JP2006267957A - Electrophotographic photoreceptor, composite body, manufacturing method for composite body, process cartridge, and electrophotographic device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electrophotographic photoreceptor which has sufficient sensitivity and can sufficiently suppress the generation of defects in picture quality due to fogging and a ghost. <P>SOLUTION: The electrophotographic photoreceptor has a conductive base and a photosensitive layer which is provided on the conductive base and contains a hydroxygallium phthalocyanine pigment having a maximum peak wavelength within a range of 810 to 839 nm in a spectral absorption spectrum in a wavelength range of 600 to 900 nm and a hydroxyketone compound expressed by formula (1) (where R<SP>1</SP>to R<SP>4</SP>represent hydrocarbon groups). <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an electrophotographic photosensitive member, a composite, a method for manufacturing the composite, a process cartridge, and an electrophotographic apparatus.

  In recent years, an electrophotographic apparatus is widely used in a copying machine, a laser beam printer, and the like because it can obtain a high printing quality at a high speed. As an electrophotographic photosensitive member (hereinafter, abbreviated as “photosensitive member” in some cases) used in this electrophotographic apparatus, those using various inorganic and organic photoconductive substances are known. Organic photoreceptors using a photoconductive material are widely used because they have advantages in terms of manufacturability and discardability at a lower cost than inorganic photoreceptors using an inorganic photoconductive material. In addition, the photoconductor structure is changed from a single layer structure to a charge transfer type complex structure or a function separation type photoconductor in which a charge generation layer containing a charge generation material and a charge transport layer containing a charge transport material are laminated. The performance of photoconductors is being improved.

  In the function-separated type photoreceptor, an undercoat layer is formed as necessary on a conductive support having at least a conductive surface, and a photosensitive layer comprising a charge generation layer and a charge transport layer is formed thereon. Manufactured by. The charge generation layer in this function-separated type photoreceptor is formed by a method of vacuum-depositing a charge generation material such as a phthalocyanine pigment or an azo pigment, or a method of forming a coating liquid in which the charge generation material is dispersed in a binder resin. The latter method is generally used because it is excellent in productivity and cost.

  As the charge generation material, a phthalocyanine pigment which is inexpensive and excellent in manufacturability and safety is preferably used, and many reports on its crystal form and electrophotographic characteristics have been made. Among them, an electrophotographic photoreceptor using a hydroxygallium phthalocyanine pigment described in Patent Document 1 below as a charge generation material has higher sensitivity than a photoreceptor using other charge generation materials due to its high charge generation capability. Tend to be able to get.

  When forming a charge generation layer by forming a coating solution in which these charge generation materials are dispersed in a binder resin, first, the charge generation material is dispersed in a solution in which the binder resin is dissolved in an organic solvent, and the resulting coating solution is obtained. The charge generation layer can be formed by coating the conductive layer on the conductive support or the undercoat layer and drying. It has been found that the state of the charge generating material in the coating solution has a great influence on the electrical characteristics and image characteristics of the electrophotographic photoreceptor. Here, the state of the charge generation material in the coating solution that affects the characteristics of the electrophotographic photosensitive member includes the dispersion state of the charge generation material in the coating solution and the crystalline state of the charge generation material itself (molecular arrangement). ).

  Regarding the dispersion state of the charge generation material, for example, in the spectral absorption spectrum of the coating liquid, a method for evaluating the dispersibility by the ratio of the absorbance at a wavelength without absorption inherent in the charge generation material and the absorbance at an arbitrary peak wavelength is proposed. (See Patent Document 2). The same document discloses preferable dispersibility values for specific phthalocyanine pigments.

  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 differ greatly when the crystal types are different. As for the crystal type of the phthalocyanine pigment, for example, crystal types such as α-type, β-type, π-type, γ-type, and X-type are known for metal-free phthalocyanine crystals.

  As for 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 CuKα characteristic X-ray is 7.5 °, 9.9 °, Highly sensitive hydroxygallium phthalocyanine pigment (V-type hydroxygallium phthalocyanine pigment) having diffraction peaks at 12.5 °, 16.3 °, 18.6 °, 25.1 °, and 28.3 °, and the same It has been reported that an electrophotographic photoreceptor is excellent in photosensitivity, repeatability, and environmental stability (see, for example, Non-Patent Document 1, Patent Documents 1 and 3).

  Further, an electrophotographic photosensitive member in which a β-hydroxyketone compound is contained in a photosensitive layer together with a hydroxygallium phthalocyanine pigment has been proposed (for example, see Patent Document 4).

Japanese Patent Laid-Open No. 5-263007 JP-A-10-97088 JP 7-53892 A JP 2000-250237 A Journal of Imaging Science and Technology, Vol. 40, no. 3, May / June, 249 (1996)

  An electrophotographic photoreceptor using such a hydroxygallium phthalocyanine pigment as a constituent material of the photosensitive layer can obtain high sensitivity as described above. However, on the other hand, photoreceptors using hydroxygallium phthalocyanine pigments tend to cause local increase in dark decay during repeated use, decrease in chargeability, and decrease in chargeability due to local charge injection. There is a problem that fog is likely to occur in the blank paper portion of the image. Although the mechanism of the decrease in chargeability and the increase in dark decay has not been clarified, there is a so-called trap site that traps charges in the photosensitive layer, which generates charges (free carriers) by thermal excitation or the like. Therefore, the present inventors infer that the chargeability is lowered and image quality defects such as fogging are caused.

  Furthermore, an electrophotographic photosensitive member using a hydroxygallium phthalocyanine pigment as a constituent material of the photosensitive layer has a phenomenon called so-called ghost in which the charge generated by exposure tends to remain in the photosensitive layer, and the exposure history in the previous cycle appears in the next cycle. It has a problem that it is likely to occur. For example, in the case of an electrophotographic apparatus in which a function-separated type photoconductor having a photosensitive layer composed of a charge generation layer and a charge transport layer is negatively charged and developed by a reversal development method, it is generated by image exposure after the charging step. A part of the generated holes are accumulated in the charge generation layer, and the holes accumulated in the charge generation layer immediately after the charging process of the next cycle move to the surface of the charge transport layer to reduce the surface potential, A so-called positive ghost phenomenon occurs in which the image of the previous cycle appears darkly.

  Among these problems, as a method for suppressing the decrease in chargeability and the occurrence of fogging, for example, a β-hydroxyketone compound as described in Patent Document 4 is contained in the photosensitive layer together with the hydroxygallium phthalocyanine pigment. A method is being tried. However, in the electrophotographic photoreceptor described in Patent Document 4, a portion where charge injection is likely to occur locally occurs on the photoreceptor due to the presence of coarse particles or pigment aggregates of hydroxygallium phthalocyanine pigment. Therefore, it is difficult to sufficiently suppress the occurrence of image quality defects due to fog. Further, the electrophotographic photosensitive member described in Patent Document 4 still has a problem that positive ghosts are still likely to occur.

  The present invention has been made in view of the above-described problems of the prior art, and has sufficient sensitivity and can sufficiently suppress the occurrence of image quality defects due to fog and ghost, and the electrophotographic photosensitive member It is an object of the present invention to provide a process cartridge and an electrophotographic apparatus using the apparatus. Another object of the present invention is to provide a composite used as a constituent material of the electrophotographic photosensitive member of the present invention and a method for producing the same.

［式（１）中、Ｒ^１、Ｒ^２、Ｒ^３及びＲ^４は、それぞれ独立に置換基を有していてもよい炭素数１〜１０の炭化水素基を示す。なお、Ｒ^１とＲ^２、及び、Ｒ^３とＲ^４は、互いに結合して環を形成していてもよい。］ In order to achieve the above object, the present invention is provided on a conductive support and the conductive support, and has a maximum peak in a range of 810 to 839 nm in a spectral absorption spectrum in a wavelength region of 600 to 900 nm. An electrophotographic photoreceptor comprising a hydroxygallium phthalocyanine pigment having a wavelength and a photosensitive layer containing a hydroxyketone compound represented by the following general formula (1) is provided.

[In formula (1), R ¹ , R ² , R ³ and R ⁴ each independently represent a hydrocarbon group having 1 to 10 carbon atoms which may have a substituent. R ¹ and R ² , and R ³ and R ⁴ may be bonded to each other to form a ring. ]

  Usually, in the phthalocyanine pigment, the interaction between the phthalocyanine molecules changes depending on the molecular arrangement in the crystal, and as a result, the state of the molecular arrangement is reflected in the spectral absorption spectrum. Here, in an X-ray diffraction pattern using CuKα characteristic X-rays, Bragg angles (2θ ± 0.2 °) 7.5 °, 9.9 °, 12.5 °, 16.3 °, 18.6 ° The conventional V-type hydroxygallium phthalocyanine pigments having diffraction peaks at 25.1 ° and 28.3 ° usually have a peak wavelength in the range of 840 to 870 nm, suggesting the existence of strong intermolecular interactions. The This means that there are many sites (sites) where charges can remain in the crystal. The unstable sites present in these crystals easily trap (charge) the charge generated by image exposure and easily release the captured charge. Therefore, when a hydroxygallium phthalocyanine pigment having a large number of such trap sites is contained in the photosensitive layer of the electrophotographic photosensitive member, it causes a decrease in local chargeability and an increase in dark decay, and image quality defects such as fogging are caused. Presumed to be more likely to occur. In addition, when there are a large number of such trap sites, it is assumed that charges generated by image exposure in the previous cycle are likely to remain in the photosensitive layer, and ghosts are likely to occur in the next cycle.

  In contrast, the hydroxygallium phthalocyanine pigment used in the electrophotographic photoreceptor of the present invention has a maximum peak wavelength in the range of 810 to 839 nm in the spectral absorption spectrum in the wavelength range of 600 to 900 nm. It is suggested that the intermolecular interaction is small compared to the gallium phthalocyanine pigment. For this reason, it is assumed that the number of trap sites present in the crystal is also reduced. When the hydroxyketone compound represented by the above general formula (1) is used together with such a hydroxygallium phthalocyanine pigment, the hydroxyketone compound functions as an acceptor in the photosensitive layer, and draws out the charges trapped at the trap site. The electronic state can be fixed. In particular, the above-mentioned specific hydroxygallium phthalocyanine pigment is sufficiently suppressed in the formation of coarse particles and pigment aggregates and is present in the photosensitive layer in a highly dispersed state, so that the efficiency of the hydroxyketone compound to extract charge from the hydroxygallium phthalocyanine pigment. Is considered to improve dramatically. As a result, the number of trap sites that capture charges in the photosensitive layer is extremely small, charging stability and stabilization of dark decay are realized during repeated use, and image quality defects such as fog are sufficiently suppressed. It is inferred that In addition, the use of the above-mentioned hydroxygallium phthalocyanine pigment has a small number of original trap sites and the action of trap sites is suppressed by coexistence with the hydroxyketone compound, so that the charge generated by image exposure in the previous cycle is reduced. It is presumed that it is difficult to remain in the photosensitive layer, and as a result, generation of ghost in the next cycle is sufficiently suppressed.

  In addition, the said maximum peak wavelength means the peak wavelength which shows the maximum light absorbency in the case where several peaks exist in the spectral absorption spectrum in the wavelength range of 600-900 nm.

  In the electrophotographic photoreceptor of the present invention, the spectral absorption spectrum of the photosensitive layer preferably has an absorption peak wavelength in the range of 810 to 839 nm.

  When the spectral absorption spectrum of the photosensitive layer has an absorption peak wavelength in the above range, the molecular interaction of the hydroxygallium phthalocyanine pigment is small in the photosensitive layer, and the trap sites are sufficiently reduced. Stabilization of chargeability and dark decay during use can be realized, and image quality defects such as fog can be sufficiently suppressed.

The hydroxygallium phthalocyanine pigment preferably has a particle size of 0.3 μm or more per observation region of 30 μm ² in the transmission electron microscope observation image.

  Such hydroxygallium phthalocyanine pigments can exhibit better dispersibility in the photosensitive layer. In addition, such a hydroxygallium phthalocyanine pigment has a large surface area and fewer trap sites included in the crystal. Therefore, the probability that the trap site is exposed to the crystal surface of the pigment is increased, and it is considered that the trap site is efficiently stabilized by the hydroxyketone compound. Furthermore, when such a hydroxygallium phthalocyanine pigment is contained in the photosensitive layer, there is no hydroxygallium phthalocyanine pigment having a particle size specifically larger than the film thickness of the photosensitive layer, so a coating solution for forming the photosensitive layer is prepared. In doing so, it is possible to reduce the share and dispersion time given by dispersion. By reducing the share given to the hydroxygallium phthalocyanine pigment from the outside by dispersion, it is possible to sufficiently prevent the increase of trap sites that may be caused by minute distortions in the crystalline state, and the crystal of the hydroxygallium phthalocyanine pigment. It is possible to prevent the mold from changing. As a result, an electrophotographic photoreceptor comprising the above-mentioned hydroxygallium phthalocyanine pigment in the photosensitive layer together with the above-mentioned hydroxyketone compound provides more sufficient sensitivity and more sufficiently suppresses the occurrence of image quality defects due to fogging and ghosting. can do.

  Further, the hydroxygallium phthalocyanine pigment has diffraction peaks at Bragg angles (2θ ± 0.2 °) of 7.5 ° and 28.3 ° in an X-ray diffraction spectrum using CuKα characteristic X-rays. It is preferable.

  An electrophotographic photoreceptor comprising the above-described hydroxygallium phthalocyanine pigment having a diffraction peak in the photosensitive layer together with the above hydroxyketone compound provides more sufficient sensitivity, and more sufficiently causes image quality defects due to fogging and ghosting. Can be suppressed.

  The hydroxyketone compound is preferably 1- (2-cyclohexanonyl) cyclohexanol.

  Such a hydroxyketone compound has excellent acceptor properties, is excellent in the effect of stabilizing the electronic state of a hydroxygallium phthalocyanine pigment, and is excellent in sensitivity characteristics. Therefore, an electrophotographic photosensitive member using such a compound has more sufficient sensitivity. As a result, image quality defects caused by fogging and ghosting can be more sufficiently suppressed.

