JP2007248914A - Electrophotographic photoreceptor, process cartridge, and electrophotographic device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electrophotographic photoreceptor, a process cartridge, and an electrophotographic device that enables energy saving. <P>SOLUTION: The organic electrophotographic photoreceptor which has a setting-type surface layer laminated is characterized in that the surface layer contains a setting-charge transport component and a setting binder component, and a setting fluorinated carbon resin component and a polysiloxane component. The process cartridge is mounted with the electrophotographic photoreceptor. The electrophotographic device is mounted with the electrophotographic photoreceptor or the process cartridge and is not provided with a drum heater, and the fixing temperature is lower than 120°C. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

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

  In recent years, efforts to save resources and save energy for the purpose of protecting the global environment have become important. As part of this effort in the development of electrophotographic equipment, energy saving of equipment is being promoted along the top runner method. Here, the power consumption of the electrophotographic apparatus is large in the usage rate of the fixing means equipped with the electric heater. In order to save energy of the apparatus, it is advantageous to reduce the power consumption of the fixing device. This requires a lower fixing temperature.

  At present, the fixing temperature of an electrophotographic apparatus is generally about 150 ° C., and there is still room for lowering the temperature. When the fixing temperature is high, it takes a long time to start up the apparatus, so that not only energy saving but also convenience in use is lacking. For example, there are still many scenes where it is necessary to wait for the device to warm up immediately before a meeting, or experience that the copying machine cannot be copied for a long time due to a trouble with the fixing device. In consideration of the cold offset property and storage stability of the toner, it is desirable that the fixing temperature is 150 ° C. or lower, preferably 80 ° C. to 120 ° C. In the case of fixing only with pressure, the fixing temperature is preferably room temperature. In this case, maintainability is improved and the downtime of the apparatus can be shortened.

  In order to fix at such a low temperature, a corresponding toner is required. For example, as described in Patent Document 1, the softening temperature of the toner composition resin is controlled, a crystalline low molecular weight polyester resin is blended in the toner component in an incompatible state with other resins, and the glass transition temperature is relatively high. The fixing temperature can be lowered by blending a release agent having a low viscosity. (In the present invention, a dry developer prepared by dispersing a colorant in a natural or synthetic resin is referred to as a toner. In the case of a two-component developer containing a magnetic carrier such as iron powder, ferrite powder, or nickel powder. However, the components other than the carrier are distinguished from the toner components.) However, the use of the toner capable of fixing at such a low temperature causes filming of the toner component on the surface of the photoreceptor, resulting in filming such as image flow and resolution deterioration. An abnormal image to be output is often output.

  As a countermeasure, it is often the case that a photoconductor with low wear resistance is selected and the filming component is removed at the same time by scraping the surface of the photoconductor. In this case, the replacement life of the photoconductor is shortened. The energy required to recycle an unusable photoconductor increases as the recycling frequency increases. For this reason, there is a concern that the impact of the electrophotographic apparatus on the environment will rather increase.

  As another method, for example, an amorphous silicon photoreceptor having a high surface hardness as described in Patent Document 2 may be selected and a cleaning method may be devised. Since the manufacturing process of the amorphous silicon photoreceptor is a dry process, the manufacturing cost is high, and the object of use is limited to high-end machines with some exceptions. That is, it can be said that the method lacks versatility in terms of cost.

Thus, it can be said that no photoconductor that can be improved at the same time for both resource saving and energy saving has been obtained.
JP 2003-167384 A JP 2004-77963 A

  An object of the present invention is to provide an electrophotographic photosensitive member, a process cartridge, and an electrophotographic apparatus that can improve energy saving.

  The first aspect of the present invention is an organic electrophotographic photosensitive member in which a curable surface layer is laminated. A curable charge transport component, a curable binder component, and a curable fluororesin component and a polysiloxane component are formed on the surface layer. An electrophotographic photosensitive member characterized by comprising:

  A second aspect of the present invention is a process cartridge on which the electrophotographic photosensitive member according to the first aspect of the present invention is mounted.

  According to a third aspect of the present invention, the electrophotographic photosensitive member according to the first aspect of the present invention or the process cartridge according to the second aspect of the present invention is mounted, no drum heater is provided, and the toner fixing temperature is Is an electrophotographic apparatus having a temperature of less than 120 ° C.

  According to the first aspect of the present invention, an electrophotographic photosensitive member capable of improving energy saving can be provided.

  According to the second aspect of the present invention, it is possible to provide a process cartridge that makes it possible to improve energy saving.

  According to the third aspect of the present invention, an electrophotographic apparatus that can improve energy saving can be provided.

  Next, embodiments of the present invention will be described with reference to the drawings.

  For the embodiment of the present invention, for example, the following configurations [1] to [16] may be mentioned.

  [1] An organic electrophotographic photosensitive member in which a curable surface layer is laminated, wherein the surface layer contains a curable charge transport component, a curable binder component, a curable fluororesin component, and a polysiloxane component. An electrophotographic photoreceptor.

  [2] The electrophotographic photosensitive member according to [1], wherein the curable fluororesin component and the polysiloxane component are a curable fluororesin / siloxane graft polymer.

  [3] An organic solvent-soluble fluororesin component (A) in which the curable fluororesin / siloxane graft polymer has a radically polymerizable unsaturated bond moiety via at least a urethane bond, and a one-end radically polymerizable polysiloxane component (B), The electrophotographic photosensitive member according to [2], which is a graft copolymer of a radically polymerizable alkoxypolyalkylene glycol (C) with one terminal.

  [4] An organic solvent-soluble fluororesin component (A) in which the curable fluororesin / siloxane graft polymer has a radically polymerizable unsaturated bond moiety via at least a urethane bond, and a one-end radically polymerizable polysiloxane component (B), And a radical polymerizable monomer that does not react other than the polymerization reaction by a double bond with the organic solvent-soluble fluororesin (A) having a radical polymerizable unsaturated bond moiety via the urethane bond under the radical polymerization reaction conditions The electrophotographic photosensitive member according to [2], which is a graft copolymer of

  [5] The one-end radical polymerizable polysiloxane is represented by the following general formula (1):

（式中、Ｒ１は水素原子又は炭素原子数１〜１０の炭化水素基であり、Ｒ２、Ｒ３、Ｒ４、Ｒ５、及びＲ６は互いに同一でも異なっていてもよい水素原子又は炭素原子数１〜１０の炭化水素基であり、ｎは２以上の整数である）で示される片末端ラジカル重合性ポリシロキサン及び／又は下記一般式（２）

(In the formula, R1 is a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms, and R2, R3, R4, R5, and R6 may be the same or different from each other, and may be the same or different from each other. And n is an integer of 2 or more) and / or a radically polymerizable polysiloxane having one terminal and / or the following general formula (2)

（式中、Ｒ７は水素原子又は炭素原子数１〜１０の炭化水素基であり、Ｒ８、Ｒ９、Ｒ１０、Ｒ１１、及びＲ１２は互いに同一でも異なっていてもよい水素原子又は炭素原子数１〜１０の炭化水素基であり、ｐは０〜１０の整数であり、ｑは２以上の整数である）で示される片末端ラジカル重合性ポリシロキサン４〜４０重量％であることを特徴とする［３］又は［４］に記載の電子写真感光体。

(In the formula, R7 is a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms, and R8, R9, R10, R11, and R12 may be the same as or different from each other, and may be the same or different from each other. 4 to 40% by weight of one-terminal radically polymerizable polysiloxane represented by the formula (3), wherein p is an integer of 0 to 10 and q is an integer of 2 or more. ] Or the electrophotographic photosensitive member according to [4].

  [6] The one-terminal radical polymerizable alkoxy polyalkylene glycol is represented by the following general formula (3):

（式中、Ｒ１３は水素原子又は炭素原子数１〜１０の炭化水素基であり、Ｒ１４は炭素原子数１〜１０の炭化水素基であり、及びＲ１５は炭素原子数１〜１０の直鎖状又は分岐状のハロゲン原子で置換されていてもよい炭化水素基であり、ｌは１以上の整数であり、ｍは任意の整数である）で示される片末端ラジカル重合性アルコキシポリアルキレングリコール１〜２５重量％、及び（Ｄ）成分（Ａ）、（Ｂ）、及び（Ｃ）以外のラジカル重合性単量体２８〜９２重量％をランダム共重合してなるグラフト共重合体であることを特徴とする［３］に記載の電子写真感光体。

(In the formula, R13 is a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms, R14 is a hydrocarbon group having 1 to 10 carbon atoms, and R15 is a straight chain having 1 to 10 carbon atoms. Or a hydrocarbon group which may be substituted with a branched halogen atom, l is an integer of 1 or more, and m is an arbitrary integer). 25% by weight and (D) a graft copolymer obtained by random copolymerization of 28 to 92% by weight of radically polymerizable monomers other than components (A), (B), and (C) The electrophotographic photosensitive member according to [3].

  [7] The organic solvent-soluble fluororesin (A) having a radically polymerizable unsaturated bond moiety via the urethane bond is composed of an organic solvent-soluble fluororesin (A-1) having a hydroxyl group and a radical polymerizable monomer having an isocyanate group. The electrophotographic photosensitive member according to any one of [3] to [6], which is a reaction product with the monomer (A-2).

  [8] The radical polymerizable monomer (A-2) having an isocyanate group is selected from methacryloyl isocyanate, 2-isocyanatoethyl methacrylate, or m- or p-isopropenyl-α, α-dimethylbenzyl isocyanate. The electrophotographic photosensitive member according to any one of [3] to [6], which is one or more monomers.

  [9] The curable charge transport component is represented by the following general formula (4):

を表わす。）のラジカル重合性単量体であることを特徴とする［１］乃至［８］のいずれか一つに記載の電子写真感光体。

Represents. The electrophotographic photosensitive member according to any one of [1] to [8], which is a radically polymerizable monomer of (1).

  [10] The radical polymerizable compound having a monofunctional charge transport structure used for the cross-linked charge transport layer is represented by the following general formula (4):

を表わす。）のラジカル重合性単量体の一種以上であることを特徴とする［１］乃至［８］のいずれか一つに記載の電子写真感光体。

Represents. The electrophotographic photoreceptor according to any one of [1] to [8], wherein the electrophotographic photoreceptor is one or more of radically polymerizable monomers.

  [11] Any one of [1] to [10], wherein the curable binder component is at least one of trimethylolpropane triacrylate, caprolactone-modified dipentaerythritol hexaacrylate, and dipentaerythritol hexaacrylate. The electrophotographic photoreceptor described in 1.

  [12] The surface layer at the surface layer temperature in the electrophotographic apparatus before and after use of the electrophotographic apparatus when the elastic power of the curable surface layer is 50% or more and the CS5 wear amount is 1.5 mg / 10,000 rotations or less. Any one of [9] to [11], wherein the adhesion work with the toner is 20 mN / m or more and 75 mN / m or less, and the rotational force (torque) for driving the photosensitive member is 2.5 kgfcm or less. Electrophotographic photoreceptor.

