JP2008152248A - Electrophotographic photoreceptor, electrophotographic photoreceptor cartridge and image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electrophotographic photoreceptor which ensures a sufficiently low residual potential and has properties hardly affected by exposure to external light. <P>SOLUTION: In the electrophotographic photoreceptor, a photosensitive layer contains a compound represented by general formula (1) and a compound represented by general formula (2), wherein a content ratio between the compounds in the photosensitive layer is defined by the formula (A): 80>(the mass of the compound represented by the general formula (1)/the mass of the compound represented by the general formula (2))>0. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an electrophotographic photosensitive member used for a copying machine, a printer, and the like, an electrophotographic photosensitive member cartridge using the same, and an image forming apparatus.

  C. F. The electrophotographic technology invented by Carlson's invention is not limited to the copier field, but also in the field of various printers, facsimiles, etc. It is also widely used as a multifunction device, and it is expanding greatly.

  For photoconductors that are the core of electrophotographic technology, photoconductors that use organic photoconductive materials, which have the advantages of being non-polluting, easy to form and easy to manufacture, are mainly used. Is used. Above all, a so-called multilayer photoreceptor in which a charge generation layer and a charge transport layer are laminated can provide a more sensitive photoreceptor, a wide range of material selection, and a highly safe photoreceptor. Since it is highly productive and relatively advantageous in terms of cost, it is now the mainstream of photoconductors and is produced in large quantities.

  By the way, with respect to the image forming technique, digitization is rapidly progressing in order to obtain a high-quality image and to store an input image or freely edit it. In the past, digital image formation has been limited to laser printers, LED printers, and some color laser copiers that are output devices of word processors and personal computers. Digitization was almost completely achieved even in the field of ordinary copying machines where mainstream image formation was the mainstream.

When such digital image formation is performed in electrophotography, laser light or LED light is mainly used for optical input of digital signals to the photosensitive member. Currently, the most frequently used transmission wavelength of input light is near-infrared light of 780 nm or 660 nm or long-wavelength light close thereto.
The first requirement for a photoreceptor used for digital image formation is sensitivity to these long-wavelength light. In addition, various basic characteristics such as sufficient chargeability, low dark decay after charging, low residual potential, and good stability during repeated use of these characteristics are also required. .

On the other hand, there are characteristics required from a practical viewpoint, and a typical one is light resistance.
Usually, the photoreceptor is used in a state where it is shielded from light inside a copying machine or printer. However, when assembling the machine, when a paper jam occurs when the machine is used, and when the paper is taken out of the machine, or when the photoconductor unit has reached the end of its life and is to be replaced, the photoconductor is inevitably exposed to external light ( Exposure to fluorescent light and sunlight).

The light intensity of the external light is much stronger than the exposure intensity for image formation in the machine and contains a lot of short wavelength light, which causes great damage to the photoconductor.
This is because exposure of the photoreceptor to light generates a large amount of charge traps inside the photoreceptor, and in many cases leads to a decrease in charging potential and a significant increase in residual potential.

  Until now, in order to prevent damage from external light, for example, a yellow light with less influence was used for lighting during assembly of the machine, or light exposure to the photosensitive member was minimized when opening the inside of the machine, so that light was blocked. It has been dealt with by providing a board. On the other hand, for example, in order to suppress an increase in residual potential upon exposure to light, studies have been made such as adding an electron-withdrawing substance or an antioxidant to the charge transport layer. . However, the effect of preventing the residual potential from rising was not sufficient. In addition, even if the increase in residual potential after light exposure is suppressed, side effects on other characteristics such as increase in residual potential during normal use, increase in residual potential during repeated use, and decrease in chargeability are increased. There was a problem.

Various characteristics of the photoconductor including the residual potential largely depend on the charge generation material and the charge transport material in the photoconductor. For this reason, for the purpose of improving the performance of the photoconductor, studies on charge generating materials and charge transporting materials contained in the photoconductor have been widely conducted. Among them, it is known that a charge transport material having a plurality of double bonds introduced therein described in Patent Documents 1 to 4 exhibits a very low residual potential.
JP-A-9-244278 Japanese Patent Laid-Open No. 10-312072 JP 7-173112 A JP-A-8-295655

  However, the charge transport materials as described in Patent Documents 1 to 4 have insufficient properties such as light resistance, ozone resistance, liquid storage characteristics, and compatibility, and are still satisfactory. Is not obtained.

