JP5534393B2 - Electrophotographic photoreceptor, image forming apparatus using the same, and process cartridge for image forming apparatus - Google Patents

Description

  The present invention relates to a highly stable photoconductor that is highly sensitive, can be used repeatedly, and can stably output an image in any environment, and an image forming apparatus using the same.

In recent years, the development of information processing system machines using electrophotography has been remarkable, and laser printers and digital copiers that record information using light by converting information into digital signals have significantly improved print quality and reliability. . These laser printers and digital copiers that are rapidly spreading have recently been rapidly demanded for high speed, high image quality, and high stability.

As an electrophotographic photosensitive member used in an image forming apparatus, an organic photosensitive material using an organic photosensitive material is generally widely applied for reasons such as cost, productivity, and low environmental load.

Various kinds of charge generating materials used in the organic photoreceptor have been developed, and pigments useful as photoreceptor characteristics such as azo pigments and phthalocyanine pigments have been found. Examples of the azo pigment include benzidine-based bisazo pigments described in, for example, Patent Document 1 (Japanese Patent Laid-Open No. 47-37543), Patent Document 2 (Japanese Patent Laid-Open No. 52-55643), and Patent Document 3 ( Stilbene bisazo pigments described in JP-A-52-8832), diphenylhexatriene-based bisazo pigments described in JP-A-58-222152, JP-A-58-222152. Diphenylbutadiene bisazo pigments described in JP-A-222153) are known.

As an example of the phthalocyanine pigment, the titanyl phthalocyanine pigment is described in α type described in Patent Document 6 (Japanese Patent Laid-Open No. 61-239248), and Patent Document 7 (Japanese Patent Laid-Open No. 1-17066). Type Y, Type I described in Patent Document 8 (Japanese Patent Laid-Open No. 61-109056), Type A described in Patent Document 9 (Japanese Patent Laid-Open No. 62-67094), Patent Document 10 (Japanese Patent Laid-Open No. 63-364) and Patent Document 11 (Japanese Patent Laid-Open No. 63-366), Type C, Patent Document 12 (Japanese Patent Laid-Open No. 2005-15682), Type B, Patent Examples include the m-type described in Document 13 (Japanese Patent Laid-Open No. 63-198067) and the quasi-amorphous type described in Patent Document 14 (Japanese Patent Laid-Open No. 1-123868). Specific examples of the metal-free phthalocyanine pigment include X-type metal-free phthalocyanine disclosed in Patent Document 15 (US Pat. No. 3,357,989), Patent Document 16 (Japanese Patent Application Laid-Open No. 58-182039). Examples of the disclosed τ-type metal-free phthalocyanine. Specific examples of the hydroxygallium phthalocyanine pigment are disclosed in Patent Document 17 (Japanese Patent Laid-Open No. 5-263007) and Patent Document 18 (Japanese Patent Laid-Open No. 5-279591). As specific examples of the copper phthalocyanine pigment, Patent Document 19 (Japanese Patent Laid-Open No. 58-100134), Patent Document 20 (Japanese Patent Laid-Open No. 61-273994), and Patent Document 21 (Japanese Patent Laid-Open No. 62-62367). ) And the like. Examples of the chlorogallium phthalocyanine pigment are disclosed in Patent Document 22 (Japanese Patent Laid-Open No. 59-44053) and Patent Document 23 (Japanese Patent Laid-Open No. 1-222159). Examples of chloroindium phthalocyanine pigments are disclosed in Patent Document 24 (Japanese Patent Laid-Open No. 60-59355).

  However, the photoreceptors using these single pigments have a narrow corresponding wavelength range, so the sensitivity to the light in the long wavelength range transmitted by the semiconductor laser, which is the mainstream of writing light for laser printers and copiers, is low, In addition, there are problems such as fluctuations in the characteristics of the photoconductor depending on the use environment and usage time, which is insufficient as a photoconductor for future high image quality or high-speed copying machines. In order to solve these problems, Patent Document 25 (JP-A-5-301292), Patent Document 26 (JP-A 2001-290296), a phthalocyanine compound and an azo pigment containing metal-free phthalocyanine and a fluorenone-based azo pigment. Patent Document 27 (Japanese Patent Laid-Open No. 9-127711) containing metal, Patent Document 28 (Japanese Patent Laid-Open No. 2002-23399) of mixed metal phthalocyanine and perylene pigment, and Patent Document 29 of Japanese Patent Laid-Open No. No. 334099), and titanyl phthalocyanine pigments and other phthalocyanine pigments, such as Patent Document 30 (Japanese Patent Laid-Open No. 3-9962), have been proposed to mix two or more kinds of pigments, but there are still no sufficient ones. .

  One reason for this is that the above-mentioned pigments generally have very low solubility in organic solvents, making it difficult to obtain highly dispersed uniform coating liquids, and purification is limited to washing steps with organic solvents. It is thought that it has not been removed.

The present applicant has proposed an azo pigment with improved solubility in an organic solvent (Patent Document 31 (Japanese Patent Laid-Open No. 2009-7523)), which enables the production of a photoreceptor with a uniform coating solution. It is difficult to obtain sufficient photoreceptor characteristics with a single charge generating material, and it is conceivable to use two or more types of charge generating materials having different electrical characteristics in combination.

In addition, it is considered that the method of mixing a plurality of pigments is mainly mechanical means such as milling, cannot be mixed / combined at the molecular level, and has not sufficiently exhibited the function as an organic photoconductor. . In addition, a method using an acid paste is also proposed, but since concentrated sulfuric acid is used, there are problems in production, and there is a concern about decomposition and the application to pigments is limited. Also, phthalocyanine pigments whose properties vary greatly depending on the crystal type, when mixed during acid paste, crystal transition occurs or the desired crystal type cannot be obtained, resulting in sufficient photoreceptor characteristics. There was also a problem that it could not be obtained.
Therefore, in order to realize an electrophotographic photoreceptor that overcomes the conventional drawbacks, a more excellent charge generating material is desired.

  It is an object of the present invention to realize high-quality printing without image defects for a long period of time by suppressing charge accumulation in the electrophotographic photosensitive member caused by the charge generation material, and to achieve stable image quality in any environment. It is an object of the present invention to provide an electrophotographic photosensitive member and an image forming apparatus capable of realizing the above output.

The present invention is solved by the following (1) to (10).
(1) At least a photosensitive layer is provided on a conductive support, and the photosensitive layer coexists with an azo compound having a carboester group represented by the following general formula (I) dissolved in a solvent and a phthalocyanine pigment. in is obtained by de-carbo esterified electrophotographic photoreceptor characterized by comprising a composite phthalocyanine pigments of the azo compound and a phthalocyanine pigment represented by the following general formula (a).

［但し式（Ｉ）中、Ａはアゾ化合物の残基であり、この残基Ａは、１つまたはそれ以上のヘテロ原子を介してｎ個のＥ基に結合しており、そしてこれらのヘテロ原子は、ＮおよびＯからなる群から選ばれ、残基Ａの一部を形成しており、Ｅ基は独立してＨ（水素原子）または次式で示されるカルボエステル基：−Ｃ（＝Ｏ）−Ｏ−Ｒ₁〔式中Ｒ₁は、炭素数４から１０の置換または非置換のアルキル基、アルケニル基、アルキニル基、シクロアルキル基、シクロアルケニル基、またはアラルキル基を表わす。〕を表わす。ただし、Ｅ基の全てが同時に水素原子であることはない。ｎは、１から９の整数である。］

[Wherein A is a residue of an azo compound, and this residue A is bonded to n E groups via one or more heteroatoms, and The atom is selected from the group consisting of N and O and forms part of the residue A, and the E group is independently H (hydrogen atom) or a carboester group represented by the following formula: —C (= O) —O—R ₁ [wherein R ₁ represents a substituted or unsubstituted alkyl group, alkenyl group, alkynyl group, cycloalkyl group, cycloalkenyl group, or aralkyl group having 4 to 10 carbon atoms. ]. However, not all E groups are hydrogen atoms at the same time. n is an integer from 1 to 9. ]

［但し式（ａ）中、Ａは一般式（Ｉ）と同義であり、Ｈは水素原子を表わし、ｎは、１から９の整数である。］
（２）前記一般式（Ｉ）および前記一般式（ａ）で表されるアゾ化合物が、下記一般式（２）で示される残基Ａを有するアゾ化合物であることを特徴とする、前記（１）に記載の電子写真感光体。

[In the formula (a), A is as defined in the general formula (I), H represents a hydrogen atom, and n is an integer of 1 to 9. ]
(2) The azo compound represented by the general formula (I) and the general formula (a) is an azo compound having a residue A represented by the following general formula (2), The electrophotographic photosensitive member according to 1).

（ただし、Ｂはアゾ化合物の主骨格を示し、Ｃｐはカップラー成分残基であり、ｍは２又は３の整数を表わす。）
（３）前記Ｃｐが下記一般式（３）乃至（１１）の少なくともいずれかで表わされるカップラー成分残基であることを特徴とする前記（２）に記載の電子写真感光体。

(B represents the main skeleton of the azo compound, Cp represents a coupler component residue, and m represents an integer of 2 or 3.)
(3) The electrophotographic photosensitive member according to (2), wherein the Cp is a coupler component residue represented by at least one of the following general formulas (3) to (11).

上記一般式（３）〜（６）中、Ｘ、Ｙ^１、Ｚ、ｐおよびｑはそれぞれ以下のものを表わす。
Ｘ：−ＯＨ、−Ｎ（Ｒ^１）（Ｒ^２）または−ＮＨＳＯ_２−Ｒ^３。
（ただしここで、Ｒ^１およびＲ^２は水素原子または置換もしくは無置換のアルキル基を表わし、Ｒ^３は置換もしくは無置換のアルキル基または置換もしくは無置換のアリール基を表わす。）
Ｙ^１：水素原子、ハロゲン原子、置換もしくは無置換のアルキル基、置換もしくは無置換のアルコキシ基、カルボキシ基、スルホン基、置換もしくは無置換のスルファモイル基または−ＣＯＮ（Ｒ^４）（Ｙ^２）。［Ｒ^４は水素原子、アルキル基もしくはその置換体またはフェニル基もしくはその置換体を表わし、Ｙ^２は炭化水素環基もしくはその置換体、複素環基もしくはその置換体、または−Ｎ＝Ｃ（Ｒ^５）（Ｒ^６）（但し、Ｒ^５は炭化水素環基もしくはその置換体、複素環基もしくはその置換体またはスチリル基もしくはその置換体、Ｒ^６は水素原子、アルキル基またはフェニル基もしくはその置換体を表わすか、あるいはＲ^５およびＲ^６はそれらに結合する炭素原子と共に環を形成してもよい。）を示す。］
Ｚ：炭化水素環もしくはその置換体または複素環もしくはその置換体。
ｐ：１または２の整数。
ｑ：１または２の整数。

In the general formulas (3) to (6), X, Y ¹ , Z, p and q each represent the following.
^{X: -OH, -N (R 1} ) (R 2) or -NHSO ₂ -R ^3.
(Here, R ¹ and R ² represent a hydrogen atom or a substituted or unsubstituted alkyl group, and R ³ represents a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group.)
Y ¹ : a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a carboxy group, a sulfone group, a substituted or unsubstituted sulfamoyl group, or —CON (R ⁴ ) (Y ² ). [R ⁴ represents a hydrogen atom, an alkyl group or a substituted product thereof, or a phenyl group or a substituted product thereof, Y ² represents a hydrocarbon ring group or a substituted product thereof, a heterocyclic group or a substituted product thereof, or —N═C (R ⁵ ) (R ⁶ ) (where R ⁵ is a hydrocarbon ring group or a substituted product thereof, a heterocyclic group or a substituted product thereof, or a styryl group or a substituted product thereof, and R ⁶ is a hydrogen atom, an alkyl group, a phenyl group or a substituted product thereof. Or R ⁵ and R ⁶ may form a ring together with the carbon atom to which they are attached. ]
Z: A hydrocarbon ring or a substituted product thereof, or a heterocyclic ring or a substituted product thereof.
p: an integer of 1 or 2.
q: An integer of 1 or 2.

（上式中、Ｒ^７は置換もしくは無置換の炭化水素基を表わし、Ｘは前記と同じである。）

(In the above formula, R ⁷ represents a substituted or unsubstituted hydrocarbon group, and X is as defined above.)

