JP2011164280A - Electrophotographic photoreceptor, and electrophotography, electrophotographic device and process cartridge for electrophotographic device using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electrophotographic photoreceptor having a coating layer, containing a new methylol compound excelling in solubility with a solvent and compatibility with a binder resin and excelling in both the electrical characteristics and the durability. <P>SOLUTION: The electrophotographic photoreceptor has a photosensitive layer, containing a methylol compound represented by general the formula (1) on a conductive support, wherein X represents -O-, -CH<SB>2</SB>-, -CH=CH- or -CH<SB>2</SB>CH<SB>2</SB>-. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an electrophotographic photoreceptor in which at least one specific methylol compound is contained in a photosensitive layer, and to an electrophotographic method, an electrophotographic apparatus, and an electrophotographic process cartridge using the electrophotographic photoreceptor.

  In recent years, there has been a remarkable development in information processing system machines using electrophotography. In particular, laser printers and digital copying machines that convert information into digital signals and record information using light have significantly improved print quality and reliability. Furthermore, they have been applied to laser printers or digital copiers capable of full-color printing by fusing with high-speed technology. From such a background, it is particularly important to achieve both high image quality and high durability as a required photoreceptor function.

  As photoconductors used in these electrophotographic laser printers, digital copiers, etc., those using organic photosensitive materials (OPC) are generally widely used for reasons such as cost, productivity and non-pollution. Applied. The layer structure of the OPC photoreceptor is roughly divided into a single layer type and a function separation type laminated structure. The first practical OPC, the PVK-TNF charge transfer complex type photoreceptor, was the former single layer type. On the other hand, in 1968, Hayashi and Regensburger independently invented a PVK / a-Se laminated photoreceptor, and later in 1977 by Melz et al. And in 1978 Schlosser called an organic pigment dispersion layer and an organic low molecular dispersion polymer layer. A multi-layer photoconductor in which all photosensitive layers are made of organic materials has been announced. These are functionally separated from the concept of a charge generation layer (CGL) that absorbs light and generates charges, and a charge transport layer (CTL) that injects and transports charges generated by CGL and neutralizes surface charges. Also called a mold-laminated photoconductor. This development has dramatically improved sensitivity and durability compared to single-layer photoconductors. In addition, since materials having different functions, which are called charge generation materials (CGM) and charge transport materials (CTM), can be individually designed, the selection range of these materials has been greatly increased. For these reasons, the function-separated laminated photoconductor has the mainstream layer structure of the current OPC photoconductor. The mechanism of electrostatic latent image formation in the function-separated type photoconductor is that when the photoconductor is charged and then irradiated with light, the light passes through the charge transport layer and is absorbed by the charge generation material in the charge generation layer to generate a charge. . Charges generated thereby are injected into the charge transport layer at the interface between the charge generation layer and the charge transport layer, and further moved through the charge transport layer by an electric field, thereby forming an electrostatic latent image by canceling the surface charge of the photoreceptor. Is.

In recent years, due to the reduction in the diameter of the photosensitive member accompanying the increase in the speed of the electrophotographic apparatus or the downsizing of the apparatus, the high-speed response and stability of the photosensitive member have become even more important issues.
As commercialized charge transport materials, 1,1-bis (p-diethylaminophenyl) -4,4-diphenyl-1,3-butadiene (Japanese Patent Laid-Open No. 62-30255 of Patent Document 1), 5 -[4- (N, N-di-p-tolylamino) benzylidene] -5H-dibenzo [a, d] cycloheptene (Japanese Patent Application Laid-Open No. 63-225660), 9-methylcarbazole-3-aldehyde 1,1-diphenylhydrazone, pyrene-1-aldehyde 1,1-diphenylhydrazone (Japanese Patent Laid-Open No. 58-159536), 4′-bis (4-methylphenyl) amino-α-phenylstilbene, N, N′-diphenyl-N, N′-bis (3-methylphenyl)-[1,1′-biphenyl] -4,4′-diamine, 9,9-dimethyl-2- (di p- tolylamino), and the like fluorene.
A general charge transport layer is a solid solution film of about 10 to 30 μm in which these low molecular charge transport materials are molecularly dispersed in a binder resin. As the binder resin, bisphenol-based polycarbonate resin, polyarylate resin, or a copolymer of these with other resins is used in most electrophotographic photoreceptors. However, these charge transport materials are not responsive enough to accommodate future faster process speeds.

  On the other hand, Non-Patent Document 1, Journal of Electrophotographic Society, 25 (3), 16 (1986) shows molecular design guidelines regarding the high-speed response (high mobility) of these charge transport materials. That is, a phenylamine group (> N-phenyl) is used as a sensitive group, and this number and mobility are clearly correlated, and it is stated that the higher the number of sensitive groups in the molecule, the higher the mobility. Based on these, the compound in the present invention has a high-sensitivity by having a multi-sensitive group. In addition, by having a methylol group, it is excellent in solubility in a solvent, is excellent in compatibility with a binder resin such as a polycarbonate resin, and further has low crystallinity of the charge transporting substance itself, so that a coating film and a coating can be applied. Excellent liquid stability.

  An object of the present invention is to provide an electrophotographic photosensitive member which is excellent in solubility in a solvent and compatibility with a binder resin, and which is excellent in both electrical characteristics and durability. In addition, by using these photoconductors, it is not necessary to replace the photoconductors, and it is possible to reduce the size of the apparatus accompanying high-speed printing or reducing the diameter of the photoconductor. An electrophotographic method, an electrophotographic apparatus, and an electrophotographic process cartridge are provided.

The above problems are solved by the present invention described below.
(1) An electrophotographic photosensitive member, wherein a photosensitive layer containing a methylol compound represented by the following general formula (1) is provided on a conductive support.

（式中、Ｘは−Ｏ−、−ＣＨ_２−、−ＣＨ＝ＣＨ−、−ＣＨ_２ＣＨ_２−を表す。）」、
（２）「下記一般式（１）で表されるメチロール化合物と、電荷輸送物質とを含有する感光層が、導電性支持体上に設けられていることを特徴とする電子写真感光体。

(Wherein X represents —O—, —CH ₂ —, —CH═CH—, —CH ₂ CH ₂ —) ”,
(2) An electrophotographic photosensitive member, wherein a photosensitive layer containing a methylol compound represented by the following general formula (1) and a charge transporting material is provided on a conductive support.

（式中、Ｘは−Ｏ−、−ＣＨ_２−、−ＣＨ＝ＣＨ−、−ＣＨ_２ＣＨ_２−を表す。）」、
（３）「前記電荷輸送物質が下記一般式（２）で表されるスチルベン化合物であることを特徴とする前記第（２）項に記載の電子写真感光体。

(Wherein X represents —O—, —CH ₂ —, —CH═CH—, —CH ₂ CH ₂ —) ”,
(3) “The electrophotographic photosensitive member according to item (2), wherein the charge transporting substance is a stilbene compound represented by the following general formula (2):

（式中、ｎは０または１の整数、Ｒ^１は水素原子、アルキル基または置換もしくは無置換のフェニル基を表し、Ａｒ^１は置換もしくは無置換の芳香族炭化水素基を表し、Ｒ^５は炭素数１〜４アルキル基、あるいは置換もしくは無置換の芳香族炭化水素基を表し、Ａｒ^１とＲ^５は共同で環を形成しても良い。Ａは

(Wherein n represents an integer of 0 or 1, R ¹ represents a hydrogen atom, an alkyl group or a substituted or unsubstituted phenyl group, Ar ¹ represents a substituted or unsubstituted aromatic hydrocarbon group, and R ⁵ represents It represents a C 1-4 alkyl group, or a substituted or unsubstituted aromatic hydrocarbon group, and Ar ¹ and R ⁵ may form a ring together.

９−アントリル基または置換もしくは無置換のカルバゾリル基を表し、ここでＲ^２は水素原子、アルキル基、アルコキシ基、ハロゲン原子または

Represents a 9-anthryl group or a substituted or unsubstituted carbazolyl group, wherein R ² represents a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom or

（ただし、Ｒ^３およびＲ^４は置換もしくは無置換の芳香族炭化水素基を示し、Ｒ^３およびＲ^４は同じでも異なっていてもよく、環を形成しても良い）を表し、ｍは１〜３の整数を表し、２以上の時Ｒ^２は同一でも異なっても良い。また、ｎが０の時、ＡとＲ^１は共同で環を形成しても良い。）」、
（４）「前記電荷輸送物質が下記一般式（３）で表されるアミノビフェニル化合物であることを特徴とする前記第（２）項に記載の電子写真感光体。

Wherein R ³ and R ⁴ represent a substituted or unsubstituted aromatic hydrocarbon group, R ³ and R ⁴ may be the same or different and may form a ring, and m represents 1 Represents an integer of ˜3, and when 2 or more, R ² may be the same or different. When n is 0, A and R ¹ may form a ring together. ) ",
(4) The electrophotographic photosensitive member according to item (2), wherein the charge transport material is an aminobiphenyl compound represented by the following general formula (3).

（式中、Ｒ^６、Ｒ^８およびＲ^９は水素原子、アミノ基、アルコキシ基、チオアルコキシ基、アリールオキシ基、メチレンジオキシ基、置換もしくは無置換のアルキル基、ハロゲン原子または置換もしくは無置換のアリール基を、Ｒ^７は水素原子、アルコキシ基、置換もしくは無置換のアルキル基またはハロゲン原子を表す。また、ｋ，ｌ，ｍおよびｎは１、２、３または４の整数であり、それぞれが２、３または４の整数の時は、前記Ｒ^６、Ｒ^７、Ｒ^８およびＲ^９は同じでも異なっていても良い。）」、
（５）「前記電荷輸送物質が、高分子型電荷輸送物質であることを特徴とする前記第（２）項に記載の電子写真感光体」、
（６）「前記高分子型電荷輸送物質が下記一般式（４）で表される物質であることを特徴とする前記第（５）項に記載の電子写真感光体。

(Wherein R ⁶ , R ⁸ and R ⁹ are a hydrogen atom, an amino group, an alkoxy group, a thioalkoxy group, an aryloxy group, a methylenedioxy group, a substituted or unsubstituted alkyl group, a halogen atom, or a substituted or unsubstituted group. R ⁷ represents a hydrogen atom, an alkoxy group, a substituted or unsubstituted alkyl group or a halogen atom, and k, l, m and n are integers of 1, 2, 3 or 4, When R is an integer of 2, 3 or 4, the R ⁶ , R ⁷ , R ⁸ and R ⁹ may be the same or different.
(5) "The electrophotographic photosensitive member according to (2) above, wherein the charge transporting material is a polymer type charge transporting material",
(6) “The electrophotographic photosensitive member according to item (5), wherein the polymer charge transporting material is a material represented by the following general formula (4):

（式中、Ｒ_１７，Ｒ_１８は置換もしくは無置換の芳香環基、Ａｒ_１，Ａｒ_２，Ａｒ_３は同一あるいは異なる芳香環基を表す。ｋ，ｊは組成を表し、０．１≦ｋ≦１、０≦ｊ≦０．９、ｎは繰り返し単位数を表し５〜５０００の整数である。Ｘは脂肪族の２価基、環状脂肪族の２価基、または下記一般式で表される２価基を表す。）

(Wherein R ₁₇ and R ₁₈ represent substituted or unsubstituted aromatic ring groups, Ar ₁ , Ar ₂ and Ar ₃ represent the same or different aromatic ring groups. K and j represent compositions, and 0.1 ≦ k ≦ 1, 0 ≦ j ≦ 0.9, n represents the number of repeating units and is an integer of 5 to 5000. X is represented by an aliphatic divalent group, a cycloaliphatic divalent group, or the following general formula. Represents a divalent group.)