  The present invention has been made in view of the above-described problems. That is, an object of the present invention is to provide an electrophotographic photosensitive member having a sufficiently low residual potential and having little influence on the characteristics even when exposed to external light, and an electron using the electrophotographic photosensitive member A photographic photosensitive member cartridge and an image forming apparatus are provided.

  As a result of intensive studies to achieve a low residual potential, the present inventors have included a compound having a specific structure in a specific ratio in the photosensitive layer without affecting various characteristics of the photoconductor. The inventors have found that the increase in the residual potential of the photoconductor upon exposure to light can be greatly improved, and have completed the present invention.

That is, the first aspect of the present invention is an electrophotographic photoreceptor having a photosensitive layer on a conductive support, wherein the photosensitive layer is represented by the following general formula (1) and the following general formula (2). The content ratio of the compound represented by the general formula (1) and the compound represented by the general formula (2) in the photosensitive layer is represented by the following formula (A). It is an object of the present invention to provide a characteristic electrophotographic photosensitive member to solve the above problems.
80> (mass of compound represented by general formula (1) / mass of compound represented by general formula (2))> 0 (A)

（一般式（１）および（２）中、Ｒ^１〜Ｒ^５は、水素原子、置換基を有していてもよいアルキル基、又は置換基を有していてもよいアリール基を表し、Ｘは、炭素数２０〜６０の有機残基を表し、ｎは０〜２の整数を表す。）

(In the general formulas (1) and (2), R ^{1 to} R ⁵ represent a hydrogen atom, an alkyl group which may have a substituent, or an aryl group which may have a substituent, and X Represents an organic residue having 20 to 60 carbon atoms, and n represents an integer of 0 to 2.

A second aspect of the present invention is an electrophotographic photoreceptor having a photosensitive layer on a conductive support, wherein the photosensitive layer is represented by the following general formula (1) and the following general formula (2). The content ratio of the compound represented by the general formula (1) and the compound represented by the general formula (2) in the photosensitive layer is represented by the following formula (B). An electrophotographic photosensitive member is provided to solve the above problems.
80> (peak area of the compound represented by the general formula (1) in high performance liquid chromatography measurement (detection light wavelength 254 nm) / the compound represented by the general formula (2) in high performance liquid chromatography measurement (detection light wavelength 254 nm) Peak area)> 0 (B)

（一般式（１）および（２）中、Ｒ^１〜Ｒ^５は、水素原子、置換基を有していてもよいアルキル基、又は置換基を有していてもよいアリール基を表し、Ｘは、炭素数２０〜６０の有機残基を表し、ｎは０〜２の整数を表す。）

(In the general formulas (1) and (2), R ^{1 to} R ⁵ represent a hydrogen atom, an alkyl group which may have a substituent, or an aryl group which may have a substituent, and X Represents an organic residue having 20 to 60 carbon atoms, and n represents an integer of 0 to 2.

A third aspect of the present invention is an electrophotographic photoreceptor having a photosensitive layer on a conductive support, wherein the photosensitive layer is represented by the following general formula (1) and the following general formula (2). The content ratio of the compound represented by the general formula (1) and the compound represented by the general formula (2) in the photosensitive layer is represented by the following formula (C). An electrophotographic photosensitive member is provided to solve the above problems.
80> (Molecular ion peak intensity of compound represented by general formula (1) in mass spectrum measurement / Molecular ion peak intensity of compound represented by general formula (2) in mass spectrum measurement)> 0 (C)

（一般式（１）および（２）中、Ｒ^１〜Ｒ^５は、水素原子、置換基を有していてもよいアルキル基、又は置換基を有していてもよいアリール基を表し、Ｘは、炭素数２０〜６０の有機残基を表し、ｎは０〜２の整数を表す。）

(In the general formulas (1) and (2), R ^{1 to} R ⁵ represent a hydrogen atom, an alkyl group which may have a substituent, or an aryl group which may have a substituent, and X Represents an organic residue having 20 to 60 carbon atoms, and n represents an integer of 0 to 2.

