JP2005266503A - Image forming apparatus and process cartridge - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus which can stably obtain excellent image quality for a long period of time even when a spherical toner is used as a developer and also can achieve higher image quality and reduction of a load on an environment at high level, and to provide a process cartridge. <P>SOLUTION: This image forming apparatus is equipped with an electrophotographic photoreceptor, a charging device, an exposing device, a developing device, and a transfer device; and the electrophotographic photoreceptor has a conductive base and a photosensitive layer which is provided on the conductive base and contains hydroxy gallium phthalocyanine having a maximum peak wavelength within a range of 810 to 839 nm in a spectral absorption spectrum in a wavelength range of 600 to 900 nm, and the developing device supplies a toner of 100 to 140 in mean shape coefficient to the electrophographic photoreceptor and develops an electrostatic latent image to form a toner image on the electrophotographic photoreceptor. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an electrophotographic image forming apparatus and a process cartridge.

  An electrophotographic image forming apparatus is an apparatus that forms an image by performing an image forming cycle including processes such as charging, exposure, development, and transfer using an electrophotographic photosensitive member, and has high speed and high print quality. Since it has the advantage of being obtained, it is widely used in the fields of copying machines, laser beam printers, and the like.

As a developer used in such an image forming apparatus, a toner whose shape is controlled to a spherical shape or a specific shape has been used instead of an irregularly shaped toner that has been conventionally used (for example, (See Patent Document 1). Spherical toner is expected as a developer capable of obtaining a high-quality output image due to its excellent shape uniformity. In addition, the use of spherical toner is considered preferable from the viewpoint of environmental conservation because the transfer efficiency is improved and the amount of discarded toner can be reduced.
JP 2001-305797 A

  However, when spherical toner is used in an actual image forming process, there is a problem that a small amount of untransferred toner remaining on the surface of the electrophotographic photosensitive member after the transfer process is difficult to be removed (cleaned).

  As a method for cleaning the untransferred toner, for example, there is a method (cleaning blade method) in which a cleaning blade such as an elastic rubber blade is scraped against the surface of the electrophotographic photosensitive member. However, in order to clean the spherical toner by the cleaning blade method, it is necessary to set the contact pressure of the cleaning member to the surface of the electrophotographic photosensitive member higher than that of the irregular toner, and the surface of the electrophotographic photosensitive member or the cleaning blade The load of increases. Accordingly, when the image forming apparatus is used for a long period of time, phenomena such as abrasion of the surface of the electrophotographic photosensitive member, chipping of the cleaning blade, and turning up tend to occur. Further, toner filming may occur in which untransferred toner that has passed through the cleaning blade is deposited on the electrophotographic photosensitive member to form a film. In addition, when the electrophotographic photosensitive member is worn due to the use of the spherical toner, the electric field strength applied to the electrophotographic photosensitive member is increased, fogging, and further, the exposure history in the previous image forming cycle becomes the next image forming cycle. Image quality defects such as appearing ghosts are likely to occur.

  Therefore, in the conventional image forming apparatus, in order to avoid the above-described phenomenon, it is necessary to keep the degree of spheroidization low so that the spherical toner does not become a true sphere as much as possible, thereby improving image quality and reducing the burden on the environment. There is still room for improvement to achieve this.

  The present invention has been made in view of such a situation, and even when a spherical toner is used as a developer, good image quality can be stably obtained over a long period of time. An object of the present invention is to provide an image forming apparatus and a process cartridge capable of achieving a reduction in load at a high level.

  As a result of intensive studies to achieve the above-mentioned problems, the present inventors used hydroxygallium phthalocyanine exhibiting specific spectral absorption characteristics as a charge generation material contained in the photosensitive layer of the electrophotographic photoreceptor, The present inventors have found that the above problems can be solved by using a toner whose average spherical coefficient satisfies a specific condition as a developer, and have completed the present invention.

  That is, the image forming apparatus of the present invention is provided on the conductive support and the conductive support, and has a maximum peak wavelength in the range of 810 to 839 nm in the spectral absorption spectrum in the wavelength range of 600 to 900 nm. An electrophotographic photosensitive member having a photosensitive layer containing hydroxygallium phthalocyanine, a charging device for charging the electrophotographic photosensitive member, an exposure device for exposing the charged electrophotographic photosensitive member to form an electrostatic latent image, and A toner having an average shape factor of 100 to 140 is supplied to the electrophotographic photosensitive member, and the electrostatic latent image is developed to form a toner image on the electrophotographic photosensitive member, and the toner image is covered from the electrophotographic photosensitive member. And a transfer device for transferring to a transfer medium.

  The average shape factor (ML2 / A) referred to in the present invention is an index of the degree of spheroidization of toner particles, and means a value calculated by the following formula. In the case of a true sphere, ML2 / A = 100. When determining the average shape factor, the toner particles are observed with an optical microscope, the data is taken into an image analyzer (for example, LUZEXIII, manufactured by Nireco), the equivalent circle diameter is measured, and the maximum length and area are individually measured. ML2 / A can be obtained for the particles. Here, the maximum length means the maximum length of the projected image formed when the toner is projected on the plane when the toner is projected by the parallel light incident perpendicularly to the plane. The area means the area of this projection image.

ML2 / A = (maximum length of particle) ² × π × 100 / (area × 4)
The transfer medium referred to in the present invention means a medium for transferring a toner image formed on the electrophotographic photoreceptor, and an image output medium such as paper on which the toner image from the electrophotographic photoreceptor is directly transferred. Further, an intermediate transfer member in an intermediate transfer type image forming apparatus is included.

  As described above, by combining the electrophotographic photosensitive member containing the specific hydroxygallium phthalocyanine in the photosensitive layer with the developing device for supplying the specific toner to the electrophotographic photosensitive member, a good image quality can be stably maintained over a long period of time. Therefore, it is possible to achieve high image quality and reduction of environmental load at a high level.

  The reason why the above effect can be obtained by the image forming apparatus of the present invention is not necessarily clear, but the present inventors infer as follows.

  In general, in the case of a phthalocyanine pigment, since the interaction between molecules differs depending on the crystal structure (molecular arrangement in the crystal), the difference is reflected in the spectral absorption spectrum. For example, V-type hydroxygallium phthalocyanine known as a conventional charge generation material has an absorption maximum at 840 to 870 nm in the spectral absorption spectrum in the wavelength range of 600 to 900 nm, which indicates the presence of strong intermolecular interactions. Suggests. Such a charge generating substance tends to cause fogging due to an increase in dark current because electric charges easily flow in the crystal. In addition, since there are many places (sites) where charges can exist in the crystal, when charges flow into the photosensitive layer from the transfer medium, the charges are easily trapped at the sites. Furthermore, a part of the charge generated in the photosensitive layer is trapped in the site by the exposure in the previous image forming cycle. As a result, there are many charges (free carriers) in the photosensitive layer, and there is a difference in exposure potential between the exposed area and the unexposed area in the previous image forming cycle, which becomes a ghost in the next image forming cycle. It is guessed that it appears.

  On the other hand, the hydroxygallium phthalocyanine used in the present invention has a maximum peak wavelength at 810 to 839 nm in a spectral absorption spectrum in a wavelength region of 600 to 900 nm. Such spectral absorption spectrum suggests that the intermolecular interaction is small compared to conventional charge generation materials, the charge does not flow excessively in the crystal, and the number of trap sites present in the crystal is It is thought that it has been sufficiently reduced. Further, the hydroxygallium phthalocyanine is considered to be excellent in dispersibility as compared with conventional charge generating materials. Therefore, it is presumed that generation of fog and ghost can be sufficiently suppressed by incorporating such hydroxygallium phthalocyanine in the photosensitive layer of the electrophotographic photosensitive member.

  In the present invention, it is preferable that the maximum primary particle diameter of hydroxygallium phthalocyanine is 0.3 μm or less. By using hydroxygallium phthalocyanine whose primary particle diameter satisfies the above conditions, it is possible to achieve higher levels of prevention of fogging and ghosting and improvement of transfer efficiency.

  In the present invention, hydroxygallium phthalocyanine has diffraction peaks at Bragg angles (2θ ± 0.2 °) of 7.5 ° and 28.3 ° in an X-ray diffraction spectrum using CuKα characteristic X-rays. It is preferable. By using such hydroxygallium phthalocyanine, prevention of fog and ghost and improvement of transfer efficiency can be achieved at a higher level.

  In the present invention, the electrophotographic photoreceptor preferably further has an undercoat layer between the conductive support and the photosensitive layer, and the undercoat layer preferably contains inorganic fine particles.

  In the present invention, it is preferable that the maximum peak in the range of 600 to 700 nm is larger than the maximum peak in the range of 810 to 839 nm in the spectral absorption spectrum of the photosensitive layer.

  The process cartridge of the present invention is provided on the conductive support and the conductive support, and has a maximum peak wavelength in the range of 810 to 839 nm in the spectral absorption spectrum in the wavelength range of 600 to 900 nm. An electrophotographic photosensitive member having a photosensitive layer containing hydroxygallium phthalocyanine, and a developing device capable of supplying toner having an average shape factor of 100 to 140 to the electrophotographic photosensitive member.

  According to the present invention, even when spherical toner is used as a developer, good image quality can be stably obtained over a long period of time, and high image quality and reduction of environmental load can be achieved at a high level. Possible image forming apparatuses and process cartridges are provided.

  Hereinafter, preferred embodiments of the present invention will be described in detail.

    Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings.

  First, the electrophotographic photoreceptor provided in the image forming apparatus of the present invention will be described in detail. 1 to 4 are schematic cross-sectional views showing preferred examples of the electrophotographic photosensitive member according to the present invention. The electrophotographic photosensitive member 1 is a plane perpendicular to the stacking direction of the conductive substrate 2 and the photosensitive layer 3. It has been cut. The electrophotographic photoreceptors 1 shown in FIGS. 1 to 4 are all function-separated photoreceptors, and the charge generation layer 5 and the charge transport layer 6 are separately provided in the photosensitive layer 3 provided in each photoreceptor. . More specifically, in the electrophotographic photoreceptor 1 shown in FIG. 1, a charge generation layer 5 and a charge transport layer 6 are laminated in this order on a conductive substrate 2 to form a photosensitive layer 3. In the electrophotographic photoreceptor 1 shown in FIG. 3, the undercoat layer 4, the charge generation layer 5 and the charge transport layer 6 are laminated in this order on the conductive substrate 2 to form the photoreceptor 3. In the illustrated electrophotographic photoreceptor 1, a photosensitive layer 3 is formed by laminating an undercoat layer 4, a charge generation layer 5, a charge transport layer 6 and a protective layer 7 in this order on a conductive substrate 2. In the electrophotographic photoreceptor 1 shown in FIG. 4, the undercoat layer 4, the intermediate layer 8, the charge generation layer 5, and the charge transport layer 6 are laminated in this order on the conductive substrate 2 to form the photosensitive layer 3. ing. In each of the electrophotographic photoreceptors 1 shown in FIGS. 1 to 4, the charge generation layer 5 contains hydroxygallium phthalocyanine having a maximum peak wavelength in the range of 810 to 839 nm in the spectral absorption spectrum in the wavelength range of 600 to 900 nm. It consists of Although not shown here, the present invention can also be applied to a single-layer type photoreceptor having a single photosensitive layer. The electrophotographic photosensitive member shown in FIGS. 1 to 4 is a preferred example according to the present invention, and the present invention is not limited thereto.

  Hereinafter, each component of the electrophotographic photoreceptor 1 will be described in detail.

  The conductive substrate 2 is made of a metal such as aluminum, copper, iron, zinc or nickel; on a substrate such as a sheet, paper, plastic or glass, aluminum, copper, gold, silver, platinum, palladium, titanium, nickel-chromium , Stainless steel, copper-indium and other metals deposited; conductive metal compounds such as indium oxide and tin oxide deposited on the substrate; metal foil laminated on the substrate; carbon black, indium oxide, Examples include tin oxide-antimony oxide powder, metal powder, copper iodide and the like dispersed in a binder resin and applied to the substrate to conduct a conductive treatment. The shape of the conductive substrate 2 may be any of a drum shape, a sheet shape, and a plate shape.

  Further, when a metal pipe base is used as the conductive base 2, the surface of the pipe base may be a raw pipe, but the surface of the base is roughened by a surface treatment in advance. Is also possible. Such roughening can prevent grain-like density spots due to interference light that can be generated inside the photosensitive member when a coherent light source such as a laser beam is used as the exposure light source. Examples of the surface treatment include mirror cutting, etching, anodizing, rough cutting, centerless grinding, sand blasting, wet honing and the like.