（式中、Ｒ_１０１，Ｒ_１０２は各々独立して置換もしくは無置換のアルキル基、芳香環基またはハロゲン原子を表す。ｌ、ｍは０〜４の整数、Ｙは単結合、炭素原子数１〜１２の直鎖状、分岐状もしくは環状のアルキレン基、−Ｏ−，−Ｓ−，−ＳＯ−，−ＳＯ_２−，−ＣＯ−，−ＣＯ−Ｏ−Ｚ−Ｏ−ＣＯ−（式中Ｚは脂肪族の２価基を表す。）または、

(In the formula, R ₁₀₁ and R ₁₀₂ each independently represents a substituted or unsubstituted alkyl group, an aromatic ring group or a halogen atom. L and m are integers of 0 to 4, Y is a single bond and 1 carbon atom. To 12 linear, branched or cyclic alkylene groups, —O—, —S—, —SO—, —SO ₂ —, —CO—, —CO—O—Z—O—CO— Z represents an aliphatic divalent group) or

（式中、ａは１〜２０の整数、ｂは１〜２０００の整数、Ｒ_１０３、Ｒ_１０４は置換または無置換のアルキル基又はアリール基を表す。）を表す。ここで、Ｒ_１０１とＲ_１０２，Ｒ_１０３とＲ_１０４は、それぞれ同一でも異なってもよい。）」、
（７）「前記高分子型電荷輸送物質が下記一般式（５）で表される物質であることを特徴とする電子写真感光体。

(Wherein, a represents an integer of 1 to 20, b represents an integer of 1 to 2000, R ₁₀₃ and R ₁₀₄ represent a substituted or unsubstituted alkyl group or aryl group). Here, R ₁₀₁ and R ₁₀₂ , R ₁₀₃ and R ₁₀₄ may be the same or different. ) ",
(7) “An electrophotographic photoreceptor, wherein the polymer charge transporting material is a material represented by the following general formula (5):

（式中、Ａｒ_４、Ａｒ_５、Ａｒ_６、Ａｒ_７およびＡｒ_８は置換もしくは無置換の芳香環基、Ｚは芳香環基または―Ａｒ_９―Ｚａ―Ａｒ_９―を表し、Ａｒ_９は置換もしくは無置換の芳香環基、ＺａはＯ、Ｓまたはアルキレン基、ＲおよびＲ’は直鎖又は分岐鎖のアルキレン基を表す。ｍは０または１を表す。ｋ、ｊ、ｎ及びＸは前式と同じ。）」、
（８）「電子写真感光体に、少なくとも帯電、画像露光、現像、転写が繰り返し行われる電子写真方法において、前記電子写真感光体が前記第（１）項乃至第（７）項のいずれかに記載の電子写真感光体であることを特徴とする電子写真形成方法」、
（９）「前記画像露光における感光体上の静電潜像書き込みがデジタル方式により行われることを特徴とする前記第（８）項に記載の電子写真形成方法」、
（１０）「少なくとも帯電手段、画像露光手段、現像手段、転写手段および電子写真感光体を具備してなる電子写真装置において、前記電子写真感光体が前記第（１）項乃至第（７）項のいずれかに記載の電子写真感光体により構成されていることを特徴とする電子写真装置」、
（１１）「前記画像露光手段による感光体上の静電潜像書き込みがデジタル方式であることを特徴とする前記第（１０）項に記載の電子写真装置」、
（１２）「電子写真感光体と、帯電手段、画像露光手段、現像手段、転写手段、クリーニング手段および除電手段よりなる群から選ばれた少なくとも一つの手段を含んで一体に支持され、電子写真装置本体に着脱可能とされた電子写真装置用プロセスカートリッジにおいて、前記電子写真感光体が前記第（１）項乃至第（７）項のいずれかに記載の電子写真感光体であることを特徴とする電子写真装置用プロセスカートリッジ」。

(In the formula, Ar ₄ , Ar ₅ , Ar ₆ , Ar ₇ and Ar ₈ represent a substituted or unsubstituted aromatic ring group, Z represents an aromatic ring group or —Ar ₉ —Za—Ar ₉ —, and Ar ₉ represents a substituted group. Or an unsubstituted aromatic ring group, Za represents O, S or an alkylene group, R and R ′ represent a linear or branched alkylene group, m represents 0 or 1, k, j, n and X represent Same as formula.) ",
(8) In the electrophotographic method in which at least charging, image exposure, development, and transfer are repeatedly performed on the electrophotographic photosensitive member, the electrophotographic photosensitive member is any one of the items (1) to (7). The electrophotographic photosensitive member according to the description, "
(9) “The electrophotographic forming method according to item (8), wherein the electrostatic latent image is written on the photosensitive member in the image exposure by a digital method”,
(10) In the electrophotographic apparatus comprising at least a charging unit, an image exposing unit, a developing unit, a transferring unit, and an electrophotographic photosensitive member, the electrophotographic photosensitive member is the item (1) to (7). An electrophotographic apparatus comprising the electrophotographic photosensitive member according to any one of "
(11) “Electrophotographic apparatus according to item (10), wherein the electrostatic latent image writing on the photosensitive member by the image exposure unit is a digital method”,
(12) "The electrophotographic photosensitive member and the electrophotographic apparatus are integrally supported and include at least one means selected from the group consisting of a charging means, an image exposing means, a developing means, a transferring means, a cleaning means, and a static eliminating means. In the process cartridge for an electrophotographic apparatus which is detachably attached to the main body, the electrophotographic photoreceptor is the electrophotographic photoreceptor according to any one of the items (1) to (7). Process cartridge for electrophotographic apparatus ".

  As will be understood from the following detailed and specific description, according to the present invention, the novel methylol compound represented by the general formula (1) is contained, and high sensitivity and high resolution image quality can be obtained over a long period of time. Thus, according to the present invention, both high sensitivity and high stability are realized, and an electrophotographic photosensitive member capable of stably obtaining a high-quality image over a long period of time is provided. An extremely excellent effect is provided that the electrophotographic method, the electrophotographic apparatus, and the process cartridge for the electrophotographic apparatus used are provided.

It is a schematic sectional drawing which shows an example of the layer structure of the electrophotographic photoreceptor of this invention. It is a schematic sectional drawing which shows another example (1) of the layer structure of the electrophotographic photoreceptor of this invention. It is a schematic sectional drawing which shows another example (2) of the layer structure of the electrophotographic photoreceptor of this invention. It is a schematic sectional drawing which shows another example (3) of the layer structure of the electrophotographic photoreceptor of this invention. It is a schematic sectional drawing which shows another example (4) of the layer structure of the electrophotographic photoreceptor of this invention. It is the schematic for demonstrating the electrophotographic process and electrophotographic apparatus of this invention. It is the schematic which shows another example of the electrophotographic process and electrophotographic apparatus of this invention. It is the schematic for demonstrating the process cartridge of this invention. It is an infrared absorption spectrum figure (KBr tablet method) of the compound obtained by the synthesis example 1, a horizontal axis shows a wave number (cm ^<-1 >), and a vertical axis | shaft shows the transmittance | permeability (%). It is an infrared absorption spectrum figure (KBr tablet method) of the compound obtained in the synthesis example 2. It is an infrared absorption spectrum figure (KBr tablet method) of the compound obtained in the synthesis example 3. It is an infrared absorption spectrum figure (KBr tablet method) of the compound obtained in the synthesis example 4. FIG. 6 is an infrared absorption spectrum diagram (KBr tablet method) of the compound obtained in Synthesis Example 5. It is an infrared absorption spectrum figure (KBr tablet method) of the compound obtained in the synthesis example 6. It is an infrared absorption spectrum figure (KBr tablet method) of the compound obtained in the synthesis example 7. It is an infrared absorption spectrum figure (KBr tablet method) of the compound obtained in the synthesis example 8. It is an infrared absorption spectrum figure (KBr tablet method) of the compound obtained in the synthesis example 9. It is an infrared absorption spectrum figure (KBr tablet method) of the compound obtained in the synthesis example 10. It is an infrared absorption spectrum figure (KBr tablet method) of the compound obtained in the synthesis example 11. It is an infrared absorption spectrum figure (KBr tablet method) of the compound obtained in the synthesis example 12.

Hereinafter, the electrophotographic photosensitive member of the present invention, the electrophotographic method using the same, the electrophotographic apparatus, and the electrophotographic process cartridge will be described in detail.
First, details of the novel methylol compound represented by the following general formula (1) to be contained in the photosensitive layer in the present invention will be described.

（式中、Ｘは−Ｏ−、−ＣＨ_２−、−ＣＨ＝ＣＨ−、−ＣＨ_２ＣＨ_２−を表す）

(Wherein, X represents —O—, —CH ₂ —, —CH═CH—, —CH ₂ CH ₂ —)

  This novel methylol compound can easily synthesize the desired methylol compound from the corresponding aldehyde compound represented by the following general formula (6) by a reduction reaction using a reducing agent such as sodium borohydride.

（式中、Ｘは−Ｏ−、−ＣＨ_２−、−ＣＨ＝ＣＨ−、−ＣＨ_２ＣＨ_２−を表す。）

(In the formula, X represents —O—, —CH ₂ —, —CH═CH—, —CH ₂ CH ₂ —).

As described above, the methylol compound represented by the general formula (1) of the present invention is a novel compound, and the corresponding aldehyde compound represented by the general formula (6) is used using a reducing agent such as sodium borohydride. It can be produced by a reduction reaction.
That is, as the specific reduction method described above, a method using sodium borohydride is effective, but the synthesis method for obtaining the methylol compound of the present invention is not limited thereto. Specific synthesis examples will be described in the examples described later.

  Preferred examples of the methylol compound represented by the general formula (1) are given below. However, the present invention is not limited to these compounds.

Next, the layer structure of the electrophotographic photoreceptor of the present invention will be described.
FIG. 1 is a schematic cross-sectional view showing an example of the layer structure of the electrophotographic photosensitive member in the present invention. In FIG. 1, a photosensitive layer (33) mainly composed of a charge generation material and a charge transport material is provided on a conductive support (31). At least the methylol compound of the present invention is contained as a charge transport material for the photosensitive layer (33).
FIG. 2 is a schematic sectional view showing another example (1) of the layer structure of the electrophotographic photosensitive member in the present invention.
In FIG. 2, a charge generation layer (35) mainly composed of a charge generation material and a charge transport layer (37) mainly composed of a charge transport material were laminated on a conductive support (31). It has a configuration. The charge transport layer (37) contains at least the methylol compound of the present invention as a charge transport material.
FIG. 3 is a schematic sectional view showing another example (2) of the layer structure of the electrophotographic photosensitive member in the present invention.
In FIG. 3, a photosensitive layer (33) mainly composed of a charge generation material and a charge transport material is provided on a conductive support (31), and a protective layer (39) is provided on the surface of the photosensitive layer. . At least the methylol compound of the present invention is contained as a charge transport material for the photosensitive layer (33). In this case, the methylol compound of the present invention may be contained in the protective layer (39).
FIG. 4 is a schematic sectional view showing another example (3) of the layer structure of the electrophotographic photosensitive member in the present invention.
In FIG. 4, a structure in which a charge generation layer (35) mainly composed of a charge generation material and a charge transport layer (37) mainly composed of a charge transport material are laminated on a conductive support (31). Further, a protective layer (39) is provided on the charge transport layer. The charge transport layer (37) contains at least the methylol compound of the present invention as a charge transport material. In this case, the methylol compound of the present invention may be contained in the protective layer (39).
FIG. 5 is a schematic cross-sectional view showing another example (4) of the layer structure of the electrophotographic photosensitive member in the present invention.
In FIG. 5, a structure in which a charge transport layer (37) mainly composed of a charge transport material and a charge generation layer (35) mainly composed of a charge generation material are laminated on a conductive support (31). Further, a protective layer (39) is provided on the charge generation layer. The charge transport layer (37) contains at least the methylol compound of the present invention as a charge transport material. In this case, the methylol compound of the present invention may be contained in the protective layer (39).

Examples of the conductive support (31) constituting the electrophotographic photosensitive member include those having a volume resistance of 10 ¹⁰ Ω · cm or less, such as aluminum, nickel, chromium, nichrome, copper, gold, silver, and platinum. Metal or metal oxide such as tin oxide or indium oxide coated with film or cylindrical plastic or paper by vapor deposition or sputtering, or a plate of aluminum, aluminum alloy, nickel, stainless steel, etc. After forming a tube by a method such as extrusion or drawing, a tube subjected to surface treatment such as cutting, superfinishing or polishing can be used. Further, an endless nickel belt and an endless stainless steel belt disclosed in JP-A-52-36016 can also be used as the conductive support (31).

In addition to the above, those obtained by dispersing and coating conductive powder in an appropriate binder resin on the support can also be used as the conductive support (31) of the present invention. That is, the conductive layer can be provided by dispersing the conductive powder and the binder resin in a suitable solvent, for example, tetrahydrofuran, dichloromethane, methyl ethyl ketone, toluene or the like and applying the dispersion onto the support.
Examples of the conductive powder include carbon black, acetylene black, metal powder such as aluminum, nickel, iron, nichrome, copper, zinc, and silver, or metal oxide powder such as conductive tin oxide and ITO. .
The binder resin used simultaneously is polystyrene, styrene-acrylonitrile copolymer, styrene-butadiene copolymer, styrene-maleic anhydride copolymer, polyester, polyvinyl chloride, vinyl chloride-vinyl acetate copolymer. , Polyvinyl acetate, polyvinylidene chloride, polyarylate resin, phenoxy resin, polycarbonate, cellulose acetate resin, ethyl cellulose resin, polyvinyl butyral, polyvinyl formal, polyvinyl toluene, poly-N-vinylcarbazole, acrylic resin, silicone resin, epoxy resin, Examples thereof include thermoplastic, thermosetting resins, and photocurable resins such as melamine resin, urethane resin, phenol resin, and alkyd resin.

  Furthermore, it is electrically conductive by a heat-shrinkable tube in which the conductive powder is contained in a material such as polyvinyl chloride, polypropylene, polyester, polystyrene, polyvinylidene chloride, polyethylene, chlorinated rubber, Teflon (registered trademark) on a suitable cylindrical substrate. Those provided with a conductive layer can also be used favorably as the conductive support (31) of the present invention.

