JP3840161B2 - Electrophotographic photosensitive member, process cartridge and electrophotographic apparatus having electrophotographic photosensitive member, and method of manufacturing electrophotographic photosensitive member - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention is laminated electrophotographic photoreceptor containing an azo pigment and oxytitanium phthalocyanine pigment, a process cartridge and an electrophotographic apparatus having the electrophotographic photosensitive member, and to a manufacturing method of the electrophotographic photosensitive member.
[0002]
[Prior art]
In recent years, electrophotographic photoreceptors used in electrophotographic copying machines, laser printers, and the like have advantages such as high safety, suitability for mass production, and low cost, from organic photoconductor materials. Many formed photoreceptors are used. The organic photoconductor is composed of a single-layer photoconductor having a photosensitive layer mainly composed of a charge generating material, a charge transporting material and a binder resin on a conductive support, and a charge generating material on the conductive support. And a charge generating layer mainly composed of a binder resin, a charge transport material, and a charge transport layer mainly composed of a binder resin. Among them, the laminated type photoconductor can be further improved in sensitivity, and is currently the mainstream of the organic electrophotographic photoconductor.
[0003]
In electrophotographic image formation, digitization of image formation is rapidly progressing in order to obtain high-quality images and to store input images or freely edit them. When digitally forming an image, the digital electrical signal is converted into an optical signal and input to the photoreceptor. As this light source, laser light or LED light is mainly used, and the transmission wavelength of the light source most frequently used at present is 790 ± 20 nm. With the progress of digitalization, the frequency of demand for charge generating materials having sufficient sensitivity in this wavelength region is increasing. A typical charge generation material is a phthalocyanine compound, and among them, many highly sensitive oxytitanium phthalocyanines have been studied. Oxytitanium phthalocyanine is reported in, for example, JP-A-61-239248, JP-A-62-67094, JP-A-1-17066, JP-A-3-54264, and JP-A-3-128973 are being are so many crystal forms known as the oxytitanium phthalocyanine is highly sensitive with a distinct diffraction peak at 27.1 ° of the black grayed angle in X-ray diffraction spectrum (2θ ± 0.2 °) Has been shown to be expensive. In addition, the crystal form is metastable, and when adjusting the dispersion for applying the charge generation layer in the process of producing the photoreceptor, it is easy to change to another stable crystal form depending on the dispersion conditions, and the sensitivity characteristics are impaired. It is easy. Japanese Patent Application Laid-Open No. 6-289628 discloses a method in which a dispersion can be produced while maintaining a stable crystal form by dispersing a oxytitanium phthalocyanine crystal with a solvent containing an equal amount or more of water, thereby achieving high sensitivity. Is disclosed.
[0004]
[Problems to be solved by the invention]
However, since these electrophotographic photoreceptors using oxytitanium phthalocyanine have high sensitivity, a decrease in charging potential or a change in bright portion potential may occur due to repeated image forming processes such as charging, exposure, development and transfer. However, there is a drawback that a kind of memory is generated due to the accumulation of charges in the charge generation layer, and a ghost phenomenon in which a pattern which is not originally present appears on an image occurs.
[0005]
Further, when a paint containing water is applied on the conductive support, image defects due to coating unevenness may occur.
[0006]
Accordingly, it is an object of the present invention to provide an electrophotographic photosensitive member that has high image sensitivity with excellent image quality fluctuations and memory characteristics while maintaining high sensitivity in a laminated electrophotographic photosensitive member using an oxytitanium phthalocyanine pigment. , to provide a process cartridge and an electrophotographic apparatus further having the electrophotographic photosensitive member, and is to provide a manufacturing method of the electrophotographic photosensitive member.
[0007]
[Means for Solving the Problems]
As a result of investigations by the present inventors, charge generation using an oxytitanium phthalocyanine pigment having a clear peak at 27.1 ° with a diffraction angle 2θ ± 0.2 ° in a CuKα characteristic X-ray diffraction spectrum in the charge generation layer When preparing the coating for the layer, the pigment is dispersed with a mixed solvent of water and an organic solvent, the water content in the coating is adjusted to 1 to 3% by mass, and at least one azo pigment is simultaneously contained. As a result, it has been found that image defects due to memory characteristics and coating unevenness can be improved while maintaining high sensitivity, and that potential fluctuation in repeated use can be suppressed to a small level.
