated electrical characteristics is used as it is, image defects such as image fog, black band, dark gray image and thick image character occur as the number of printed sheets increases.

[0011]

From the above, in particular, in the case of a single-layer type photoconductor, a so-called "long-life" photoconductor is designed in which an image defect such as fog does not occur even if the number of printed sheets increases. In that case, simply improving the abrasion resistance of the photosensitive layer makes it difficult for the photosensitive layer surface portion, which is exposed to the active gas generated in the image forming apparatus and has deteriorated electrical characteristics, to be scraped, and as a result, A photoreceptor with a "long life" cannot be obtained.

For example, in order to improve the abrasion resistance of the photosensitive layer, instead of the following bisphenol Z type polycarbonate resin which is generally used as a binder resin, the following bisphenol C type (JP-A-1988-148) is used.
263) or bisphenol ZC type (Japanese Patent Laid-Open No. 1990-
No. 7059) A photoconductor containing a polycarbonate resin as a main component is proposed.

<Bisphenol Z type polycarbonate resin>

[Chemical 14]

<Bisphenol ZC type polycarbonate resin>

[Chemical 15]

<Bisphenol C type polycarbonate resin>

[Chemical 16]

However, the inventors of the present invention produced a single-layer type photoreceptor using the binder resin containing the above bisphenol C type or bisphenol ZC type polycarbonate resin as a main component, and used the single layer type photoreceptor. When a printing test was conducted with an image forming apparatus, as the number of printed sheets increased, the abrasion resistance was improved as compared to the single-layer type photoreceptor using the bisphenol Z-type polycarbonate resin, but the gas resistance was poor and the image was poor. It was clarified that fogging occurs and a long-life single-layer type photoreceptor or image forming apparatus cannot be obtained.

Therefore, an object of the present invention is to provide a "long-life" single-layer type photoreceptor having extremely good abrasion resistance and excellent gas resistance to ozone, NOx, etc., and an image forming apparatus using the same. Is to provide.

[0018]

Means for Solving the Problems and Effects of the Invention As a result of intensive studies to solve the above problems, the present inventors have found that at least a charge-generating agent and a charge-transporting agent are contained on a conductive substrate. A single-layer type photosensitive layer made of a binder resin, wherein the binder resin contains both the copolymerized polycarbonate resin represented by the general formula [1] and the copolymerized polycarbonate resin represented by the general formula [2]. [1];

[Chemical 17] (In the general formula [1], R ¹⁰ and R ¹¹ are the same or different and each independently represent a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, R ¹² and
R ¹³ is the same or different and represents an alkyl group having 1 to 3 carbon atoms, and 0 <a / (a + b) ≦ 0.4 and a + b = 100. ) General formula [2];

[Chemical 18] (In the general formula [2], R ²⁰ and R ²¹ are the same or different and each represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and 0 <c
/(C+d)≦0.4, c + d = 100. ) Further, when the mixing ratio of the copolymeric polycarbonate resin represented by the general formula [1] and the copolymeric polycarbonate resin represented by the general formula [2] is x: y, 0.1 <bx / 10,000 <0 It has been found that the single-layer type electrophotographic photosensitive member characterized by 0.5 and x + y = 100 has extremely good abrasion resistance, excellent gas resistance to ozone and NOx, and a long life.

[0019]

That is, the single-layer type photoreceptor according to the present invention has the copolymerized polycarbonate resin represented by the general formula [1] and the copolymerized polymer represented by the general formula [2]. The greatest feature is that it contains a polycarbonate resin together.

According to the studies by the present inventors, bisphenol Z
The general formula [1-
1] is a biphenyl type polycarbonate component,
Both abrasion resistance and gas resistance were good, but solvent solubility (eg, tetrahydrofuran, methylene chloride, etc.) was extremely poor, and it was difficult to manufacture a photoreceptor.

As described above, the bisphenol ZC type polycarbonate component represented by the general formula [1-2] has good wear resistance but poor gas resistance. The solvent solubility was as good as the bisphenol Z type polycarbonate resin.