  Further, the photosensitive layer preferably contains a complex of the hydroxygallium phthalocyanine pigment and the hydroxyketone compound.

  According to such an electrophotographic photosensitive member, by adding a composite of a hydroxygallium phthalocyanine pigment and a hydroxyketone compound to the photosensitive layer, charging characteristics, photosensitivity and low dark decay characteristics are further improved, fogging, ghosting, etc. The occurrence of image quality defects can be more sufficiently suppressed.

  The reason why such an effect is obtained is not necessarily clear, but the present inventors speculate as follows. That is, it is considered that the hydroxygallium phthalocyanine pigment and the hydroxyketone compound form a complex with each other, thereby improving the efficiency of the hydroxyketone compound to extract charges from the trap site of the hydroxygallium phthalocyanine pigment. Furthermore, when the composite is dispersed and held in the binder resin, the hydroxyketone compound acts effectively through the interface between the hydroxygallium phthalocyanine pigment and the binder resin. It is conceivable that the effect of improving the effect and the effect of reducing the trap sites existing on the pigment surface are further improved. The present inventors consider that the above-described effects can be obtained. In addition, when the photosensitive layer contains a complex of a hydroxygallium phthalocyanine pigment and a hydroxyketone compound, the amount of the hydroxyketone compound used can be reduced, and the dispersibility of the complex can be further improved. The present inventors consider that this is one of the factors that can achieve this effect.

  Here, in the X-ray diffraction spectrum using CuKα characteristic X-ray, the above composite has a Bragg angle (2θ ± 0.2 °) of 6.9 °, 13.2 to 14.2 °, 16.5 °, Type I hydroxygallium phthalocyanine pigments having diffraction peaks at 26.0 ° and 26.4 °, or 7.0 °, 13.4 °, 16.6 °, 26.0 ° and 26.7 °, or Wet grinding treatment of a mixture containing a V-type hydroxygallium phthalocyanine pigment having diffraction peaks at Bragg angles (2θ ± 0.2 °) of 7.5 ° and 28.3 °, the hydroxyketone compound, and a predetermined solvent It is preferable that it is obtained by doing.

  According to such an electrophotographic photoreceptor, the photosensitive layer contains a composite obtained by wet-grinding the above mixture, whereby charging characteristics, photosensitivity, and low dark decay characteristics are further improved. Generation of image quality defects such as ghosts can be more sufficiently suppressed.

  The reason why such an effect is obtained is not necessarily clear, but the present inventors speculate as follows. That is, the wet pulverization treatment sufficiently combines a hydroxyketone compound with a hydroxygallium phthalocyanine pigment that has been converted into a crystal form that exhibits better performance as a photoconductive material for an electrophotographic photosensitive member and has been refined. And a composite having excellent dispersibility and electrophotographic characteristics is obtained. In the composite thus obtained, since the hydroxyketone compound coexists in the crystal conversion of the pigment by the wet pulverization treatment, the hydroxyketone compound is dispersed to the inside of the crystal of the hydroxygallium phthalocyanine pigment. It is considered that the above-described effects can be obtained because the charge can be drawn in advance not only from the crystal surface but also from trap sites existing inside the crystal.

［式（１）中、Ｒ^１、Ｒ^２、Ｒ^３及びＲ^４は、それぞれ独立に置換基を有していてもよい炭素数１〜１０の炭化水素基を示す。なお、Ｒ^１とＲ^２、及び、Ｒ^３とＲ^４は、互いに結合して環を形成していてもよい。］ The present invention also relates to a composite used as a constituent material of an electrophotographic photosensitive member, and a hydroxygallium phthalocyanine pigment having a maximum peak wavelength in a range of 810 to 839 nm in a spectral absorption spectrum in a wavelength range of 600 to 900 nm; Provided is a complex obtained by complexing a hydroxyketone compound represented by the following general formula (1).

[In formula (1), R ¹ , R ² , R ³ and R ⁴ each independently represent a hydrocarbon group having 1 to 10 carbon atoms which may have a substituent. R ¹ and R ² , and R ³ and R ⁴ may be bonded to each other to form a ring. ]

  When such a composite is used as a constituent material of an electrophotographic photosensitive member, as described above, it has sufficient charging characteristics, light sensitivity, and low dark decay characteristics, and sufficiently suppresses the occurrence of image quality defects such as fogging and ghosting. An electrophotographic photosensitive member that can be obtained can be obtained.

［式（１）中、Ｒ^１、Ｒ^２、Ｒ^３及びＲ^４は、それぞれ独立に置換基を有していてもよい炭素数１〜１０の炭化水素基を示す。なお、Ｒ^１とＲ^２、及び、Ｒ^３とＲ^４は、互いに結合して環を形成していてもよい。］ The present invention further includes Bragg angles (2θ ± 0.2 °) of 6.9 °, 13.2 to 14.2 °, 16.5 °, 26.0 in the X-ray diffraction spectrum using CuKα characteristic X-rays. Type I hydroxygallium phthalocyanine pigment having diffraction peaks at ° and 26.4 °, or 7.0 °, 13.4 °, 16.6 °, 26.0 ° and 26.7 °, or Bragg angle ( 2θ ± 0.2 °) V-type hydroxygallium phthalocyanine pigment having diffraction peaks at 7.5 ° and 28.3 °, a hydroxyketone compound represented by the following general formula (1), and a predetermined solvent A hydroxygallium phthalate having a maximum peak wavelength in a range of 810 to 839 nm in a spectral absorption spectrum in a wavelength region of 600 to 900 nm, comprising a wet pulverization treatment step of wet pulverizing a mixture It provides a method for producing a complex of a cyanine pigment and the hydroxy ketone compounds.

[In formula (1), R ¹ , R ² , R ³ and R ⁴ each independently represent a hydrocarbon group having 1 to 10 carbon atoms which may have a substituent. R ¹ and R ² , and R ³ and R ⁴ may be bonded to each other to form a ring. ]

  The composite obtained by this composite manufacturing method has sufficient charging characteristics, photosensitivity and low dark decay characteristics when used as a constituent material of an electrophotographic photosensitive member, and is free from image quality defects such as fogging and ghosting. An electrophotographic photosensitive member capable of sufficiently suppressing the generation can be obtained.

  Here, the method for producing a composite according to the present invention further includes an acid pasting treatment step in which the crude gallium phthalocyanine is subjected to an acid pasting treatment to obtain the above-mentioned type I hydroxygallium phthalocyanine pigment before the wet pulverization treatment step. Is preferred.

  According to such a method for producing a composite, the type I hydroxygallium phthalocyanine pigment obtained by the acid pasting process is subjected to the wet pulverization process, thereby shortening the time in the wet pulverization process. It becomes possible, and the composite_body | complex of this invention can be obtained efficiently.

  The reason why such an effect is obtained is that the crystal structure of the type I hydroxygallium phthalocyanine pigment obtained by the acid pasting treatment step is excellent as a photoconductive substance for an electrophotographic photoreceptor by the wet grinding treatment step. A structure that is more suitable for conversion into a crystal form that exhibits excellent performance, and a structure that is less likely to form coarse particles or aggregates even in the presence of a hydroxyketone compound in the wet pulverization process. This is probably because of this.

  The present invention also provides the electrophotographic photosensitive member of the present invention, charging means for charging the electrophotographic photosensitive member, and developing the electrostatic latent image formed on the electrophotographic photosensitive member with toner to form a toner image. There is provided a process cartridge comprising: a developing unit for forming; and at least one selected from the group consisting of a cleaning unit for removing toner remaining on the surface of the electrophotographic photosensitive member.

  The present invention further includes the electrophotographic photosensitive member of the present invention, a charging unit for charging the electrophotographic photosensitive member, an exposure unit for forming an electrostatic latent image on the charged electrophotographic photosensitive member, And developing means for developing the electrostatic latent image with toner to form a toner image, and transfer means for transferring the toner image from the electrophotographic photosensitive member to a transfer target. An electrophotographic apparatus is provided.

  These process cartridges and electrophotographic apparatuses have sufficient charging characteristics, light sensitivity, and low dark decay characteristics by including the electrophotographic photosensitive member of the present invention, and sufficiently generate image quality defects such as fogging and ghosting. Can be suppressed.

  According to the present invention, it is possible to provide an electrophotographic photosensitive member having sufficient sensitivity and capable of sufficiently suppressing occurrence of image quality defects due to fogging and ghosting. In addition, according to the present invention, it is possible to provide a composite capable of obtaining the electrophotographic photosensitive member of the present invention having the above characteristics and a method for producing the same by using as a constituent material of the electrophotographic photosensitive member. Furthermore, according to the present invention, it is possible to provide a process cartridge and an electrophotographic apparatus that have sufficient sensitivity and can sufficiently suppress the occurrence of image quality defects due to fogging and ghosting.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. In the following description, the same or corresponding parts are denoted by the same reference numerals, and redundant description is omitted.

(Electrophotographic photoreceptor)
FIG. 1A is a schematic cross-sectional view showing a first embodiment of the electrophotographic photosensitive member of the present invention. The electrophotographic photoreceptor 100 shown in FIG. 1A is a laminated type in which functions are separated into a layer containing a charge generation material (charge generation layer 1a) and a layer containing a charge transport material (charge transport layer 2). The photosensitive layer 6 a is provided, and has a structure in which a charge generation layer 1 a and a charge transport layer 2 are sequentially laminated on a conductive support 3. The charge generation layer 1a contains a hydroxygallium phthalocyanine pigment and a hydroxyketone compound.

  First, the hydroxygallium phthalocyanine pigment and the hydroxyketone compound contained in the charge generation layer 1a of the electrophotographic photoreceptor 100 of this embodiment will be described.

［式（２）中、Ｘ^１１、Ｘ^１２、Ｘ^１３及びＸ^１４はそれぞれ独立に、塩素原子又は臭素原子を示し、ｃ、ｄ、ｅ及びｆはそれぞれ独立に、０〜４の整数を示す。］ The hydroxygallium phthalocyanine pigment used in the present embodiment is represented by the following general formula (2), and has a maximum peak wavelength in the range of 810 to 839 nm in the spectral absorption spectrum in the wavelength range of 600 to 900 nm. It is what you have.

[In the formula (2), X ¹¹ , X ¹² , X ¹³ and X ¹⁴ each independently represent a chlorine atom or a bromine atom, and c, d, e and f each independently represent an integer of 0 to 4. . ]

  In this way, by shifting the maximum peak wavelength of the spectral absorption spectrum to a shorter wavelength side than the conventional one, a fine hydroxygallium phthalocyanine pigment in which the crystal arrangement of the pigment particles is suitably controlled is obtained. When used as a constituent material, it is possible to obtain excellent dispersibility and sufficient sensitivity, chargeability and dark decay characteristics.

The hydroxygallium phthalocyanine pigment used in the present embodiment preferably has a volume average particle diameter in a specific range and a BET specific surface area in a specific range. Specifically, the volume average particle size is preferably 0.20 μm or less, more preferably 0.01 to 0.1 μm, and particularly preferably 0.01 to 0.08 μm. On the other hand, it is preferable that a BET specific surface area of ^{45 m} 2 / g or more, more preferably ^{50 m} 2 / g or more, and particularly preferably 55~120m ² / g.

When the volume average particle diameter of the pigment is larger than 0.20 μm, or when the specific surface area value is less than 45 m ² / g, the pigment particles are coarsened or aggregates of the pigment particles are formed, Defects tend to easily occur in the characteristics such as dispersibility, photosensitivity, charging characteristics, and dark decay characteristics when used as a material for a photographic photosensitive member, thereby tending to cause image quality defects such as fog. That is, when the above-mentioned fine pigment and hydroxyketone compound are dispersed and held in the binder resin, the dispersibility of the pigment with respect to the binder resin is further improved, so that variations in sensitivity, charging characteristics, and dark attenuation characteristics can be obtained. In addition to being able to reduce the image quality, it is possible to more reliably prevent occurrence of image quality defects such as fogging and ghosting, and to obtain stable image quality over a long period of time.

Further, it is preferable that the hydroxygallium phthalocyanine pigment does not contain particles having a particle size of 0.3 μm or more as much as possible. More specifically, the hydroxygallium phthalocyanine preferably has a particle size of 0.3 μm or more per observation region of 30 μm ² in the transmission electron microscope observation image. When particles having a particle size of 0.3 μm or more are present at a ratio of more than 1 per 30 μm ^{2 of the} observation region, the particles of hydroxygallium phthalocyanine may be coarsened or particle aggregates may be formed. As the number of traps increases, image quality defects such as fogging tend to occur. For the same reason, it is more preferable that the hydroxygallium phthalocyanine has a particle diameter of 0.2 μm or more per observation region of 30 μm ² in the transmission electron microscope observation image.

  The hydroxygallium phthalocyanine pigment has diffraction peaks at 7.5 ° and 28.3 ° of the Bragg angle (2θ ± 0.2 °) in the X-ray diffraction spectrum using CuKα characteristic X-ray. And preferably have diffraction peaks at 7.5 °, 9.9 °, 12.5 °, 16.3 °, 18.6 °, 25.1 °, and 28.3 °. .

  Further, the hydroxygallium phthalocyanine pigment may be subjected to a surface treatment from the viewpoint of improving dispersibility as long as the maximum peak wavelength is maintained so as to satisfy the above conditions. Although it does not specifically limit as a surface treating agent, For example, a coupling agent etc. can be used.

  Examples of the coupling agent include vinyltrimethoxysilane, γ-methacryloxypropyl-tris (β-methoxyethoxy) silane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, and γ-glycidoxypropyltrimethoxy. Silane, vinyltriacetoxysilane, γ-mercaptopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, N-β- (aminoethyl) -γ-aminopropyltrimethoxysilane, N-β- (aminoethyl) -γ -Aminopropylmethylmethoxysilane, N, N-bis (β-hydroxyethyl) -γ-aminopropyltriethoxysilane, γ-chloropropyltrimethoxysilane, vinyltriethoxysilane, vinyltris (2-methoxyethoxysilane), 3 -Methacryloxypro Rutrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, N-2- (aminoethyl) -3-aminopropyltrimethoxysilane, N-2- (Aminoethyl) -3-aminopropylmethyldimethoxysilane, 3-aminopropyltriethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-chloropropyltrimethoxysilane, etc. A silane coupling agent is mentioned. 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 Organic zirconium compounds such as zirconium naphthenate, zirconium laurate, zirconium stearate, zirconium isostearate, methacrylate zirconium butoxide, stearate zirconium butoxide, isostearate zirconium butoxide and the like can be used. Further, 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 be used.