Next, the photosensitive layer constituting the electrophotographic photoreceptor of the present invention will be described.
The photosensitive layer may be a single layer or a laminated layer. For convenience of explanation, the photosensitive layer is first described from the case where it is composed of a charge generation layer (35) and a charge transport layer (37) (FIGS. 2, 4, and 5).
The charge generation layer (35) is a layer mainly composed of a charge generation material, and a known charge generation material can be used. For example, representative examples thereof include CI Pigment Blue 25 (Color Index CI 21180), CI Pigment Red 41 (CI 21200), CI Acid Red 52 (CI 45100), CI Basic Red 3 (CI 45210), and an azo pigment having a carbazole skeleton (CI 45210). For example, described in JP-A-53-95033), azo pigments having a distyrylbenzene skeleton (for example, described in JP-A-53-133445), azo pigments having a triphenylamine skeleton (for example, JP No. 53-132347), an azo pigment having a dibenzothiophene skeleton (for example, described in JP-A No. 54-21728), and an azo pigment having an oxadiazole skeleton (for example, JP-A No. 54-12742). Fluoreno) An azo pigment having a skeleton (for example, described in JP-A No. 54-22834), an azo pigment having a bis-stilbene skeleton (for example, described in JP-A No. 54-17733), a distyryloxadiazole skeleton Azo pigments having a distyrylcarbazole skeleton (for example, described in Japanese Patent Laid-Open No. 54-14967), azo pigments having a benzanthrone skeleton, etc. An azo pigment etc. are mentioned. Further, for example, CI Pigment Blue 16 (CI 74100), Y-type oxotitanium phthalocyanine (for example, described in JP-A No. 64-17066), A (β) -type oxotitanium phthalocyanine, B (α) -type oxotitanium phthalocyanine Type I oxotitanium phthalocyanine (for example, described in JP-A-11-21466), type II chlorogallium phthalocyanine (for example, described in Iijima et al., The 67th Annual Meeting of the Chemical Society of Japan, 1B4, 04 (1994)), V-type hydroxygallium phthalocyanine (for example, described in Daimon et al., The 67th Annual Meeting of the Chemical Society of Japan, 1B4, 05 (1994)), X-type metal-free phthalocyanine (for example, US Pat. No. 3,816,118) Phthalocyanine pigments such as C.I. CI 73410), indigo-based pigments such as CI bat die (CI 73030), manufactured by Argo Scarlet B (Bayer AG), such as perylene pigment, such as in-closet Ren Scarlet R (manufactured by Bayer Co., Ltd.) and the like. In addition, these materials may be used alone or in combination of two or more.

The charge generation layer (35) is obtained by dispersing the charge generation material in a suitable solvent together with a binder resin, if necessary, using a ball mill, an attritor, a sand mill, an ultrasonic wave, etc., on the conductive support. It can be formed by coating and drying.
As the binder resin used for the charge generation layer (35) as necessary, polyamide, polyurethane, epoxy resin, polyketone, polycarbonate, silicone resin, acrylic resin, polyvinyl butyral, polyvinyl formal, polyvinyl ketone, polystyrene, polysulfone, poly -N-vinylcarbazole, polyacrylamide, polyvinyl benzal, polyester, phenoxy resin, vinyl chloride-vinyl acetate copolymer, polyvinyl acetate, polyphenylene oxide, polyamide, polyvinyl pyridine, cellulosic resin, casein, polyvinyl alcohol, polyvinyl pyrrolidone Etc.
The amount of the binder resin is suitably 0 to 500 parts by weight, preferably 10 to 300 parts by weight with respect to 100 parts by weight of the charge generating material. The binder resin may be added before or after dispersion.
Examples of the solvent used above include isopropanol, acetone, methyl ethyl ketone, cyclohexanone, tetrahydrofuran, dioxane, ethyl cellosolve, ethyl acetate, methyl acetate, dichloromethane, dichloroethane, monochlorobenzene, cyclohexane, toluene, xylene, ligroin, and the like. In particular, ketone solvents, ester solvents, and ether solvents are preferably used. These may be used alone or in combination of two or more.

As described above, the charge generation layer (35) is mainly composed of a charge generation material, a solvent, and a binder resin, and includes a sensitizer, a dispersant, a surfactant, silicone oil, and the like. Additives may be included.
Moreover, as a coating method of a coating liquid, methods such as dip coating, spray coating, beat coating, nozzle coating, spinner coating, and ring coating can be used. The thickness of the charge generation layer 35 is suitably about 0.01 to 5 μm, preferably 0.1 to 2 μm.

  Next, the charge transport layer (37) constituting the photosensitive layer is a layer formed mainly of a charge transport material containing a methylol compound represented by the general formula (1) as described above. The charge transport layer (37) can further contain a charge transport material other than the methylol compound represented by the general formula (1). The methylol compound used in the present invention is free from problems such as a decrease in sensitivity and an increase in residual potential even when other charge transport materials are mixed and used, and conversely an improvement in performance.

Examples of the charge transport material other than the methylol compound include a hole transport material, an electron transport material, and a polymer charge transport material. Hereinafter, the hole transport material, the electron transport material, and the polymer charge transport material will be described.
Examples of hole transport materials include poly-N-carbazole and derivatives thereof, poly-γ-carbazolylethyl glutamate and derivatives thereof, pyrene-formaldehyde condensates and derivatives thereof, polyvinylpyrene, polyvinylphenanthrene, oxazole derivatives, imidazole There are derivatives, triphenylamine derivatives, compounds represented by the following general formula (2), and compounds represented by the general formulas (7) to (23).

（式中、Ｒ^２１はメチル基、エチル基、２−ヒドロキシエチル基または２−クロルエチル基を表し、Ｒ^２２はメチル基、エチル基、ベンジル基またはフェニル基を表し、Ｒ^２３は水素原子、塩素原子、臭素原子、炭素数１〜４のアルキル基、炭素数１〜４のアルコキシ基、ジアルキルアミノ基またはニトロ基を表す。）

(Wherein R ²¹ represents a methyl group, an ethyl group, a 2-hydroxyethyl group or a 2-chloroethyl group, R ²² represents a methyl group, an ethyl group, a benzyl group or a phenyl group, and R ²³ represents a hydrogen atom, chlorine An atom, a bromine atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, a dialkylamino group, or a nitro group is represented.)

（式中、Ａｒ^１１はナフタレン環、アントラセン環、ピレン環及びそれらの置換体あるいはピリジン環、フラン環、チオフェン環を表し、Ｒ^２３はアルキル基、フェニル基またはベンジル基を表す。）

(In the formula, Ar ¹¹ represents a naphthalene ring, an anthracene ring, a pyrene ring and a substituted product thereof, or a pyridine ring, a furan ring, or a thiophene ring, and R ²³ represents an alkyl group, a phenyl group, or a benzyl group.)

（式中、Ｒ^２４はアルキル基、ベンジル基、フェニル基またはナフチル基を表し、Ｒ^２５は水素原子、炭素数１〜３のアルキル基、炭素数１〜３のアルコキシ基、ジアルキルアミノ基、ジアラルキルアミノ基またはジアリールアミノ基を表し、ｎは１〜４の整数を表し、ｎが２以上のときはＲ^２５は同じでも異なっていても良い。Ｒ^２６は水素原子またはメトキシ基を表す。）

(Wherein R ²⁴ represents an alkyl group, a benzyl group, a phenyl group or a naphthyl group, and R ²⁵ represents a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, an alkoxy group having 1 to 3 carbon atoms, a dialkylamino group, a dialkyl group) An aralkylamino group or a diarylamino group, n represents an integer of 1 to 4, and when n is 2 or more, R ²⁵ may be the same or different, and R ²⁶ represents a hydrogen atom or a methoxy group.

（式中、Ｒ^３１は炭素数１〜１１のアルキル基、置換もしくは無置換のフェニル基または複素環基を表し、Ｒ^３２、Ｒ^３３はそれぞれ同一でも異なっていてもよく、水素原子、炭素数１〜４のアルキル基、ヒドロキシアルキル基、クロルアルキル基または置換もしくは無置換のアラルキル基を表し、また、Ｒ^３２とＲ^３３は互いに結合し窒素を含む複素環を形成していても良い。Ｒ^３４は同一でも異なっていてもよく、水素原子、炭素数１〜４のアルキル基、アルコキシ基またはハロゲン原子を表す。）

(In the formula, R ³¹ represents an alkyl group having 1 to 11 carbon atoms, a substituted or unsubstituted phenyl group or a heterocyclic group, and R ³² and R ³³ may be the same or different, and each represents a hydrogen atom or a carbon number. It represents an alkyl group of 1 to 4, a hydroxyalkyl group, a chloroalkyl group or a substituted or unsubstituted aralkyl group, and R ³² and R ³³ may be bonded to each other to form a nitrogen-containing heterocyclic ring. ³⁴ may be the same or different and each represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group or a halogen atom.

（式中、Ｒ^３６は水素原子またはハロゲン原子を表し、Ａｒ^１２は置換もしくは無置換のフェニル基、ナフチル基、アントリル基またはカルバゾリル基を表す。）

(In the formula, R ³⁶ represents a hydrogen atom or a halogen atom, and Ar ¹² represents a substituted or unsubstituted phenyl group, naphthyl group, anthryl group, or carbazolyl group.)

（式中、Ｒ^３７は水素原子、ハロゲン原子、シアノ基、炭素数１〜４のアルコキシ基または炭素数１〜４のアルキル基を表し、Ａｒ^１３は

(In the formula, R ³⁷ represents a hydrogen atom, a halogen atom, a cyano group, an alkoxy group having 1 to 4 carbon atoms or an alkyl group having 1 to 4 carbon atoms; Ar ¹³ represents

を表し、Ｒ^１３２は炭素数１〜４のアルキル基を表し、Ｒ^１３３は水素原子、ハロゲン原子、炭素数１〜４のアルキル基、炭素数１〜４のアルコキシ基またはジアルキルアミノ基を表し、ｎは１または２であって、ｎが２のときはＲ^１３３は同一でも異なっていてもよく、Ｒ^１３４、Ｒ^１３５は水素原子、炭素数１〜４の置換もしくは無置換のアルキル基または置換もしくは無置換のベンジル基を表す。）

R ¹³² represents an alkyl group having 1 to 4 carbon atoms, R ¹³³ represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, or a dialkylamino group, n is 1 or 2, and when n is 2, R ¹³³ may be the same or different, and R ¹³⁴ and R ¹³⁵ are hydrogen atoms, substituted or unsubstituted alkyl groups having 1 to 4 carbon atoms or substituted Alternatively, it represents an unsubstituted benzyl group. )

（式中、Ｒ^３８はカルバゾリル基、ピリジル基、チエニル基、インドリル基、フリル基あるいはそれぞれ置換もしくは非置換のフェニル基、スチリル基、ナフチル基、またはアントリル基であって、これらの置換基がジアルキルアミノ基、アルキル基、アルコキシ基、カルボキシ基またはそのエステル、ハロゲン原子、シアノ基、アラルキルアミノ基、Ｎ−アルキル−Ｎ−アラルキルアミノ基、アミノ基、ニトロ基及びアセチルアミノ基からなる群から選ばれた基を表す。）

(Wherein R ³⁸ is a carbazolyl group, pyridyl group, thienyl group, indolyl group, furyl group or a substituted or unsubstituted phenyl group, styryl group, naphthyl group, or anthryl group, and these substituents are dialkyl. Selected from the group consisting of amino group, alkyl group, alkoxy group, carboxy group or ester thereof, halogen atom, cyano group, aralkylamino group, N-alkyl-N-aralkylamino group, amino group, nitro group and acetylamino group Represents a group.

（式中、Ｒ^３９は低級アルキル基、置換もしくは無置換のフェニル基、またはベンジル基を表し、Ｒ^４０、Ｒ^４１は水素原子、低級アルキル基、低級アルコキシ基、ハロゲン原子、ニトロ基、アミノ基あるいは低級アルキル基またはベンジル基で置換されたアミノ基を表し、ｎは１または２の整数を表す。）

(In the formula, R ³⁹ represents a lower alkyl group, a substituted or unsubstituted phenyl group, or a benzyl group, and R ⁴⁰ and R ⁴¹ represent a hydrogen atom, a lower alkyl group, a lower alkoxy group, a halogen atom, a nitro group, and an amino group. Alternatively, it represents an amino group substituted with a lower alkyl group or a benzyl group, and n represents an integer of 1 or 2.)

（式中、Ｒ^１４は水素原子、アルキル基、アルコキシ基またはハロゲン原子を表し、Ｒ^４３およびＲ^４４は置換もしくは無置換のアリール基を表し、Ｒ^４５は水素原子、低級アルキル基または置換もしくは無置換のフェニル基を表し、また、Ａｒ^１４は置換もしくは無置換のフェニル基またはナフチル基を表す。）

(Wherein R ¹⁴ represents a hydrogen atom, an alkyl group, an alkoxy group or a halogen atom, R ⁴³ and R ⁴⁴ represent a substituted or unsubstituted aryl group, and R ⁴⁵ represents a hydrogen atom, a lower alkyl group or a substituted or unsubstituted group. Represents a substituted phenyl group, and Ar ¹⁴ represents a substituted or unsubstituted phenyl group or a naphthyl group.)

（式中、ｎは０または１の整数、Ｒ^１は水素原子、アルキル基または置換もしくは無置換のフェニル基を表し、Ａｒ^１は置換もしくは未置換のアリール基を表し、Ｒ^５は置換アルキル基を含むアルキル基、あるいは置換もしくは無置換のアリール基を表し、Ａは

Wherein n represents an integer of 0 or 1, R ¹ represents a hydrogen atom, an alkyl group or a substituted or unsubstituted phenyl group, Ar ¹ represents a substituted or unsubstituted aryl group, and R ⁵ represents a substituted alkyl group. Represents an alkyl group containing or a substituted or unsubstituted aryl group, and A is

９−アントリル基または置換もしくは無置換のカルバゾリル基を表し、ここでＲ^２は水素原子、アルキル基、アルコキシ基、ハロゲン原子または

Represents a 9-anthryl group or a substituted or unsubstituted carbazolyl group, wherein R ² represents a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom or

（ただし、Ｒ^３およびＲ^４は置換もしくは無置換のアリール基を示し、Ｒ^３およびＲ^４は同じでも異なっていてもよく、Ｒ^４は環を形成しても良い）を表し、ｍが２以上の時Ｒ^２は同一でも異なっても良い。また、ｎが０の時、ＡとＲ^１は共同で環を形成しても良い。）

Wherein R ³ and R ⁴ represent a substituted or unsubstituted aryl group, R ³ and R ⁴ may be the same or different, and R ⁴ may form a ring, and m is 2 At this time, R ² may be the same or different. When n is 0, A and R ¹ may form a ring together. )

（式中、Ｒ^４６、Ｒ^４７およびＲ^４８は水素原子、低級アルキル基、低級アルコキシ基、ハロゲン原子またはジアルキルアミノ基を表し、ｎは０または１を表す。）

(Wherein R ⁴⁶ , R ⁴⁷ and R ⁴⁸ represent a hydrogen atom, a lower alkyl group, a lower alkoxy group, a halogen atom or a dialkylamino group, and n represents 0 or 1).