  Materials used for the undercoat layer 4 include: zirconium chelate compounds, zirconium alkoxide compounds, zirconium coupling agents and other organic zirconium compounds; titanium chelate compounds, titanium alkoxide compounds, titanate coupling agents and other organic titanium compounds; aluminum chelate compounds Organoaluminum compounds such as aluminum coupling agents; antimony alkoxide compounds; germanium alkoxide compounds; organic indium compounds such as indium alkoxide compounds and indium chelate compounds; organic manganese compounds such as manganese alkoxide compounds and manganese chelate compounds; tin alkoxide compounds and Suzuki Organotin compounds such as rate compounds; Aluminum silicon alkoxide compounds; Kokishido compounds; aluminum zirconium alkoxide compounds include organometallic compounds such as. Among these, organic zirconium compounds, organic titanyl compounds, and organoaluminum compounds are preferably used because of their low residual potential and good electrophotographic characteristics.

  The undercoat layer 4 includes vinyltrichlorosilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris-2-methoxyethoxysilane, vinyltriacetoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-methacryloxy. Propyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-chloropropyltrimethoxysilane, γ-2-aminoethylaminopropyltrimethoxysilane, γ-mercapropropyltrimethoxysilane, γ-ureidopropyltriethoxysilane, It can be used by containing a silane coupling agent such as β-3,4-epoxycyclohexyltrimethoxysilane. Furthermore, polyvinyl alcohol, polyvinyl methyl ether, poly-N-vinylimidazole, polyethylene oxide, ethyl cellulose, methyl cellulose, ethylene-acrylic acid copolymer, polyamide, polyimide, casein, gelatin, polyethylene, polyester, phenol resin, vinyl chloride- Known binder resins such as a vinyl acetate copolymer, an epoxy resin, polyvinyl pyrrolidone, polyvinyl pyridine, polyurethane, polyglutamic acid, and polyacrylic acid can also be used. These mixing ratios can be appropriately set as necessary.

  It is also possible to include inorganic fine particles in the undercoat layer 4. As the inorganic fine particles, metal oxide fine particles are preferable. The metal oxide fine particles can be arbitrarily selected from known metal oxides as long as the desired electrophotographic photoreceptor characteristics can be obtained, but one or more metals selected from tin oxide, titanium oxide, and zinc oxide Oxide fine particles are preferably used. The metal oxide fine particles are more preferably coated with at least one coupling agent, and the coupling agent is more preferably a silane coupling agent.

In the undercoat layer 4, an electron transport pigment can also be mixed / dispersed. Examples of electron transport pigments include organic pigments such as perylene pigments, bisbenzimidazole perylene pigments, polycyclic quinone pigments, indigo pigments, and quinacridone pigments, and electron-withdrawing pigments such as cyano groups, nitro groups, nitroso groups, and halogen atoms. Examples thereof include organic pigments such as bisazo pigments and phthalocyanine pigments having a substituent, and inorganic pigments such as zinc oxide and titanium oxide. Among these pigments, perylene pigments, bisbenzimidazole perylene pigments and polycyclic quinone pigments are preferably used because of their high electron mobility. If the amount of the electron transporting pigment is too large, the strength of the undercoat layer is lowered and a coating film defect is caused.
The undercoat layer 4 is formed by applying a coating solution obtained by mixing / dispersing the above materials in a predetermined organic solvent on the substrate 2 and removing the solvent by drying. Examples of the mixing / dispersing method in preparing the coating solution for the undercoat layer include a ball mill, a roll mill, a sand mill, an attritor, and an ultrasonic wave. As the organic solvent, any solvent can be used as long as it does not cause gelation or aggregation when a periodical metal compound or resin is dissolved and an electron transporting pigment is mixed / dispersed. Specifically, methanol, ethanol, n-propanol, n-butanol, benzyl alcohol, methyl cellosolve, ethyl cellosolve, acetone, methyl ethyl ketone, cyclohexanone, methyl acetate, n-butyl acetate, dioxane, tetrahydrofuran, methylene chloride, chloroform , Chlorobenzene, toluene and the like, and these can be used alone or in admixture of two or more. The coating solution is dried at a temperature at which the solvent can be evaporated and a film can be formed. The thickness of the undercoat layer 4 thus obtained is preferably 0.1 to 10 μm, and more preferably 0.5 to 5.0 μm when it does not contain metal oxide fine particles. . Moreover, when it contains metal oxide microparticles | fine-particles, it is preferable to exceed 15 micrometers, and it is more preferable that it is 15-50 micrometers. When the thickness of the undercoat layer 4 satisfies the above conditions, local dielectric breakdown (photoreceptor leakage) in the electrophotographic photoreceptor can be more reliably prevented. In addition, stable characteristics can be obtained even in long-term continuous use.

  The material used for the intermediate layer 8 is the same as the material used for the undercoat layer 4, such as a zirconium chelate compound, a zirconium alkoxide compound, a zirconium coupling agent, etc .; a titanium chelate compound, a titanium alkoxide compound, a titanate cup Organic titanium compounds such as ring agents; Aluminum chelate compounds; Organoaluminum compounds such as aluminum coupling agents; Antimony alkoxide compounds; Germanium alkoxide compounds; Organic indium compounds such as indium alkoxide compounds and indium chelate compounds; Manganese alkoxide compounds and manganese chelates Organic manganese compounds such as compounds; Organotin compounds such as tin alkoxide compounds and tin chelate compounds; Aluminum silicon Al Kishido compounds; aluminum titanium alkoxide compound; aluminum zirconium alkoxide compounds include organometallic compounds such as. Among these, organic zirconium compounds, organic titanyl compounds, and organoaluminum compounds are preferably used because of their low residual potential and good electrophotographic characteristics.

  Further, like the undercoat layer 4, the intermediate layer 8 includes vinyltrichlorosilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris-2-methoxyethoxysilane, vinyltriacetoxysilane, γ-glycidoxypropyltri Methoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-chloropropyltrimethoxysilane, γ-2-aminoethylaminopropyltrimethoxysilane, γ-mercapropropyltrimethoxysilane, γ -A silane coupling agent such as ureidopropyltriethoxysilane or β-3,4-epoxycyclohexyltrimethoxysilane can be contained and used. Furthermore, polyvinyl alcohol, polyvinyl methyl ether, poly-N-vinylimidazole, polyethylene oxide, ethyl cellulose, methyl cellulose, ethylene-acrylic acid copolymer, polyamide, polyimide, casein, gelatin, polyethylene, polyester, phenol resin, vinyl chloride- Known binder resins such as a vinyl acetate copolymer, an epoxy resin, polyvinyl pyrrolidone, polyvinyl pyridine, polyurethane, polyglutamic acid, and polyacrylic acid can also be used. These mixing ratios can be appropriately set as necessary.

  Further, in the intermediate layer 8, similarly to the undercoat layer 4, an electron transporting pigment can be mixed / dispersed and used. Examples of electron transport pigments include organic pigments such as perylene pigments, bisbenzimidazole perylene pigments, polycyclic quinone pigments, indigo pigments, and quinacridone pigments, and electron-withdrawing pigments such as cyano groups, nitro groups, nitroso groups, and halogen atoms. Examples thereof include organic pigments such as bisazo pigments and phthalocyanine pigments having a substituent, and inorganic pigments such as zinc oxide and titanium oxide. Among these pigments, perylene pigments, bisbenzimidazole perylene pigments and polycyclic quinone pigments are preferably used because of their high electron mobility. If the amount of the electron transporting pigment is too large, the strength of the undercoat layer is lowered and a coating film defect is caused.

  Similarly to the undercoat layer 4, the intermediate layer 8 is formed by applying a coating solution obtained by mixing / dispersing the above materials in a predetermined organic solvent onto the substrate 2 and removing the solvent by drying. Examples of the mixing / dispersing method in preparing the coating solution for the undercoat layer include a ball mill, a roll mill, a sand mill, an attritor, and an ultrasonic wave. As the organic solvent, any solvent can be used as long as it does not cause gelation or aggregation when a periodical metal compound or resin is dissolved and an electron transporting pigment is mixed / dispersed. Specifically, methanol, ethanol, n-propanol, n-butanol, benzyl alcohol, methyl cellosolve, ethyl cellosolve, acetone, methyl ethyl ketone, cyclohexanone, methyl acetate, n-butyl acetate, dioxane, tetrahydrofuran, methylene chloride, chloroform , Chlorobenzene, toluene and the like, and these can be used alone or in admixture of two or more. The coating solution is dried at a temperature at which the solvent can be evaporated and a film can be formed. The thickness of the intermediate layer 8 thus obtained is preferably 0.1 to 10 μm, and more preferably 0.5 to 5 μm. When the film thickness of the intermediate layer 8 satisfies the above conditions, stable characteristics can be obtained even when the electrophotographic photosensitive member is used continuously for a long time.

  The charge generation layer 5 contains hydroxygallium phthalocyanine having a maximum peak wavelength in the range of 810 to 839 nm in the spectral absorption spectrum in the wavelength range of 600 to 900 nm, and a binder resin.

  As described above, the hydroxygallium phthalocyanine used in the present invention has a maximum peak wavelength in the range of 810 to 839 nm (preferably 810 to 835 nm) in the spectral absorption spectrum in the wavelength range of 600 to 900 nm. Hydroxygallium phthalocyanine exhibiting such a spectral absorption spectrum has a smaller intermolecular interaction and a smaller number of charge trap sites present in the crystal than conventional hydroxygallium phthalocyanine. Therefore, by using such a hydroxygallium phthalocyanine as a charge generating substance, it is possible to sufficiently suppress the occurrence of fog caused by the proposed current due to the intermolecular interaction and the ghost caused by the charge trapped at the site.

  In the spectral absorption spectrum of the charge generation layer 5 containing the specific hydroxygallium phthalocyanine, the maximum peak in the range of 600 to 700 nm is in the range of 810 to 839 nm from the viewpoint of dispersibility of hydroxygallium phthalocyanine. It is preferably larger than the maximum peak at.

  Moreover, it is preferable that the hydroxygallium phthalocyanine used in the present invention does not contain coarse particles having a large particle size. Specifically, it is preferable not to contain coarse particles having a primary particle diameter exceeding 0.3 μm, and it is more preferable not to include coarse particles exceeding 0.2 μm. When the primary particle diameter exceeds 0.3 μm, the particles are coarsened or the aggregates of the particles are formed, leading to an increase in dark current and an increase in trap sites. And ghosts are likely to occur.

  Further, the hydroxygallium phthalocyanine pigment used in the present invention preferably has diffraction peaks at 7.5 ° and 28.3 ° of the Bragg angle (2θ ± 0.2 °) with respect to the CuKα characteristic X-ray.

  An example of a method for producing hydroxygallium phthalocyanine used as a charge generation material in the present invention is shown below.

  First, a method of reacting o-phthalodinitrile or 1,3-diiminoisoindoline and gallium trichloride in a predetermined solvent (type I chlorogallium phthalocyanine method); o-phthalodinitrile, alkoxygallium and ethylene glycol Crude gallium phthalocyanine is produced by a method of synthesizing a phthalocyanine dimer (phthalocyanine dimer) by reacting with heating in a predetermined solvent (phthalocyanine dimer method). As the solvent in the above reaction, α-chloronaphthalene, β-chloronaphthalene, α-methylnaphthalene, methoxynaphthalene, dimethylaminoethanol, diphenylethane, ethylene glycol, dialkyl ether, quinoline, sulfolane, dichlorobenzene, dimethylformamide, dimethyl It is preferable to use an inert and high boiling point solvent such as sulfoxide or dimethylsulfamide.

  Next, the crude gallium phthalocyanine obtained in the above step is subjected to an acid pasting process, whereby the crude gallium phthalocyanine is made into fine particles and converted into I-type hydroxygallium phthalocyanine. Here, the acid pasting treatment is, specifically, a solution in which crude gallium phthalocyanine is dissolved in an acid such as sulfuric acid or an acid salt such as a sulfate is poured into an aqueous alkaline solution, water or ice water, Recrystallized. As the acid used for the acid pasting treatment, sulfuric acid is preferable, and sulfuric acid having a concentration of 70 to 100% (particularly preferably 95 to 100%) is more preferable.

  In the method for producing a hydroxygallium phthalocyanine pigment of the present invention, the I-type hydroxygallium phthalocyanine obtained by the acid pasting treatment is wet-pulverized with a solvent to refine the crystal while converting the crystal.