[0008]
Although it is not clear why the memory characteristics and potential fluctuations can be kept small, the presence of azo pigment and water in the charge generation layer at the same time makes the carrier (electrons) generated by exposure more than the case of oxytitanium phthalocyanine pigment alone. This may be because recombination and injection into the substrate side can be performed smoothly.
[0009]
That is , the electrophotographic photosensitive member of the present invention is an electrophotographic photosensitive member having a charge generation layer and a charge transport layer on a conductive support, and the charge generation layer is any of the following structural formulas (1) to (5). And an oxytitanium having strong peaks at 9.0 °, 14.2 °, 23.9 ° and 27.1 ° at diffraction angles 2θ ± 0.2 ° in a CuKα characteristic X-ray diffraction spectrum a phthalocyanine pigment, dispersed in a mixed solvent of water and an organic solvent, characterized in that it is a layer formed with a controlled water content to less than 1 wt% to 3 wt% coating.
[0010]
[ Chemical Formula 11 ]
[0011]
[ Chemical formula 12 ]
[0012]
[ Chemical 13 ]
[0013]
[ Chemical formula 14 ]
[0014]
[ Chemical 15 ]
[0015]
The process cartridge of the present invention integrally supports at least one member selected from the group consisting of the electrophotographic photosensitive member and a charging unit, a developing unit, and a cleaning unit, and is detachable from the main body of the electrophotographic apparatus. It is characterized by that.
[0016]
The electrophotographic apparatus of the present invention includes the electrophotographic photosensitive member, a charging unit, an image exposing unit, a developing unit, and a transferring unit.
[0017]
The method for producing an electrophotographic photosensitive member of the present invention is a method for producing an electrophotographic photosensitive member having a charge generation layer and a charge transport layer on a conductive support, and the charge generation layer is represented by the following structural formula (1). To the azo pigment represented by any one of (5) to 9.0 °, 14.2 °, 23.9 ° and 27.1 ° of the diffraction angle 2θ ± 0.2 ° in the CuKα characteristic X-ray diffraction spectrum. An oxytitanium phthalocyanine pigment having a strong peak is dispersed using a mixed solvent of water and an organic solvent, and is formed using a paint having a water content adjusted to 1% by mass or more and less than 3% by mass.
[0018]
[Of 16]
[0019]
[ Chemical formula 17 ]
[0020]
[ Chemical Formula 18 ]
[0021]
[ Chemical formula 19 ]
[0022]
[ Chemical formula 20 ]
[0023]
DETAILED DESCRIPTION OF THE INVENTION
The present invention is described in detail below.
[0024]
The electrophotographic photoreceptor in the present invention is a laminated photoreceptor in which a charge generation layer and a charge transport layer are formed on a conductive support. A typical layer structure is shown in FIG. An example is shown in which the photosensitive layer 1 has a stacked structure of a charge generation layer 2 containing a charge generation material and a charge transport layer 3 containing a charge transport material. Reference numeral 4 denotes a conductive support.
[0025]
The charge generation layer is formed by applying a charge generation paint in which an oxytitanium phthalocyanine pigment and an azo pigment, which are charge generation materials, are dispersed in a binder resin and a dispersion solvent on a conductive support.
[0026]
Oxytitanium phthalocyanine is an oxytitanium phthalocyanine having strong peaks at 9.0 °, 14.2 °, 23.9 ° and 27.1 ° with diffraction angles 2θ ± 0.2 ° in CuKα characteristic X-ray diffraction spectrum . Is represented by the following structural formula.
[0027]
[ Chemical formula 21 ]
[0028]
The measurement of X-ray diffraction in the present invention was performed using CuKα rays under the following conditions.