  In the first to third aspects, the photosensitive layer preferably contains phthalocyanine having a total chlorine content (elements) of 0.6% by mass or less.

  In the first to third aspects, the electrophotographic photosensitive member exhibits a diffraction peak at a Bragg angle (2θ ± 0.2 °) of 27.3 ° in the X-ray diffraction spectrum, or 9.3 °. It is also preferable to contain oxytitanium phthalocyanine which shows diffraction peaks at 10.6 ° and 26.3 °.

  According to a fourth aspect of the present invention, there is provided an electrophotographic photosensitive member according to the first to third aspects (including each preferred aspect), a charging unit for charging the electrophotographic photosensitive member, and the charged electron. An image forming apparatus comprising: an exposure unit that exposes a photographic photosensitive member to form an electrostatic latent image; and a developing unit that develops the electrostatic latent image formed on the electrophotographic photosensitive member. It provides and solves the said subject.

  According to a fifth aspect of the present invention, there is provided an electrophotographic photosensitive member according to the first to third aspects (including each preferred aspect), a charging portion for charging the electrophotographic photosensitive member, and the charged electrophotographic image. At least one of an exposure unit that exposes the photosensitive member to form an electrostatic latent image and a developing unit that develops the electrostatic latent image formed on the electrophotographic photosensitive member is provided. An electrophotographic photosensitive member cartridge is provided to solve the above problems.

  In the electrophotographic photoreceptor of the present invention, the surface potential after exposure is sufficiently low by containing the compounds represented by the general formulas (1) and (2) in a specific ratio in the photosensitive layer. At the same time, fatigue due to external light of the electrophotographic photosensitive member can be suppressed extremely small. That is, according to the present invention, it is possible to obtain an electrophotographic photoreceptor in which a low residual potential and light resistance are ensured at the same time. Further, by using an electrophotographic photosensitive member cartridge and an image forming apparatus using this electrophotographic photosensitive member, it is possible to obtain a high-quality output image, and furthermore, even when exposed to external light, the quality fluctuation is extremely high. Fewer images can be obtained.

  Such an operation and a gain of the present invention will be clarified from the best mode for carrying out the invention described below.

  The electrophotographic photoreceptor of the present invention is characterized in that the photosensitive layer contains compounds represented by the following general formulas (1) and (2).

In general formulas (1) and (2), R ^{1 to} R ⁵ represent a hydrogen atom, an alkyl group that may have a substituent, or an aryl group that may have a substituent.

The alkyl group constituting R ^{1 to} R ⁵ is not particularly limited as long as it is not contrary to the gist of the present invention. Examples thereof include a methyl group, an ethyl group, a propyl group, an isopropyl group, a pentyl group, an isopentyl group, and a neopentyl group. Group, 1-methylbutyl group, 1-methylheptyl group, dodecyl group, hexadecyl group, octadecyl group and the like. Among these, an alkyl group having 8 or less carbon atoms is preferable.

The aryl group constituting R ^{1 to} R ⁵ is not particularly limited as long as it does not contradict the gist of the present invention, but the number of aromatic rings is usually 1 or more, preferably 5 or less, more preferably 3 or less. A substituent is preferred. When each aryl group has two or more aromatic rings, they may be condensed with each other. Further, one or two or more non-aromatic rings may be further condensed to one or two or more aromatic rings. The carbon number of the aryl group is usually 18 or less, preferably 14 or less.

The type of substituent that R ^{1 to} R ⁵ may have is not particularly limited unless it is contrary to the gist of the present invention. Examples thereof include a methyl group, an ethyl group, a propyl group, an isopropyl group, and a pentyl group. Alkyl groups such as isopentyl group, neopentyl group, 1-methylbutyl group, 1-methylheptyl group, dodecyl group, hexadecyl group and octadecyl group; aryl groups such as phenyl group and naphthyl group; aralkyl groups such as benzyl group and phenethyl group Alkoxy groups such as methoxy group and ethoxy group; hydroxy group; nitro group; halogen atom and the like. These exemplified substituents may be further substituted with these exemplified substituents. R ^{1 to} R ⁵ may each have a plurality of these substituents. However, the number of substituents each of R ^{1 to} R ⁵ has is usually 2 or less, preferably 1 or less. In addition, the total number of substituents that R ^{1 to} R ⁵ have is usually 8 or less, and preferably 6 or less.

