JP2006259387A - Electrophotographic photoreceptor, electrophotographic image forming apparatus and process cartridge equipped with the electrophotographic photoreceptor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electrophotographic photoreceptor suppressing generation of a ghost image in a wide range with respect to the transfer voltage in a transferring step and capable of obtaining a favorable output image, and to provide an electrophotographic image forming apparatus and a process cartridge equipped with the electrophotographic photoreceptor. <P>SOLUTION: The electrophotographic photoreceptor has a photosensitive layer on a substrate where at least the surface thereof is conductive, wherein the photosensitive layer contains a hydroxygallium phthalocyanine pigment showing a maximum peak at 810 to 839 nm in a 600 to 900 nm range of a spectral absorption spectrum and a resorcinarene compound. The electrophotographic image forming apparatus and the process cartridge are equipped with the electrophotographic photoreceptor. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an electrophotographic photosensitive member, an electrophotographic image forming apparatus including the electrophotographic photosensitive member, and a process cartridge.

  An electrophotographic image forming apparatus is widely used as a copying machine, a laser beam printer, and the like because it has an advantage of high speed and high printing quality. As electrophotographic photoreceptors used in these electrophotographic image forming apparatuses, organic photoreceptors using organic photoconductive materials are widely used because they are inexpensive and have excellent advantages in manufacturability and discardability. Yes. Among these, the functionally separated organic photoconductor in which a charge generation layer that generates a charge upon exposure and a charge transport layer that transports a charge is laminated in terms of electrophotographic characteristics such as sensitivity, chargeability and repeated stability. It is excellent, various proposals have been made, and it has been put to practical use. Furthermore, for the charge generation layer, phthalocyanine pigments that are inexpensive and have excellent advantages in terms of manufacturability and safety are preferably used. In particular, an electrophotographic photoreceptor using a hydroxygallium phthalocyanine pigment as a charge generation material has higher sensitivity than conventional electrophotographic photoreceptors due to its high charge generation capability.

  Conventionally, the charge generation layer is generally formed by applying and drying a dispersion in which a charge generation material is dispersed in a solution in which a binder resin is dissolved in an organic solvent. It has been found that the state of the charge generating substance in the dispersion has a great influence on the electrical characteristics and image characteristics when the electrophotographic photosensitive member is obtained. The main factors that the charge generation material in the dispersion affects the properties of the electrophotographic photosensitive member are the dispersion state of the charge generation material in the dispersion and the crystalline state (molecular arrangement) of the charge generation material itself. And so on. With regard to dispersibility, a method for evaluating dispersibility in the spectral absorption spectrum of a dispersion by using a ratio of absorbance at a wavelength without absorption inherent to the charge generation material and absorbance at an arbitrary peak wavelength has been proposed. On the other hand, a preferable dispersibility value is disclosed (for example, see Patent Document 1). In particular, when the charge generation material is a phthalocyanine pigment, the crystal state affects the electrical characteristics, so it is important to control and maintain the crystal state in a desired state.

  In general, it is known that phthalocyanine pigments are divided into several crystal types depending on the production method or processing method, and that the photoelectric conversion characteristics of phthalocyanine pigments are greatly affected if the crystal types are different. With regard to the crystal form of the phthalocyanine pigment, for example, in the case of a metal-free phthalocyanine pigment, crystal forms such as α-type, β-type, π-type, and X-type are known. Furthermore, regarding the gallium phthalocyanine crystal, many reports have been made on its crystal type and electrophotographic characteristics. The Bragg angle (2θ ± 0.2 °) with respect to the CuKα characteristic X-ray is 7.5 °, 9.9 °. Hydroxygallium phthalocyanine having diffraction peaks at 12.5 °, 16.3 °, 18.6 °, 25.1 °, and 28.3 ° and an electrophotographic photosensitive member using the same exhibit extremely high sensitivity. (For example, refer nonpatent literature 1.).

The electrophotographic photoreceptor using the hydroxygallium phthalocyanine pigment has such a high charge generation capability, but the photogenerated charge tends to remain in the photosensitive layer, and the exposure history in the previous cycle appears in the next cycle. The problem is that this phenomenon is likely to occur. The mechanism by which this ghost occurs is not clear, but can be estimated as follows. For example, in the case of an image forming method using a reversal development after negatively charging a laminated electrophotographic photosensitive member whose photosensitive layer is composed of a charge generation layer and a charge transport layer, some of the holes generated by image exposure are charged. By accumulating in the generation layer and moving to the surface of the charge transport layer immediately after the charging process of the next cycle, the surface potential is lowered. As a result, a phenomenon called so-called positive ghost, in which the image of the previous cycle appears deeply, occurs. On the other hand, if some of the holes generated by image exposure accumulate near the interface between the charge generation layer and the charge transport layer and remain unopened in the next cycle, the effective electric field in the charge generation layer As the intensity decreases and the number of charges generated by image exposure decreases, a so-called negative ghost phenomenon occurs in which the image of the previous cycle appears lightly.
With respect to positive ghosts and negative ghosts as described above, there has been proposed a technique for reducing the degree of generation thereof by containing a resorcinarene compound in the photosensitive layer (see, for example, Patent Document 2), but a sufficient improvement effect. Cannot be obtained.
JP-A-10-97088 JP 2002-229228 A Journal of Imaging Science and Technology, Vol. 40, no. 3, May / June, 249 (1996)

  In addition, the electrophotographic image forming apparatus includes a transfer process in which the toner image formed on the electrophotographic photosensitive member is transferred to an image output medium such as paper or a transfer medium such as an intermediate transfer member. In this transfer step, when toner is transferred from the electrophotographic photosensitive member to the transfer medium, it is necessary to apply a potential having a polarity opposite to the charged polarity of the toner particles to the transfer medium. Furthermore, in the case of an electrophotographic image forming apparatus using reversal development, a potential having a polarity opposite to the charged polarity on the surface of the electrophotographic photosensitive member is applied to the surface of the electrophotographic photosensitive member by the transfer medium, and accordingly the electrophotographic photosensitive member is applied. Charge flows into the body. At this time, on the surface of the electrophotographic photosensitive member, more electric charge flows into a region where the toner image is not formed as compared with a region where the toner image is formed. In this way, the charge flowing from the surface of the electrophotographic photosensitive member in the transfer step remains after moving to the inside of the photosensitive layer, and changes the effective electric field strength inside the photosensitive layer in the next cycle, so that the image of the previous cycle is changed. Appears as a ghost. For example, in the case of an image forming method using reversal development after negatively charging a laminated electrophotographic photosensitive member whose photosensitive layer is composed of a charge generation layer and a charge transporting layer, in the transfer process, holes are transferred from the surface of the electrophotographic photosensitive member. Is injected and accumulated in the vicinity of the interface between the charge generation layer and the charge transport layer, and in the next cycle, the effective electric field strength in the charge generation layer is increased, thereby increasing the number of thermally excited charges generated. By reducing the surface potential of the photosensitive member, a so-called negative ghost phenomenon occurs in which the image of the previous cycle appears lightly. With regard to ghosts generated by external charge inflow stress in the transfer process, no technique has been found that can provide a sufficient improvement effect. In particular, the occurrence of such a ghost is greatly affected by the transfer voltage. Therefore, a ghost improvement technique that can cope with various transfer voltages is desired.

In view of the above, the present invention has been made in view of the problems of the above-described conventional techniques, and an object thereof is to achieve the following object.
That is, the present invention provides an electrophotographic photosensitive member, an electrophotographic image forming apparatus including the electrophotographic photosensitive member, and a process cartridge capable of suppressing generation of ghosts and obtaining a good output image. With the goal.
The present invention also provides an electrophotographic photosensitive member capable of widely suppressing ghosting with respect to a transfer voltage in a transfer step and obtaining a good output image, and an electrophotographic image forming apparatus including the electrophotographic photosensitive member. Another object is to provide an apparatus and a process cartridge.

  As a result of intensive research to achieve the above object, the present inventors have found that a ghost phenomenon that occurs in an electrophotographic photoreceptor using a conventional hydroxygallium phthalocyanine pigment is contained in the photosensitive layer of the electrophotographic photoreceptor. It has been found that the crystal structure of the hydroxygallium phthalocyanine pigment is caused by a decrease in dispersibility due to the nonuniformity of the coarse particles and particle shape of the pigment. As a result of further investigation based on such knowledge, a hydroxygallium phthalocyanine pigment having a predetermined atomization state and particle uniformity and having a spectral absorption spectrum having an absorption maximum at a specific wavelength is used as a charge generation material. The present inventors have found that the above-mentioned problems can be solved by using a resorcinarene compound in combination with the photosensitive layer, and the present invention has been completed.

The electrophotographic photosensitive member of the present invention is an electrophotographic photosensitive member having a photosensitive layer on a substrate having a conductive surface at least.
The photosensitive layer contains a hydroxygallium phthalocyanine pigment having absorption at a maximum peak of 810 to 839 nm in the range of 600 to 900 nm of the spectral absorption spectrum, and a resorcinarene compound represented by the following general formula (1). Features.

(In the formula, R ¹ represents a hydrogen atom, an alkyl group which may have a substituent, or an aryl group which may have a substituent, and R ² represents an aromatic which may have a substituent. An aromatic hydrocarbon group or a heterocyclic group which may have a substituent, wherein R ² is a group in which a plurality of aromatic hydrocarbon groups are bonded or a group in which a plurality of heterocyclic groups are bonded. May be.)

  Further, the electrophotographic image forming apparatus of the present invention includes an electrophotographic photosensitive member of the present invention, a charging device for charging the electrophotographic photosensitive member, and an electrostatic latent image formed by exposing the charged electrophotographic photosensitive member. And a developing device that develops the electrostatic latent image to form a toner image, and a transfer device that transfers the developed toner image to a transfer medium.

  Further, the process cartridge of the present invention includes the electrophotographic photosensitive member of the present invention, a charging device for charging the electrophotographic photosensitive member, and an exposure device for exposing the charged electrophotographic photosensitive member to form an electrostatic latent image. A developing device that develops the electrostatic latent image to form a toner image, and at least one device selected from a cleaning device that cleans the electrophotographic photosensitive member, and is attached to and detached from the electrophotographic image forming apparatus main body. It is characterized by being free.