  [13] A process cartridge comprising the electrophotographic photosensitive member according to any one of [1] to [12].

  [14] The electrophotographic photosensitive member according to any one of [1] to [12] or the process cartridge according to [13] is mounted, no drum heater is provided, and the toner fixing temperature is 120 ° C. An electrophotographic apparatus characterized by being less than or equal to.

  As a requirement for the inventor not to film the toner for low-temperature fixing on the surface of the photoreceptor, it is important that the adhesion work between the toner and the surface layer at the photoreceptor surface temperature when used in the apparatus is smaller than the adhesion energy between the toners. I thought. In particular, it is important that this value is a temperature condition when the surface temperature of the photosensitive member is used in the apparatus. Conventionally, several proposals have been made to specify the surface free energy of the photoconductor and the adhesion work (wetability) between the photoconductor and another substance to ensure specific performance. In particular, for the toner for low-temperature fixing, the specification of this parameter is not sufficient, and this specified value must be matched to the operating temperature. For polymerized toner, pulverized toner, color toner, and monochrome toner, the adhesion work between the toners calculated by the method described in JP-A-2005-062830 is about 100 mN / m. Similarly, the adhesion work between a general organic photoreceptor and a toner on the market is approximately 100 mN / m, and the toner tends to accumulate unless the surface layer of the photoreceptor is scraped. The same applies to the low-temperature fixing toner. Specifically, the adhesion work between the photosensitive member and the toner is preferably less than 75 mN / m. However, if the adhesion work is too small, development becomes impossible. Therefore, the adhesion work needs to be 20 mN / m or more as a condition that at least the photosensitive member and the toner adhere to each other. In order to form such a photoreceptor surface, it is embodied by blending a lubricant with the photoreceptor surface material. Fluorine resin is effective as the lubricant.

  In order to prevent filming of the photoconductor, it is also important to suppress damage to the photoconductor cleaner. Usually, the cleaner of the photosensitive member is in contact with the photosensitive member, and the magnitude of the load on the cleaner is indirect, but the rotational force (torque) is an index as the driving force of the photosensitive member. Excluding the energy used to drive the photoconductor, this rotational force is converted into energy required for abrasion of the photoconductor surface, energy required for heat generation, or energy required for deterioration of the member in contact with the photoconductor. It is thought that. When the rotational force is used under a small condition, deterioration of the cleaner is suppressed. Specifically, it is desirable to operate at 2.5 kgfcm or less.

  As a cleaner for the photoreceptor, a brush and a blade-shaped urethane rubber (referred to as a cleaning blade) are usually used. If the pressing force of the cleaning blade is reduced, the rotational force is reduced, but the cleaning function is weakened, so that a large adjustment cannot be made. Therefore, it is effective to reduce the friction of the photosensitive member in order to reduce the rotational force. In particular, the heat and photocurable resin surfaces have a higher rotational force than the thermoplastic resin surface, and improvements are desired when using curable resins.

  The effect of reducing the friction of the photoreceptor when silicone oil is blended on the surface of the photoreceptor is generally known. However, it is difficult for silicone oil to obtain sustainability due to the nature of bleeding out. For this reason, in order to make the rotational force of the photoreceptor less than a predetermined value, it is preferable to fix silicone oil on the surface of the photoreceptor.

  In order to prevent toner filming, it is advantageous to use a material having a small plastic deformation for the surface of the photoreceptor. Although details are unknown at this time, if the surface of the photoconductor becomes more flexible, for example, like a thick vinyl sheet, the tackiness increases and the surface of the photoconductor becomes easily soiled. Specifically, when the elastic power (ηIT) obtained by the dynamic hardness test is 50% or more, contamination of the photoreceptor surface is easily prevented. In order to increase the elastic power, a cross-linked resin is preferably used.

  In addition, it is desirable to suppress the replacement frequency of the photoconductor in order to save resources. For this purpose, it is important to enhance the wear resistance of the photoreceptor surface. Several methods have been proposed for the index of wear resistance. Of these, the Taber abrasion test using CS5 is a test method for gradually abrading the extreme surface layer of the test object. For this reason, the S / N of the wear amount obtained by the test is often large. The CS5 wear amount is preferably as small as possible. Specifically, it can be said that if the load is 1 kgf and the load is 1.5 mg / 10,000 rotations or less, the mechanical strength of the photoreceptor is strong and the effect of saving resources can be obtained.

  As described above, no policy has been proposed yet that satisfies the requirements of the four items at the same time.

  JP-A-11-311875 discloses a relationship between surface free energy and cleaning properties as a known technique relating to the first surface free energy. However, it is not possible to know a specific measure for the apparatus using the organic photoreceptor, from this case. Further, the rotational force of the photoconductor as the second requirement is disclosed in, for example, Japanese Patent Application Laid-Open No. 2001-265039. However, it is not a direct content that prevents the cleaner from deteriorating.

  In contrast, it has been found that it is effective to blend a curable fluororesin component and a curable polysiloxane component that do not cause bleed-out into the surface material of the photoreceptor. In particular, the use of the curable fluororesin / siloxane graft polymer described in JP-A-2000-119354 and JP-A-2000-119355 as a material for the surface layer of the photoreceptor is effective in reducing the adhesive work and the rotational force. I found out.

  The photoreceptor surface layer using this material is more likely to have a higher elastic work rate if a heat- or photo-curing resin having a crosslinked structure is used than a thermoplastic resin such as polycarbonate. This seems to be due to the molecular structure taking a network shape. Among these, a photocurable resin using trimethylolpropane triacrylate or caprolactone-modified dipentaerythritol hexaacrylate or dipentaerythritol hexaacrylate as a binder component has a small CS5 wear amount and is advantageous as a measure for forming a mechanically tough surface layer. is there.

  Separately, when this curable surface layer is laminated on the surface of the photoreceptor, it is necessary to ensure electrostatic characteristics capable of outputting an image. By imparting charge transportability to this surface layer, electrostatic characteristics are easily secured. In particular, the following curable charge transport materials are advantageous.

(Photo-curing type)
(General formula 4)

（式中、ｏ、ｐ、ｑはそれぞれ０又は１の整数、Ｒａは水素原子、メチル基を表わし、Ｒｂ、Ｒｃは水素原子以外の置換基で炭素数１〜６のアルキル基を表わし、複数の場合は異なっても良い。ｓ、ｔは０〜３の整数を表わす。Ｚａは単結合、メチレン基、エチレン基、

(Wherein, o, p and q are each an integer of 0 or 1, Ra represents a hydrogen atom or a methyl group, Rb and Rc represent a substituent other than a hydrogen atom and an alkyl group having 1 to 6 carbon atoms, And s and t each represents an integer of 0 to 3. Za is a single bond, a methylene group, an ethylene group,

を表わす。）
（熱硬化型）
熱硬化型の電荷輸送成分は以下の一般式（５）乃至（７）が有利である。また、これらの化合物に共通して分子量を官能基（活性水素）数で除した値が小さいと硬化型保護層中の硬化剤の含有量を高めてしまい、結果、硬化可能な電荷輸送物質の最大含有量を制約してしまう。処方設計上、この値は大きい材料が好ましく、具体的にはが２００以上の材料が好ましい。

Represents. )
(Thermosetting type)
The following general formulas (5) to (7) are advantageous for the thermosetting charge transport component. In addition, if the value obtained by dividing the molecular weight by the number of functional groups (active hydrogen) is small in common with these compounds, the content of the curing agent in the curable protective layer is increased. Limits the maximum content. In terms of formulation design, a material having a large value is preferable, and specifically, a material having 200 or more is preferable.

  (General formula 5)

式中、Ｒ２は水素原子、アルキル基、フッ素原子、シアノ基、フェニル基又はハロゲン原子で置換されたアルキル基、Ｃ１〜Ｃ４のアルキル基で置換されたフェニル基で置換されたアルキル基、アリール基、フッ素原子、シアノ基、フェニル基又はハロゲン原子で置換されたアリール基、Ｃ１〜Ｃ４のアルキル基で置換されたフェニル基で置換されたアリール基を表し、Ｒ３は水素原子、アルキル基、フッ素原子、シアノ基、フェニル基又はハロゲン原子で置換されたアルキル基、Ｃ１〜Ｃ４のアルキル基で置換されたフェニル基で置換されたアルキル基、アリール基、フッ素原子、シアノ基、フェニル基又はハロゲン原子で置換されたアリール基、Ｃ１〜Ｃ４のアルキル基で置換されたフェニル基で置換されたアリール基、ハロゲン原子を表し、Ｒ３は水素原子を表し、Ａｒ１、Ａｒ２はアリール基、ハロゲン原子又はアルキル基で置換されたアリール基を表す。但し、Ｒ３が水素原子、且つＡｒ１及びＡｒ２がｐ−トリル基である場合を除く。
Ｘは下記（ａ）〜（ｄ）のいずれかを表す。

In the formula, R2 represents a hydrogen atom, an alkyl group, a fluorine atom, a cyano group, an alkyl group substituted with a phenyl group or a halogen atom, an alkyl group substituted with a phenyl group substituted with a C1-C4 alkyl group, an aryl group , A fluorine atom, a cyano group, an aryl group substituted with a phenyl group or a halogen atom, an aryl group substituted with a phenyl group substituted with a C1-C4 alkyl group, and R3 represents a hydrogen atom, an alkyl group, a fluorine atom An alkyl group substituted with a cyano group, a phenyl group or a halogen atom, an alkyl group substituted with a phenyl group substituted with a C1-C4 alkyl group, an aryl group, a fluorine atom, a cyano group, a phenyl group or a halogen atom. Substituted aryl group, aryl group substituted with phenyl group substituted with C1-C4 alkyl group, halogen atom And, R3 represents a hydrogen atom, Ar @ 1, Ar @ 2 represents an aryl group, an aryl group substituted with a halogen atom or an alkyl group. However, the case where R3 is a hydrogen atom and Ar1 and Ar2 are p-tolyl groups is excluded.
X represents any of the following (a) to (d).

(A) alkylene group
(B) an alkylene group substituted by a fluorine atom, a cyano group, a phenyl group, or a phenyl group substituted by a halogen atom or a C1-C5 alkyl group
(C) Arylene group
(D) Group represented by the following general formula (8)
(General formula 8)

｛式中、Ｙは−Ｏ−、−Ｓ−、−ＳＯ−、−ＳＯ２−、−ＣＯ−及び以下の２価基を表す。

{In the formula, Y represents -O-, -S-, -SO-, -SO2-, -CO- and the following divalent groups.