  Here, the wet pulverization treatment is performed using a pulverizer using a spherical medium having an outer diameter of 0.1 to 3.0 mm, preferably a spherical medium having an outer diameter of 0.2 to 2.5 mm. Is done using. When the outer shape of the media is larger than 3.0 mm, the pulverization efficiency is lowered, so that the particle diameter does not become small and aggregates tend to be easily generated. Further, when the outer diameter of the medium is smaller than 0.1 mm, it tends to be difficult to separate the medium and the hydroxygallium phthalocyanine pigment. In addition, when the media is not spherical, but in other shapes such as a columnar shape or an indefinite shape, the grinding efficiency is reduced and the media is easily worn by grinding, so that the wear powder becomes an impurity and deteriorates the characteristics of the hydroxygallium phthalocyanine pigment. There is a tendency to make it easy.

  The material of the media is not particularly limited, but is preferably one that hardly causes image quality defects even when mixed in a hydroxygallium phthalocyanine pigment, and glass, zirconia, alumina, meno and the like are preferable.

  Further, the material of the container for performing the wet pulverization treatment is not particularly limited, but it is preferable that it does not easily cause image quality defects when mixed in a hydroxygallium phthalocyanine pigment, and glass, zirconia, alumina, meno, polypropylene, poly Tetrafluoroethylene, polyphenylene sulfide and the like are preferable. Alternatively, the inner surface of a metal container such as iron or stainless steel may be lined with glass, polypropylene, polytetrafluoroethylene, polyphenylene sulfide, or the like.

  The amount of the media used varies depending on the apparatus used, but is 50 parts by weight or more, preferably 55 to 100 parts by weight, based on 1 part by weight of the type I hydroxygallium phthalocyanine pigment. Also, as the media outer diameter decreases, the media density in the device increases even with the same weight (use amount), and the viscosity of the mixed solution increases and the pulverization efficiency changes. It is desirable to perform wet processing at an optimal mixing ratio by controlling the amount of media used and the amount of solvent used.

  In the wet pulverization treatment, the amount of the solvent used is 5 to 50 parts by weight, preferably 10 to 30 parts by weight, based on 1 part by weight of the I-type hydroxygallium phthalocyanine.

  Moreover, the temperature of the wet pulverization treatment is preferably 0 to 100 ° C, more preferably 5 to 80 ° C, and particularly preferably 10 to 50 ° C. When the temperature is low, the rate of crystal transition tends to be slow, and when the temperature is too high, the solubility of the hydroxygallium phthalocyanine pigment tends to be high and crystal growth tends to be difficult. is there.

  Examples of the solvent used in the wet grinding treatment include amides such as N, N-dimethylformamide, N, N-dimethylacetamide, and N-methylpyrrolidone; esters such as ethyl acetate, n-butyl acetate, and iso-amyl acetate. In addition to ketones such as acetone, methyl ethyl ketone, methyl iso-butyl ketone, dimethyl sulfoxide and the like. The amount of these solvents used is usually 1 to 200 parts by weight, preferably 1 to 100 parts by weight, based on 1 part by weight of the hydroxygallium phthalocyanine pigment.

  As an apparatus used for the wet pulverization treatment, an apparatus using a media such as a vibration mill, an automatic mortar, a sand mill, a dyno mill, a coball mill, an attritor, a planetary ball mill, or a ball mill as a dispersion medium can be used.

  The speed of atomization and crystal conversion of the phthalocyanine pigment in the wet pulverization process is greatly affected by the scale of the wet pulverization, the stirring speed, the media material, etc. In the production method of the present invention, the following method is used. Determine wet grinding time.

  The crystal conversion state is monitored by measuring the absorption wavelength of the wet pulverization treatment liquid so that the hydroxygallium phthalocyanine pigment after the wet pulverization treatment has a maximum peak wavelength in the range of 810 to 839 nm in the spectral absorption spectrum in the wavelength range of 600 to 900 nm. However, it is preferable to determine the wet pulverization time while continuing the crystal conversion into the hydroxygallium phthalocyanine pigment. Here, as a method for monitoring the crystal conversion state by measuring the absorption wavelength of the wet pulverization treatment liquid, for example, a small amount of the pigment solution during the crystal conversion treatment is sampled from a wet pulverization treatment apparatus and diluted with a solvent such as acetone or ethyl acetate. Examples include a method of measuring the prepared solution by a liquid cell method using a spectrophotometer, and a method of measuring the BET specific surface area by washing and drying the pigment.

  The wet pulverization time thus determined is usually in the range of 5 to 500 hours, preferably in the range of 7 to 300 hours. When the treatment time is less than 5 hours, the crystal conversion is not completed, and the electrophotographic characteristics are deteriorated, and particularly, the sensitivity is apt to be insufficient. Further, when the processing time exceeds 500 hours, sensitivity tends to decrease due to the influence of pulverization stress, productivity decreases, and media wear powder tends to be mixed. By determining the wet pulverization time as described above, it is possible to complete the wet pulverization process in a state where the hydroxygallium phthalocyanine pigment particles are uniformly finely divided, and furthermore, a plurality of lots of repeated wet pulverization processes were performed. In this case, it is possible to suppress the quality variation between lots.

  In the present invention, as long as the position of the absorption peak of hydroxygallium phthalocyanine is maintained within a predetermined range, it is possible to subject the hydroxygallium phthalocyanine to surface treatment in order to improve dispersibility. A coupling agent or the like can be used as the surface treatment agent, but is not limited thereto. As coupling agents, vinyltrimethoxysilane, γ-methacryloxypropyl-tris (β-methoxyethoxy) silane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane , Vinyltriacetoxysilane, γ-mercaptopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, N-β- (aminoethyl) -γ-aminopropyltrimethoxysilane, N-β- (aminoethyl) -γ- Examples include silane coupling agents such as aminopropylmethylmethoxysilane, N, N-bis (β-hydroxyethyl) -γ-aminopropyltriethoxysilane, and γ-chloropropyltrimethoxysilane. Among these, vinyltriethoxysilane, vinyltris (2-methoxyethoxysilane), 3-methacryloxypropyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxy Silane, N-2- (aminoethyl) -3-aminopropyltrimethoxysilane, N-2- (aminoethyl) -3-aminopropylmethyldimethoxysilane, 3-aminopropyltriethoxysilane, N-phenyl-3- Aminopropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, and 3-chloropropyltrimethoxysilane are preferred.

  In addition to coupling agents, zirconium butoxide, zirconium zirconium acetoacetate, zirconium triethanolamine, acetylacetonate zirconium butoxide, ethyl acetoacetate butoxide, zirconium acetate, zirconium oxalate, zirconium lactate, zirconium phosphonate, zirconium octoate An organic zirconium compound such as zirconium naphthenate, zirconium laurate, zirconium stearate, zirconium isostearate, methacrylate zirconium butoxide, stearate zirconium butoxide, or isostearate zirconium butoxide may be blended. Tetraisopropyl titanate, tetranormal butyl titanate, butyl titanate dimer, tetra (2-ethylhexyl) titanate, titanium acetylacetonate, polytitanium acetylacetonate, titanium octylene glycolate, titanium lactate ammonium salt, titanium lactate, titanium lactate Organic titanium compounds such as ethyl ester, titanium triethanolamate, polyhydroxytitanium stearate, aluminum isopropylate, monobutoxy aluminum diisopropylate, aluminum butyrate, diethyl acetoacetate aluminum diisopropylate, aluminum tris (ethyl acetoacetate) An organoaluminum compound such as can also be used.

  In the charge generation layer 5, the specific hydroxygallium phthalocyanine is dispersed and held in a predetermined binder resin. Such a binder resin can be selected from a wide range of insulating resins. Preferred binder resins include polyvinyl acetal resin, polyarylate resin, polycarbonate resin, polyester resin, phenoxy resin, vinyl chloride-vinyl acetate copolymer, polyamide resin, acrylic resin, polyacrylamide resin, polyvinyl pyridine resin, cellulose resin, Examples thereof include insulating resins such as urethane resin, epoxy resin, casein, polyvinyl alcohol resin, and polyvinylpyrrolidone resin, and organic photoconductive polymers such as poly-N-vinyl carbazole, polyvinyl anthracene, polyvinyl pyrene, and polysilane. Among these, polyvinyl acetal resin and vinyl chloride-vinyl acetate copolymer are preferably used. These binder resins can be used alone or in combination of two or more. The blending ratio (weight ratio) between the charge generating material and the binder resin is preferably in the range of 10: 1 to 1:10, and more preferably in the range of 8: 2 to 3: 7.

  When the charge generation layer 5 is formed, a coating solution in which the hydroxygallium phthalocyanine is dispersed in a solution in which a binder resin is dissolved in a predetermined organic solvent is used. As an organic solvent for the coating solution for the charge generation layer, a solvent capable of dissolving the binder resin, for example, alcohol, aromatic, halogenated hydrocarbon, ketone, ketone alcohol, ether, ester, etc. Can be used. More specifically, methanol, ethanol, n-propanol, iso-propanol, n-butanol, benzyl alcohol, methyl cellosolve, ethyl cellosolve, acetone, methyl ethyl ketone, cyclohexanone, methyl acetate, ethyl acetate, n-butyl acetate, Examples include dioxane, tetrahydrofuran, methylene chloride, chloroform, chlorobenzene, toluene and the like. These solvents can be used alone or in combination of two or more. Examples of a method for dispersing the hydroxygallium phthalocyanine pigment in the binder resin liquid include a ball mill, a roll mill, a sand mill, an attritor, and an ultrasonic wave.

  In addition, various additives may be added to the charge generation layer 5 in order to improve the electrical characteristics and the image quality as long as the position of the absorption maximum of hydroxygallium phthalocyanine is maintained within a predetermined range. Additives include quinone compounds such as chloranil, bromoanil and anthraquinone, tetracyanoquinodimethane compounds, fluorenones such as 2,4,7-trinitrofluorenone and 2,4,5,7-tetranitro-9-fluorenone Compound, 2- (4-biphenyl) -5- (4-t-butylphenyl) -1,3,4-oxadiazole, 2,5-bis (4-naphthyl) -1,3,4-oxadi Azoles, oxadiazole compounds such as 2,5-bis (4-diethylaminophenyl) -1,3,4-oxadiazole, xanthone compounds, thiophene compounds, 3,3 ′, 5,5′-tetra- Electron transport materials such as diphenoquinone compounds such as t-butyldiphenoquinone, electron transport pigments such as polycyclic condensation systems and azo systems, zirconium chelate compounds, Hexafluorophosphate chelate compounds, aluminum chelate compounds, titanium alkoxide compounds, organic titanium compounds, can be used a silane coupling agent or the like.

  Examples of silane coupling agents include vinyltrimethoxysilane, γ-methacryloxypropyl-tris (β-methoxyethoxy) silane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ-glycidoxypropyl. Trimethoxysilane, vinyltriacetoxysilane, γ-mercaptopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, N-β- (aminoethyl) -γ-aminopropyltrimethoxysilane, N-β- (aminoethyl) -Γ-aminopropylmethylmethoxysilane, N, N-bis (β-hydroxyethyl) -γ-aminopropyltriethoxysilane, γ-chloropropyltrimethoxysilane, and the like.

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

  Examples of titanium chelate compounds include tetraisopropyl titanate, tetranormal butyl titanate, butyl titanate dimer, tetra (2-ethylhexyl) titanate, titanium acetylacetonate, polytitanium acetylacetonate, titanium octylene glycolate, titanium lactate ammonium salt , Titanium lactate, titanium lactate ethyl ester, titanium triethanolamate, polyhydroxy titanium stearate and the like.

  Examples of the aluminum chelate compound include aluminum isopropylate, monobutoxy aluminum diisopropylate, aluminum butyrate, diethyl acetoacetate aluminum diisopropylate, aluminum tris (ethyl acetoacetate) and the like.

  These compounds may be used individually by 1 type, and may be used as a mixture or polycondensate of 2 or more types of compounds.