At least one of the following aspects (1) to (7) can be applied to the electrophotographic photosensitive member, the electrophotographic image forming apparatus, and the process cartridge of the present invention.
(1) A mode in which the number of particles having a particle diameter of 0.3 μm or more in the hydroxygallium phthalocyanine pigment is 1 or less per 30 μm ² on a transmission electron microscope observation image.
(2) The aspect in which the hydroxygallium phthalocyanine pigment does not contain particles having a particle size of 0.3 μm or more.
(3) An embodiment in which the hydroxygallium phthalocyanine pigment has diffraction peaks at 7.5 ° and 28.3 ° of Bragg angles (2θ ± 0.2 °) with respect to CuKα characteristic X-rays.

(4) A mode in which the photosensitive layer has a maximum peak size in the range of 600 to 700 nm of the spectral absorption spectrum larger than the maximum peak in the range of 810 to 839 nm.
(5) An aspect having an undercoat layer between the substrate and the photosensitive layer.
(6) The aspect in which the undercoat layer (5) contains metal oxide fine particles.
(7) The photosensitive layer has at least a charge generation layer and a charge transport layer, and the charge generation layer contains the hydroxygallium phthalocyanine pigment and the resorcinarene compound.

Usually, in the phthalocyanine pigment, the interaction between phthalocyanine molecules varies depending on the molecular arrangement in the crystal, and as a result, the state of the molecular arrangement appears in the spectral absorption spectrum. Conventionally, V-type hydroxygallium phthalocyanine pigments have an absorption maximum at 840 to 870 nm, suggesting the presence of strong intermolecular interactions. This means that there are many sites (sites) where charges can remain in the crystal. Sites present in the crystal easily trap (charge) the charges generated by image exposure. Therefore, when a hydroxygallium phthalocyanine pigment having many such sites is contained in the photosensitive layer of the electrophotographic photoreceptor, it is presumed that ghosts in the next cycle are likely to occur.
In contrast, the hydroxygallium phthalocyanine pigment used in the electrophotographic photosensitive member of the present invention has an absorption maximum in the range of 600 to 900 nm in the spectral absorption spectrum at 810 to 839 nm, which is compared with the conventional hydroxygallium phthalocyanine pigment. This suggests that the intermolecular interaction is small. For this reason, the number of sites present in the crystal is also reduced, so that charges generated by image exposure in the previous cycle are less likely to remain, and as a result, it is assumed that the generation of ghost in the next cycle is suppressed.
In addition, the present invention is characterized in that the above-mentioned hydroxygallium phthalocyanine pigment is used as a charge generation material in the photosensitive layer, and a resorcinarene compound represented by the general formula (1) is added thereto. To do. By adopting such a configuration, the number of sites present in the crystal of the hydroxygallium phthalocyanine pigment as described above is reduced, and the charge generated from the resorcinarene compound is selectively captured at the sites. The photosensitive layer can be formed in a state where charges are trapped in the site in advance before image exposure.

Therefore, since the electrophotographic photoreceptor of the present invention contains both the hydroxygallium phthalocyanine pigment and the resorcinarene compound as described above in the photosensitive layer, a part of the charge generated by image exposure remains in the photosensitive layer. This makes it possible to suppress not only ghosts generated but also ghosts generated by external charge inflow stress in the transfer process, and it is possible to stably obtain a high-quality output image.
Further, the electrophotographic photoreceptor of the present invention is less susceptible to external charge inflow stress in the transfer process due to the structure of the photosensitive layer, so that it is possible to suppress ghosts widely with respect to the transfer voltage. .

As described above, according to the present invention, the electrophotographic photosensitive member, the electrophotographic image forming apparatus including the electrophotographic photosensitive member, and the process cartridge capable of suppressing generation of a ghost and obtaining a good output image are provided. Can be provided.
Further, according to the present invention, an electrophotographic photosensitive member capable of suppressing generation of a ghost widely with respect to a transfer voltage in a transfer step and obtaining a good output image, and an electrophotographic type equipped with the electrophotographic photosensitive member. An image forming apparatus and a process cartridge can be provided.

  The electrophotographic photosensitive member, electrophotographic image forming apparatus, and process cartridge of the present invention will be described in detail below.

<Electrophotographic photoreceptor>
The electrophotographic photosensitive member of the present invention is an electrophotographic photosensitive member having a photosensitive layer on a substrate having a conductive surface at least.
The photosensitive layer has a hydroxygallium phthalocyanine pigment (hereinafter, referred to as “specific hydroxygallium phthalocyanine pigment” as appropriate) having an absorption at a maximum peak of 810 to 839 nm in a spectral absorption spectrum of 600 to 900 nm, and the above general formula. And a resorcinarene compound represented by (1) (hereinafter, appropriately referred to as “specific resorcinarene compound”).
Thus, the electrophotographic photoreceptor of the present invention is characterized by having a photosensitive layer containing a specific hydroxygallium phthalocyanine pigment and a specific resorcinarene compound. Since this photosensitive layer can form a state in which charges are trapped in advance before the image exposure, a part of the charges generated by the image exposure remains inside the photosensitive layer. Not only ghosts but also ghosts generated by external charge inflow stress in the transfer process can be suppressed. As a result, a high-quality output image can be stably obtained. Further, because of the structure of such a photosensitive layer, it is difficult to be greatly affected by external charge inflow stress in the transfer process, so that it is possible to suppress ghosts widely with respect to the transfer voltage.
First, the specific hydroxygallium phthalocyanine pigment and the specific resorcinarene compound, which are constituent components of the recording layer in the electrophotographic photoreceptor of the present invention, will be described.

[Specific hydroxygallium phthalocyanine pigment]
The specific hydroxygallium phthalocyanine pigment in the present invention requires that the maximum peak in the range of 600 to 900 nm of the spectral absorption spectrum has absorption at 810 to 839 nm, and the maximum peak preferably has absorption at 810 to 830 nm.
It is suggested that such a specific hydroxygallium phthalocyanine pigment has a smaller intermolecular interaction than a conventional hydroxygallium phthalocyanine pigment. For this reason, the number of sites present in the crystal is also reduced, so that charges generated by image exposure in the previous cycle are less likely to remain, and as a result, it is assumed that the generation of ghost in the next cycle is suppressed. Here, FIG. 9 illustrates a spectral absorption spectrum of the specific hydroxygallium phthalocyanine pigment in the present invention.
In addition, what has absorption in the range whose maximum peak in the range of 600-900 nm of a spectral absorption spectrum is smaller than 810 nm is difficult to manufacture, and what has absorption in the range whose maximum peak is larger than 839 nm is intermolecular. The interaction cannot be made sufficiently small.

Further, the specific hydroxygallium phthalocyanine pigment has one particle having a particle diameter of 0.3 μm or more in the hydroxygallium phthalocyanine pigment per 30 μm ² on the transmission electron microscope image from the viewpoint of further improving the effect of suppressing the generation of ghosts. Preferably, the number of particles having a particle diameter of 0.2 μm or more is 1 or less per 30 μm ² on a transmission electron microscope observation image. In particular, the specific hydroxygallium phthalocyanine pigment preferably does not contain particles having a particle size of 0.3 μm or more.

Further, the surface area of the specific hydroxygallium phthalocyanine pigment at the BET specific surface area is preferably in the range of 45~90m ² / g, more preferably in the range of 50~80m ² / g, 55~80m ² / G is more preferable.
When the particle size and the surface area are within such ranges, the number of contact points between the specific hydroxygallium phthalocyanine pigment and the specific resorcinarene compound increases. A state in which the generated charges are trapped can be more effectively formed.

  In addition, the specific hydroxygallium phthalocyanine pigment preferably has diffraction peaks at 7.5 ° and 28.3 ° of Bragg angles (2θ ± 0.2 °) with respect to CuKα characteristic X-rays. FIG. 10 illustrates a diffraction peak with respect to the Bragg angle (2θ ± 0.2 °) in the CuKα characteristic X-ray of the specific hydroxygallium phthalocyanine pigment in the present invention.

  The above-mentioned spectral absorption spectrum and Bragg angle with respect to the CuKα characteristic X-ray in the specific hydroxygallium phthalocyanine pigment are values determined by various factors such as crystal structure (state), size, particle size distribution, dispersion state, and the like. Although an example is described below about the preparation method of the specific hydroxygallium phthalocyanine pigment used as the value of the said range about each factor, it is not limited to the said method.

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 converted into fine particles and converted into I-type hydroxygallium phthalocyanine. Here, the acid pasting treatment specifically refers to a solution obtained by dissolving crude gallium phthalocyanine in an acid such as sulfuric acid or an acid salt such as a sulfate into an aqueous alkaline solution, water or ice water. Means to recrystallize. 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.

Thereafter, the I-type hydroxygallium phthalocyanine obtained by the acid pasting process is wet-pulverized with a solvent to be refined while undergoing crystal conversion.
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, and preferably a spherical medium having an outer diameter of 0.2 to 2.5 mm. It 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. Furthermore, when the media is not spherical, but has other shapes such as a columnar shape or an indefinite shape, the grinding efficiency is reduced, the media is easily worn by grinding, and the abrasion powder becomes an impurity, and the characteristics of the hydroxygallium phthalocyanine pigment are improved. There is a tendency to be easily deteriorated.
The material of the media is not particularly limited, but is preferably one that hardly causes image quality defects even when mixed in a specific 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 is preferably one that hardly causes image quality defects even when mixed in the specific hydroxygallium phthalocyanine pigment, glass, zirconia, alumina, meno, polypropylene, Teflon (registered trademark), 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, Teflon (registered trademark), polyphenylene sulfide, or the like.
The amount of the media used varies depending on the apparatus used, but is 50 parts by mass or more, preferably 55 to 100 parts by mass with respect to 1 part by mass 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 mass (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.