（ここで、Ｒ５、Ｒ６は水素原子、アルキル基、前記（ｃ）で定義された置換基を有するアルキル基、アルコキシ基、ハロゲン原子、アリール基、前記（ｅ）で定義された置換基を有するアリール基、アミノ基、ニトロ基、シアノ基を表し、ｐ、ｑ、ｒ、ｓは１〜１２の整数を表す）｝
（一般式６）

(Here, R5 and R6 have a hydrogen atom, an alkyl group, an alkyl group having a substituent defined in (c), an alkoxy group, a halogen atom, an aryl group, and a substituent defined in (e) above. Represents an aryl group, an amino group, a nitro group, or a cyano group, and p, q, r, and s represent an integer of 1 to 12)}
(General formula 6)

Ｒ７、Ｒ８は置換もしくは無置換のアリール基を表す。Ｒ７、Ｒ８は同一であっても異なってもよい。

R7 and R8 represent a substituted or unsubstituted aryl group. R7 and R8 may be the same or different.

The arylene group represented by Ar3, Ar4 and Ar5 includes the same divalent group of an aryl group as R5 and R6, and may be the same or different.
X is the same as that mentioned in the general formula (5).

  (General formula 7)

Ｒ９、Ｒ１０は置換もしくは無置換のアリール基を表す。Ｒ９、Ｒ１０は同一であっても異なってもよい。

R9 and R10 represent a substituted or unsubstituted aryl group. R9 and R10 may be the same or different.

The arylene group represented by Ar6 and Ar7 includes the same divalent group of an aryl group as R9 and R10, and may be the same or different.
X is the same as that mentioned in the general formula (5).

  Low-temperature fixing of an electrophotographic apparatus requires toner for low-temperature fixing, but in addition, it cannot be established without a technique for making full use of this toner. Prevention of filming of the photosensitive member is extremely important for using the low-temperature fixing toner. The surface layer of the photoconductor produced as described above can prevent toner filming and realize low-temperature fixing of the apparatus. In addition, as will be apparent from the examples described below, the organic photoconductor achieves abrasion resistance equivalent to an amorphous silicon photoconductor, and the electrophotographic photoconductor of the present invention has environmental performance compared to conventional photoconductors. It can be said that the photoconductor is extremely high.

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

  First, an electrophotographic apparatus used in the present invention will be described with reference to the drawings.

  Desktop or floor using indirect electrophotography (xerographic method) such as facsimile, laser printer, electrophotographic copying machine, direct plate-making machine and their combined machines, which are widely used as devices for image formation In general, an image forming apparatus of a type includes an electrophotographic photosensitive member (or an image carrier), a charging device, an image exposure device, a developing device, a transfer device, a separation device, a cleaning device, a static elimination device, a fixing device, and copy paper (a transfer target) Body), a paper discharge tray, and the like.

  FIG. 1 shows a schematic diagram of an image forming apparatus using an electrophotographic system.

  Electrophotographic photoreceptors 1 (hereinafter simply referred to as photoreceptors) used for image formation include selenium (a-Se, a-Se2Se3, a-SeTe, etc.), silicon (a-Si: H, a-Si). : Ge: H, etc.), CdSe series, CdS series, ZnO series and other photosensitive materials are known. In the present invention, an organic photoreceptor is mounted on which a curable surface layer containing a curable charge transporting component and a curable binder component, and a curable fluororesin component and a polysiloxane component are laminated.

  Charging is performed by a charging device 2 disposed opposite to the photoreceptor 1.

  As the charging device 2, a corona charging device, a contact charging device, and a proximity charging device (or a non-contact charging device) are known.

  In the corona charging device, a discharge wire (for example, tungsten wire) of 40 to 60 (μm) is placed in a U-shaped shield case, a DC voltage of −4000 to −7000 V is applied, and 8 from the photoconductor. It is a corona charging device that is separated by about 10 mm and is charged by silent discharge.

  When negative charging is performed, since the discharge is non-uniform, a grid is usually installed to equalize the charging potential.

  The contact charging device and the proximity charging device are a brush-like charging member composed of carbon fiber or a low resistance material such as carbon dispersed in chemical fiber, and a resistance-controlled fiber, or epichlorohydrin rubber alone, or further carbon. Addition to control resistance, roller-shaped charging member configured by adding fluororesin or silica as required, roller shape with resistance control by dispersing carbon, metal powder, ionic conductive material in resin There are charging members and the like. The charging members are mounted on the unit and are placed in contact with the photosensitive member 1 or separated from the photosensitive member by about 30 to 80 μm. A DC voltage of −400 to −1000 (V) or a voltage in which an AC voltage of 800 to 2500 V / 800 to 4500 Hz is superimposed on the DC voltage is applied to the charging member.

  The charging level of the photoreceptor is set to about -400 to -800V.

  Although the corona charging device is excellent in charging followability, there is an environmental problem because ozone is generated in a large amount (around 10 ppm). On the other hand, the contact charging method or the proximity charging method (or non-contact charging) has a problem that the charging member is contaminated and charging non-uniformity easily occurs because it is in contact with or close to the photosensitive member. In recent years, it has been widely used as a charging means because it has the advantages of being small and energy saving, producing less ozone (about 0.05 to 0.3 ppm) and being excellent in environmental properties.

  After the photoreceptor 1 is uniformly charged, the original image and the signal from the personal computer are irradiated with a dot pattern by the image exposure device 3 including a CCD, an LD element or an LED element, a polygon mirror, a filter, a cylindrical lens, and the like. As a result, an electrostatic latent image (light / dark potential difference) of a digital pattern is formed on the photoreceptor 1.

  The electrostatic latent image is developed by the developing device 4 using a magnet brush developing method.

  The developing device contains a magnetic powder called a carrier having an average particle size of about 40 to 80 μm and a developer composed of toner having a particle size of about 4 to 10 μm, and the toner concentration is set to about 3 to 8% by weight. Is done. A developing bias is applied to the developing device for development.

  The toner used in the developer includes a pulverized toner manufactured by a mechanical manufacturing method having irregular shapes and irregularities, and a polymerized toner manufactured by a chemical manufacturing method (such as a suspension polymerization method or an emulsion polymerization method). However, in recent years, with the demand for high image quality, there is a tendency to increase the use of polymerized toner that is less expensive than pulverized toner, has a relatively uniform shape, and has a substantially uniform charge.

  The toner image obtained by the development is transferred onto a transfer medium (copy paper) 11 conveyed from the paper feed tray 10 by the transfer device 5 to which a voltage opposite to the toner band electrode is applied, and the fixing device. 9 is carried and fixed to form a hard copy 13, which is then discharged to the paper discharge tray 12.

  After the transfer, the residual toner on the photoconductor is cleaned by a cleaning device 7 including a cleaning blade using a rubber-like elastic body as a blade, and then the entire surface of the photoconductor is irradiated by a static eliminator 8 to neutralize the internal latent image. Then, it is electrically initialized and a series of copying cycles is completed.

  The image forming apparatus is not limited to the configuration shown in FIG. 1, and an electrophotographic apparatus in which the photosensitive member 1 is formed into a belt shape, a photosensitive member is color-printed with a tandem layout, or is printed via an intermediate transfer member. Is also used.

  Further, the image forming means as described above may be fixedly incorporated in a copying machine, a facsimile, or a printer, but may be incorporated in these apparatuses in the form of a process cartridge. The process cartridge according to the present invention is a module including a photosensitive member, and further including a charging unit, an exposure unit, a developing unit, a transfer unit, a cleaning unit, and a charge eliminating unit.

  Next, the electrophotographic photosensitive member of the present invention will be described in detail with reference to the drawings.

  FIG. 2 is a cross-sectional view schematically showing an example of an electrophotographic photoreceptor having still another layer structure of the present invention. A charge generation layer 25, a charge transport layer 26, and a curable protective layer are formed on a conductive support 21. 28 is provided.

  FIG. 3 is a cross-sectional view schematically showing an example of an electrophotographic photoreceptor having still another layer structure of the present invention, in which an undercoat layer 25 is provided between the conductive support 21 and the charge generation layer 22, A charge transport layer 26 and a curable protective layer 28 are provided on the charge generation layer 22.

  Examples of the conductive support 21 include those having a volume resistance of 1010 Ω · cm or less, such as metals such as aluminum, nickel, chromium, nichrome, copper, silver, gold, platinum, and iron, tin oxide, and indium oxide. A film or cylindrical plastic or paper coated with an oxide by vapor deposition or sputtering, or a plate made of aluminum, aluminum alloy, nickel, stainless steel, and the like, and a Drawing Ironing method, an Impact Ironing method, an Extruded method. A tube that has been surface-treated by cutting, superfinishing, polishing, or the like can be used after forming a raw tube by a method such as the Ironing method, the Extruded Drawing method, or the cutting method.

  In the electrophotographic photoreceptor used in the present invention, an undercoat layer 24 can be provided between the conductive support and the photosensitive layer. The undercoat layer is provided for the purpose of improving adhesiveness, preventing moire, improving coatability of the upper layer, and preventing charge injection from the conductive support.

  The undercoat layer is usually composed mainly of a resin. Usually, since the photosensitive layer is applied on the undercoat layer, the resin used for the undercoat layer is preferably a thermosetting resin that is hardly soluble in an organic solvent. In particular, polyurethane, melamine resin, and alkyd-melamine resin are particularly preferable materials because many of them sufficiently satisfy the above purpose. The resin can be used as a coating material which is appropriately diluted with a solvent such as tetrahydrofuran, cyclohexanone, dioxane, dichloroethane, butanone and the like.

  In addition, fine particles such as metal or metal oxide may be added to the undercoat layer in order to adjust conductivity and prevent moire. In particular, titanium oxide is preferably used.

  The fine particles are dispersed in a ball mill, attritor, sand mill or the like using a solvent such as tetrahydrofuran, cyclohexanone, dioxane, dichloroethane, or butanone to obtain a coating material in which the dispersion and the resin component are mixed.

  The undercoat layer is formed by depositing the above-mentioned paint on a support by a dip coating method, spray coating method, bead coating method or the like and, if necessary, heat curing.

  In many cases, the thickness of the undercoat layer is suitably about 2 to 5 μm. When the accumulation of the residual potential of the photoconductor becomes large, it is preferable to make it less than 3 μm.

  The photosensitive layer in the present invention is preferably a laminated photosensitive layer in which a charge generation layer and a charge transport layer are sequentially laminated.

  Of the layers in the multilayer photoconductor, the charge generation layer 25 will be described. The charge generation layer refers to a part of the laminated photosensitive layer and has a function of generating charges by exposure. This layer is mainly composed of a charge generating substance among the contained compounds. For the charge generation layer, a binder resin may be used as necessary. As the charge generation material, inorganic materials and organic materials can be used.