Measuring instrument used: Fully automatic X-ray diffractometer MXP18, manufactured by Mac Science
X-ray tube: Cu
Tube voltage: 50 kV
Tube current: 300mA
Scan method: 2θ / θ scan Scan speed: 4 deg. / Min
Sampling interval: 0.020 deg.
Start angle (θ): 3 deg.
Stop angle (θ): 40 deg.
Divergence slit: 0.5 deg.
Scattering slit: 0.5 deg.
Receiving slit: 0.3mm
Use curved monochromator 【0029】
The azo pigment, those having a high sensitivity to the wavelength of the electrophotographic device mounted light sources, preferably in maintaining high sensitivity, is shown by any one of the following structural formulas (1) to (5) Used .
[0030]
[ Chemical Formula 22 ]
[0031]
[ Chemical Formula 23 ]
[0032]
[ Chemical formula 24 ]
[0033]
[ Chemical formula 25 ]
[0034]
[ Chemical formula 26 ]
[0035]
The ratio of the oxytitanium phthalocyanine pigment to the azo pigment is preferably in the range of 99/1 to 50/50.
[0036]
When mixing the charge generation material in forming the charge generation layer, each material is dispersed in an appropriate binder resin and solvent at a ratio within the above range, or the individually dispersed liquid is set to a predetermined ratio. Mix. When dispersed individually, the binder resin and the solvent may be different from each other.
[0037]
Examples of the binder resin include polyamide resin, polyvinyl butyral resin, polyester resin, acrylic resin, polycarbonate resin, polyvinyl acetal resin, polystyrene resin, polyarylate resin, polyvinyl benzal resin, polyurethane, epoxy resin, and phenol resin. . Ratio of the pigment to the binder resin is at 10 mass ratio: 1 to 1: 5, preferably 5: 1 to 1: in the range of 4. Further, it is preferable that the concentration of the pigment in the dispersion liquid is in the range of 0.5 to 10% by mass in view of the efficiency of dispersion and post-treatment.
[0038]
The dispersion solvent may be a mixed solvent of an organic solvent and water, but the amount of water added during dispersion is preferably 1% by mass or more and less than 100% by mass with respect to the pigment.
[0039]
The organic solvent is preferably a hydrophilic one, for example, ether solvents such as tetrahydrofuran, n-propyl ether, n-butyl ether and 1,4-dioxane, alcohol solvents such as ethanol, propanol and 2-methoxyethanol, acetone, Examples thereof include ketone solvents such as methyl ethyl ketone and cyclohexanone.
[0040]
The dispersion treatment can be performed using, for example, a milling device such as a paint shaker, a sand mill, or a ball mill, a homogenizer, an ultrasonic dispersion or a high-pressure liquid collision dispersion device, etc. together with dispersion media such as glass beads, steel beads, and alumina balls. It is preferable to disperse the pigment until the dispersed particle diameter is 0.5 μm or less, and more preferably 0.2 μm or less, in order to suppress image defects such as popping and fogging.
[0041]
The dispersion after dispersion may be used as a coating solution for the charge generation layer and the concentration may be adjusted with an organic solvent or a mixed solvent of an organic solvent and water, but the solid content concentration during coating is 0. 0.5 to 5.0% by mass is preferable , and 1 to 4% by mass is particularly preferable. Moreover, it adjusts so that the moisture content in a coating material may be 1 mass% or more and less than 3 mass%. If the water content is less than 1% by mass, the memory characteristics cannot be improved sufficiently, and if it is 3% by mass or more, image defects such as spots and unevenness occur when the paint is applied on the conductive support. Resulting in.
[0042]
Furthermore, you may add an additive etc. in a coating material.
[0043]
The thickness of the charge generation layer is preferably in the range of 0.05 to 5 μm.
[0044]
The conductive support used in the present invention may be any conductive support as long as it has conductivity, for example, a metal such as aluminum, copper, chromium, nickel, zinc, and stainless steel formed into a drum or sheet, aluminum Metal foil such as copper or copper laminated on plastic film, aluminum, indium oxide, tin oxide etc. deposited on plastic film, metal or plastic with conductive layer applied alone or with binder resin A film, paper, etc. are mentioned.