  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 usage-amount of these solvents is 1-200 mass parts normally with respect to 1 mass part of hydroxygallium phthalocyanine pigments, Preferably it is 1-100 mass parts.

  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.

  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 hydroxygallium phthalocyanine pigment in the wet pulverization process is greatly affected by the scale of the wet pulverization, the stirring speed, the media material, and the like. It is preferable to determine the wet pulverization time.

  Absorption wavelength measurement of wet pulverization treatment liquid for crystal conversion state so that specific hydroxygallium phthalocyanine pigment after wet pulverization treatment has a maximum peak wavelength in the range of 810-839 nm in the spectral absorption spectrum in the wavelength range of 600-900 nm It is preferable that the wet pulverization treatment time is determined while monitoring and is continued until the crystal is converted into a specific 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 obtained 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 specific hydroxygallium phthalocyanine pigment particles are uniformly finely divided, and further, multiple wet pulverization processes are performed in multiple lots. In such a case, it is possible to suppress variation in quality between lots.

The specific hydroxygallium phthalocyanine pigment in the present invention is preferably used as a dispersion by dispersing it. Therefore, the specific hydroxygallium phthalocyanine pigment can be subjected to surface treatment in order to improve dispersibility as long as the position of the absorption peak is maintained within a predetermined range.
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, polyhydroxy titanium 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.

  The content of the specific hydroxygallium phthalocyanine pigment in the present invention is such that, in terms of the expression of the charge generation function and the dispersion stability of the specific hydroxygallium phthalocyanine pigment particles in the photosensitive layer, The range is preferably 1 to 80% by mass, more preferably 20 to 80% by mass, and still more preferably 30 to 75% by mass.

[Specific resorcinarene compounds]
The specific resorcinarene compound in the present invention has a structure represented by the following general formula (1).

In the general formula (1), R ¹ represents a hydrogen atom, an alkyl group that may have a substituent, or an aryl group that may have a substituent. The four R ¹ in the molecule may be the same or different.
As said alkyl group, C1-C5 alkyl groups, such as a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, are mentioned.
In addition, examples of the aryl group include groups such as phenyl and naphthyl.
Examples of substituents that can be introduced into these alkyl groups and aryl groups include halogen atoms such as fluorine, chlorine, bromine and iodine; hydroxy groups; nitro groups; cyano groups; alkyl groups such as methyl, ethyl, propyl and butyl; Aryl groups such as methoxy and ethoxy; alkylamino groups such as dimethylamino and diethylamino; arylamino groups such as phenylamino and diphenylamino; halomethyl groups such as trifluoromethyl; It is done.

In the general formula (1), R ² represents an aromatic hydrocarbon group which may have a substituent or a heterocyclic group which may have a substituent. R ² may be a combination of a plurality of aromatic hydrocarbon groups or a combination of a plurality of heterocyclic groups. Further, the four R ² in the molecule may be the same or different from each other.
Examples of the aromatic hydrocarbon ring constituting the aromatic hydrocarbon ring group include benzene, naphthalene, fluorene, phenanthrene, anthracene, fluoranthene, or pyrene.
Examples of the heterocyclic ring constituting the heterocyclic group include furan, thiophene, pyridine, indole, benzothiazole, carbazole, benzocarbazole, acridone, dibenzothiophene, benzoxazole, benzotriazole, oxathiazole, thiazole, phenazine, cinnoline and benzocine. Norin and the like can be mentioned.
Examples of those in which a plurality of aromatic hydrocarbon groups are bonded or those in which a plurality of heterocyclic groups are bonded include triphenylamine, diphenylamine, N-methyldiphenylamine, biphenyl, terphenyl, binaphthyl, fluorenone, phenance. Examples include lenquinone, anthraquinone, benzanthrone, diphenyloxazole, phenylbenzoxazole, diphenylmethane, diphenylsulfone, diphenylether, benzophenone, stilbene, distyrylbenzene, tetraphenyl-p-phenylenediamine, and tetraphenylbenzidine.
In addition, as a substituent that can be introduced into an aromatic hydrocarbon group or a heterocyclic group, those listed as substituents that can be introduced into the alkyl group or aryl group can be used.

  Hereinafter, although the specific example of the specific resorcinarene compound in this invention is shown, this invention is not limited to this.

Such a specific resorcinarene compound can be synthesized by a known method. For example, first, J.A. Am. Chem. Soc. , Vol. 111, no. 14, 1989, p5397-5404, and a resorcinalene compound in which R ² is hydrogen is synthesized by dehydrating condensation of a resorcinol derivative and various aldehyde compounds using acids such as sulfuric acid and hydrochloric acid. Thereafter, a specific resorcinarene compound is synthesized by an azo coupling coupling reaction between the obtained R ² hydrogen resorcinarene compound and a diazo compound derivative. Such a method for introducing an azo group into R ² is described in, for example, CHEMISTRY LETTERS, pp. 1219-1222, 1990.

  The content of the specific resorcinarene compound is such that the specific hydroxygallium phthalocyanine, which is a charge generating material, is used from the viewpoint of manifesting a ghost improving effect, solubility in a photosensitive layer forming solution, and production of a uniform photosensitive layer. It is preferable that it is 0.05-20 mass% with respect to a pigment, It is more preferable that it is 0.1-10 mass%, Furthermore, it is more preferable that it is 0.2-5 mass%.

Next, preferred embodiments of the electrophotographic photosensitive member of the present invention will be described in detail with reference to the drawings.
1 to 4 are schematic cross-sectional views each showing a preferred embodiment of the electrophotographic photosensitive member of the present invention. The electrophotographic photosensitive members 1a to 1d are arranged with respect to the stacking direction of the conductive substrate 2 and the photosensitive layer 3. FIG. Cut by a vertical plane.
The electrophotographic photoreceptors 1a to 1d 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. It has been.

The configuration of the electrophotographic photoreceptors 1a to 1d will be described in more detail.
The electrophotographic photoreceptor 1a shown in FIG. 1 has a configuration in which a photosensitive layer 3 is formed by laminating a charge generation layer 5 and a charge transport layer 6 in this order on a conductive substrate 2.
The electrophotographic photoreceptor 1b shown in FIG. 2 has an undercoat layer 4 on a conductive substrate 2, and a charge generating layer 5 and a charge transport layer 6 are laminated on the undercoat layer 4 in this order. It is the structure which has.
The electrophotographic photoreceptor 1c shown in FIG. 3 has a subbing layer 4 on a conductive substrate 2, and a photosensitive layer 3 in which a charge generation layer 5 and a charge transport layer 6 are laminated in this order. And further has a surface protective layer 7 thereon.
The electrophotographic photoreceptor 1d shown in FIG. 4 has an undercoat layer 4 and an intermediate layer 8 in this order on a conductive substrate 2, and a charge generation layer 5 and a charge transport layer 6 are laminated in this order on the conductive base 2. The photosensitive layer 3 is formed.

Although the electrophotographic photoreceptor of the present invention is not shown, when the photosensitive layer is not a function separation type photoreceptor, that is, the photosensitive layer may be a single layer. Even in the case where the photosensitive layer is a single layer, an undercoat layer, an intermediate layer, and a surface protective layer can be appropriately provided in the same manner as in the above-described function separation type photoreceptor.
For example, in the electrophotographic photosensitive member of the present invention, a photosensitive layer composed of an undercoat layer and a single layer is laminated in this order on a conductive substrate, and an undercoat layer and a single layer are formed on the conductive substrate. Even if the photosensitive layer and the surface protective layer are laminated in this order, the undercoat layer, the intermediate layer, and the photosensitive layer consisting of a single layer are laminated in this order on the conductive substrate. Good.
Hereinafter, each component of the electrophotographic photosensitive member of the present invention will be described in detail.

[Conductive substrate]
The conductive substrate is made of a metal such as aluminum, copper, iron, zinc, or nickel; on a substrate such as sheet, paper, plastic, or glass; aluminum, copper, gold, silver, platinum, palladium, titanium, nickel-chromium, Deposited metal such as stainless steel and copper-indium; Deposited conductive metal compound such as indium oxide and tin oxide on the base; Laminated metal foil on the base; Carbon black, indium oxide, oxidized Examples include tin-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 may be any of a drum shape, a sheet shape, and a plate shape.

  When a metal pipe base is used as the conductive base, the surface of the pipe base may be a raw pipe, but the base surface may be roughened by surface treatment in advance. . 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.

[Underlayer]
Materials used for the undercoat layer include: zirconium chelate compounds, zirconium alkoxide compounds, organic zirconium compounds such as zirconium coupling agents; titanium chelate compounds, titanium alkoxide compounds, organic titanium compounds such as titanate coupling agents; aluminum chelate compounds, Organic aluminum 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 tin chelates Organotin compounds such as compounds; Aluminum silicon alkoxide compounds; Aluminum titanium Al Kishido compounds; aluminum zirconium alkoxide compounds; and organic metal 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.

  For the undercoat layer, vinyltrichlorosilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris-2-methoxyethoxysilane, vinyltriacetoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-methacryloxypropyl Trimethoxysilane, γ-aminopropyltriethoxysilane, γ-chloropropyltrimethoxysilane, γ-2-aminoethylaminopropyltrimethoxysilane, γ-mercapropropyltrimethoxysilane, γ-ureidopropyltriethoxysilane, β It can be used by containing a silane coupling agent such as -3,4-epoxycyclohexyltrimethoxysilane.

  Furthermore, the undercoat layer includes polyvinyl alcohol, polyvinyl methyl ether, poly-N-vinyl imidazole, polyethylene oxide, ethyl cellulose, methyl cellulose, ethylene-acrylic acid copolymer, polyamide, polyimide, casein, gelatin, polyethylene, polyester, Known binder resins such as phenol resin, vinyl chloride-vinyl acetate copolymer, 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.