  As a method for obtaining the above-mentioned hydroxygallium phthalocyanine pigment, in an X-ray diffraction spectrum using CuKα characteristic X-ray, Bragg angle (2θ ± 0.2 °) 6.9 °, 13.2-14.2 °, 16 Type I hydroxygallium phthalocyanine having diffraction peaks at .5 °, 26.0 ° and 26.4 °, or 7.0 °, 13.4 °, 16.6 °, 26.0 ° and 26.7 ° Examples include a production method in which a pigment is crystallized by wet-grinding. The wet pulverization treatment can be performed by a pulverizer using a spherical medium having an outer diameter of 0.1 to 3.0 mm. Here, the amount of media used is set to 50 parts by mass or more with respect to 1 part by mass of the hydroxygallium phthalocyanine pigment, and the wet pulverization time is determined by measuring the absorption wavelength of the hydroxygallium phthalocyanine pigment in the pulverization process. Can do. For example, in the wet pulverization treatment, the crystalline gallium phthalocyanine pigment after the wet pulverization treatment has a crystal conversion state such that the spectral absorption spectrum in the wavelength region of 600 to 900 nm has a maximum peak wavelength in the range of 810 to 839 nm. Can be determined by monitoring the absorption wavelength of the wet pulverization treatment liquid.

  In an X-ray diffraction spectrum using CuKα characteristic X-rays used as a raw material in such a production method, Bragg angles (2θ ± 0.2 °) of 6.9 °, 13.2-14.2 °, 16.5 Type I hydroxygallium phthalocyanine pigments having diffraction peaks at °, 26.0 ° and 26.4 °, or 7.0 °, 13.4 °, 16.6 °, 26.0 ° and 26.7 ° It can be obtained by a conventionally known method. An example is shown below.

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

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

  The hydroxygallium phthalocyanine pigment used in the present embodiment can be obtained by wet-grinding the I-type hydroxygallium phthalocyanine pigment obtained by the acid pasting treatment together with a solvent to convert the crystal.

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

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

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

  Although the amount of the media used varies depending on the apparatus used, it is preferably 50 parts by mass or more and 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.

  Moreover, in said wet grinding process, it is preferable that the usage-amount of a solvent is 5-50 mass parts with respect to 1 mass part of I type hydroxygallium phthalocyanine, and it is more preferable that it is 10-30 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.

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

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

  The progress of pigment crystal conversion in the wet pulverization process is greatly affected by the scale of the wet pulverization process, the stirring speed, the media material, etc., but the hydroxygallium phthalocyanine pigment after the wet pulverization process has a wavelength range of 600 to 900 nm. The wet pulverization treatment time is determined while monitoring the crystal conversion state by measuring the absorption wavelength of the wet pulverization treatment liquid so that the maximum peak wavelength is in the range of 810 to 839 nm in the spectral absorption spectrum at It is preferable to continue until the crystal is converted. 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 the wet pulverization treatment apparatus, and acetone, ethyl acetate, etc. The method of measuring the solution diluted with the solvent by the liquid cell method using a spectrophotometer is mentioned.

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

  Next, examples of the hydroxyketone compound used in the present embodiment include compounds represented by the following formulas (3-1) to (3-10). In addition, a hydroxyketone compound is not limited to these compounds, A well-known thing can be especially used without a restriction | limiting. Further, in the following formulas (3-1) to (3-10), those without terminal description represent a methyl group.

  Among these, 1- (2-cyclohexanonyl) cyclohexanol represented by the general formula (3-1) is preferable. In addition, a hydroxy ketone compound can be used individually by 1 type or in combination of 2 or more types.

  Next, each component of the electrophotographic photoreceptor 100 will be described in detail.

  Examples of the conductive support 3 include those made of metal such as aluminum, copper, iron, zinc and nickel; on a substrate such as a polymer sheet, paper, plastic and glass, aluminum, copper, gold, silver and platinum Conductive treatment by depositing a metal such as palladium, titanium, nickel-chromium, stainless steel, copper-indium; Conductive treatment by depositing a conductive metal compound such as indium oxide or tin oxide on the substrate. Conductive treatment by laminating a metal foil on the substrate; carbon black, indium oxide, tin oxide-antimony oxide powder, metal powder, copper iodide, etc. are dispersed in a binder resin, The thing etc. which carried out the conductive process by apply | coating to are mentioned. The shape of the conductive support 3 may be any of a drum shape, a sheet shape, and a plate shape.

  When a metal pipe substrate is used as the conductive support 3, the surface thereof may remain as it is, but in advance, mirror cutting, etching, anodizing, rough cutting, centerless grinding, sand blasting, wet honing, coloring treatment It is preferable to roughen the substrate surface by a surface treatment such as In this way, by roughening the surface of the substrate, it is possible to prevent grain-like density spots due to interference light in the photoconductor that may occur when a coherent light source such as a laser beam is used.

  The charge generation layer 1a is a layer containing the hydroxygallium phthalocyanine pigment as a charge generation material, the hydroxyketone compound, and a binder resin.

  The 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 and vinyl chloride-vinyl acetate copolymer are preferably used. These binder resins can be used singly or in combination of two or more.

  The content of the hydroxyketone compound in the charge generation layer 1a is preferably 0.01 to 20 parts by mass, more preferably 0.1 to 15 parts by mass with respect to 100 parts by mass of the hydroxygallium phthalocyanine pigment. It is especially preferable that it is 0.2-10 mass parts. If the content of the hydroxyketone compound is less than 0.01 parts by mass, the effect of suppressing the occurrence of image quality defects such as fogging tends to be insufficient. On the other hand, when the content of the hydroxyketone compound exceeds 20 parts by mass, the hydroxyketone compound is not sufficiently dissolved in the charge generation layer forming coating solution for forming the charge generation layer 1a, and the uniform charge generation layer 1a is formed. Tends to be difficult to form.

  The compounding ratio (mass ratio) of the hydroxygallium phthalocyanine pigment and the binder resin in the charge generation layer 1a is preferably 10: 1 to 1:10, more preferably 8: 2 to 3: 7. When the blending amount of the hydroxygallium phthalocyanine pigment exceeds 10 times the blending amount of the binder resin, the dispersibility of the pigment in the dispersion used in the production process of the electrophotographic photosensitive member tends to be insufficient. If the blending amount of the binder resin is less than 1/10, the sensitivity of the electrophotographic photosensitive member tends to be insufficient.

  Furthermore, the charge generation layer 1a may contain a charge generation material other than the hydroxygallium phthalocyanine pigment described above. Here, examples of other charge generation materials contained in the charge generation layer 1a include azo pigments, perylene pigments, and condensed aromatic pigments. In the present embodiment, it is preferable to contain a metal-containing or metal-free phthalocyanine, and in particular, a hydroxygallium phthalocyanine pigment other than the above-mentioned hydroxygallium phthalocyanine pigment, a chlorogallium phthalocyanine pigment, a dichlorotin phthalocyanine pigment, or an oxytitanyl phthalocyanine pigment. It is preferable to contain. Further, the content ratio of these other charge generation materials is preferably 50% by mass or less based on the total amount of solids contained in the charge generation layer 1a.

  When another layer such as the charge transport layer 2 is further formed on the charge generation layer 1a, the charge generation layer 1a is not dissolved or swollen by the solvent used in the coating solution. The combination of the binder resin of the charge generation layer 1a and the solvent of the coating solution applied onto the charge generation layer 1a is preferably selected as appropriate. The binder resin of the charge generation layer 1a and the binder resin of the charge transport layer 2, which will be described later, are preferably used in combination with each other having a refractive index close to each other. The difference is preferably 1 or less. When the binder resins having similar refractive indexes are used in combination, the reflection of light at the interface between the charge generation layer 1a and the charge transport layer 2 is suppressed, and the interference fringe prevention effect tends to be improved.

  The charge generation layer 1a can be formed using a coating solution for forming a charge generation layer in which a hydroxygallium phthalocyanine pigment and a hydroxyketone compound are dispersed in a solution in which a binder resin is dissolved in a predetermined organic solvent. Dispersion can be performed using a sand mill, colloid mill, attritor, dyno mill, jet mill, coball mill, roll mill, ultrasonic disperser, gorin homogenizer, microfluidizer, optimizer, milder, and the like. As the organic solvent, those capable of dissolving the binder resin can be used. For example, alcohol-based, aromatic-based, halogenated hydrocarbon-based, ketone-based, ketone alcohol-based, ether-based, ester-based solvents, etc. Can be used. More specifically, methanol, ethanol, n-propanol, iso-propanol, n-butanol, benzyl alcohol, methyl cellosolve, ethyl cellosolve, acetone, methyl ethyl ketone, cyclohexanone, methyl acetate, ethyl acetate, n-butyl acetate, Examples include dioxane, tetrahydrofuran, methylene chloride, chloroform, chlorobenzene, toluene and the like. These organic solvents can be used individually by 1 type or in mixture of 2 or more types.

  The charge generation layer 1a is obtained by applying the coating solution for forming the charge generation layer thus obtained by blade coating method, Mayer bar coating method, spray coating method, dip coating method, bead coating method, air knife coating method, curtain coating method, etc. It can form by apply | coating on the electroconductive support body 3, and drying.

  The film thickness of the charge generation layer 1a thus obtained is preferably 0.05 to 5 μm and more preferably 0.1 to 1 μm from the viewpoint of obtaining good electrical characteristics and image quality. When the film thickness of the charge generation layer 1a is less than 0.05 μm, the sensitivity tends to decrease, and when the film thickness exceeds 5 μm, there is a tendency that adverse effects such as defective charging characteristics tend to occur.

  The charge transport layer 2 is a layer containing a charge transport material and a binder resin. The charge transport material used for the charge transport layer 2 can be used without particular limitation as long as it has a function of transporting charges. For example, oxadiazole derivatives such as 2,5-bis (p-diethylaminophenyl) -1,3,4-oxadiazole, 1,3,5-triphenyl-pyrazoline, 1- [pyridyl- (2)] Pyrazoline derivatives such as -3- (p-diethylaminostyryl) -5- (p-diethylaminostyryl) pyrazoline, triphenylamine, tri (P-methyl) phenylamine, N, N′-bis (3,4-dimethylphenyl) ) Aromatic tertiary amino compounds such as biphenyl-4-amine, dibenzylaniline, 9,9-dimethyl-N, N′-di (p-tolyl) fluorenon-2-amine, N, N′-diphenyl- Aromatic tertiary diamino compounds such as N, N′-bis (3-methylphenyl)-[1,1-biphenyl] -4,4′-diamine, 3- (4′dimethyla Nophenyl) -5,6-di- (4′-methoxyphenyl) -1,2,4-triazine, 1,2,4-triazine derivatives, 4-diethylaminobenzaldehyde-1,1-diphenylhydrazone, 4-diphenyl Hydrazone derivatives such as aminobenzaldehyde-1,1-diphenylhydrazone, [p- (diethylamino) phenyl] (1-naphthyl) phenylhydrazone, quinazoline derivatives such as 2-phenyl-4-styryl-quinazoline, 6-hydroxy-2, Benzofuran derivatives such as 3-di (p-methoxyphenyl) -benzofuran, α-stilbene derivatives such as p- (2,2-diphenylvinyl) -N, N′-diphenylaniline, enamine derivatives, N-ethylcarbazole, etc. Carbazole derivatives, poly-N-vinylcarbazole and Hole transport materials such as derivatives thereof, quinone compounds such as chloranil, bromoanil and anthraquinone, tetracyanoquinodimethane compounds, 2,4,7-trinitrofluorenone, 2,4,5,7-tetranitro-9- Fluorenone compounds such as fluorenone, 2- (4-biphenyl) -5- (4-t-butylphenyl) -1,3,4-oxadiazole, 2,5-bis (4-naphthyl) -1,3 Oxadiazole compounds such as 4-oxadiazole, 2,5-bis (4-diethylaminophenyl) 1,3,4 oxadiazole, xanthone compounds, thiophene compounds, 3,3 ′, 5,5′tetra And electron transport materials such as diphenoquinone compounds such as -t-butyldiphenoquinone. Furthermore, as the charge transport material, a polymer having the basic structure of the compound exemplified above in the main chain or the side chain can be used. These charge transport materials can be used singly or in combination of two or more.

  As the binder resin used for the charge transport layer 2, a known resin can be used without any particular limitation, but a resin capable of forming an electrically insulating film is preferably used. For example, polycarbonate resin, polyester resin, methacrylic resin, acrylic resin, polyvinyl chloride resin, polyvinylidene chloride resin, polystyrene resin, polyvinyl acetate resin, styrene-butadiene copolymer, vinylidene chloride-acrylonitrile copolymer, vinyl chloride-acetic acid Vinyl 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, vinylidene chloride polymer wax, polyurea Emissions, and the like. These binder resins can be used singly or in combination of two or more. In particular, a polycarbonate resin, a polyester resin, a methacrylic resin, and an acrylic resin are preferably used because they are excellent in compatibility with the charge transporting material, solubility in a solvent, and strength.

  Further, the blending ratio (mass ratio) of the binder resin and the charge transport material can be arbitrarily set in consideration of a decrease in electrical characteristics and a decrease in film strength.

  In addition, the charge transport layer 2 is added with an antioxidant, a light stabilizer, etc. for the purpose of preventing the photoconductor from being deteriorated by ozone or oxidizing gas generated in the electrophotographic apparatus or light or heat. An agent can be added.