  The charge transport layer 6 includes a charge transport material and a binder resin. Specific examples of such charge transport materials include oxadiazole derivatives such as 2,5-bis (p-diethylaminophenyl) -1,3,4-oxadiazole, 1,3,5-triphenylpyrazoline. 1- [pyridyl- (2)]-3- (p-diethylaminostyryl) -5- (p-diethylaminostyryl) pyrazoline and other pyrazoline derivatives, triphenylamine, tri (p-methyl) phenylamine, N, N Aromatic tertiary such as' -bis (3,4-dimethylphenyl) biphenyl-4-amine, dibenzylaniline, 9,9-dimethyl-N, N'-di (p-tolyl) fluoren-2-amine Aromatic tertiary dia such as amino compounds, N, N′-diphenyl N, N′-bis (3-methylphenyl)-[1,1′-biphenyl] -4,4′-diamine Compounds, 1,2,4-triazine derivatives such as 3- (4′-dimethylaminophenyl) -5,6-di- (4′-methoxyphenyl) -1,2,4-triazine, 4-diethylaminobenzaldehyde Hydrazone derivatives such as -1,1-diphenylhydrazone, 4-diphenylaminobenzaldehyde-1,1-diphenylhydrazone, [p- (diethylamino) phenyl]-(1-naphthyl) -phenylhydrazone, 2-phenyl-4-styryl Quinazoline derivatives such as quinazoline, benzofuran derivatives such as 6-hydroxy-2,3-di (p-methoxyphenyl) benzofuran, α-stilbene such as p- (2,2-diphenylvinyl) -N, N′-diphenylaniline Derivatives, enamine derivatives, carbazole derivatives such as N-ethylcarbazole , A hole transport material poly -N- vinylcarbazole and derivatives thereof. In addition, quinone compounds such as chloranil, bromoanil, anthraquinone, tetracyanoquinodimethane compounds, fluorenone compounds such as 2,4,7-trinitrofluorenone, 2,4,5,7-tetranitro-9-fluorenone, 2 -(4-biphenyl) -5- (4-t-butylphenyl) -1,3,4-oxadiazole, 2,5-bis (4-naphthyl) -1,3,4-oxadiazole, 2 Oxadiazole compounds such as 1,5-bis (4-diethylaminophenyl) -1,3,4-oxadiazole, xanthone compounds, thiophene compounds, 3,3 ′, 5,5′-tetra-t-butyl Electron transport materials such as diphenoquinone compounds such as diphenoquinone can also be used. Furthermore, a polymer having a group composed of the above compound in the main chain or side chain can also be used. These charge transport materials can be used alone or in combination of two or more.

  The binder resin for the charge transport layer 6 is preferably a resin capable of forming an electrical insulating film. Examples of such resins include polycarbonate resin, polyarylate resin, polyester resin, methacrylic resin, acrylic resin, polyvinyl chloride resin, polyvinylidene chloride resin, polystyrene resin, polyvinyl acetate resin, styrene-butadiene copolymer, chloride Vinylidene-acrylonitrile copolymer, vinyl chloride-vinyl acetate copolymer, vinyl chloride-vinyl acetate-maleic anhydride copolymer, silicone resin, silicon-alkyd resin, phenol-formaldehyde resin, styrene-alkyd resin, poly-N -Carbazole, polyvinyl butyral, polyvinyl formal, polysulfone, casein, gelatin, polyvinyl alcohol, ethyl cellulose, phenol resin, polyamide, carboxy-methyl cellulose, Fluoride polymer waxes, polyurethanes and the like. Among these, the polycarbonate resin having a structural unit represented by the following general formula (I-1) and the polyarylate resin having a structural unit represented by the following general formula (I-2) are: It is excellent in compatibility, solubility in a solvent, and strength, and is preferably used.

[Wherein R ^{1 to} R ⁸ may be the same or different and each represents a hydrogen atom, an alkyl group, an allyl group, an aralkyl group, a substituted or unsubstituted aryl group, or a halogen atom, and X is substituted or unsubstituted. An alkylene group, a substituted or unsubstituted cycloalkylene group or a substituted or unsubstituted arylene group, and n represents an integer. ]

[Wherein, R ^{1 to} R ⁸ may be the same or different and each represents a hydrogen atom, an alkyl group, an allyl group, an aralkyl group, a substituted or unsubstituted aryl group, or a halogen atom, and X and Y may be the same. Each may be different, and each represents a substituted or unsubstituted alkylene group, a substituted or unsubstituted cycloalkylene group, or a substituted or unsubstituted arylene group, and n represents an integer. ]
These binder resins can be used individually by 1 type or in mixture of 2 or more types. The mixing ratio (weight ratio) between the binder resin and the charge transport material can be arbitrarily set in any case, but attention must be paid to a decrease in electrical characteristics and a decrease in film strength.

  The charge transport layer 6 is formed by applying a charge transport layer coating liquid containing the above material onto the charge generation layer 5 and drying it. The solvent used in the coating solution can be arbitrarily selected from known organic solvents as long as the desired electrophotographic photoreceptor characteristics can be obtained, but dioxane, tetrahydrofuran, methylene chloride, chloroform, chlorobenzene, toluene and the like are preferable. Used for. Moreover, these can be used individually by 1 type or in mixture of 2 or more types. The thickness of the charge transport layer 6 is preferably 5 to 50 μm, more preferably 10 to 40 μm.

  In the charge transport layer 6, additives such as an antioxidant and a light stabilizer are added to the photosensitive layer for the purpose of preventing deterioration of the photoreceptor due to ozone, oxidizing gas, or light / heat generated in the image forming apparatus. Can be added.

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

  Examples of phenolic antioxidants include 2,6-di-t-butyl-4-methylphenol, styrenated phenol, n-octadecyl-3- (3 ′, 5′-di-t-butyl-4′-hydroxy Phenyl) -propionate, 2,2′-methylene-bis- (4-methyl-6-tert-butylphenol), 2-t-butyl-6- (3′-tert-butyl-5′-methyl-2′-) Hydroxybenzyl) -4-methylphenyl acrylate, 4,4′-butylidene-bis- (3-methyl-6-tert-butylphenol), 4,4′-thio-bis- (3-methyl-6-tert-butylphenol) ), 1,3,5-tris (4-t-butyl-3-hydroxy-2,6-dimethylbenzyl) isocyanurate, tetrakis- [methylene-3- (3 ′, 5 ′,-di-t-butyl) − 4′-hydroxyphenyl) propionate] methane, 3,9-bis [2- [3- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionyloxy] -1,1-dimethylethyl] -2 4,8,10-tetraoxaspiro [5,5] undecane and the like.

  Examples of hindered amine compounds include bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate, bis (1,2,2,6,6-pentamethyl-4-piperidyl) sebacate, 1- [2- [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionyloxy] ethyl] -4- [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionyloxy]- 2,2,6,6-tetramethylpiperidine, 8-benzyl-7,7,9,9-tetramethyl-3-octyl-1,3,8-triazaspiro [4,5] undecane-2,4-dione 4-benzoyloxy-2,2,6,6-tetramethylpiperidine, dimethyl-1- (2-hydroxyethyl) -4-hydroxy-2,2,6,6-tetramethylpiperidine succinate Polycondensate, poly [{6- (1,1,3,3-tetramethylbutyl) imino-1,3,5-triazine-2,4-diimyl} {(2,2,6,6-tetra Methyl-4-piperidyl) imino} hexamethylene {(2,3,6,6-tetramethyl-4-piperidyl) imino}], 2- (3,5-di-t-butyl-4-hydroxybenzyl)- 2-n-butylmalonate bis (1,2,2,6,6-pentamethyl-4-piperidyl), N, N′-bis (3-aminopropyl) ethylenediamine-2,4-bis [N-butyl- N- (1,2,2,6,6-pentamethyl-4-piperidyl) amino] -6-chloro-1,3,5-triazine condensate and the like.

  Examples of organic sulfur antioxidants include dilauryl-3,3′-thiodipropionate, dimyristyl-3,3′-thiodipropionate, distearyl-3,3′-thiodipropionate, pentaerythritol-tetrakis. -(Β-laurylthiopropionate), ditridecyl-3,3′-thiodipropionate, 2-mercaptobenzimidazole and the like.

  Examples of the organophosphorus antioxidant include trisnonylphenyl phosfte, triphenyl phosfte, tris (2,4-di-t-butylphenyl) -phosfte, and the like.

The organic sulfur-based and organic phosphorus-based antioxidants are called secondary antioxidants, and a synergistic effect can be obtained by using them together with a primary antioxidant such as a phenol-based or amine-based antioxidant.
Examples of the light stabilizer include benzophenone, benzotriazole, dithiocarbamate, and tetramethylpiperidine derivatives.

  Examples of the benzophenone light stabilizer include 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-octoxybenzophenone, 2,2'-dihydroxy-4-methoxybenzophenone, and the like.

  Examples of the benzotriazole light stabilizer include 2- (2′-hydroxy-5′-methylphenyl) -benzotriazole, 2- [2′-hydroxy-3 ′-(3 ″, 4 ″, 5 ′, 6 ″). -Tetrahydrophthalimido-methyl) -5'-methylphenyl] benzotriazole, 2- (2'-hydroxy-3'-t-butyl-5'-methylphenyl) -5-chlorobenzotriazole, 2- (2'- Hydroxy-3′-t-butyl-5′-methylphenyl) -5-chlorobenzotriazole, 2- (2′-hydroxy-3 ′, 5 ′,-di-t-butylphenyl) benzotriazole, 2- ( 2'-hydroxy-5'-t-octylphenyl) benzotriazole, 2- (2'-hydroxy-3 ', 5',-di-t-amylphenyl) benzotriazole And the like.

  Examples of other compounds include 2,4-di-t-butylphenyl-3 ', 5'-di-t-butyl-4'-hydroxybenzoate and nickel dibutyl-dithiocarbamate.

In addition, at least one electron-accepting substance can be included for the purpose of improving sensitivity, reducing residual potential, and reducing fatigue during repeated use. Examples of electron accepting substances include succinic anhydride, maleic anhydride, dibromomaleic anhydride, phthalic anhydride, tetrabromophthalic anhydride, tetracyanoethylene, tetracyanoquinodimethane, o-dinitrobenzene, m-dinitrobenzene, Examples include chloranilquinone, dinitroanthraquinone, trinitrofluorenone, picric acid, o-nitrobenzoic acid, p-nitrobenzoic acid, and phthalic acid. Among these, fluorenone compounds, quinone compounds and, Cl-, CN-, NO 2 _- benzene derivatives having an electron attractive substituent, and the like are particularly preferable.

  The charge transport layer 6 can be dispersed with organic resin fine particles and metal oxide for the purpose of reducing wear. Organic resin fine particles include fluorine-containing resin particles (tetrafluoroethylene, trifluoroethylene, hexafluoropropylene resin, vinyl fluoride resin, vinylidene fluoride resin, ethylene difluoride diethylene chloride, and copolymers thereof) ), Silicon-containing resin particles, and the like. Among these organic resin fine particles, ethylene tetrafluoride resin and vinylidene fluoride resin are particularly preferable. Examples of the metal oxide include silica, alumina, titanium oxide, tin oxide and the like. When the organic resin fine particles are dispersed, the friction coefficient on the surface of the charge transport layer is reduced, so that wear can be suppressed. Further, when the metal oxide is dispersed, the mechanical hardness of the charge transport layer is increased, so that wear can be suppressed. Further, since the fluorine-containing resin particles are hardly dispersed particles, dispersibility is improved by using a fluorine-containing polymer-based dispersion aid. As a method for dispersing the organic resin fine particles and the metal oxide, methods such as a roll mill, a ball mill, a vibration ball mill, an attritor, a sand mill, a colloid mill, a paint shaker, a homogenizer, and a high-pressure treatment type homogenizer can be used. In this dispersion, it is effective to make the dispersed particles 1.0 μm or less, preferably 0.5 μm or less.

  Further, a trace amount of silicone oil can be added as a leveling agent for improving the smoothness of the coating film.

  In the present invention, as shown in FIG. 3, the protective layer 7 can be formed as necessary. As the protective layer 7, the cured film formed including the compound represented by the following general formula (II) is preferable.

F [-D-SiR ⁹ _3-a (OR ¹⁰ ) _a ] _b (II)
In general formula (II), F represents a b-valent organic group derived from a photofunctional compound. , D represents a divalent group, and b represents an integer of 1 to 4. In the formula, a group represented by —SiR ⁹ _3-a (OR ¹⁰ ) _a is a substituted silicon group having a hydrolyzable group (—OR ² ), and R ⁹ is a hydrogen atom, an alkyl group, a substituted or It represents an unsubstituted aryl group, R ¹⁰ represents a hydrogen atom, an alkyl group or a trialkylsilyl group, and a represents an integer of 1 to 3. -SiR ⁹ groups represented by ^{_3-a (OR} _{10) a} has a role of forming three-dimensional Si-O-Si bond by the crosslinking reaction (inorganic glassy network).

  The organic group represented by F in the general formula (I) is an organic group having photoelectric characteristics, more specifically, photocarrier transport characteristics, and is a photofunctional compound conventionally known as a charge transport material. It has the same skeleton as the basic skeleton (the skeleton necessary for exhibiting photoelectric characteristics). Specific examples of the basic skeleton of the organic group represented by F include triarylamine compounds, benzidine compounds, arylalkane compounds, aryl-substituted ethylene compounds, stilbene compounds, anthracene compounds, hydrazone compounds. Basic skeletons of compounds having hole transport properties such as quinone compounds, fluorenone compounds, xanthone compounds, benzophenone compounds, cyanovinyl compounds, ethylene compounds, etc. Is mentioned.

  Preferable examples of the organic group represented by F include groups represented by the following general formula (III). When F is a group represented by the general formula (III), particularly excellent photoelectric characteristics and mechanical characteristics are exhibited.