  In the present invention, the undercoat layer preferably contains metal oxide fine particles. 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 at least one selected from tin oxide, titanium oxide, and zinc oxide. Metal 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, an electron transporting pigment may 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 properties such as cyano groups, nitro groups, nitroso groups, and halogen atoms. And organic pigments such as bisazo pigments and phthalocyanine pigments having the above substituents, 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 decreases and a coating film defect is generated. Therefore, it is used in a range of 95% by mass or less, preferably 90% by mass or less, based on the total solid content of the undercoat layer. The

The undercoat layer is formed by applying a coating solution (undercoat layer coating solution) in which the above materials are mixed / dispersed in a predetermined organic solvent on a conductive substrate and removing the organic 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 an organometallic compound or a binder 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 undercoat layer coating solution is dried at a temperature at which the organic solvent is evaporated and a film can be formed.
The thickness of the undercoat layer 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 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.

[Middle layer]
As the material used for the intermediate layer, similarly to the material used for the undercoat layer, an organic zirconium compound such as a zirconium chelate compound, a zirconium alkoxide compound or a zirconium coupling agent; a titanium chelate compound, a titanium alkoxide compound or a titanate coupling Organic titanium compounds such as agents; Organoaluminum compounds such as aluminum chelate compounds and 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 chelate compounds Organic manganese compounds; organotin compounds such as tin alkoxide compounds and tin chelate compounds; aluminum silicon Sid 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.

  In addition, as in the case of the undercoat layer, the intermediate layer includes vinyltrichlorosilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris-2-methoxyethoxysilane, vinyltriacetoxysilane, γ-glycidoxypropyltrimethoxy. Silane, γ-methacryloxypropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-chloropropyltrimethoxysilane, γ-2-aminoethylaminopropyltrimethoxysilane, γ-mercapropropyltrimethoxysilane, γ- Silane coupling agents such as ureidopropyltriethoxysilane and 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.

  In the intermediate layer, as in the case of the undercoat layer, 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 properties such as cyano groups, nitro groups, nitroso groups, and halogen atoms. And organic pigments such as bisazo pigments and phthalocyanine pigments having the above substituents, 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 decreases and a coating film defect is generated. Therefore, it is used in a range of 95% by mass or less, preferably 90% by mass or less, based on the total solid content of the intermediate layer. .

As in the case of the undercoat layer, the intermediate layer is obtained by applying a coating solution (intermediate layer coating solution) in which the above materials are mixed / dispersed in a predetermined organic solvent on a conductive substrate, and removing the solvent by drying. It is formed by.
Examples of the mixing / dispersing method in preparing the intermediate layer coating solution include a ball mill, a roll mill, a sand mill, an attritor, and an ultrasonic wave.
Any organic solvent may be used as long as it does not cause gelation or aggregation when an organic metal compound or a binder 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 intermediate layer coating solution is dried at a temperature at which the organic solvent is evaporated and a film can be formed.
The thickness of the intermediate layer thus obtained is preferably from 0.1 to 10 μm, and more preferably from 0.5 to 5 μm.
When the film thickness of the intermediate layer satisfies the above conditions, stable characteristics can be obtained even when the electrophotographic photosensitive member is used continuously for a long time.

[Photosensitive layer]
The electrophotographic photoreceptor of the present invention requires that the photosensitive layer contains a specific hydroxygallium phthalocyanine pigment and a specific resorcinarene compound. As in a preferred embodiment of the present invention, when the electrophotographic photoreceptor of the present invention is a function-separated photoreceptor having a photosensitive layer in which a charge generation layer and a charge transport layer are separately provided, a specific hydroxy The gallium phthalocyanine pigment and the specific resorcinarene compound are contained in the charge generation layer.

The photosensitive layer containing the specific hydroxygallium phthalocyanine pigment and the specific resorcinarene compound preferably has a maximum peak size in the range of 600 to 700 nm of the spectral absorption spectrum larger than the maximum peak in the range of 810 to 839 nm. . The specific hydroxygallium phthalocyanine pigment in the present invention usually becomes a coating solution for a photosensitive layer in which pigment particles are uniformly dispersed through a dispersion treatment step to which a commonly used method is applied. In this dispersion treatment step, the particle size distribution of the hydroxygallium phthalocyanine pigment of the present invention is made uniform. As a result, in the photosensitive layer containing the hydroxygallium phthalocyanine pigment of the present invention, it is presumed that the maximum absorption peak in the range of 600 to 700 nm is larger than the maximum absorption peak in the range of 810 to 839 nm.
As the dispersion processing method, any known method can be used as long as the relationship between the maximum absorption peak in the range of 600 to 700 nm and the maximum absorption peak in the range of 810 to 839 nm can be maintained in the photosensitive layer. .

In the spectral absorption spectrum of the photosensitive layer, the ratio of the absorbance of the maximum absorption peak in the range of 600 to 700 nm to the absorbance of the maximum absorption peak at 810 to 839 nm ((absorbance of the maximum absorption peak in the range of 600 to 700 nm) / (810 The absorbance of the maximum absorption peak in the 839 nm range)) is preferably from 1.01 to 1.40, more preferably from 1.10 to 1.35.
When the electrophotographic photosensitive member of the present invention is a function-separated type photosensitive member, the specific hydroxygallium phthalocyanine pigment and the specific resorcinarene compound are contained in the charge generation layer, so that the spectral absorption spectrum of the charge generation layer is as described above. It is preferable to have a maximum absorption peak of the following relationship.

(Charge generation layer)
When the electrophotographic photoreceptor of the present invention is a function-separated photoreceptor having a photosensitive layer in which a charge generation layer and a charge transport layer are provided separately, the charge generation layer comprises a binder resin (binder resin), It contains a specific hydroxygallium phthalocyanine pigment as a generating substance and a specific resorcinarene compound. In addition, in the range which does not impair the effect of this invention, you may use together charge generating substances other than a specific hydroxygallium phthalocyanine pigment.
The charge generation layer has a configuration in which a specific hydroxygallium phthalocyanine pigment and a specific resorcinarene compound are 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-vinylcarbazole, 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 compounding ratio (mass ratio) of the charge generating substance (specific hydroxygallium phthalocyanine pigment) 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. preferable.

When forming the charge generation layer, a coating solution is used in which the specific hydroxygallium phthalocyanine pigment and the specific resorcinarene compound are dispersed in a solution in which a binder resin is dissolved in a predetermined organic solvent.
As the organic solvent of the coating solution for the charge generation layer, those capable of dissolving the binder resin, for example, alcohols, aromatics, halogenated hydrocarbons, ketones, ketone alcohols, ethers, esters, etc. Solvents 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 the method for dispersing the specific hydroxygallium phthalocyanine pigment and the specific resorcinarene compound in the binder resin liquid include a ball mill, a roll mill, a sand mill, an attritor, and an ultrasonic wave.

As long as the position and maximum particle diameter of the absorption maximum of the hydroxygallium phthalocyanine pigment and the spectral absorption spectrum as the layer are maintained within a predetermined range, the charge generation layer is used to improve the electrical characteristics and image quality. Various additives can also be added.
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, titanium Umukireto 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.

(Charge transport layer)
The charge transport layer 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 diamino compounds such as amino compounds, N, N′-diphenyl N, N′-bis (3-methylphenyl)-[1,1′-biphenyl] -4,4′-diamine 1,2,4-triazine derivatives such as 3- (4′-dimethylaminophenyl) -5,6-di- (4′-methoxyphenyl) -1,2,4-triazine, 4-diethylaminobenzaldehyde-1 , 1-diphenylhydrazone, 4-diphenylaminobenzaldehyde-1,1-diphenylhydrazone, hydrazone derivatives such as [p- (diethylamino) phenyl]-(1-naphthyl) -phenylhydrazone, 2-phenyl-4-styrylquinazoline, etc. Quinazoline derivatives, benzofuran derivatives such as 6-hydroxy-2,3-di (p-methoxyphenyl) benzofuran, α-stilbene derivatives such as p- (2,2-diphenylvinyl) -N, N′-diphenylaniline, Enamine derivatives, carbazole derivatives such as N-ethylcarbazole, poly-N -Hole transport materials such as vinyl carbazole and its derivatives. 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 is preferably a resin capable of forming an electrically 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, silicone-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, salt Vinylidene polymer waxes, polyurethanes, and the like. Among these, the polycarbonate resin represented by the following structural formula (A) and the polyarylate resin represented by the following structural formula (B) are preferably used in terms of compatibility with the charge transport material, solubility in a solvent, and strength. It is done.

In the structural formula (A), R ^{1 to} R ⁸ each independently represents a hydrogen atom, an alkyl group, an alkyl group, an aralkyl group, a substituted or unsubstituted aryl group, or a halogen atom, and X is A substituted or unsubstituted alkylene group, a substituted or unsubstituted cycloalkylene group, or a substituted or unsubstituted arylene group is represented. n represents an integer.

In the structural formula (B), R ^{1 to} R ⁸ each independently represents a hydrogen atom, an alkyl group, an alkyl group, an aralkyl group, a substituted or unsubstituted aryl group, or a halogen atom, and X is Represents a substituted or unsubstituted alkylene group, a substituted or unsubstituted cycloalkylene group, or a substituted or unsubstituted arylene group, and Y represents a substituted or unsubstituted benzene ring, biphenyl ring, naphthalene ring, aliphatic hydrocarbon group Or represents a cyclic hydrocarbon group. 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 (mass 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 is formed by applying a charge transport layer coating liquid containing the above material onto the charge generation layer 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 is preferably 5 to 50 μm, more preferably 10 to 40 μm.

Additives such as antioxidants and light stabilizers are added to the charge transport layer for the purpose of preventing deterioration of the electrophotographic photosensitive member due to ozone, oxidizing gas, or light / heat generated in the image forming apparatus. be able to.
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 the organic sulfur antioxidant 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, and 2,2′-dihydroxy-4-methoxybenzophenone.
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.

  Other compounds include 2,4-di-t-butylphenyl-3 ', 5'-di-t-butyl-4'-hydroxybenzoate, nickel dibutyl-dithiocarbamate, and the like.

Further, at least one kind of electron accepting substance can be included for the purpose of improving sensitivity, reducing residual potential, reducing fatigue during repeated use, and the like.
Examples of the electron acceptor 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 electron-withdrawing substituents are particularly preferred.