General formula [1-1]: Biphenyl type polycarbonate component

[Chemical 19]

General formula [1-2]: Bisphenol ZC type polycarbonate component

[Chemical 20]

The present inventors comprehensively judged the above facts and studied variously. As a result, a copolymer of a biphenyl type polycarbonate and a bisphenol ZC type polycarbonate having a specific copolymerization ratio represented by the general formula [1] was obtained. , General formula [2]
The binder resin prepared by blending a copolymer of biphenyl type polycarbonate and bisphenol Z type polycarbonate having a specific copolymerization ratio shown in a specific weight ratio has no problem in solvent solubility, and has good abrasion resistance and gas resistance. We succeeded in obtaining a simple single-layer type photoreceptor.

Further, as described in claim 2, in the single-layer type photoreceptor of the present invention, the solid content concentration of the binder resin is preferably 50 wt% or more and 80 wt% or less with respect to the total solid content concentration. In order to improve wear resistance, it is ideal to decrease the solid content concentration of the charge transport agent and increase the solid content concentration of the binder resin, but in particular, like the single-layer type photoreceptor of the present invention, When both the hole transporting agent and the electron transporting agent are contained in the photosensitive layer in order to improve electric characteristics (particularly sensitivity), the content of the charge transporting agent is often large.

Therefore, in order to minimize the deterioration of sensitivity even if the solid concentration of the charge transfer agent is reduced, as described in claim 3 or 4, the general formula [3] having a high electron or hole transfer ability is used. ], The general formula [4], the general formula [5], the general formula [6], the general formula [7], the general formula [8], the general formula [9], and the electron transfer agent represented by the general formula [10]. By using the hole-transporting agent represented by the general formula [11], a single-layer type photoreceptor having good sensitivity and good abrasion resistance can be obtained.

On the other hand, as described in claim 5, since the single-layer type photoconductor of the present invention has extremely good wear resistance and gas resistance, at least charging means, exposure means, and Even in an image forming apparatus having a transfer unit and a cleaning unit using a blade, and at least one of the charging unit and the transfer unit is a charger type,
There is little deterioration in the electrical characteristics of the photoconductor due to the increase in the number of printed sheets, and there are no image defects.

[0028]

BEST MODE FOR CARRYING OUT THE INVENTION Next, a single-layer type photosensitive drum according to the present invention and an image forming apparatus using the same will be described in detail.

<Binder Resin> As described above, the single-layer type photoreceptor of the present invention has the biphenyl type polycarbonate of the specific copolymerization ratio represented by the general formula [1] and bisphenol Z.
It contains a binder resin prepared by blending a C-type polycarbonate copolymer and a biphenyl-type polycarbonate and a bisphenol Z-type polycarbonate copolymer having a specific copolymerization ratio represented by the general formula [2] at a specific weight ratio.

The weight ratio (a in the general formula [1] and c in the general formula [2]) of the biphenyl type polycarbonate component of the copolymeric polycarbonate resin represented by the general formula [1] and the general formula [2] is 40 wt. Must be less than or equal to 2
It is more preferably 5 wt% or less. If the weight ratio of the biphenyl type polycarbonate component exceeds 40% by weight, the solvent solubility becomes extremely poor.

Further, the blending ratio of the copolymerized polycarbonate resin represented by the general formula [1] and the general formula [2] (x:
y) needs to be 0.1 <bx / 10,000 <0.5 and x + y = 100. As a result of various studies conducted by the present inventors, among the copolymerized polycarbonate resins represented by the general formula [1] and the general formula [2], the copolymerized polycarbonate resin represented by the general formula [1] Weight ratio of the bisphenol ZC type polycarbonate component of the general formula [1]
When b) therein is more than 10 wt% and less than 50 wt%, it is found that both wear resistance and gas resistance are compatible, and the above relational expression is obtained.