  On the other hand, as the organic material, known materials can be used, for example, metal phthalocyanine such as titanyl phthalocyanine and chlorogallium phthalocyanine, metal-free phthalocyanine, azulenium salt pigment, squaric acid methine pigment, symmetrical type having a carbazole skeleton. Alternatively, an asymmetric azo pigment, a symmetric or asymmetric azo pigment having a triphenylamine skeleton, a symmetric or asymmetric azo pigment having a fluorenone skeleton, a perylene pigment, and the like can be given. Among these, metal phthalocyanines, symmetric or asymmetric azo pigments having a fluorenone skeleton, symmetric or asymmetric azo pigments having a triphenylamine skeleton, and perylene pigments have a high quantum efficiency of charge generation, and thus are suitable for the present invention. It is suitable as a material to be used. These charge generation materials may be used alone or as a mixture of two or more.

  The binder resin used as necessary for the charge generation layer includes polyamide, polyurethane, epoxy resin, polyketone, polycarbonate, polyarylate, silicone resin, acrylic resin, polyvinyl butyral, polyvinyl formal, polyvinyl ketone, polystyrene, poly-N-. Examples thereof include vinyl carbazole and polyacrylamide. Moreover, the polymeric charge transport material mentioned later can also be used. Of these, polyvinyl butyral is often used and is useful. These binder resins may be used alone or as a mixture of two or more.

  Methods for forming the charge generation layer are roughly classified into a vacuum thin film preparation method and a casting method from a solution dispersion system.

  Examples of the former method include a vacuum deposition method, a glow discharge decomposition method, an ion plating method, a sputtering method, a reactive sputtering method, and a CVD (chemical vapor deposition) method. Can be formed satisfactorily.

  In addition, in order to provide the charge generation layer by the casting method, the above-described inorganic or organic charge generation material may be combined with a binder resin, if necessary, using a solvent such as tetrahydrofuran, cyclohexanone, dioxane, dichloroethane, butanone, ball mill, attritor. The dispersion may be dispersed by a sand mill or the like, and the dispersion may be diluted appropriately. Among these solvents, methyl ethyl ketone, tetrahydrofuran, and cyclohexanone are preferable because they have a lower environmental impact than chlorobenzene, dichloromethane, toluene, and xylene. The coating can be performed by a dip coating method, a spray coating method, a bead coating method, or the like.

  The thickness of the charge generation layer provided as described above is usually about 0.01 to 5 μm.

  When it is necessary to reduce the residual potential and increase the sensitivity, these characteristics are often improved by increasing the thickness of the charge generation layer. On the other hand, the chargeability often deteriorates, such as the charge charge retention and space charge formation. From these balances, the thickness of the charge generation layer is more preferably in the range of 0.05 to 2 μm.

If necessary, a low molecular compound such as an antioxidant, a plasticizer, a lubricant, and an ultraviolet absorber and a leveling agent may be added to the charge generation layer. As these materials, for example, materials described in paragraph numbers [0127] to [0160] of JP-A-2003-322984 are used. These compounds can be used alone or as a mixture of two or more. When a low molecular weight compound and a leveling agent are used in combination, sensitivity deterioration often occurs. For this reason, the amount of these used is generally 0.1 to 20 phr, preferably 0.1 to 10 phr, and the amount of the leveling agent used is suitably about 0.001 to 0.1 phr.
Next, the charge transport layer 26 will be described.

  The charge transport layer refers to a part of the laminated photosensitive layer that functions to inject and transport charges generated in the charge generation layer and to neutralize the surface charge of the photoreceptor provided by charging. The main component of the charge transport layer can be said to be a charge transport component and a binder component that binds the charge transport component.

  Examples of materials that can be used for the charge transport material include low molecular weight electron transport materials, hole transport materials, and polymer charge transport materials.

  Examples of the electron transporting material include electron accepting materials such as asymmetric diphenoquinone derivatives, fluorene derivatives, and naphthalimide derivatives.

  These electron transport materials may be used alone or as a mixture of two or more.

  As the hole transport material, an electron donating material is preferably used.

  Examples thereof include oxazole derivatives, oxadiazole derivatives, imidazole derivatives, triphenylamine derivatives, butadiene derivatives, 9- (p-diethylaminostyrylanthracene), 1,1-bis- (4-dibenzylaminophenyl) propane, Examples include styryl anthracene, styryl pyrazoline, phenylhydrazones, α-phenyl stilbene derivatives, thiazole derivatives, triazole derivatives, phenazine derivatives, acridine derivatives, benzofuran derivatives, benzimidazole derivatives, and thiophene derivatives.

  These hole transport materials may be used alone or as a mixture of two or more.

  Moreover, the polymeric charge transport material represented below can be used. For example, a polymer having a carbazole ring such as poly-N-vinylcarbazole, a polymer having a hydrazone structure exemplified in JP-A-57-78402, etc., exemplified in JP-A-63-285552, etc. The polysilylene polymer to be used, and aromatic polycarbonates exemplified by general formula (1) to general formula (6) of JP-A No. 2001-330973. These polymer charge transport materials can be used alone or as a mixture of two or more. In particular, the exemplified compounds described in JP-A-7-292095 are useful because of their good electrostatic characteristics.

  The polymer charge transport material is a suitable material for preventing the surface layer from being poorly cured when the curable protective layer is laminated, as compared with the low molecular weight charge transport material. In addition, since the charge transporting substance has a high molecular weight, it has excellent heat resistance, and is advantageous in that it is less susceptible to deterioration due to curing heat when a curable protective layer is formed.

  Examples of the polymer compound that can be used as the binder component of the charge transport layer include polystyrene, polyester, polyvinyl, polyarylate, polycarbonate, acrylic resin, silicone resin, fluorine resin, epoxy resin, melamine resin, urethane resin, and phenol resin. And thermoplastic or thermosetting resins such as alkyd resins. Of these, polystyrene, polyester, polyarylate, and polycarbonate are useful because many of them have good charge transfer characteristics when used as a binder component of a charge transport component. Further, since the charge transport layer has a curable protective layer or a protective layer laminated thereon, the charge transport layer is not required to have mechanical strength as compared with the conventional charge transport layer. For this reason, a material such as polystyrene, which is highly transparent but has a low mechanical strength and is difficult to apply in the prior art, can be effectively used as the binder component of the charge transport layer.

  These polymer compounds can be used singly or as a mixture of two or more kinds, or as a copolymer composed of two or more kinds of these raw material monomers, and further copolymerized with a charge transport material.

  When an electrically inactive polymer compound is used for modifying the charge transport layer, a cardo polymer type polyester having a bulky skeleton such as fluorene, a polyester such as polyethylene terephthalate or polyethylene naphthalate, or a C type polycarbonate is used. Polycarbonate in which the 3,3 ′ portion of the phenol component is alkyl-substituted with respect to a bisphenol-type polycarbonate, polycarbonate in which the geminal methyl group of bisphenol A is substituted with a long-chain alkyl group having 2 or more carbon atoms, biphenyl or biphenyl Polycarbonate having an ether skeleton, polycarbonate having a long chain alkyl skeleton such as polycaprolactone and polycaprolactone (for example, described in JP-A-7-292095), acrylic resin, polystyrene, hydrogenated Diene is valid.

  Here, the electrically inactive polymer compound refers to a polymer compound that does not include a chemical structure exhibiting photoconductivity such as a triarylamine structure.

  When these resins are used in combination with a binder resin as an additive, the addition amount is preferably 50 wt% or less with respect to the total solid content of the charge transport layer due to restrictions on light attenuation sensitivity.

  When a low molecular charge transport material is used, the amount used is 40 to 200 phr, preferably about 70 to 100 phr. When a polymer charge transport material is used, a material in which the resin component is copolymerized in an amount of about 0 to 200 parts by weight, preferably about 80 to 150 parts by weight with respect to 100 parts by weight of the charge transport component is preferably used.

  When two or more kinds of charge transport materials are contained in the charge transport layer, it is preferable that the difference in ionization potential is small. Specifically, by setting the difference in ionization potential to 0.10 eV or less, Can be prevented from becoming a charge trap of the other charge transport material.

  Regarding the relationship between the ionization potentials, the difference between the charge transporting material contained in the charge transporting layer and the curable charge transporting material described later is preferably 0.10 eV.

  In addition, the ionization potential value of the charge transport material in the present invention is a numerical value obtained by measuring by a general method using the atmospheric atmospheric ultraviolet photoelectron analyzer AC-1 manufactured by Riken Keiki Co., Ltd.

  In order to satisfy high sensitivity, the charge transport component is preferably added in an amount of 70 phr or more. In addition, α-phenylstilbene compounds, benzidine compounds, butadiene compound monomers, dimers, and polymer charge transport materials having these structures in the main chain or side chain are materials having high charge mobility. Many are useful.

  Examples of the dispersion solvent that can be used in preparing the charge transport layer coating solution include ketones such as methyl ethyl ketone, acetone, methyl isobutyl ketone, and cyclohexanone, ethers such as dioxane, tetrahydrofuran, and ethyl cellosolve, toluene, xylene, and the like. Examples include aromatics, halogens such as chlorobenzene and dichloromethane, and esters such as ethyl acetate and butyl acetate. Of these, methyl ethyl ketone, tetrahydrofuran, and cyclohexanone are preferable because they have a lower environmental impact than chlorobenzene, dichloromethane, toluene, and xylene. These solvents can be used alone or in combination.

  The charge transport layer can be formed by dissolving or dispersing a mixture or copolymer mainly composed of a charge transport component and a binder component in an appropriate solvent, and applying and drying the mixture. As the coating method, a dipping method, a spray coating method, a ring coating method, a roll coater method, a gravure coating method, a nozzle coating method, a screen printing method, or the like is employed.

  Since a curable protective layer is laminated on the upper layer of the charge transport layer, the thickness of the charge transport layer in this configuration need not be designed to increase the thickness of the charge transport layer in consideration of film scraping in actual use. Thus, it is possible to reduce the thickness.

  The film thickness of the charge transport layer is practically about 15 to 40 μm, preferably about 15 to 30 μm for the purpose of ensuring the necessary sensitivity and charging ability.

  If necessary, a low-molecular compound such as an antioxidant, a plasticizer, a lubricant, and an ultraviolet absorber described in the charge generation layer and a leveling agent may be added to the charge transport layer. These compounds can be used alone or as a mixture of two or more. When a low molecular weight compound and a leveling agent are used in combination, sensitivity deterioration often occurs. For this reason, the amount of these used is generally 0.1 to 20 phr, preferably 0.1 to 10 phr, and the amount of the leveling agent used is suitably about 0.001 to 0.1 phr.

  Next, the curable surface layer 28 will be described.

  For the curable surface layer, it is necessary to select a material that forms a three-dimensional network structure through a crosslinking reaction. In particular, it is necessary to contain (A) a curable fluororesin component, a polysiloxane component, (B) a curable charge transport component, and (C) a curable binder component.

(A) Curable fluororesin component and polysiloxane component Any material can be used for the curable fluororesin component and the polysiloxane component as long as they can be cured. For example, these materials include Neos Corporation's Fargent Series, Toa Gosei Corporation Reseda Series, Zaflon Series, and Nippon Oil & Fats Corporation Modiper F Series. Further, examples of the curable polysiloxane include Chisso Silaplane Series, BYK Chemie BYK-UV Series, BYK-SILCLEAN 3700, Toagosei Cymac Series, and the like.