[0045]
In addition, when the image input is laser light, such as a laser beam printer, a conductive layer may be provided on the support for the purpose of preventing interference fringes due to scattering or covering a scratch on the substrate. This can be formed by dispersing conductive powder such as carbon black and metal particles in a binder resin. The film thickness of the conductive layer is 5 to 40 μm, preferably 10 to 30 μm.
[0046]
Furthermore, an undercoat layer can be provided on the conductive support or on the conductive layer. The undercoat layer can be formed of polyamide, polyvinyl alcohol, polyethylene oxide, casein, ethyl cellulose, polyurethane, polyether urethane, or the like. The thickness of the undercoat layer is 0.05 to 5 μm, preferably 0.3 to 1 μm.
[0047]
The charge transport layer is composed of a charge transport material and a binder resin. Examples of the charge transport material include triarylamine compounds, hydrazone compounds, stilbene compounds, pyrazoline compounds, oxazole compounds, triallylmethane compounds, thiazole compounds, and the like.
[0048]
As binder resin, aromatic polyester resin such as polycarbonate and polyarylate, saturated alkyl polyester resin, polymethacrylate, acrylic resin such as styrene-acrylic copolymer, polystyrene, styrene-butadiene rubber, ethylene-vinyl acetate copolymer, acetic acid Examples thereof include vinyl and copolymers thereof, polyethylene terephthalate resin, polybutylene terephthalate resin, polyacetal, polyether sulfone, polysulfone, polyphenylene sulfide, polyether ketone, silicone resin, acrylic resin, and polyurethane resin. The binder resin may have a charge transport function.
[0049]
The thickness of the charge transport layer is 5 to 40 μm, preferably 10 to 35 μm.
[0050]
Further, a protective layer can be provided on the photosensitive layer for protecting the surface of the photoreceptor. Binder resins that can be used for the protective layer include polycarbonate resin, polyester resin, polyarylate resin, polystyrene resin, polyethylene resin, polypropylene resin, polyurethane resin, acrylic resin, epoxy resin, silicone resin, cellulose resin, and polyvinyl chloride resin. Phosphazene resin, melamine resin, vinyl chloride-vinyl acetate copolymer, and the like. In the protective layer, metal, metal oxide, carbon black, or the like may be dispersed as conductive particles. Examples of the metal include aluminum, zinc, copper, chromium, nickel, stainless steel, and silver, or those obtained by depositing these metals on the surface of plastic particles. Examples of the metal oxide include zinc oxide, titanium oxide, tin oxide, antimony oxide, indium oxide, bismuth oxide, tin-doped indium oxide, antimony-doped tin oxide, and antimony-doped zirconium oxide. These can be used alone or in combination of two or more.
[0051]
The film thickness suitable for the protective layer is 0.2 to 10 μm, more preferably 0.5 to 6 μm.
[0052]
In addition, in order to improve durability in the charge transport layer and the protective layer, inorganic fillers, polyethylene, polyfluoroethylene, silica and the like as lubricants, dispersants as additives, ultraviolet absorbers and antioxidants, silicone oil, A leveling agent or the like may be added.
[0053]
As a coating method for coating each layer, a dip coating method, a spray coating method, a roll coater coating method, and a gravure coating method can be used.
[0054]
Next, an electrophotographic apparatus using the electrophotographic photosensitive member of the present invention will be described.
[0055]
FIG. 2 shows a schematic configuration of an electrophotographic apparatus provided with a process cartridge having the electrophotographic photosensitive member of the present invention.
[0056]
In FIG. 2, reference numeral 11 denotes a drum-shaped electrophotographic photosensitive member of the present invention, which is rotationally driven around a shaft 12 in the direction of an arrow at a predetermined peripheral speed. In the rotation process, the electrophotographic photosensitive member 11 is uniformly charged at a predetermined positive or negative potential on its peripheral surface by the primary charging unit 13, and then from an exposure unit (not shown) such as slit exposure or laser beam scanning exposure. The exposure light 14 that is enhanced and modulated corresponding to the time-series electric digital image signal of the target image information to be output is received. In this way, electrostatic latent images corresponding to target image information are sequentially formed on the peripheral surface of the electrophotographic photosensitive member 11.