Moreover, a solid lubricant and a metal oxide can be dispersed in the charge transport layer for the purpose of reducing wear. Solid lubricants include fluorine-containing resin particles (ethylene tetrafluoride, ethylene trifluoride chloride, ethylene tetrafluoride hexafluoropropylene resin, vinyl fluoride resin, vinylidene fluoride resin, ethylene difluoride dichloride, and those And the like, and silicon-containing resin particles. Examples of the metal oxide include silica, alumina, titanium oxide, tin oxide and the like. When the solid lubricant is dispersed, the friction coefficient on the surface of the charge transport layer decreases, 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 solid lubricant and metal oxide, methods such as a roll mill, a ball mill, a vibrating 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.

[Surface protective layer]
A surface protective layer can be formed on the electrophotographic photosensitive member of the present invention as necessary. As a surface protective layer, the cured film formed including the compound represented by the following general formula (I) is preferable.

F- [DA] _b General formula (I)

In the general formula (I), F represents an organic group derived from a photofunctional compound, D represents a divalent group, and A represents a water represented by —SiR ¹ _3-a (OR ² ) _a. The substituted silicon group which has a decomposable group is represented, b represents the integer of 1-4. Here, R ¹ represents a hydrogen atom, an alkyl group, or a substituted or unsubstituted aryl group, and R ² represents a hydrogen atom, an alkyl group, or a trialkylsilyl group. a represents an integer of 1 to 3.

A substituted silicon group having a hydrolyzable group represented by A in the general formula (I), that is, —SiR ¹ _3-a (OR ² ) _a , has a three-dimensional Si—O—Si bond ( It plays a role in forming an inorganic glassy network.

  In general formula (I), F is an organic group having photoelectric characteristics, more specifically, photocarrier transport characteristics, and the structure of a photofunctional compound conventionally known as a charge transport material is used as it is. be able to. Specific examples of the organic group represented by F include triarylamine compounds, benzidine compounds, arylalkane compounds, aryl-substituted ethylene compounds, stilbene compounds, anthracene compounds, hydrazone compounds, and the like. Examples include a compound skeleton having a hole transport property, and a compound skeleton having an electron transport property such as a quinone compound, a fluorenone compound, a xanthone compound, a benzophenone compound, a cyanovinyl compound, and an ethylene compound.

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

In the general formula (II), Ar ^{1 to} Ar ⁴ each independently 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 ¹ _3-a (OR ² ) _a . k represents 0 or 1;
Ar ^{1 to} Ar ⁴ in the general formula (II) are preferably any of the following formulas (II-1) to (I-7).

_{-Ar-Z 's -Ar-X} m (II-7)

In the above formula, R ⁶ 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, an unsubstituted phenyl group, Or an aralkyl group having 7 to 10 carbon atoms, and R ^{7 to} R ⁹ are each independently a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, or an alkyl group having 1 to 4 carbon atoms. A phenyl group substituted by an alkoxy group, an unsubstituted phenyl group, an aralkyl group having 7 to 10 carbon atoms, or a halogen atom is represented, Ar represents a substituted or unsubstituted arylene group, and X represents a general formula (I ) -D-SiR ¹ _3-a (OR ² ) _a , m and s each represent 0 or 1, and t represents an integer of 1 to 3, respectively.
Here, as Ar in Formula (II-7), what is represented by following formula (II-8) or (II-9) is preferable.

In the above formula, R ¹⁰ and R ¹¹ are each a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms or a phenyl group substituted with an alkoxy group having 1 to 4 carbon atoms, unsubstituted A phenyl group, a C7-10 aralkyl group, or a halogen atom is represented, and t represents an integer of 1-3.

  Moreover, as Z 'in said formula (II-7), what is represented by either of following formula (II-10)-(II-17) is preferable.

_{- (CH 2) q - (} II-10)

_{- (CH 2 CH 2 O)} r - (II-11)

In the above formula, R ¹² and R ¹³ are each independently a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms or a phenyl group substituted with an alkoxy group having 1 to 4 carbon atoms. , An unsubstituted phenyl group, an aralkyl group having 7 to 10 carbon atoms, or a halogen atom, W represents a divalent group, q and r each independently represent an integer of 1 to 10, and t represents 1 Represents an integer of ~ 3.

W in the formulas (II-16) and (II-17) is preferably any one of divalent groups represented by the following (II-18) to (II-26).
—CH ₂ — (II-18)
—C (CH ₃ ) ₂ — (II-19)
-O- (II-20)
-S- (II-21)
_{-C (CF 3) 2 - (} II-22)
—Si (CH ₃ ) ₂ — (II-23)

  In said formula, u represents the integer of 0-3.

In the general formula (II), 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, the aryl group is selected from the aryl group. An arylene group excluding a hydrogen atom.

In the general formula (I), the divalent group represented by D plays a role of linking F that imparts photoelectric characteristics and A that is directly bonded to a three-dimensional inorganic glassy network, On the other hand, it imparts moderate flexibility to an inorganic glassy network that is brittle and plays a role 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 (I), b is preferably 2 or more. When b is 2 or more, the photofunctional organosilicon compound represented by the general formula (I) has two or more Si atoms, which facilitates formation of an inorganic glassy network and improves mechanical strength. Tend to.
The compound represented by general formula (I) may be used individually by 1 type, and may be used together 2 or more types.

  A compound represented by the following general formula (III) may be used in combination with the compound represented by the general formula (I) for the purpose of further improving the mechanical strength of the cured film.

    B-An general formula (III)

In general formula (III), A represents a substituted silicon group having a hydrolyzable group represented by —SiR ¹ _3-a (OR ² ) _a . Here is the same as R ^1, R ^2, a is R ¹ in the general formula ^{(I), R 2, a} . B is composed of at least one group selected from a divalent or higher valent hydrocarbon group, a divalent or higher valent phenyl group, and —NH—, which may contain a branch, or a combination thereof. n represents an integer of 2 or more.

The compound represented by the general formula (III) is a compound having a substituted silicon group having a hydrolyzable group represented by A, that is, —SiR ¹ _3-a (OR ² ) _a . The compound represented by the general formula (III) has a Si—O—Si bond formed by a reaction with a compound represented by the general formula (I) or a reaction between the compounds represented by the general formula (III). Form a three-dimensional cross-linked cured film. When the compound represented by the general formula (III) and the compound represented by the general formula (I) 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 (III) are shown in Table 1.

In addition to the compound represented by the general formula (I), 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.
Commercially available hard coat agents include KP-85, CR-39, X-12-2208, X-40-9740, X-41-1007, KNS-5300, X-40-2239 (above, Shin-Etsu Chemical Co., Ltd.) Product), AY42-440, AY42-441, AY49-208 (manufactured by Toray Dow Corning).

In addition, a fluorine-containing compound can be added to the surface protective layer 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, and the like 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. Moreover, in the case where the surface protective layer is a cured film formed of the compound represented by the general formula (I), a fluorine-containing compound that can react with alkoxysilane is added to constitute a part of the crosslinked film. Is desirable. 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 mass or less based on the total amount of the surface protective layer. When the content of the fluorine-containing compound exceeds 20% by mass, a problem may occur in the film formability of the crosslinked cured film.

The surface protective layer containing the above compound has sufficient oxidation resistance, but 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 mass or less, more preferably 10% by mass or less, based on the total amount of the surface protective layer.
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) Ci-5-methylbenzyl) -4-methylphenyl acrylate, 4,4′-butylidenebis (3-methyl-6-tert-butylphenol) and the like.

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

The surface protective layer is formed by applying a coating solution containing the above compound onto the charge transport layer or the photosensitive layer and subjecting it to a heat treatment. Thereby, the compound etc. which are represented with 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 surface protection layers, a solvent can be added and used 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 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 film thickness of the surface protective layer thus formed is preferably 0.5 to 20 μm, more preferably 2 to 10 μm.

<Electrophotographic image forming apparatus>
The electrophotographic image forming apparatus of the present invention (hereinafter sometimes simply referred to as “image forming apparatus”) includes the electrophotographic photosensitive member of the present invention, a charging device for charging the electrophotographic photosensitive member, An exposure device for exposing the electrophotographic photosensitive member to form an electrostatic latent image, a developing device for developing the electrostatic latent image to form a toner image, and transferring the developed toner image to a transfer medium And a transfer device.
The image forming apparatus of the present invention will be described below with reference to the drawings.
Here, FIGS. 5 and 6 are cross-sectional views schematically showing a basic configuration of a preferred embodiment of the image forming apparatus of the present invention.

  An image forming apparatus 200a shown in FIG. 5 is charged by the electrophotographic photosensitive member 207 of the present invention, a charging device 208 for charging the electrophotographic photosensitive member 207, a power source 209 connected to the charging device 208, and the charging device 208. An exposure device 210 that exposes the electrophotographic 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; The image forming apparatus includes a transfer device 212 that transfers a toner image formed by the device 211 to the transfer medium 500, a cleaning device 213, a static eliminator 214, and a fixing device 215. The present invention may be an image forming apparatus in which the static eliminator 214 is not provided.

An image forming apparatus 200b shown in FIG. 6 is charged by the electrophotographic photosensitive member 207 of the present invention, a charging device 208 for charging the electrophotographic photosensitive member 207, a power source 209 connected to the charging device 208, and the charging device 208. An exposure device 210 that exposes the electrophotographic 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; The toner image formed on the electrophotographic photosensitive member 207 by the apparatus 211 is transferred to the primary transfer member 212a, and then transferred to the transfer medium 500 supplied between the primary transfer member 212a and the secondary transfer member 212b. An intermediate transfer type transfer device, a cleaning device 213, and a fixing device 215. Here, at the time of primary transfer, a current having a predetermined current density can be supplied from the primary transfer member 212a toward the electrophotographic photosensitive member 207.
Although not shown in FIG. 6, the image forming apparatus 200b may further include a static eliminator in the same manner as the image forming apparatus 200a shown in FIG.
Hereinafter, components of the image forming apparatuses 200a and 200b of the present invention will be described.