（上式中、Ａは、式（８）中に記載された２個のＮ原子と共にＮ含有ヘテロ環を形成するに必要な芳香族炭化水素の２価基または窒素原子を環内に含むヘテロ原子含有の２価基を表わす（これらの環は置換または無置換でもよい）。Ｘは前記と同じ。）

(In the above formula, A is a heterocycle containing a divalent aromatic hydrocarbon group or a nitrogen atom necessary for forming an N-containing heterocycle together with the two N atoms described in formula (8). Represents an atom-containing divalent group (these rings may be substituted or unsubstituted. X is as defined above.)

（上式中、Ｒ^８はアルキル基、カルバモイル基、カルボキシ基またはそのエステルを表わし、Ａｒ^１は炭化水素環基またはその置換体を表わし、Ｘは前記と同じである。）

(In the above formula, R ⁸ represents an alkyl group, a carbamoyl group, a carboxy group or an ester thereof, Ar ¹ represents a hydrocarbon ring group or a substituent thereof, and X is the same as described above.)

（上記式（１０）および（１１）中、Ｒ^９は水素原子または置換もしくは無置換の炭化水素基を表わし、Ａｒ^２は炭化水素環基またはその置換体を表わす。但し、同時にＲ^９が水素原子でかつＡｒ^２がシクロアルキル基又はシクロアルケニル基になることはない。
（４）前記一般式（２）で示されるアゾ化合物において、Ｂが下記一般式（１２）で示されることを特徴とする前記第（２）または第（３）に記載の電子写真感光体。

(In the formula (10) and (11), R ⁹ represents a hydrogen atom or a substituted or unsubstituted hydrocarbon group, Ar ² represents a hydrocarbon ring group or a substitution product thereof. However, at the same time R ⁹ is hydrogen It is an atom and Ar ² does not become a cycloalkyl group or a cycloalkenyl group.
(4) In the azo compound represented by the general formula (2), B is represented by the following general formula (12). The electrophotographic photosensitive member as described in the above (2) or (3).

（ただし、Ｒ^１１，Ｒ^１２は独立して、水素原子、ハロゲン原子、置換もしくは無置換のアルキル基、置換もしくは無置換のアルコキシ基、カルボキシル基またはそのエステルを表わす。）
（５）前記一般式（２）で示されるアゾ化合物において、Ｂが下記一般式（１３）で示されることを特徴とする前記第（２）または第（３）に記載の電子写真感光体。

(However, R ¹¹ and R ¹² independently represent a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a carboxyl group, or an ester thereof.)
(5) The electrophotographic photosensitive member according to (2) or (3), wherein in the azo compound represented by the general formula (2), B is represented by the following general formula (13).

（ただし、Ｒ^１９，Ｒ^２０は独立して、水素原子、ハロゲン原子、置換もしくは無置換のアルキル基、置換もしくは無置換のアルコキシ基、カルボキシル基及びそのエステルを表わす。）
（６）前記一般式（２）で示されるアゾ化合物において、Ｂが下記一般式（１４）で示されることを特徴とする前記第（２）または第（３）に記載の電子写真感光体。

(However, R ¹⁹ and R ²⁰ independently represent a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a carboxyl group, and an ester thereof.)
(6) The electrophotographic photosensitive member according to (2) or (3), wherein in the azo compound represented by the general formula (2), B is represented by the following general formula (14).

（ただし、Ｒ^２４，Ｒ^２５，Ｒ^２６は独立して、水素原子、ハロゲン原子、置換もしくは無置換のアルキル基、置換もしくは無置換のアルコキシ基、カルボキシル基及びそのエステルを表わす。）
（７）前記フタロシアニン顔料が少なくとも下記構造式で示されるチタニルフタロシアニンを含有したものであることを特徴とする前記第（１）乃至第（６）のいずれかに記載の電子写真感光体。

(However, R ²⁴ , R ²⁵ , and R ²⁶ independently represent a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a carboxyl group, and an ester thereof.)
(7) The electrophotographic photosensitive member according to any one of (1) to (6), wherein the phthalocyanine pigment contains at least titanyl phthalocyanine represented by the following structural formula.

（式中、Ｍは、ＴｉＯであり、Ｘ_１〜Ｘ_１６はそれぞれ同じでも異なっていてもよい水素原子、ハロゲン原子、水酸基、ニトロ基、シアノ基、エステル基、アルキル基、アルケニル基、アルコキシル基、アリール基、アリーロキシル基を示す。）
（８）少なくとも帯電手段、露光手段、現像手段、転写手段、及び電子写真感光体を有する画像形成装置において、該電子写真感光体が前記（１）乃至第（７）のいずれかに記載の電子写真感光体であることを特徴とする画像形成装置。
（９）電子写真感光体と、帯電手段、露光手段、現像手段、転写手段、及びクリーニング手段から選ばれる少なくとも１つの手段とが一体となったカートリッジを搭載し、かつ該カートリッジが装置本体に対し着脱自在であることを特徴とする請求項８に記載の画像形成装置。
（１０）電子写真感光体と、帯電手段、露光手段、現像手段、転写手段、及びクリーニング手段から選ばれる少なくとも１つの手段とが一体となったカートリッジにおいて、該電子写真感光体が前記第（１）乃至第（７）のいずれかに記載の電子写真感光体であることを特徴とする画像形成装置用プロセスカートリッジ。

(In the formula, M is TiO, and X _{1 to} X ₁₆ may be the same or different from each other, hydrogen atom, halogen atom, hydroxyl group, nitro group, cyano group, ester group, alkyl group, alkenyl group, alkoxyl group. Represents an aryl group or an aryloxyl group.)
(8) In an image forming apparatus having at least a charging unit, an exposure unit, a developing unit, a transfer unit, and an electrophotographic photosensitive member, the electrophotographic photosensitive member is an electron according to any one of (1) to (7). An image forming apparatus characterized by being a photographic photoreceptor.
(9) A cartridge in which an electrophotographic photosensitive member and at least one means selected from a charging means, an exposure means, a developing means, a transfer means, and a cleaning means are integrated is mounted, and the cartridge is attached to the apparatus main body. The image forming apparatus according to claim 8, wherein the image forming apparatus is detachable.
(10) In a cartridge in which an electrophotographic photosensitive member is integrated with at least one unit selected from a charging unit, an exposure unit, a developing unit, a transfer unit, and a cleaning unit, the electrophotographic photosensitive member is the first (1). A process cartridge for an image forming apparatus, which is the electrophotographic photosensitive member according to any one of (1) to (7).

According to the present invention, there is provided an electrophotographic photoreceptor and an image forming apparatus capable of outputting a high-quality print without image defects over a long period of time by using a composite phthalocyanine pigment in the photosensitive layer in the electrophotographic photoreceptor. It came to do.

  Here, the composite phthalocyanine pigment in the present invention means that at least one azo compound represented by the general formula (1) is dissolved in an organic solvent in the coexistence of the phthalocyanine pigment, and the azo compound and the phthalocyanine pigment are made into molecules. The product produced by decarboesterification using chemical, thermal, or photolytic means in the state of contact at a level.

  Therefore, the composite phthalocyanine pigment of the present invention has a highly dispersed phthalocyanine pigment at the molecular level and has bonding even if it is an azo pigment having low solubility in an organic solvent that is difficult to achieve high dispersion. This is basically different from the mixture of pigments by milling as known in the prior art, and achieves higher sensitivity and image stabilization that could not be achieved with conventional ones. is there.

There are various reasons why such an effect is manifested. For example, by covering the phthalocyanine pigment, which is likely to be transferred to low-sensitivity crystals, with an azo pigment, depending on the selected azo pigment, an extremely stable charge generating material whose characteristics are hardly changed by an external factor can be obtained. An electrophotographic photosensitive member having stable image quality can be obtained even under an environment.
In other words, a major problem with charge generation layer coating liquids is the stability of pigments, which limits the formulation of pigments and charge generation layer coating liquids that can be used as charge generation materials. There was a part that was sacrificed. Particularly in phthalocyanine pigments, as represented by Y-type titanyl phthalocyanine pigments, the sensitivity is very high, but the crystal stability is low, so that sufficient characteristics cannot be obtained.
Specifically, in the charge generation layer coating solution, do not make the binder resin rich in order to maintain sufficient crystal stability, or reduce the particle size sufficiently to suppress the share in consideration of the crystal transition at the time of preparing the dispersion. These methods are used as they are, and adversely affect the photoreceptor characteristics such as sensitivity.
However, in the composite phthalocyanine pigment of the present invention, since the crystal stability of the phthalocyanine pigment is increased by wrapping the surroundings of the desired crystal type phthalocyanine pigment with an azo pigment, the method as described above is used to maintain the crystal type. Therefore, it is possible to prepare a highly dispersed coating solution having a small particle size, and it becomes possible to design a formulation with better electrophotographic characteristics.

In general, a phthalocyanine pigment having a low electron transport capability has a problem that in a charge generation layer using the phthalocyanine pigment alone, charges are easily trapped and the potential is likely to fluctuate in repeated use.
In order to solve this, there is a technique in which an n-type pigment is mixed and used by milling or the like, or an electron transporting material is dispersed in the charge generation layer, but the composite phthalocyanine pigment of the present invention has a phthalocyanine pigment. N-type azo pigments having an electron-withdrawing structure at the molecular level can be bonded to each other, and high sensitivity and potential stability that cannot be achieved by the prior art can be exhibited.

Also known is a method of mixing other pigments during the acid paste of the pigment, but it is difficult to control the crystal form of the phthalocyanine pigment, and the desired crystal form cannot be obtained and sufficient photoreceptor characteristics are obtained. In many cases, however, in the composite phthalocyanine pigment of the present invention, the azo pigment is bonded to the desired crystal type phthalocyanine pigment at the molecular level, so that such a problem has been solved.

As described above, by using the composite phthalocyanine pigment, various problems have been overcome so far. As a result, the electrophotographic photosensitive member is highly sensitive and has a very stable potential regardless of the usage environment. In addition, an image forming apparatus excellent in image quality stability has been provided.

FIG. 1 is a diagram showing the layer structure of the electrophotographic photosensitive member of the present invention. FIG. 2 is a diagram showing the layer structure of another electrophotographic photosensitive member used in the present invention. FIG. 3 is a diagram showing the layer structure of another electrophotographic photosensitive member used in the present invention. FIG. 4 is a diagram showing the layer structure of another electrophotographic photosensitive member used in the present invention. FIG. 5 is a diagram for explaining the electrophotographic process and the image forming apparatus of the present invention. FIG. 6 is a view for explaining the charging means of the present invention. FIG. 7 is a diagram for explaining another electrophotographic process and an image forming apparatus of the present invention. FIG. 8 is a diagram for explaining a process cartridge for an image forming apparatus according to the present invention. 3 is an XRD pattern of titanyl phthalocyanine synthesized in Synthesis Example 1. FIG.

Next, the photoreceptor of the present invention will be described below with reference to the drawings.
As shown in FIG. 1, the photoreceptor (1) of the present invention comprises, on a conductive support (2), a charge generation layer (3) containing a charge generation material as a main component and a charge transport material as a main component. The charge transport layer (4) to be stacked is laminated.
As shown in FIG. 2, the photoreceptor (1) of the present invention has an undercoat layer (6) or an intermediate layer between the conductive support (2) and the charge generation layer (3). It may be formed.
In the photoreceptor (1) of the present invention, a protective layer (5) may be formed on the charge transport layer (4) as shown in FIG.
Further, as shown in FIG. 4, the photoreceptor (1) of the present invention has a single photosensitive layer (7) containing a charge generating substance and a charge transporting substance on a conductive support (2). You may make the aspect of a layer type photoreceptor.

<Conductive support>
Examples of the conductive support include those having a volume resistance of 10 ¹⁰ Ω · cm or less, such as metals such as aluminum, nickel, chromium, nichrome, copper, gold, silver, and platinum, tin oxide, and indium oxide. Metal oxide coated by film or cylindrical plastic or paper by vapor deposition or sputtering, or a plate made of aluminum, aluminum alloy, nickel, stainless steel, etc. After the conversion, a tube subjected to surface treatment such as cutting, superfinishing or polishing can be used. Endless nickel belts and endless stainless steel belts can also be used as the conductive support.

