JP2009276484A - Electrophotographic photoreceptor and electrophotographic apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electrophotographic photoreceptor which can ensure high responsiveness even in a long wavelength range and also has high stability without deterioration of electric properties even during repeated use. <P>SOLUTION: The electrophotographic photoreceptor includes a conductive support and a photosensitive layer containing at least a charge generator, a charge transfer agent and a binder resin, which is laminated on the conductive support. The charge generator is chlorogallium phthalocyanine, the charge transfer agent contains a compound represented by general formula [I]. In the formula, R<SB>1</SB>-R<SB>3</SB>each independently represent hydrogen atom, a halogen atom, a 1-6C alkyl group which may have a substituent, or a 6-12C substituted or non-substituted aryl group. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an electrophotographic photoreceptor containing chlorogallium phthalocyanine as a charge generator and a specific compound as a charge transfer agent.

  In recent years, long-wavelength light sources such as semiconductor lasers and LEDs have been mainly used as exposure light sources for non-impact printers that employ electrophotography. Furthermore, along with the downsizing and speeding up of copying machines and printers, processes have been adopted in which the diameter of the photoreceptor is reduced and the peripheral speed is high. Therefore, the electrophotographic photosensitive member generally uses a charge generating agent having sensitivity in a long wavelength region. Conventionally, phthalocyanine pigments are often used as such materials. It is well known that the sensitivity or stability of this phthalocyanine pigment varies depending on the added metal or crystal type. In addition, with the widespread use of personal computers, the use environment of electrophotographic apparatuses such as printers has also diversified, so that there is an increasing demand for stable images.

Among the phthalocyanine pigments, chlorogallium phthalocyanine is mentioned as one having sensitivity in a long wavelength region and excellent in repetitive stability. Several crystal forms of chlorogalliphthalocyanine have been introduced. Among them, those showing diffraction peaks of Bragg angles (2θ) of 7.4 °, 16.6 °, 25.5 ° and 28.3 °. It is said to be excellent in repeated stability. However, when used in a high-speed process, the potential characteristics of the photoreceptor after repeated use deteriorate, and fog, black streaks, density unevenness and the like occur in the obtained image. When used in a high-speed process, if the photoresponsiveness is not sufficient, charges remain in the photosensitive layer, causing fogging, black streaks, density unevenness, etc. in the next electrophotographic process. As a charge transfer agent, it is necessary to have a high charge transport capability, and a combination of a charge generation agent and a charge transport agent is important. For example, Patent Document 1 discloses a charge transfer agent having a stable charge potential, residual potential and sensitivity even when used for a long time.
Japanese Patent Laid-Open No. 1-106069

  Therefore, an electrophotographic photosensitive member having sensitivity in a long wavelength region, high responsiveness, and stable reproducibility of electrophotographic characteristics, particularly initial potential and potential after repeated use, even when repeatedly used at high speed. It has been demanded. In addition, even if a charge generating agent having high charge generation efficiency is used, sufficient sensitivity cannot be obtained if the compatibility with the charge transfer agent is poor, and it is also high in various usage environments from high temperature and high humidity to low temperature and low humidity. Quality image is not obtained. The compatibility between charge generators and charge transfer agents has been studied from various viewpoints, and it has been previously studied to use chlorogallium phthalocyanine with a specific crystal structure and a triphenylamine-based charge transport material in an electrophotographic photoreceptor. However, the current situation is not clearly found.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a photoconductor that can cope with a process in which the diameter of the photoconductor is reduced and the peripheral speed is fast as the copying machine and the printer apparatus are miniaturized and increased in speed, and has high responsiveness even in a long wavelength region. Thus, it is an object of the present invention to provide an electrophotographic photosensitive member that has no deterioration in electrical characteristics even after repeated use and has high stability.

As a result of intensive studies to solve the above problems, the present inventors have found that an electrophotographic photoreceptor using chlorogallium phthalocyanine as a charge generating agent and a specific compound as a charge transfer agent is a problem of the conventional technique. The present inventors have found that the problems can be solved and have completed the present invention.
That is, the present invention relates to an electrophotographic photosensitive member as described below and an electrophotographic apparatus using the same.

(1) In an electrophotographic photosensitive member obtained by laminating a photosensitive layer containing at least a charge generating agent, a charge transfer agent and a binder resin on a conductive support, the charge generating agent is chlorogallium phthalocyanine, An electrophotographic photoreceptor, wherein the charge transfer agent comprises a compound represented by the following general formula [I].