The carbon number of the substituent that each R ^{1 to} R ⁵ may have is usually 10 or less, particularly 8 or less, and more preferably 4 or less, because the residual potential tends to increase if the carbon number of the substituent is too large. In view of charge mobility and electrical characteristics, unsubstituted is more preferable. In addition, when the above-mentioned exemplary substituent is further substituted by the above-mentioned exemplary substituent, it is preferable that carbon number of the whole substituent containing them satisfies the said range.

Specifically, R ^{1 to} R ³ are preferably an aryl group having 6 or less carbon atoms, an alkyl group, or a hydrogen atom, and particularly preferably a hydrogen atom. R ⁴ and R ⁵ are specifically preferably an aryl group having 10 or less carbon atoms, an alkyl group, or a hydrogen atom. Among them, at least one of R ⁴ and R ⁵ is preferably an aryl group having 10 or less carbon atoms, and more preferably a phenyl group. More preferably, R ⁴ is a phenyl group and R ⁵ is a hydrogen atom.

  In general formula (1) and general formula (2), n represents the integer of 0-2. From the viewpoint of charge mobility, n is preferably 1 or 2, but from the viewpoint of ozone resistance, n is preferably 0 or 1. In consideration of both charge mobility and ozone resistance, n is more preferably 1.

  X represents an organic residue having 20 to 60 carbon atoms. In order to have a function as a charge transport material, it is preferably an organic residue containing a nitrogen atom, and from the viewpoint of electrical properties, it preferably has a triarylamine skeleton. X is preferably an organic residue having two or more nitrogen atoms, more preferably an organic residue having a diphenylbenzidine skeleton, and further having a tetraphenylbenzidine skeleton. From the viewpoint of total balance such as charge mobility and stability.

In one embodiment of the present invention, the compounds represented by the general formula (1) and the general formula (2) are contained in the photosensitive layer at a content ratio that satisfies the formula represented by the following formula (A).
80> (mass of compound represented by general formula (1) / mass of compound represented by general formula (2))> 0 (A)

  By containing the two compounds in such a ratio in the photosensitive layer, the electrophotographic photosensitive member can have both a low residual potential and light resistance. The value of (mass of compound represented by general formula (1) / mass of compound represented by general formula (2)) is preferably 60 or less, more preferably 50 or less, considering mobility. More preferably, it is 40 or less. Considering the total balance, 30 or less is most preferable. The lower limit is preferably 1 or more in consideration of compatibility, more preferably 2 or more, and preferably 3 or more in consideration of total electrical characteristics and light fatigue characteristics, and more preferably 5 In view of ozone resistance, it is preferably 7 or more, and more preferably 9 or more.

  Further, instead of the mass content ratio represented by the above formula (A), the general formula (1) in the photosensitive layer can be obtained by using the measured value by high performance liquid chromatography (hereinafter also referred to as HPLC) or mass spectrum as it is. ) And an appropriate content ratio of the compound represented by the general formula (2) can also be determined.

  In the case of using the measured value by HPLC, in the present invention, the compounds represented by the general formula (1) and the general formula (2) are contained in the photosensitive layer at a content ratio satisfying the formula represented by the following formula (B). The

  80> (peak area of the compound represented by the general formula (1) in high performance liquid chromatography measurement (detection light wavelength 254 nm) / the compound represented by the general formula (2) in high performance liquid chromatography measurement (detection light wavelength 254 nm) Peak area)> 0 (B)

In the present invention, “the peak area of the compound represented by the general formula (1) (or the general formula (2)) in the high performance liquid chromatography measurement (detection light wavelength 254 nm)” means that the composition is dissolved in acetonitrile. A sample prepared by measuring a 0.3% by mass solution is a measurement sample, and the value measured under the following conditions. Usually, the measurement is performed three times and the average value is used.
UV detector: GL Sciences UV702
Pump: PU610 manufactured by GL Sciences
Mobile phase: acetonitrile (for HPLC)
Stationary phase: Inertsil (registered trademark) ODS-3V 150 mm manufactured by GL Sciences Inc.
Flow rate: 1 mL / min
Column temperature: 40 ° C