In addition, the conductive support dispersed in an appropriate binder resin on the support can be used as the conductive support of the present invention.
Examples of the conductive powder include carbon black, acetylene black, metal powder such as aluminum, nickel, iron, nichrome, copper, zinc, and silver, or metal oxide powder such as conductive tin oxide and ITO. It is done.
The binder resin used at the same time includes polystyrene, styrene-acrylonitrile copolymer, styrene-butadiene copolymer, styrene-maleic anhydride copolymer, polyester, polyvinyl chloride, vinyl chloride-vinyl acetate copolymer, Polyvinyl acetate, polyvinylidene chloride, polyarylate resin, phenoxy resin, polycarbonate, cellulose acetate resin, ethyl cellulose resin, polyvinyl butyral, polyvinyl formal, polyvinyl toluene, poly-N-vinylcarbazole, acrylic resin, silicone resin, epoxy resin, melamine Thermoplastic, thermosetting resin or photo-curing resin such as resin, urethane resin, phenol resin, alkyd resin and the like can be mentioned.
Such a conductive layer can be provided by dispersing and applying these conductive powder and binder resin in a suitable solvent such as tetrahydrofuran, dichloromethane, methyl ethyl ketone, and toluene.

Further, a heat shrinkable tube in which the conductive powder is contained in a material such as polyvinyl chloride, polypropylene, polyester, polystyrene, polyvinylidene chloride, polyethylene, chlorinated rubber, polytetrafluoroethylene-based fluororesin on a suitable cylindrical substrate. Those provided with a conductive layer can be used favorably as the conductive support of the present invention.

<Photosensitive layer>
Next, the photosensitive layer will be described.
The laminated photosensitive layer is constituted by sequentially laminating at least a charge generation layer and a charge transport layer.

<Charge generation layer>
The charge generation layer is a layer containing a charge generation material. The charge generation material contains at least the composite phthalocyanine pigment used in the present invention.
The composite phthalocyanine pigment used in the present invention is an azo compound represented by the following general formula (a) by decarboxylating an azo compound having a carboester group represented by the following general formula (I). And a phthalocyanine pigment.

［但し式（Ｉ）中、Ａはアゾ化合物の残基であり、この残基Ａは、１つまたはそれ以上のヘテロ原子を介してｎ個のＥ基に結合しており、そしてこれらのヘテロ原子は、ＮおよびＯからなる群から選ばれ、残基Ａの一部を形成しており、Ｅ基は独立してＨ（水素原子）または次式で示されるカルボエステル基：−Ｃ（＝Ｏ）−Ｏ−Ｒ₁〔式中Ｒ₁は、炭素数４から１０の置換または非置換のアルキル基、アルケニル基、アルキニル基、シクロアルキル基、シクロアルケニル基、またはアラルキル基を表わす。〕を表わす。ただし、Ｅ基の全てが同時に水素原子であることはない。ｎは、１から９の整数である。］

[Wherein A is a residue of an azo compound, and this residue A is bonded to n E groups via one or more heteroatoms, and The atom is selected from the group consisting of N and O and forms part of the residue A, and the E group is independently H (hydrogen atom) or a carboester group represented by the following formula: —C (= O) —O—R ₁ [wherein R ₁ represents a substituted or unsubstituted alkyl group, alkenyl group, alkynyl group, cycloalkyl group, cycloalkenyl group, or aralkyl group having 4 to 10 carbon atoms. ]. However, not all E groups are hydrogen atoms at the same time. n is an integer from 1 to 9. ]

［但し式（ａ）中、Ａは一般式（Ｉ）と同義であり、Ｈは水素原子を表わし、ｎは、１から９の整数である。］

[In the formula (a), A is as defined in the general formula (I), H represents a hydrogen atom, and n is an integer of 1 to 9. ]

As a means for compounding, a phthalocyanine pigment is added to a solution of the azo compound represented by the general formula (1), and the azo compound is combined with a chemical means, thermal condition in a state where the azo compound and the phthalocyanine pigment coexist. Means for decarboesterification and complexing using at least one of means and photolytic means are preferred.

  As an azo pigment that can be preferably used in the present invention, the residue A of the azo compound represented by the general formula (I) and the general formula (a) is an azo compound represented by the following general formula (2). is there.

（ただし、Ｂはアゾ化合物の主骨格を示し、Ｃｐはカップラー成分残基であり、ｍは２又は３の整数を表わす。）

(B represents the main skeleton of the azo compound, Cp represents a coupler component residue, and m represents an integer of 2 or 3.)

More preferably, Cp in the general formula (2) is a coupler component residue represented by at least one of the following general formulas (3) to (11).

上記一般式（３）〜（６）中、Ｘ、Ｙ^１、Ｚ、ｐおよびｑはそれぞれ以下のものを表わす。
Ｘ：−ＯＨ、−Ｎ（Ｒ^１）（Ｒ^２）または−ＮＨＳＯ_２−Ｒ^３。
（ただしここで、Ｒ^１およびＲ^２は水素原子または置換もしくは無置換のアルキル基を表わし、Ｒ^３は置換もしくは無置換のアルキル基または置換もしくは無置換のアリール基を表わす。）
Ｙ^１：水素原子、ハロゲン原子、置換もしくは無置換のアルキル基、置換もしくは無置換のアルコキシ基、カルボキシ基、スルホン基、置換もしくは無置換のスルファモイル基または−ＣＯＮ（Ｒ^４）（Ｙ^２）。［Ｒ^４は水素原子、アルキル基もしくはその置換体またはフェニル基もしくはその置換体を表わし、Ｙ^２は炭化水素環基もしくはその置換体、複素環基もしくはその置換体、または−Ｎ＝Ｃ（Ｒ^５）（Ｒ^６）（但し、Ｒ^５は炭化水素環基もしくはその置換体、複素環基もしくはその置換体またはスチリル基もしくはその置換体、Ｒ^６は水素原子、アルキル基またはフェニル基もしくはその置換体を表わすか、あるいはＲ^５およびＲ^６はそれらに結合する炭素原子と共に環を形成してもよい。）を示す。］
Ｚ：炭化水素環もしくはその置換体または複素環もしくはその置換体。
ｐ：１または２の整数。
ｑ：１または２の整数。

In the general formulas (3) to (6), X, Y ¹ , Z, p and q each represent the following.
^{X: -OH, -N (R 1} ) (R 2) or -NHSO ₂ -R ^3.
(Here, R ¹ and R ² represent a hydrogen atom or a substituted or unsubstituted alkyl group, and R ³ represents a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group.)
Y ¹ : a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a carboxy group, a sulfone group, a substituted or unsubstituted sulfamoyl group, or —CON (R ⁴ ) (Y ² ). [R ⁴ represents a hydrogen atom, an alkyl group or a substituted product thereof, or a phenyl group or a substituted product thereof, Y ² represents a hydrocarbon ring group or a substituted product thereof, a heterocyclic group or a substituted product thereof, or —N═C (R ⁵ ) (R ⁶ ) (where R ⁵ is a hydrocarbon ring group or a substituted product thereof, a heterocyclic group or a substituted product thereof, or a styryl group or a substituted product thereof, and R ⁶ is a hydrogen atom, an alkyl group, a phenyl group or a substituted product thereof. Or R ⁵ and R ⁶ may form a ring together with the carbon atom to which they are attached. ]
Z: A hydrocarbon ring or a substituted product thereof, or a heterocyclic ring or a substituted product thereof.
p: an integer of 1 or 2.
q: An integer of 1 or 2.

（上式中、Ｒ^７は置換もしくは無置換の炭化水素基を表わし、Ｘは前記と同じである。）

(In the above formula, R ⁷ represents a substituted or unsubstituted hydrocarbon group, and X is as defined above.)

（上式中、Ａは、式（８）中に記載された２個のＮ原子と共にＮ含有ヘテロ環を形成するに必要な芳香族炭化水素の２価基または窒素原子を環内に含むヘテロ原子含有の２価基を表わす（これらの環は置換または無置換でもよい）。Ｘは前記と同じ。）

(In the above formula, A is a heterocycle containing a divalent aromatic hydrocarbon group or a nitrogen atom necessary for forming an N-containing heterocycle together with the two N atoms described in formula (8). Represents an atom-containing divalent group (these rings may be substituted or unsubstituted. X is as defined above.)

（上式中、Ｒ^８はアルキル基、カルバモイル基、カルボキシ基またはそのエステルを表わし、Ａｒ１は炭化水素環基またはその置換体を表わし、Ｘは前記と同じである。）

(In the above formula, R ⁸ represents an alkyl group, a carbamoyl group, a carboxy group or an ester thereof, Ar 1 represents a hydrocarbon ring group or a substituent thereof, and X is the same as described above.)

（上記式（１０）および（１１）中、Ｒ^９は水素原子または置換もしくは無置換の炭化水素基を表わし、Ａｒ^２は炭化水素環基またはその置換体を表わす。但し、同時にＲ^９が水素原子でかつＡｒ^２がシクロアルキル基又はシクロアルケニル基になることはない。

(In the formula (10) and (11), R ⁹ represents a hydrogen atom or a substituted or unsubstituted hydrocarbon group, Ar ² represents a hydrocarbon ring group or a substitution product thereof. However, at the same time R ⁹ is hydrogen It is an atom and Ar ² does not become a cycloalkyl group or a cycloalkenyl group.

More preferably, B in the general formula (2) is an azo compound represented by the following general formulas (12) to (14). Since these azo compounds generally exhibit n-type characteristics, when combined with a phthalocyanine pigment, they are very effective for obtaining the effects expected of the present invention.

（ただし、Ｒ^１１，Ｒ^１２は独立して、水素原子、ハロゲン原子、置換もしくは無置換のアルキル基、置換もしくは無置換のアルコキシ基、カルボキシル基またはそのエステルを表わす。）

(However, R ¹¹ and R ¹² independently represent a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a carboxyl group, or an ester thereof.)

（ただし、Ｒ^１９，Ｒ^２０は独立して、水素原子、ハロゲン原子、置換もしくは無置換のアルキル基、置換もしくは無置換のアルコキシ基、カルボキシル基及びそのエステルを表わす。）

(However, R ¹⁹ and R ²⁰ independently represent a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a carboxyl group, and an ester thereof.)

（ただし、Ｒ^２４，Ｒ^２５，Ｒ^２６は独立して、水素原子、ハロゲン原子、置換もしくは無置換のアルキル基、置換もしくは無置換のアルコキシ基、カルボキシル基及びそのエステルを表わす。）
該Ｅ基は下記のカルボエステル基：−Ｃ（＝Ｏ）−Ｏ−Ｒ^１（式中Ｒ^１は、炭素数４から１０の置換または非置換のアルキル基、アルケニル基、アルキニル基、シクロアルキル基、シクロアルケニル基、またはアラルキル基を表わす。）を表わす。ｎは、１から９の整数である。〕

(However, R ²⁴ , R ²⁵ , and R ²⁶ independently represent a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a carboxyl group, and an ester thereof.)
The E group is the following carboester group: —C (═O) —O—R ¹ (wherein R ¹ is a substituted or unsubstituted alkyl group, alkenyl group, alkynyl group, cycloalkyl group having 4 to 10 carbon atoms). Represents a group, a cycloalkenyl group, or an aralkyl group. n is an integer from 1 to 9. ]

As a preferable compound of the azo compound represented by the general formula (I) or the general formula (a) that can be used in the present invention, the main skeleton of the azo compound is the formula (12) -1 to (12) -1 to ( 12) -14, Formula (13) -1 to (13) -5 in which the main skeleton of the azo compound is General Formula (13), Formula (14) -1 in which the main skeleton of the azo compound is General Formula (14) To (14) -5.
Examples of compounds are shown below. E is hydrogen or a carboester group: —C (═O) —O—R1 (wherein R1 is a substituted or unsubstituted alkyl group, alkenyl group, alkynyl group, cycloalkyl group, cycloalkenyl group having 4 to 10 carbon atoms) Represents a group or an aralkyl group.

<Examples of compounds in which the main skeleton of the azo compound is the general formula (12)>

＜アゾ化合物の主骨格が一般式（１３）である化合物の例＞

<Examples of compounds in which the main skeleton of the azo compound is the general formula (13)>

＜アゾ化合物の主骨格が一般式（１４）である化合物の例＞

<Examples of compounds in which the main skeleton of the azo compound is the general formula (14)>

  The compound of the formula (I) having a carboester group can be synthesized, for example, as described in European Patent No. 648770 and European Patent No. 648817, and Japanese Translation of PCT International Publication No. 2001-513119. In the protic organic solvent, in the presence of a base as a catalyst, at a temperature of 0 to 150 ° C., preferably 10 to 100 ° C., for 30 minutes to 20 hours, a compound of the above general formula (2) and a compound of the following formula (15) Can be synthesized at a suitable molar ratio.