In general formula (II), Ar ^{1 to} Ar ⁴ may be the same or different and each represents a substituted or unsubstituted aryl group. Ar ⁵ represents a substituted or unsubstituted aryl group or an arylene group. B pieces out of Ar ^{1 to} Ar ⁴ are bonded to a group represented by —D—SiR ⁹ _3-a (OR ¹⁰ ) _a . k represents 0 or 1;
Ar ^{1 to} Ar ⁴ in the general formula (III) are preferably any of the following formulas (III-1) to (III-7).

_{-Ar-Z 's -Ar-Z} m (III-7)
[Wherein, R ¹¹ represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, a phenyl group substituted with an alkyl group having 1 to 4 carbon atoms or an alkoxy group having 1 to 4 carbon atoms, or an unsubstituted phenyl group, represents one selected from the group consisting of an aralkyl group having 7 to 10 carbon ^atoms, R 12 ^{to R 14} each represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms or carbon atoms, 1 represents a phenyl group substituted with 1 to 4 alkoxy groups, or an unsubstituted phenyl group, an aralkyl group having 7 to 10 carbon atoms, and a halogen atom, and Ar represents a substituted or unsubstituted arylene. Represents a group, X represents -D-SiR ⁹ _3-a (OR ¹⁰ ) _a in the general formula (II), m and s each represents 0 or 1, and t represents an integer of 1 to 3, respectively. . ]
Here, as Ar in Formula (III-7), what is represented by following formula (III-7-1) or (III-7-2) is preferable.

[Wherein R ¹⁵ and R ¹⁶ are each a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, an unsubstituted or substituted phenyl group having 1 to 4 carbon atoms, An aralkyl group having 7 to 10 carbon atoms or a halogen atom is represented, and t represents an integer of 1 to 3. ]
Moreover, as Z 'in Formula (III-7), what is represented by either of following formula (III-7-3)-(III-7-10) is preferable.
_{- (CH 2) q - (} III-7-3)
_{- (CH 2 CH 2 O)} r - (III-7-4)

[Wherein, R ¹⁷ and R ¹⁸ are each a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, an unsubstituted or substituted phenyl group having 1 to 4 carbon atoms, 1 type chosen from the group which consists of a C7-10 aralkyl group or a halogen atom, W represents a bivalent group, q and r represent the integer of 1-10, respectively, and t represents 1-3, respectively. Represents an integer. ]
W in the formulas (III-7-9) and (III-7-10) is a divalent group represented by the following (III-7-11) to (III-7-19). Either is preferable.

—CH ₂ — (III-7-11)
_{-C (CH 3) 2 - (} III-7-12)
-O- (III-7-13)
-S- (III-7-14)
_{-C (CF 3) 2 - (} III-7-15)
—Si (CH ₃ ) ₂ — (III-7-16)

[Wherein u represents an integer of 0 to 3]
In general formula (III), Ar ⁵ is an aryl group exemplified in the description of Ar ^{1 to} Ar ⁴ when k is 0, and when k is 1, a predetermined hydrogen atom is taken from the aryl group. Excluded arylene group.

Further, in the general formula (II), the divalent group represented by D is directly bonded to F imparting photoelectric characteristics and a three-dimensional inorganic glassy network -SiR ⁹ _3-a (OR ¹⁰ ) _a In addition, the inorganic glassy network, which has the function of linking the strength and hardness, is imparted with an appropriate flexibility to the inorganic glassy network, and has the function of improving the toughness of the film. Examples of the divalent group represented by D, and _{specifically, -C n H 2n -, -} C n H 2n-2 -, - C n H 2n-4 - 2 divalent hydrocarbon group represented by (n represents an integer of 1~15), - COO -, - S -, - O -, - CH 2 -C 6 H 4 -, - n = CH -, - C 6 H 4 -C 6 H 4 -, A combination of these, or a substituent introduced.

  In general formula (II), b is preferably 2 or more. When b is 2 or more, the photofunctional organosilicon compound represented by the general formula (II) has two or more Si atoms, and it is easy to form an inorganic glassy network and the mechanical strength is improved. Tend to.

  The compound represented by general formula (II) may be used individually by 1 type, and may be used in combination of 2 or more type.

  In addition to the compound represented by the general formula (II), a compound represented by the following general formula (IV) may be used in combination for the purpose of further improving the mechanical strength of the cured film.

B [—SiR ¹⁹ _3-c (OR ²⁰ ) _c ] _d (IV)
In the general formula (IV), —SiR ¹⁹ _3-c (OR ²⁰ ) _c is a substituted silicon group having a hydrolyzable group, and R ¹⁹ , R ²⁰ and c are each R ⁹ in the general formula (II), It represents the same definition as R ¹⁰ and a. B represents a divalent or higher-valent hydrocarbon group that may contain a branch, a group selected from a divalent or higher-valent phenyl group, or —NH—, or a group composed of a combination thereof, and d represents an integer of 2 or more. Represent.

Since the compound represented by the general formula (IV) has a substituted silicon group having a hydrolyzable group represented by -SiR ¹⁹ _3-c (OR ¹⁰ ) _c , the compound represented by the general formula (II) By the reaction with the compound to be formed or the reaction between the compounds represented by the general formula (IV), a Si—O—Si bond is formed to give a three-dimensional crosslinked cured film. When the compound represented by the general formula (IV) and the compound represented by the general formula (II) are used in combination, the crosslinked structure of the cured film tends to be three-dimensional, and the cured film has an appropriate flexibility. Therefore, stronger mechanical strength can be obtained. Preferred examples of the compound represented by the general formula (IV) are shown in Table 1.

  In addition to the compound represented by the general formula (II), another compound capable of crosslinking reaction may be used in combination. As such a compound, various silane coupling agents and commercially available silicone hard coat agents can be used.

  As silane coupling agents, vinyltrichlorosilane, vinyltrimethoxysilane, vinyltriethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltrimethoxy Silane, γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, γ-aminopropylmethyldimethoxysilane, N-β (aminoethyl) γ-aminopropyltriethoxysilane, tetramethoxysilane, methyltrimethoxysilane, Examples include dimethyldimethoxysilane.

  As a commercially available hard coat agent, KP-85, CR-39, X-12-2208, X-40-9740, X-4101007, KNS-5300, X-40-2239 (manufactured by Shin-Etsu Silicone), AY42-440, AY42-441, AY49-208 (manufactured by Toray Dow Corning) and the like.

  A fluorine-containing compound can be added to the protective layer 7 for the purpose of imparting surface lubricity. By improving the surface lubricity, the coefficient of friction with the cleaning member decreases, and the wear resistance can be improved. It also has the effect of preventing the adhesion of discharge products, developer, paper dust, etc. to the surface of the photoreceptor, which helps to improve the life of the photoreceptor.

  As the fluorine-containing compound, a fluorine atom-containing polymer such as polytetrafluoroethylene can be added as it is, or fine particles of these polymers can be added. In the case of a cured film formed of the compound represented by the general formula (II), it is desirable to add a compound capable of reacting with an alkoxysilane as the fluorine-containing compound and configure it as a part of the crosslinked film. Examples of such fluorine-containing compounds include (tridecafluoro-1,1,2,2-tetrahydrooctyl) triethoxysilane, (3,3,3-trifluoropropyl) trimethoxysilane, 3- (heptafluoro Isopropoxy) propyltriethoxysilane, 1H, 1H, 2H, 2H-perfluoroalkyltriethoxysilane, 1H, 1H, 2H, 2H-perfluorodecyltriethoxysilane, 1H, 1H, 2H, 2H-perfluorooctyltri An ethoxysilane etc. are mentioned.

  The content of the fluorine-containing compound is preferably 20% by weight or less based on the total amount of the protective layer 7. When the content of the fluorine-containing compound exceeds 20% by weight, a problem may occur in the film formability of the crosslinked cured film.

  Although the protective layer 7 containing the above compound has sufficient oxidation resistance, an antioxidant may be added for the purpose of imparting stronger oxidation resistance. Antioxidants are preferably hindered phenols or hindered amines, organic sulfur antioxidants, phosphite antioxidants, dithiocarbamate antioxidants, thiourea antioxidants, benzimidazole antioxidants. , Etc., may be used. The content of the antioxidant is preferably 15% by weight or less, more preferably 10% by weight or less, based on the total amount of the protective layer 7.

  Examples of the hindered phenol antioxidant include 2,6-di-t-butyl-4-methylphenol, 2,5-di-t-butylhydroquinone, N, N′-hexamethylene bis (3,5-di). -T-butyl-4-hydroxyhydrocinnamide, 3,5-di-t-butyl-4-hydroxybenzylphosphonate-diethyl ester, 2,4-bis [(octylthio) methyl] -o-cresol, 2 , 6-di-t-butyl-4-ethylphenol, 2,2'-methylenebis (4-methyl-6-t-butylphenol), 2,2'-methylenebis (4-ethyl-6-t-butylphenol), 4,4′-butylidenebis (3-methyl-6-tert-butylphenol), 2,5-di-tert-amylhydroquinone, 2-tert-butyl-6- (3-butyl-2-hydroxy) Proxy-5-methylbenzyl) -4-methylphenyl acrylate, 4,4'-butylidene bis (3-methyl -6-t-butylphenol) and the like.

  In addition, other additives used for forming a known coating film can be added to the protective layer 7, and known materials such as a leveling agent, an ultraviolet absorber, a light stabilizer, and a surfactant are used. be able to.

The protective layer 7 is formed by applying a coating solution containing the above compound onto the charge transport layer 6 and subjecting it to a heat treatment. Thereby, the compound etc. which are represented by general formula (I) raise | generate a crosslinking hardening reaction three-dimensionally, and a firm cured film is formed. The temperature of the heat treatment is not particularly limited as long as it does not affect the lower layer, but is preferably room temperature to 200 ° C, more preferably 100 to 160 ° C.
The crosslinking curing reaction may be performed without a catalyst, or an appropriate catalyst may be used. Catalysts include acid catalysts such as hydrochloric acid, sulfuric acid, phosphoric acid, formic acid, acetic acid, trifluoroacetic acid, bases such as ammonia and triethylamine, organotin compounds such as dibutyltin diacetate, dibutyltin dioctoate, stannous oxalate, Examples thereof include organic titanium compounds such as tetra-n-butyl titanate and tetraisopropyl titanate, iron salts of organic carboxylic acids, manganese salts, cobalt salts, zinc salts, zirconium salts, and aluminum chelate compounds.
Moreover, in order to make easy application | coating of the coating liquid for protective layers, it can add and use a solvent as needed. Specifically, water, methanol, ethanol, n-propanol, i-propanol, n-butanol, benzyl alcohol, methyl cellosolve, ethyl cellosolve, acetone, methyl ethyl ketone, cyclohexanone, methyl acetate, n-butyl acetate, dioxane, tetrahydrofuran, Examples include methylene chloride, chloroform, dimethyl ether, and dibutyl ether. These solvents may be used alone or in a combination of two or more.

Examples of the coating method include a blade coating method, a wire bar coating method, a spray coating method, a dip coating method, a bead coating method, an air knife coating method, and a curtain coating method.
The thickness of the protective layer 7 thus formed is preferably 0.5 to 20 μm, more preferably 2 to 10 μm.

  Next, a preferred embodiment of the image forming apparatus of the present invention will be described.

  FIG. 5 is a cross-sectional view schematically showing a basic configuration of the image forming apparatus according to the first embodiment of the present invention. An image forming apparatus 200 shown in FIG. 5 includes an electrophotographic photosensitive member 207, a charging device 208 that charges the electrophotographic photosensitive member 207, a power source 209 connected to the charging device 208, and an electrophotographic image that is charged by the charging device 208. An exposure device 210 that exposes the photosensitive member 207 to form an electrostatic latent image, a developing device 211 that develops the electrostatic latent image formed by the exposure device 210 with toner, and forms a toner image, and a developing device 211 The image forming apparatus includes a transfer device 212 that transfers the formed toner image to a transfer medium (image output medium) 500, a cleaning device 213, a static eliminator 214, and a fixing device 215. In this case, the static eliminator 214 may not be provided.

  Here, the electrophotographic photosensitive member 207 contains hydroxygallium phthalocyanine having a maximum peak wavelength in the range of 810 to 839 nm in the spectral absorption spectrum in the wavelength range of 600 to 900 nm in the photosensitive layer. Reference numeral 211 denotes a toner that supplies toner having an average shape factor of 100 to 140 to the electrophotographic photosensitive member 207. The configuration of the photosensitive layer is not particularly limited as long as it contains the hydroxygallium phthalocyanine. For example, any of the photosensitive layers shown in FIGS. Details of the developing device 211 will be described later.