（式中、Ｒ^４９およびＲ^５０は置換アルキル基を含むアルキル基、または置換もしくは未置換のアリール基を表し、Ａ^１は置換アミノ基、置換もしくは未置換のアリール基またはアリル基を表す。）

(Wherein R ⁴⁹ and R ⁵⁰ represent an alkyl group containing a substituted alkyl group or a substituted or unsubstituted aryl group, and A ¹ represents a substituted amino group, a substituted or unsubstituted aryl group or an allyl group.)

（式中、Ｘ^１は水素原子、低級アルキル基またはハロゲン原子を表し、Ｒ^５１は置換アルキル基を含むアルキル基、または置換もしくは無置換のアリール基を表し、Ａ^２は置換アミノ基または置換もしくは無置換のアリール基を表す。）

Wherein X ¹ represents a hydrogen atom, a lower alkyl group or a halogen atom, R ⁵¹ represents an alkyl group containing a substituted alkyl group, or a substituted or unsubstituted aryl group, and A ² represents a substituted amino group or a substituted or unsubstituted aryl group Represents an unsubstituted aryl group.)

（式中、Ｒ^５２は低級アルキル基、低級アルコキシ基またはハロゲン原子を表し、Ｒ^５３、Ｒ^５４は同じでも異なっていてもよく、水素原子、低級アルキル基、低級アルコキシ基またはハロゲン原子を表し、ｌ、ｍ、ｎは０〜４の整数を表す。）

(In the formula, R ⁵² represents a lower alkyl group, a lower alkoxy group or a halogen atom, R ⁵³ and R ⁵⁴ may be the same or different, and each represents a hydrogen atom, a lower alkyl group, a lower alkoxy group or a halogen atom; l, m, and n represent an integer of 0 to 4.)

（式中、Ｒ^５５、Ｒ^５７およびＲ^５８は水素原子、アミノ基、アルコキシ基、チオアルコキシ基、アリールオキシ基、メチレンジオキシ基、置換もしくは無置換のアルキル基、ハロゲン原子または置換もしくは無置換のアリール基を、Ｒ^５６は水素原子、アルコキシ基、置換もしくは無置換のアルキル基またはハロゲン原子を表す。ただし、Ｒ^５５、Ｒ^５６、Ｒ^５７およびＲ^５８はすべて水素原子である場合は除く。また、ｋ，ｌ，ｍおよびｎは１、２、３または４の整数であり、それぞれが２、３または４の整数の時は、前記Ｒ^５５、Ｒ^５６、Ｒ^５７およびＲ^５８は同じでも異なっていても良い。）

(Wherein R ⁵⁵ , R ⁵⁷ and R ⁵⁸ are a hydrogen atom, an amino group, an alkoxy group, a thioalkoxy group, an aryloxy group, a methylenedioxy group, a substituted or unsubstituted alkyl group, a halogen atom, or a substituted or unsubstituted group. R ⁵⁶ represents a hydrogen atom, an alkoxy group, a substituted or unsubstituted alkyl group or a halogen atom, except that R ⁵⁵ , R ⁵⁶ , R ⁵⁷ and R ⁵⁸ are all hydrogen atoms. K, l, m and n are integers of 1, 2, 3 or 4, and when each of them is an integer of 2, 3 or 4, R ⁵⁵ , R ⁵⁶ , R ⁵⁷ and R ⁵⁸ are the same. May be different.)

（式中、Ａｒ^１６は置換基を有してもよい炭素数１８個以下の縮合多環式炭化水素基を表し、また、Ｒ^５９およびＲ^６０は水素原子、ハロゲン原子、置換もしくは無置換のアルキル基、アルコキシ基、置換もしくは無置換のフェニル基を表し、それぞれ同じでも異なっていても良い。ｎは１もしくは２の整数を表す。）

(In the formula, Ar ¹⁶ represents an optionally substituted condensed polycyclic hydrocarbon group having 18 or less carbon atoms, and R ⁵⁹ and R ⁶⁰ are each a hydrogen atom, a halogen atom, a substituted or unsubstituted group. An alkyl group, an alkoxy group, a substituted or unsubstituted phenyl group, which may be the same or different, and n represents an integer of 1 or 2.)

（式中、Ａｒ^１７は置換もしくは無置換の芳香族炭化水素基を表し、Ａ^３は

(In the formula, Ar ¹⁷ represents a substituted or unsubstituted aromatic hydrocarbon group, and A ³ represents

（ただし、Ａｒ^１８は置換もしくは無置換の芳香族炭化水素基を表し、Ｒ^６１およびＲ^６２は置換もしくは無置換のアルキル基、または置換もしくは無置換のアリール基である。）を表す。）

(Wherein Ar ¹⁸ represents a substituted or unsubstituted aromatic hydrocarbon group, and R ⁶¹ and R ⁶² represent a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group). )

（式中、Ａｒ^１９は置換もしくは無置換の芳香族炭化水素基を、Ｒ^６３は水素原子、置換もしくは無置換のアルキル基、または置換もしくは無置換のアリール基を表す。ｎは０または１、ｍは１または２であって、ｎ＝０、ｍ＝１の場合、Ａｒ^１９とＲ^６３は共同で環を形成しても良い。）

(In the formula, Ar ¹⁹ represents a substituted or unsubstituted aromatic hydrocarbon group, R ⁶³ represents a hydrogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group. N represents 0 or 1, m is 1 or 2, and when n = 0 and m = 1, Ar ¹⁹ and R ⁶³ may jointly form a ring.)

Examples of the compound represented by the general formula (7) include 9-ethylcarbazole-3-carbaldehyde 1-methyl-1-phenylhydrazone, 9-ethylcarbazole-3-carbaldehyde 1-benzyl-1-phenylhydrazone. 9-ethylcarbazole-3-carbaldehyde 1,1-diphenylhydrazone and the like.
Examples of the compound represented by the general formula (8) include 4-diethylaminostyryl-β-carbaldehyde 1-methyl-1-phenylhydrazone, 4-methoxynaphthalene-1-carbaldehyde 1-benzyl-1- There is phenyl hydrazone.
Examples of the compound represented by the general formula (9) include 4-methoxybenzaldehyde 1-methyl-1-phenylhydrazone, 2,4-dimethoxybenzaldehyde 1-benzyl-1-phenylhydrazone, 4-diethylaminobenzaldehyde 1,1. -Diphenylhydrazone, 4-methoxybenzaldehyde 1- (4-methoxy) phenylhydrazone, 4-diphenylaminobenzaldehyde 1-benzyl-1-phenylhydrazone, 4-dibenzylaminobenzaldehyde 1,1-diphenylhydrazone and the like.
Examples of the compound represented by the general formula (10) include 1,1-bis (4-dibenzylaminophenyl) propane, tris (4-diethylaminophenyl) methane, and 1,1-bis (4-di). Benzylaminophenyl) propane, 2,2′-dimethyl-4,4′-bis (diethylamino) -triphenylmethane, and the like.
Examples of the compound represented by the general formula (11) include 9- (4-diethylaminostyryl) anthracene and 9-bromo-10- (4-diethylaminostyryl) anthracene.
Examples of the compound represented by the general formula (12) include 9- (4-dimethylaminobenzylidene) fluorene and 3- (9-fluorenylidene) -9-ethylcarbazole.
Examples of the compound represented by the general formula (13) include 1,2-bis (4-diethylaminostyryl) benzene and 1,2-bis (2,4-dimethoxystyryl) benzene.
Examples of the compound represented by the general formula (14) include 3-styryl-9-ethylcarbazole and 3- (4-methoxystyryl) -9-ethylcarbazole.
Examples of the compound represented by the general formula (15) include 4-diphenylaminostilbene, 4-dibenzylaminostilbene, 4-ditolylaminostilbene, 1- (4-diphenylaminostyryl) naphthalene, 1- (4 -Diphenylaminostyryl) naphthalene.
Examples of the compound represented by the general formula (2) include 4′-diphenylamino-α-phenylstilbene and 4′-bis (4-methylphenyl) amino-α-phenylstilbene.
Examples of the compound represented by the general formula (16) include 1-phenyl-3- (4-diethylaminostyryl) -5- (4-diethylaminophenyl) pyrazoline.
Examples of the compound represented by the general formula (17) include 2,5-bis (4-diethylaminophenyl) -1,3,4-oxadiazole, 2-N, N-diphenylamino-5- (4 -Diethylaminophenyl) -1,3,4-oxadiazole, 2- (4-dimethylaminophenyl) -5- (4-diethylaminophenyl) -1,3,4-oxadiazole and the like.
Examples of the compound represented by the general formula (18) include 2-N, N-diphenylamino-5- (N-ethylcarbazol-3-yl) -1,3,4-oxadiazole, 2- ( 4-diethylaminophenyl) -5- (N-ethylcarbazol-3-yl) -1,3,4-oxadiazole.
Examples of the benzidine compound represented by the general formula (19) include N, N′-diphenyl-N, N′-bis (3-methylphenyl)-[1,1′-biphenyl] -4,4′-. Examples include diamine, 3,3′-dimethyl-N, N, N ′, N′-tetrakis (4-methylphenyl)-[1,1′-biphenyl] -4,4′-diamine.
Examples of the biphenylylamine compound represented by the general formula (20) include 4′-methoxy-N, N-diphenyl- [1,1′-biphenyl] -4-amine and 4′-methyl-N. , N-bis (4-methylphenyl)-[1,1′-biphenyl] -4-amine, 4′-methoxy-N, N-bis (4-methylphenyl)-[1,1′-biphenyl]- 4-amine, N, N-bis (3,4-dimethylphenyl)-[1,1′-biphenyl] -4-amine and the like. Examples of the triarylamine compound represented by the general formula (21) include N, N-diphenyl-pyrene-1-amine, N, N-di-p-tolyl-pyren-1-amine, N, N-di-p-tolyl-1-naphthylamine, N, N-di (p-tolyl) -1-phenanthrylamine, 9,9-dimethyl-2- (di-p-tolylamino) fluorene, N, N , N ′, N′-tetrakis (4-methylphenyl) -phenanthrene-9,10-diamine, N, N, N ′, N′-tetrakis (3-methylphenyl) -m-phenylenediamine, and the like.
Examples of the diolefin aromatic compound represented by the general formula (22) include 1,4-bis (4-diphenylaminostyryl) benzene and 1,4-bis [4-di (p-tolyl) amino. Styryl] benzene. Examples of the styrylpyrene compound represented by the general formula (23) include 1- (4-diphenylaminostyryl) pyrene and 1- (N, N-di-p-tolyl-4-aminostyryl) pyrene. is there.

Examples of the electron transport material include chloroanil, bromoanil, tetracyanoethylene, tetracyanoquinodimethane, 2,4,7-trinitro-9-fluorenone, 2,4,5,7-tetranitro-9-fluorenone, 2,4,5,7-tetranitroxanthone, 2,4,8-trinitrothioxanthone, 2,6,8-trinitro-indeno4H-indeno [1,2-b] thiophen-4-one, 1,3 , 7-trinitrodibenzothiophene-5,5-dioxide and the like, and the electron transport materials listed in the following general formulas (24), (25), (26) and (27) are preferably used. be able to.
These charge transport materials may be used alone or in combination of two or more.

（式中Ｒ^６４、Ｒ^６５およびＲ^６６は水素原子、ハロゲン原子、置換もしくは無置換のアルキル基、アルコキシ基、置換もしくは無置換のフェニル基を表し、それぞれ同じでも異なっていても良い。）

(Wherein R ⁶⁴ , R ⁶⁵ and R ⁶⁶ represent a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group, an alkoxy group, or a substituted or unsubstituted phenyl group, and may be the same or different.)

（式中Ｒ^６７、Ｒ^６８は水素原子、置換もしくは無置換のアルキル基、置換もしくは無置換のフェニル基を表し、それぞれ同じでも異なっていても良い。）

(Wherein R ⁶⁷ and R ⁶⁸ represent a hydrogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted phenyl group, and may be the same or different.)

（式中Ｒ^６９、Ｒ^７０およびＲ^７１は水素原子、ハロゲン原子、置換もしくは無置換のアルキル基、アルコキシ基、置換もしくは無置換のフェニル基を表し、それぞれ同じでも異なっていても良い。）

(Wherein R ⁶⁹ , R ⁷⁰ and R ⁷¹ represent a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group, an alkoxy group, or a substituted or unsubstituted phenyl group, which may be the same or different.)

〔式中、Ｒ^７２は置換基を有してもよいアルキル基、または置換基を有してもよいアリール基を示し、Ｒ^７３は置換基を有してもよいアルキル基、置換基を有してもよいアリール基、または、次の一般式、すなわち−Ｏ−Ｒ^７４、で表される基を示す。Ｒ^７４は、置換基を有してもよいアルキル基、または置換基を有してもよいアリール基を示す。〕

[Wherein R ⁷² represents an alkyl group which may have a substituent or an aryl group which may have a substituent, and R ⁷³ has an alkyl group which may have a substituent or a substituent. Or a group represented by the following general formula, that is, —O—R ⁷⁴ . R ⁷⁴ represents an alkyl group which may have a substituent, or an aryl group which may have a substituent. ]

  As the binder resin, polystyrene, styrene-acrylonitrile copolymer, styrene-butadiene copolymer, styrene-maleic anhydride copolymer, polyester, polyvinyl chloride, vinyl chloride-vinyl acetate copolymer, polyvinyl acetate, Polyvinylidene chloride, polyarylate resin, phenoxy resin, polycarbonate, cellulose acetate resin, ethyl cellulose resin, polyvinyl butyral, polyvinyl formal, polyvinyl toluene, poly-N-vinyl carbazole, acrylic resin, silicone resin, epoxy resin, melamine resin, urethane resin And thermoplastic or thermosetting resins such as phenol resins and alkyd resins.