  In particular, in the present invention, those obtained by grafting a polysiloxane component to the main skeleton of a fluororesin as described in JP-A Nos. 2000-119354 and 2000-119354 are preferable. However, it must have a functional group that can be cured by radical polymerization or heat curing. As this material, for example, the hydrophobic resin ZX series marketed by Fuji Chemical Industry Co., Ltd. can be obtained.

  An appropriate amount of this component is 5 to 10 wt% of the total solid content of the curable surface layer.

(B) Curable charge transporting component The curable charge transporting component is preferably a material excellent in injectability from the underlying charge transporting layer and having a high charge transporting ability. On the other hand, the use of a charge transporting monomer used for the synthesis of a polymer charge transporting material exemplified in JP-A-2001-330973 has a high track record and is extremely useful. In addition, if the amount of substance (equivalent) per functional group is small when curing is included in the molecular skeleton, the content of the curing agent in the curable protective layer is increased, resulting in the maximum content of the curable charge transport material. Will be constrained. In terms of formulation design, a material having a large equivalent weight is preferable. Specifically, a material having an equivalent weight of 200 or more may be selected. In the thermosetting type, it can be said that utilization of the above-described compounds of the general formulas 5 to 7 is reasonable. For the photo-curing type, a radical polymerizable charge transport material described in JP-A No. 2004-302451 is useful. The compound of general formula 4 described above often exhibits particularly excellent electrostatic properties.

  The blending ratio of the curable charge transport component is designed in accordance with the sensitivity characteristics in the electrophotographic apparatus, but is generally 7.5 wt% to 60 wt% with respect to the total solid content of the curable surface layer. There are many.

(C) Curable binder component It can be said that melamine, isocyanate, and organosilane are suitable for the curable binder component in the thermosetting type from the balance of film strength and electrostatic characteristics. These compounds include Dainippon Ink & Chemicals, Inc. Super Becamine G series (melamine), L series (melamine), Nippon Polyurethane Co., Ltd. HX series (HDI polyisocyanate), Nippon Seika Co., Ltd. NSC series (organosilica sol), What is marketed as Ohashi Chemical Co., Ltd. heatless glass GO series (organosilane) can be obtained. In order to obtain smoothness of the film, a leveling agent such as BYK-3 series marketed by Big Chemie may be blended in an amount of about 0.1 to 1 phr.

  For the photo-curing type, it is preferable to use a trifunctional or higher functional radical polymerizable monomer having no charge transporting structure described in JP-A No. 2004-302451. Particularly preferred are trimethylolpropane triacrylate, caprolactone-modified dipentaerythritol hexaacrylate, and dipentaerythritol hexaacrylate. These can be obtained from reagent manufacturers such as Tokyo Kasei Co., Ltd., Nippon Kayaku KAYARD DPCA series, DPHA series and the like.

  To this, an initiator such as Ciba Specialty Chemicals Irgacure 184 may be added in an amount of about 5 to 10 wt% based on the total solid content.

  The dispersion solvent used in preparing the curable surface layer coating is preferably a solvent that sufficiently dissolves the monomer. In addition to the ethers, aromatics, halogens, esters described above, cellosolves such as ethoxyethanol, Mention may be made of propylene glycols such as 1-methoxy-2-propanol. Of these, methyl ethyl ketone, tetrahydrofuran, cyclohexanone, and 1-methoxy-2-propanol are preferable because they have a lower environmental impact than chlorobenzene, dichloromethane, toluene, and xylene. These solvents can be used alone or in combination.

  Examples of the curable surface layer forming method include dipping method, spray coating method, ring coating method, roll coater method, gravure coating method, nozzle coating method, and screen printing method. In many cases, since the pot life of the coating liquid is not long, a means capable of coating a necessary amount with a small amount of paint is advantageous in consideration of the environment and cost. Of these, the spray coating method and the ring coating method are preferred.

  In the case of the thermosetting type, when the curable protective layer coating solution coating is heat-dried, it is important that the coating does not become tack-free. Thereby, insufficient curing and non-uniform curing can be suppressed. In addition, if the curing temperature is too high or too low, a curing failure occurs, so this setting also affects the stabilization of quality. In order to proceed with sufficient curing, it is better to avoid sudden volatilization of the solvent. On the other hand, if the curing rate is too slow, the curable protective layer itself has a film thickness unevenness, cracks, or alteration of the base such as crystallization of the charge transport material, so it is necessary to heat at an appropriate temperature.

  The specific set temperature needs to be adjusted depending on the material used, but the endothermic peak temperature of the protective layer coating solution is X (° C), the boiling point of the coating solution solvent is Y (° C), and the protective layer is formed. When the maximum heat drying temperature is Z (° C.), it is preferable to proceed the curing at a set temperature that satisfies the following conditions.

(Equation 1)
X <Z <Y
Here, the endothermic peak temperature of the protective layer coating solution is a value obtained by a DSC measuring apparatus. In the present invention, measurement is performed using a differential scanning calorimeter Thermoplus DSC8230 manufactured by Rigaku Corporation. For the measurement, an open-type aluminum pan was used, and a DSC curve at the time of first scan obtained when the temperature range from 40 ° C. to 200 ° C. was raised at a scanning rate of 10 ° C./min was adopted.

  As the crosslinking reaction proceeds, the solvent often volatilizes even when the heating temperature is lower than the boiling point of the solvent. The diffusion of the solvent into the atmosphere and the exothermic heat of crosslinking appear to promote volatilization.

  In the cured film of the curable protective layer in which the retention of residual solvent and curing failure are suppressed to a sufficient extent, no endothermic peak is observed even when a DSC curve is obtained in the same manner as before. Therefore, it is desirable to form a curable protective layer exhibiting this feature.

Next, in the case of the photocuring type, a UV irradiation light source such as a high-pressure mercury lamp or a metal halide lamp mainly having an emission wavelength in ultraviolet light can be used. In addition, a visible light source can be selected in accordance with the absorption wavelength of the radical polymerizable substance or the photopolymerization initiator. Irradiation light amount is 50 mW / cm ² or more, preferably 1000 mW / cm ² or less, it takes time for the curing reaction is less than 50 mW / cm ^2. If it is higher than 1000 mW / cm ^2, the progress of the reaction becomes non-uniform, and local flaws are generated on the surface of the cross-linked charge transport layer, or many unreacted residues and reaction termination ends are generated. In addition, internal stress increases due to rapid crosslinking, which causes cracks and film peeling.

  The thickness of the curable surface layer is suitably about 1 to 10 μm, preferably about 2 to 8 μm.

  Hereinafter, the present invention will be described by way of examples.

  First, the measurement method according to the present invention will be described.

(1) Calculation of adhesion work and surface free energy A fluororesin powder prepared by pressing a fluororesin powder into a disk shape with a pellet tablet machine was prepared as a sample for contact angle measurement. A binder resin mixture dissolved in tetrahydrofuran was applied on an aluminum plate with a doctor blade, and then heated and dried at 150 ° C. for 30 minutes to prepare a sample for contact angle measurement.

  The contact angle of these samples at 55 ° C. was determined using an automatic contact angle meter (CA-W, manufactured by Kyowa Interface Science Co., Ltd.). Ion-exchanged water, methylene iodide, and α-bromonaphthalene were selected as reference standard substances.

  The measured contact angle for each standard substance and the surface free energy value of the standard substance are the data described in Noriaki Kitasaki, Toshio Hata et al., Japan Adhesion Association Paper 8 (3), 131-141 (1972) (Table 1). Was used to calculate the adhesion force between the standard substance and the sample using the following formula 2.

（数２）
Ｗ_{Ｓｏｌｉｄ Ｌｉｑｕｉｄ}＝γ_{Ｌｉｑｕｉｄ}（１＋ｃｏｓθ）
次に、ヨウ化メチレンとα−ブロモナフタレンとサンプルの接着力、および下記数３を用いて連立方程式を立てる。

(Equation 2)
W _{Solid Liquid} = γ _Liquid (1 + cos θ)
Next, simultaneous equations are established using the adhesive strength of methylene iodide, α-bromonaphthalene and the sample, and the following Equation 3.

(Equation 3)



Here, γ ₁ ^a and γ ₁ ^b of the standard materials use the data of the above-mentioned materials.

Now, it was calculated √γ ^a and √γ ^b of the sample.

Next, √γ ^c of the sample was calculated using the adhesive force between water and the photoreceptor and Equation 2.

The surface free energy of the photoconductor was calculated from √γ ^a , √γ ^b , √γ ^{c of the} obtained photoconductor and Equation 3.

(Equation 4)
γ = γ ^a + γ ^b + γ ^c
The adhesive force between the fluororesin and the binder resin was obtained by substituting each numerical value obtained from the above calculation into Equation 3.

(2) Measurement of elastic work ratio From the curve of the photoreceptor load-indentation depth measured with a microhardness tester (FISCHER SCOPE H100C, manufactured by Fischer) under the conditions of a maximum indentation load of 9.8 mN and a creep time of 5 seconds. The elastic power was calculated.

(3) Taber abrasion test A sample with a 10cm square aluminum lithographic plate provided with a charge transport layer and a curable surface layer was prepared, and this was loaded with a load of 1kgf and CS5 wear wheel according to JIS K 5600-5-9: 1999. The weight reduction amount of the sample at 100,000 rotations was weighed.

(4) Photoreceptor rotational force (torque) measurement The rotational force was measured by a unit testing machine (manufactured by Ricoh Co., Ltd.) comprising a motor for driving the photoreceptor, a torque converter, a developing machine, a cleaner, and a programmable logic controller. The unit testing machine is adjusted to the same conditions as a color laser printer (IPSiO Color 8100, Ricoh), and the rotational force (with the photoconductor rotating after the toner has been completely developed on the surface of the photoconductor for two rotations of the drum) ( (Torque) equilibrium value was read.

(5) Film thickness measurement The film thickness was measured at an interval of 1 cm in the longitudinal direction of the photosensitive drum with an eddy current type film thickness measuring instrument (FISCHER SCOPE mms, manufactured by Fischer), and the average value thereof was defined as the photosensitive layer thickness.

(6) Photoconductor surface potential measurement A modified development unit equipped with a probe of a surface potential meter (Trek Model 344, manufactured by Trek) was attached to the developing unit in the copier, and the surface potential at the center of the photoconductor was measured.

  The toners used in Examples and Comparative Examples were prepared based on Japanese Patent Application Laid-Open No. 2003-167384. The polymerizable toner was prepared as follows. In the present invention, this toner is referred to as A toner.