That is, 0.1 <bx / [(a + b) x + (c + d) y] <0.
5 Since a + b = c + d = x + y = 100, ∴0.1 <bx / 10,000 <0.5.

As the weight ratio (bx / 10,000) of the bisphenol ZC type polycarbonate component increases,
As described above, the abrasion resistance of the photosensitive layer is good, but the gas resistance is poor. When it is 0.1 or less, the wear resistance is poor, and when it is 0.5 or more, the gas resistance is poor, so that it cannot be used in practice. Become.

The single-layer type photoconductor of the present invention may contain at least the copolycarbonate resin represented by the general formula [1] and the general formula [2], and examples thereof include a charge generating agent and a charge transporting agent. In order to improve dispersibility, solubility, and adhesion to the conductive substrate, various resins conventionally used in the photosensitive layer may be blended and used.

For example, a styrene-butadiene copolymer,
Styrene-acrylonitrile copolymer, styrene-maleic acid copolymer, acrylic copolymer, styrene-acrylic acid copolymer, polyethylene, ethylene-vinyl acetate copolymer, chlorinated polyethylene, polyvinyl chloride, polypropylene, ionomer, Vinyl chloride-vinyl acetate copolymer, polyester, alkyd resin, polyamide, polyurethane, polycarbonate, polyarylate, polysulfone, diallylphthalate resin, ketone resin, polyvinyl butyral resin, thermoplastic resin such as polyether resin, silicone resin, epoxy resin , Phenolic resin,
It is possible to use resins such as urea resins, melamine resins, other cross-linking thermosetting resins, and photo-curing resins such as epoxy acrylate and urethane-acrylate. Further, these binder resins can be used alone, or two or more kinds thereof can be copolymerized or blended and used.

As described above, it goes without saying that when it is blended with another conventionally known binder resin, it is used within a range that does not adversely affect the wear resistance and gas resistance.

The weight average molecular weights of the copolymeric polycarbonate resin represented by the general formula [1] and the general formula [2], and all the above binder resins are 10,000 to 500,0.
00, and more preferably 30,000 to 200,000.

In the single-layer type photoreceptor of the present invention, the solid content concentration of the binder resin is preferably 50 wt% or more and 80 wt% or less with respect to the total solid content concentration. As the solid content concentration of the binder resin increases, the abrasion resistance improves but the sensitivity deteriorates. Therefore, as described above, it is necessary to properly select the type of charge transfer agent.

<Electron Transfer Agent> In the single-layer type photoconductor of the present invention, conventionally known electron transfer agents may be used alone or in combination of two or more kinds. In particular, the general formula [3], General formula [4], general formula [5], general formula [6], general formula [7], general formula [8], general formula [9], general formula [10]
It is preferable to contain at least one selected from the compounds represented by

Examples of other conventionally known electron transfer agents include, for example, diphenoquinone derivatives, benzoquinone derivatives, anthraquinone derivatives, malononitrile derivatives, thiopyran derivatives, trinitrothioxanthone derivatives,
3,4,5,7-tetranitro-9-fluorenone derivative, dinitroanthracene derivative, dinitroacridine derivative, nitroantharaquinone derivative, dinitroanthraquinone derivative, tetracyanoethylene, 2,4,8
Examples include various compounds having an electron accepting property such as trinitrothioxanthone, dinitrobenzene, dinitroanthracene, dinitroacridine, nitroanthraquinone, dinitroanthraquinone, succinic anhydride, maleic anhydride, and dibromomaleic anhydride.