  When the charge transport material and the methylol compound of the present invention are mixed and contained in the charge transport layer, the total amount is 20 to 300 parts by weight, preferably 40 to 150 parts by weight, based on 100 parts by weight of the binder resin. It is. The thickness of the charge transport layer is preferably 30 μm or less from the viewpoint of resolution and responsiveness. Regarding the lower limit, although it differs depending on the system to be used (particularly the charging potential), 5 μm or more is preferable.

  As the solvent used here, tetrahydrofuran, dioxane, toluene, dichloromethane, monochlorobenzene, dichloroethane, cyclohexanone, methyl ethyl ketone, acetone and the like are used. The charge transport materials may be used alone or in combination of two or more.

As the antioxidant that can be used in the present invention, a general antioxidant described later can be used, and (c) hydroquinone-based compounds and (f) hindered amine-based compounds are particularly effective.
However, the antioxidant used here is used for the purpose of protecting the alteration of the benzidine compound used in the present invention, unlike the purpose described later. Therefore, these antioxidants are preferably contained in the coating liquid in the step before containing the benzidine compound of the present invention, and the addition amount is 0.1 to 200 wt% with respect to the benzidine compound. Can be effective enough.

  For the charge transport layer, a polymer charge transport material having a function as a charge transport material and a function as a binder resin is also preferably used. The charge transport layer composed of these polymer charge transport materials is excellent in wear resistance. As the polymer charge transport material, known materials can be used, and in particular, a polycarbonate containing a triarylamine structure in the main chain and / or side chain is preferably used. Among these, polymer charge transport materials represented by the general formulas (I) to (XI) are preferably used. These are illustrated below and specific examples are shown.

[Polymer charge transport material of general formula (I)]

（式中、Ｒ_１，Ｒ_２，Ｒ_３はそれぞれ独立して置換もしくは無置換のアルキル基又はハロゲン原子、Ｒ_４は水素原子又は置換もしくは無置換のアルキル基、Ｒ_５，Ｒ_６は置換もしくは無置換のアリール基、ｏ，ｐ，ｑはそれぞれ独立して０〜４の整数、ｋ，ｊは組成を表し、０．１≦ｋ≦１、０≦ｊ≦０．９、ｎは繰り返し単位数を表し５〜５０００の整数である。Ｘは脂肪族の２価基、環状脂肪族の２価基、または下記一般式で表される２価基を表す。）

(Wherein R ₁ , R ₂ and R ₃ are each independently a substituted or unsubstituted alkyl group or a halogen atom, R ₄ is a hydrogen atom or a substituted or unsubstituted alkyl group, and R ₅ and R ₆ are substituted or Unsubstituted aryl group, o, p and q are each independently an integer of 0 to 4, k and j represent a composition, 0.1 ≦ k ≦ 1, 0 ≦ j ≦ 0.9, and n is a repeating unit And represents an integer of 5 to 5000. X represents an aliphatic divalent group, a cycloaliphatic divalent group, or a divalent group represented by the following general formula.

（式中、Ｒ_１０１，Ｒ_１０２は各々独立して置換もしくは無置換のアルキル基、アリール基またはハロゲン原子を表す。ｌ、ｍは０〜４の整数、Ｙは単結合、炭素原子数１〜１２の直鎖状、分岐状もしくは環状のアルキレン基、−Ｏ−，−Ｓ−，−ＳＯ−，−ＳＯ_２−，−ＣＯ−，−ＣＯ−Ｏ−Ｚ−Ｏ−ＣＯ−（式中Ｚは脂肪族の２価基を表す。）または、

(In the formula, R ₁₀₁ and R ₁₀₂ each independently represents a substituted or unsubstituted alkyl group, aryl group or halogen atom. L and m are integers of 0 to 4, Y is a single bond, and has 1 to 1 carbon atoms. 12 linear, branched or cyclic alkylene groups, —O—, —S—, —SO—, —SO ₂ —, —CO—, —CO—O—Z—O—CO— (wherein Z Represents an aliphatic divalent group) or

（式中、ａは１〜２０の整数、ｂは１〜２０００の整数、Ｒ_１０３、Ｒ_１０４は置換または無置換のアルキル基又はアリール基を表す。）を表す。ここで、Ｒ_１０１とＲ_１０２，Ｒ_１０３とＲ_１０４は、それぞれ同一でも異なってもよい。

(Wherein, a represents an integer of 1 to 20, b represents an integer of 1 to 2000, R ₁₀₃ and R ₁₀₄ represent a substituted or unsubstituted alkyl group or aryl group). Here, R ₁₀₁ and R ₁₀₂ , R ₁₀₃ and R ₁₀₄ may be the same or different.

[Polymer charge transport material of general formula (II)]

（式中、Ｒ_７，Ｒ_８は置換もしくは無置換のアリール基、Ａｒ_１，Ａｒ_２，Ａｒ_３は同一あるいは異なるアリレン基を表す。Ｘ，ｋ，ｊおよびｎは、一般式（Ｉ）の場合と同じである。）

(In the formula, R ₇ and R ₈ are substituted or unsubstituted aryl groups, Ar ₁ , Ar ₂ , and Ar ₃ are the same or different arylene groups. X, k, j, and n are represented by the formula (I). Same as the case.)

[Polymer charge transport material of general formula (III)]

（式中、Ｒ_９，Ｒ_１０は置換もしくは無置換のアリール基、Ａｒ_４，Ａｒ_５，Ａｒ_６は同一あるいは異なるアリレン基を表す。Ｘ，ｋ，ｊおよびｎは、一般式（Ｉ）の場合と同じである。）

(In the formula, R ₉ and R ₁₀ are substituted or unsubstituted aryl groups, Ar ₄ , Ar ₅ , and Ar ₆ are the same or different arylene groups. X, k, j, and n are represented by the formula (I). Same as the case.)

[Polymer charge transport material of general formula (IV)]

（式中、Ｒ_１１，Ｒ_１２は置換もしくは無置換のアリール基、Ａｒ_７，Ａｒ_８，Ａｒ_９は同一あるいは異なるアリレン基、ｐは１〜５の整数を表す。Ｘ，ｋ，ｊおよびｎは、一般式（Ｉ）の場合と同じである。

Wherein R ₁₁ and R ₁₂ are substituted or unsubstituted aryl groups, Ar ₇ , Ar ₈ and Ar ₉ are the same or different arylene groups, and p is an integer of 1 to 5. X, k, j and n Is the same as in the general formula (I).

[Polymer charge transport material of general formula (V)]

（式中、Ｒ_１３，Ｒ_１４は置換もしくは無置換のアリール基、Ａｒ_１０，Ａｒ_１１，Ａｒ_１２は同一あるいは異なるアリレン基、Ｘ_１，Ｘ_２は置換もしくは無置換のエチレン基、又は置換もしくは無置換のビニレン基を表す。Ｘ，ｋ，ｊおよびｎは、一般式（Ｉ）の場合と同じである。）

(Wherein R ₁₃ and R ₁₄ are substituted or unsubstituted aryl groups, Ar ₁₀ , Ar ₁₁ and Ar ₁₂ are the same or different arylene groups, X ₁ and X ₂ are substituted or unsubstituted ethylene groups, or substituted or unsubstituted Represents an unsubstituted vinylene group, and X, k, j and n are the same as those in formula (I).)

[Polymer charge transport material of general formula (VI)]

（式中、Ｒ_１５，Ｒ_１６，Ｒ_１７，Ｒ_１８は置換もしくは無置換のアリール基、Ａｒ_１３，Ａｒ_１４，Ａｒ_１５，Ａｒ_１６は同一あるいは異なるアリレン基、Ｙ_１，Ｙ_２，Ｙ_３は単結合、置換もしくは無置換のアルキレン基、置換もしくは無置換のシクロアルキレン基、置換もしくは無置換のアルキレンエーテル基、酸素原子、硫黄原子、ビニレン基を表し同一であっても異なってもよい。Ｘ，ｋ，ｊおよびｎは、一般式（Ｉ）の場合と同じである。）

(Wherein R ₁₅ , R ₁₆ , R ₁₇ and R ₁₈ are substituted or unsubstituted aryl groups, Ar ₁₃ , Ar ₁₄ , Ar ₁₅ and Ar ₁₆ are the same or different arylene groups, Y ₁ , Y ₂ and Y _3. Represents a single bond, a substituted or unsubstituted alkylene group, a substituted or unsubstituted cycloalkylene group, a substituted or unsubstituted alkylene ether group, an oxygen atom, a sulfur atom, or a vinylene group, which may be the same or different. X, k, j and n are the same as those in the general formula (I).)

[Polymer charge transport material of general formula (VII)]

（式中、Ｒ_１９，Ｒ_２０は水素原子、置換もしくは無置換のアリール基を表し，Ｒ_１９とＲ_２０は環を形成していてもよい。Ａｒ_１７，Ａｒ_１８，Ａｒ_１９は同一あるいは異なるアリレン基を表す。Ｘ，ｋ，ｊおよびｎは、一般式（Ｉ）の場合と同じである。）

(In the formula, R ₁₉ and R ₂₀ represent a hydrogen atom or a substituted or unsubstituted aryl group, and R ₁₉ and R ₂₀ may form a ring. Ar ₁₇ , Ar ₁₈ and Ar ₁₉ may be the same or different. Represents an arylene group, and X, k, j, and n are the same as those in formula (I).

[Polymer charge transport material of general formula (VIII)]

（式中、Ｒ_２１は置換もしくは無置換のアリール基、Ａｒ_２０，Ａｒ_２１，Ａｒ_２２，Ａｒ_２３は同一あるいは異なるアリレン基を表す。Ｘ，ｋ，ｊおよびｎは、一般式（Ｉ）の場合と同じである。）

(In the formula, R ₂₁ represents a substituted or unsubstituted aryl group, Ar ₂₀ , Ar ₂₁ , Ar ₂₂ , Ar ₂₃ represent the same or different arylene groups. X, k, j, and n are represented by the formula (I). Same as the case.)

[Polymer charge transport material of general formula (IX)]

（式中、Ｒ_２２，Ｒ_２３，Ｒ_２４，Ｒ_２５は置換もしくは無置換のアリール基、Ａｒ_２４，Ａｒ_２５，Ａｒ_２６，Ａｒ_２７，Ａｒ_２８は同一あるいは又は異なるアリレン基を表す。Ｘ，ｋ，ｊおよびｎは、一般式（Ｉ）の場合と同じである。）

(In the formula, R ₂₂ , R ₂₃ , R ₂₄ and R ₂₅ represent a substituted or unsubstituted aryl group, Ar ₂₄ , Ar ₂₅ , Ar ₂₆ , Ar ₂₇ and Ar ₂₈ represent the same or different arylene groups. X, k, j and n are the same as in the case of the general formula (I).)

[Polymer charge transport material of general formula (X)]

（式中、Ｒ_２６，Ｒ_２７は置換もしくは無置換のアリール基、Ａｒ_２９，Ａｒ_３０，Ａｒ_３１は同一あるいは異なるアリレン基を表す。Ｘ，ｋ，ｊおよびｎは、一般式（Ｉ）の場合と同じである。）

(In the formula, R ₂₆ and R ₂₇ represent a substituted or unsubstituted aryl group, Ar ₂₉ , Ar ₃₀ and Ar ₃₁ represent the same or different arylene groups. X, k, j and n represent those of the general formula (I). Same as the case.)

[Polymer charge transport material of general formula (XI)]

（式中、Ａｒ_１、Ａｒ_２、Ａｒ_３、Ａｒ_４およびＡｒ_５は置換もしくは無置換の芳香環基、Ｚは芳香環基または−Ａｒ_６−Ｚａ−Ａｒ_６−を表し、Ａｒ_６は置換もしくは無置換の芳香環基、ＺａはＯ、Ｓまたはアルキレン基、ＲおよびＲ’は直鎖又は分岐鎖のアルキレン基を表す。ｍは０または１を表す。ｋ、ｊ、ｎ及びＸは前式と同じ。）

(In the formula, Ar ₁ , Ar ₂ , Ar ₃ , Ar ₄ and Ar ₅ represent a substituted or unsubstituted aromatic ring group, Z represents an aromatic ring group or —Ar ₆ —Za—Ar ₆ —, and Ar ₆ represents a substituted group. Or an unsubstituted aromatic ring group, Za represents O, S or an alkylene group, R and R ′ represent a linear or branched alkylene group, m represents 0 or 1, k, j, n and X represent Same as formula.)

The charge transport layer (37) can be formed by dissolving or dispersing the charge transport material alone or in a binder resin and an appropriate solvent, and applying and drying the solution on the charge generation layer. Further, if necessary, two or more kinds of plasticizers, leveling agents, antioxidants and the like can be added.
As a coating method of the coating liquid obtained as described above, conventional coating methods such as dip coating, spray coating, beat coating, nozzle coating, spinner coating, ring coating, and the like can be used.