In the present invention, when the measurement value by mass spectrum is used, the compound represented by the general formula (1) and the general formula (2) has a content ratio satisfying the formula represented by the following formula (C). Contained in
80> (Molecular ion peak intensity of compound represented by general formula (1) in mass spectrum measurement / Molecular ion peak intensity of compound represented by general formula (2) in mass spectrum measurement)> 0 (C)

In the present invention, “the molecular ion peak intensity of the compound represented by the general formula (1) (or general formula (2)) in the mass spectrum measurement” refers to a 10 ppm solution obtained by dissolving the composition in chloroform. Is used as a measurement sample, 1 μL of the measurement sample is applied to a filament of a DCI probe, and mass spectrum measurement is performed under the following conditions. In the obtained mass spectrum, the compound represented by the general formula (1) or the general formula ( It is the peak intensity obtained from ion chromatography at the m / z value corresponding to the molecular ion of the compound represented by 2). Usually, measurement is repeated 5 times, and the average value is used.
Measuring device: JMS-700 manufactured by JEOL
Ionization mode: DCI (-)
Reaction gas: isobutane (ionization chamber pressure 1 × 10 ⁻⁵ Torr)
Temperature rising condition: 0 to 0.90 A (1 A / min)
Acceleration voltage: 8.0KV
Mass spectrometry: 2000
Scanning method: MF-Linear
Scan mass range: 500-1200
Total mass range scan time: 1.5 seconds

  In the formula (B), the peak area of the compound represented by the general formula (1) in (high performance liquid chromatography measurement (detection light wavelength 254 nm) / the general formula (2) in the high performance liquid chromatography measurement (detection light wavelength 254 nm) Peak area of the compound shown), and in the formula (C), the molecular ion peak intensity of the compound shown by the general formula (1) in the mass spectrum measurement / the compound shown by the general formula (2) in the mass spectrum measurement A preferable value of (molecular ion peak intensity) is the same as the value of (mass of compound represented by general formula (1) / mass of compound represented by general formula (2)) in formula (A). That is, when considering the mobility, it is preferably 60 or less, more preferably 50 or less, and still more preferably 40 or less. Considering the total balance, 30 or less is most preferable. The lower limit is preferably 1 or more in consideration of compatibility, more preferably 2 or more, and preferably 3 or more in consideration of total electrical characteristics and light fatigue characteristics, and more preferably 5 In view of ozone resistance, it is preferably 7 or more, and more preferably 9 or more.

  It is preferable that the compound represented by the general formula (1) and the compound represented by the general formula (2) are not produced separately but produced together at the time of production. Although various methods can be considered as a manufacturing method of these compounds, the method shown by the following scheme (I) is preferable, for example.

First, X which is a basic skeleton is formylated. As the method of formylation, electrophilic reaction is preferable, and synthesis can be performed by Vilsmeier reaction using phosphorus oxychloride and DMF. At this time, a Lewis acid such as ZnCl ₂ or AlCl ₃ may be used in combination.

  Here, by devising the reaction system, a mixture of aldehyde substitution products (m = 2, 3, etc.) can be obtained. When the formylation is carried out by the Vilsmeier reaction, it is preferable to use the number of moles of phosphorus oxychloride which is 1.5 times or more, more preferably 2 times or more the number of moles of the reaction site. The reaction temperature is preferably 60 ° C. or higher, more preferably 65 ° C. or higher, still more preferably 70 ° C. or higher, and particularly preferably 75 ° C. or higher.

  The formyl body mixture obtained here is provided with a double bond by a known method such as a wittig reaction, and is made into a composition containing the compounds represented by the general formulas (1) and (2). That is, the target composition can be obtained without separately preparing a bisformyl body and a triformyl body.

  Specific examples (1-a) to (1-u) and (2-a) to (2-u) of the structures of the compounds represented by the general formulas (1) and (2) are illustrated below. These are for detailed description of the present invention, and are not limited to the following structure unless contrary to the gist of the present invention. In addition, compound (1-a)-(1-u) is an illustration about the compound shown by General formula (1), and compound (2-a)-(2-u) is shown by General formula (2). It is an illustration about the compound.

  The electrophotographic photosensitive member of the present invention is not particularly limited as long as the photosensitive layer containing the compounds represented by the general formula (1) and the general formula (2) is provided on the conductive support. . Hereinafter, specific examples of the electrophotographic photosensitive member according to the present invention, an image forming apparatus using the same, and an electrophotographic photosensitive member cartridge will be described in detail.