  Here, 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 hindered phenol antioxidants include 2,6-di-t-butyl-4-methylphenol, styrenated phenol, n-octadecyl-3- (3 ′, 5′-di-t-butyl-4 ′. -Hydroxyphenyl) -propionate, 2,2'-methylene-bis- (4-methyl-6-t-butylphenol), 2-t-butyl-6- (3'-t-butyl-5'-methyl-2) '-Hydroxybenzyl) -4-methylphenyl acrylate, 4,4'-butylidene-bis- (3-methyl-6-tert-butylphenol), 4,4'-thio-bis- (3-methyl-6-t -Butylphenol), 1,3,5-tris (4-tert-butyl-3-hydroxy-2,6-dimethylbenzyl) isocyanurate, tetrakis- [methylene-3- (3 ', 5',-di- -Butyl-4'-hydroxyphenyl) propionate] methane, 3,9-bis [2- [3- (3-t-butyl-4-hydroxy-5-methylphenyl) propionyloxy] -1,1-dimethylethyl ] -2,4,8,10-tetraoxaspiro [5,5] undecane and the like.

  Examples of hindered amine antioxidants 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-tetramethylpi-succinate Lysine polycondensate, poly [{6- (1,1,3,3-tetramethylbutyl) imino-1,3,5-triazine-2,4-diimyl} {(2,2,6,6-tetra Methyl-4-piperidyl) imino} hexamethylene {(2,3,6,6-tetramethyl-4-piperidyl) imino}], 2- (3,5-di-t-butyl-4-hydroxybenzyl)- 2-n-butylmalonate bis (1,2,2,6,6-pentamethyl-4-piperidyl), N, N′-bis (3-aminopropyl) ethylenediamine-2,4-bis [N-butyl- N- (1,2,2,6,6-pentamethyl-4-piperidyl) amino] -6-chloro-1,3,5-triazine condensate and the like.

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

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

  These organic sulfur-based antioxidants and organic phosphorus-based antioxidants are referred to as secondary antioxidants, and a synergistic effect can be obtained by using them together with primary antioxidants such as phenols or amines. .

  Examples of the light stabilizer include benzophenone, benzotriazole, dithiocarbamate, and tetramethylpiperidine derivatives.

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

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

  In addition, 2,4-di-t-butylphenyl-3 ', 5'-di-t-butyl-4'-hydroxybenzoate, nickel dibutyl-dithiocarbamate, or the like may be used.

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

  In addition, a solid lubricant or a metal oxide can be dispersed in the charge transport layer 2 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 in the charge transport layer 2, the friction coefficient on the surface of the charge transport layer 2 decreases, so that wear can be suppressed. Further, when the metal oxide is dispersed, the mechanical hardness of the charge transport layer 2 is increased, so that wear can be suppressed. Further, since the fluorine-containing resin particles are hardly dispersed particles, dispersibility is improved when a fluorine-containing polymer-based dispersion aid is used.

  As a method for dispersing the solid lubricant or metal oxide in the charge transport layer 2, a method 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, or a high-pressure treatment type homogenizer is used. be able to. In this dispersion, it is effective to make the dispersed particles 1.0 μm or less, preferably 0.5 μm or less.

  Further, a small amount of silicone oil can be added to the charge transport layer 2 as a leveling agent for improving the smoothness of the coating film.

  The charge transport layer 2 can be formed by applying a coating liquid obtained by mixing / dispersing the above charge transport material, binder resin and other additive materials in a predetermined solvent on the charge generation layer 1a and drying it. it can.

  Examples of the solvent used in the coating liquid for forming the charge transport layer 2 include ordinary organic solvents such as dioxane, tetrahydrofuran, methylene chloride, chloroform, chlorobenzene, and toluene. These may be used alone or in combination of two or more. Can be mixed and used.

  As a method for applying the charge transport layer 2, a normal method such as 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, or a curtain coating method can be used.

  The thickness of the charge transport layer 2 thus obtained is preferably 5 to 50 μm, and more preferably 10 to 40 μm.

  FIG. 1B is a schematic cross-sectional view showing a second embodiment of the electrophotographic photosensitive member of the present invention. The electrophotographic photosensitive member 105 shown in FIG. 1B is similar to the electrophotographic photosensitive member 100 shown in FIG. 1A except that the undercoat layer 4 is provided between the conductive support 3 and the photosensitive layer 6a. It has the same structure.

  The undercoat layer 4 has a function of preventing charge injection from the conductive support 3 to the photosensitive layer 6a when the photosensitive layer 6a is charged. The undercoat layer 4 also functions as an adhesive layer that integrally holds the photosensitive layer 6 a to the conductive support 3. Further, the undercoat layer 4 has a function of preventing light reflection of the conductive support 3. In addition, the undercoat layer 4 may be provided for the purpose of improving electrical characteristics, improving image quality, improving image quality maintenance, improving photosensitive layer adhesion, and improving leakage resistance.

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

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

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

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

  The undercoat layer 4 is formed by applying a coating solution for forming an undercoat layer in which the above materials are mixed / dispersed in a predetermined organic solvent on the conductive support 3 and removing the solvent by drying. Examples of the mixing / dispersing method in preparing the coating solution for forming the undercoat layer 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 resin is dissolved and an electron transporting pigment is mixed / dispersed. Specifically, methanol, ethanol, n-propanol, n-butanol, benzyl alcohol, methyl cellosolve, ethyl cellosolve, acetone, methyl ethyl ketone, cyclohexanone, methyl acetate, n-butyl acetate, dioxane, tetrahydrofuran, methylene chloride, chloroform , Chlorobenzene, toluene and the like, and these can be used alone or in admixture of two or more. The coating solution is dried at a temperature at which the solvent can be evaporated and a film can be formed. The film thickness of the undercoat layer 4 thus obtained is preferably 0.1 to 10 μm, and more preferably 0.5 to 5.0 μm when it does not contain metal oxide fine particles. preferable. Moreover, when containing metal oxide microparticles | fine-particles, it is preferable to exceed 15 micrometers, and it is more preferable that it is 15-50 micrometers. When the thickness of the undercoat layer 4 satisfies the above conditions, local dielectric breakdown (photoreceptor leakage) in the electrophotographic photoreceptor can be more reliably prevented. In addition, stable characteristics can be obtained even in long-term continuous use.

  FIG. 1C is a schematic cross-sectional view showing a third embodiment of the electrophotographic photosensitive member of the present invention. The electrophotographic photoreceptor 110 shown in FIG. 1C has the same configuration as the electrophotographic photoreceptor 105 shown in FIG. 1B except that the intermediate layer 7 is provided on the undercoat layer 4. .

  The material used for the intermediate layer 7 is the same as the material used for the undercoat layer 4, such as a zirconium chelate compound, a zirconium alkoxide compound, and a zirconium coupling agent; a titanium chelate compound, a titanium alkoxide compound, and a titanate. Organic titanium compounds such as coupling agents; aluminum chelate compounds; organoaluminum compounds such as aluminum coupling agents; antimony alkoxide compounds; germanium alkoxide compounds; organic indium compounds such as indium alkoxide compounds and indium chelate compounds; manganese alkoxide compounds and manganese Organic manganese compounds such as chelate compounds; Organotin compounds such as tin alkoxide compounds and tin chelate compounds; Aluminum silicon alloys Kokishido compounds; aluminum titanium alkoxide compound; aluminum zirconium alkoxide compounds include organometallic compounds such as. Among these, organic zirconium compounds, organic titanyl compounds, and organoaluminum compounds are preferably used because of their low residual potential and good electrophotographic characteristics.

  Further, like the undercoat layer 4, the intermediate layer 7 includes vinyltrichlorosilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris-2-methoxyethoxysilane, vinyltriacetoxysilane, γ-glycidoxypropyltri Methoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-chloropropyltrimethoxysilane, γ-2-aminoethylaminopropyltrimethoxysilane, γ-mercapropropyltrimethoxysilane, γ -A silane coupling agent such as ureidopropyltriethoxysilane or β-3,4-epoxycyclohexyltrimethoxysilane can be contained and used. Furthermore, polyvinyl alcohol, polyvinyl methyl ether, poly-N-vinylimidazole, polyethylene oxide, ethyl cellulose, methyl cellulose, ethylene-acrylic acid copolymer, polyamide, polyimide, casein, gelatin, polyethylene, polyester, phenol resin, vinyl chloride- Known binder resins such as a vinyl acetate copolymer, an epoxy resin, polyvinyl pyrrolidone, polyvinyl pyridine, polyurethane, polyglutamic acid, and polyacrylic acid can also be used. These mixing ratios can be appropriately set as necessary.

  Further, in the intermediate layer 7, similarly to the undercoat layer 4, an electron transport pigment can be mixed / dispersed and used. Examples of electron transport pigments include organic pigments such as perylene pigments, bisbenzimidazole perylene pigments, polycyclic quinone pigments, indigo pigments, and quinacridone pigments, and electron-withdrawing pigments such as cyano groups, nitro groups, nitroso groups, and halogen atoms. Examples thereof include organic pigments such as bisazo pigments and phthalocyanine pigments having a substituent, and inorganic pigments such as zinc oxide and titanium oxide. Among these pigments, perylene pigments, bisbenzimidazole perylene pigments and polycyclic quinone pigments are preferably used because of their high electron mobility. If the amount of the electron transporting pigment is too large, the strength of the undercoat layer decreases and a coating film defect is generated. .

  Similar to the undercoat layer 4, the intermediate layer 7 is formed by applying a coating solution obtained by mixing / dispersing the above materials in a predetermined organic solvent onto the substrate 2 and removing the solvent by drying. Examples of the mixing / dispersing method in preparing the coating solution for the undercoat layer include a ball mill, a roll mill, a sand mill, an attritor, and an ultrasonic wave. As the organic solvent, any solvent can be used as long as it does not cause gelation or aggregation when a periodical metal compound or resin is dissolved and an electron transporting pigment is mixed / dispersed. Specifically, methanol, ethanol, n-propanol, n-butanol, benzyl alcohol, methyl cellosolve, ethyl cellosolve, acetone, methyl ethyl ketone, cyclohexanone, methyl acetate, n-butyl acetate, dioxane, tetrahydrofuran, methylene chloride, chloroform , Chlorobenzene, toluene and the like, and these can be used alone or in admixture of two or more. The coating solution is dried at a temperature at which the solvent can be evaporated and a film can be formed. The thickness of the intermediate layer 7 obtained in this way is preferably 0.1 to 10 μm, and more preferably 0.5 to 5 μm. When the film thickness of the intermediate layer 7 satisfies the above conditions, stable characteristics can be obtained even when the electrophotographic photosensitive member is used continuously for a long time.

  FIG. 2A is a schematic cross-sectional view showing a fourth embodiment of the electrophotographic photosensitive member of the present invention. The electrophotographic photoreceptor 115 shown in FIG. 2 (a) has the same configuration as the electrophotographic photoreceptor 100 shown in FIG. 1 (a) except that the protective layer 5 is provided on the photosensitive layer 6a.

  The protective layer 5 is used to prevent chemical change of the charge transport layer 2 when the electrophotographic photosensitive member 115 is charged or to further improve the mechanical strength of the photosensitive layer 6a.

  The protective layer 5 is formed, for example, by applying a coating solution containing a conductive material in an appropriate binder resin on the photosensitive layer 6. The conductive material is not particularly limited, and examples thereof include metallocene compounds such as N, N′-dimethylferrocene, N, N′-diphenyl-N, N′-bis (3-methylphenyl)-[1, Aromatic amine compounds such as 1′-biphenyl] -4,4′-diamine, molybdenum oxide, tungsten oxide, antimony oxide, tin oxide, titanium oxide, indium oxide, tin oxide and antimony, solid solution of barium sulfate and antimony oxide Carrier, mixture of the above metal oxide, titanium oxide, tin oxide, zinc oxide or barium sulfate mixed with the above metal oxide, or titanium oxide, tin oxide, zinc oxide or sulfuric acid For example, a single particle of barium coated with the above metal oxide.

  As the binder resin used for the protective layer 5, polyamide resin, polyvinyl acetal resin, polyurethane resin, polyester resin, epoxy resin, polyketone resin, polycarbonate resin, polyvinyl ketone resin, polystyrene resin, polyacrylamide resin, polyimide resin, polyamideimide Known resins such as resins are used. These can also be used by cross-linking each other as necessary.

Moreover, as the protective layer 5, the cured film formed including the compound represented by following General formula (4) is preferable.
F- [D-SiR ¹¹ _(3-a) (OR ¹² ) _a ] _b (4)
[Wherein, F represents an organic group derived from a photofunctional compound, D represents a divalent group, R ¹¹ represents a hydrogen atom, an alkyl group, or a substituted or unsubstituted aryl group, and R ¹² represents A hydrogen atom, an alkyl group or a trialkylsilyl group, a represents an integer of 1 to 3, and b represents an integer of 1 to 4; ]

—SiR ¹¹ _(3-a) (OR ¹² ) _a in the general formula (4) is a substituted silicon group having a hydrolyzable group, and a three-dimensional Si—O—Si bond (inorganic glass) by a crosslinking reaction. Quality network).

  In the general formula (4), 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 transporting property, and a compound skeleton having an electron transporting property such as a quinone compound, a fluorenone compound, a xanthone compound, a benzophenone compound, a cyanovinyl compound, and an ethylene compound.

［式（５）中、Ａｒ^１〜Ａｒ^４はそれぞれ独立に、置換若しくは未置換のアリール基を示し、Ａｒ^５は、置換若しくは未置換のアリール基、又はアリーレン基を示し、ｋは０又は１を示し、Ａｒ^１〜Ａｒ^４のうちｂ個は、Ｄ−ＳｉＲ^１１ _{（３−ａ）}（ＯＲ^１２）_ａで表される基に結合する結合手を有する。］ Preferable examples of the organic group represented by F include a group represented by the following general formula (5). When F is a group represented by the following general formula (5), particularly excellent photoelectric characteristics and mechanical characteristics are exhibited.