（Ｂ，Ｃｐ，Ｒ_１は前記に記載のとおりである）
それぞれの場合において、モル比は導入されるＥの数に左右される。好ましくはピロ炭酸ジエステルを少し過剰に用いるのが適している。

(B, Cp, R ₁ are as described above)
In each case, the molar ratio depends on the number of E introduced. Preferably, the pyrocarbonic acid diester is used in a slight excess.

Suitable aprotic organic solvents include, for example, ether solvents such as tetrahydrofuran or dioxane, or glycol ether solvents such as ethylene glycol methyl ether and ethylene glycol ethyl ether, or acetonitrile, N, N-dimethylformamide, N, N- Examples include dimethylacetamide, ethyl cellosolve, ethyl acetate, methyl acetate, dichloromethane, dichloroethane, monochlorobenzene, toluene, xylene, nitrobenzene, pyridine, picoline or quinoline. Preferred solvents are pyridine, tetrahydrofuran, N, N-dimethylformamide, N, N-dimethylacetamide.

Suitable bases as catalysts are, for example, alkali metals: sodium, potassium, etc., and their hydroxides and carbonates, or alkali metal amides, sodium amides, potassium amides, and alkali metal hydrides, such as Examples include lithium hydride. As the organic aliphatic, aromatic or heterocyclic N-bases, diazabicyclooctene, diazabicycloundecene, 4-dimethylaminopyridine, dimethylpyridine, pyridine, triethylamine and the like can be used. Preferred are organic N-bases such as 4-dimethylaminopyridine, dimethylpyridine and pyridine.

The pyrocarbonic acid diester represented by the above formula (15) can be produced by a generally known method. It is also commercially available. R ₁ is as described above, and is preferably a branched alkyl group from the viewpoint of surprising improvement in solubility.

The phthalocyanine pigment used in the present invention may be any one, but preferably titanyl phthalocyanine, copper phthalocyanine, hydroxygallium phthalocyanine, chlorogallium phthalocyanine, metal-free phthalocyanine, chloroindium phthalocyanine and the like. Although these are known to have excellent sensitivity even when used alone, higher sensitivity can be realized by combining with an azo compound having an electron-withdrawing structure by the method of the present invention.

A phthalocyanine pigment coexists when the azo compound having a carboester group represented by the following general formula (I) is converted into an azo compound represented by the following general formula (a) by decarboxylation. A method for producing a composite phthalocyanine pigment will be described.

［但し式（Ｉ）中、Ａはアゾ化合物の残基であり、この残基Ａは、１つまたはそれ以上のヘテロ原子を介してｎ個のＥ基に結合しており、そしてこれらのヘテロ原子は、ＮおよびＯからなる群から選ばれ、残基Ａの一部を形成しており、Ｅ基は独立してＨ（水素原子）または次式で示されるカルボエステル基：−Ｃ（＝Ｏ）−Ｏ−Ｒ₁〔式中Ｒ₁は、炭素数４から１０の置換または非置換のアルキル基、アルケニル基、アルキニル基、シクロアルキル基、シクロアルケニル基、またはアラルキル基を表わす。〕を表わす。ただし、Ｅ基の全てが同時に水素原子であることはない。ｎは、１から９の整数である。］

[Wherein A is a residue of an azo compound, and this residue A is bonded to n E groups via one or more heteroatoms, and The atom is selected from the group consisting of N and O and forms part of the residue A, and the E group is independently H (hydrogen atom) or a carboester group represented by the following formula: —C (= O) —O—R ₁ [wherein R ₁ represents a substituted or unsubstituted alkyl group, alkenyl group, alkynyl group, cycloalkyl group, cycloalkenyl group, or aralkyl group having 4 to 10 carbon atoms. ]. However, not all E groups are hydrogen atoms at the same time. n is an integer from 1 to 9. ]

［但し式（ａ）中、Ａは一般式（Ｉ）と同義であり、Ｈは水素原子を表わし、ｎは、１から９の整数である。］

[In the formula (a), A is as defined in the general formula (I), H represents a hydrogen atom, and n is an integer of 1 to 9. ]

The decarboesterification of the azo compound is preferably carried out using any one of chemical means, thermal means and photolytic means.

The chemical means (chemical method) is a method of producing an azo pigment by a catalyst such as an acid or a base, but a preferred catalyst is an acid, and acetic acid, trifluoroacetic acid, propionic acid, acrylic acid, benzoic acid, hydrochloric acid. , Sulfuric acid, boric acid, p-toluenesulfonic acid. And salicylic acid.
The thermal means (thermal method) is a method for producing an azo pigment by heating to 50 ° C. to 300 ° C. in the presence of a solvent, but preferably from 70 ° C. to 250 ° C. under atmospheric pressure for 30 minutes. It is desirable to react for 20 hours.
The photolytic means (method) can be used if the azo compound represented by the general formula (1) has absorption light. Specifically, a high pressure or low pressure mercury lamp, a tungsten lamp, an LED lamp, a laser light source, or the like can be used.

Examples of the organic solvent used herein include ether solvents such as tetrahydrofuran and dioxane, glycol ether solvents such as ethylene glycol methyl ether and ethylene glycol ethyl ether, butanol, N, N-dimethylformamide, N, N- Examples include dimethylacetamide, ethyl cellosolve, ethyl acetate, butyl acetate, monochlorobenzene, dichlorobenzene, toluene, xylene, anisole, cyclohexanone, nitrobenzene, pyridine, picoline or quinoline.

By using a chemical method, a thermal method or a photolytic method in combination, an azo pigment can be produced more efficiently. In particular, a high-purity composite phthalocyanine pigment can be produced in good yield by combining a chemical method and a thermal method.

It is desirable that the other pigment coexisting with the azo compound represented by the general formula (I) is subjected to a fine treatment in advance. Preferably, a pigment having a particle size of 0.5 micron or less is used according to a mechanical pulverization method, a reprecipitation method, a fine particle formation method from a gas phase, or the like.
By adding and stirring these pigments to a solution in which the azo compound represented by the general formula (1) is dissolved in an organic solvent, the azo compound can be present at the molecular level in the pigment. The composite phthalocyanine pigment of the present invention can be produced by decarboesterification using chemical means, thermal means or photolytic means.

In the present invention, the azo compound represented by the general formula (1) is dissolved in an organic solvent, and the solution is adsorbed with silica gel, alumina, florisil, activated carbon, activated clay, diatomaceous earth, or perlite. It is also preferable to use it.
Examples of the organic solvent used here include ether solvents such as tetrahydrofuran or dioxane, glycol ether solvents such as ethylene glycol methyl ether and ethylene glycol ethyl ether, N, N-dimethylformamide, N, N-dimethylacetamide, Ethyl cellosolve, ethyl acetate, butyl acetate, dichloromethane, chloroform, carbon tetrachloride, dichloroethane, monochlorobenzene, dichlorobenzene, toluene, xylene, anisole, n-hexane, cyclohexane, cyclohexanone, nitrobenzene, pyridine, picoline or quinoline, etc. The mixed solvent is mentioned. Specific methods of the adsorption treatment include column chromatography, room temperature, or a method of adding an adsorbent during heating and filtering. Moreover, it can process more efficiently by combining with recrystallization.

Binder resins used in the charge generation layer include polyamide, polyurethane, epoxy resin, polyketone, polycarbonate, silicone resin, acrylic resin, polyvinyl butyral, polyvinyl formal, polyvinyl ketone, polystyrene, polysulfone, poly-N-vinylcarbazole, polyacrylamide. , Polyvinyl benzal, polyester, phenoxy resin, vinyl chloride-vinyl acetate copolymer, polyvinyl acetate, polyphenylene oxide, polyamide, polyvinyl pyridine, cellulose resin, casein, polyvinyl alcohol, polyvinyl pyrrolidone and the like. The amount of the binder resin is preferably 0 to 500 parts by mass and more preferably 10 to 300 parts by mass with respect to 100 parts by mass of the charge generation material.

In the composite phthalocyanine pigment of the present invention, since the periphery of the phthalocyanine pigment is covered with an azo pigment, the crystal stability of the phthalocyanine pigment is high, and the type and amount of the binder resin used in the coating solution for the charge generation layer are more flexible than before. Increased. That is, conventionally, in order to maintain the crystallinity of the phthalocyanine pigment, a certain amount or more of the binder resin is necessary. However, in the composite phthalocyanine pigment of the present invention, the necessary amount of the binder resin to maintain the crystal stability. Therefore, the charge accumulation, which has been caused by the presence of the binder resin, is suppressed, and the characteristics of the photoreceptor can be improved.

The charge generation layer disperses the charge generation material in a suitable solvent together with a binder resin as necessary using a known dispersion method such as a ball mill, an attritor, a sand mill, or an ultrasonic wave. Alternatively, it is formed by applying on an undercoat layer or an intermediate layer and drying. The binder resin may be added before or after the charge generating material is dispersed.

Examples of the solvent used for forming the charge generation layer include isopropanol, acetone, methyl ethyl ketone, cyclohexanone, tetrahydrofuran, dioxane, ethyl cellosolve, ethyl acetate, methyl acetate, dichloromethane, dichloroethane, monochlorobenzene, cyclohexane, toluene, xylene, ligroin. Although generally used organic solvents such as ketone solvents, ketone solvents, ester solvents, and ether solvents are particularly preferable. These may be used alone or in combination of two or more.

The coating solution for forming the charge generation layer is mainly composed of a charge generation material, a solvent and a binder resin, and includes any additive such as a sensitizer, a dispersant, a surfactant, and silicone oil. May be included.

As a method for coating the charge generation layer using the coating solution, known methods such as dip coating, spray coating, beat coating, nozzle coating, spinner coating, ring coating, and the like can be used.
The thickness of the charge generation layer is preferably from 0.01 to 5 μm, more preferably from 0.1 to 2 μm. After coating, it is heated and dried in an oven or the like. The drying temperature of the charge generation layer in the present invention is preferably from 50 ° C. to 160 ° C., more preferably from 80 ° C. to 140 ° C.

<Charge transport layer>
Next, the charge transport layer will be described.
The charge transport layer is formed by applying and drying a coating liquid in which a charge transport material and a binder resin are dissolved or dispersed in a solvent. Moreover, you may add additives, such as a plasticizer, a leveling agent, antioxidant, a lubricant, etc. individually or in 2 types or more to the coating liquid of a charge transport layer as needed.

Examples of charge transport materials include poly (N-vinylcarbazole) and derivatives thereof, poly (γ-carbazolylethyl glutamate) and derivatives thereof, pyrene-formaldehyde condensates and derivatives thereof, polyvinylpyrene, polyvinylphenanthrene, polysilane, and oxazole derivatives. Oxadiazole derivatives, imidazole derivatives, monoarylamine derivatives, diarylamine derivatives, triarylamine derivatives, stilbene derivatives, α-phenylstilbene derivatives, aminobiphenyl derivatives, benzidine derivatives, diarylmethane derivatives, triarylmethane derivatives, 9- Bistilbene derivatives such as styrylanthracene derivatives, pyrazoline derivatives, divinylbenzene derivatives, hydrazone derivatives, indene derivatives, butadiene derivatives, pyrene derivatives, etc. Materials, distyrylbenzene derivatives, enamine derivatives and the like. These charge transport materials may be used alone or in combination of two or more.
The content of the charge transport material is usually 20 to 300 parts by weight and preferably 40 to 150 parts by weight with respect to 100 parts by weight of the binder resin.

Binder resins include polystyrene, styrene-acrylonitrile copolymer, styrene-butadiene copolymer, styrene-maleic anhydride copolymer, polyester, polyvinyl chloride, vinyl chloride-vinyl acetate copolymer, polyvinyl acetate, poly Vinylidene chloride, polyarylate, phenoxy resin, polycarbonate, cellulose acetate resin, ethyl cellulose resin, polyvinyl butyral, polyvinyl formal, polyvinyl toluene, poly (N-vinylcarbazole), acrylic resin, silicone resin, epoxy resin, melamine resin, urethane resin, Examples thereof include thermoplastic or thermosetting resins such as phenol resins and alkyd resins.