The electrophotographic photoreceptor 207 is the above-described electrophotographic photoreceptor of the present invention, and any structure can be used as long as the photosensitive layer contains a specific hydroxygallium phthalocyanine pigment and a specific resorcinarene compound. That is, the electrophotographic photosensitive member 207 may have a single photosensitive layer, or may be a function-separated type photosensitive member as shown in FIGS.
The electrophotographic photosensitive member 207 of the present invention is particularly preferably used in an intermediate transfer system in which a toner image formed on an electrophotographic photosensitive member is once transferred to an intermediate transfer member and then transferred to an image output medium. Further, it is more preferably used in a system in which an image is formed by adjusting and controlling the transfer voltage applied from the intermediate transfer member onto the electrophotographic photosensitive member to be constant.

  In the image forming apparatus of the present invention, there is no particular limitation on the charging method applied to the charging device. 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 capability as compared with non-contact charging methods such as scorotron and corotron, and is particularly problematic 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 are present. It is hard to occur and can be suitably used in combination with a contact charging system.

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, and can be arbitrarily selected according to the specifications and form of the image forming apparatus.
As the material of the core material, a conductive material such as iron, copper, brass, stainless steel, aluminum, nickel, or the like is used. Further, a resin molded product in which conductive particles or the like are dispersed can be used.
As the material of the elastic layer, a conductive or semiconductive material, for example, a rubber material in which conductive particles or semiconductive particles are dispersed 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 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.

The resistance layer and the protective layer are preferably those in which conductive particles or semiconductive particles are dispersed in a binder resin and the resistance is controlled. Binder resins include 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 Polyolefin resin such as PET, styrene butadiene resin or the like is used. As the conductive particles or semiconductive particles, carbon black, metal, or metal oxide similar to the elastic layer is used. Moreover, antioxidants, such as hindered phenol and hindered amine, fillers, such as clay and kaolin, and lubricants, such as silicone oil, can be added as needed.
As a means for forming these layers, a blade coating method, a Meyer bar coating method, a spray coating method, a dip coating method, a bead coating method, an air knife coating method, a curtain coating method, a melt molding method, an injection molding method, or the like is used. be able to.

  When the electrophotographic 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.

  As the exposure device 210, an optical system device 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 207 in a desired image-like manner can be used.

As the developing device 211, a conventionally known developing device using a regular or reversal developer such as a one-component system or a two-component system can be used.
The shape of the toner used in the developing device 211 is not particularly limited, and it can be used even if it is indefinite, spherical, or other specific shape. However, a spherical toner is preferably used from the viewpoint of high image quality and ecology. The spherical toner is a toner having a spherical shape represented by an average shape factor (ML ² / A) of 100 to 145, preferably 100 to 140, in order to achieve high transfer efficiency. If this average shape factor (ML ² / A) is larger than 145, the transfer efficiency is lowered, and the deterioration of the image quality of the print sample can be visually confirmed. Such spherical toners can preferably use particles having a volume average particle diameter of 2 to 12 μm, more preferably 3 to 9 μm.
The toner applied to the present invention including such a spherical toner includes at least 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 be given.

  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-diameter inorganic fine particles having an average primary particle size of 40 nm or less are used for the purpose of powder flowability, charge control, etc., and if necessary, larger diameters are used to reduce adhesion. These inorganic or organic fine particles may be used in combination. Known inorganic fine particles 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 toner is not particularly limited by the production method, and can be obtained by a known method. In particular, as a toner production method, specifically, for example, a kneading pulverization method, a method of changing the shape of particles obtained by the kneading pulverization method with a mechanical impact force or thermal energy, an emulsion polymerization aggregation method, Examples thereof include a dissolution suspension method. In addition, a manufacturing method may be performed in which the spherical toner obtained by the above method is used as a core, and agglomerated particles are further adhered and heated and fused to give a core-shell structure. When the external additive is added, it can be produced by mixing the spherical toner and the external additive with a Henschel mixer or a V blender. In addition, when the spherical toner is manufactured by a wet method, it can be externally added by a wet method.

  As the transfer device 212, the primary transfer member 212a, and the secondary transfer member 212b, a roller-type contact charging member, a contact-type transfer charger using a belt, a film, a rubber blade, or the like, or corona discharge is used. Examples include a scorotron transfer charger and a corotron transfer charger.

  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.

  Further, the image forming apparatus of the present invention may include a static eliminator 214 as shown in FIG. An erase light irradiation device is used as the static eliminator 214. As a result, when the electrophotographic photosensitive member 207 is repeatedly used, the phenomenon that the residual potential of the electrophotographic photosensitive member is brought into the next cycle is prevented, so that image quality can be further improved.

  The transfer medium 500 in the present invention is not particularly limited as long as it is a medium that transfers a toner image formed on the surface of the electrophotographic photosensitive member 207.

FIG. 7 is a cross-sectional view schematically showing a basic configuration of another embodiment of the image forming apparatus of the present invention. An image forming apparatus 200c shown in FIG. 7 is an intermediate transfer type image forming apparatus. In the housing 400, four electrophotographic photoreceptors 401a to 401d (for example, the electrophotographic photoreceptor 401a is yellow and the electrophotographic photoreceptor 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 200c are the electrophotographic photoreceptors of the present invention.

  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 be supplied with toner of four colors of black, yellow, magenta and cyan accommodated in the toner cartridges 405a to 405d, and the primary transfer rolls 410a to 410d are respectively intermediate transfer belts. 409 is in contact with the electrophotographic photoreceptors 401a to 401d.

  Further, a laser light source (exposure device) 403 is disposed at a predetermined position in the housing 400, and the surface of the charged electrophotographic photoreceptors 401a to 401d 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.

  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 that has passed 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 in the next image forming process. Provided.

  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, and then discharged to the outside of the housing 400.

  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. Also good. In the case of a belt shape, a conventionally known resin can be used as the resin material used as the base of the intermediate transfer member. 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 electron conductivity or a conductive agent having ionic conductivity is added to the resin material and elastic material used for these substrates, or a combination of two or more types. 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 mass as a conductive agent in a polyamic acid solution, which is a polyimide precursor, as described in JP-A-63-311263. The carbon black was dispersed, the dispersion was cast on a metal drum and dried, and then the film peeled off from the drum was 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 being rotated, and then the obtained film was demolded in a semi-cured state and covered with an iron core, and subjected to a polyimide reaction (polyamide acid) at a high temperature of 300 ° C. or higher. 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. Further, 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.
The transfer medium described in this patent is not particularly limited as long as it is a medium that transfers a toner image formed on an electrophotographic photosensitive member. For example, when transferring directly from an electrophotographic photosensitive member to a transfer medium such as paper, it indicates a transfer medium, and when an intermediate transfer body is used, it indicates an intermediate transfer body.

<Process cartridge>
The process cartridge of the present invention includes the electrophotographic photosensitive member of the present invention, 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, A developing device that develops an electrostatic latent image to form a toner image and at least one device selected from a cleaning device that cleans the electrophotographic photosensitive member, and is detachable from the main body of the electrophotographic image forming apparatus. It is characterized by being.
The process cartridge of the present invention will be described below with reference to the drawings.
Here, FIG. 8 is a cross-sectional view schematically showing a basic configuration of a preferred embodiment of a process cartridge including the electrophotographic photosensitive member of the present invention.

As shown in FIG. 8, the process cartridge 300 includes an electrophotographic photoreceptor 207, a charging device 208, a developing device 211, a cleaning device (cleaning means) 213, an opening 218 for exposure, and an opening for static elimination exposure. The part 217 is combined and integrated using the mounting rail 216.
The process cartridge 300 is detachable from an image forming apparatus main body including a transfer device 212, a fixing device 215, and other components not shown. It constitutes.

In the process cartridge shown in FIG. 8, the electrophotographic photosensitive member 207, the charging device 208, the developing device 211, the cleaning device (cleaning means) 213 of the present invention, the opening 218 for exposure, and the opening 217 for static elimination exposure. However, these devices can be selectively combined as appropriate.
For example, in the process cartridge of the present invention, in addition to the electrophotographic photosensitive member 207, a charging device 208, a developing device 211, a cleaning device (cleaning means) 213, an opening 218 for exposure, and an opening for static elimination exposure. What is necessary is just to provide at least 1 sort (s) selected from the group which consists of 217.

  Since the image forming apparatus and the process cartridge described above are provided with the electrophotographic photosensitive member of the present invention, the occurrence of ghost is suppressed, and a high level of image quality can be stably obtained even in long-term use.

EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples.

<Measurement of physical properties>
[Measurement of spectral absorption spectrum of hydroxygallium phthalocyanine pigment]
The spectral absorption spectra of the hydroxygallium phthalocyanine pigments used in the following examples and comparative examples were measured as follows.
A small amount of the hydroxygallium phthalocyanine pigment was dispersed in 8 mL of n-butyl acetate at room temperature with an ultrasonic wave 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).

[Measurement of Spectral Absorption Spectrum of Layer Containing Hydroxygallium Phthalocyanine Pigment (Charge Generation Layer)]
The spectral absorption spectrum of the layer containing the hydroxygallium phthalocyanine pigment used in the following examples and comparative examples was measured as follows.
A layer coating solution containing a hydroxygallium phthalocyanine pigment (charge generation layer coating solution prepared in the following examples and comparative examples) is dip coated on a glass plate to prepare a sample for measuring the spectral absorption spectrum of the coating film did. The solid content ratio of the coating solution was 4.0 to 5.0% by mass, and the lifting speed 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).
Here, the values shown in Table 2 and Table 3 below are the ratio of the absorbance at the maximum peak in the range of 600 to 700 nm to the absorbance at the maximum peak in the range of 810 to 839 nm ((the absorbance of the maximum absorption peak in the range of 600 to 700 nm). ) / (Absorbance of the maximum absorption peak in the range of 810 to 839 nm)).