  A charging device 208 in FIG. 5 is of a system (contact charging system) in which a conductive member (charging roll) is brought into contact with the surface of the electrophotographic photoreceptor 207 to charge the surface of the photoreceptor 207. In the present invention, a contactless charging device such as corotron or scorotron may be used instead of the contact charging device.

  As the contact-type charging member, a member in which an elastic layer, a resistance layer, a protective layer and the like are provided on the outer peripheral surface of the core material is preferably used. The shape of the conductive member may be any of a brush shape, a blade shape, a pin electrode shape, a roller shape, and the like.

  As the material of the core material, a conductive material such as iron, copper, brass, stainless steel, aluminum, nickel, or the like is used. Also, a resin molded product in which conductive particles or the like are dispersed can be used.

As the material of the elastic layer, a material having conductivity or semiconductivity, for example, a material in which conductive particles or semiconducting particles are dispersed in a rubber material can be used. EPDM, polybutadiene, natural rubber, polyisobutylene, SBR, CR, NBR, silicone rubber, urethane rubber, epichlorohydrin rubber, SBS, thermoplastic elastomer, norbornene rubber, fluorosilicone rubber, ethylene oxide rubber, chloroprene rubber, isoprene Rubber, epoxy rubber or the like is used. Examples of the conductive particles or semiconductive particles include carbon black, zinc, aluminum, copper, iron, nickel, chromium, titanium and other metals, ZnO—Al ₂ O ₃ , SnO ₂ —Sb ₂ O ₃ , In ₂ O ₃ — Metal oxides such as SnO ₂ , ZnO—TiO ₂ , MgO—Al ₂ O ₃ , FeO—TiO ₂ , TiO ₂ , SnO ₂ , Sb ₂ O ₃ , In ₂ O ₃ , ZnO, and MgO can be used. These materials can be used individually by 1 type or in mixture of 2 or more types.

  As the material of the resistance layer and the protective layer, conductive particles or semiconductive particles are dispersed in a binder resin, and the resistance is controlled. As binder resin, acrylic resin, cellulose resin, polyamide resin, methoxymethylated nylon, ethoxymethylated nylon, polyurethane resin, polycarbonate resin, polyester resin, polyethylene resin, polyvinyl resin, polyarylate resin, polythiophene resin, PFA, FEP, A polyolefin resin such as PET, a styrene butadiene resin, or the like is used. As the conductive particles or semiconductive particles, the same carbon black, metal, and metal oxide as the elastic layer are used. If necessary, an antioxidant such as hindered phenol and hindered amine, a filler such as clay and kaolin, and a lubricant such as silicone oil can be added. As a means for forming these layers, blade coating method, Meyer bar coating method, spray coating method, dip coating method, bead coating method, air knife coating method, curtain coating method, melt molding method, injection molding method, etc. should be used. Can do.

When the photosensitive member is charged using these conductive members, a voltage is applied to the conductive member. The applied voltage may be a DC voltage or a DC voltage superimposed with an AC voltage.
The shape of the contact-type charging member may be any shape such as a roller, a blade, or a belt, and can be arbitrarily selected according to the specifications and form of the image forming apparatus.
There is no particular limitation on the charging method used in the electrophotographic photosensitive member of the present invention. However, in recent years, a contact charging method that generates less ozone and has a low environmental load tends to be used preferably. In general, the contact charging method has a weak charging ability as compared with non-contact charging methods such as scorotron and corotron, and is likely to be a problem particularly in an image forming apparatus that requires a high-speed response. When the charging capability is weak, the charge remaining in the photosensitive layer of the electrophotographic photosensitive member causes image quality defects such as fogging. However, according to the electrophotographic photosensitive member of the present invention, since there are few hydroxygallium phthalocyanine pigment particles having a broken crystal type that cause charge to remain in the charge generation layer, the above-described image quality defects occur. It is difficult and can be suitably used in combination with a contact charging system.

  As the exposure apparatus 210, an optical system apparatus that can expose a light source such as a semiconductor laser, an LED (light emitting diode), and a liquid crystal shutter on the surface of the electrophotographic photosensitive member in a desired image-like manner can be used.

As described above, the developing device 211 supplies toner having an average shape factor of 100 to 140 (preferably 100 to 135) to the electrophotographic photosensitive member 207. Due to the excellent shape uniformity of the toner, a high-quality output image can be obtained. Further, since the amount of toner to be discarded can be reduced by improving the transfer efficiency, it is excellent in environmental conservation. Note that if the average shape factor (ML ² / A) is larger than 150, the transfer efficiency is lowered, and the image quality of the output image is lowered to the extent that it can be visually confirmed.

  The average particle size of the toner is preferably 2 to 12 μm, more preferably 3 to 9 μm.

  The toner used in the present invention includes, for example, a binder resin and a colorant. Examples of the binder resin include homopolymers and copolymers such as styrenes, monoolefins, vinyl esters, α-methylene aliphatic monocarboxylic acid esters, vinyl ethers, and vinyl ketones. Typical binder resins include polystyrene, styrene-alkyl acrylate copolymer, styrene-alkyl methacrylate copolymer, styrene-acrylonitrile copolymer, styrene-butadiene copolymer, styrene-maleic anhydride copolymer. Examples thereof include coalescence, polyethylene, and polypropylene. Furthermore, polyester, polyurethane, epoxy resin, silicone resin, polyamide, modified rosin, paraffin wax, and the like can also be mentioned.

  Coloring agents include magnetic powders such as magnetite and ferrite, carbon black, aniline blue, calcoil blue, chrome yellow, ultramarine blue, dupont oil red, quinoline yellow, methylene blue chloride, phthalocyanine blue, malachite green oxalate, and lamp black. Rose Bengal, C.I. I. Pigment red 48: 1, C.I. I. Pigment red 122, C.I. I. Pigment red 57: 1, C.I. I. Pigment yellow 97, C.I. I. Pigment yellow 17, C.I. I. Pigment blue 15: 1, C.I. I. Pigment Blue 15: 3 is a typical example.

  The toner may be internally added or externally added with a known additive such as a charge control agent, a release agent, or other inorganic fine particles.

  Typical examples of the release agent include low molecular weight polyethylene, low molecular weight polypropylene, Fischer-Tropsch wax, montan wax, carnauba wax, rice wax, and candelilla wax.

  Known charge control agents can be used, but charge control agents such as azo-based metal complex compounds, metal complex compounds of salicylic acid, and resin types containing polar groups can be used.

  As other inorganic fine particles, small-sized inorganic fine particles having an average primary particle diameter of 40 nm or less are used for the purpose of powder flowability, charge control, and the like. Inorganic or organic fine particles may be used in combination. As these other inorganic fine particles, known ones can be used.

  In addition, the surface treatment of the small-diameter inorganic fine particles is effective because the dispersibility becomes high and the effect of increasing the powder fluidity increases.

  The method for producing the toner used in the present invention is not particularly limited as long as the average shape factor of the obtained toner satisfies the above conditions, and can be obtained by a known method. Specifically, for example, a kneading and pulverizing method, a method of changing the shape of particles obtained by the kneading and pulverizing method with mechanical impact force or thermal energy, an emulsion polymerization aggregation method, a dissolution suspension method and the like can be mentioned. In addition, a manufacturing method may be performed in which the toner obtained by the above method is used as a core, and agglomerated particles are further adhered and heat-fused to give a core-shell structure. When an external additive is added, it can be produced by mixing the toner and the external additive with a Henschel mixer or a V blender. Further, when the toner is manufactured by a wet method, it can be externally added by a wet method. However, among these, a toner synthesized by a polymerization method is particularly preferably used because of its high shape controllability.

  Examples of the transfer device 212 include a roller-type contact charging member, a contact-type transfer charger using a belt, a film, a rubber blade, or the like, or a scorotron transfer charger or a corotron transfer charger using corona discharge. It is done.

  The transfer device 212 can supply a current having a predetermined current density to the electrophotographic photosensitive member when the toner image formed on the electrophotographic photosensitive member 207 is transferred to the transfer medium 500. Is preferred. As described above, at the time of transfer, by supplying a current to the electrophotographic photosensitive member 207 using a specific hydroxygallium phthalocyanine, prevention of ghost generation and improvement of transfer efficiency can be achieved at a high level. Can do.

  The cleaning device 213 is for removing residual toner adhering to the surface of the electrophotographic photosensitive member after the transfer process. The cleaned electrophotographic photosensitive member is repeatedly used for the image forming process described above. . As the cleaning device, brush cleaning, roll cleaning, and the like can be used in addition to the cleaning blade. Among these, it is preferable to use the cleaning blade. Examples of the material for the cleaning blade include urethane rubber, neoprene rubber, and silicone rubber.

  The image forming apparatus of the present invention may further include an erase light irradiation device 214 as shown in FIG. As a result, when the electrophotographic photosensitive member is repeatedly used, the phenomenon that the residual potential of the electrophotographic photosensitive member is brought into the next cycle is prevented, so that the image quality can be further improved.

  FIG. 6 is a cross-sectional view schematically showing a basic configuration of an image forming apparatus according to the second embodiment of the present invention. The image forming apparatus 230 shown in FIG. 6 transfers the toner image formed on the electrophotographic photosensitive member 207 to the primary transfer member 212a and then supplies it between the primary transfer member 212a and the secondary transfer member 212b. A transfer device of an intermediate transfer system for transferring to a transfer medium (image output medium) 500 to be transferred, and at the time of such transfer, a current having a predetermined current density from the primary transfer member 212a toward the electrophotographic photosensitive member. Can be supplied. Although not shown in FIG. 6, the image forming apparatus 230 may further include a static eliminator as in the image forming apparatus 200 shown in FIG. The other configuration of the image forming apparatus 230 is the same as that of the image forming apparatus 200.

  As described above, in the image forming apparatus 230, the intermediate transfer method is applied. However, as in the case of the image forming apparatus 200 according to the first embodiment, the specific hydroxygallium phthalocyanine is used as the photosensitive layer. By combining the electrophotographic photosensitive member 207 contained in the toner and the developing device 211 that supplies the specific toner to the electrophotographic photosensitive member, a good image quality can be stably obtained over a long period of time.

  Further, when the toner image formed on the electrophotographic photosensitive member 207 is transferred to the primary transfer member 212a, a current having a predetermined current density is supplied from the primary transfer member 212a to the electrophotographic photosensitive member 207. Thus, fluctuations in the transfer current due to the type and material of the transfer medium 500 can be suppressed, so that the amount of charge flowing into the electrophotographic photoreceptor 207 can be accurately controlled. As a result, it is possible to achieve higher image quality and reduced environmental burden at a higher level.

  FIG. 7 is a sectional view schematically showing a basic configuration of an image forming apparatus according to the third embodiment of the present invention. An image forming apparatus 220 shown in FIG. 7 is an intermediate transfer type image forming apparatus. In the housing 400, four electrophotographic photosensitive members 401a to 401d (for example, the electrophotographic photosensitive member 401a is yellow and the electrophotographic photosensitive member 401b is magenta). The electrophotographic photosensitive member 401c can form an image of cyan and the electrophotographic photosensitive member 401d can form a black color) are arranged in parallel along the intermediate transfer belt 409.

  Here, the electrophotographic photoreceptors 401a to 401d mounted on the image forming apparatus 220 contain hydroxygallium phthalocyanine having a maximum peak wavelength in the range of 810 to 839 nm in the spectral absorption spectrum in the wavelength range of 600 to 900 nm, respectively. An electrophotographic photosensitive member having a photosensitive layer.

  Each of the electrophotographic photosensitive members 401a to 401d can be rotated in a predetermined direction (counterclockwise on the paper surface), and the charging rolls 402a to 402d, the developing devices 404a to 404d, and the primary transfer roll 410a along the rotation direction. To 410d and cleaning blades 415a to 415d are arranged. Each of the developing devices 404a to 404d can supply toners of four colors of black, yellow, magenta, and cyan accommodated in toner cartridges 405a to 405d. These toners satisfy the condition that the average shape factor is 100 to 140. Further, the primary transfer rolls 410a to 410d are in contact with the electrophotographic photosensitive members 401a to 401d via the intermediate transfer belt 409, respectively.

  Further, a laser light source (exposure device) 403 is disposed at a predetermined position in the housing 400, and the surface of the electrophotographic photoreceptors 401a to 401d after charging is irradiated with laser light emitted from the laser light source 403. Is possible. Accordingly, charging, exposure, development, primary transfer, and cleaning are sequentially performed in the rotation process of the electrophotographic photosensitive members 401a to 401d, and the toner images of the respective colors are transferred onto the intermediate transfer belt 409 in an overlapping manner. Here, in the tandem color image forming apparatus, the electrophotographic photoreceptors 401a to 401d having the photosensitive layer containing the specific hydroxygallium phthalocyanine are combined with each color toner having an average shape factor of 100 to 140. However, it is possible to achieve high image quality and a reduction in environmental load at a high level.