Examples of the coating solvent include tetrahydrofuran, dioxane, toluene, cyclohexanone, methyl ethyl ketone, xylene, acetone, diethyl ether, and methyl ethyl ketone. Two or more kinds may be used in combination.
The film thickness of the charge transport layer is preferably 10 to 50 μm, more preferably 15 to 35 μm, from the viewpoint of resolution and responsiveness.

As a coating method, known methods such as a dip coating method, a spray coating method, a bead coating method, a nozzle coating method, a spinner coating method, and a ring coating method can be used, but the charge transport layer has a certain thickness. Since it is necessary to apply thickly, it is preferable to apply the dip coating method with a highly viscous liquid.
The charge transport layer after coating is dried by heating in an oven or the like. Although drying temperature changes also with the solvent contained in a coating liquid, it is preferable that it is 80-160 degreeC, and 110-140 degreeC is more preferable. The drying time is preferably 10 minutes or more, more preferably 20 minutes or more.

<Single layer>
Next, the case where the photosensitive layer has a single layer structure will be described.
This is a photoreceptor in which the above-described charge generation material and charge transport material are dispersed or dissolved in a binder resin to realize a charge generation function and a charge transport function in one layer.
In the photosensitive layer, a charge generating substance, a charge transporting substance and a binder resin are dissolved or dispersed in a solvent such as tetrahydrofuran, dioxane, dichloroethane, methyl ethyl ketone, cyclohexane, cyclohexanone, toluene, xylene, etc., and this is dip coating, spray coating, bead coating. It can be formed by coating using a conventionally known method such as ring coating.
The charge transport material preferably contains both a hole transport material and an electron transport material.
Moreover, a plasticizer, a leveling agent, antioxidant, etc. can also be added as needed.
Regarding the charge generating substance, charge transporting substance, binder resin, organic solvent and various additives used in the single photosensitive layer, any material contained in the above-described charge generating layer and charge transporting layer should be used. Is possible.
As the binder resin, in addition to the binder resin previously mentioned in the charge transport layer, the binder resin mentioned in the charge generation layer may be mixed and used. The amount of the charge generating material with respect to 100 parts by mass of the binder resin is preferably 5 to 40 parts by mass, and more preferably 10 to 30 parts by mass.
The amount of the charge transport material is preferably 0 to 190 parts by mass, and more preferably 50 to 150 parts by mass. Further, the film thickness of the photosensitive layer is preferably 5 to 40 μm, more preferably 10 to 30 μm.

<Underlayer>
In the photoreceptor of the present invention, an undercoat layer can be provided between the conductive support and the photosensitive layer.
In general, the undercoat layer is mainly composed of a resin. However, in consideration of applying a photosensitive layer using a solvent thereon, such a resin is a resin having high solvent resistance to a general organic solvent. Preferably there is. Examples of such resins include water-soluble resins such as polyvinyl alcohol, casein, and sodium polyacrylate, alcohol-soluble resins such as copolymer nylon and methoxymethylated nylon, polyurethane, melamine resins, phenol resins, alkyd-melamine resins, and isocyanates. And curable resins that form a three-dimensional network structure, such as epoxy resins.

Further, a fine powder pigment of a metal oxide such as titanium oxide, silica, alumina, zirconium oxide, tin oxide, or indium oxide may be added to the undercoat layer in order to prevent moire and reduce residual potential.
Moreover, it can form using a solvent and a coating method similarly to the above-mentioned charge generation layer and charge transport layer. Furthermore, a silane coupling agent, a titanium coupling agent, a chromium coupling agent, or the like can be used as the undercoat layer.

<Protective layer>
In the present invention, a protective layer can be provided on the outermost surface of the photoreceptor in order to improve wear resistance. As the protective layer, a polymer charge transport material type obtained by polymerizing a charge transport component and a binder component, a filler dispersion type containing a filler, a cured type cured, etc. are known. It can be used for any known protective layer.

<Image forming apparatus>
Next, the electrophotographic method and the image forming apparatus of the present invention will be described in detail with reference to the drawings.
FIG. 5 is a schematic view for explaining the electrophotographic process and the image forming apparatus of the present invention, and the following examples also belong to the category of the present invention.
As shown in FIG. 5, the photoconductor (1) has a drum shape, but may be a sheet or an endless belt. For charging charger (12), pre-transfer charger (15), transfer charger (18), separation charger (19), pre-cleaning charger (21), in addition to corotron, scorotron, solid state charger (solid state charger) A roller-shaped charging member or a brush-shaped charging member is used, and all known means can be used.

As the charging member, a non-contact charging method such as corona charging or a contact charging method using a charging member using a roller or a brush is generally used, and any of them can be used effectively in the present invention. In particular, the charging roller can significantly reduce the amount of ozone generated compared to corotron, scorotron, etc., and is effective in stability and prevention of image quality deterioration when the photoreceptor is used repeatedly.
However, due to the contact between the photoconductor and the charging roller, the charging roller is contaminated by repeated use, which affects the photoconductor and contributes to the occurrence of abnormal images and reduced wear resistance. It was.
In particular, when a photoconductor having high wear resistance is used, it is difficult to perform reface due to surface wear, and therefore it is necessary to reduce contamination of the charging roller.

Therefore, as shown in FIG. 6, the charging member (charging roller) (12) is provided with a gap forming member (12a) and is disposed close to the photosensitive member (1) through the gap, so that the pollutant is charged. It is difficult to adhere to the roller or it can be easily removed, and the influence thereof can be reduced. In this case, the gap between the photosensitive member and the charging roller is preferably small, for example, 100 μm or less is preferable, and 50 μm or less is more preferable.
However, by making the charging roller non-contact, discharge may become non-uniform and charging of the photoreceptor may become unstable. Such a problem is caused by maintaining the charging stability by superimposing the alternating current component on the direct current component, thereby making it possible to simultaneously reduce the influence of ozone, the charging roller contamination and the charging effect. .

On the other hand, light sources such as an image exposure unit (13) and a charge removal lamp (11) include fluorescent lamps, tungsten lamps, halogen lamps, mercury lamps, sodium lamps, light emitting diodes (LEDs), semiconductor lasers (LD), and electroluminescence (EL). ) And other luminescent materials can be used. Among these, a semiconductor laser (LD) and a light emitting diode (LED) are mainly used.
Various types of filters such as a sharp cut filter, a band pass filter, a near infrared cut filter, a dichroic filter, an interference filter, and a color temperature conversion filter can be used to irradiate only light in a desired wavelength range.

The light source or the like provides the photosensitive member (1) with light by providing a transfer step, a static elimination step, a cleaning step, or a pre-exposure step using light irradiation. However, the exposure of the photoreceptor (1) in the static elimination step has a large influence of fatigue on the photoreceptor (1), and may cause a decrease in charge and an increase in residual potential.
Therefore, there is a case where it is possible to eliminate static electricity by applying a reverse bias in the charging process or cleaning process instead of static elimination by exposure, which may be effective from the viewpoint of enhancing the durability of the photoreceptor.

When the electrophotographic photosensitive member (1) is positively (negatively) charged and image exposure is performed, a positive (negative) electrostatic latent image is formed on the surface of the photosensitive member. A positive image can be obtained by developing this with negative (positive) toner (electrodetection fine particles), and a negative image can be obtained by developing with positive (negative) toner.
A known method is applied to the developing unit, and a known method is also used for the charge eliminating unit.

As the transfer means, the above-described charger can be generally used. However, as shown in FIG. 5, a combination of the transfer charger (18) and the separation charger (19) is effective.
Further, the toner image is directly transferred from the photosensitive member to the paper using such a transfer unit. In the present invention, the toner image on the photosensitive member is once transferred to the intermediate transfer member, and then from the intermediate transfer member to the paper. An intermediate transfer method for transferring the toner to the photoconductor is more preferable for enhancing the durability or improving the image quality of the photoreceptor.

Among the contaminants that adhere to the surface of the photoconductor, discharge substances generated by charging and external additives contained in the toner are easy to pick up the effects of humidity and cause abnormal images. Paper powder is one of the causative substances, and when they adhere to the photoreceptor, abnormal images are more likely to occur, as well as a tendency to reduce wear resistance and cause uneven wear. Is seen. Therefore, it is more preferable from the viewpoint of high image quality that the photoconductor and the paper are not in direct contact for the above reason.

The intermediate transfer method is particularly effective for image forming apparatuses capable of full-color printing, and controls the prevention of color misregistration by forming a plurality of toner images on the intermediate transfer member and then transferring them to the paper at once. It is easy and effective for high image quality.
However, the intermediate transfer method requires four scans to obtain one full-color image, so that the durability of the photoconductor has been a big problem.
The photoconductor of the present invention is particularly effective and useful since it is easy to use in combination with an intermediate transfer type image forming apparatus because image blurring hardly occurs even without a drum heater.
The intermediate transfer member includes various materials or shapes such as a drum shape and a belt shape. In the present invention, any conventionally known intermediate transfer member can be used. It is effective and useful for achieving high quality or high image quality.

The toner developed on the photosensitive member (1) by the developing unit (14) is transferred to the transfer paper (17), but not all is transferred, and toner remaining on the photosensitive member 1 is also generated. . Such toner is removed from the photoreceptor (1) by the fur brush (22) or the cleaning blade (23).
This cleaning process may be performed only with a cleaning brush or may be performed in combination with a blade, and known cleaning brushes such as a fur brush and a mag fur brush are used.

As described above, the cleaning is a process of removing toner remaining on the photosensitive member (1) after the transfer. However, the photosensitive member (1) is repeatedly rubbed by the blade (23) or the brush (22). As a result, wear of the photoconductor (1) is promoted or an abnormal image may be generated due to scratches.
In addition, if the surface of the photoconductor is contaminated due to poor cleaning, it not only causes an abnormal image, but also significantly reduces the life of the photoconductor. In particular, in the case of a photoreceptor having a layer containing a filler for improving wear resistance on the outermost surface, contaminants attached to the surface of the photoreceptor are difficult to remove. It will promote the occurrence of. Therefore, improving the cleaning property of the photoconductor is very effective for improving the durability and image quality of the photoconductor.

As means for improving the cleaning property of the photosensitive member, a method of reducing the coefficient of friction on the surface of the photosensitive member is known. Methods for reducing the coefficient of friction on the surface of the photoreceptor are classified into a method in which various lubricants are contained in the photoreceptor surface and a method in which the lubricant is supplied to the photoreceptor surface from the outside. The former is advantageous for small-diameter photoreceptors because of the high degree of freedom in layout around the engine, but the coefficient of friction increases remarkably with repeated use, and there remains a problem in its sustainability. On the other hand, the latter needs to be provided with a component for supplying a lubricating substance, but is effective for enhancing the durability of the photoreceptor because of high stability of the friction coefficient. Among them, the method of adhering to the photoreceptor during development by incorporating a lubricant into the developer is not restricted by the layout around the engine, and the effect of reducing the friction coefficient on the photoreceptor surface is high. Therefore, it is a very effective means for improving the durability and image quality of the photoreceptor.

These lubricants include lubricating fluids such as silicone oil and fluorine oil, various fluorine-containing resins such as PTFE, PFA and PVDF, silicone resins, polyolefin resins, silicone grease, fluorine grease, paraffin wax, fatty acid esters , Fatty acid metal salts such as zinc stearate, lubricating liquids such as graphite and molybdenum disulfide, solids, powders, and the like, but particularly when mixed with a developer, it must be in the form of a powder, especially stearic acid Zinc has little adverse effect and can be used very effectively. When the zinc stearate powder is contained in the toner, it is necessary to consider the balance and the influence on the toner, and the content is preferably 0.01 to 0.5% by mass with respect to the toner. 3 mass% is more preferable.

The photoconductor according to the present invention can be applied to a small-diameter photoconductor because high photosensitivity and high stability are realized. Therefore, as an image forming apparatus or method for using the above photoreceptor more effectively, each developing unit corresponding to a plurality of colors of toner is provided with a plurality of corresponding photoreceptors, thereby performing parallel processing. It is very effectively used in a so-called tandem type image forming apparatus. The tandem image forming apparatus includes at least four color toners of yellow (C), magenta (M), cyan (C), and black (K) required for full-color printing and a developing unit that holds them. Further, by providing at least four photoconductors corresponding to them, full-color printing can be performed at an extremely high speed as compared with a conventional image forming apparatus capable of full-color printing.