<Hole Transfer Agent> In the single-layer type photoconductor of the present invention, conventionally known hole transfer agents may be used alone or in combination of two or more kinds. In particular, the general formula [11] is used.
It is preferable to contain a compound represented by

Other well-known hole transporting agents are, for example, N, N, N ', N'-tetraphenylbenzidine derivatives, N, N, N', N'-tetraphenylphenylenediamine derivatives, and N, N. , N ', N'-tetraphenylnaphthylenediamine derivative, N, N, N', N'-tetraphenylphenanthrylenediamine derivative, 2,5
An oxadiazole-based compound such as di (4-methylaminophenyl) -1,3,4-oxadiazole, 9- (4
-Diethylaminostyryl) anthracene and other styryl compounds, polyvinylcarbazole and other carbazole compounds, organic polysilane compounds, 1-phenyl-3-
Pyrazoline compounds such as (p-dimethylaminophenyl) pyrazoline, hydrazone compounds, indole compounds, oxazole compounds, isoxazole compounds, thiazole compounds, thiadiazole compounds, imidazole compounds, pyrazole compounds, triazole compounds And the like, and condensed polycyclic compounds.

<Charge Generating Agent> Examples of the charge generating agent used in the single-layer type photoconductor of the present invention include metal-free phthalocyanine, oxotitanyl phthalocyanine, hydroxygallium phthalocyanine, perylene pigments, bisazo pigments, dioketopyrrolo pigments. Pyrrole pigments, metal-free naphthalocyanine pigments, metal naphthalocyanine pigments, squaraine pigments, trisazo pigments, indigo pigments, azurenium pigments, cyanine pigments, pyrylium pigments, ansanthuron pigments, triphenylmethane pigments, thren pigments, toluidine pigments, Examples include conventionally known charge generating agents such as organic photoconductors such as pyrazoline pigments and quinacridone pigments, and inorganic photoconductive materials such as selenium, selenium-tellurium, selenium-arsenic, cadmium sulfide, and amorphous silicon.

The charge generating agents exemplified above can be used alone or in combination of two or more so as to have an absorption wavelength in a desired region.

Among the charge generating agents exemplified above, particularly in a digital optical system image forming apparatus such as a laser beam printer or a facsimile using a light source such as a semiconductor laser,
Since a photoreceptor having sensitivity in the wavelength region of 700 nm or more is required, for example, as described in claim 6, phthalocyanine pigments such as metal-free phthalocyanine, oxotitanyl phthalocyanine, and hydroxygallium phthalocyanin are preferably used. The crystal type of the phthalocyanine-based pigment is not particularly limited, and various types can be used.

The charge generating agent in the above example is 0.1 to 20% by weight, more preferably 0.5 to 15% by weight based on the total weight of the binder resin.
It is preferable to contain wt%.

The photosensitive layer thickness of the single-layer type photoreceptor of the present invention is 5 to
The thickness is preferably 100 μm, more preferably 10 to 50 μm.

In the photosensitive layer, in addition to the above-mentioned components, various conventionally known additives such as an antioxidant, a radical scavenger, a singlet quencher, and the like can be used as long as they do not adversely affect the electrophotographic characteristics. Deterioration inhibitors such as UV absorbers, softeners,
A plasticizer, a surface modifier, a bulking agent, a thickener, a dispersion stabilizer, a wax, an acceptor, a donor and the like can be added. In order to improve the sensitivity of the photosensitive layer, for example,
Known sensitizers such as terphenyl, halonaphthoquinones, and acenaphthylene may be used in combination with the charge generating agent.

A barrier layer may be formed between the support and the photosensitive layer within the range not impairing the characteristics of the photosensitive member.

As the support on which the photosensitive layer is formed, various conductive materials can be used.
Iron, aluminum, copper, tin, platinum, silver, vanadium,
Molybdenum, chromium, cadmium, titanium, nickel,
Examples include simple metals such as palladium, indium, stainless steel, and brass, plastic materials obtained by vapor deposition or lamination of the above metals, and glass covered with aluminum iodide, tin oxide, indium oxide, or the like.

The shape of the support may be any of a sheet shape, a drum shape and the like, depending on the structure of the image forming apparatus used, and the support itself has conductivity or the surface of the support is It only needs to have conductivity. In addition, the support preferably has sufficient mechanical strength when used.