〔式中、Ｒ_１〜Ｒ_３は、各々独立に水素、ハロゲン原子、置換基を有してもよい炭素数１〜６のアルキル基、炭素数６〜１２の置換若しくは無置換のアリ−ル基を表す。〕
（２）前記一般式（Ｉ）で表される化合物が下記式（Ｉａ）で表される化合物であることを特徴とする（１）に記載の電子写真感光体。

[Wherein R _{1 to} R ₃ each independently represents hydrogen, a halogen atom, an optionally substituted alkyl group having 1 to 6 carbon atoms, or a substituted or unsubstituted aryl having 6 to 12 carbon atoms. Represents a group. ]
(2) The electrophotographic photoreceptor according to (1), wherein the compound represented by the general formula (I) is a compound represented by the following formula (Ia).

(3) The electrophotographic photosensitive member according to (1), wherein the compound represented by the general formula (I) is a compound represented by the following formula (Ib).

(4) The electrophotographic photosensitive member according to (1), wherein the compound represented by the general formula (I) is a compound represented by the following formula (Ic).

(5) The electrophotographic photoreceptor described in (1), wherein the compound represented by the general formula (I) is a compound represented by the following formula (Id).

(6) The chlorogallium phthalocyanine has strong diffraction peaks at Bragg angles (2θ ± 0.2 °) of 7.4 °, 16.6 ° 25.5 °, and 28.3 ° (1 The electrophotographic photosensitive member according to any one of (5) to (5).
(7) The photosensitive layer includes a charge generation layer containing a charge generation agent formed on a conductive support, and a charge transfer layer containing a charge transfer agent formed on the charge generation layer. The electrophotographic photosensitive member according to any one of (1) to (6).
(8) The electrophotographic photosensitive member according to any one of (1) to (7), wherein the photosensitive layer contains a hindered phenol-based antioxidant.
(9) The electrophotographic photosensitive member according to any one of (1) to (8), wherein the photosensitive layer contains an amine-based antioxidant.
(10) The electrophotographic photosensitive member according to any one of (1) to (9), wherein the photosensitive layer contains a sulfur-based antioxidant.
(11) The electrophotographic photosensitive member according to any one of (1) to (10), wherein the photosensitive layer contains a benzotriazole ultraviolet absorber.
(12) An electron which has a photosensitive member and a charging member to which a voltage is applied so as to be in contact with the photosensitive member, and performs charging, exposure, development, transfer, and static elimination (including cases where there is no static elimination). An electrophotographic apparatus, wherein the photoconductor is the electrophotographic photoconductor according to any one of (1) to (11).

The electrophotographic photosensitive member combining the charge generating agent and the charge transfer agent of the present invention has a very low residual potential, and exhibits excellent electrophotographic characteristics without showing an afterimage even when used in an eraseless electrophotographic apparatus. I discovered that.
As can be seen from the characteristic differences between Examples and Comparative Examples described later, the electrophotographic photosensitive member of the present invention has high responsiveness, repeat stability, and can meet high market demands.

The electrophotographic photoreceptor of the present invention is obtained by incorporating chlorogallium phthalocyanine having a specific X-ray diffraction spectrum into a photosensitive layer on a substrate as a charge generating material.
A preferred embodiment of the electrophotographic photosensitive member according to the present invention will be described in detail. In the present invention, for example, a function-separated electrophotographic image in which a charge generation layer containing at least a charge generation agent is formed on a conductive support and a charge transfer layer containing at least a charge transfer agent is formed thereon. It is applied to a photoreceptor. In this case, a photosensitive layer is formed by the charge generation layer and the charge transfer layer.

  Various methods can be used as a method for forming the charge generation layer. For example, a coating solution in which the chlorogallium phthalocyanine in the present invention is used as a charge generation agent and dispersed or dissolved in a suitable solvent together with a binder resin is used. It can apply | coat on the support body used as the foundation | substrate of this, and can dry and form as needed.

The charge transfer layer has at least a charge transfer agent, which will be described later. This charge transfer layer is formed, for example, by binding the charge transfer agent on the charge generation layer serving as the base using a binder resin. be able to.
Various methods can be used as a method for forming the charge transfer layer. In general, a coating solution in which a charge transfer agent is dispersed or dissolved in a suitable solvent together with a binder resin is applied to the underlying charge generation layer. The method of apply | coating to and drying can be used.