FIG. 7 is a schematic diagram for explaining the tandem-type full-color electrophotographic apparatus of the present invention, and the following modifications also belong to the category of the present invention.
In FIG. 7, photoconductors (1C (cyan)), (1M (magenta)), (1Y (yellow)), and (1K (black)) are drum-like photoconductors (1), and these photoconductors. (1C, 1M, 1Y, 1K) rotate in the direction of the arrows in the figure, and at least around them, charging members (12C, 12M, 12Y, 12K), developing members (14C, 14M, 14Y, 14K), Cleaning members (15C, 15M, 15Y, 15K) are arranged. The charging members (12C, 12M, 12Y, 12K) constitute a charging device (12) for uniformly charging the surface of the photoreceptor (1).

From the back side of the photoreceptor (1) between the charging member (12C, 12M, 12Y, 12K) and the developing member (14C, 14M, 14Y, 14K), laser light (13C, 13M, 13Y, 13K) and an electrostatic latent image is formed on the photoconductors (1C, 1M, 1Y, 1K).
Then, four image forming elements (10C, 10M, 10Y, 10K) centering on such a photoreceptor (1C, 1M, 1Y, 1K) are along a transfer conveyance belt (25) which is a transfer material conveyance means. Are juxtaposed.
The transfer conveyance belt (25) is disposed between the developing member (14C, 14M, 14Y, 14K) of each image forming unit (10C, 10M, 10Y, 10K) and the cleaning member (15C, 15M, 15Y, 15K). A transfer brush (26C) for applying a transfer bias to a surface (back surface) which is in contact with the photoconductors (1C, 1M, 1Y, 1K) and contacts the back side of the photoconductor (1) side of the transfer conveyance belt (25). , 26M, 26Y, and 26K). Each image forming element (10C, 10M, 10Y, 10K) is different in the color of the toner inside the developing device, and the others are the same in configuration.

In the color electrophotographic apparatus having the configuration shown in FIG. 7, the image forming operation is performed as follows. First, in each image forming element (10C, 10M, 10Y, 10K), the charging member (12C, 12M) in which the photosensitive member (1C, 1M, 1Y, 1K) rotates in the direction of the arrow (the direction along with the photosensitive member 1). , 12Y, 12K), and then, by the laser beam (13C, 13M, 13Y, 13K), an image of each color to be created by an exposure unit (not shown) arranged outside the photoreceptor (1). A corresponding electrostatic latent image is formed.

Next, the latent image is developed by a developing member (14C, 14M, 14Y, 14K) to form a toner image. The developing members (14C, 14M, 14Y, and 14K) are developing members that perform development with toners of C (cyan), M (magenta), Y (yellow), and K (black), respectively. 1M, 1Y, and 1K) are overlaid on the transfer paper.

The transfer paper (17) is fed out from the tray by the paper feed roller (24), and is temporarily stopped by the pair of registration rollers (16). The transfer paper (17) is transferred to the transfer conveyance belt (25) in synchronization with the image formation on the photoconductor. Sent. The transfer paper (17) held on the transfer / conveying belt (25) is transported, and toner images of each color are transferred at contact positions (transfer portions) with the respective photosensitive members (1C, 1M, 1Y, 1K). It is.

The toner image on the photosensitive member is transferred to the transfer paper (by the electric field formed by the potential difference between the transfer bias applied to the transfer brush (26C, 26M, 26Y, 26K) and the photosensitive member (1C, 1M, 1Y, 1K). 17) Transferred on top.
Then, the recording paper (17) on which the four color toner images are passed through the four transfer portions is conveyed to the fixing device (27), where the toner is fixed, and is discharged to a paper discharge portion (not shown). The
In addition, the residual toner remaining on the photosensitive members (1C, 1M, 1Y, 1K) without being transferred by the transfer unit is collected by a cleaning device (15C, 15M, 15Y, 15K).

In the example of FIG. 7, the image forming elements are arranged in the order of C (cyan), M (magenta), Y (yellow), and K (black) from the upstream side to the downstream side in the transfer paper conveyance direction. However, it is not limited to this order, and the color order is arbitrarily set. Further, when a black-only document is created, it is particularly effective to use the present invention to provide a mechanism that stops the image forming elements (10C, 10M, 10Y) other than black.
Further, although the charging member is in contact with the photosensitive member in FIG. 7, by using a charging mechanism as shown in FIG. 6, an appropriate gap (about 10 to 200 μm) is provided between them. In addition, the wear amount of the both can be reduced, and toner filming on the charging member can be reduced and the toner can be used well.

The image forming means as described above may be fixedly incorporated in a copying apparatus, a facsimile, or a printer, but may be incorporated in these apparatuses in the form of a process cartridge.

As shown in FIG. 8, the process cartridge includes a photoconductor (1), in addition to a charging means (12), an exposure means (13), a developing means (14), a transfer means (18), and a cleaning means. (23) and one device (part) including the static elimination means.

The above-described tandem image forming apparatus can transfer a plurality of toner images at a time, so that high-speed full-color printing is realized.
However, since at least four photoconductors are required, an increase in the size of the apparatus is unavoidable, and depending on the amount of toner used, there is a difference in the wear amount of each photoconductor, thereby reproducing the color. There are many problems such as a decrease in performance and occurrence of abnormal images.
On the other hand, the photosensitive member according to the present invention can be applied to a small-diameter photosensitive member by realizing high photosensitivity and high stability, and the influence of increase in residual potential, sensitivity deterioration, etc. is reduced. Even if the amount of the photoconductor used is different, the difference in residual potential and sensitivity over time is small, and a full color image having excellent color reproducibility can be obtained even when used repeatedly for a long time.

Examples of the present invention will be described below, but the present invention is not limited to the following examples.

<Synthesis of titanyl phthalocyanine pigment used in the present invention>
(Synthesis Example 1)
A pigment was prepared in accordance with JP 2004-83859 A and Example 1. That is, 292 parts of 1,3-diiminoisoindoline and 1800 parts of sulfolane are mixed, and 204 parts of titanium tetrabutoxide are added dropwise under a nitrogen stream. After completion of the dropwise addition, the temperature was gradually raised to 180 ° C., and the reaction was carried out by stirring for 5 hours while maintaining the reaction temperature between 170 ° C. and 180 ° C. After the reaction is complete, the mixture is allowed to cool, and then the precipitate is filtered, washed with chloroform until the powder turns blue, then washed several times with methanol, then washed several times with hot water at 80 ° C. and dried. Crude titanyl phthalocyanine was obtained.
60 parts of the obtained crude titanyl phthalocyanine pigment washed with hot water was stirred and dissolved in 1000 parts of 96% sulfuric acid at 3 to 5 ° C. and filtered. The obtained sulfuric acid solution was added dropwise to 35000 parts of ice water with stirring, the precipitated crystals were filtered, and then washed with water until the washing solution became medieval to obtain an aqueous paste of titanyl phthalocyanine pigment.
Add 1500 parts of tetrahydrofuran to this water paste and stir vigorously (2000 rpm) with a homomixer (Kennis, MARK, model f) at room temperature. When the paste color changes from dark blue to light blue (about 20 after the start of stirring). Min), stirring was stopped, and vacuum filtration was performed immediately. The crystals obtained on the filtration device were washed with tetrahydrofuran to obtain 98 parts of a pigment wet cake. This was dried under reduced pressure (5 mmHg) at 70 ° C. for 2 days to obtain 78 parts of a titanyl phthalocyanine pigment.

The obtained titanyl phthalocyanine powder was subjected to X-ray diffraction spectrum measurement under the following conditions. As a result, the Bragg angle 2θ with respect to the Cu—Kα ray (wavelength 1.542 mm) was 27.2 ± 0.2 °, and the maximum peak and minimum angle 7 Has a peak at .3 ± 0.2 °, and further has major peaks at 9.4 ± 0.2 °, 9.6 ± 0.2 °, 24.0 ± 0.2 °, and 7 A titanyl phthalocyanine powder having no peak between the peak at 3 ° and the peak at 9.4 ° and further having no peak at 26.3 ° was obtained. The results are shown in the figure.
<X-ray diffraction spectrum measurement conditions>
X-ray tube: Cu
Voltage: 50kV
Current: 30mA
Scanning speed: 2 ° / min Scanning range: 3 ° -40 °
Time constant: 2 seconds

<Composite phthalocyanine pigment 1>
Among the compounds in which the main skeleton of the azo compound is the general formula (12), an azo compound having a carboester group represented by the structural formula (12-3) is synthesized as follows, and this is used as described below. A mixed solution with a titanyl phthalocyanine pigment was prepared, and decarboesterification treatment was performed using both chemical means and thermal means to produce a composite phthalocyanine pigment.

[Synthesis of Azo Compound Having Carboester Group Represented by Structural Formula (12-3)]
A precursor of an azo compound having a carboester group represented by the structural formula (12-3) [all the E groups in the structural formula (12-3) are H (hydrogen atoms)] 0.83 grams, 2.6 grams (12 moles) of pyrocarboxylic acid di-tert-butyl ester was dispersed in 150 ml of dehydrated pyridine, stirred for 15 minutes at room temperature, further heated to about 50 ° C., and reacted for 30 minutes. Gradually reddish and a homogeneous solution was obtained. The temperature was returned to room temperature, the solvent was removed, and about 50 ml of ethyl acetate was added to obtain 1.18 grams (yield: 95.3%) of a red powder. This was further purified by column chromatogram (silica gel / chloroform).
The results of elemental analysis of the obtained product are shown in Table 1 below. In addition, the calculated value (%) of each element in the following Table 1 assumes that all the carboester groups (E groups) whose products are represented by the structural formula (12-3) are C ₅ H ₉ O _2. The chemical formula of the azo compound is calculated as C ₆₇ H ₆₀ N ₆ O ₁₃ Cl ₂ .

また、上記生成物の赤外線吸収スペクトル（ＫＢｒ錠剤法）による分析の結果、置換基に由来する吸収、すなわち、２９８０ｃｍ^−１に飽和炭化水素に基づく吸収、１７６０ｃｍ^−１にカルボネートのＣ＝Ｏ伸縮振動に基づく吸収が認められた。

As a result of analysis by infrared absorption spectrum (KBr tablet method) of the product, absorption derived from a substituent, i.e., absorption based on saturated hydrocarbons 2980cm ^-1, C = O stretching vibration of carbonate to 1760 cm ^-1 Absorption based on was observed.

[Azo Pigment [Production of Composite Phthalocyanine Pigment Consisting of All E Groups in Structural Formula (12-3) are H (Hydrogen Atom)] and Titanyl Phthalocyanine Pigment]
0.98 g of the azo compound (12-3) [E: C ₅ H ₉ O ₂ ] obtained above was heated with stirring in 100 ml of toluene to obtain a dark reddish brown solution. After 0.46 grams of titanyl phthalocyanine pigment was added to this solution, 0.9 grams of trifluoroacetic acid and 0.5 grams of water were further added and reacted at 80 ° C. for 9 hours with vigorous stirring. After confirming the disappearance of the azo compound (12-3) by thin layer chromatography, the temperature was returned to room temperature, filtered through a 0.1 μm fluoropore, washed twice with 100 ml of methanol, and dark blue powder (1.05 g) Got.
As a result of analysis by infrared absorption spectrum (KBr tablet method) of the obtained powder, absorption derived from a substituent recognized in the azo compound (12-3), that is, absorption based on a saturated hydrocarbon of 2980 cm ⁻¹ , 1760 cm It was confirmed that absorption based on C═O stretching vibration of carbonate of ⁻¹ disappeared.

<Composite phthalocyanine pigment 2>
Among the compounds in which the main skeleton of the azo compound is the general formula (12), an azo compound having a carboester group represented by the structural formula (12-2) is synthesized as follows, and this is used as described below. A mixed solution with a titanyl phthalocyanine pigment was prepared, and decarboesterification treatment was performed using both chemical means and thermal means to produce a composite phthalocyanine pigment.

[Synthesis of Azo Compound Having Carboester Group Represented by Structural Formula (12-2)]
1.61 grams of a precursor of an azo compound having a carboester group represented by the structural formula (12-2) [all E groups in the structural formula (12-2) are H (hydrogen atoms)], Disperse 4.3 g (10 moles) of pyrocarboxylic acid di-tert-butyl ester in 50 ml of dehydrated pyridine and 200 ml of dehydrated N, N-dimethylformamide, stir at room temperature for 15 minutes, and then warm to about 50 ° C. The reaction was performed for 2 hours. Gradually reddish and a homogeneous solution was obtained. After returning to room temperature, the solvent was removed, and about 100 ml of ethyl acetate was added to obtain 2.24 grams (yield: 93%) of a red powder.
The results of elemental analysis of the obtained powder are shown in Table 2 below. In addition, the calculated value (%) of each element in the following Table 2 assumes that all carboester groups (E groups) represented by the structural formula (12-2) are C ₅ H ₉ O _2. The chemical formula of the azo compound is calculated as C ₆₈ H ₆₃ N ₆ O ₁₃ Cl.