When the photosensitive layer is formed by a coating method, the charge generating agent, charge transporting agent, binder resin and the like exemplified above may be used together with a suitable solvent by a known method, for example, roll mill, ball mill, attritor, paint coater. The dispersion may be prepared by dispersing and mixing using an acre, an ultrasonic disperser or the like, and the dispersion may be applied by a known means and dried.

As the solvent for preparing the above dispersion liquid, various organic solvents can be used. Examples thereof include alcohols such as methanol, ethanol, isopropanol, butanol, and aliphatic compounds such as n-hexane, octane and cyclohexane. Hydrocarbons, aromatic hydrocarbons such as benzene, toluene, xylene, halogenated hydrocarbons such as dichloromethane, dichloroethane, chloroform, carbon tetrachloride, chlorobenzene, dimethyl ether, diethyl ether, tetrahydrofuran, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, etc. Ethers, acetone, ketones such as methyl ethyl ketone and cyclohexanone, esters such as ethyl acetate and methyl acetate, dimethylformaldehyde, dimethylformamide, dimethylsu Examples include luhoxide. These solvents may be used alone or in combination of two or more.

Further, in order to improve the dispersibility of the charge generating agent, the charge transporting agent and the like and the smoothness of the surface of the photosensitive layer, a surfactant, a leveling agent and the like may be used.

[0055]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described below with reference to Examples and Comparative Examples. The following embodiments are examples of embodying the present invention, and do not limit the technical scope of the present invention.

Examples and Comparative Examples 3.5 parts by weight of X-type metal-free phthalocyanine as a charge generating agent, 60 parts by weight of HTM-1 as a hole transferring material, and ETM as an electron transferring material.
-1 of 30 parts by weight as a binder resin, a polycarbonate having a weight average molecular weight of 80,000 (Resin-
1) and a polycarbonate resin having a weight average molecular weight of 80,000 (Resin-2), or a polycarbonate resin having a weight average molecular weight of 80,000 (Resin-).
1) Resin alone or polycarbonate (Resin-2) resin having a weight average molecular weight of 80,000 alone, 100 parts by weight each of which is dispersed or dissolved together with 750 parts by weight of tetrahydrofuran in a ball mill for 20 hours, and applied for a single layer type photosensitive layer. The liquid was prepared. Then, this coating solution is applied onto an aluminum base tube as a support by a dip coating method and dried with hot air at 130 ° C. for 35 minutes to obtain a single-layer type photoreceptor having a single photosensitive layer having a film thickness of 26 μm. Was produced.

<HTM-1>

[Chemical 21]

<ETM-1>

[Chemical formula 22]

<Resin-1>

[Chemical formula 23]

<Resin-2>

[Chemical formula 24]

The following evaluation tests were carried out on the single-layer type photoreceptors of the above Examples and Comparative Examples.

<Abrasion Resistance Evaluation Test> A digital copying machine (“Creage 7340” manufactured by Kyocera Mita Co., Ltd.) having the charging means of the single layer type photoreceptor of each of the examples and the comparative example and having a cleaning means of a blade is used. Then, a printing test of 500,000 sheets of A4 horizontal size paper was carried out, the film thickness of the photosensitive layer before and after the printing test was measured, and the film thickness change amount was calculated. A smaller amount of change in film thickness indicates better wear resistance, and a case of less than 4.0 μm is acceptable.
It was judged that μm or more was impossible.

<Ozone Resistance Evaluation Test> The surface potentials of the single-layer photoconductors of Examples and Comparative Examples were measured by using a digital copying machine (“Creage 7340” manufactured by Kyocera Mita Co., Ltd.), and then the above-mentioned single The layered photoreceptor is exposed in an atmosphere having an ozone concentration of 15 ppm in the dark at room temperature for 8 hours,
The surface potential immediately after the exposure was measured in the same manner. (Initial surface potential) − (Surface potential immediately after exposure) = ΔV _0, and the smaller ΔV ₀ is, the better the ozone resistance of the photoconductor is, that is, 65V or less is acceptable, and 65V or less is not acceptable.