  The present invention can also be applied to an inversely laminated electrophotographic photosensitive member in which a charge generation layer and a charge transfer layer are laminated upside down. Furthermore, the present invention can also be applied to a single layer type electrophotographic photosensitive member containing a charge generating agent and a charge transfer agent in the same layer.

  Examples of the conductive support that can be used in the present invention include aluminum, brass, stainless steel, nickel, chromium, titanium, gold, silver, copper, tin, platinum, molybdenum, indium, and other simple metals and alloys thereof. The body is mentioned. The shape may be any shape as long as it is a flexible shape such as a sheet shape, a film shape, or a belt shape, and may be endless or endless. The diameter of the conductive support is particularly effective when it is 60 mm or less, preferably 30 mm or less.

  Among these, aluminum alloys such as JIS 3000, JIS 5000, and JIS 6000 are used, and general methods such as EI (Extension Ironing) method, ED (Extension Drawing) method, DI (Drawing Ironing) method, II (Impact Ironing) method, etc. A conductive support formed by the method is preferable, and the surface of the conductive support is further subjected to surface treatment such as diamond cutting or polishing, surface treatment such as polishing, anodizing treatment, or the like. Anything such as a non-cutting tube may be used.

Moreover, when using resin as a base | substrate, conductive agents, such as metal powder and conductive carbon, can be contained in resin, and conductive resin can also be used as base | substrate formation resin.
Further, when glass is used for the substrate, the surface thereof may be coated with tin oxide, indium oxide, or aluminum iodide so as to have conductivity.

  Further, a resin layer may be formed on the support. This resin layer has an adhesion improving function, a barrier function for preventing an inflow current from the aluminum tube, a defect covering function on the surface of the aluminum tube, and the like. Various resins such as polyethylene resin, acrylic resin, epoxy resin, polycarbonate resin, polyurethane resin, vinyl chloride resin, vinyl acetate resin, polyvinyl butyral resin, polyamide resin, nylon resin, alkyd resin, and melamine resin are used for this resin layer. be able to. These resin layers may be composed of a single resin or a mixture of two or more resins. Moreover, a metal compound, carbon, silica, resin powder, etc. can be dispersed in the layer. Furthermore, various pigments, electron accepting substances, electron donating substances, and the like can be contained for improving the characteristics.

  As a charge generator, a strong diffraction peak at Bragg angles (2θ ± 0.2 °) of 7.4 °, 16.6 °, 25.5 ° and 28.3 ° in an X-ray diffraction spectrum using CuKα as a radiation source A chlorogallium phthalocyanine having the following formula is preferably used.

  In addition to the chlorogallium phthalocyanine of the present invention, phthalocyanines other than the present invention, azo pigments, and the like can be mixed in the photosensitive layer in order to obtain an appropriate photosensitivity wavelength and sensitizing action. These are desirable in terms of good sensitivity compatibility. Other examples include monoazo pigments, bisazo pigments, trisazo pigments, polyazo pigments, indigo pigments, selenium pigments, toluidine pigments, pyrazoline pigments, perylene pigments, quinacridone pigments, and pyrylium salts.

  As binder resin for forming the photosensitive layer, polycarbonate resin, styrene resin, acrylic resin, styrene-acrylic resin, ethylene-vinyl acetate resin, polypropylene resin, vinyl chloride resin, chlorinated polyether, vinyl chloride-vinyl acetate resin Polyester resin, furan resin, nitrile resin, alkyd resin, polyacetal resin, polymethylpentene resin, polyamide resin, polyurethane resin, epoxy resin, polyarylate resin, diarylate resin, polysulfone resin, polyethersulfone resin, polyallylsulfone resin, Silicone resin, ketone resin, polyvinyl butyral resin, polyether resin, phenol resin, EVA (ethylene-vinyl acetate) resin, ACS (acrylonitrile, chlorinated polyethylene, styrene) Resins, ABS (acrylonitrile butadiene styrene) is a resin and epoxy arylate such resins.

They may be used alone or in combination of two or more. It is preferable to use a mixture of resins having different molecular weights because the hardness and wear resistance can be improved.
In the case where the photosensitive layer comprises a charge generation layer and a charge transfer layer, the resin can be applied to either layer.