Next, the case where the photosensitive layer has a single layer configuration (33) will be described. A photoreceptor in which the above-described charge generating material is dispersed in a binder resin can be used. The photosensitive layer can be formed by dissolving or dispersing a charge generating substance, a charge transporting substance, and a binder resin in a suitable solvent, and applying and drying them. Moreover, a plasticizer, a leveling agent, antioxidant, etc. can also be added as needed.
As the binder resin, in addition to the binder resin previously mentioned in the charge transport layer (37), the binder resin mentioned in the charge generation layer 35 may be mixed and used. Of course, the polymer charge transport materials mentioned above can also be used favorably. The amount of the charge generating material with respect to 100 parts by weight of the binder resin is preferably 5 to 40 parts by weight, and the amount of the charge transporting material is preferably 0 to 190 parts by weight, and more preferably 50 to 150 parts by weight. The photosensitive layer is formed by dip coating, spray coating, bead coating, a coating solution in which a charge generating material and a binder resin are dispersed together with a charge transporting material using a solvent such as tetrahydrofuran, dioxane, dichloroethane, and cyclohexane. It can be formed by coating with a ring coat or the like. The film thickness of the photosensitive layer is suitably about 5 to 25 μm.

  In the photoreceptor of the present invention, an undercoat layer can be provided between the conductive support (31) and the photosensitive layer. In general, the undercoat layer is mainly composed of a resin. However, considering that the photosensitive layer is coated with a solvent on these resins, the resin may be a resin having high solvent resistance with respect to a general organic solvent. desirable. Examples of such resins include water-soluble resins such as polyvinyl alcohol, casein, and sodium polyacrylate, alcohol-soluble resins such as copolymer nylon and methoxymethylated nylon, polyurethane, melamine resin, phenol resin, alkyd-melamine resin, and epoxy. Examples thereof include a curable resin that forms a three-dimensional network structure such as a resin. Further, a metal oxide fine powder pigment exemplified by titanium oxide, silica, alumina, zirconium oxide, tin oxide, indium oxide and the like may be added to the undercoat layer in order to prevent moire and reduce residual potential.

  These undercoat layers can be formed using an appropriate solvent and a coating method like the above-mentioned photosensitive layer. Furthermore, a silane coupling agent, a titanium coupling agent, a chromium coupling agent, or the like can be used as the undercoat layer of the present invention. In addition, for the undercoat layer of the present invention, a vacuum thin film is formed of Al2O3 provided by anodic oxidation, organic substances such as polyparaxylylene (parylene), and inorganic substances such as SiO2, SnO2, TiO2, ITO, CeO2 Those provided by the law can also be used satisfactorily. In addition, known ones can be used. The thickness of the undercoat layer is suitably from 0 to 5 μm.

  In the photoreceptor of the present invention, a protective layer (39) may be provided on the photosensitive layer for the purpose of protecting the photosensitive layer. Materials used for the protective layer (39) include ABS resin, ACS resin, olefin-vinyl monomer copolymer, chlorinated polyether, aryl resin, phenol resin, polyacetal, polyamide, polyamideimide, polyacrylate, polyallylsulfone. , Polybutylene, polybutylene terephthalate, polycarbonate, polyethersulfone, polyethylene, polyethylene terephthalate, polyimide, acrylic resin, polymethylbenten, polypropylene, polyphenylene oxide, polysulfone, polystyrene, polyarylate, AS resin, butadiene-styrene copolymer, polyurethane , Resins such as polyvinyl chloride, polyvinylidene chloride, and epoxy resin. From the viewpoint of filler dispersibility, residual potential, and coating film defects, polycarbonate or polyarylate is particularly effective and useful.

Further, a filler material is added to the protective layer of the photoconductor for the purpose of improving the wear resistance.
As the solvent to be used, all solvents used in the charge transport layer 37 such as tetrahydrofuran, dioxane, toluene, dichloromethane, monochlorobenzene, dichloroethane, cyclohexanone, methyl ethyl ketone, and acetone can be used. However, a solvent having a high viscosity is preferable at the time of dispersion, but a solvent having high volatility is preferable at the time of coating. When there is no solvent satisfying these conditions, it is possible to use a mixture of two or more solvents having respective physical properties, which may have a great effect on filler dispersibility and residual potential. .

  Further, the protective layer may contain the benzidine compound of the present invention. Furthermore, the addition of the low molecular charge transport material or the polymer charge transport material mentioned in the charge transport layer (37) is effective and useful for reducing the residual potential and improving the image quality.

  As a method for forming the protective layer, conventional methods such as dip coating, spray coating, beat coating, nozzle coating, spinner coating, ring coating, etc. can be used. preferable.

  In the photoreceptor of the present invention, an intermediate layer can be provided between the photosensitive layer and the protective layer. In the intermediate layer, a binder resin is generally used as a main component. Examples of these resins include polyamide, alcohol-soluble nylon, water-soluble polyvinyl butyral, polyvinyl butyral, and polyvinyl alcohol. As a method for forming the intermediate layer, a generally used coating method as described above is employed. In addition, about 0.05-2 micrometers is suitable for the thickness of an intermediate | middle layer.

  In the present invention, in order to improve environmental resistance, in order to prevent a decrease in sensitivity and an increase in residual potential, oxidation is performed on each layer such as a charge generation layer, a charge transport layer, an undercoat layer, a protective layer, and an intermediate layer. Inhibitors, plasticizers, lubricants, UV absorbers and leveling agents can be added. Representative materials of these compounds are described below.

Examples of the antioxidant that can be added to each layer include, but are not limited to, the following.
(A) Phenolic compounds 2,6-di-t-butyl-p-cresol, butylated hydroxyanisole, 2,6-di-t-butyl-4-ethylphenol, n-octadecyl -3- (4'-hydroxy-3 ', 5'-di-tert-butylphenol), 2,2'-methylene-bis- (4-methyl-6-tert-butylphenol), 2,2'- Methylene-bis- (4-ethyl-6-tert-butylphenol), 4,4′-thiobis- (3-methyl-6-tert-butylphenol), 4,4′-butylidenebis- (3-methyl) -6-tert-butylphenol), 1,1,3-tris- (2-methyl-4-hydroxy-5-tert-butylphenyl) butane, 1,3,5-trimethyl-2,4,6- Tris (3,5-di-tert-butyl-4-hydroxybenzyl) benzene, te Lakis- [methylene-3- (3 ′, 5′-di-t-butyl-4′-hydroxyphenyl) propionate] methane, bis [3,3′-bis (4′-hydroxy-3′-t) -Butylphenyl) butyric acid] cricol ester, tocopherols and the like.

(B) Paraphenylenediamines N-phenyl-N′-isopropyl-p-phenylenediamine, N, N′-di-sec-butyl-p-phenylenediamine, N-phenyl-N-sec-butyl-p-phenylene Diamine, N, N′-di-isopropyl-p-phenylenediamine, N, N′-dimethyl-N, N′-di-t-butyl-p-phenylenediamine and the like.

(C) Hydroquinones 2,5-di-t-octylhydroquinone, 2,6-didodecylhydroquinone, 2-dodecylhydroquinone, 2-dodecyl-5-chlorohydroquinone, 2-t-octyl-5-methylhydroquinone, 2 -(2-octadecenyl) -5-methylhydroquinone and the like.

(D) Organic sulfur compounds Dilauryl-3,3′-thiodipropionate, distearyl-3,3′-thiodipropionate, ditetradecyl-3,3′-thiodipropionate, and the like.

(E) Organic phosphorus compounds Triphenylphosphine, tri (nonylphenyl) phosphine, tri (dinonylphenyl) phosphine, tricresylphosphine, tri (2,4-dibutylphenoxy) phosphine and the like.

Examples of the plasticizer that can be added to each layer include, but are not limited to, the following.
(A) Phosphate ester plasticizer Triphenyl phosphate, tricresyl phosphate, trioctyl phosphate, octyl diphenyl phosphate, trichloroethyl phosphate, cresyl diphenyl phosphate, tributyl phosphate, tri-2-ethylhexyl phosphate, Triphenyl phosphate etc.
(B) Phthalate ester plasticizers Dimethyl phthalate, diethyl phthalate, diisobutyl phthalate, dibutyl phthalate, diheptyl phthalate, di-2-ethylhexyl phthalate, diisooctyl phthalate, di-n-octyl phthalate, phthalate Dinonyl acid, diisononyl phthalate, diisodecyl phthalate, diundecyl phthalate, ditridecyl phthalate, dicyclohexyl phthalate, butyl benzyl phthalate, butyl lauryl phthalate, methyl oleyl phthalate, octyl decyl phthalate, dibutyl fumarate, dioctyl fumarate Such.
(C) Aromatic carboxylic acid ester plasticizers Trioctyl trimellitic acid, tri-n-octyl trimellitic acid, octyl oxybenzoate, and the like.
(D) Aliphatic dibasic ester plasticizer dibutyl adipate, di-n-hexyl adipate, di-2-ethylhexyl adipate, di-n-octyl adipate, adipic acid n-octyl-n-decyl , Diisodecyl adipate, dicapryl adipate, di-2-ethylhexyl azelate, dimethyl sebacate, diethyl sebacate, dibutyl sebacate, di-n-octyl sebacate, di-2-ethylhexyl sebacate, di-2 sebacate -Ethoxyethyl, dioctyl succinate, diisodecyl succinate, dioctyl tetrahydrophthalate, di-n-octyl tetrahydrophthalate and the like.
(E) Fatty acid ester derivatives butyl oleate, glycerin monooleate, methyl acetylricinoleate, pentaerythritol ester, dipentaerythritol hexaester, triacetin, tributyrin and the like.
(F) Oxyacid ester plasticizers Methyl acetyl ricinoleate, butyl acetyl ricinoleate, butyl phthalyl butyl glycolate, tributyl acetyl citrate and the like.
(G) Epoxy plasticizer Epoxidized soybean oil, epoxidized linseed oil, butyl epoxy stearate, decyl epoxy stearate, octyl epoxy stearate, benzyl epoxy stearate, dioctyl epoxy hexahydrophthalate, didecyl epoxy hexahydrophthalate, etc. .
(H) Dihydric alcohol ester plasticizers such as diethylene glycol dibenzoate and triethylene glycol di-2-ethylbutyrate.
(I) Chlorinated plasticizer Chlorinated paraffin, chlorinated diphenyl, chlorinated fatty acid methyl, methoxychlorinated fatty acid methyl and the like.
(J) Polyester plasticizer Polypropylene adipate, polypropylene sebacate, polyester, acetylated polyester and the like.
(K) Sulfonic acid derivatives p-toluenesulfonamide, o-toluenesulfonamide, p-toluenesulfoneethylamide, o-toluenesulfoneethylamide, toluenesulfone-N-ethylamide, p-toluenesulfone-N-cyclohexylamide and the like.
(L) Citric acid derivatives Triethyl citrate, triethyl acetylcitrate, tributyl citrate, tributyl acetylcitrate, tri-2-ethylhexyl acetylcitrate, acetylcitrate-n-octyldecyl, and the like.
(M) Others Terphenyl, partially hydrogenated terphenyl, camphor, 2-nitrodiphenyl, dinonylnaphthalene, methyl abietate and the like.

Examples of the lubricant that can be added to each layer include, but are not limited to, the following.
(A) Hydrocarbon compounds Liquid paraffin, paraffin wax, microwax, low-polymerized polyethylene and the like.
(B) Fatty acid compounds Lauric acid, myristic acid, palmitic acid, stearic acid, arachidic acid, behenic acid and the like.
(C) Fatty acid amide compounds Stearylamide, palmitylamide, oleinamide, methylenebisstearamide, ethylenebisstearamide and the like.
(D) Lower alcohol esters of ester compound fatty acids, polyhydric alcohol esters of fatty acids, fatty acid polyglycol esters, and the like.
(E) Alcohol compounds Cetyl alcohol, stearyl alcohol, ethylene glycol, polyethylene glycol, polyglycerol and the like.
(F) Metal soap Lead stearate, cadmium stearate, barium stearate, calcium stearate, zinc stearate, magnesium stearate and the like.
(G) Natural wax Carnauba wax, candelilla wax, beeswax, whale wax, ivotaro, montan wax and the like.
(H) Others Silicone compounds, fluorine compounds, etc.

Examples of the ultraviolet absorber that can be added to each layer include, but are not limited to, the following.
(A) Benzophenone series 2-hydroxybenzophenone, 2,4-dihydroxybenzophenone, 2,2 ′, 4-trihydroxybenzophenone, 2,2 ′, 4,4′-tetrahydroxybenzophenone, 2,2′-dihydroxy-4- Such as methoxybenzophenone.
(B) Salsylate type Phenyl salsylate, 2,4-di-t-butylphenyl-3,5-di-t-butyl-4-hydroxybenzoate, and the like.
(C) Benzotriazole series (2′-hydroxyphenyl) benzotriazole, (2′-hydroxy5′-methylphenyl) benzotriazole, (2′-hydroxy5′-methylphenyl) benzotriazole, (2′-hydroxy3) '-Tertiarybutyl 5'-methylphenyl) 5-chlorobenzotriazole (d) cyanoacrylate type ethyl-2-cyano-3,3-diphenyl acrylate, methyl 2-carbomethoxy 3 (paramethoxy) acrylate, and the like.
(E) Quencher (metal complex)
Nickel (2,2′thiobis (4-t-octyl) phenolate) normal butylamine, nickel dibutyldithiocarbamate, nickel dibutyldithiocarbamate, cobalt dicyclohexyldithiophosphate and the like.
(F) HALS (hindered amine)
Bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate, bis (1,2,2,6,6-pentamethyl-4-piperidyl) sebacate, 1- [2- [3- (3 5-di-t-butyl-4-hydroxyphenyl) propionyloxy] ethyl] -4- [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionyloxy] -2,2,6 6-tetramethylpyridine, 8-benzyl-7,7,9,9-tetramethyl-3-octyl-1,3,8-triazaspiro [4,5] undecane-2,4-dione, 4-benzoyloxy- 2,2,6,6-tetramethylpiperidine and the like.