1. Electrophotographic photoreceptor <Conductive support>
There are no particular restrictions on the conductive support, but for example, metal materials such as aluminum, aluminum alloy, stainless steel, copper, and nickel, and conductive powders such as metal, carbon, and tin oxide are added to impart conductivity. A resin material, a resin, glass, paper, or the like on which a conductive material such as aluminum, nickel, or ITO (indium tin oxide) is deposited or applied on the surface is mainly used. These may be used individually by 1 type and may use 2 or more types together by arbitrary combinations and ratios. As a form of the conductive support, a drum form, a sheet form, a belt form or the like is used. Furthermore, a conductive material having an appropriate resistance value may be used on a conductive support made of a metal material in order to control conductivity and surface properties and to cover defects.

  Moreover, when using metal materials, such as an aluminum alloy, as an electroconductive support body, you may use, after giving an anodic oxide film. When an anodized film is applied, it is desirable to perform a sealing treatment by a known method.

  The support surface may be smooth, or may be roughened by using a special cutting method or performing a polishing treatment. Further, it may be roughened by mixing particles having an appropriate particle diameter with the material constituting the support. In order to reduce the cost, it is possible to use the drawing tube as it is without performing the cutting process.

<Underlayer>
An undercoat layer may be provided between the conductive support and the photosensitive layer described later for improving adhesion and blocking properties. As the undercoat layer, a resin, a resin in which particles such as a metal oxide are dispersed, or the like is used. Further, the undercoat layer may be a single layer or a plurality of layers.

  Examples of the metal oxide particles used for the undercoat layer include metal oxide particles containing one metal element such as titanium oxide, aluminum oxide, silicon oxide, zirconium oxide, zinc oxide, and iron oxide, calcium titanate, and titanium. Examples thereof include metal oxide particles containing a plurality of metal elements such as strontium acid and barium titanate. One kind of these particles may be used alone, or a plurality of kinds of particles may be mixed and used in an arbitrary combination and ratio. Among these metal oxide particles, titanium oxide and aluminum oxide are preferable, and titanium oxide is particularly preferable. The surface of the titanium oxide particles may be treated with an inorganic substance such as tin oxide, aluminum oxide, antimony oxide, zirconium oxide or silicon oxide, or an organic substance such as stearic acid, polyol or silicone. As the crystal form of the titanium oxide particles, any of rutile, anatase, brookite, and amorphous can be used. The titanium oxide particles may have only one crystal type, or may contain two or more crystal types in any combination and ratio.

  Various particle diameters of the metal oxide particles can be used. In particular, from the viewpoint of the characteristics of the binder resin, etc., which is the raw material of the undercoat layer, and the stability of the liquid, any 10 observed by the SEM photograph. The average value of the maximum diameter of the individual particles is defined as the average primary particle size, and the average primary particle size is usually 10 nm or more, and usually 100 nm or less, preferably 50 nm or less.

The undercoat layer is preferably formed in a form in which metal oxide particles are dispersed in a binder resin.
The binder resin used for the undercoat layer is epoxy resin, polyethylene resin, polypropylene resin, acrylic resin, methacrylic resin, polyamide resin, vinyl chloride resin, vinyl acetate resin, phenol resin, polycarbonate resin, polyurethane resin, polyimide resin, chloride resin. Vinylidene resin, polyvinyl acetal resin, vinyl chloride-vinyl acetate copolymer, polyvinyl alcohol resin, polyurethane resin, polyacrylic acid resin, polyacrylamide resin, polyvinyl pyrrolidone resin, polyvinyl pyridine resin, water-soluble polyester resin, cellulose such as nitrocellulose Ester resin, cellulose ether resin, casein, gelatin, polyglutamic acid, starch, starch acetate, amino starch, zirconium chelate compound, zirconi Organic zirconium compounds of the arm alkoxide compounds, titanyl chelate compounds, organic titanyl compounds such as titanyl alkoxide compound, a known binder resin such as a silane coupling agent and the like. These may be used alone or in combination of two or more in any combination and ratio. Moreover, you may use with the hardening | curing form with the hardening | curing agent. Of these, alcohol-soluble copolymerized polyamides, modified polyamides, and the like are preferable because they exhibit good dispersibility and coatability.