[In Formula (5), 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, and k is 0 or 1 B of Ar ^{1 to} Ar ⁴ have a bond bonded to a group represented by D-SiR ¹¹ _(3-a) (OR ¹² ) _a . ]

Ar ^{1 to} Ar ⁴ in the general formula (5) are preferably any of the following formulas (5-1) to (5-7).

−Ａｒ−Ｚ_ｓ−Ａｒ−Ｘ_ｍ （５−７）
［式中、Ｒ^２１は水素原子、炭素数１〜４のアルキル基、炭素数１〜４のアルキル基若しくは炭素数１〜４のアルコキシ基で置換されたフェニル基、未置換のフェニル基、又は炭素数７〜１０のアラルキル基を示し、Ｒ^２２〜Ｒ^２４はそれぞれ独立に、水素原子、炭素数１〜４のアルキル基、炭素数１〜４のアルコキシ基、炭素数１〜４のアルコキシ基で置換されたフェニル基、未置換のフェニル基、炭素数７〜１０のアラルキル基、又はハロゲン原子を示し、Ａｒは置換又は未置換のアリーレン基を示し、ＸはＤ−ＳｉＲ^１１ _{（３−ａ）}（ＯＲ^１２）_ａを示し、ｍ及びｓはそれぞれ独立に、０又は１を示し、ｔは１〜３の整数を示す。］

_{-Ar-Z s -Ar-X m} (5-7)
[Wherein, R ²¹ 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, R 22 ^{to R 24} each independently represent a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms Represents a phenyl group, an unsubstituted phenyl group, an aralkyl group having 7 to 10 carbon atoms, or a halogen atom, Ar represents a substituted or unsubstituted arylene group, and X represents D-SiR ¹¹ _{(3-a )} (OR ¹² ) _a represents, m and s each independently represent 0 or 1, and t represents an integer of 1 to 3. ]

  Here, as Ar in Formula (5-7), what is represented by following formula (5-8) or (5-9) is preferable.

［式中、Ｒ^２５及びＲ^２６はそれぞれ独立に、水素原子、炭素数１〜４のアルキル基、炭素数１〜４のアルコキシ基、炭素数１〜４のアルコキシ基で置換されたフェニル基、未置換のフェニル基、炭素数７〜１０のアラルキル基、又はハロゲン原子を示し、ｔは１〜３の整数を示す。］

[Wherein, R ²⁵ and R ²⁶ are each independently a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, a phenyl group substituted with an alkoxy group having 1 to 4 carbon atoms, An unsubstituted phenyl group, a C7-10 aralkyl group, or a halogen atom is shown, t shows the integer of 1-3. ]

  Moreover, as Z in Formula (5-7), what is represented by either of following formula (5-10)-(5-17) is preferable.

_{- (CH 2) q - (} 5-10)
_{- (CH 2 CH 2 O)} r - (5-11)

［式中、Ｒ^２７及びＲ^２８はそれぞれ独立に、水素原子、炭素数１〜４のアルキル基、炭素数１〜４のアルコキシ基、炭素数１〜４のアルコキシ基で置換されたフェニル基、未置換のフェニル基、炭素数７〜１０のアラルキル基、又はハロゲン原子を示し、Ｗは２価の基を表し、ｑ及びｒはそれぞれ独立に、１〜１０の整数を表し、ｔは１〜３の整数を表す。］

[Wherein, R ²⁷ and R ²⁸ are each independently a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, 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 represents an integer of 1 to 10; An integer of 3 is represented. ]

  W in the general formulas (5-16) to (5-17) is any one of divalent groups represented by the following general formulas (5-18) to (5-26). Is preferred.

—CH ₂ — (5-18)
_{-C (CH 3) 2 - (} 5-19)
-O- (5-20)
-S- (5-21)
_{-C (CF 3) 2 - (} 5-22)
—Si (CH ₃ ) ₂ — (5-23)

［式中、ｕは０〜３の整数を示す。］

[Wherein u represents an integer of 0 to 3. ]

In the general formula (5), Ar ⁵ is an aryl group exemplified in the description of Ar ^{1 to} Ar ⁴ when k is 0, and when k is 1, a predetermined hydrogen atom is formed from the aryl group. An arylene group excluding

In the general formula (4), the divalent group represented by D is directly bonded to F that imparts photoelectric characteristics and a three-dimensional inorganic glassy network -SiR ¹¹ _(3-a) (OR ¹² ). _The inorganic glassy network has a function of binding a to the inorganic glassy network, which is hard and brittle, and has a function of improving the toughness of the film.

Examples of the divalent group represented by D, and _{specifically, -C p H 2p -, -} C p H 2p-2 -, - C p H2 p-4 - 2 divalent hydrocarbon group represented by (p 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 the general formula (4), b is preferably 2 or more. When b is 2 or more, the photofunctional organosilicon compound represented by the general formula (4) has two or more Si atoms, which facilitates formation of an inorganic glassy network, and mechanical strength increases. It tends to improve.

  In addition, the compound represented by the said General formula (4) may be used individually by 1 type, and may be used together 2 or more types.

A compound represented by the following general formula (6) may be used in combination with the compound represented by the general formula (4) for the purpose of further improving the mechanical strength of the cured film.
B (—SiR ¹¹ _(3-a) (OR ¹² ) _a ) _g (6)
^Wherein, R ^{11, R 12,} a represents an ^{R 11, R 12,} a same definition and the general formula (4), B is, may include a branched hydrocarbon group having g valences, g A g-valent group composed of a valent phenyl group, -NH-, or a combination of two or more thereof, and g represents an integer of 2 or more. ]

The compound represented by the general formula (6) is a compound having a substituted silicon group having a hydrolyzable group represented by -SiR ¹¹ _(3-a) (OR ¹² ) _a . The compound represented by the general formula (6) is bonded to the Si—O—Si bond by the reaction with the compound represented by the general formula (4) or the reaction between the compounds represented by the general formula (4). To give a three-dimensional crosslinked cured film. When the compound represented by the general formula (6) and the compound represented by the general formula (4) are used in combination, the crosslinked structure of the cured film is likely to be three-dimensional, and the flexibility is appropriate for the cured film. Therefore, stronger mechanical strength can be obtained.

  Preferred examples of the compound represented by the general formula (6) are shown in Table 1. In Table 1, Me represents a methyl group, Et represents an ethyl group, and Pr represents a propyl group.

  In addition to the compound represented by the general formula (4), another compound capable of crosslinking reaction may be used in combination. As such a compound, various silane coupling agents, commercially available silicone hard coat agents, and the like can be used.

  Examples of the silane coupling agent include vinyltrichlorosilane, vinyltrimethoxysilane, vinyltriethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, γ-glycidoxypropyltrimethoxysilane, and γ-glycidoxypropyl. Trimethoxysilane, γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, γ-aminopropylmethyldimethoxysilane, N-β (aminoethyl) γ-aminopropyltriethoxysilane, tetramethoxysilane, methyltrimethoxy Examples thereof include silane and dimethyldimethoxysilane.

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

  In addition, a fluorine-containing compound can be added to the protective layer 5 for the purpose of imparting surface lubricity. By improving the surface lubricity, the coefficient of friction with the cleaning member decreases, and the wear resistance can be improved. It also has the effect of preventing the adhesion of discharge products, developer, paper dust, etc. to the surface of the photoreceptor, which helps to improve the life of the photoreceptor.

  As the fluorine-containing compound, a fluorine atom-containing polymer such as polytetrafluoroethylene can be added as it is, or fine particles of these polymers can be added. In the case of a cured film formed of the compound represented by the general formula (4), it is desirable to add a fluorine-containing compound capable of reacting with alkoxysilane to constitute a part of the crosslinked film. Examples of such fluorine-containing compounds include (tridecafluoro-1,1,2,2-tetrahydrooctyl) triethoxysilane, (3,3,3-trifluoropropyl) trimethoxysilane, 3- (heptafluoro Isopropoxy) propyltriethoxysilane, 1H, 1H, 2H, 2H-perfluoroalkyltriethoxysilane, 1H, 1H, 2H, 2H-perfluorodecyltriethoxysilane, 1H, 1H, 2H, 2H-perfluorooctyltri An ethoxysilane etc. are mentioned.

  The content of the fluorine-containing compound is preferably 20% by mass or less based on the total amount of the protective layer 5. 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 protective layer 5 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. As content of antioxidant, 15 mass% or less is preferable on the basis of the protective layer 5 whole quantity, and 10 mass% or less is still more preferable.

  Here, as the hindered phenol antioxidant, 2,6-di-t-butyl-4-methylphenol, 2,5-di-t-butylhydroquinone, N, N′-hexamethylenebis (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-5-methylbenzyl) -4-methylphenyl acrylate, 4,4'-butylidene bis (3-methyl -6-t-butylphenol) and the like.

  Moreover, it is also possible to add the additive used for well-known coating-film formation to the protective layer 5, and add well-known additives, such as a leveling agent, a ultraviolet absorber, a light stabilizer, and surfactant. be able to.

  The protective layer 5 can be formed by applying a coating solution containing the above compound onto the charge transport layer 6 and subjecting it to a heat treatment. Thereby, the compound etc. which are represented with the said General formula (4) 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 such as the photosensitive layer 6a on which the protective layer 5 is formed, 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.

  As a coating method of the coating liquid for forming the protective layer 5, conventional methods such as 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 are used. Can be used.

  Moreover, as a solvent used for the coating liquid for forming the protective layer 5, dioxane, tetrahydrofuran, methylene chloride, chloroform, chlorobenzene, toluene, water, methanol, ethanol, n-propanol, i-propanol, n-butanol, Usual organic solvents such as benzyl alcohol, methyl cellosolve, ethyl cellosolve, acetone, methyl ethyl ketone, cyclohexanone, methyl acetate, n-butyl acetate, dimethyl ether and dibutyl ether can be used. These may be used alone or in combination of two or more, but it is preferable to use a solvent that hardly dissolves the photosensitive layer 6a to which the coating solution is applied.

  The thickness of the protective layer 5 having the above-described configuration is preferably 0.5 to 20 μm, more preferably 1 to 20 μm, and still more preferably 2 to 10 μm.

  The electrophotographic photosensitive member of the present invention is not limited to the above-described embodiment. For example, an electrophotographic photosensitive member 120 (fifth embodiment of the electrophotographic photosensitive member of the present invention) shown in FIG. The undercoat layer 4 may be provided between the conductive support 3 and the photosensitive layer 6a, and the protective layer 5 may be further provided on the photosensitive layer 6a.

  In the electrophotographic photoreceptors 100, 105, 110, 115, and 120 of the above-described embodiment, the case where the photosensitive layer 6a has a laminated structure has been described. For example, the electron shown in FIG. Photosensitive member 125 (As in the sixth embodiment of the electrophotographic photosensitive member of the present invention, the photosensitive layer 6a may have a single layer structure. In this case as well, the conductive support 3 and The undercoat layer 4 and the intermediate layer 7 may be provided between the photosensitive layer 6a and the protective layer 5 may be provided on the photosensitive layer 6a.

  Next, another embodiment of the electrophotographic photosensitive member of the present invention will be further described.

  FIG. 3A is a schematic cross-sectional view showing a seventh embodiment of the electrophotographic photosensitive member of the present invention. The electrophotographic photoreceptor 130 shown in FIG. 3A is a laminated type in which functions are separated into a layer containing a charge generation material (charge generation layer 1b) and a layer containing a charge transport material (charge transport layer 2). The photosensitive layer 6b is provided and has a structure in which a charge generation layer 1b and a charge transport layer 2 are sequentially laminated on a conductive support 3. The charge generation layer 1b contains a composite of a hydroxygallium phthalocyanine pigment and a hydroxyketone compound.

  First, a composite of a hydroxygallium phthalocyanine pigment and a hydroxyketone compound contained in the charge generation layer 1b of the electrophotographic photoreceptor 130 of this embodiment will be described.

  The composite contained in the charge generation layer 1b of the electrophotographic photoreceptor 130 of the present embodiment is a composite of the present invention formed by combining a hydroxygallium phthalocyanine pigment and a hydroxyketone compound.

  A method for obtaining this complex will be described below with reference to preferred embodiments of the method for producing the complex of the present invention.

  In the X-ray diffraction spectrum using CuKα characteristic X-rays, the manufacturing method of the composite in the present embodiment is 6.9 °, 13.2 to 14.2 °, 16.2 °, 16.2 °, 16. Type I hydroxygallium phthalocyanine pigments having diffraction peaks at 5 °, 26.0 ° and 26.4 °, or 7.0 °, 13.4 °, 16.6 °, 26.0 ° and 26.7 ° And a wet pulverization step of wet pulverizing a mixture containing a hydroxyketone compound and a predetermined solvent. Through this wet pulverization treatment step, the crystal conversion and refinement of the hydroxygallium phthalocyanine pigment and the composite of the hydroxygallium phthalocyanine pigment and the hydroxyketone compound are performed. After the wet pulverization treatment step, the mixture is filtered, washed with an appropriate solvent, and dried to obtain a composite.

  The type I hydroxygallium phthalocyanine pigment used in the method for producing a composite according to this embodiment can be obtained by acid pasting treatment of the above-mentioned crude gallium phthalocyanine.

  As the hydroxyketone compound, those similar to the hydroxyketone compound contained in the charge generation layer 1a of the electrophotographic photoreceptor 100 according to the first embodiment of the present invention described above can be used.

  Examples of the solvent contained in the above mixture 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; Examples include ketones such as acetone, methyl ethyl ketone, and methyl iso-butyl ketone, and dimethyl sulfoxide.

  As a method of wet pulverizing the above mixture, for example, it can be performed by a pulverizer using a spherical medium having an outer diameter of 0.1 to 3.0 mm, and a spherical medium having an outer diameter of 0.2 to 2.5 mm. It is more preferable to carry out using. When the outer diameter of the media is larger than 3.0 mm, the pulverization efficiency is lowered, so that the particle diameter is not reduced and aggregates tend to be easily generated. Moreover, when the outer diameter of the medium is smaller than 0.1 mm, it tends to be difficult to separate the medium and the composite. In addition, when the media is not spherical, but in other shapes such as a columnar shape or an indefinite shape, the grinding efficiency is reduced, and the media is easily worn by grinding, and the wear powder becomes an impurity and easily deteriorates the properties of the composite. Tend to be.