Next, the electrophotographic method and the electrophotographic apparatus of the present invention will be described in detail with reference to the drawings.
FIG. 6 is a schematic diagram for explaining the electrophotographic process and the electrophotographic apparatus of the present invention, and the following examples also belong to the category of the present invention.
In FIG. 6, the photoreceptor (1) is provided with at least a photosensitive layer, and the outermost surface layer contains a filler. The photosensitive member (1) has a drum shape, but may be a sheet or an endless belt. A charging charger (3), a pre-transfer charger (7), a transfer charger (10), a separation charger (11), and a pre-cleaning charger (13) include a corotron, a scorotron, a solid state charger, and charging. A roller or the like is used, and all known means can be used.
As the transfer means, the above charger can be generally used. However, as shown in the figure, a combination of a transfer charger and a separation charger is effective.

Further, light sources such as an image exposure unit (5) and a charge removal lamp (2) include fluorescent lamps, tungsten lamps, halogen lamps, mercury lamps, sodium lamps, light emitting diodes (LEDs), semiconductor lasers (LD), and electroluminescence (EL). ) And other luminescent materials can be used. Various types of filters such as a sharp cut filter, a band pass filter, a near infrared cut filter, a dichroic filter, an interference filter, and a color temperature conversion filter can be used to irradiate only light in a desired wavelength range.
In addition to the steps shown in FIG. 6, the light source and the like are provided with a transfer step, a static elimination step, a cleaning step, a pre-exposure step, and the like using light irradiation, so that the photosensitive member is irradiated with light.

  The toner developed on the photoconductor (1) by the developing unit (6) is transferred to the transfer paper (9), but not all is transferred and remains on the photoconductor (1). Toner is also produced. Such toner is removed from the photoreceptor by the fur brush (14) and the blade (15). Cleaning may be performed only with a cleaning brush, and a known brush such as a fur brush or a mag fur brush is used as the cleaning brush.

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

  FIG. 7 shows another example of the electrophotographic process according to the present invention. The photosensitive member (21) has at least a photosensitive layer, and further contains a filler on the outermost surface layer. The photosensitive member (21) is driven by driving rollers (22a) and (22b) and charged by a charger (23), and a light source (24). Image exposure, development (not shown) by transfer, transfer using the charger (25), exposure before cleaning by the light source (26), cleaning by the brush 27, and charge removal by the light source (28) are repeated. In FIG. 7, the photoconductor (21) (of course, the support is translucent in this case) is irradiated with pre-cleaning exposure light from the support side.

  The above illustrated electrophotographic process is illustrative of an embodiment of the present invention, and of course other embodiments are possible. For example, in FIG. 7, the pre-cleaning exposure is performed from the support side, but this may be performed from the photosensitive layer side, or image exposure and neutralization light irradiation may be performed from the support side.

  On the other hand, the light irradiation process is illustrated as image exposure, pre-cleaning exposure, and static elimination exposure. In addition, a pre-transfer exposure, a pre-exposure of image exposure, and other known light irradiation processes are provided to light the photosensitive member. Irradiation can also be performed.

  The image forming means as described above may be fixedly incorporated in a copying apparatus, a facsimile, or a printer, but may be incorporated in these apparatuses in the form of a process cartridge. A process cartridge is a single device (part) that contains a photosensitive member and includes a charging unit, an exposure unit, a developing unit, a transfer unit, a cleaning unit, and a charge eliminating unit. There are many shapes and the like of the process cartridge, but a general example is shown in FIG. The photoreceptor (16) has at least a photosensitive layer on a conductive support and contains a filler in the outermost surface layer.

[Synthesis example]
Hereinafter, the present invention will be described in more detail, but the present invention is not limited to these examples. First, a synthesis example of the methylol compound of the general formula (1) used in the present invention will be described.

 [Synthesis Example 1]; (Production of Exemplified Compound 1 Synthesis of Intermediate Intermediate Aldehyde Compound Raw Material)

4,4′-diaminodiphenylmethane: 19.83 g, bromobenzene: 69.08 g, palladium acetate: 2.24 g, tert-butoxy sodium: 46.13 g, o-xylene: 250 ml are placed in a four-necked flask. Stir at room temperature under argon gas atmosphere. Tritial butyl phosphine: 8.09 g was added dropwise. Continue stirring at 80 ° C. for 1 hour and at reflux for 1 hour. Dilute with toluene, add magnesium sulfate, activated clay, silica gel and stir.
Filtration, washing, and concentration were performed to obtain a crystalline product. The product was dispersed in methanol, filtered, washed and dried to obtain the desired product. (Yield 45.73 g, pale yellow powder, infrared absorption spectrum (KBr tablet method) is shown in FIG. 9). In the figure, the horizontal axis indicates the wave number (cm ⁻¹ ), and the vertical axis indicates the transmittance (%).

 [Synthesis Example 2]; (Production of Exemplified Compound 1 Synthesis of Intermediate Aldehyde Compound)

Intermediate raw material: 30.16 g, N-methylformanilide: 71.36 g, o-dichlorobenzene: 400 ml are put into a four-necked flask. Stir at room temperature under argon gas atmosphere.
Phosphorus oxychloride: 82.01 g was added dropwise. The temperature was raised to 80 ° C. and stirred. Zinc chloride: 32.71 g was added dropwise. Stirring is performed at 80 ° C. for about 10 hours, and stirring is continued at 120 ° C. for about 3 hours. A potassium hydroxide aqueous solution was added to conduct a hydrolysis reaction. Extraction with dichloromethane, dehydration with magnesium sulfate, and adsorption treatment with activated clay. Filtration, washing, and concentration were performed to obtain a crystalline product.
Silica gel column purification (toluene / ethyl acetate = 8/2) was performed and isolated. The obtained crystal was recrystallized from methanol / ethyl acetate to obtain the desired product. (Yield 27.80 g, yellow powder, infrared absorption spectrum is shown in FIG. 10)

 [Synthesis Example 3]; (Synthesis of Exemplified Compound 1)

  Intermediate aldehyde compound: 12.30 g, ethanol: 150 ml are placed in a four-necked flask. The mixture was stirred at room temperature, and 3.63 g of sodium borohydride was dropped. Continue stirring for 4 hours. The mixture was extracted with ethyl acetate, dehydrated with magnesium sulfate, and adsorbed with activated clay and silica gel. An amorphous substance was obtained by filtration, washing and concentration. The product was dispersed in n-hexane and taken out by filtration, washing and drying to obtain the desired product. (Yield 12.0 g, light yellowish white amorphous, infrared absorption spectrum is shown in FIG. 11)

 [Synthesis Example 4]; (Production of Exemplified Compound 2 Synthesis of Intermediate Aldehyde Compound Raw Material)

4,4'-diaminodiphenyl ether: 20.02 g, bromobenzene: 69.08 g, palladium acetate: 0.56 g, tert-butoxy sodium: 46.13 g, o-xylene: 250 ml are placed in a four-necked flask. Stir at room temperature under argon gas atmosphere.
Tritertiary butylphosphine: 2.02 g was added dropwise. Continue stirring at 80 ° C. for 1 hour and at reflux for 1 hour. Dilute with toluene, add magnesium sulfate, activated clay, silica gel and stir. Filtration, washing, and concentration were performed to obtain a crystalline product. The product was dispersed in methanol, filtered, washed and dried to obtain the desired product. (Yield 43.13 g, light brown powder, infrared absorption spectrum is shown in FIG. 12)

 [Synthesis Example 5]; (Production of Exemplified Compound 2 Synthesis of Intermediate Aldehyde Compound)

Intermediate raw material: 30.27 g, N-methylformanilide: 71.36 g, o-dichlorobenzene: 300 ml are put into a four-necked flask. Stir at room temperature under argon gas atmosphere.
Phosphorus oxychloride: 82.01 g was added dropwise. The temperature was raised to 80 ° C. and stirred. Zinc chloride: 16.36 g was added dropwise. Stirring was performed at 80 ° C for 1 hour, stirring was continued at 120 ° C for 4 hours, and 140 ° C for 3 hours. A potassium hydroxide aqueous solution was added to conduct a hydrolysis reaction. Extract with toluene solvent, add magnesium sulfate, filter, wash, concentrate. Column purification was performed with toluene / ethyl acetate, and crystals were obtained after concentration. The product was dispersed in methanol, filtered, washed and dried to obtain the desired product. (Yield 14.17 g, pale yellow powder, infrared absorption spectrum is shown in FIG. 13)

 [Synthesis Example 6]; (Synthesis of Exemplified Compound 2)

  Intermediate aldehyde compound: 6.14 g 6.14 g, ethanol: 75 ml are placed in a four-necked flask. The mixture was stirred at room temperature and 1.82 g of sodium borohydride was added. Continue stirring for 7 hours. The mixture was extracted with ethyl acetate, dehydrated with magnesium sulfate, and adsorbed with activated clay and silica gel. An amorphous substance was obtained by filtration, washing and concentration. Disperse with n-hexane, take out by filtration, washing and drying to obtain the desired product. (Yield 5.25 g, white amorphous, infrared absorption spectrum is shown in FIG. 14)

 [Synthesis Example 7]; (Production of Exemplified Compound 3 Synthesis of Intermediate Aldehyde Compound Raw Material)

  Diphenylamine: 22.33, dibromostilbene: 20.28 g, palladium acetate: 0.336 g, tert-butoxy sodium: 13.84 g, o-xylene: 150 ml are placed in a four-necked flask. Stir at room temperature under argon gas atmosphere. Tritertiary butylphosphine: 1.22 g was added dropwise. Continue stirring at 80 ° C. for 1 hour and at reflux for 2 hours. Dilute with toluene, add magnesium sulfate, activated clay, silica gel and stir. Filtration, washing, and concentration were performed to obtain a crystalline product. The product was dispersed in methanol, filtered, washed and dried to obtain the desired product. (Yield 29.7 g, yellow powder, infrared absorption spectrum is shown in FIG. 15)

 [Synthesis Example 8]; (Production of Exemplary Compound 3 Synthesis of Intermediate Aldehyde Compound)

  Dehydrated dimethylformaldehyde: 33.44 g and dehydrated toluene: 84.53 g are placed in a four-necked flask. Stir in an argon gas atmosphere and ice-water bath. Slowly drop 63.8 g of phosphorus oxychloride. Continue stirring for about 1 hour. Intermediate raw material: 26.76 g of dehydrated toluene: 106 g A solution was slowly added dropwise. Stirring is performed at 80 ° C. for 1 hour, and stirring is continued for 5 hours at reflux. A potassium hydroxide aqueous solution was added to conduct a hydrolysis reaction. Extract with toluene, dehydrate with magnesium sulfate, and concentrate. Isolated by column purification (toluene / ethyl acetate = 8/2). The product was dispersed in methanol and taken out by filtration, washing and drying to obtain the desired product. (Yield 16.66 g, orange powder, infrared absorption spectrum is shown in FIG. 16)

 [Synthesis Example 9]; (Synthesis of Exemplified Compound 3)

  Intermediate aldehyde compound: 6.54 g6, ethanol: 75 ml is placed in a four-necked flask. The mixture was stirred at room temperature and 1.82 g of sodium borohydride was added. Continue stirring for 4 hours. The mixture was extracted with ethyl acetate, dehydrated with magnesium sulfate, and adsorbed with activated clay and silica gel. An amorphous substance was obtained by filtration, washing and concentration. Disperse with n-hexane, take out by filtration, washing and drying to obtain the desired product. (Yield 2.30 g, yellow amorphous, infrared absorption spectrum is shown in FIG. 17)

 [Synthesis Example 10]; (Production of Exemplified Compound 4 Synthesis of Raw Material for Intermediate Aldehyde Compound)

  2,2'-ethylenedianiline: 21.23 g, bromobenzene: 75.36 g, palladium acetate: 0.56 g, tert-butoxy sodium: 46.13 g, o-xylene: 250 ml are placed in a four-necked flask. Stir in an argon gas atmosphere and room temperature. Add dropwise 2.03 g of tributyl phosphine. Continued at reflux for 8 hours. Dilute with toluene, add magnesium sulfate and activated clay, and stir at room temperature. Filtration, washing, and concentration were performed to obtain a crystalline product. The product was dispersed in methanol, filtered, washed and dried to obtain the desired product. (Yield 47.65 g, light brown powder, infrared absorption spectrum is shown in FIG. 18)

 [Synthesis Example 11]; (Production of Exemplified Compound 4 Synthesis of Intermediate Aldehyde Compound)

  Intermediate raw material donor: 31.0 g, N-methylformanilide: 71.36 g, o-chlorobenzene: 400 ml are placed in a four-necked flask. Stir in an argon gas atmosphere and room temperature. Phosphorus oxychloride: 82.01 g was slowly added dropwise, and the temperature was raised to 80 ° C. Zinc chloride: 32.71 g was added and continued at 80 ° C. for 1 hour and at 120 ° C. for about 24 hours. A potassium hydroxide aqueous solution was added to conduct a hydrolysis reaction. Diluted with toluene, then washed with water, the oil layer was dehydrated with magnesium chloride, adsorbed with activated clay and silica gel, filtered, washed and concentrated to obtain the desired product. (Yield 22.33 g, yellow liquid, infrared absorption spectrum is shown in FIG. 19)

 [Synthesis Example 12]; (Synthesis of Exemplified Compound 4)

  Intermediate aldehyde compound: 9.43 g, ethanol: 100 ml are placed in a four-necked flask. The mixture was stirred at room temperature, and sodium borohydride: 2.72 g was dropped. Continue stirring for 7 hours. The mixture was extracted with ethyl acetate, dehydrated with magnesium sulfate, and adsorbed with activated clay and silica gel. An amorphous substance was obtained by filtration, washing and concentration. The product was dispersed in n-hexane and taken out by filtration, washing and drying to obtain the desired product. (Yield 8.53 g, white amorphous, infrared absorption spectrum is shown in FIG. 20)

According to the explanation given above, the methylol of the present invention represented by the general formula (1) is obtained by using the aldehyde compound represented by the general formula (2) to be synthesized as a production intermediate and reducing it. It can be seen that the compound is easily produced.
Furthermore, the above-mentioned other exemplified compounds 2 to 6 are also easily produced by the above reaction.