  Solvents used in the coating solution include alcohols such as methanol, ethanol, n-propanol, i-propanol and butanol, saturated aliphatic hydrocarbons such as pentane, hexane, heptane, octane, cyclohexane and cycloheptane, toluene and xylene. Aromatic hydrocarbons such as dichloromethane, chlorinated hydrocarbons such as dichloromethane, dichloroethane, chloroform, chlorobenzene, ethers such as dimethyl ether, diethyl ether, tetrahydrofuran (THF), methoxyethanol, ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone , Esters such as ethyl formate, propyl formate, methyl acetate, ethyl acetate, propyl acetate, butyl acetate, methyl propionate, diethyl ether, dimethoxyethane, tetrahydride Furan, dioxolane, dioxane or ether solvents such as anisole,, N, N-dimethylformamide, there are dimethyl sulfoxide and the like. Among these, ketone solvents, ester solvents, ether solvents, or halogenated hydrocarbon solvents are preferable, and these can be used alone or as a mixed solvent of two or more.

  The electrophotographic photoreceptor of the present invention contains a compound represented by the following general formula [I] as a charge transfer agent.

〔式中、Ｒ_１〜Ｒ_３は、各々独立に水素、ハロゲン原子、置換基を有してもよい炭素数１〜６のアルキル基、炭素数６〜１２の置換若しくは無置換のアリ−ル基を表す。〕

[Wherein R _{1 to} R ₃ each independently represents hydrogen, a halogen atom, an optionally substituted alkyl group having 1 to 6 carbon atoms, or a substituted or unsubstituted aryl having 6 to 12 carbon atoms. Represents a group. ]

The charge transfer agent has good compatibility with chlorogallium phthalocyanine and can provide an electrophotographic photosensitive member having high environmental resistance.
Of the compounds represented by the general formula [I], the compounds represented by the formulas [Ia] to [Id] are particularly preferable because of their good compatibility with chlorogallium phthalocyanine.
Specific compounds are shown below, but the present invention is not limited to these.

  In this case, the content of the compound represented by the general formula [I] in the charge transfer layer is preferably 0.3 to 2.0 parts by mass with respect to 1 part by mass of the binder resin. If the content of this compound is less than 0.3 parts by mass, the electrical characteristics deteriorate, such as an increase in residual potential. On the other hand, when the amount is more than 2.0 parts by mass, mechanical properties such as wear resistance deteriorate.

  Furthermore, the compound represented by the general formula [I] and other charge transfer agents can be mixed and used. In this case, the content ratio of the compound of the general formula [I] and other compounds is in the range of [I]: other compounds = 50: 50 to 95: 5, preferably 70:30 to 95: 5.

  Other charge transfer agents include polyvinyl carbazole, halogenated polyvinyl carbazole, polyvinyl pyrene, polyvinyl indoloquinoxaline, polyvinyl benzothiophene, polyvinyl anthracene, polyvinyl acridine, polyvinyl pyrazoline, polyacetylene, polythiophene, polypyrrole, polyphenylene, polyphenylene vinylene, poly Conductive polymer compounds such as isothianaphthene, polyaniline, polydiacetylene, polyheptadiene, polypyridinediyl, polyquinoline, polyphenylene sulfide, polyferrocenylene, polyperinaphthylene, and polyphthalocyanine can be used. In addition, as low molecular compounds, trinitrofluorenone, tetracyanoethylene, tetracyanoquinodimethane, quinone, diphenoquinone, naphthoquinone, anthraquinone and derivatives thereof, polycyclic aromatic compounds such as anthracene, pyrene, phenanthrene, indole, carbazole, Nitrogen-containing heterocyclic compounds such as imidazole, fluorenone, fluorene, oxadiazole, oxazole, pyrazoline, hydrazone, triphenylmethane, triphenylamine, enamine, stilbene and the like can be used. Further, a polymer solid electrolyte in which a polymer compound such as polyethylene oxide, polypropylene oxide, polyacrylonitrile, polymethacrylic acid or the like is doped with a metal ion such as Li ion can also be used. Furthermore, an organic charge transfer complex formed of an electron donating compound typified by tetrathiafulvalene-tetracyanoquinodimethane and an electron accepting compound, etc. can be used. Desired photoreceptor characteristics can be obtained by mixing and adding the above compounds.

  In the coating solution for producing the electrophotographic photosensitive member of the present invention, an antioxidant, an ultraviolet absorber, a radical scavenger, a softener, a curing agent, a crosslinking agent, etc. are added as long as the characteristics are not impaired. The characteristics, durability, and mechanical characteristics of the photoreceptor can be improved. In particular, the use of an antioxidant and an ultraviolet absorber alone or in combination contributes to improving the durability of the photoreceptor and is useful. Among them, it is preferable to add a hindered phenol-based antioxidant, an amine-based antioxidant, a sulfur-based antioxidant, and a benzotriazole-based ultraviolet absorber to the photosensitive layer.