  The intermediate transfer belt 409 is supported with a predetermined tension by a drive roll 406, a backup roll 408, and a tension roll 407, and can rotate without causing deflection due to the rotation of these rolls. Further, the secondary transfer roll 413 is disposed so as to contact the backup roll 408 via the intermediate transfer belt 409. The intermediate transfer belt 409 passing between the backup roll 408 and the secondary transfer roll 413 is cleaned by, for example, a cleaning blade 416 disposed in the vicinity of the drive roll 406 and then repeatedly used for the next image forming process. Is done.

  A tray (transfer medium tray) 411 is provided at a predetermined position in the housing 400, and the transfer medium 500 such as paper in the tray 411 is transferred to the intermediate transfer belt 409 and the secondary transfer roll by the transfer roll 412. Then, the paper is sequentially transferred between the two fixing rolls 414 that are in contact with each other and the two fixing rolls 414 that are in contact with each other.

  In the above description, the case where the intermediate transfer belt 409 is used as the intermediate transfer member has been described. However, the intermediate transfer member may have a belt shape like the intermediate transfer belt 409 or a drum shape. There may be. Conventionally known resins can be used as the resin material used as the base material of the intermediate transfer member in the belt shape. For example, polyimide resin, polycarbonate resin (PC), polyvinylidene fluoride (PVDF), polyalkylene terephthalate (PAT), ethylenetetrafluoroethylene copolymer (ETFE) / PC, ETFE / PAT, PC / PAT blend material, polyester Resin materials such as polyether ether ketone and polyamide, and resin materials using these as main raw materials. Furthermore, a resin material and an elastic material can be blended and used.

As an elastic material, polyurethane, chlorinated polyisoprene, NBR, chloropyrene rubber, EPDM, hydrogenated polybutadiene, butyl rubber, silicone rubber, or the like can be used, or a material obtained by blending two or more kinds can be used. If necessary, a conductive agent imparting electronic conductivity or a conductive agent having ionic conductivity is added to the resin material and elastic material used for these base materials in combination of one kind or two or more kinds. Among these, it is preferable to use a polyimide resin in which a conductive agent is dispersed from the viewpoint of excellent mechanical strength. As the conductive agent, a conductive polymer such as carbon black, metal oxide, or polyaniline can be used.
When a belt-shaped configuration such as the intermediate transfer belt 409 is employed as the intermediate transfer member, the thickness of the belt is generally preferably 50 to 500 μm and more preferably 60 to 150 μm, but is appropriately selected according to the hardness of the material. be able to.

  For example, a belt made of a polyimide resin in which a conductive agent is dispersed is 5 to 20% by weight as a conductive agent in a polyamic acid solution as a polyimide precursor, as described in JP-A-63-111263. After the carbon black is dispersed, the dispersion is cast on a metal drum and dried, and then the film peeled off from the drum is stretched at a high temperature to form a polyimide film. Can be produced.

  The film molding is generally performed by injecting a polyamic acid solution film-forming stock solution in which a conductive agent is dispersed into a cylindrical mold and, for example, heating at 100 to 200 ° C. at a rotational speed of 500 to 2000 rpm. The film was formed into a film by a centrifugal molding method while rotating, and then the obtained film was demolded in a semi-cured state and covered with an iron core. It can be carried out by proceeding a ring-closing reaction) and carrying out main curing. Also, the stock solution is cast on a metal sheet to a uniform thickness and heated to 100-200 ° C. to remove most of the solvent in the same manner as above, and then gradually raised to a high temperature of 300 ° C. or higher. There is also a method of forming a polyimide film. The intermediate transfer member may have a surface layer.

  When a drum-shaped configuration is adopted as the intermediate transfer member, it is preferable to use a cylindrical substrate formed of aluminum, stainless steel (SUS), copper, or the like as the substrate. If necessary, an elastic layer can be coated on the cylindrical substrate, and a surface layer can be formed on the elastic layer.

  FIG. 8 is a sectional view schematically showing a preferred embodiment of the process cartridge of the present invention. In addition to the electrophotographic photosensitive member 207, the process cartridge 300 is provided with a charging device 208, a developing device 211, a cleaning device (cleaning means) 213, an opening 218 for exposure, and an opening 217 for static elimination exposure. Are combined and integrated with each other. The electrophotographic photosensitive member 207 has a photosensitive layer containing hydroxygallium phthalocyanine having a maximum peak wavelength in the range of 810 to 839 nm in the spectral absorption spectrum in the wavelength range of 600 to 900 nm. The developing device 211 supplies toner having an average shape factor of 100 to 140 to the electrophotographic photosensitive member 207.

  The process cartridge 300 is detachably attached to an image forming apparatus main body including a transfer device 212, a fixing device 215, and other components (not shown), and the image forming apparatus together with the image forming apparatus main body. It constitutes.

  EXAMPLES Hereinafter, although this invention is demonstrated more concretely based on an Example and a comparative example, this invention is not limited by these Examples.

  In addition, the measurement of the spectral absorption spectrum of hydroxygallium phthalocyanine in the following examples and comparative examples was performed as follows. First, at room temperature, a small amount of hydroxygallium phthalocyanine was dispersed ultrasonically in 8 mL of n-butyl acetate to prepare a measurement solution. The spectral absorption spectrum of the obtained measurement liquid was measured using a spectrophotometer (manufactured by Hitachi, Ltd .: U-2000).

  The spectral absorption spectrum of the layer containing hydroxygallium phthalocyanine was measured as follows. First, a coating liquid containing hydroxygallium phthalocyanine was dip-coated on a glass plate to prepare a coating film (sample for spectral absorption spectrum measurement). The solid content ratio of the coating solution was 4.0 to 5.0 wt%, and the pulling rate during dip coating was appropriately adjusted in the range of 50 to 200 mm / min. About the obtained sample, the spectral absorption spectrum was measured using the spectrophotometer (Hitachi Ltd. make: U-2000). The spectral absorption spectrum of the coating film can be measured by various methods even on the electrophotographic photosensitive member. For example, when the layer formed on the surface of the hydroxygallium phthalocyanine pigment-containing layer does not absorb in the range of 600 to 900 nm, it can be obtained by measuring the reflected light spectrum of the electrophotographic photoreceptor. Alternatively, even if the layer formed on the surface of the hydroxygallium phthalocyanine pigment-containing layer exhibits absorption in the range of 600 to 900 nm, these layers are eluted, and the hydroxygallium phthalocyanine pigment-containing layer Can be obtained by measuring the reflected light spectrum.

  The average particle diameter of hydroxygallium phthalocyanine was measured using a laser diffraction / scattering particle size distribution analyzer (Horiba, Ltd .: LA-700).

  The BET specific surface area value was measured by a nitrogen substitution method using a BET specific surface area measuring instrument (manufactured by Shimadzu Corporation: Flow Soap II2300).

Further, the average shape factor of the toner particles was determined as follows. First, for 1000 toner particles, an image of the toner particles was taken from an optical microscope into an image analyzer (LUZEX III: manufactured by Nireco Corporation), and the maximum length and area of the photographed image of the toner particles were determined. Next, the shape factor [(maximum particle length) ² × π × 100 / (area × 4)] is obtained for each toner particle from the obtained maximum length and area, and the average value thereof is calculated as the average shape factor (ML2 / A).

[Example 1]
60 parts by weight of zinc oxide (prototype manufactured by Teika, specific surface area value 16 m ² / g, average particle size 70 nm) subjected to surface treatment with a silane coupling agent (KBM603, manufactured by Shin-Etsu Chemical Co., Ltd.) and a curing agent (blocked) 15 parts by weight of isocyanate, Sumijoule 3175, manufactured by Sumitomo Bayern Urethane Co., Ltd.), 38 parts by weight of a solution obtained by dissolving 15 parts by weight of butyral resin (BM-1, manufactured by Sekisui Chemical Co., Ltd.) in 85 parts by weight of methyl ethyl ketone, and 25 parts by weight of methyl ethyl ketone And mixed. This mixed solution was subjected to a dispersion treatment with a sand mill for 2 hours using 1 mmφ glass beads to obtain a dispersion. As a catalyst, 0.005 part by weight of dioctyltin dilaurate was added to the resulting dispersion to obtain an undercoat layer coating solution. The obtained coating solution was applied on an aluminum substrate having a diameter of 30 mm, a length of 340 mm, and a thickness of 1 mm by a dip coating method, followed by drying and curing at 160 ° C. for 100 minutes to obtain an undercoat layer having a thickness of 20 μm. .

Next, hydroxygallium phthalocyanine having a maximum peak wavelength (λ _max ) in the range of 600 to 900 nm in the spectral absorption spectrum at 827 nm was prepared. Further, when an X-ray diffraction spectrum of this hydroxygallium phthalocyanine using CuKα characteristic X-ray was measured, 7.5 °, 9.9 °, 12.5 °, 16 of Bragg angle (2θ ± 0.2 °) was measured. Diffraction peaks were shown at .3 °, 18.6 °, 25.1 °, and 28.3 °. The average particle diameter of hydroxygallium phthalocyanine was 0.07 nm, and the BET specific surface area value was 68.3 nm. Further, when this hydroxygallium phthalocyanine was observed using a transmission electron microscope, it was confirmed that there were no particles having a primary particle diameter exceeding 0.30 μm (FIG. 11). A mixture of 15 parts by weight of this hydroxygallium phthalocyanine, 10 parts by weight of vinyl chloride-vinyl acetate copolymer resin (VMCH, manufactured by Nihon Unicar Co., Ltd.) as a binder resin, and 300 parts by weight of n-butyl acetate was used as a glass of 1 mmφ. The beads were dispersed in a horizontal sand mill for 100 minutes to obtain a charge generation layer coating solution. The obtained coating solution was dip-coated on the undercoat layer and dried to form a charge generation layer having a thickness of 0.2 μm. When the spectral absorption spectrum of the obtained charge generation layer was measured, the absorption peak ratio (maximum peak in the range of 600 to 700 nm / maximum peak in the range of 810 to 839 nm of the spectral absorption spectrum) was 1.14.

  Furthermore, 4 parts by weight of N, N′-diphenyl-N, N′-bis (3-methylphenyl)-[1,1 ′] biphenyl-4,4′-diamine and the following formula (I- 1-1) A coating solution prepared by dissolving 6 parts by weight of a bisphenol Z polycarbonate resin (viscosity average molecular weight: 40,000) having a structural unit represented by 60 parts by weight of tetrahydrofuran is applied on the charge generation layer, and 130 A charge transport layer having a film thickness of 33 μm was formed by drying at 40 ° C. for 40 minutes to produce an electrophotographic photosensitive member.

  Using the obtained electrophotographic photosensitive member, a color image forming apparatus having the configuration shown in FIG. 7 was produced. The produced image forming apparatus includes a contact charging device and an intermediate transfer member, except that the above-described electrophotographic photosensitive member is used and toner having an average shape factor (ML2 / A) of 126 is used. It was the same as a full-color printer (Fuji Xerox Co., Ltd .: DocuCenter Color 400CP).

  The obtained image forming apparatus was subjected to a print test to evaluate the image quality of the first image and the output image after 600 kcycles (600,000 cycles). The obtained results are shown in Table 2.

[Examples 2 to 4]
In Examples 2 to 4, instead of hydroxygallium phthalocyanine in Example 1, hydroxygallium phthalocyanine having λ _max , average particle diameter, BET specific surface area value, and coating film absorption peak ratio shown in Table 2 was used. An electrophotographic photosensitive member was produced in the same manner as Example 1 except for the above. The spectral absorption spectrum and X-ray diffraction spectrum of hydroxygallium phthalocyanine used in Example 2 are shown in FIGS. 9 and 10, respectively.

  Next, an image forming apparatus was produced in the same manner as in Example 1 except that each of the obtained electrophotographic photosensitive members was used and a toner having an average shape factor shown in Table 2 was used. Went. The obtained results are shown in Table 2. In addition, the presence or absence of particles having a primary particle diameter exceeding 0.3 μm is also shown.

[Comparative Examples 1-6]
In Comparative Examples 1 to 6, instead of hydroxygallium phthalocyanine in Example 1, hydroxygallium phthalocyanine having λ _max , average particle size, BET specific surface area value, and coating film absorption peak ratio shown in Table 2 was used. An electrophotographic photosensitive member was produced in the same manner as Example 1 except for the above.