[Example of electrophotographic photoreceptor]
EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated, this invention is not restrict | limited by an Example. All parts are parts by weight.

<Evaluation of charge transportability>
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 an aluminum plate in sequence, an undercoat layer of 0.3 μm; Six types of photoconductors (1) to (6) were prepared by forming a 3 μm charge generation layer and a 20 μm charge transport layer.
In addition, the methylol compounds 1 to 4 of the present invention and the comparative compounds (I) and (II) synthesized in the synthesis examples were used as the components of the charge transport layer coating solution in the six types of photoreceptors, respectively.

<Coating liquid for undercoat layer>
Polyamide resin (CM-8000: manufactured by Toray Industries, Inc.): 2 parts Methanol: 49 parts Butanol: 49 parts

<Coating liquid for charge generation layer>
Bisazo pigment having the following structural formula: 2.5 parts polyvinyl butyral (XYHL: manufactured by UCC): 0.5 parts cyclohexanone: 200 parts methyl ethyl ketone: 80 parts

<Coating liquid for charge transport layer: (1)>
Bisphenol Z polycarbonate (Panlite TS-2050, manufactured by Teijin Chemicals Ltd.): 10 parts charge transporting compound (exemplified methylol compound (I) shown in Table 1: 10 parts tetrahydrofuran: 80 parts tetrahydrofuran solution of 1% silicone oil (KF- 50-100CS, manufactured by Shin-Etsu Chemical Co., Ltd.): 0.2 parts

  Photoreceptor No (2) was produced in the same manner as in Example 1 except that the exemplified methylol compound 1 in Example 1 was changed to the exemplified methylol compound 2.

  Photoreceptor No (3) was produced in the same manner as in Example 1, except that the exemplified methylol compound 1 in Example 1 was changed to the exemplified methylol compound 3.

  Photoreceptor No (4) was produced in the same manner as in Example 1 except that the exemplified methylol compound 1 in Example 1 was changed to the exemplified methylol compound 4.

[Comparative Example 1]
Photoreceptor No (5) was produced in the same manner as in Example 1 except that the exemplified methylol compound 1 in Example 1 was changed to the compound (I) shown below.

[Comparative Example 2]
Photoreceptor No (6) was produced in the same manner as in Example 1 except that the exemplified methylol compound 1 in Example 1 was changed to the compound (II) shown below.

With respect to the photoreceptors (1) to (6) obtained as described above, a commercially available electrostatic copying paper testing apparatus [EPA-8200 type manufactured by Kawaguchi Electric Mfg. Co., Ltd.] was used to charge transport from half-exposure amount and residual potential. Evaluated.
The charge transportability was evaluated from the half-exposure amount and the residual potential using a commercially available electrostatic copying paper testing apparatus [type EPA-8200 manufactured by Kawaguchi Electric Co., Ltd.]. That is, after charging to −800 V by −6 kV corona discharge in a dark place, tungsten lamp light is irradiated so that the illuminance on the surface of the photosensitive member becomes 4.5 lux, and the potential is reduced to ½. Time (seconds) was obtained, and half-exposure amount E1 / 2 (lux · sec) was calculated. Further, the residual potential (−V) after 30 seconds of exposure was determined. The smaller the half-exposure amount, the better the sensitivity, and the smaller the residual potential, the fewer charge traps.

  From the above evaluation results, the photoconductors (1) to (4) using the methylol compound of the present invention compared to the comparative photoconductor using the charge transporting compound (I) having no methylol group, which is a known material. It can be seen that is not inferior, has a small half-exposure dose, has good sensitivity, has no residual potential, has no charge trap, and exhibits good charge transport properties.

  An electrophotographic photoreceptor No (7) was prepared and evaluated in the same manner as in Example 1 except that the charge transport layer coating solution in Example 1 was changed to one having the following composition. The results are shown in Table 3.

◎ Charge transport layer coating solution, polycarbonate resin Z polycarbonate (manufactured by Teijin Chemicals): 2 parts 1 benzidine compound: 1 part Charge transport material of the following structural formula: 1 part Tetrahydrofuran: 16 parts

  In Example 5, an electrophotographic photoreceptor No (8) was prepared and evaluated in the same manner as in Example 5 except that the charge transport material was changed to the compound (III) shown below. The results are also shown in Table 3.

In Example 5, the electrophotographic photosensitive member No (9) was prepared in the same manner as in Example 5 except that the charge transport material and binder resin contained in the charge transport layer were changed to the following compound (IV). Prepared and evaluated. The results are also shown in Table 3. The weight average molecular weight in terms of polystyrene determined by gel permeation chromatography of the polymer charge transport material was 52200.
Polymer charge transport material of the following structural formula: 3 parts

In Example 5, the electrophotographic photoreceptor No (10) was prepared in the same manner as in Example 5 except that the charge transporting material and binder resin contained in the charge transporting layer were changed to the compound (V) shown below. Prepared and evaluated. The results are also shown in Table 3. The weight average molecular weight in terms of polystyrene determined by gel permeation chromatography of the polymer charge transport material was 50800.
Polymer charge transport material having the following structural formula (average weight molecular weight: 50800): 3 parts

In Example 5, electrophotographic photoreceptor No (11) was prepared and evaluated in the same manner as in Example 5 except that the binder resin was changed to the following material. The results are also shown in Table 3.
Polyarylate resin (U polymer, manufactured by Unitika): 1 part

<Image evaluation>
The photoconductors (1) to (11) obtained as described above were mounted on an electrophotographic process cartridge, the charging method was a corona charging method (scorotron type), and the image exposure light source was a 655 nm semiconductor laser (LD). The dark part potential was set to 800 (-V) with a Ricoh imagio MF2200 remodeling machine, and then a repeated test equivalent to printing a total of 100,000 sheets was continuously performed. At that time, the initial image and the image after the repeated test were evaluated. Further, the bright part potential after the initial and repeated tests was also measured. The results are shown in Table 4.

  From the above evaluation results, it was confirmed that the bright portion potential increase was small even after printing 100,000 sheets, and that the photoconductor containing the methylol compound of the present invention can stably obtain a high-quality image.

(About FIGS. 1-5)
31 Conductive Support 33 Photosensitive Layer 35 Charge Generation Layer 37 Charge Transport Layer 39 Protective Layer (Regarding FIG. 6)
DESCRIPTION OF SYMBOLS 1 Photoconductor 2 Static elimination lamp 3 Charger 4 Eraser 5 Image exposure part 6 Developing unit 7 Pre-transfer charger 8 Registration roller 9 Transfer paper 10 Transfer charger 11 Separation charger 12 Separation claw 13 Pre-cleaning charger 14 Fur brush 15 Cleaning blade (FIG. 7)
21 Photoconductor 22a Drive roller 22b Drive roller 23 Charger 24 Image exposure light source 25 Charger 26 Pre-cleaning exposure light source 27 Cleaning brush 28 Static elimination light source (about FIG. 8)
16 Photoconductor 17 Charger charger 18 Cleaning brush 19 Image exposure unit 20 Developing roller

JP 62-30255 A JP-A-63-225660 JP 58-159536 A

Journal of Electrophotographic Society, 25 (3), 16 (1986)

Claims (12)

An electrophotographic photosensitive member, wherein a photosensitive layer containing a methylol compound represented by the following general formula (1) is provided on a conductive support.

(In the formula, X represents —O—, —CH ₂ —, —CH═CH—, —CH ₂ CH ₂ —). An electrophotographic photoreceptor, wherein a photosensitive layer containing a methylol compound represented by the following general formula (1) and a charge transport material is provided on a conductive support.

(In the formula, X represents —O—, —CH ₂ —, —CH═CH—, —CH ₂ CH ₂ —). 3. The electrophotographic photoreceptor according to claim 2, wherein the charge transport material is a stilbene compound represented by the following general formula (2).

(Wherein n represents an integer of 0 or 1, R ¹ represents a hydrogen atom, an alkyl group or a substituted or unsubstituted phenyl group, Ar ¹ represents a substituted or unsubstituted aromatic hydrocarbon group, and R ⁵ represents It represents a C 1-4 alkyl group, or a substituted or unsubstituted aromatic hydrocarbon group, and Ar ¹ and R ⁵ may form a ring together.

Represents a 9-anthryl group or a substituted or unsubstituted carbazolyl group, wherein R ² represents a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom or

Wherein R ³ and R ⁴ represent a substituted or unsubstituted aromatic hydrocarbon group, R ³ and R ⁴ may be the same or different and may form a ring, and m represents 1 Represents an integer of ˜3, and when 2 or more, R ² may be the same or different. When n is 0, A and R ¹ may form a ring together. ) 3. The electrophotographic photoreceptor according to claim 2, wherein the charge transport material is an aminobiphenyl compound represented by the following general formula (3).

(Wherein R ⁶ , R ⁸ and R ⁹ are a hydrogen atom, an amino group, an alkoxy group, a thioalkoxy group, an aryloxy group, a methylenedioxy group, a substituted or unsubstituted alkyl group, a halogen atom, or a substituted or unsubstituted group. R ⁷ represents a hydrogen atom, an alkoxy group, a substituted or unsubstituted alkyl group or a halogen atom, and k, l, m and n are integers of 1, 2, 3 or 4, When R is an integer of 2, 3 or 4, the R ⁶ , R ⁷ , R ⁸ and R ⁹ may be the same or different.)   The electrophotographic photosensitive member according to claim 2, wherein the charge transport material is a polymer charge transport material. 6. The electrophotographic photosensitive member according to claim 5, wherein the polymer type charge transport material is a material represented by the following general formula (4).

(Wherein R ₁₇ and R ₁₈ represent substituted or unsubstituted aromatic ring groups, Ar ₁ , Ar ₂ and Ar ₃ represent the same or different aromatic ring groups. K and j represent compositions, and 0.1 ≦ k ≦ 1, 0 ≦ j ≦ 0.9, n represents the number of repeating units and is an integer of 5 to 5000. X is represented by an aliphatic divalent group, a cycloaliphatic divalent group, or the following general formula. Represents a divalent group.)

(In the formula, R ₁₀₁ and R ₁₀₂ each independently represents a substituted or unsubstituted alkyl group, an aromatic ring group or a halogen atom. L and m are integers of 0 to 4, Y is a single bond and 1 carbon atom. To 12 linear, branched or cyclic alkylene groups, —O—, —S—, —SO—, —SO ₂ —, —CO—, —CO—O—Z—O—CO— Z represents an aliphatic divalent group) or

(Wherein, a represents an integer of 1 to 20, b represents an integer of 1 to 2000, R ₁₀₃ and R ₁₀₄ represent a substituted or unsubstituted alkyl group or aryl group). Here, R ₁₀₁ and R ₁₀₂ , R ₁₀₃ and R ₁₀₄ may be the same or different. ) An electrophotographic photoreceptor, wherein the polymer charge transporting material is a material represented by the following general formula (5).

(In the formula, Ar ₄ , Ar ₅ , Ar ₆ , Ar ₇ and Ar ₈ represent a substituted or unsubstituted aromatic ring group, Z represents an aromatic ring group or —Ar ₉ —Za—Ar ₉ —, and Ar ₉ represents a substituted group. Or an unsubstituted aromatic ring group, Za represents O, S or an alkylene group, R and R ′ represent a linear or branched alkylene group, m represents 0 or 1, k, j, n and X represent Same as formula.)   The electrophotographic photosensitive member according to claim 1, wherein at least charging, image exposure, development, and transfer are repeatedly performed on the electrophotographic photosensitive member, wherein the electrophotographic photosensitive member is the electrophotographic photosensitive member according to claim 1. An electrophotographic forming method.   9. The electrophotographic forming method according to claim 8, wherein electrostatic latent image writing on the photosensitive member in the image exposure is performed by a digital method.   The electrophotographic photosensitive member according to any one of claims 1 to 7, wherein the electrophotographic photosensitive member comprises at least a charging unit, an image exposing unit, a developing unit, a transfer unit, and an electrophotographic photosensitive member. An electrophotographic apparatus characterized by being configured.   11. The electrophotographic apparatus according to claim 10, wherein the electrostatic latent image writing on the photosensitive member by the image exposure unit is a digital method.   The electrophotographic photosensitive member is integrally supported including at least one member selected from the group consisting of a charging unit, an image exposing unit, a developing unit, a transferring unit, a cleaning unit, and a neutralizing unit, and can be attached to and detached from the main body of the electrophotographic apparatus. 8. A process cartridge for an electrophotographic apparatus according to claim 1, wherein the electrophotographic photoreceptor is the electrophotographic photoreceptor according to any one of claims 1 to 7.

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