<Synthesis of resin fine particle emulsion>
In a reaction vessel equipped with a stirrer and a thermometer, 683 parts of ion-exchanged water, 11 parts of sodium salt of ethylene oxide methacrylate adduct sulfate (Eleminol RS-30: manufactured by Sanyo Chemical Industries), 83 parts of styrene, 83 parts of methacrylic acid Parts, 110 parts of butyl acrylate, and 1 part of ammonium persulfate were added and stirred at 400 rpm for 15 minutes to obtain a white emulsion. The system was heated to raise the system temperature to 80 ° C. and reacted for 5 hours. Furthermore, 30 parts of a 1% ammonium persulfate aqueous solution was added dropwise, and the mixture was aged at 80 ° C. for 7 hours, followed by vinyl resin (styrene-methacrylic acid-butyl acrylate-methacrylic acid etherene oxide adduct sulfate sodium salt). Polymer) aqueous dispersion [fine particle dispersion 1] was obtained. The volume average particle diameter of the [fine particle dispersion 1] measured by LA-920 was 0.09 μm. A portion of [Fine Particle Dispersion 1] was dried to isolate the resin component. The resin content Tg was 58 ° C.

<Adjustment of aqueous phase>
1000 parts of ion-exchanged water, 83 parts of [fine particle dispersion 2], 37 parts of a 48.5% aqueous solution of sodium dodecyl diphenyl ether disulfonate (Eleminol MON-7: manufactured by Sanyo Chemical Industries) and 90 parts of ethyl acetate are mixed and stirred to give a milky white color Obtained liquid. This is designated as [Aqueous Phase 1].

<Synthesis of low molecular weight polyester>
In a reaction vessel equipped with a condenser, stirrer and nitrogen inlet tube, 229 parts of bisphenol A ethylene oxide 2-mole adduct, 529 parts of bisphenol A propylene oxide 3-mole adduct, 208 parts terephthalic acid, 46 parts adipic acid and dibutyl Add 2 parts of tin oxide, react for 8 hours at 230 ° C. under normal pressure, and further react for 5 hours under reduced pressure of 10 to 15 mmHg. The mixture was reacted for 2 hours to obtain [Low molecular polyester 1]. [Low molecular polyester 1] had a number average molecular weight of 2500, a weight average molecular weight of 6700, a Tg of 43 ° C., and an acid value of 25.

<Synthesis of prepolymer having isocyanate group>
Production Example 13
In a reaction vessel equipped with a condenser, a stirrer and a nitrogen introduction pipe, 682 parts of bisphenol A ethylene oxide 2-mole adduct, 81 parts of bisphenol A propylene oxide 2-mole adduct, 283 parts of terephthalic acid, 22 parts of trimellitic anhydride Then, 2 parts of dibutyltin oxide was added, reacted at 230 ° C. for 8 hours at normal pressure, and further [intermediate polyester 1] reacted for 5 hours at a reduced pressure of 10 to 15 mmHg. [Intermediate Polyester 1] had a number average molecular weight of 2,100, a weight average molecular weight of 9,500, Tg of 55 ° C., an acid value of 0.5, and a hydroxyl value of 51.
Next, 410 parts of [Intermediate Polyester 1], 89 parts of isophorone diisocyanate and 500 parts of ethyl acetate are placed in a reaction vessel equipped with a cooling pipe, a stirrer and a nitrogen introduction pipe, and reacted at 100 ° C. for 5 hours. Polymer 1] was obtained. [Prepolymer 1] had a free isocyanate weight% of 1.53%.

<Synthesis of ketimine>
Production Example 14
In a reaction vessel equipped with a stir bar and a thermometer, 170 parts of isophoronediamine and 75 parts of methyl ethyl ketone were charged and reacted at 50 ° C. for 5 hours to obtain [ketimine compound 1]. The amine value of [ketimine compound 1] was 418.

<Pigment masterbatch adjustment>
Production Example 15
1200 parts of water, 540 parts of carbon black (printex 60 Dexa), 1200 parts of [low molecular weight polyester 1] are added and mixed with a Henschel mixer (made by Mitsui Mining Co., Ltd.), and the mixture is used at 130 ° C. for 45 minutes using two rolls. After kneading, rolling and cooling were performed, and the mixture was pulverized to 1 mmφ or less with a pulverizer to obtain [Master batch 1].

<Creation of oil phase>
In a container equipped with a stirring bar and a thermometer, 378 parts of [Low molecular weight polyester 1], 110 parts of synthetic ester wax, 22 parts of CCA (salicylic acid metal complex E-84: Orient Chemical Industry), and 947 parts of ethyl acetate are charged and stirred. The temperature was raised to 80 ° C., kept at 80 ° C. for 5 hours, and then cooled to 30 ° C. over 1 hour. Next, 500 parts of [Masterbatch 1] and 500 parts of ethyl acetate were charged in a container and mixed for 1 hour to obtain [Raw material solution 1].

  [Raw material solution 1] 1324 parts are transferred to a container, and using a bead mill (Ultra Visco Mill, manufactured by Imex Co., Ltd.), a liquid feeding speed of 1 kg / hr, a disk peripheral speed of 6 m / sec, and 0.5 mm zirconia beads are 80 vol% Carbon black and WAX were dispersed under conditions of filling and 3 passes. Next, 1324 parts of a 65% ethyl acetate solution of [low molecular weight polyester 1] was added, and one pass was performed with a bead mill under the above conditions to obtain [Pigment / WAX Dispersion 1]. The solid content concentration of [Pigment / WAX Dispersion 1] (130 ° C., 30 minutes) was 50%.

<Emulsification → Desolvation>
[Pigment / WAX Dispersion 1] 650 parts, [Prepolymer 1] 140 parts, [Ketimine Compound 1] 6.0 parts are put in a container and TK homomixer (manufactured by Tokushu Kika) at 5,000 rpm for 1 minute. After mixing, 1200 parts of [Aqueous phase 1] was added to the container, and mixed with a TK homomixer at 13,000 rpm for 20 minutes to obtain [Emulsion slurry 1].

  [Emulsion slurry 1] was put into a container equipped with a stirrer and a thermometer, and after removing the solvent at 30 ° C. for 8 hours, aging was carried out at 40 ° C. for 8 hours to obtain [Dispersion slurry 1].

<Washing → Drying>
[Emulsified slurry 1] After 100 parts were filtered under reduced pressure,
(1): 100 parts of ion-exchanged water was added to the filter cake, mixed with a TK homomixer (10 minutes at 12,000 rpm), and then filtered.

(2): 100 parts of a 10% aqueous sodium hydroxide solution was added to the filter cake of (1), mixed with a TK homomixer (30 minutes at 12,000 rpm), and then filtered under reduced pressure.
(3): 100 parts of 10% hydrochloric acid was added to the filter cake of (2), mixed with a TK homomixer (rotation speed: 12,000 rpm for 10 minutes), and then filtered.

  (4): Add 300 parts of ion-exchanged water to the filter cake of (3), mix with a TK homomixer (rotation speed 12,000 rpm for 10 minutes) and then filter twice, and filter cake 1 Obtained.

  [Filter cake 1] was dried with a circulating dryer at 45 ° C. for 48 hours, and sieved with an opening of 75 μm mesh to obtain toner particles 1.

  This toner had a volume average particle size of 5.43 μm, Tg of 46 ° C., and a THF insoluble content of the resin component of 12%. Toner particles 1 were added to 95 parts by weight of a carrier obtained by coating a magnetite powder having an average particle size of 35 μm with methyl methacrylate resin (35% by weight), silicon resin (60% by weight), and carbon (Ketjen Black, 5% by weight). Part by weight was mixed.

[Example 1]
By coating and drying an undercoat layer coating solution, a charge generation layer coating solution, and a charge transport layer coating solution in the following order on a φ30 mm aluminum drum in sequence, an undercoat layer of 3.5 μm, 0 A 2 μm charge generation layer and a 20 μm charge transport layer were formed. A curable surface layer having the following composition was sprayed thereon to cure the curable surface layer, and a 7 μm fluororesin-containing charge transport layer was provided to obtain an electrophotographic photoreceptor.

[Coating liquid for undercoat layer]
Alkyd resin solution (Beckolite M6401-50, manufactured by Dainippon Ink and Chemicals) 12 parts by weight Melamine resin solution (Super Becamine G-821-60, manufactured by Dainippon Ink and Chemicals) 8 parts by weight Titanium oxide (CR- EL Ishihara Sangyo Co., Ltd.) 40 parts by weight methyl ethyl ketone 200 parts by weight [charge generation layer coating solution]
5 parts by weight of bisazo pigment having the following structure (manufactured by Ricoh)

ポリビニルブチラール（ＸＹＨＬ、ＵＣＣ社製） １重量部
シクロヘキサノン ２００重量部
メチルエチルケトン ８０重量部
〔電荷輸送層用塗工液〕
Ｚ型ポリカーボネート（パンライトＴＳ−２０５０、帝人化成社製） ９重量部
下記構造の低分子電荷輸送物質 ８重量部

Polyvinyl butyral (XYHL, manufactured by UCC) 1 part by weight Cyclohexanone 200 parts by weight Methyl ethyl ketone 80 parts by weight [Coating liquid for charge transport layer]
Z-type polycarbonate (Panlite TS-2050, manufactured by Teijin Chemicals Ltd.) 9 parts by weight 8 parts by weight of low molecular charge transport material having the following structure

テトラヒドロフラン １００重量部
１％シリコーンオイル（ＫＦ５０−１００ＣＳ信越化学工業社製）テトラヒドロフラン溶液 １重量部
〔硬化型表面層塗工液〕
下記構造の硬化性電荷輸送物質 ３０重量部

Tetrahydrofuran 100 parts by weight 1% silicone oil (KF50-100CS manufactured by Shin-Etsu Chemical Co., Ltd.) Tetrahydrofuran solution 1 part by weight [Curing type surface layer coating solution]
30 parts by weight of curable charge transport material having the following structure

自己治癒性クリヤーＮｏ．１００（主剤）、ナトコ社 ２７．７重量部
熱硬化性疎水性樹脂、ＺＸ−００７Ｃ、富士化成工業社 ５重量部（固形分重量）
ＨＤＩ系ポリイソシアネート、コロネートＨＸ、日本ポリウレタン社 ３７．３重量部
１−メトキシ−２プロパノール ９００重量部
［実施例２］
実施例１における硬化性表面層用塗工液を以下のものに変更した以外は実施例１と同様にして電子写真感光体を得た。

Self-healing clear no. 100 (main agent), NATCO 27.7 parts by weight Thermosetting hydrophobic resin, ZX-007C, Fuji Chemical Industry Co., Ltd. 5 parts by weight (solid content weight)
HDI polyisocyanate, Coronate HX, Nippon Polyurethane 37.3 parts by weight 1-methoxy-2-propanol 900 parts by weight [Example 2]
An electrophotographic photosensitive member was obtained in the same manner as in Example 1 except that the curable surface layer coating solution in Example 1 was changed to the following.