  The spectral absorption spectrum of the layer containing the hydroxygallium phthalocyanine pigment can be measured by various methods even on the electrophotographic photoreceptor. For example, when the layer formed on the surface of the layer containing the hydroxygallium phthalocyanine pigment does not absorb in the range of 600 to 900 nm, the reflected light spectrum of the electrophotographic photoreceptor may be measured. Alternatively, even if the layer formed on the surface of the layer containing the hydroxygallium phthalocyanine pigment absorbs in the range of 600 to 900 nm, these layers are eluted and contain the hydroxygallium phthalocyanine pigment. What is necessary is just to measure the reflected light spectrum from a layer.

[Measurement of X-ray diffraction spectrum of hydroxygallium phthalocyanine pigment]
The measurement of the X-ray diffraction spectrum of the hydroxygallium phthalocyanine pigment in the following Examples and Comparative Examples was performed under the following conditions using CuKα characteristic X-rays by a powder method.
Measuring instrument: X-ray diffractometer Miniflex manufactured by Rigaku Corporation
X-ray tube: Cu
Tube current: 15 mA
Scan speed: 5.0 deg. / Min
Sampling interval: 0.02 deg.
Start angle (2θ): 5 deg.
Stop angle (2θ): 35 deg.
Step angle (2θ): 0.02 deg.

[Confirmation of presence of particles having a particle size of 0.3 μm or more]
The hydroxygallium phthalocyanine pigments in the following examples and comparative examples were observed with a transmission electron microscope, and the number of particles having a particle size of 0.3 μm or more per 30 μm ² region was examined.

[Example 1]
60 parts by mass 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.), curing agent (blocked) 15 parts by mass of isocyanate, Sumijour 3175, manufactured by Sumitomo Bayern Urethane Co., Ltd.) and 38 parts by mass of a solution obtained by dissolving 15 parts by mass of butyral resin (BM-1, manufactured by Sekisui Chemical Co., Ltd.) in 85 parts by mass of methyl ethyl ketone, and 25 parts by mass of methyl ethyl ketone And a dispersion was obtained by dispersing for 2 hours in a sand mill using 1 mmφ glass beads. To the obtained dispersion, 0.005 parts by mass of dioctyltin dilaurate was added as a catalyst to prepare a coating solution for an undercoat layer.
The obtained coating solution for the undercoat layer 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 and a thickness of 20 μm. A pulling layer was obtained.

Next, a specific hydroxygallium phthalocyanine pigment-1 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 as follows.

(Preparation of specific hydroxygallium phthalocyanine pigment-1)
30 parts by mass of 1,3-diiminoisoindoline and 9.1 parts by mass of gallium trichloride were added to 230 parts by mass of dimethyl sulfoxide and reacted at 160 ° C. with stirring for 6 hours to obtain reddish purple crystals. The obtained crystal was washed with dimethyl sulfoxide, then washed with ion-exchanged water, and dried to obtain 28 parts by mass of crude crystals of type I chlorogallium phthalocyanine.
Next, 10 parts by mass of the obtained crude crystals of type I chlorogallium phthalocyanine sufficiently dissolved in 300 parts of sulfuric acid (concentration 97%) heated to 60 ° C. were ion-exchanged with 600 parts by mass of 25% aqueous ammonia. It was dripped in the mixed solution with 200 mass parts of water, and the hydroxygallium phthalocyanine crystal | crystallization was deposited. The crystals were collected by filtration, washed with ion exchange water, and then dried to obtain 8 parts by mass of a type I hydroxygallium phthalocyanine pigment.
Using 6 parts by weight of the obtained type I hydroxygallium phthalocyanine pigment together with 90 parts by weight of N, N-dimethylformamide and 350 parts by weight of glass spherical media having an outer diameter of 0.9 mm at 25 ° C. using a glass ball mill. Wet milled for 48 hours. At this time, the progress of the crystal conversion is monitored by measuring the absorption wavelength of the wet pulverization treatment liquid, and the maximum peak wavelength (λ _MAX ) in the spectral absorption spectrum of the hydroxygallium phthalocyanine pigment after the wet pulverization treatment in the wavelength region of 600 to 900 nm. Was 827 nm. The result is shown in FIG.

The specific hydroxygallium phthalocyanine pigment-1 was measured for an X-ray diffraction spectrum using CuKα characteristic X-rays. The Bragg angles (2θ ± 0.2 °) were 7.5 °, 9.9 °, 12.5 Diffraction peaks were shown at °, 16.3 °, 18.6 °, 25.1 °, and 28.3 °. The result is shown in FIG.
Furthermore, when the specific hydroxygallium phthalocyanine pigment-1 was observed using a transmission electron micrograph, it was confirmed that there were no particles having a particle size of 0.3 μm or more. A transmission electron micrograph at this time is shown in FIG.
In addition, the BET specific surface area of the specific hydroxygallium phthalocyanine pigment-1 was measured by a nitrogen substitution method using a BET specific surface area measuring instrument (manufactured by Shimadzu Corporation: Flow Soap II 2300), and was found to be 68.3 m ² / g. there were.

15 parts by mass of the specific hydroxygallium phthalocyanine pigment-1 thus prepared, 0.3 parts by mass of a specific resorcinarene compound (the above compound example-13), a vinyl chloride / vinyl acetate copolymer resin ( A mixture of 10 parts by mass of VMCH (manufactured by Nihon Unicar Co., Ltd.) and 300 parts by mass of n-butyl acetate was dispersed for 100 minutes using a 1 mmφ glass bead to obtain a coating solution for a charge generation layer.
This charge generation layer 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.

  Further, 4 parts by mass of N, N′-diphenyl-N, N′-bis (3-methylphenyl)-[1,1 ′] biphenyl-4,4′-diamine and the following structural formula (A1 A coating solution for a charge transport layer, in which 6 parts by mass of a bisphenol Z polycarbonate resin (viscosity average molecular weight 40,000) having a repeating structural unit represented by) is added to 60 parts by mass of tetrahydrofuran, is formed on the charge generation layer. Then, a charge transport layer having a film thickness of 21 μm was formed by drying at 130 ° C. for 40 minutes to produce an electrophotographic photosensitive member.

  The obtained electrophotographic photosensitive member was mounted on an image quality test apparatus in which a full color printer (manufactured by Xerox: Phaser 6250) having a contact charging device and an intermediate transfer device was modified, and the image quality of the output image was evaluated. Here, the ghost grade of the output image when the transfer voltage (VIDT) applied from the primary transfer member in contact with the electrophotographic photosensitive member was changed between 300 and 600 V was evaluated. For the ghost evaluation image, an arbitrary number of 15 mm square patterns are printed for one round of the electrophotographic photosensitive member, and then the entire halftone image is printed in the next cycle, and the ghost image that appears on the halftone image is displayed. evaluated. Magenta was used for printing. The halftone image was created with a pattern of 1 dot ON-3 dots OFF. The image was printed at a temperature of 20 ° C. and a humidity of 40%. The ghost was visually graded and measured as follows. The results are shown in Table 2.

Grade 0: Ghost is not visible at all Grade 1: Ghost appears to be extremely thin Grade 2: Ghost appears to be thin Grade 3: Ghost appears clearly Grade 4: Ghost appears dark Grade 5: Ghost appears extremely dark Of these grades If it is grade 2 or lower, it is a level (allowable level) that causes no problem in image quality. The results are shown in Table 2. In Table 2, “+” in the ghost grade column indicates a positive ghost, “−” indicates a negative ghost, and the first digit of the decimal point indicates an intermediate grade between the preceding and subsequent grades.

[Example 2]
In the same manner as in Example 1, an undercoat layer having a thickness of 20 μm was obtained on an aluminum substrate.
Next, a specific hydroxygallium phthalocyanine pigment having a maximum peak wavelength (λ _max ) in the range of 600 to 900 nm in the spectral absorption spectrum at 819 nm was prepared as follows.

(Preparation of specific hydroxygallium phthalocyanine pigment-2)
A specific hydroxygallium phthalocyanine pigment-2 was prepared in the same manner as in the preparation of the specific hydroxygallium phthalocyanine pigment-1 used in Example 1, except that the wet pulverization time was changed from 48 hours to 192 hours.
The specific hydroxygallium phthalocyanine pigment-2 obtained had a maximum peak wavelength (λ _max ) in the range of 600 to 900 nm of the spectral absorption spectrum of 819 nm.
Further, when X-ray diffraction spectrum using CuKα characteristic X-ray was measured for the specific hydroxygallium phthalocyanine pigment-2, the Bragg angle (2θ ± 0.2 °) was 7.5 °, 9.9 °, 12 Diffraction peaks were shown at .5 °, 16.3 °, 18.6 °, 25.1 °, and 28.3 °.
Furthermore, when the specific hydroxygallium phthalocyanine pigment-2 was observed using a transmission electron micrograph, it was confirmed that there were no particles having a particle size of 0.3 μm or more.
In addition, the BET specific surface area of the specific hydroxygallium phthalocyanine pigment-2 was measured by a nitrogen substitution method using a BET specific surface area measuring instrument (manufactured by Shimadzu Corporation: Flow Soap II 2300), and was found to be 78.6 m ² / g. there were.

15 parts by mass of the specific hydroxygallium phthalocyanine pigment-2 thus produced, 0.3 parts by mass of a specific resorcinarene compound (the above compound example-13), a vinyl chloride / vinyl acetate copolymer resin ( A mixture of 10 parts by mass of VMCH (manufactured by Nihon Unicar Co., Ltd.) and 300 parts by mass of n-butyl acetate was dispersed for 100 minutes using a 1 mmφ glass bead to obtain a coating solution for a charge generation layer.
This charge generation layer 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 1.21.

  Furthermore, 4 parts by mass of N, N′-diphenyl-N, N′-bis (3-methylphenyl)-[1,1 ′] biphenyl-4,4′-diamine and the following structural formula (B1 A charge transport layer coating solution prepared by adding 6 parts by mass of a bisphenol C polyacrylate resin (molecular weight 40,000: PAR) having a repeating structural unit represented by After forming and drying at 130 ° C. for 40 minutes, a 15 μm-thick charge transport layer was formed, and an electrophotographic photosensitive member was produced.