また、上記生成物の赤外線吸収スペクトル（ＫＢｒ錠剤法）による分析の結果、置換基に由来する吸収、すなわち、２９８０ｃｍ^−１に飽和炭化水素に基づく吸収、１７６０ｃｍ^−１にカルボネートのＣ＝Ｏ伸縮振動に基づく吸収が認められた。

As a result of analysis by infrared absorption spectrum (KBr tablet method) of the product, absorption derived from a substituent, i.e., absorption based on saturated hydrocarbons 2980cm ^-1, C = O stretching vibration of carbonate to 1760 cm ^-1 Absorption based on was observed.

[Azo Pigment [Production of Composite Phthalocyanine Pigment Consisting of All E Groups in Structural Formula (12-2) are H (Hydrogen Atom)] and Titanyl Phthalocyanine Pigment]
0.97 g of the azo compound (12-2) [E: C ₅ H ₉ O ₂ ] obtained above was heated with stirring in 100 ml of toluene to obtain a dark reddish brown solution. After adding 0.46 g of titanyl phthalocyanine pigment to this solution, 1.8 g of trifluoroacetic acid and 1.0 g of water were further added and reacted at 80 ° C. for 9 hours with vigorous stirring. After confirming the disappearance of the azo compound (12-2) by thin layer chromatography, the solution was returned to room temperature, filtered through a 0.1 μm fluoropore, washed twice with 100 ml of methanol, and a dark blue powder (1.04 g) )
As a result of analysis by infrared absorption spectrum (KBr tablet method) of the obtained powder, absorption derived from a substituent recognized in the azo compound (12-2), that is, absorption based on a saturated hydrocarbon of 2980 cm ⁻¹ , 1760 cm It was confirmed that absorption based on C═O stretching vibration of carbonate of ⁻¹ disappeared.

<Composite phthalocyanine pigment 3>
Among the compounds in which the main skeleton of the azo compound is the general formula (14), an azo compound having a carboester group represented by the structural formula (14-5) is synthesized as follows, and this is used as described below. A mixed solution with a titanyl phthalocyanine pigment was prepared and subjected to decarboesterification treatment to produce a composite phthalocyanine pigment.

[Synthesis of an azo compound having a carboester group represented by the structural formula (14-5)]
0.81 grams of a precursor of an azo compound having a carboester group represented by the structural formula (14-5) [all E groups in the structural formula (14-5) are H (hydrogen atoms)], 2.7 grams (12 moles) of pyrocarboxylic acid di-tert-amyl ester was dispersed in 150 ml of dehydrated pyridine, stirred at room temperature for 15 minutes, further heated to about 50 ° C., and reacted for 2 hours. Gradually reddish and a homogeneous solution was obtained. The temperature was returned to room temperature, the solvent was removed, and about 50 ml of ethyl acetate was added to obtain 1.1 grams (yield: 86.6%) of a red powder.
The results of elemental analysis of the obtained product are shown in Table 3 below. In addition, the calculated value (%) of each element in the following Table 3 assumes that all carboester groups (E groups) whose products are represented by the structural formula (14-5) are C ₆ H ₁₁ O _2. The chemical formula of the azo compound is calculated as C ₇₅ H ₇₂ N ₆ O ₁₃ .

また、上記生成物の赤外線吸収スペクトル（ＫＢｒ錠剤法）による分析の結果、置換基に由来する吸収、すなわち、２９８０ｃｍ^−１に飽和炭化水素に基づく吸収、１７６０ｃｍ^−１にカルボネートのＣ＝Ｏ伸縮振動に基づく吸収が認められた。

As a result of analysis by infrared absorption spectrum (KBr tablet method) of the product, absorption derived from a substituent, i.e., absorption based on saturated hydrocarbons 2980cm ^-1, C = O stretching vibration of carbonate to 1760 cm ^-1 Absorption based on was observed.

[Azo Pigment [Production of Composite Phthalocyanine Pigment Consisting of All E Groups in Structural Formula (14-5) are H (Hydrogen Atom)] and Titanyl Phthalocyanine Pigment]
The azo compound (14-5) [E: C ₆ H ₁₁ O ₂ ] 1.01 gram obtained above was heated with stirring in 100 ml of 2-butanone to obtain a dark reddish brown solution. After adding 0.92 grams of titanyl phthalocyanine pigment to this solution, 18.2 grams of trifluoroacetic acid, 10 grams of acetic acid and 0.5 grams of water were further added and reacted at 80 ° C. for 6 hours with vigorous stirring. After confirming the disappearance of the azo compound by thin layer chromatography, the temperature was returned to room temperature, filtered through a 0.1 μm fluoropore, and washed twice with 100 ml of methanol to obtain a dark blue powder (1.45 g).
Analysis by infrared absorption spectrum of the resulting powder (KBr tablet method), absorption derived from substituents observed in azo compound, i.e., absorption based on a saturated hydrocarbon of 2980cm ^-1, a carbonate of 1760 cm ^-1 It was confirmed that absorption based on C = O stretching vibration disappeared.

<Composite phthalocyanine pigment 4>
Among the compounds in which the main skeleton of the azo compound is the general formula (13), an azo compound having a carboester group represented by the structural formula (13-1) is synthesized as follows, and this is used as described below. A mixed solution with titanyl phthalocyanine was prepared and subjected to decarboesterification treatment to produce a composite phthalocyanine pigment.

[Synthesis of Azo Compound Having Carboester Group Represented by Structural Formula (13-1)]
0.94 grams of a precursor of an azo compound having a carboester group represented by the structural formula (13-1) [all E groups in the structural formula (13-1) are H (hydrogen atoms)] Pyrocarboxylic acid di-tert-butyl ester (2.6 g, 12 moles) was dispersed in 150 ml of dehydrated pyridine, stirred at room temperature for 15 minutes, further heated to about 50 ° C., and reacted for 2 hours. Gradually reddish and a homogeneous solution was obtained. The temperature was returned to room temperature, the solvent was removed, and about 50 ml of ethyl acetate was added to obtain 1.11 grams (yield: 83.2%) of a red powder.
The results of elemental analysis of the obtained product are shown in Table 4 below. In addition, the calculated value (%) of each element in the following Table 4 assumes that all the carboester groups (E groups) whose products are represented by the structural formula (13-1) are C ₅ H ₉ O _2. The chemical formula of the azo compound is calculated as C ₆₈ H ₆₀ N ₆ O ₁₄ Br ₂ .

また、上記生成物の赤外線吸収スペクトル（ＫＢｒ錠剤法）による分析の結果、置換基に由来する吸収、すなわち、２９８０ｃｍ^−１に飽和炭化水素に基づく吸収、１７６０ｃｍ^−１にカルボネートのＣ＝Ｏ伸縮振動に基づく吸収が認められた。

As a result of analysis by infrared absorption spectrum (KBr tablet method) of the product, absorption derived from a substituent, i.e., absorption based on saturated hydrocarbons 2980cm ^-1, C = O stretching vibration of carbonate to 1760 cm ^-1 Absorption based on was observed.

[Azo Pigment [Production of Composite Phthalocyanine Pigment Consisting of All E Groups in Structural Formula (13-1) are H (Hydrogen Atom)] and Titanyl Phthalocyanine Pigment]
Azo compound obtained in the above (13-1) [E: C ₅ H ₉ O _2] 0.34 g and N, warmed while stirring in N- dimethylformamide 100 ml, and a solution of deep red-brown. After adding 3.1 g of titanyl phthalocyanine pigment to this solution, 5.2 g of paratoluenesulfonic acid was further added and reacted at 150 ° C. for 9 hours with vigorous stirring. After confirming the disappearance of the azo compound by thin layer chromatography, the solution was returned to room temperature, filtered through a 0.1 μm fluoropore, and washed twice with 100 ml of 2-butanone to obtain a dark blue powder (3.2 grams). .
Analysis by infrared absorption spectrum of the resulting powder (KBr tablet method), absorption derived from substituents observed in azo compound, i.e., absorption based on a saturated hydrocarbon of 2980cm ^-1, a carbonate of 1760 cm ^-1 It was confirmed that absorption based on C = O stretching vibration disappeared.

In an aluminum cylinder having a diameter of 30 mm and a length of 340 mm as a conductive support, an undercoat layer coating solution, a charge generation layer coating solution, and a charge transport layer coating solution having the following composition are sequentially applied by dip coating. The substrate was dried to form an undercoat layer of about 3.5 μm, a charge generation layer, and a charge transport layer of about 28 μm, and a laminated photoreceptor was produced. The thickness of the charge generation layer was adjusted so that the transmittance of the charge generation layer at 780 nm was 20%. The transmittance of the charge generation layer is obtained by applying a charge generation layer coating solution of the following composition to an aluminum cylinder wrapped with a polyethylene terephthalate film under the same conditions as the production of the photoreceptor, and the polyethylene without the charge generation layer applied Using the terephthalate film as a comparative control, the transmittance at 780 nm was evaluated with a commercially available spectrophotometer (Shimadzu: UV-3100). The charge generation layer coating solution used was a solution that was circulated and stored for about one month after being dispersed by a bead mill. In addition, after coating each layer, drying by touch is performed, and then the undercoat layer is dried at 130 ° C. for 20 minutes, the charge generation layer is dried at 150 ° C. for 20 minutes, and the charge transport layer is dried at 120 ° C. for 20 minutes. Body 1 was obtained.

(Coating liquid for undercoat layer)
Titanium oxide CR-EL (manufactured by Ishihara Sangyo Co., Ltd.) 50 parts Alkyd resin Beckolite M6401-50 14 parts (solid content 50 wt%, manufactured by Dainippon Ink & Chemicals, Inc.)
Melamine resin L-145-60 8 parts (solid content 60% by weight, manufactured by Dainippon Ink & Chemicals, Inc.)
2-butanone 120 parts

(Coating solution for charge generation layer)
Composite phthalocyanine pigment 1 10 parts Polyvinyl butyral resin BX-1 (Sekisui Chemical) 10 parts MEK 600 parts

(Coating liquid for charge transport layer)
Bisphenol Z polycarbonate 10 parts (Panlite TS-2050, manufactured by Teijin Chemicals)
Charge transport material of the following structural formula (17) 7 parts Tetrahydrofuran 80 parts 1% silicone oil tetrahydrofuran solution 0.2 part (KF50-1CS, manufactured by Shin-Etsu Chemical Co., Ltd.)

An electrophotographic photoreceptor 2 was obtained in the same manner as in Example 1 except that the composite phthalocyanine pigment 1 in the charge generation layer coating solution was changed to a composite phthalocyanine pigment 2 in Example 1.

In Example 1, an electrophotographic photosensitive member 3 was prepared in the same manner as in Example 1 except that the charge generation layer coating solution was changed as follows.
(Coating solution for charge generation layer)
Composite phthalocyanine pigment 1 10 parts Polyvinyl butyral resin BX-1 (Sekisui Chemical) 2 parts MEK 360 parts

An electrophotographic photoreceptor 4 was obtained in the same manner as in Example 1 except that the composite phthalocyanine pigment 1 in the charge generation layer coating solution was changed to the composite phthalocyanine pigment 3 in Example 1.

An electrophotographic photoreceptor 5 was obtained in the same manner as in Example 1 except that the composite phthalocyanine pigment 1 in the charge generation layer coating solution was changed to the composite phthalocyanine pigment 4 in Example 1.

<Comparative Example 1>
In Example 1, an electrophotographic photoreceptor 6 was obtained in the same manner as in Example 1 except that the composite phthalocyanine pigment 1 used in the coating solution for charge generation layer was changed to the titanyl phthalocyanine pigment obtained in Synthesis Example 1. .

<Comparative example 2>
In Example 3, an electrophotographic photoreceptor 7 was obtained in the same manner as in Example 1 except that the composite phthalocyanine pigment 1 used in the coating solution for the charge generation layer was changed to the titanyl phthalocyanine pigment obtained in Synthesis Example 1. .