  The material of the media is not particularly limited, but those that do not easily cause image quality defects even when mixed in the composite are preferable, and glass, zirconia, alumina, menor and the like are preferable.

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

  Although the usage-amount of the said media changes also with apparatuses to be used, it is preferable that it is 50 mass parts or more with respect to 1 mass part of hydroxygallium phthalocyanine pigments, and it is more preferable that it is 55-100 mass parts. 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.

  Regarding the content ratio of the I-type hydroxygallium phthalocyanine pigment and the hydroxyketone compound in the above mixture, the content ratio of the hydroxyketone compound is 0.01 to 20 parts by mass with respect to 100 parts by mass of the hydroxygallium phthalocyanine pigment. Preferably, it is 0.1-15 mass parts, It is especially preferable that it is 0.2-10 mass parts. When the content ratio of the hydroxyketone compound is less than 0.01 parts by mass, the effect of suppressing the occurrence of image quality defects such as fogging tends to be insufficient. On the other hand, when the content ratio of the hydroxyketone compound exceeds 20 parts by mass, the hydroxyketone compound is not sufficiently dissolved in the coating solution for forming the charge generation layer 1b to form the charge generation layer 1b, and the uniform charge generation layer 1b. Tends to be difficult to form. In addition, said content rate is a thing in the mixture before wet-grinding, ie, preparation ratio, and does not necessarily show the content rate of the hydroxygallium phthalocyanine pigment and hydroxyketone compound in the composite finally obtained. . Therefore, when a portion of the hydroxyketone compound is removed together with the solvent when washing the mixture that has undergone the wet pulverization step, the charging ratio of the hydroxygallium phthalocyanine pigment and the hydroxyketone compound and the hydroxy content contained in the resulting composite are determined. The ratio of the gallium phthalocyanine pigment and the hydroxyketone compound may not match.

  Moreover, it is preferable that the content rate of the solvent contained in a mixture is 5-50 mass parts with respect to 1 mass part of I type hydroxygallium phthalocyanine pigments, and it is more preferable that it is 10-30 mass parts. If the solvent content is less than 5 parts by mass, the viscosity during wet pulverization will increase and the impact energy of the media will decrease, so the dispersion will tend to be insufficient, and if it exceeds 50 parts by mass, The viscosity is too low and the dispersion efficiency tends to decrease.

  The temperature at which the wet pulverization is performed is preferably 0 to 100 ° C, more preferably 5 to 80 ° C, and still more preferably 10 to 50 ° C. When the temperature during wet pulverization is lower than 0 ° C., the rate of crystal transition tends to be slow, and when this temperature exceeds 100 ° C., the solubility of the hydroxygallium phthalocyanine pigment increases, Since it becomes easy to grow, atomization tends to be difficult.

  The time for performing the wet pulverization is preferably 10 to 400 hours, for example, when the glass spherical media having an outer diameter of 0.1 to 3.0 mm is used as the medium at 25 ° C., and is 20 to 300 hours. It is more preferable, and it is still more preferable that it is 30 to 200 hours.

In the method for producing a composite according to this embodiment, the time for performing wet pulverization is set so that the volume average particle size of the composite is 0.20 μm or less and the BET specific surface area is 45 m ² / g or more. It is preferable. Here, the volume average particle diameter of the composite can be determined by a laser scattering diffraction type particle size distribution analyzer (LA-700, manufactured by Horiba, Ltd.).

  In addition, as a condition of the wet grinding, the type I hydroxygallium phthalocyanine pigment has a Bragg angle (2θ ± 0.2 °) of 7.5 ° and 28.3 ° in an X-ray diffraction spectrum using CuKα characteristic X-rays. Crystal transformation to a hydroxygallium phthalocyanine pigment having diffraction peaks, preferably at 7.5 °, 9.9 °, 12.5 °, 16.3 °, 18.6 °, 25.1 ° and 28.3 ° It is preferable to set the conditions.

  Examples of the solvent for washing the mixture after the wet pulverization step include acetone, methyl ethyl ketone, methanol, ethanol, water, xylene, toluene, n-butyl acetate, and n-ethyl acetate.

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

  Next, each component of the electrophotographic photoreceptor 130 will be described.

  The conductive support 3 and the charge transport layer 2 can be the same as the conductive support 3 and the charge transport layer 2 of the electrophotographic photosensitive member 100 of the first embodiment of the present invention described above, respectively. .

  The charge generation layer 1b contains a composite of a hydroxygallium phthalocyanine pigment and a hydroxyketone compound obtained by the above-described composite manufacturing method, and a binder resin.

  As binder resin, polycarbonate, polystyrene, polysulfone, polyester, polyimide, polyester carbonate, polyvinyl butyral, methacrylate ester polymer, vinyl acetate homopolymer or copolymer, cellulose ester, cellulose ether, polybutadiene, polyurethane, phenoxy resin , Epoxy resins, silicone resins, fluororesins, and partially cross-linked cured products thereof. One of these can be used alone, or two or more can be used in combination.

  The compounding ratio (mass ratio) of the composite and the binder resin in the charge generation layer 1b is preferably 10: 1 to 1:10, more preferably 8: 2 to 3:10. If the amount of the composite exceeds 10 times the amount of the binder resin, the dispersibility of the composite in the dispersion used in the production process of the electrophotographic photoreceptor tends to be insufficient. When the blending amount of the binder resin is less than 1/10, the sensitivity of the electrophotographic photosensitive member tends to be insufficient.

  Furthermore, the charge generation layer 1b may contain a charge generation material other than the above-described composite. Here, examples of other charge generation materials contained in the charge generation layer 1b include azo pigments, perylene pigments, and condensed aromatic pigments. In the present embodiment, it is preferable to contain a metal-containing or metal-free phthalocyanine, and in particular, a hydroxygallium phthalocyanine pigment other than the above-mentioned hydroxygallium phthalocyanine pigment, a chlorogallium phthalocyanine pigment, a dichlorotin phthalocyanine pigment, or an oxytitanyl phthalocyanine pigment. It is preferable to contain. Further, the content ratio of these other charge generation materials is preferably 50% by mass or less based on the total amount of solids contained in the charge generation layer 1b.

  When another layer such as the charge transport layer 2 is further formed on the charge generation layer 1b, the charge generation layer 1b is not dissolved or swollen by the solvent used in the coating solution. The combination of the binder resin of the charge generation layer 1b and the solvent of the coating liquid applied on the charge generation layer 1b is preferably selected as appropriate. Moreover, it is preferable to use the binder resin of the charge generation layer 1b and the binder resin of the charge transport layer 2 in combination with each other whose refractive indices are close to each other. Is preferably 1 or less. When a binder resin having a similar refractive index is used in combination, light reflection at the interface between the charge generation layer 1b and the charge transport layer 2 is suppressed, and the interference fringe prevention effect tends to be improved.

  The charge generation layer 1b is made by adding a composite and a binder resin to a predetermined solvent, a sand mill, a colloid mill, an attritor, a dyno mill, a jet mill, a coball mill, a roll mill, an ultrasonic disperser, a gorin homogenizer, a microfluidizer, and an optimizer. The coating liquid obtained by mixing and dispersing using a milder, etc. is applied by blade coating method, Meyer bar coating method, spray coating method, dip coating method, bead coating method, air knife coating method, curtain coating method, etc. It can be formed by applying and drying.

  Specific examples of the solvent used in the coating solution for the charge generation layer 1b include methanol, ethanol, n-butanol, benzyl alcohol, acetone, methyl ethyl ketone, cyclohexanone, methyl acetate, n-butyl acetate, dioxane, tetrahydrofuran, and methylene chloride. , Chloroform, toluene, xylene, chlorobenzene, dimethylformamide, dimethylacetamide, water and the like, and these may be used alone or as a mixture of two or more.

  The film thickness of the charge generation layer 1b thus obtained is preferably 0.05 to 5 μm and more preferably 0.1 to 1 μm from the viewpoint of obtaining good electrical characteristics and image quality. When the film thickness of the charge generation layer 1b is less than 0.05 μm, the sensitivity tends to decrease, and when the film thickness exceeds 5 μm, there is a tendency that adverse effects such as defective charging characteristics tend to occur.

  FIG. 3B is a schematic cross-sectional view showing an eighth embodiment of the electrophotographic photosensitive member of the present invention. The electrophotographic photosensitive member 135 shown in FIG. 3B is similar to the electrophotographic photosensitive member 130 shown in FIG. 3A except that the undercoat layer 4 is provided between the conductive support 3 and the photosensitive layer 6b. It has the same structure.

  The undercoat layer 4 has a function of preventing charge injection from the conductive support 3 to the photosensitive layer 6b when the photosensitive layer 6b is charged. The undercoat layer 4 also functions as an adhesive layer that integrally holds the photosensitive layer 6b to the conductive support 3. Further, the undercoat layer 4 has a function of preventing light reflection of the conductive support 3.

  The undercoat layer 4 can be the same as the undercoat layer 4 of the electrophotographic photosensitive member 105 of the second embodiment of the present invention described above.

  FIG. 3C is a schematic cross-sectional view showing a ninth embodiment of the electrophotographic photosensitive member of the present invention. The electrophotographic photoreceptor 140 shown in FIG. 3C has the same configuration as the electrophotographic photoreceptor 135 shown in FIG. 3B except that the intermediate layer 7 is provided on the undercoat layer 4. .

  The intermediate layer 7 can be the same as the intermediate layer 7 of the electrophotographic photoreceptor 110 of the third embodiment of the present invention described above.

  FIG. 4A is a schematic cross-sectional view showing a tenth embodiment of the electrophotographic photosensitive member of the present invention. The electrophotographic photosensitive member 145 shown in FIG. 4A has the same configuration as the electrophotographic photosensitive member 130 shown in FIG. 3A except that the protective layer 5 is provided on the photosensitive layer 6b.

  The protective layer 5 is provided to prevent chemical change of the charge transport layer 2 when the electrophotographic photosensitive member 145 is charged or to further improve the mechanical strength of the photosensitive layer 6b. The protective layer 5 is formed by applying a coating solution containing a conductive material in an appropriate binder resin on the photosensitive layer 6b.

  The protective layer 5 can be the same as the protective layer 5 of the electrophotographic photosensitive member 115 of the fourth embodiment of the present invention described above.

  In addition, the electrophotographic photosensitive member of the present invention including the charge generation layer containing the composite of the present invention is not limited to the above-described embodiment. For example, the electrophotographic photosensitive member 150 (see FIG. 4B) As in the eleventh embodiment of the electrophotographic photosensitive member of the present invention, an undercoat layer 4 is provided between the conductive support 3 and the photosensitive layer 6b, and a protective layer 5 is further provided on the photosensitive layer 6b. It may be.

  In the electrophotographic photoreceptors 130, 135, 140, 145, and 150 of the above-described embodiment, the case where the photosensitive layer 6b has a laminated structure has been described. For example, the electron shown in FIG. Photosensitive member 155 (As in the twelfth embodiment of the electrophotographic photosensitive member of the present invention, the photosensitive layer 6b may have a single layer structure. In this case as well, the conductive support 3 may be used. The undercoat layer 4 and the intermediate layer 7 may be provided between the photosensitive layer 6b and the protective layer 5 may be provided on the photosensitive layer 6a.

(Electrophotographic apparatus and process cartridge)
Next, the electrophotographic apparatus and the process cartridge of the present invention will be described.

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

  Here, the electrophotographic photoreceptor 207 includes, in the photosensitive layer, hydroxygallium phthalocyanine having a maximum peak wavelength in the range of 810 to 839 nm in the spectral absorption spectrum in the wavelength range of 600 to 900 nm, and the above general formula (1). Containing the hydroxyketone compound represented. The configuration of the electrophotographic photoreceptor 207 is not particularly limited as long as it includes a photosensitive layer containing the hydroxygallium phthalocyanine and the hydroxyketone compound. For example, the electrophotographic photoreceptor 207 shown in FIGS. Either may be sufficient.

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

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

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

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

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

  When the photosensitive member is charged using these conductive members, a voltage is applied to the conductive member. The applied voltage may be a DC voltage or a DC voltage superimposed with an AC voltage.

  The shape of the contact-type charging member may be any shape such as a roller, a blade, or a belt, and can be arbitrarily selected according to the specifications and form of the electrophotographic apparatus.

  There is no particular limitation on the charging method used in the electrophotographic photosensitive member of the present invention. However, in recent years, a contact charging method that generates less ozone and has a low environmental load tends to be used preferably. In general, the contact charging method has a weaker charging ability than non-contact charging methods such as scorotron and corotron, and is likely to be a problem particularly in an electrophotographic apparatus that requires a high-speed response. When the charging capability is weak, the charge remaining in the photosensitive layer of the electrophotographic photosensitive member causes image quality defects such as fogging. However, according to the electrophotographic photosensitive member of the present invention, since there are few hydroxygallium phthalocyanine pigment particles having a broken crystal type that cause charge to remain in the charge generation layer, the above-described image quality defects occur. It is difficult and can be suitably used in combination with a contact charging system.

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

  As 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 toner used for the developing device 211 includes, for example, a binder resin and a colorant. Examples of the binder resin include homopolymers and copolymers such as styrenes, monoolefins, vinyl esters, α-methylene aliphatic monocarboxylic acid esters, vinyl ethers, and vinyl ketones. Typical binder resins include polystyrene, styrene-alkyl acrylate copolymer, styrene-alkyl methacrylate copolymer, styrene-acrylonitrile copolymer, styrene-butadiene copolymer, styrene-maleic anhydride copolymer. Examples thereof include coalescence, polyethylene, and polypropylene. Furthermore, polyester, polyurethane, epoxy resin, silicone resin, polyamide, modified rosin, paraffin wax, and the like can also be mentioned.

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

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

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

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

  As other inorganic fine particles, small-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. Inorganic or organic fine particles may be used in combination. As these other inorganic fine particles, known ones can be used.