  For example, the phenolic antioxidant is 2.6-di-tert-butylphenol, 2.6-di-tert-4-methoxyphenol, 2-tert-butyl-4-methoxyphenol, 2.4-dimethyl-6. -Tert-butylphenol, 2.6-di-tert-butyl-4-methylphenol, butylated hydroxyanisole, stearyl propionate-β- (3.5-di-tert-butyl-4-hydroxyphenyl), α- Monophenols such as tocopherol, β-tocopherol, n-octadecyl-3- (3′-5′-di-tert-butyl-4′-hydroxyphenyl) propionate, 2.2′-methylenebis (6-tert-butyl) -4-methylphenol), 4.4'-butylidene-bis- (3-methyl-6-tert) Butylphenol), 4.4'-thiobis (6-tert-butyl-3-methylphenol), 1.1.3-tris (2-methyl-4-hydroxy-5-tert-butylphenyl) butane, 1.3 .5-trimethyl-2.4.6-tris (3.5-di-tert-butyl-4-hydroxybenzyl) benzene, tetrakis [methylene-3 (3.5-di-tert-butyl-4-hydroxyphenyl) ) Propionate] Polyphenols such as methane are preferred, and one or more of them can be simultaneously contained in the photosensitive layer.

  For example, amine antioxidants include N-phenyl-1-naphthylamine, N-phenyl-N′-isopropyl-p-phenylenediamine, N, N-diethyl-p-phenylenediamine, N-phenyl-N′-ethyl. -2-methyl-p-phenylenediamine, N-ethyl-N-hydroxyethyl-p-phenylenediamine, alkylated diphenylamine, N, N'-diphenyl-p-phenylenediamine, N, N'-diallyl-p-phenylene Diamine, N-phenyl-1,3-dimethylbutyl-p-phenylenediamine, 4,4'-dioctyl-diphenylamine, 4,4'-dioctyl-diphenylamine, 6-ethoxy-2,2,4-trimethyl-1, 2-dihydroquinoline, 2,2,4-trimethyl-1,2-dihydroquinoline, N-fluoro Cycloalkenyl -β- naphthylamine, N, N'-di-2-naphthyl -p- phenylenediamine, and the like. One or more of these can be simultaneously contained in the photosensitive layer.

  Sulfur-based antioxidants include dilauryl-3.3-thiodipropionate, ditridecyl-3.3-thiodipropionate, dimyristyl-3.3-thiodipropionate, distearyl-3.3-thiodipropioate. Lauryl stearyl-3.3-thiopropionate, bis [2-methyl-4- (3-n-alkylC12-C14) thiopropionate) -5-t-butylphenyl] sulfide, pentaerythritol tetra (Β-lauryl-thiopropionate) ester, 2-mercaptobenzimidazole, 2-mercapto-6-methylbenzimidazole and the like can be mentioned. One or two or more antioxidants can be simultaneously contained in the photosensitive layer.

  Ultraviolet absorbers include 2- (5-methyl-2-hydroxyphenyl) benzotriazole, 2- [2-hydroxy-3.5-bis (α, α-dimethylbenzyl) phenyl] -2H-benzotriazole, 2- (3.5-di-tert-butyl-2-hydroxyphenyl) benzotriazole, 2- (3-tert-butyl-5-methyl-2-hydroxyphenyl) -5-chlorobenzotriazole, 2- (3.5 -Di-tert-butyl-2-hydroxyphenyl) -5-chlorobenzotriazole, 2- (3.5-di-tert-amyl-2-hydroxyphenyl) benzotriazole, 2- (2'-hydroxy-5 ' -Tert-octylphenyl) benzotriazoles such as benzotriazole, phenyl salicylate, salicylic acid-p-te Salicylic acid systems such as rt-butylphenyl and salicylic acid-p-octylphenyl are preferred. One or more of the above antioxidants can be simultaneously contained in the photosensitive layer.

  The addition amount of the phenolic antioxidant added to the electrophotographic photosensitive member of the present invention is in the range of 3 to 20% by mass with respect to the binder resin, and the addition amount of the amine antioxidant is 3 with respect to the binder resin. The range of ˜20% by mass, and the addition amount of the sulfur-based antioxidant is preferably 0.5 to 5% by mass with respect to the binder resin. On the other hand, it is preferable that the addition amount of a ultraviolet absorber shall be 3-20 mass% with respect to binder resin.