The evaluation results are shown in Table 1. In addition, the ratio of the bisphenol ZC type polycarbonate component in all the binder resins (bx / 10,000), the amount of wear and ΔV ₀
The relationship with is shown in FIGS. 1 and 2, respectively.

[0065]

[Table 1]

From Table 1, FIG. 1 and FIG. 2, bisphenol Z is obtained.
Ratio of C-type polycarbonate component (bx / 10,00
As 0) increased, the wear resistance was improved and the gas resistance was deteriorated.

Further, as shown in Comparative Example 5, Resin
In -1, if the weight ratio of the biphenyl-type polycarbonate component exceeds 40 wt%, it becomes partially insoluble in the solvent, making it impossible to produce a photoreceptor.

[0068]

As described above, a single-layer type photosensitive layer made of a binder resin containing at least a charge generating agent and a charge transporting agent is provided on a conductive substrate, and the binder resin is represented by the general formula [1 ] The copolymer of biphenyl type polycarbonate and bisphenol ZC type polycarbonate of the specific copolymerization ratio shown by these, and the copolymer of the biphenyl type polycarbonate and bisphenol Z type polycarbonate of the specific copolymerization ratio shown by general formula [2], It was possible to obtain a single-layer type photoreceptor in which the binder resin blended at a specific weight ratio has no problem in solvent solubility and has good abrasion resistance and gas resistance.

[0069]

[Brief description of drawings]

FIG. 1 is a graph showing the relationship between the wear amount and the ratio of a bisphenol ZC type polycarbonate component in the binder resin of the single-layer type photoreceptors manufactured in Examples and Comparative Examples.

FIG. 2 is a graph showing the relationship between ΔV ₀ and the ratio of the bisphenol ZC type polycarbonate component in the binder resin of the single-layer type photoreceptors manufactured in Examples and Comparative Examples.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) G03G 5/06 319 G03G 5/06 319 F term (reference) 2H068 AA13 AA20 AA31 BA12 BA13 BA14 BA16 BA42 BA44 BA63 BA64 BB25 BB53 BB54

Claims (5)