[Curing surface layer coating solution]
30 parts by weight of curable charge transport material having the following structure

自己治癒性クリヤーＮｏ．１００（主剤）、ナトコ社 ２７．７重量部
熱硬化性フッ素系界面活性剤、モディパーＦ２００、日本油脂社 ２．５重量部（固形分重量）
熱硬化性シリコーン、サイマック ＵＳ−３８０、東亜合成社 ２．５重量部（固形分重量）
ＨＤＩ系ポリイソシアネート、コロネートＨＸ、日本ポリウレタン社 ３７．３重量部
１−メトキシ−２プロパノール ９００重量部
［比較例１］
実施例１における硬化性表面層用塗工液を以下のものに変更した以外は実施例１と同様にして電子写真感光体を得た。

Self-healing clear no. 100 (main agent), 27.7 parts by weight of Natco Co., Ltd. Thermosetting fluorosurfactant, Modiper F200, 2.5 parts by weight of NOF Corporation (solid weight)
Thermosetting silicone, Cymac US-380, Toa Gosei Co., Ltd. 2.5 parts by weight (solid content weight)
HDI polyisocyanate, Coronate HX, Nippon Polyurethane 37.3 parts by weight 1-methoxy-2-propanol 900 parts by weight [Comparative Example 1]
An electrophotographic photosensitive member was obtained in the same manner as in Example 1 except that the curable surface layer coating solution in Example 1 was changed to the following.

[Curing surface layer coating solution]
30 parts by weight of curable charge transport material having the following structure

自己治癒性クリヤーＮｏ．１００（主剤）、ナトコ社 ２７．７重量部
熱硬化性フッ素系界面活性剤、モディパーＦ２００、日本油脂社 ５重量部（固形分重量）
ＨＤＩ系ポリイソシアネート、コロネートＨＸ、日本ポリウレタン社 ３７．３重量部
１−メトキシ−２プロパノール ９００重量部
［比較例２］
実施例１における硬化性表面層用塗工液を以下のものに変更した以外は実施例１と同様にして電子写真感光体を得た。

Self-healing clear no. 100 (main agent), 27.7 parts by weight of Natco Co., Ltd. Thermosetting fluorosurfactant, Modiper F200, 5 parts by weight of NOF Corporation (solid weight)
HDI polyisocyanate, Coronate HX, Nippon Polyurethane 37.3 parts by weight 1-methoxy-2-propanol 900 parts by weight [Comparative Example 2]
An electrophotographic photosensitive member was obtained in the same manner as in Example 1 except that the curable surface layer coating solution in Example 1 was changed to the following.

[Curing surface layer coating solution]
30 parts by weight of curable charge transport material having the following structure

自己治癒性クリヤーＮｏ．１００（主剤）、ナトコ社 ２７．７重量部
熱硬化性シリコーン、サイマック ＵＳ−３８０、東亜合成社 ２．５重量部（固形分重量）
ＨＤＩ系ポリイソシアネート、コロネートＨＸ、日本ポリウレタン社 ３７．３重量部
１−メトキシ−２プロパノール ９００重量部
［比較例３］
実施例１における硬化性表面層用塗工液を以下のものに変更した以外は実施例１と同様にして電子写真感光体を得た。

Self-healing clear no. 100 (main agent), Natoko 27.7 parts by weight Thermosetting silicone, Cymac US-380, Toa Gosei Co., Ltd. 2.5 parts by weight (solid content weight)
HDI-based polyisocyanate, Coronate HX, Nippon Polyurethane 37.3 parts by weight 1-methoxy-2-propanol 900 parts by weight [Comparative Example 3]
An electrophotographic photosensitive member was obtained in the same manner as in Example 1 except that the curable surface layer coating solution in Example 1 was changed to the following.

[Coating liquid for protective layer]
Fluororesin particles (MPE-056, manufactured by Mitsui DuPont Fluorochemical Co., Ltd.) 55 parts by weight Fluorosurfactant (Modiper F210, manufactured by NOF Corporation) 10 parts by weight (solid content: 3 parts by weight)
Polycarbonate (Z polycarbonate, viscosity average molecular weight; 50,000, manufactured by Teijin Chemicals Ltd.) 42 parts by weight Tetrahydrofuran 2500 parts by weight Cyclohexanone 700 parts by weight [Comparative Example 4]
An electrophotographic photosensitive member was obtained in the same manner as in Example 1 except that the curable surface layer coating solution in Example 1 was changed to the following.

[Curing surface layer coating solution]
30 parts by weight of curable charge transport material having the following structure

自己治癒性クリヤーＮｏ．１００（主剤）、ナトコ社 ３０重量部
ＨＤＩ系ポリイソシアネート、コロネートＨＸ、日本ポリウレタン社 ４０重量部
１−メトキシ−２プロパノール ９００重量部
以上のように作製した実施例１〜実施例３と比較例１〜４の電子写真感光体を実装用にした後、電子写真装置（リコー社製：Ｉｍａｇｉｏ Ｎｅｏ Ｃ６００）に搭載し、画素密度が６００ｄｐｉ×６００ｄｐｉで画像濃度が５％となるテキストとグラフィック画像のパターンを連続５枚づつ印刷する条件で、通算４万枚、コピー用紙（リコー社製ＴＹＰＥ６０００）にプリントアウトした。

Self-healing clear no. 100 (main agent), Natoko 30 parts by weight HDI polyisocyanate, Coronate HX, Nippon Polyurethanes 40 parts by weight 1-methoxy-2-propanol 900 parts by weight Examples 1 to 3 and Comparative Example 1 prepared as described above A pattern of text and graphic images in which an electrophotographic photosensitive member of 4 to 4 is mounted for mounting and then mounted on an electrophotographic apparatus (manufactured by Ricoh: Image Neo Neo C600), with a pixel density of 600 dpi × 600 dpi and an image density of 5%. Were printed out on copy paper (TYPE6000 manufactured by Ricoh) under the condition of printing 5 sheets continuously.

  As the toner, the aforementioned A toner was used. As the developer carrier, a silicone-coated ferrite carrier having an average particle size of 40 μm was used. 280 g of a mixture of ferrite carrier and A toner having a toner content of 5 wt% was used as a developer carrier in each color developing station unit.

  As the charging means of the electrophotographic apparatus, a charging roller disposed in proximity to the electrophotographic photosensitive member was used. The fixing temperature was set to 120 ° C. The use of A toner was able to fix without problems.

  As the applied voltage of the charging roller, a peak-to-peak voltage of 1.5 kV and a frequency of 0.9 kHz were selected as AC components. For the DC component, a bias was set so that the charged potential of the photosensitive member at the start of the test was −700 V, and the test was performed under this charging condition until the end of the test. The developing bias was −500V. In this apparatus, no neutralizing means is provided. The cleaning means used was genuine.

  The test environment was 24 ° C./54% RH.

  At the end of the test, 10 halftone images having a pixel density of 1200 dpi × 1200 dpi and an image density of 5% were continuously printed out. Next, the surface of the photosensitive member passing through the cleaning blade was observed with a microscope, and the quality of the cleaning was judged in five stages. Further, the abrasion amount of the photoconductor by the test was measured. The test results are shown in Table 2. In addition, the measured values of the toner photoconductor surface interlayer adhesion work, photoconductor rotating force (torque), Taber abrasion amount, and elastic work rate measured before and after the test are also described.

試験前後の接着仕事が小さい実施例１と２および比較例３は低温定着用のトナーを使用しても トナーのフィルミングは見られなかった。但し、比較例３は激しい膜削れを来した。他方、実施例１と実施例２では膜削れが格段に小さい。また、比較例１、比較例２は感光体表面に潤滑剤が配合されているもののクリーニング性は十分とは言えない。これらはクリーニングブレードの欠けが見られこれがクリーニング性に影響したと考えられる。

In Examples 1 and 2 and Comparative Example 3 in which the adhesion work before and after the test was small, no toner filming was observed even when a low-temperature fixing toner was used. However, Comparative Example 3 caused severe film scraping. On the other hand, in Example 1 and Example 2, film abrasion is remarkably small. In Comparative Examples 1 and 2, although the lubricant is blended on the surface of the photoreceptor, the cleaning property is not sufficient. In these cases, the cleaning blade was chipped, which was considered to have affected the cleaning performance.

[Example 3]
By coating and drying an undercoat layer coating solution, a charge generation layer coating solution, and a charge transport layer coating solution on a 0.8 mm thick aluminum drum of the following composition in order, 3.5 μm An undercoat layer, a 0.2 μm charge generation layer, and a 29 μm charge transport layer were formed. Next, a coating solution for the outermost surface layer of the photoconductor was applied by ring coating, the curable surface layer was cured, and an outermost surface layer of 5 μm was provided to obtain the electrophotographic photoconductor of the present invention.

[Coating liquid for undercoat layer]
Alkyd resin (Beccosol 1307-60-EL, manufactured by Dainippon Ink and Chemicals) 12 parts by weight Melamine resin (Super Becamine G-821-60, manufactured by Dainippon Ink and Chemicals) 8 parts by weight
CR-EL Ishihara Sangyo Co., Ltd.) 40 parts by weight Methyl ethyl ketone 200 parts by weight [Coating liquid for charge generation layer]
Titanyl phthalocyanine (manufactured by Ricoh) 20 parts by weight Polyvinyl alcohol (ESREC B BX-1, Sekisui Chemical Co., Ltd.) 10 parts by weight Methyl ethyl ketone 100 parts by weight [Coating liquid for charge transport layer]
Polycarbonate resin (Panlite TS-2050, manufactured by Teijin Chemicals Ltd.) 7 parts by weight 10 parts by weight of low molecular charge transport material having the following structure

テトラヒドロフラン ７９重量部
１％シリコーンオイル（ＫＦ５０−１００ＣＳ信越化学工業社製）テトラヒドロフラン溶液 １重量部
〔硬化型表面層用塗工液〕
下記構造の硬化性電荷輸送物質 ４２．５重量部

Tetrahydrofuran 79 parts by weight 1% silicone oil (KF50-100CS manufactured by Shin-Etsu Chemical Co., Ltd.) Tetrahydrofuran solution 1 part by weight [Curing type surface layer coating solution]
42.5 parts by weight of curable charge transport material having the following structure

ラジカル重合性疎水性樹脂（ＺＸ−０２２−Ｕ、富士化成工業社） ５重量部
トリメチロールプロパントリアクリレート ２１．２５重量部
カプロラクトン変性ジペンタエリスリトールヘキサアクリレート（ＫＡＹＡＲＤ ＤＰＣＡ−１２０、日本化薬社） ２１．２５重量部
開始剤（イルガキュア１８４、チバ・スペシャリティーケミカルズ社） ３重量部
テトラヒドロフラン ６６７重量部
［比較例５］
実施例３における硬化性表面層用塗工液を以下のものに変更した以外は実施例３と同様にして電子写真感光体を得た。

Radical polymerizable hydrophobic resin (ZX-022-U, Fuji Kasei Kogyo Co., Ltd.) 5 parts by weight Trimethylolpropane triacrylate 21.25 parts by weight Caprolactone-modified dipentaerythritol hexaacrylate (KAYARD DPCA-120, Nippon Kayaku Co., Ltd.) 21 .25 parts by weight Initiator (Irgacure 184, Ciba Specialty Chemicals) 3 parts by weight Tetrahydrofuran 667 parts by weight [Comparative Example 5]
An electrophotographic photosensitive member was obtained in the same manner as in Example 3 except that the curable surface layer coating solution in Example 3 was changed to the following.