  In addition, a thin film made of an organic thin film such as polyvinyl formal resin, polycarbonate resin, fluororesin, polyurethane resin, or silicone resin, or a siloxane structure formed from a hydrolyzate of a silane coupling agent is formed on the photosensitive layer. A surface protective layer may be provided as a film. In that case, the durability of the photoreceptor is improved, which is preferable. This surface protective layer may be provided in order to improve functions other than the durability improvement.

  As an electrophotographic apparatus on which the electrophotographic photosensitive member of the present invention is mounted, the charging method is usually a contact type such as a brush or a roller, a non-contact type such as a scorotron or a corotron, and any positive or negative charging method. It may be an electric charge. The exposure method may be either LED or LD. The development method may be two-component, one-component, or magnetic / non-magnetic. The transfer method may be either a roller or a belt.

  Next, the electrophotographic apparatus of the present invention will be described. FIG. 4 is a schematic configuration diagram of the electrophotographic apparatus of the present invention. A photoconductor 11 is provided with a charging member 12 in contact therewith. A voltage is supplied from the power source 13 to the charging member. Around the photoreceptor, an exposure device 14, a developing device 15, a transfer device 16, a cleaning device 17, and a static eliminator 18 are provided. Reference numeral 19 denotes a fixing device. FIG. 5 shows an eraseless type electrophotographic apparatus, which has the same structure except that the static eliminator 18 in the electrophotographic apparatus of FIG. 4 is not provided.

Hereinafter, examples of the electrophotographic photosensitive member according to the present invention will be described in detail together with experimental examples and comparative examples.
In the following description, “part” is “part by mass”.

(Synthesis example)
After adding 30 parts of 1,3-diiminoisoindoline and 9.1 parts of gallium trichloride to 230 parts of quinoline and reacting at 200 ° C. for 3 hours, the product was filtered and washed with acetone and methanol. Next, the wet cake was dried to obtain chlorogallium phthalocyanine crystals. This chlorogallium phthalocyanine crystal is dry-ground in an automatic mortar for 3 hours, and further 0.5 part of chlorogallium phthalocyanine is mixed with 60 parts of 1 mmφ glass beads at room temperature in 20 parts of a mixed solvent of water / chlorobenzene 1:10. After ball milling for 24 hours, it was filtered off, washed with 10 parts of methanol and dried to obtain chlorogallium phthalocyanine crystals. This is designated as Pigment 1. The obtained chlorogallium phthalocyanine crystal (Pigment 1) was measured by X-ray diffraction spectrum under the following conditions by powder X-ray diffractometry. As a result, the Bragg angle 2θ with respect to Cu-Kα ray (wavelength 1.542Å) was 7.4 °. 16.6 °, 25.5 °, and 28.3 ° (FIG. 1).

<X-ray diffraction spectrum measurement conditions>
X-ray diffractometer X'Pert manufactured by Flipx Corporation
Measurement conditions X-ray tube Cu
Scanning range 3 ° ~ 40 °
Tube voltage 45kv
Tube current 40mA
Step angle 0.01 degree
Counting time 20 seconds
Receiving slit, divergent slit, variable type
Irradiation width 20mm

(Preparation of electrophotographic photoreceptor)
Alkyd resin (Beckolite M-6401-50 manufactured by Dainippon Ink and Chemicals) and amino resin (Super Becamine G-821-60 manufactured by Dainippon Ink and Chemicals, Inc.) on a cylindrical drum made of uncut aluminum with a diameter of 24 mm. ) In a ratio of 65:35, and the mixed resin and titanium oxide (CR-EL Ishihara Sangyo Co., Ltd.) in a ratio of 1: 3 are dissolved in methyl ethyl ketone to form a coating solution having a film thickness of 1.5 μm. An undercoat layer was formed.

  Next, 10 g of chlorogallium phthalocyanine powder obtained in the synthesis example is added with glass beads and a solution of 10 g of polyvinyl butyral resin (BM-1 manufactured by Sekisui Chemical Co., Ltd.) in 500 ml of 1,3 dioxolane, and a sand mill disperser. After dispersion for 20 hours, the resulting dispersion was filtered to remove the glass beads to prepare a coating solution for charge generation layer. This was dip-coated on the undercoat layer and dried to form a charge generation layer having a thickness of 0.2 μm.