<Comparative Example 3>
In Example 1, an electrophotographic photosensitive member 8 was prepared in the same manner as in Example 1 except that the charge generation layer coating solution was changed as follows.
(Coating solution for charge generation layer)
Titanyl phthalocyanine pigment obtained from Synthesis Example 1 5 parts azo pigment (12) -3 (E = H: but not decarboesterified) 5 parts polyvinyl butyral resin BX-1 (Sekisui Chemical) 10 parts MEK 600 copies

<Comparative example 4>
In Example 1, an electrophotographic photoreceptor 9 was prepared in the same manner as in Example 1 except that the charge generation layer coating solution was changed as follows.
(Coating solution for charge generation layer)
Titanyl phthalocyanine pigment obtained from Synthesis Example 1 5 parts azo pigment (12-2) (E = H: but not decarboesterified) 5 parts polyvinyl butyral resin BX-1 (Sekisui Chemical) 10 parts MEK 600 copies

<Comparative Example 5>
In Example 1, an electrophotographic photosensitive member 10 was produced in the same manner as in Example 1 except that the charge generation layer coating solution was changed as follows.
(Coating solution for charge generation layer)
Titanyl phthalocyanine pigment obtained from Synthesis Example 1 5 parts azo pigment (14) -5 (E = H: but not decarboesterified) 5 parts polyvinyl butyral resin BX-1 (Sekisui Chemical Co., Ltd.) 10 parts MEK 600 copies

<Comparative Example 6>
In Example 1, an electrophotographic photoreceptor 11 was prepared in the same manner as in Example 1 except that the charge generation layer coating solution was changed as follows.
(Coating solution for charge generation layer)
Titanyl phthalocyanine pigment obtained from Synthesis Example 1 5 parts azo pigment (13) -1 (E = H: not decarboesterified) 5 parts polyvinyl butyral resin BX-1 (Sekisui Chemical Co., Ltd.) 10 parts MEK 600 copies

<Evaluation of crystal stability of coating solution for charge generation layer>
With the formulation of each example, after preparing a dispersion with a ball mill, it was circulated and stored for 30 days. The solution was sampled and X-ray diffraction measurement was performed before coating the photoreceptor. The measurement was performed under the following conditions using RINT-1100: Rigaku Denki.
X-ray tube Cu Voltage: 40 kV
Current: 20mA
Scanning speed: 1 ° / min Scanning range: 3 ° -40 °

The measurement was performed immediately after preparation of the composite phthalocyanine pigment or phthalocyanine pigment before preparation of the dispersion and the coating solution for the charge generation layer, and after circulation storage for 30 days. With respect to the crystal form of titanyl phthalocyanine, the crystal stability was evaluated from the peak intensities where the Bragg angle 2θ of the X-ray spectrum was 26.2 ± 0.2 ° and 27.2 ± 0.2 °.

実施例３と実施例１のピーク強度の差は、比較例２と比較例１のピーク強度の差よりも小さいことから、本発明における複合フタロシアニン顔料は、塗工液中のバインダー樹脂が少なくても結晶転移が生じず、安定であることが分かる。

Since the difference in peak intensity between Example 3 and Example 1 is smaller than the difference in peak intensity between Comparative Example 2 and Comparative Example 1, the composite phthalocyanine pigment in the present invention has less binder resin in the coating liquid. It can be seen that no crystal transition occurs and is stable.

<Evaluation of actual machine>
For paper running with an actual machine, the electrophotographic photosensitive member is mounted on an electrophotographic process cartridge, and the bright part potential measurement is performed in a high temperature / high humidity, low temperature / low humidity environment, and normal temperature / humidity environment using a modified Ricoh imgio Neo271 machine. Was performed by the following method after the initial and 300,000 actual paper feeding tests (A4, MyPaper made by NBS Ricoh, starting charging potential -800 V).
After storing the photoconductor in a high-temperature and high-humidity environment (temperature 30 ° C., humidity 90%) or in a normal temperature and normal humidity environment (temperature 23 ° C., humidity 55%) for 24 hours, the light potential (VL ) Was measured. The measuring method is that the developing unit is disassembled, and an electrometer probe connected to the surface electrometer is attached to the developing unit at a position 50 mm from the upper end of the photosensitive member, and the photosensitive member is set on the developing unit. After adjusting the grid potential to be V), the bright portion potential was measured by outputting a solid black image. A TREK MODEL 344 was used as the surface electrometer.

In addition, after the actual paper passing test of 300,000 sheets, the photoconductor was removed, and a gas exposure test was performed in a dark place under a mixed gas atmosphere of nitrogen monoxide (NO) 40 ppm and nitrogen dioxide (NO ₂ ) 10 ppm for 2 days. Immediately after that, it was mounted again on the above-described image forming apparatus and the image was output to evaluate the image quality.

○: Level at which there is almost no degradation in image quality Δ: Level at which degradation in image quality can be seen even by visual observation ×: Level at which there is a serious problem in image quality

DESCRIPTION OF SYMBOLS 1 Photoconductor 1C, 1M, 1Y, 1K Photoconductor 2 Conductive support 3 Charge generation layer 4 Charge transport layer 5 Protective layer 6 Undercoat layer 7 Single layer type photosensitive layer 10C, 10M, 10Y, 10K Image forming element 11 Static elimination Lamp 12 Charging charger 12C, 12M, 12Y, 12K Charging member 13 Image exposure unit 13C, 13M, 13Y, 13K Laser light 14 Developing unit 14C, 14M, 14Y, 14K Developing member 15 Pre-transfer charger 15C, 15M, 15Y, 15K Cleaning Member 16 Registration roller 17 Transfer paper 18 Transfer charger 19 Separation charger 20 Separation claw 21 Charger before cleaning 22 Fur brush 23 Cleaning blade 24 Paper feed roller 25 Transfer conveyance belts 26C, 26M, 26Y, 26K Transfer brush 27 Fixing device

JP 47-37543 A JP 52-55643 A JP-A-52-8832 JP 58-222152 A JP 58-222153 A Japanese Patent Laid-Open No. 61-239248 JP-A-1-17066 Japanese Patent Laid-Open No. 61-109056 JP-A 62-67094 Japanese Unexamined Patent Publication No. 63-364 JP-A-63-366 Japanese Patent Laid-Open No. 2005-15682 Japanese Unexamined Patent Publication No. 63-198067 JP-A-1-123868 US Pat. No. 3,357,989 JP 58-18239 A Japanese Patent Laid-Open No. 5-263007 Japanese Patent Laid-Open No. 5-279591 Japanese Patent Laid-Open No. 58-100134 JP 61-273994 A JP 62-62367 A JP 59-44053 A Japanese Patent Laid-Open No. 1-221459 JP 60-59355 A JP-A-5-301292 JP 2001-290296 A JP-A-9-127711 JP 2002-23399 A JP 2007-334099 A Japanese Patent Laid-Open No. 3-9962 JP 2009-7523 A

Claims (10)

At least a photosensitive layer is provided on a conductive support, and the photosensitive layer is decarboxylated in the presence of an azo compound having a carboester group represented by the following general formula (I) dissolved in a solvent and a phthalocyanine pigment. An electrophotographic photosensitive member comprising a composite phthalocyanine pigment of an azo compound represented by the following general formula (a) and a phthalocyanine pigment obtained by esterification.

[Wherein A is a residue of an azo compound, and this residue A is bonded to n E groups via one or more heteroatoms, and The atom is selected from the group consisting of N and O and forms part of the residue A, and the E group is independently H (hydrogen atom) or a carboester group represented by the following formula: —C (= O) —O—R ₁ [wherein R ₁ represents a substituted or unsubstituted alkyl group, alkenyl group, alkynyl group, cycloalkyl group, cycloalkenyl group, or aralkyl group having 4 to 10 carbon atoms. ]. However, not all E groups are hydrogen atoms at the same time. n is an integer from 1 to 9. ]

[In the formula (a), A is as defined in the general formula (I), H represents a hydrogen atom, and n is an integer of 1 to 9. ]
The azo compound represented by the general formula (I) and the general formula (a) is an azo compound having a residue A represented by the following general formula (2). Electrophotographic photoreceptor.

(B represents the main skeleton of the azo compound, Cp represents a coupler component residue, and m represents an integer of 2 or 3.) The electrophotographic photoreceptor according to claim 2, wherein the Cp is a coupler component residue represented by at least one of the following general formulas (3) to (11).

In the general formulas (3) to (6), X, Y ¹ , Z, p and q each represent the following.
^{X: -OH, -N (R 1} ) (R 2) or -NHSO ₂ -R ^3.
(Here, R ¹ and R ² represent a hydrogen atom or a substituted or unsubstituted alkyl group, and R ³ represents a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group.)
Y ¹ : a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a carboxy group, a sulfone group, a substituted or unsubstituted sulfamoyl group, or —CON (R ⁴ ) (Y ² ). [R ⁴ represents a hydrogen atom, an alkyl group or a substituted product thereof, or a phenyl group or a substituted product thereof, Y ² represents a hydrocarbon ring group or a substituted product thereof, a heterocyclic group or a substituted product thereof, or —N═C (R ⁵ ) (R ⁶ ) (where R ⁵ is a hydrocarbon ring group or a substituted product thereof, a heterocyclic group or a substituted product thereof, or a styryl group or a substituted product thereof, and R ⁶ is a hydrogen atom, an alkyl group, a phenyl group or a substituted product thereof. Or R ⁵ and R ⁶ may form a ring together with the carbon atom to which they are attached. ]
Z: A hydrocarbon ring or a substituted product thereof, or a heterocyclic ring or a substituted product thereof.
p: an integer of 1 or 2.
q: An integer of 1 or 2.

(In the above formula, R ⁷ represents a substituted or unsubstituted hydrocarbon group, and X is as defined above.)

(In the above formula, A is a heterocycle containing a divalent aromatic hydrocarbon group or a nitrogen atom necessary for forming an N-containing heterocycle together with the two N atoms described in formula (8). Represents an atom-containing divalent group (these rings may be substituted or unsubstituted. X is as defined above.)

(In the above formula, R ⁸ represents an alkyl group, a carbamoyl group, a carboxy group or an ester thereof, Ar ¹ represents a hydrocarbon ring group or a substituent thereof, and X is the same as described above.)

(In the formula (10) and (11), R ⁹ represents a hydrogen atom or a substituted or unsubstituted hydrocarbon group, Ar ² represents a hydrocarbon ring group or a substitution product thereof. However, at the same time R ⁹ is hydrogen It is an atom and Ar ² does not become a cycloalkyl group or a cycloalkenyl group. The electrophotographic photoreceptor according to claim 2 or 3, wherein in the azo compound represented by the general formula (2), B is represented by the following general formula (12).

(However, R ¹¹ and R ¹² independently represent a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a carboxyl group, or an ester thereof.) The electrophotographic photoreceptor according to claim 2 or 3, wherein in the azo compound represented by the general formula (2), B is represented by the following general formula (13).

(However, R ¹⁹ and R ²⁰ independently represent a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a carboxyl group, and an ester thereof.) The electrophotographic photoreceptor according to claim 2 or 3, wherein in the azo compound represented by the general formula (2), B is represented by the following general formula (14).

(However, R ²⁴ , R ²⁵ , and R ²⁶ independently represent a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a carboxyl group, and an ester thereof.) The electrophotographic photosensitive member according to claim 1, wherein the phthalocyanine pigment contains at least titanyl phthalocyanine represented by the following structural formula.

(In the formula, M is TiO, and X _{1 to} X ₁₆ may be the same or different from each other, hydrogen atom, halogen atom, hydroxyl group, nitro group, cyano group, ester group, alkyl group, alkenyl group, alkoxyl group. Represents an aryl group or an aryloxyl group.) The image forming apparatus having at least a charging unit, an exposing unit, a developing unit, a transfer unit, and an electrophotographic photosensitive member, wherein the electrophotographic photosensitive member is the electrophotographic photosensitive member according to any one of claims 1 to 7. An image forming apparatus. A cartridge in which an electrophotographic photosensitive member and at least one means selected from a charging means, an exposure means, a developing means, a transfer means, and a cleaning means are mounted, and the cartridge is detachable from the apparatus main body. The image forming apparatus according to claim 8, wherein the image forming apparatus is provided. 8. A cartridge in which an electrophotographic photosensitive member and at least one means selected from a charging unit, an exposing unit, a developing unit, a transferring unit, and a cleaning unit are integrated. A process cartridge for an image forming apparatus, which is the electrophotographic photosensitive member according to claim 1.

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