[Claims] 1. A monolayer type photosensitive layer comprising a binder resin containing at least a charge generating agent and a charge transporting agent on a conductive substrate, wherein the binder resin is a copolymer represented by the general formula [1]. A polycarbonate resin and a copolymerized polycarbonate resin represented by the general formula [2] are both contained, and the general formula [1]; (In the general formula [1], R ¹⁰ and R ¹¹ are the same or different and each independently represent a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, R ¹² and
R ¹³ is the same or different and represents an alkyl group having 1 to 3 carbon atoms, and 0 <a / (a + b) ≦ 0.4 and a + b = 100. ) General formula [2]; (In the general formula [2], R ²⁰ and R ²¹ are the same or different and each represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and 0 <c
/(C+d)≦0.4, c + d = 100. ) Further, when the mixing ratio of the copolymeric polycarbonate resin represented by the general formula [1] and the copolymeric polycarbonate resin represented by the general formula [2] is x: y, 0.1 <bx / 10,000 <0 0.5, x + y = 100, A single-layer type electrophotographic photosensitive member. 2. The single-layer type electrophotographic photosensitive member according to claim 1, wherein the solid content concentration of the binder resin is 50 wt% or more and 80 wt% or less with respect to the total solid content concentration. 3. The charge transfer agent as an electron transfer agent represented by the general formulas [3], [4], [5], [6], [7], [8],
3. At least one selected from the compounds represented by [9] and [10] is contained.
The single-layer electrophotographic photosensitive member described. General formula [3]; (In the general formula [3], R ³⁰ and R ³¹ are the same or different and each represents an alkyl group which may have a substituent.) General formula [4]; (In the general formula [4], R ⁴⁰ and R ⁴¹ are the same or different and each represents an alkyl group which may have a substituent.) General formula [5]; (In the general formula [5], R ⁵⁰ and R ⁵¹ are the same or different and each independently represent a monovalent hydrocarbon group which may have a substituent.) General formula [6]; (In the general formula [6], R ⁶⁰ represents a halogen atom, an alkyl group or an aryl group which may have a substituent, and R ⁶¹ represents an alkyl group or an aryl group which may have a substituent, or a group: .R ^61a showing a -O-R ^61a represents an alkyl group or an aryl group which may have a substituent) general formula [7];. embedded image (In the general formula [7], R ⁷⁰ , R ⁷¹ , R ⁷² , and R ⁷³ are the same or different and each represents an alkyl group which may have a substituent.) General formula [8]; (In the general formula [8], R ^{80 to} R ⁸³ are the same or different and each is a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, or 1 to 1 carbon atoms.
2, an alkoxy group, an aryl group which may have a substituent,
A cycloalkyl group, an aralkyl group which may have a substituent and a halogenated alkyl group are shown. The substituent is a halogen atom, an alkoxy group having 1 to 6 carbon atoms, a hydroxyl group, a cyano group, an amino group, a nitro group or a halogenated alkyl group. ) General formula [9]; (In the general formula [9], R ⁹⁰ and R ⁹¹ are the same or different and each is a hydrogen atom, an alkyl group having 1 to 12 carbons, or 1 to 1 carbons.
2, an alkoxy group, an aryl group which may have a substituent,
A cycloalkyl group, an aralkyl group which may have a substituent and a halogenated alkyl group are shown. R ^{92 to} R ⁹⁶ are the same or different and each is a hydrogen atom, a halogen atom, or a carbon number of 1 to 1.
2 represents an alkyl group, an alkoxy group having 1 to 12 carbon atoms, an aralkyl group which may have a substituent, a phenoxy group which may have a substituent, and a halogenated alkyl group.
One or more groups may combine to form a ring. The substituent is
Halogen atom, C1-C6 alkyl group, C1-C1
6 represents an alkoxy group, a hydroxyl group, a cyano group, an amino group, a nitro group and a halogenated alkyl group. ) General formula [10]; (In the general formula [10], R ^{100 to} R ¹⁰³ are the same or different and each is a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, or 1 carbon atom.
To 12 are an alkoxy group, an aryl group which may have a substituent, a cycloalkyl group, an aralkyl group which may have a substituent and a halogenated alkyl group. R ¹⁰⁴ and R ¹⁰⁵ are
The same or different, a hydrogen atom and a C1-C12 alkyl group are shown. R ^{106 to} R ¹¹³ are the same or different and each is a hydrogen atom, a halogen atom, an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an aryl group which may have a substituent, a halogenated alkyl group. Indicates. The substituent is a halogen atom, an alkyl group having 1 to 6 carbon atoms, or 1 to 6 carbon atoms.
Represents an alkoxy group, a hydroxyl group, a cyano group, an amino group, a nitro group, and a halogenated alkyl group. ) 4. The single-layer type electrophotographic photoconductor according to claim 1, wherein the charge transfer material contains a compound represented by the general formula [11] as a hole transfer material. General formula [11]; (In the general formula [11], R ¹¹⁰ , R ¹¹¹ , R ¹¹² and R ¹¹³ are the same or different and each represents an alkyl group, an alkoxy group, an aryl group, an aralkyl group or a halogen atom,
m, n, p and q are the same or different and each represents an integer of 0 to 3. R ¹¹⁴ and R ^{1 15} are the same or different and represent a hydrogen atom or an alkyl group. In addition, -X- is Or [Chemical 13] Indicates. ) 5. A photosensitive drum is provided with at least a charging unit, an exposing unit, a transferring unit, and a cleaning unit using a blade, and at least one of the charging unit or the transferring unit is of a charger type, and the photosensitive member. An image forming apparatus, wherein the drum is the single-layer electrophotographic photosensitive drum according to claim 1, 2, 3, or 4.