  Next, a polycarbonate resin (Z400 manufactured by Mitsubishi Gas Chemical Company) as a binder resin, a compound represented by the formula [Ia] as a charge transfer agent, and 2.6-di-tert-butyl-4-methyl as an antioxidant Phenol, 2- (2-hydroxy-5-methylphenyl) benzotriazole (Tinuvin-P Geigy) as an ultraviolet absorber was prepared at a mass ratio of 1.0: 1.0: 0.05: 0.05, It melt | dissolved in tetrahydrofuran and prepared the coating liquid for charge transfer layers. The substrate on which the charge generation layer was formed was dip-coated in the charge transfer layer coating solution and dried at 120 ° C. for 60 minutes to form a charge transfer layer having a thickness of 25.0 μm, thereby producing an electrophotographic photosensitive member.

  An electrophotographic photosensitive member was produced in the same manner as in Example 1 except that the charge transfer agent represented by the formula [Ib] was used instead of the charge transfer agent used in Example 1.

  An electrophotographic photosensitive member was produced in the same manner as in Example 1 except that the charge transfer agent represented by the formula [Ic] was used instead of the charge transfer agent used in Example 1.

  An electrophotographic photosensitive member was produced in the same manner as in Example 1 except that the charge transfer agent represented by the formula [Id] was used instead of the charge transfer agent used in Example 1.

  Using the charge generation layer of Example 1, a polycarbonate resin (Z400 manufactured by Mitsubishi Gas Chemical Co., Inc.) as a binder resin, a compound represented by the formula [Ia] as a charge transfer agent, and 2.6-di-dioxide as a phenol-based antioxidant. -Tert-butyl-4-methylphenol, N-phenyl-1-naphthylamine as amine antioxidant, distearyl-3--3-thiodipropionate (Sumilyzer TPS, manufactured by Sumitomo Chemical) UV as sulfur antioxidant 2- (5-Methyl-2-hydroxyphenyl) benzotriazole (Tinvin-P, manufactured by Geigy) as an absorbent, and a mass ratio of 1.0: 1.0: 0.05: 0.05: 0.01: Prepared at 0.05, dissolved in tetrahydrofuran to prepare a charge transfer layer coating solution. The substrate on which the charge generation layer was formed was dip-coated in the charge transfer layer coating solution and dried at 120 ° C. for 60 minutes to form a 25.0 μm charge transfer layer, whereby an electrophotographic photosensitive member was produced.

(Comparative Example 1)
An electrophotographic photosensitive member was produced in the same manner as in Example 1 except that the charge transfer agent represented by the formula [A] was used instead of the charge transfer agent used in Example 1.

(Comparative Example 2)
An electrophotographic photosensitive member was produced in the same manner as in Example 1 except that the charge transfer agent represented by the formula [B] was used instead of the charge transfer agent used in Example 1.

(Comparative Example 3)
An electrophotographic photosensitive member was produced in the same manner as in Example 1 except that Y-type oxytitanium phthalocyanine showing the X-ray diffraction spectrum of FIG. 2 was used instead of the charge generating agent used in Example 1.

(Comparative Example 4)
An electrophotographic photosensitive member was produced in the same manner as in Example 1 except that β-type oxytitanium phthalocyanine having an X-ray diffraction spectrum shown in FIG. 3 was used instead of the charge generating agent used in Example 1.

[Evaluation methods]
The evaluation method is as described below.
Electrostatic characteristics: Using an electrophotographic photosensitive member evaluation apparatus (manufactured by Yamanashi Denshi Kogyo Co., Ltd.), charging, exposing, developing, and transferring the electrophotographic photosensitive member produced according to Examples and Comparative Examples as one cycle, the first cycle The initial potential was measured, and the surface potential (V0) after 10,000 cycles, the residual potential (VL), and the electrostatic characteristics of an exposure amount of 0.6 μJ / cm ² were measured, and the change amount was obtained for evaluation. The results are shown in Table 1.

As is apparent from Table 1, in Examples 1 to 5, the initial charging potential, the residual potential, the charging potential after 10,000 cycles, and the residual potential are greatly changed by the combination of the charge generating agent and the charge transfer agent of the present invention. The photoconductor characteristics were good.
On the other hand, Comparative Examples 1 and 2 are a combination of the charge generating agent used in the present invention and a charge transfer agent other than that used in the present invention. It was not satisfactory as body characteristics. Further, Comparative Examples 3 and 4 are a combination of a charge generating agent other than that used in the present invention and a charge transfer agent used in the present invention, but the residual potential after 10,000 cycles is greatly changed and satisfied with the photoreceptor characteristics. It wasn't possible.