  In addition, the small-diameter inorganic fine particles are effective because surface dispersibility increases dispersibility and increases the powder flowability.

  As a method for producing the toner used in the present invention, a polymerization method such as an emulsion polymerization aggregation method or a dissolution suspension method is preferably used because high shape controllability can be obtained. In addition, a manufacturing method may be performed in which the toner obtained by the above method is used as a core, and agglomerated particles are further adhered and heat-fused to give a core-shell structure. When an external additive is added, it can be produced by mixing the toner and the external additive with a Henschel mixer or a V blender. Further, when the toner is manufactured by a wet method, it can be externally added by a wet method.

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

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

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

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

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

  As described above, the electrophotographic apparatus 230 is different in that the intermediate transfer method is applied. However, as in the case of the electrophotographic apparatus 200 shown in FIG. 5, the specific hydroxygallium phthalocyanine and the general formula ( By using the electrophotographic photoreceptor 207 in which the hydroxyketone compound represented by 1) is contained in the photosensitive layer, it is possible to stably obtain a good image quality free from image quality defects such as fog and ghost over a long period of time. it can.

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

  FIG. 7 is a sectional view schematically showing the basic configuration of another preferred embodiment of the electrophotographic apparatus of the present invention. An electrophotographic apparatus 220 shown in FIG. 7 is an intermediate transfer type electrophotographic 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 electrophotographic apparatus 220 are hydroxygallium phthalocyanine having the maximum peak wavelength in the range of 810 to 839 nm in the spectral absorption spectrum in the wavelength range of 600 to 900 nm, respectively An electrophotographic photosensitive member comprising a photosensitive layer containing a hydroxyketone compound represented by the general formula (1).

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

  Further, a laser light source (exposure device) 403 is disposed at a predetermined position in the housing 400, and the surface of the electrophotographic photoreceptors 401a to 401d after charging is irradiated with laser light emitted from the laser light source 403. Is possible. Accordingly, charging, exposure, development, primary transfer, and cleaning are sequentially performed in the rotation process of the electrophotographic photosensitive members 401a to 401d, and the toner images of the respective colors are transferred onto the intermediate transfer belt 409 in an overlapping manner. Here, by using the electrophotographic photosensitive members 401a to 401d including the photosensitive layer containing the specific hydroxygallium phthalocyanine and the hydroxyketone compound, even in a tandem color electrophotographic apparatus, high image quality and environmental protection can be achieved. It becomes possible to achieve a reduction in load at a high level.

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

  A tray (transfer medium tray) 411 is provided at a predetermined position in the housing 400, and the transfer medium 500 such as paper in the tray 411 is transferred to the intermediate transfer belt 409 and the secondary transfer roll by the transfer roll 412. Then, the paper is sequentially transferred between the two fixing rolls 414 that are in contact with each other and the two fixing rolls 414, 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. There may be. Conventionally known resins can be used as the resin material used as the base material of the intermediate transfer member in the belt shape. For example, polyimide resin, polycarbonate resin (PC), polyvinylidene fluoride (PVDF), polyalkylene terephthalate (PAT), ethylenetetrafluoroethylene copolymer (ETFE) / PC, ETFE / PAT, PC / PAT blend material, polyester Resin materials such as polyether ether ketone and polyamide, and resin materials using these as main raw materials. Furthermore, a resin material and an elastic material can be blended and used.

  As an elastic material, polyurethane, chlorinated polyisoprene, NBR, chloropyrene rubber, EPDM, hydrogenated polybutadiene, butyl rubber, silicone rubber, or the like can be used, or a material obtained by blending two or more kinds can be used. If necessary, a conductive agent imparting electronic conductivity or a conductive agent having ionic conductivity is added to the resin material and elastic material used for these base materials in combination of one kind or two or more kinds. Among these, it is preferable to use a polyimide resin in which a conductive agent is dispersed from the viewpoint of excellent mechanical strength. As the conductive agent, a conductive polymer such as carbon black, metal oxide, or polyaniline can be used.

  When a belt-shaped configuration such as the intermediate transfer belt 409 is employed as the intermediate transfer member, the thickness of the belt is generally preferably 50 to 500 μm and more preferably 60 to 150 μm, but is appropriately selected according to the hardness of the material. be able to.

  For example, a belt made of a polyimide resin in which a conductive agent is dispersed is 5 to 20% by mass as a conductive agent in a polyamic acid solution, which is a polyimide precursor, as described in JP-A-63-311263. After the carbon black is dispersed, the dispersion is cast on a metal drum and dried, and then the film peeled off from the drum is stretched at a high temperature to form a polyimide film. Can be produced.

  The film molding is generally performed by injecting a polyamic acid solution film-forming stock solution in which a conductive agent is dispersed into a cylindrical mold and, for example, heating at 100 to 200 ° C. at a rotational speed of 500 to 2000 rpm. The film was formed into a film by a centrifugal molding method while 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. The intermediate transfer member may have a surface layer.

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

  FIG. 8 is a sectional view schematically showing a preferred embodiment of the process cartridge of the present invention. In addition to the electrophotographic photosensitive member 207, the process cartridge 300 is provided with a charging device 208, a developing device 211, a cleaning device (cleaning means) 213, an opening 218 for exposure, and an opening 217 for static elimination exposure. Are combined and integrated with each other. The electrophotographic photoreceptor 207 contains hydroxygallium phthalocyanine having a maximum peak wavelength in the range of 810 to 839 nm in the spectral absorption spectrum in the wavelength range of 600 to 900 nm and the hydroxyketone compound represented by the above general formula (1). A photosensitive layer is provided.

  The process cartridge 300 is detachable from an electrophotographic apparatus main body including a transfer device 212, a fixing device 215, and other components not shown, and the electrophotographic apparatus together with the electrophotographic apparatus main body. It constitutes.

  Since the electrophotographic apparatus and the process cartridge of the present invention described above are provided with the electrophotographic photosensitive member of the present invention, they have sufficient sensitivity and sufficiently suppress the occurrence of image quality defects due to fogging and ghosting. Stable image quality can be obtained over a period of time.

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

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

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

  The BET specific surface area value of the hydroxygallium phthalocyanine pigment was measured by a nitrogen substitution method using a BET specific surface area measuring device (Flow Soap II 2300, manufactured by Shimadzu Corporation).

Example 1
60 parts by mass of zinc oxide (Takeca prototype, specific surface area value 16 m ² / g, average particle size 70 nm) surface-treated with a silane coupling agent (KBM603, manufactured by Shin-Etsu Chemical Co., Ltd.) and a block as a curing agent 15 parts by mass of isocyanate (Sumijour 3175, manufactured by Sumitomo Bayern Urethane Co., Ltd.) and 6 parts by mass of butyral resin (BM-1, manufactured by Sekisui Chemical Co., Ltd.) were dissolved in 60 parts by mass of methyl ethyl ketone. This solution was dispersed in a sand mill for 2 hours using 1 mmφ glass beads to obtain a dispersion. As a catalyst, 0.005 part by mass of dioctyltin dilaurate was added to the resulting dispersion to obtain a coating liquid for forming an undercoat layer. The obtained coating solution is applied on an aluminum substrate having a diameter of 30 mm, a length of 251 mm, and a thickness of 1 mm by a dip coating method, followed by drying and curing at 160 ° C. for 100 minutes to form an undercoat layer having a thickness of 20 μm. did.

  Next, 1 part by mass of type I hydroxygallium phthalocyanine was wet-pulverized by stirring for 68 hours at 25 ° C. using a glass stirring tank having a stirring device together with 15 parts by weight of N, N-dimethylformamide. The obtained crystals were washed with acetone, dried, and the X-ray diffraction spectrum using CuKα characteristic X-rays showed Bragg angles (2θ ± 0.2 °) of 7.5 ° and 28.3 °. Thus, 0.9 part by mass of a hydroxygallium phthalocyanine pigment having a diffraction peak was obtained.

When the spectral absorption spectrum of the obtained hydroxygallium phthalocyanine pigment was measured, the maximum peak wavelength (λ _max ) in the range of 600 to 900 nm was present at 824 nm. Further, when this hydroxygallium phthalocyanine pigment was observed using a transmission electron micrograph, it was confirmed that the number of particles having a particle size of 0.3 μm or more per 30 μm ² was 1 or less on the observation image. Moreover, it was 68.3 m < ² > / g when the BET specific surface area value was measured.

  20 parts by mass of this hydroxygallium phthalocyanine pigment, 0.5 parts by mass of 1- (2-cyclohexanonyl) cyclohexanol represented by the above formula (3-1), vinyl chloride-vinyl acetate copolymer resin as a binder resin (VMCH, manufactured by Nihon Unicar Co., Ltd.) A mixture of 16 parts by mass and 200 parts by mass of n-butyl acetate was dispersed for 100 minutes in a horizontal sand mill using 1 mmφ glass beads, and a coating solution for forming a charge generation layer Got. The obtained coating solution was dip-coated on the undercoat layer and dried to form a charge generation layer having a thickness of 0.3 μm.

  Furthermore, 4 parts by mass of N, N′-diphenyl-N, N′-bis (3-methylphenyl)-[1,1 ′] biphenyl-4,4′-diamine and bisphenol Z polycarbonate resin (molecular weight 40,000) 6 60 parts by mass of tetrahydrofuran was dissolved by adding 60 parts by mass to obtain a coating solution for forming a charge transport layer. The obtained coating solution was dip-coated on the charge generation layer and dried at 145 ° C. for 30 minutes to form a charge transport layer having a thickness of 15 μm. Thereby, the electrophotographic photosensitive member of Example 1 was produced.

(Example 2)
1 part by weight of type I hydroxygallium phthalocyanine is wetted at 25 ° C. for 100 hours using a glass ball mill together with 20 parts by weight of N, N-dimethylformamide and 50 parts by weight of glass spherical media having an outer diameter of 0.9 mm. Grinded. Next, the obtained crystal was washed with acetone, dried, and in an X-ray diffraction spectrum using CuKα characteristic X-ray, a Bragg angle (2θ ± 0.2 °) of 7.5 ° and 28. 0.9 parts by mass of a hydroxygallium phthalocyanine pigment having a diffraction peak at 3 ° was obtained.

When the spectral absorption spectrum of the obtained hydroxygallium phthalocyanine pigment was measured, the maximum peak wavelength (λ _max ) in the range of 600 to 900 nm was present at 816 nm. Further, when this hydroxygallium phthalocyanine was observed using a transmission electron micrograph, it was confirmed that the number of particles having a particle size of 0.3 μm or more per 30 μm ² was 1 or less on the observed image. Moreover, it was 72.8 m < ² > / g when the BET specific surface area value was measured.

Instead of 20 parts by mass of the hydroxygallium phthalocyanine pigment having the maximum peak wavelength (λ _max ) of 824 nm in Example 1, 20 parts by mass of the hydroxygallium phthalocyanine pigment having the maximum peak wavelength (λ _max ) of 816 nm is used. An electrophotographic photosensitive member of Example 2 was produced in the same manner as Example 1 except that.

(Example 3)
Instead of 0.5 parts by mass of 1- (2-cyclohexanonyl) cyclohexanol represented by the above formula (3-1) in Example 1, a hydroxyketone compound represented by the above formula (3-2) was used. An electrophotographic photosensitive member of Example 3 was produced in the same manner as Example 1 except that.

Example 4
1 part by weight of type I hydroxygallium phthalocyanine, wet with 20 parts by weight of N, N-dimethylformamide and 40 parts by weight of glass spherical media with an outer diameter of 0.9 mm at 25 ° C. for 80 hours using a glass ball mill Grinded. Next, the obtained crystal was washed with acetone, dried, and in an X-ray diffraction spectrum using CuKα characteristic X-ray, a Bragg angle (2θ ± 0.2 °) of 7.5 ° and 28. 0.9 parts by mass of a hydroxygallium phthalocyanine pigment having a diffraction peak at 3 ° was obtained.

When the spectral absorption spectrum of the obtained hydroxygallium phthalocyanine pigment was measured, the maximum peak wavelength (λ _max ) in the range of 600 to 900 nm was present at 822 nm. Moreover, when this hydroxygallium phthalocyanine was observed using a transmission electron micrograph, it was confirmed that one or more particles having a particle size of 0.3 μm or more existed per 30 μm ² on the observed image. Moreover, it was 48.3 m < ² > / g when the BET specific surface area value was measured.

Instead of 20 parts by mass of the hydroxygallium phthalocyanine pigment having the maximum peak wavelength (λ _max ) of 824 nm in Example 1, 20 parts by mass of the hydroxygallium phthalocyanine pigment having the maximum peak wavelength (λ _max ) of 822 nm is used. An electrophotographic photosensitive member of Example 4 was produced in the same manner as Example 1 except that.

(Example 5)
1 part by mass of type I hydroxygallium phthalocyanine is wetted at 25 ° C. for 60 hours using a glass ball mill together with 20 parts by mass of N, N-dimethylformamide and 40 parts by mass of glass spherical media having an outer diameter of 0.9 mm. Grinded. Next, the obtained crystal was washed with acetone, dried, and in an X-ray diffraction spectrum using CuKα characteristic X-ray, a Bragg angle (2θ ± 0.2 °) of 7.5 ° and 28. 0.9 parts by mass of a hydroxygallium phthalocyanine pigment having a diffraction peak at 3 ° was obtained.

When the spectral absorption spectrum of the obtained hydroxygallium phthalocyanine pigment was measured, the maximum peak wavelength (λ _max ) in the range of 600 to 900 nm was present at 835 nm. Moreover, when this hydroxygallium phthalocyanine was observed using a transmission electron micrograph, it was confirmed that one or more particles having a particle size of 0.3 μm or more existed per 30 μm ² on the observed image. Moreover, it was 45.1 m < ² > / g when the BET specific surface area value was measured.

Instead of 20 parts by mass of the hydroxygallium phthalocyanine pigment having the maximum peak wavelength (λ _max ) of 824 nm in Example 1, 20 parts by mass of the hydroxygallium phthalocyanine pigment having the maximum peak wavelength (λ _max ) of 835 nm is used. An electrophotographic photosensitive member of Example 5 was produced in the same manner as Example 1 except that.