[0057]
The formed electrostatic latent image is then developed with toner by the developing means 15 and taken out from a paper feeding unit (not shown) between the electrophotographic photosensitive member 11 and the transfer means 16 in synchronization with the rotation of the electrophotographic photosensitive member 11. The toner image formed and supported on the surface of the electrophotographic photosensitive member 11 is sequentially transferred by the transfer unit 16 to the transferred transfer material 17.
[0058]
The transfer material 17 that has received the transfer of the toner image is separated from the surface of the electrophotographic photosensitive member, introduced into the image fixing means 18, and subjected to image fixing to be printed out as an image formed product (print, copy). .
[0059]
The surface of the electrophotographic photosensitive member 11 after the image transfer is cleaned by the cleaning means 19 after the transfer residual toner is removed, and used repeatedly for image formation.
[0060]
In the present invention, among the above-described electrophotographic photosensitive member 11 and primary charging means 13, developing means 15, cleaning means 19 and the like, a plurality of them are housed in a container and integrally combined as a process cartridge. The process cartridge may be configured to be detachable from an electrophotographic apparatus main body such as a copying machine or a laser beam printer. For example, at least one of the primary charging unit 13, the developing unit 15, and the cleaning unit 19 is integrally supported together with the electrophotographic photosensitive member 11 to form a cartridge, and is attached to and detached from the apparatus main body using a guide unit 22 such as a rail of the apparatus main body. A flexible process cartridge 21 can be obtained.
[0061]
Further, when the electrophotographic apparatus is a copying machine or a printer, the exposure light 14 is a reflected light or transmitted light from a document, or a signal is read by a document by a sensor, and a laser beam scanning performed according to this signal is performed. The light emitted by driving the LED array or the liquid crystal shutter array.
[0062]
The electrophotographic photoreceptor of the present invention can be used not only in electrophotographic copying machines but also widely in electrophotographic application fields such as laser beam printers, CRT printers, LED printers, FAX, liquid crystal printers, and laser plate making. .
[0063]
【Example】
Examples of the present invention will be described below. In the examples, “part” means part by mass.
[0064]
Example 1
Apply an aluminum cylinder having a diameter of 30 mm and a length of 260 mm as a support, and sequentially apply a coating composed of the following materials onto the support in the order of a conductive layer, an undercoat layer, a charge generation layer, and a charge transport layer. A photoconductor was prepared.
[0065]
As conductive layer paint
Conductive pigment: SnO ₂ coated barium sulfate 10 parts Resistance adjusting pigment: Titanium oxide 2 parts Binder resin: Phenol resin 6 parts Leveling agent: Silicone oil 0.001 part Solvent: Methanol / methoxypropanol = 0.2 / 0. 8 20 parts were dispersed for 2 hours in a sand mill apparatus containing 1 mmφ glass beads to prepare. This paint was applied on a support by a dipping method and thermally cured at 140 ° C. for 30 minutes to form a conductive layer having a thickness of 15 μm.
[0066]
Next, a solution prepared by dissolving 5 parts of N-methoxymethylated nylon and 1 part of copolymer nylon in a mixed solvent of 65 parts of methanol and 30 parts of n-butanol was applied on this by a dipping method. A pulling layer was formed.
[0067]
The charge generation paint was adjusted as follows. As a charge generation material, an oxytitanium phthalocyanine pigment 11 having strong peaks at 9.0 °, 14.2 °, 23.9 °, and 27.1 ° of diffraction angles 2θ ± 0.2 ° in an X-ray diffraction spectrum of CuKα parts, azo Pigments 4 parts represented by the following structural formula (1), polyvinyl butyral (trade name BX-1, Sekisui Chemical Co., Ltd.) 10 parts, special grade tetrahydrofuran 294 parts as dispersion solvent, and distilled water 6 parts Each was dispersed for 8 hours at 20 ° C. in a sand mill apparatus using 400 parts of 1 mmφ glass beads (GB201M, manufactured by Toshiba Ballotini Co., Ltd.). The obtained dispersion was diluted with 300 parts of special grade cyclohexanone to prepare a coating solution. It was 1.1 mass% when the moisture content of the obtained coating liquid was measured with the Karl Fischer measuring device (AQV-200, made by Hiranuma Sangyo).