  The obtained electrophotographic photosensitive member is mounted on an image quality test apparatus in which a full color printer (manufactured by Xerox: Phaser 6250) having a contact charging device and an intermediate transfer device is remodeled. Evaluated. The results are shown in Table 2.

[Example 3]
In Example 1, except that the specific hydroxyl gallium phthalocyanine pigment-1 was replaced with the specific hydroxyl gallium phthalocyanine pigment-2 used in Example 2, an electrophotographic photoreceptor was prepared and evaluated in the same manner as in Example 1. It was. The results are shown in Table 2.

[Example 4]
In Example 3, an electrophotographic photoreceptor was prepared and evaluated in the same manner as in Example 3 except that the compound example-15 was used instead of the compound example-13 as the specific resorcinarene compound. The results are shown in Table 2.

[Comparative Example 1]
In Example 1, an electrophotographic photoreceptor was prepared and evaluated in the same manner as in Example 1 except that Compound Example-13 as the specific resorcinarene compound was not added. The results are shown in Table 3.

[Comparative Example 2]
In Example 3, an electrophotographic photoreceptor was prepared and evaluated in the same manner as in Example 3 except that Compound Example-13 as the specific resorcinarene compound was not added. The results are shown in Table 3.

[Comparative Example 3]
An electrophotographic photoreceptor was prepared and evaluated in the same manner as in Example 1 except that the specific hydroxygallium phthalocyanine pigment-1 was replaced with the hydroxygallium phthalocyanine pigment-3 shown below in Example 1. The results are shown in Table 3.

(Preparation of hydroxygallium phthalocyanine pigment-3)
A glass stirring tank having a stirring device together with 5 parts by mass of I-type hydroxygallium phthalocyanine pigment obtained in Example 1 (Preparation of specific hydroxygallium phthalocyanine pigment-1) together with 80 parts by mass of N, N-dimethylformamide. Used to stir at 25 ° C. for 48 hours to obtain crystals. Next, the obtained crystal was washed with acetone and dried by heating at 80 ° C. for 24 hours using a drier where light was blocked to obtain 5.5 parts by mass of hydroxygallium phthalocyanine pigment-3.
The obtained hydroxygallium phthalocyanine pigment-3 had a maximum peak wavelength (λ _max ) of 854 nm in the range of 600 to 900 nm in the spectral absorption spectrum.
Further, when an X-ray diffraction spectrum using CuKα characteristic X-ray was measured for this hydroxygallium phthalocyanine pigment-3, the Bragg angle (2θ ± 0.2 °) was 7.5 °, 9.9 °, 12. Diffraction peaks were shown at 5 °, 16.3 °, 18.6 °, 25.1 °, and 28.3 °.
Furthermore, when this hydroxygallium phthalocyanine pigment-3 was observed using a transmission electron micrograph, it was confirmed that particles having a particle size of 0.3 μm or more were present.
In addition, the BET specific surface area of this hydroxygallium phthalocyanine pigment-3 was measured by a nitrogen substitution method using a BET specific surface area meter (manufactured by Shimadzu Corporation: Flow Soap II 2300), and found to be 41.4 m ² / g. It was.

[Comparative Example 4]
An electrophotographic photoreceptor was prepared and evaluated in the same manner as in Example 1 except that the specific hydroxygallium phthalocyanine pigment-1 was replaced with the hydroxygallium phthalocyanine pigment-4 shown below in Example 1. The results are shown in Table 3.

(Preparation of hydroxygallium phthalocyanine pigment-4)
In Example 1 (Preparation of specific hydroxygallium phthalocyanine pigment-1), 350 parts by mass of glass spherical media having an outer diameter of 5.0 mm were used instead of 350 parts by mass of glass spherical media having an outer diameter of 0.9 mm. A hydroxygallium phthalocyanine pigment-4 was prepared in the same manner as the specific hydroxygallium phthalocyanine pigment-1, except that
The obtained hydroxygallium phthalocyanine pigment-4 had a maximum peak wavelength (λ _max ) in the range of 600 to 900 nm of the spectral absorption spectrum of 845 nm.
Further, when the X-ray diffraction spectrum of the hydroxygallium phthalocyanine pigment-4 using CuKα characteristic X-ray was measured, the Bragg angle (2θ ± 0.2 °) was 7.5 °, 9.9 °, 12. Diffraction peaks were shown at 5 °, 16.3 °, 18.6 °, 25.1 °, and 28.3 °.
Furthermore, when this hydroxygallium phthalocyanine pigment-4 was observed using a transmission electron micrograph, it was confirmed that particles having a particle diameter of 0.3 μm or more were present. A transmission electron micrograph at this time is shown in FIG.
In addition, the BET specific surface area of this hydroxygallium phthalocyanine pigment-4 was measured by a nitrogen substitution method using a BET specific surface area measuring instrument (manufactured by Shimadzu Corporation: Flow Soap II 2300), and was found to be 43.8 m ² / g. It was.

In Tables 2 and 3, what is described as the type of pigment is any one of the above-mentioned specific hydroxygallium phthalocyanine pigments -1, -2, and hydroxygallium phthalocyanine pigments -3, -4.
As apparent from Tables 2 and 3, in Examples 1 to 4, it was found that positive and negative ghosts were kept low and a good output image was obtained. On the other hand, in Comparative Examples 1 to 4, strong positive and negative ghosts appeared. More specifically, in Comparative Examples 1 to 4, in the high VIDT region, a strong negative ghost, which appears to be an influence of the transfer voltage applied by the transfer member, is seen, whereas in Examples 1 to 4, Even in a high VIDT region, the occurrence of negative ghost is suppressed and a good output image is obtained. For example, when VIDT is 550 V, in all of Examples 1 to 4, the ghost is in an allowable range, whereas in Comparative Examples 1 to 4, all of the values are out of the allowable level, and the occurrence of ghost is remarkable. I understand.
Furthermore, in Examples 1 to 4, the ghost grade is 2 or less (both positive and negative), the VIDT region is wide, and a stable and good output image is obtained. In 1-4, the VIDT area | region where a ghost grade becomes 2 or less is narrow, and it turns out that a favorable output image is not obtained stably.

1 is a schematic cross-sectional view showing a preferred embodiment of an electrophotographic photoreceptor of the present invention. 1 is a schematic cross-sectional view showing a preferred embodiment of an electrophotographic photoreceptor of the present invention. 1 is a schematic cross-sectional view showing a preferred embodiment of an electrophotographic photoreceptor of the present invention. 1 is a schematic cross-sectional view showing a preferred embodiment of an electrophotographic photoreceptor of the present invention. 1 is a schematic configuration diagram showing an embodiment of an image forming apparatus of the present invention. 1 is a schematic configuration diagram showing an embodiment of an image forming apparatus of the present invention. It is a schematic block diagram which shows other embodiment of the image forming apparatus of this invention. 1 is a schematic configuration diagram showing a preferred embodiment of a process cartridge of the present invention. 2 is an X-ray diffraction pattern of powder of specific hydroxygallium phthalocyanine pigment-1 used in Example 1. FIG. 2 is a spectral absorption spectrum of the specific hydroxygallium phthalocyanine pigment-1 used in Example 1. 2 is a transmission electron micrograph of the specific hydroxygallium phthalocyanine pigment-1 used in Example 1. FIG. 4 is a transmission electron micrograph of hydroxygallium phthalocyanine pigment-4 used in Comparative Example 4.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1a, 1b, 1c, 1d ... Electrophotographic photoreceptor 2 ... Conductive base | substrate 3 ... Photosensitive layer 4 ... Undercoat layer 5 ... Charge generation layer 6 ... Charge transport layer 7 ... Protective layer 8 ... Intermediate | middle layer 200a, 200b, 200c ... Image forming device 207 ... Electrophotographic photosensitive member 208 ... Charging device 209 ... Power supply 210 ... Exposure device 211 ... Developing device 212 ... Transfer device 212a ... Primary transfer member 212b ... Secondary transfer member 213 ... Cleaning device 214 ... Static eliminator 215 ... Fixing device 216 ... Mounting rail 217 ... Opening 218 for static elimination exposure ... Opening 300 for exposure ... Process cartridge 400 ... Housing 402a to 402d ... Charging rolls 401a to 401d ... Electrophotographic photoreceptors 402a to 402d ... Charging roll 403 ... Laser light source (exposure device)
404a to 404d Developing devices 405a to 405d Toner cartridge 406 Drive roll 407 Tension roll 408 Backup roll 409 Intermediate transfer belts 410a to 410d Primary transfer roll 411 Tray (transfer medium tray)
412 ... Transfer roll 413 ... Secondary transfer roll 414 ... Fixing rolls 415a to 415d ... Cleaning blade 416 ... Cleaning blade 500 ... Medium to be transferred

Claims (3)

An electrophotographic photosensitive member having a photosensitive layer on a substrate having at least a conductive surface,
The photosensitive layer contains a hydroxygallium phthalocyanine pigment having absorption at a maximum peak of 810 to 839 nm in the range of 600 to 900 nm of the spectral absorption spectrum, and a resorcinarene compound represented by the following general formula (1). An electrophotographic photosensitive member.
(In the formula, R ¹ represents a hydrogen atom, an alkyl group which may have a substituent, or an aryl group which may have a substituent, and R ² represents an aromatic which may have a substituent. R ² represents a hydrocarbon group or a heterocyclic group which may have a substituent, wherein R ² is a group in which a plurality of aromatic hydrocarbon groups are bonded, or a group in which a plurality of heterocyclic groups are bonded. May be good.)   The electrophotographic photosensitive member according to claim 1, 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 the electrostatic latent image An electrophotographic image forming apparatus comprising: a developing device that develops an image to form a toner image; and a transfer device that transfers the developed toner image to a transfer medium.   The electrophotographic photosensitive member according to claim 1, a charging device that charges the electrophotographic photosensitive member, an exposure device that exposes the charged electrophotographic photosensitive member to form an electrostatic latent image, and the electrostatic latent image A developing device that forms a toner image by developing, and at least one device selected from a cleaning device that cleans the electrophotographic photosensitive member, and is detachable from the main body of the electrophotographic image forming apparatus. To process cartridge.