(Example 6)
1 part by mass of type I hydroxygallium phthalocyanine, 20 parts by mass of N, N-dimethylformamide, 0.03 part by weight of 1- (2-cyclohexanonyl) cyclohexanol represented by the above formula (3-1), and After wet grinding with a glass ball mill at 25 ° C. for 100 hours together with 50 parts by weight of glass spherical media having an outer diameter of 0.9 mm, washing with acetone and drying, CuKα characteristic X-rays were obtained. In the X-ray diffraction spectrum used, a hydroxygallium phthalocyanine pigment (complex with a hydroxyketone compound) having a diffraction peak at 7.5 ° and 28.3 ° at a Bragg angle (2θ ± 0.2 °) of 0.9 mass Got a part.

When the spectral absorption spectrum of the obtained hydroxygallium phthalocyanine pigment was measured, the maximum peak wavelength (λ _max ) in the range of 600 to 900 nm was present at 815 nm. Moreover, when this hydroxygallium phthalocyanine was observed using a transmission electron micrograph, it was confirmed that one or more particles having a particle size of 0.3 μm or more existed per 30 μm ² on the observed image. Moreover, it was 73.5 m < ² > / g when the BET specific surface area value was measured.

Instead of 20 parts by mass of the hydroxygallium phthalocyanine pigment having the maximum peak wavelength (λ _max ) of 824 nm in Example 1, 20 parts by mass of the hydroxygallium phthalocyanine pigment having the maximum peak wavelength (λ _max ) of 835 nm is used. An electrophotographic photosensitive member of Example 6 was produced in the same manner as Example 1 except that.

(Comparative Example 1)
1 part by mass of type I hydroxygallium phthalocyanine was wet-pulverized by stirring for 32 hours at 25 ° C. using a glass stirring tank having a stirring device together with 15 parts by weight of N, N-dimethylformamide. The obtained crystals were washed with acetone, dried, and the X-ray diffraction spectrum using CuKα characteristic X-rays showed Bragg angles (2θ ± 0.2 °) of 7.5 ° and 28.3 °. Thus, 0.9 part by mass of a hydroxygallium phthalocyanine pigment having a diffraction peak was obtained.

When the spectral absorption spectrum of the obtained hydroxygallium phthalocyanine pigment was measured, the maximum peak wavelength (λ _max ) in the range of 600 to 900 nm was present at 851 nm. Further, when this hydroxygallium phthalocyanine was observed using a transmission electron micrograph, it was confirmed that one or more particles having a particle diameter of 0.3 μm or more existed per 30 μm ² on the observation image. Moreover, it was 34.7 m < ² > / g when the BET specific surface area value was measured.

Instead of 20 parts by mass of the hydroxygallium phthalocyanine pigment having the maximum peak wavelength (λ _max ) of 822 nm in Example 4, 20 parts by mass of the hydroxygallium phthalocyanine pigment having the maximum peak wavelength (λ _max ) of 851 nm is used. The electrophotographic photosensitive member of Comparative Example 1 was prepared in the same manner as in Example 4 except that 0.5 part by mass of 1- (2-cyclohexanonyl) cyclohexanol represented by the above formula (3-1) was not used. Was made.

(Comparative Example 2)
1 part by mass of type I hydroxygallium phthalocyanine is wetted at 25 ° C. for 45 hours using a glass ball mill together with 20 parts by mass of N, N-dimethylformamide and 35 parts by mass of glass spherical media having an outer diameter of 0.9 mm. Grinded. Next, the obtained crystal was washed with acetone, dried, and in an X-ray diffraction spectrum using CuKα characteristic X-ray, a Bragg angle (2θ ± 0.2 °) of 7.5 ° and 28. 0.9 parts by mass of a hydroxygallium phthalocyanine pigment having a diffraction peak at 3 ° was obtained.

When the spectral absorption spectrum of the obtained hydroxygallium phthalocyanine pigment was measured, the maximum peak wavelength (λ _max ) in the range of 600 to 900 nm was present at 844 nm. Further, when this hydroxygallium phthalocyanine was observed using a transmission electron micrograph, it was confirmed that there were one or more particles having a particle size of 0.3 μm or more per 30 μm ² on the observed image. Moreover, it was 38.6 m < ² > / g when the BET specific surface area value was measured.

Instead of 20 parts by mass of the hydroxygallium phthalocyanine pigment having the maximum peak wavelength (λ _max ) of 835 nm in Example 5, 20 parts by mass of the hydroxygallium phthalocyanine pigment having the maximum peak wavelength (λ _max ) of 844 nm was used. The electrophotographic photosensitive member of Comparative Example 2 was prepared in the same manner as in Example 5 except that 0.5 part by mass of 1- (2-cyclohexanonyl) cyclohexanol represented by the above formula (3-1) was not used. Was made.

  The physical properties of the hydroxygallium phthalocyanine pigments used in the electrophotographic photoreceptors of Examples 1 to 6 and Comparative Examples 1 and 2 and the types of hydroxyketone compounds are summarized in Table 2 below.

(Image quality evaluation test and potential evaluation test)
The electrophotographic photosensitive drums obtained in Examples 1 to 6 and Comparative Examples 1 and 2 were mounted on full-color laser printers (DouCentreColor 400CP modified machine, manufactured by Fuji Xerox Co., Ltd.) each having the configuration shown in FIG. A photographic device was produced. In the above full-color laser printer, a roller charger (BCR) as a charging device, a ROS (Raster Output Scanner) using a 780 nm semiconductor laser as an exposure device, a two-component reversal development method as a development method, and a transfer device The roller charger (BTR) was used as the transfer device, and the belt intermediate transfer system was used as the transfer device, so that the potential (VL) after exposure could be measured, and the voltage applied to the BCR could be set arbitrarily. . Image formation was performed using this electrophotographic apparatus, and image quality (presence of fog and ghost) after initial printing and 10,000 sheets was evaluated according to the following evaluation criteria. The image was printed at a temperature of 20 ° C. and a humidity of 40%. Further, the post-exposure potential VL (V) was measured at the initial stage and after printing 10,000 sheets. The results are shown in Table 3.

<Fog evaluation>
Initially and after printing 10,000 sheets, the charging potential (VH) was changed variously to evaluate the fog on the entire white solid image. The fog was judged visually and graded as follows to obtain measured values. Of these, grades 2 and below are at a level that causes no particular problems in image quality.
Grade 0: No fogging is observed Grade 1: Fogging is extremely thin Grade 2: Fogging is thinly recognized Grade 3: Fogging is clearly recognized Grade 4: High fog is observed Grade 5: Fogging is extremely dark Be

<Ghost evaluation>
The ghost of the output image was evaluated initially and after printing 10,000 sheets. 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 ghost was judged visually and graded as follows to obtain measured values. Of these, grades 2 and below are at a level that causes no particular problems in image quality.
Grade 0: No ghost is recognized Grade 1: Ghost is extremely thin Grade 2: Ghost is thin Grade 3: Ghost is clearly recognized Grade 4: Ghost is deeply recognized Grade 5: Ghost is extremely dark Be

  As is apparent from the results shown in Table 3, according to the electrophotographic apparatus using the electrophotographic photosensitive member of Examples 1 to 6, it is compared with the electrophotographic apparatus using the electrophotographic photosensitive member of Comparative Examples 1 and 2. In addition, it is possible to maintain high sensitivity even after the initial use and after 10,000 times use, and the image characteristics are good since there is almost no image quality defect due to fog and ghost both in the initial time and after 10,000 use. It was confirmed that an output image was obtained. In Examples 4 and 5, compared to Examples 1 to 3 and 6, slight fog and ghosting occurred from the beginning, but no deterioration was observed after 10,000 times of use, and good image quality maintainability. It was confirmed that On the other hand, in Comparative Examples 1 and 2, fogging and ghosting occurred from the beginning, which worsened after 10,000 times, and it was confirmed that these image quality defects occurred severely.

  As described above, according to the electrophotographic photosensitive member of the present invention, it was confirmed that sufficient sensitivity can be obtained and image quality defects due to fogging and ghosting can be sufficiently suppressed.

(A)-(c) is a schematic cross section which shows 1st-3rd embodiment of the electrophotographic photoreceptor of this invention, respectively. (A)-(c) is a schematic cross section which shows 4th-6th embodiment of the electrophotographic photoreceptor of this invention, respectively. (A)-(c) is a schematic cross section which shows 7th-9th embodiment of the electrophotographic photoreceptor of this invention, respectively. (A)-(c) is a schematic cross section which shows 10th-12th embodiment of the electrophotographic photoreceptor of this invention, respectively. 1 is a schematic configuration diagram showing a preferred embodiment of an electrophotographic apparatus of the present invention. It is a schematic block diagram which shows other embodiment of the electrophotographic apparatus of this invention. It is a schematic block diagram which shows other embodiment of the electrophotographic apparatus of this invention. 1 is a schematic configuration diagram showing a preferred embodiment of a process cartridge of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1a, 1b ... Charge generation layer, 2 ... Charge transport layer, 3 ... Conductive support body, 4 ... Undercoat layer, 5 ... Protective layer, 6a, 6b ... Photosensitive layer, 7 ... Intermediate layer, 100, 105, 110, 115, 120, 125, 130, 135, 140, 145, 150, 155 ... electrophotographic photosensitive member, 200, 220, 230 ... electrophotographic device, 207 ... electrophotographic photosensitive member, 208 ... charging device, 209 ... power source, 210 DESCRIPTION OF SYMBOLS Exposure apparatus 211 ... Development apparatus 212 ... Transfer apparatus 213 Cleaning apparatus 214 ... Staticator 215 ... Fixing device 216 ... Mounting rail 217 ... Static discharge opening 218 ... Exposure Opening portion, 300 ... process cartridge, 400 ... housing, 402a to 402d ... charging roll, 403 ... laser light source (exposure device), 404a to 404d ... developing device, 405a to 405d ... toner cartridge, 406 ... drive roll, 407 ... tension roll, 408 ... backup roll, 409 ... intermediate transfer belt, 410a-410d ... primary transfer roll, 411 ... tray (transfer tray), 412 ... transfer Roll, 413 ... Secondary transfer roll, 414 ... Fixing roll, 415a to 415d ... Cleaning blade, 416 ... Cleaning blade, 500 ... Medium to be transferred.

Claims (9)

A conductive support;
A hydroxygallium phthalocyanine pigment provided on the conductive support and having a maximum peak wavelength in the range of 810 to 839 nm in the spectral absorption spectrum in the wavelength range of 600 to 900 nm, and represented by the following general formula (1) A photosensitive layer containing a hydroxyketone compound,
An electrophotographic photosensitive member comprising:

[In formula (1), R ¹ , R ² , R ³ and R ⁴ each independently represent a hydrocarbon group having 1 to 10 carbon atoms which may have a substituent. R ¹ and R ² , and R ³ and R ⁴ may be bonded to each other to form a ring. ]   2. The electrophotographic photosensitive member according to claim 1, wherein the spectral absorption spectrum of the photosensitive layer has an absorption peak wavelength in the range of 810 to 839 nm.   The electrophotographic photosensitive member according to claim 1 or 2, wherein the hydroxyketone compound is 1- (2-cyclohexanonyl) cyclohexanol.   The electrophotographic photoreceptor according to any one of claims 1 to 3, wherein the photosensitive layer contains a complex of the hydroxygallium phthalocyanine pigment and the hydroxyketone compound. A composite used as a constituent material of an electrophotographic photosensitive member, which has a maximum peak wavelength in a range of 810 to 839 nm in a spectral absorption spectrum in a wavelength range of 600 to 900 nm and the following general formula (1 And a hydroxyketone compound represented by the formula:

[In formula (1), R ¹ , R ² , R ³ and R ⁴ each independently represent a hydrocarbon group having 1 to 10 carbon atoms which may have a substituent. R ¹ and R ² , and R ³ and R ⁴ may be bonded to each other to form a ring. ] In an X-ray diffraction spectrum using CuKα characteristic X-rays, Bragg angles (2θ ± 0.2 °) of 6.9 °, 13.2 to 14.2 °, 16.5 °, 26.0 ° and 26.4 Or a type I hydroxygallium phthalocyanine pigment having diffraction peaks at 7.0 °, 13.4 °, 16.6 °, 26.0 ° and 26.7 °, or a Bragg angle (2θ ± 0.2 °) Wet pulverization of a mixture containing a V-type hydroxygallium phthalocyanine pigment having diffraction peaks at 7.5 ° and 28.3 °, a hydroxyketone compound represented by the following general formula (1), and a predetermined solvent A hydroxygallium phthalocyanine pigment having a maximum peak wavelength in the range of 810 to 839 nm in a spectral absorption spectrum in a wavelength range of 600 to 900 nm, characterized by having a wet pulverization treatment step Method for producing a complex between the hydroxy ketone compounds.

[In formula (1), R ¹ , R ² , R ³ and R ⁴ each independently represent a hydrocarbon group having 1 to 10 carbon atoms which may have a substituent. R ¹ and R ² , and R ³ and R ⁴ may be bonded to each other to form a ring. ]   7. The composite production according to claim 6, further comprising an acid pasting treatment step in which crude gallium phthalocyanine is subjected to an acid pasting treatment to obtain the type I hydroxygallium phthalocyanine pigment before the wet pulverization treatment step. Method. The electrophotographic photosensitive member according to any one of claims 1 to 4,
A charging means for charging the electrophotographic photosensitive member; a developing means for developing a latent electrostatic image formed on the electrophotographic photosensitive member with toner to form a toner image; and At least one selected from the group consisting of cleaning means for removing toner remaining on the surface;
A process cartridge comprising: The electrophotographic photosensitive member according to any one of claims 1 to 4,
Charging means for charging the electrophotographic photosensitive member;
Exposure means for forming an electrostatic latent image on the charged electrophotographic photosensitive member;
Developing means for developing the electrostatic latent image with toner to form a toner image;
Transfer means for transferring the toner image from the electrophotographic photosensitive member to a transfer target;
An electrophotographic apparatus comprising:

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