[0068]
[ Chemical 27 ]
[0069]
This paint was applied onto the undercoat layer by a dipping method and dried at 80 ° C. for 10 minutes to form a charge generation layer having a thickness of 0.2 μm.
[0070]
The charge transport coating was adjusted as follows. First, in order to prepare a fluororesin particle dispersion,
Bisphenol Z-type polycarbonate (trade name: Z-800, manufactured by Mitsubishi Gas Chemical) 2 parts tetrafluoroethylene resin fine particles (Lublon L-2, manufactured by Daikin Industries, Ltd.) 2 parts Fluorine-based comb-type graft polymer (trade name GF300) Toa Gosei Chemical Co., Ltd.) 0.06 part Monochlorobenzene 20 parts after thoroughly mixing, then dispersed in a sand grinder (made by Imex Co., Ltd.) using glass beads, 4-fluoroethylene resin particles A dispersion was prepared. 9 parts of a compound represented by the following structural formula as a charge transport material,
[0071]
[ Chemical formula 28 ]
[0072]
1 part of a compound represented by the structural formula
[0073]
[Of 29]
[0074]
8 parts of bisphenol Z-type polycarbonate (trade name: Z-800, manufactured by Mitsubishi Gas Chemical) and 24 parts of the 4-fluoroethylene resin particle dispersion were dissolved in a mixed solution of 40 parts of dichloromethane and 60 parts of monochlorobenzene. This solution was applied onto the charge generation layer by a dip coating method and dried at 115 ° C. for 60 minutes to form a charge transport layer having a thickness of 30 μm, thereby producing an electrophotographic photoreceptor.
[0075]
The electrophotographic photosensitive member thus produced was evaluated by an apparatus in which an image exposure apparatus of a printer Laser Jet 4000 manufactured by Hewlett-Packard Co., Ltd. was modified so that the amount of light could be changed. The produced electrophotographic photosensitive member is charged with this apparatus so that the dark part potential (Vd) becomes −700 V, and this is irradiated with laser light having a wavelength of 780 nm, so that the bright part potential (Vl) becomes −150 V. The required amount of light was measured and used as sensitivity. The surface potential of the electrophotographic photosensitive member was measured by removing the developing cartridge from the evaluator and inserting a potential measuring device there. The potential measuring device is configured by arranging a potential measuring probe at the developing position of the developing cartridge, and the position of the potential measuring probe with respect to the electrophotographic photosensitive member is substantially at the center in the drum axis direction, with a gap from the drum surface. It was 3 mm. Further, an endurance of 10,000 sheets is performed in an intermittent mode in which an image with a printing ratio of 6% is stopped once for each print in an atmosphere of 23 ° C./55% RH, and a potential difference ΔVd (= Vd after endurance of 10,000 sheets-initial Vd) and ΔVl (= Vl after endurance of 10,000 sheets-initial Vl) were obtained.
[0076]
Moreover, image evaluation was performed as follows. First, an image with an appropriate pattern and then the entire halftone is output on the first circumference of the electrophotographic photosensitive member, and the presence or absence of the first pattern (ghost) in the halftone and the halftone unevenness are visually confirmed. did. In addition, a solid black image was output to check for the presence of image defects such as white spots. The results are shown in Table 1.
[0077]
(Example 2)
In the formation of the charge generation layer of Example 1, electrons were obtained in the same manner as in Example 1 except that 7.5 parts of the oxytitanium phthalocyanine pigment and 7.5 parts of the azo pigment represented by the structural formula (1) were used. Photoconductors were prepared and evaluated. The results are shown in Table 1.