  Next, an image forming apparatus was produced in the same manner as in Example 1 except that each of the obtained electrophotographic photosensitive members was used and a toner having an average shape factor shown in Table 2 was used. Went. The obtained results are shown in Table 2. In addition, the presence or absence of particles having a primary particle diameter exceeding 0.3 μm is also shown. Furthermore, a transmission electron micrograph of hydroxygallium phthalocyanine used in Comparative Example 2 is shown in FIG.

[Example 5]
Zinc oxide (trial product manufactured by Teika: specific surface area value 16 m ² / g, average particle size 70 nm) subjected to surface treatment with a silane coupling agent (KBM603: manufactured by Shin-Etsu Chemical Co., Ltd.) and a curing agent blocked isocyanate Joule 3175) (manufactured by Sumitomo Bayern Urethane Co., Ltd.): 15 parts by weight and butyral resin BM-1 (manufactured by Sekisui Chemical Co., Ltd.) 38 parts by weight of a solution prepared by dissolving 15 parts by weight of methyl ethyl ketone in 85 parts by weight and methyl ethyl ketone: 25 parts by weight did. This mixed solution was subjected to a dispersion treatment with a sand mill for 1.5 hours using 1 mmφ glass beads to obtain a dispersion. As a catalyst, 0.005 part by weight of dioctyltin dilaurate was added to the resulting dispersion to obtain an undercoat layer coating solution. The obtained coating solution is applied on an aluminum substrate having a diameter of 30 mm, a length of 340 mm, and a wall thickness of 1 mm by dip coating, followed by drying and curing at 160 ° C. for 100 minutes, and an undercoat layer having a thickness of 18 μm. Got.

  Next, 30 parts by weight of an organic zirconium compound (acetylacetone zirconium butyrate) and an organic silane compound (170 parts by weight of n-butyl alcohol in which 4 parts by weight of a polyvinyl butyral resin (S-REC BM-S, manufactured by Sekisui Chemical Co., Ltd.) are dissolved 3 parts by weight of (γ-aminopropyltrimethoxysilane) was mixed and stirred to obtain an intermediate layer coating solution. The obtained coating solution was dip-coated on the undercoat layer and cured at 150 ° C. for 1 hour to obtain an intermediate layer having a thickness of 1.2 μm.

Next, hydroxygallium phthalocyanine having a maximum peak wavelength (λ _max ) in the range of 600 to 900 nm in the spectral absorption spectrum at 827 nm was prepared. Further, when an X-ray diffraction spectrum of this hydroxygallium phthalocyanine using CuKα characteristic X-ray was measured, 7.5 °, 9.9 °, 12.5 °, 16 of Bragg angle (2θ ± 0.2 °) was measured. Diffraction peaks were shown at .3 °, 18.6 °, 25.1 °, and 28.3 °. The average particle diameter of hydroxygallium phthalocyanine was 0.07 nm, and the BET specific surface area value was 68.3 nm. Moreover, when this hydroxygallium phthalocyanine was observed using a transmission electron microscope, it was confirmed that there were no particles having a primary particle diameter exceeding 0.30 μm. A mixture of 15 parts by weight of this hydroxygallium phthalocyanine, 10 parts by weight of vinyl chloride-vinyl acetate copolymer resin (VMCH, manufactured by Nihon Unicar Co., Ltd.) as a binder resin, and 300 parts by weight of n-butyl acetate was used as a glass of 1 mmφ. The beads were dispersed in a horizontal sand mill for 100 minutes to obtain a charge generation layer coating solution. The obtained coating solution was dip-coated on the above intermediate layer and dried to form a charge generation layer having a thickness of 0.2 μm. When the spectral absorption spectrum of the obtained charge generation layer was measured, the absorption peak ratio (maximum peak in the range of 600 to 700 nm / maximum peak in the range of 810 to 839 nm of the spectral absorption spectrum) was 1.14.

  Furthermore, 4 parts by weight of N, N′-diphenyl-N, N′-bis (3-methylphenyl)-[1,1 ′] biphenyl-4,4′-diamine and the above formula (I- 1-1) A coating solution prepared by dissolving 6 parts by weight of a bisphenol Z polycarbonate resin (viscosity average molecular weight: 40,000) having a structural unit represented by 60 parts by weight of tetrahydrofuran is applied on the charge generation layer, and 130 A charge transport layer having a film thickness of 33 μm was formed by drying at 40 ° C. for 40 minutes to produce an electrophotographic photosensitive member.

  Next, an image forming apparatus was produced in the same manner as in Example 1 except that each of the obtained electrophotographic photosensitive members was used and a toner having an average shape factor shown in Table 2 was used. Went. The obtained results are shown in Table 2.

[Examples 6 to 8]
In Examples 6 to 8, instead of hydroxygallium phthalocyanine in Example 5, hydroxygallium phthalocyanine having λ _max , average particle diameter, BET specific surface area value, and coating film absorption peak ratio shown in Table 2 was used. An electrophotographic photosensitive member was produced in the same manner as Example 5 except for the above.

  Next, an image forming apparatus was produced in the same manner as in Example 1 except that each of the obtained electrophotographic photosensitive members was used and a toner having an average shape factor shown in Table 2 was used. Went. The obtained results are shown in Table 2. In addition, the presence or absence of particles having a primary particle diameter exceeding 0.3 μm is also shown.

[Comparative Examples 7 to 9]
In Comparative Examples 7 to 9, in place of hydroxygallium phthalocyanine in Example 5, hydroxygallium phthalocyanine having λ _max , average particle size, BET specific surface area value, and coating film absorption peak ratio shown in Table 2 was used. An electrophotographic photosensitive member was produced in the same manner as Example 5 except for the above.

  Next, an image forming apparatus was produced in the same manner as in Example 1 except that each of the obtained electrophotographic photosensitive members was used and a toner having an average shape factor shown in Table 2 was used. Went. The obtained results are shown in Table 2. In addition, the presence or absence of particles having a primary particle diameter exceeding 0.3 μm is also shown.

[Example 9]
Instead of the bisphenol Z polycarbonate resin represented by the formula (I-1-1) in Example 5, a bisphenol C polyarylate resin represented by the following formula (I-2-1) (viscosity average molecular weight: 40,000) 6 An electrophotographic photosensitive member was produced in the same manner as in Example 5 except that parts by weight were used.

  Next, an image forming apparatus was produced in the same manner as in Example 1 except that each of the obtained electrophotographic photosensitive members was used and a toner having an average shape factor shown in Table 2 was used. Went. The obtained results are shown in Table 2.

[Examples 10 and 11]
In Examples 10 and 11, in place of hydroxygallium phthalocyanine in Example 9, hydroxygallium phthalocyanine having λ _max , average particle diameter, BET specific surface area value, and coating film absorption peak ratio shown in Table 2 was used. An electrophotographic photosensitive member was produced in the same manner as Example 5 except for the above.

  Next, an image forming apparatus was produced in the same manner as in Example 1 except that each of the obtained electrophotographic photosensitive members was used and a toner having an average shape factor shown in Table 2 was used. Went. The obtained results are shown in Table 2. In addition, the presence or absence of particles having a primary particle diameter exceeding 0.3 μm is also shown.

[Comparative Examples 10 and 11]
In Comparative Examples 10 and 11, instead of hydroxygallium phthalocyanine in Example 9, hydroxygallium phthalocyanine having λ _max , average particle diameter, BET specific surface area value, and coating film absorption peak ratio shown in Table 2 was used. An electrophotographic photosensitive member was produced in the same manner as Example 5 except for the above.

  Next, an image forming apparatus was produced in the same manner as in Example 1 except that each of the obtained electrophotographic photosensitive members was used and a toner having an average shape factor shown in Table 2 was used. Went. The obtained results are shown in Table 2. In addition, the presence or absence of particles having a primary particle diameter exceeding 0.3 μm is also shown.

[Comparative Example 12]
Instead of hydroxygallium phthalocyanine in Example 9, the same procedure as in Example 9 was used except that hydroxygallium phthalocyanine having λmax, average particle diameter, BET specific surface area value, and coating film absorption peak ratio shown in Table 2 was used. An electrophotographic photosensitive member was produced.

  Next, an image forming apparatus was produced in the same manner as in Example 1 except that each of the obtained electrophotographic photosensitive members was used and a toner having an average shape factor shown in Table 2 was used. Went. The obtained results are shown in Table 2. In addition, the presence or absence of particles having a primary particle diameter exceeding 0.3 μm is also shown.

1 is a schematic cross-sectional view showing a preferred example of an electrophotographic photosensitive member used in the image forming apparatus of the present invention. FIG. 6 is a schematic cross-sectional view showing another example of an electrophotographic photosensitive member used in the image forming apparatus of the present invention. FIG. 6 is a schematic cross-sectional view showing another example of an electrophotographic photosensitive member used in the image forming apparatus of the present invention. FIG. 6 is a schematic cross-sectional view showing another example of an electrophotographic photosensitive member used in the image forming apparatus of the present invention. 1 is a schematic cross-sectional view showing a preferred embodiment of an image forming apparatus of the present invention. It is a schematic cross-sectional view showing another embodiment of the image forming apparatus of the present invention. It is a schematic cross-sectional view showing another embodiment of the image forming apparatus of the present invention. 1 is a schematic configuration diagram showing a preferred embodiment of a process cartridge of the present invention. 4 is a graph showing a spectral absorption spectrum of hydroxygallium phthalocyanine used in Example 2. FIG. 3 is a graph showing an X-ray diffraction spectrum of hydroxygallium phthalocyanine used in Example 2. FIG. 2 is a transmission electron micrograph of hydroxygallium phthalocyanine used in Example 1. FIG. 2 is a transmission electron micrograph of hydroxygallium phthalocyanine used in Comparative Example 2. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Electrophotographic photoreceptor, 2 ... Conductive substrate, 3 ... Photosensitive layer, 4 ... Undercoat layer, 5 ... Charge generation layer, 6 ... Charge transport layer, 7 ... Protective layer, 8 ... Intermediate layer, 200, 220, 230: Image forming device, 207: Electrophotographic photosensitive member, 208: Charging device, 209 ... Power source, 210 ... Exposure device, 211 ... Developing device, 212 ... Transfer device, 213 ... Cleaning device, 214 ... Static eliminator, 215 ... Fixing Apparatus, 216 ... Mounting rail, 217 ... Opening for static elimination exposure, 218 ... Opening for exposure, 300 ... Process cartridge, 400 ... Housing, 402a to 402d ... Charging roll, 403 ... Laser light source (exposure apparatus) 404a to 404d, developing device, 405a to 405d, toner cartridge, 406, driving roll, 407, tension roll, 408, backup. 409 ... intermediate transfer belt, 410a-410d ... primary transfer roll, 411 ... tray (tray to be transferred), 412 ... transfer roll, 413 ... secondary transfer roll, 414 ... fixing roll, 415a-415d ... cleaning Blades, 416... Cleaning blades, 500.

Claims (7)

A conductive support, and a photosensitive layer containing hydroxygallium phthalocyanine provided on the conductive support and having a maximum peak wavelength in the range of 810 to 839 nm in the spectral absorption spectrum in the wavelength range of 600 to 900 nm. An electrophotographic photoreceptor having
A charging device for charging the electrophotographic photosensitive member;
An exposure apparatus that exposes the charged electrophotographic photosensitive member to form an electrostatic latent image; and
A developing device that supplies toner having an average shape factor of 100 to 140 to the electrophotographic photosensitive member, develops the electrostatic latent image, and forms a toner image on the electrophotographic photosensitive member;
A transfer device for transferring the toner image from the electrophotographic photosensitive member to a transfer medium;
An image forming apparatus comprising: 2. The image forming apparatus according to claim 1, wherein the maximum primary particle diameter of the hydroxygallium phthalocyanine is 0.3 [mu] m or less. The hydroxygallium phthalocyanine has diffraction peaks at Bragg angles (2θ ± 0.2 °) of 7.5 ° and 28.3 ° in an X-ray diffraction spectrum using CuKα characteristic X-ray. The image forming apparatus according to claim 1 or 2. 4. The spectral absorption spectrum of the photosensitive layer, wherein a maximum peak in a range of 600 to 700 nm is larger than a maximum peak in a range of 810 to 839 nm. Image forming apparatus. The image forming apparatus according to claim 1, wherein the electrophotographic photoreceptor further includes an undercoat layer between the conductive support and the photosensitive layer. . The image forming apparatus according to claim 5, wherein the undercoat layer contains inorganic fine particles. A conductive support, and a photosensitive layer containing hydroxygallium phthalocyanine provided on the conductive support and having a maximum peak wavelength in the range of 810 to 839 nm in the spectral absorption spectrum in the wavelength range of 600 to 900 nm. An electrophotographic photoreceptor having
A developing device capable of supplying toner having an average shape factor of 100 to 140 to the electrophotographic photoreceptor;
A process cartridge comprising:

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