  Photoresponsiveness: Using an electrophotographic photosensitive member evaluation apparatus (manufactured by Yamanashi Denshi Kogyo Co., Ltd.), the electrophotographic photosensitive member produced according to Examples and Comparative Examples is irradiated with a light amount 5 times the half exposure amount and developed from exposure. The surface potential of the electrophotographic photosensitive member at the position of the developing device when the time to reach the developing device was changed was evaluated as photoresponsiveness (−V). The results are shown in Table 2.

As is clear from Table 2, Examples 1 to 5 had excellent photoreceptor characteristics with a low surface potential regardless of whether the time until reaching the developer position after exposure was long or short. On the other hand, in Comparative Examples 1 to 4, the surface potential was remarkably increased when the arrival time was shortened, which was not satisfactory as the photoreceptor characteristics.
In addition, according to the present invention, it is possible to provide a good photoconductor that is excellent in dielectric breakdown resistance against contact charging and does not increase in residual potential.

  The electrophotographic photoreceptor of the present invention has a sensitivity in a long wavelength region, is highly responsive, and has stable electrophotographic characteristics even when used repeatedly at high speed. Therefore, copying that requires miniaturization and high speed is required. It can be suitably used as an electrophotographic photosensitive member for use in a printer or printer device.

The X-ray diffraction pattern of the phthalocyanine composition of this invention is shown. The X-ray diffraction pattern of a Y-type oxytitanium phthalocyanine composition is shown. An X-ray diffraction pattern of β-type oxytitanium phthalocyanine is shown. 1 is a schematic configuration diagram of an electrophotographic apparatus of the present invention. 1 is a schematic configuration diagram of an eraseless electrophotographic apparatus of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Photoconductor 12 Charging member 13 Power supply 14 Exposure apparatus 15 Developing apparatus 16 Transfer apparatus 17 Cleaning apparatus 18 Electric discharger 19 Fixing apparatus

Claims (12)

An electrophotographic photosensitive member in which a photosensitive layer containing at least a charge generating agent, a charge transfer agent, and a binder resin is laminated on a conductive support, wherein the charge generating agent is chlorogallium phthalocyanine, and the charge transfer agent Contains a compound represented by the following general formula [I].

[Wherein R _{1 to} R ₃ each independently represents hydrogen, a halogen atom, an optionally substituted alkyl group having 1 to 6 carbon atoms, or a substituted or unsubstituted aryl having 6 to 12 carbon atoms. Represents a group. ] The electrophotographic photoreceptor according to claim 1, wherein the compound represented by the general formula (I) is a compound represented by the following formula (Ia).

The electrophotographic photoreceptor according to claim 1, wherein the compound represented by the general formula (I) is a compound represented by the following formula (Ib).

The electrophotographic photoreceptor according to claim 1, wherein the compound represented by the general formula (I) is a compound represented by the following formula (Ic).

The electrophotographic photoreceptor according to claim 1, wherein the compound represented by the general formula (I) is a compound represented by the following formula (Id).

  The chlorogallium phthalocyanine has strong diffraction peaks at Bragg angles (2θ ± 0.2 °) of 7.4 °, 16.6 ° 25.5 °, and 28.3 °. The electrophotographic photosensitive member according to any one of the above.   The photosensitive layer includes a charge generation layer containing a charge generation agent formed on a conductive support, and a charge transfer layer containing a charge transfer agent formed on the charge generation layer. Item 7. The electrophotographic photosensitive member according to any one of Items 1 to 6.   8. The electrophotographic photoreceptor according to claim 1, wherein the photosensitive layer contains a hindered phenol antioxidant.   The electrophotographic photosensitive member according to claim 1, wherein the photosensitive layer contains an amine-based antioxidant.   The electrophotographic photosensitive member according to claim 1, wherein the photosensitive layer contains a sulfur-based antioxidant.   The electrophotographic photosensitive member according to claim 1, wherein the photosensitive layer contains a benzotriazole ultraviolet absorber.   In an electrophotographic apparatus that includes a photosensitive member and a charging member to which a voltage is applied so as to be in contact with the photosensitive member, and performs charging, exposure, development, transfer, and static elimination (including cases where there is no static elimination). An electrophotographic apparatus, wherein the photoconductor is the electrophotographic photoconductor according to any one of claims 1 to 11.

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