[0078]
Example 3
In formation of the charge generation layer in Example 1, 3 parts of azo Pigments represented by 11 parts of oxytitanium phthalocyanine pigment, the above structural formula used in Example 1 (1), represented by the following structural formula (2) addition to the 1 part of azo Pigments is to produce the electrophotographic photosensitive member in the same manner as in example 1 and evaluated. The results are shown in Table 1.
[0079]
[ Chemical 30 ]
[0080]
Example 4
An electrophotographic photoreceptor was prepared and evaluated in the same manner as in Example 1 except that the azo pigment contained in the charge generation layer was replaced with an azo pigment represented by the following structural formula (3) . The results are shown in Table 1.
[0081]
[ Chemical 31 ]
[0082]
(Example 5)
An electrophotographic photoreceptor was prepared and evaluated in the same manner as in Example 1 except that the azo pigment contained in the charge generation layer was replaced with an azo pigment represented by the following structural formula (4) . The results are shown in Table 1.
[0083]
[ Chemical Formula 32 ]
[0084]
(Example 6)
An electrophotographic photoreceptor was prepared and evaluated in the same manner as in Example 1 except that the azo pigment contained in the charge generation layer was replaced with an azo pigment represented by the following structural formula (5) . The results are shown in Table 1.
[0085]
[ Chemical Formula 33 ]
[0086]
(Example 7)
In the charge generation layer coating material of Example 1, an electrophotographic photosensitive member was produced and evaluated in the same manner as in Example 1 except that the production method was changed as follows.
[0087]
10 parts of an oxytitanium phthalocyanine pigment having strong peaks at 9.0 °, 14.2 °, 23.9 °, and 27.1 ° at diffraction angles 2θ ± 0.2 ° in the X-ray diffraction spectrum of CuKα, polyvinyl butyral ( 10 parts of product name BX-1, Sekisui Chemical Co., Ltd., 192 parts of special grade tetrahydrofuran and 8 parts of distilled water as dispersion solvents, each using 300 parts of 1 mmφ glass beads (GB201M, manufactured by Toshiba Barotini Co., Ltd.) The dispersion was carried out with an apparatus at 20 ° C. for 4 hours. Azo Pigment 5 parts to be subsequently represented by the structural formula (1) used in Example 1, a special grade of tetrahydrofuran 96 parts of distilled water 4 parts of a dispersion solvent, 1 mm in diameter glass beads (GB201M, manufactured by Toshiba Ballotini Co.) In another sand mill apparatus using 200 parts, the dispersion was performed at 20 ° C. for 20 hours. The obtained dispersion was mixed and diluted with 300 parts of special grade cyclohexanone to prepare a coating solution. It was 2.1 mass% when the moisture content of the obtained coating liquid was measured with the Karl Fischer measuring device (AQV-200, made by Hiranuma Sangyo).
[0088]
(Example 8)
An electrophotographic photoreceptor was prepared and evaluated in the same manner as in Example 1 except that in the charge generation layer coating material of Example 1, the dispersion was changed to 290 parts of cyclohexanone and 10 parts of distilled water.
[0089]
The water content of the charge generation layer coating at this time was 2.8% by mass.
[0090]
(Comparative Example 1)
An electrophotographic photoreceptor was prepared and evaluated in the same manner as in Example 1 except that the azo pigment was not used in the charge generation layer of Example 1.
[0091]
(Comparative Example 2)
An electrophotographic photosensitive member was prepared and evaluated in the same manner as in Example 1 except that the azo pigment was not used in the charge generation layer of Example 1 and the dispersion solvent was changed to 300 parts of special grade tetrahydrofuran. The water content of the charge generation layer coating at this time was 0.3% by mass, and the crystal form of the dispersed oxytitanium phthalocyanine pigment was changed to the crystal form shown in X-ray crystal form spectrum FIG.