[Curing type surface layer coating solution]
45 parts by weight of curable charge transport material having the following structure

トリメチロールプロパントリアクリレート ２２．５重量部
カプロラクトン変性ジペンタエリスリトールヘキサアクリレート（ＫＡＹＡＲＤ ＤＰＣＡ−１２０、日本化薬社） ２２．５重量部
開始剤（イルガキュア１８４、チバ・スペシャリティーケミカルズ社） ３重量部
テトラヒドロフラン ６６７重量部
以上のように作製した実施例４と比較例５の電子写真感光体を実装用にした後、電子写真装置（リコー社製：Ｉｍａｇｉｏ Ｎｅｏ １０５０Ｐｒｏ）に搭載し、画素密度が６００ｄｐｉ×６００ｄｐｉで画像濃度が５％となるテキストとグラフィック画像のパターンを連続５枚づつ印刷する条件で、通算４万枚、コピー用紙（リコー社製ＴＹＰＥ６０００）にプリントアウトした。

Trimethylolpropane triacrylate 22.5 parts by weight Caprolactone-modified dipentaerythritol hexaacrylate (KAYARD DPCA-120, Nippon Kayaku) 22.5 parts by weight Initiator (Irgacure 184, Ciba Specialty Chemicals) 3 parts by weight Tetrahydrofuran 667 parts by weight After the electrophotographic photoreceptors of Example 4 and Comparative Example 5 produced as described above were used for mounting, they were mounted on an electrophotographic apparatus (manufactured by Ricoh: Image Neo Neo 1050Pro), and the pixel density was 600 dpi × 600 dpi. Then, text and graphic image patterns with an image density of 5% were printed on copy paper (type 6000 manufactured by Ricoh Co., Ltd.) for a total of 40,000 sheets under the condition of printing five consecutive images.

  As the toner, the aforementioned A toner was used. As the developer carrier, a silicone-coated ferrite carrier having an average particle size of 40 μm was used. 280 g of a mixture of ferrite carrier and A toner having a toner content of 5 wt% was used as a developer carrier in each color developing station unit.

  As the charging means of the electrophotographic apparatus, a charging roller disposed in proximity to the electrophotographic photosensitive member was used. The fixing temperature was set to 120 ° C. The use of A toner was able to fix without problems.

  The bias roller was set to a bias such that the charging potential of the photosensitive member at the start of the test was −800 V, and the test was performed under this charging condition until the end of the test. The developing bias was −550V. The genuine cleaning means was used as it was.

  The test environment was 24 ° C./54% RH.

  At the end of the test, 10 halftone images having a pixel density of 1200 dpi × 1200 dpi and an image density of 5% were continuously printed out. Next, the surface of the photosensitive member passing through the cleaning blade was observed with a microscope, and the quality of the cleaning was judged in five stages. Further, the abrasion amount of the photoconductor by the test was measured. The test results are shown in Table 2. In addition, the measured values of toner photoreceptor surface interlayer adhesion work, photoreceptor rotational force (torque), Taber abrasion amount, and elastic work rate measured before and after the test are also described.

光硬化タイプの硬化型表面層に対しても実施例 １と同様にクリーニング性に優れる結果を得た。ラジカル重合性疎水性樹脂がクリーニング性向上に作用したと考えられる。

Similar to Example 1, the result of excellent cleaning performance was obtained for the photocuring type curable surface layer. The radical polymerizable hydrophobic resin is considered to have improved the cleaning property.

  As described above, the electrophotographic photosensitive member of the present invention is not only excellent in abrasion resistance but also exhibits properties that are not accompanied by filming when the toner for low-temperature fixing is used. It is a photoconductor with a high contribution to energy saving that can realize the low-temperature fixing of electrophotographic apparatus.

  Although the embodiments and examples of the present invention have been specifically described above, the present invention is not limited to these embodiments and examples, and these embodiments and examples of the present invention are not limited thereto. Can be changed or modified without departing from the spirit and scope of the present invention.

  INDUSTRIAL APPLICABILITY The present invention can be applied to an electrophotographic photosensitive member having a curable protective layer laminated on the surface, a manufacturing method thereof, an electrophotographic apparatus, or a process cartridge that can be attached to and detached from the electrophotographic apparatus. In particular, the present invention provides an electrophotographic photoreceptor capable of saving resources and improving energy saving of an electrophotographic apparatus, an abrasion-resistant organic electrophotographic photoreceptor capable of preventing contamination of low-temperature fixing toner, and a method for producing the same. The present invention can be suitably applied to providing an electrophotographic apparatus having high energy saving performance.

1 is a schematic sectional view showing an example of an electrophotographic apparatus according to the present invention. It is sectional drawing which shows the layer structure of the electrophotographic photoreceptor which concerns on this invention. It is sectional drawing which shows another layer structure of the electrophotographic photoreceptor which concerns on this invention.

Explanation of symbols

(About Figure 1)
DESCRIPTION OF SYMBOLS 11 ... Electrophotographic photoreceptor 12 ... Charging means 13 ... Exposure means 14 ... Developing means 15 ... Toner 16 ... Transfer means 17 ... Cleaning means 18 ... Image receiving medium 19 ... Fixing means 1A ... Charging means 1B ... Pre-cleaning exposure means 1C ... Drive means 1D ... First transfer means 1E ... Second transfer means 1F ... Intermediate transfer member 1G: Image receiving medium carrier (about FIGS. 2 and 3)
21 ... conductive support 22 ... undercoat layer 25 ... charge generation layer 26 ... charge transport layer 28 ... body outermost surface layer

Claims (14)

In an organic electrophotographic photoreceptor in which a curable surface layer is laminated,
An electrophotographic photosensitive member comprising a curable charge transporting component, a curable binder component, a curable fluororesin component, and a polysiloxane component in the surface layer.   2. The electrophotographic photoreceptor according to claim 1, wherein the curable fluororesin component and the polysiloxane component are a curable fluororesin / siloxane graft polymer.   The curable fluororesin / siloxane graft polymer is an organic solvent-soluble fluororesin component (A) having a radically polymerizable unsaturated bond moiety through at least a urethane bond, a single-end radical polymerizable polysiloxane component (B), and a single-end 3. The electrophotographic photoreceptor according to claim 2, which is a graft copolymer of radically polymerizable alkoxy polyalkylene glycol (C).   Organic solvent-soluble fluororesin component (A), radically polymerizable polysiloxane component (B) having one terminal end and radical polymerization in which the curable fluororesin / siloxane graft polymer has a radically polymerizable unsaturated bond moiety via at least a urethane bond, and radical polymerization Under the reaction conditions, the graft copolymer of the radically polymerizable monomer that does not react other than the polymerization reaction by the double bond with the organic solvent-soluble fluororesin (A) having a radically polymerizable unsaturated bond moiety through the urethane bond. The electrophotographic photosensitive member according to claim 2, which is a polymer. The one-end radical polymerizable polysiloxane is represented by the following general formula (1):

(In the formula, R1 is a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms, and R2, R3, R4, R5, and R6 may be the same or different from each other, and may be the same or different from each other. And n is an integer of 2 or more) and / or a radically polymerizable polysiloxane having one terminal and / or the following general formula (2)

(In the formula, R7 is a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms, and R8, R9, R10, R11, and R12 may be the same as or different from each other, and may be the same or different from each other. 4 to 40% by weight of a single-end radical polymerizable polysiloxane represented by the following formula: wherein p is an integer of 0 to 10 and q is an integer of 2 or more. The electrophotographic photosensitive member according to 3 or 4. The one-end radical polymerizable alkoxy polyalkylene glycol is represented by the following general formula (3):

(In the formula, R13 is a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms, R14 is a hydrocarbon group having 1 to 10 carbon atoms, and R15 is a straight chain having 1 to 10 carbon atoms. Or a hydrocarbon group which may be substituted with a branched halogen atom, l is an integer of 1 or more, and m is an arbitrary integer). 25% by weight and (D) a graft copolymer obtained by random copolymerization of 28 to 92% by weight of radically polymerizable monomers other than components (A), (B), and (C) The electrophotographic photosensitive member according to claim 3.   The organic solvent-soluble fluororesin (A) having a radical polymerizable unsaturated bond moiety via the urethane bond is composed of an organic solvent-soluble fluororesin (A-1) having a hydroxyl group and a radical polymerizable monomer having an isocyanate group ( The electrophotographic photosensitive member according to any one of claims 3 to 6, which is a reaction product with A-2).   The radically polymerizable monomer (A-2) having the isocyanate group is selected from methacryloyl isocyanate, 2-isocyanatoethyl methacrylate, or m- or p-isopropenyl-α, α-dimethylbenzyl isocyanate. The electrophotographic photosensitive member according to any one of claims 3 to 6, wherein the electrophotographic photosensitive member is one type or two or more types. The curable charge transport component is represented by the following general formula (4)

Represents. The electrophotographic photosensitive member according to any one of claims 1 to 8, wherein the electrophotographic photosensitive member is a radically polymerizable monomer. A radical polymerizable compound having a monofunctional charge transport structure used in the cross-linked charge transport layer is represented by the following general formula (4).

Represents. The electrophotographic photoreceptor according to any one of claims 1 to 8, wherein the electrophotographic photoreceptor is one or more of radically polymerizable monomers.   The electron according to any one of claims 1 to 10, wherein the curable binder component is at least one of trimethylolpropane triacrylate, caprolactone-modified dipentaerythritol hexaacrylate, and dipentaerythritol hexaacrylate. Photoconductor.   When the elastic power of the curable surface layer is 50% or more and the wear amount of CS5 is 1.5 mg / 10,000 rotations or less, the surface layer and the toner at the surface layer temperature in the electrophotographic apparatus before and after use of the electrophotographic apparatus 12. The electrophotographic photosensitive member according to claim 9, wherein the adhesion work is 20 mN / m or more and 75 mN / m or less and the rotational force (torque) for driving the photosensitive member is 2.5 kgfcm or less. .   A process cartridge on which the electrophotographic photosensitive member according to any one of claims 1 to 12 is mounted. The electrophotographic photosensitive member according to any one of claims 1 to 12 or the process cartridge according to claim 13 is mounted, a drum heater is not provided, and a toner fixing temperature is less than 120 ° C. A feature of an electrophotographic apparatus.

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