[0092]
(Comparative Example 3)
Oxytitanium phthalocyanine pigment contained in the charge generation layer having strong peaks at 7.6 ° and 28.6 ° of diffraction angle 2θ ± 0.2 ° in the X-ray diffraction spectrum of CuKα (X-ray diffraction spectrum diagram 5) An electrophotographic photosensitive member was prepared and evaluated in the same manner as in Example 1 except that it was replaced with. The results are shown in Table 1.
[0093]
(Comparative Example 4)
An electrophotographic photoreceptor was prepared and evaluated in the same manner as in Example 1 except that in the charge generation layer of Example 1, the dispersion solvent was changed to 282 parts of special grade tetrahydrofuran and 18 parts of distilled water.
[0094]
The water content of the charge generation layer coating at this time was 3.0% by mass.
[0095]
(Comparative Example 5)
An electrophotographic photosensitive member was prepared and evaluated in the same manner as in Example 1 except that the dispersion solvent was changed to 300 parts of special grade tetrahydrofuran in the charge generation layer coating material of Example 1.
[0096]
The water content of the charge generation layer coating at this time was 0.3% by mass.
[0097]
[Table 1]
[0098]
【The invention's effect】
As described above, according to the present invention, an electrophotographic photosensitive member having high sensitivity, small potential fluctuation in repeated use, and few image defects due to memory characteristics and coating unevenness, and an electrophotographic apparatus and process having the electrophotographic photosensitive member. A cartridge and a method for producing an electrophotographic photosensitive member can be provided.
[Brief description of the drawings]
FIG. 1 is a diagram showing a layer structure of an electrophotographic photosensitive member of the present invention.
FIG. 2 is a diagram illustrating an example of a schematic configuration of an electrophotographic apparatus including a process cartridge having the electrophotographic photosensitive member of the present invention.
FIG. 3 is a characteristic X-ray diffraction pattern of oxytitanium phthalocyanine according to an embodiment of the present invention.
FIG. 4 is a characteristic X-ray diffraction pattern of oxytitanium phthalocyanine of Comparative Example of the present invention.
FIG. 5 is a characteristic X-ray diffraction pattern of oxytitanium phthalocyanine of Comparative Example of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Photosensitive layer 2 Charge generating layer 3 Charge transport layer 4 Conductive support 11 Electrophotographic photosensitive member 12 Shaft 13 Charging means 14 Exposure light 15 Developing means 16 Transfer means 17 Transfer material 18 Fixing means 19 Cleaning means 21 Process cartridge 22 Guide means

Claims (4)

In an electrophotographic photosensitive member having a charge generation layer and a charge transport layer on a conductive support,
The charge generation layer comprises an azo pigment represented by any of the following structural formulas (1) to (5) , 9.0 ° with a diffraction angle 2θ ± 0.2 ° in a CuKα characteristic X-ray diffraction spectrum , 14.2 °, and oxytitanium phthalocyanine pigment having strong peaks at 23.9 ° and 27.1 °, dispersed in a mixed solvent of water and an organic solvent, to adjust the moisture content to less than 1 wt% to 3 wt% coating An electrophotographic photosensitive member, wherein the electrophotographic photosensitive member is a layer formed using
The electrophotographic photosensitive member according to claim 1, as well, that the charging means, at least one means selected from the group consisting of developing hand Dan及 beauty cleaning means integrally supported, is detachable to the main body of the electrophotographic apparatus Process cartridge characterized by. The electrophotographic photosensitive member according to claim 1, charging means, an electrophotographic apparatus, comprising a developing hand Dan及 beauty transfer means. In the method for producing an electrophotographic photoreceptor having a charge generation layer and a charge transport layer on a conductive support,
The charge generation layer is composed of an azo pigment represented by any one of the following structural formulas (1) to (5), 9.0 ° with a diffraction angle 2θ ± 0.2 ° in a CuKα characteristic X-ray diffraction spectrum, 14.2 An oxytitanium phthalocyanine pigment having strong peaks at °, 23.9 °, and 27.1 ° is dispersed in a mixed solvent of water and an organic solvent, and the water content is adjusted to 1% by mass or more and less than 3% by mass. Form using
A method for producing an electrophotographic photosensitive member.