  The use ratio of the metal oxide particles to the binder resin used in the undercoat layer can be arbitrarily selected, but from the viewpoint of the stability of the coating liquid and coating properties, it is usually based on 100 parts by mass of the binder resin. It is preferable to use in the range of 10 to 500 parts by mass.

  The thickness of the undercoat layer can also be arbitrarily selected. However, from the viewpoint of improving the electrical characteristics, strong exposure characteristics, image characteristics, repeat characteristics, and coating properties during production of the electrophotographic photosensitive member, it is usually 0. It is desired to be 01 μm or more, preferably 0.1 μm or more, and usually 50 μm or less, preferably 30 μm or less.

  The undercoat layer may be mixed with a known antioxidant or the like, and may contain pigment particles, resin particles, etc. for the purpose of preventing image defects.

<Photosensitive layer>
The photosensitive layer is formed on the above-mentioned conductive support (or on the undercoat layer when the above-described undercoat layer is provided). As the type of the photosensitive layer of the electrophotographic photosensitive member, a charge generation material and a charge transport material are present in the same layer and have a single layer structure dispersed in a binder resin (hereinafter referred to as “single layer type photosensitive layer” as appropriate). Including a charge generation layer in which a charge generation material is dispersed in a binder resin and a charge transport layer in which a charge transport material is dispersed in a binder resin. As appropriate, it may be referred to as “laminated photosensitive layer”), but any type can be used in the present invention.

  In addition, as the laminated photosensitive layer, a charge generation layer and a charge transport layer are laminated in this order from the conductive support side, and a charge transport layer and a charge generation layer are laminated in this order. Although there is a reverse laminated type photosensitive layer, any of them can be adopted.

  As the photosensitive layer in the present invention, a laminate type photosensitive layer in which a charge generation layer and a charge transport layer are laminated is preferable. In particular, the charge transport layer is a compound represented by general formula (1) or general formula (2). It is preferable to contain. Further, among the laminated type photosensitive layers, a forward laminated type photosensitive layer capable of exhibiting balanced photoconductivity is particularly preferable.

(Laminated photosensitive layer)
-Charge generation layer The charge generation layer of the multilayer photosensitive layer contains a charge generation material and usually contains a binder resin and other components used as necessary. Such a charge generation layer is prepared by, for example, preparing a coating solution by dissolving or dispersing a charge generation material and a binder resin in a solvent or a dispersion medium. (If an undercoat layer is provided, it can be obtained on the undercoat layer). In the case of a reverse laminated type photosensitive layer, it can be obtained by coating on a charge transport layer and drying.

  Examples of the charge generation material include inorganic photoconductive materials such as selenium and its alloys, cadmium sulfide, and organic photoconductive materials such as organic pigments, but organic photoconductive materials are preferred, especially organic pigments. Is preferred. Examples of organic pigments include phthalocyanine pigments, azo pigments, dithioketopyrrolopyrrole pigments, squalene (squarylium) pigments, quinacridone pigments, indigo pigments, perylene pigments, polycyclic quinone pigments, anthanthrone pigments, and benzimidazole pigments. . Among these, phthalocyanine pigments or azo pigments are particularly preferable in that they have high sensitivity in a wide range of wavelengths from 500 nm to 900 nm.

  When using a phthalocyanine pigment as a charge generation material, specifically, metal-free phthalocyanine, copper, indium, gallium, tin, titanium, zinc, vanadium, silicon, germanium, aluminum or other metal or oxide thereof, halide, water Various crystal forms of coordinated phthalocyanines such as oxides and alkoxides are used. In particular, titanyl phthalocyanines (also known as oxytitanium) such as X-type, τ-type metal-free phthalocyanine, A-type (also known as β-type), B-type (also known as α-type), and D-type (also known as Y-type), which are highly sensitive crystal types Phthalocyanine), vanadyl phthalocyanine, chloroindium phthalocyanine, chlorogallium phthalocyanine such as type II, hydroxygallium phthalocyanine such as type V, μ-oxo-gallium phthalocyanine dimer such as type G and I, μ-oxo such as type II -Aluminum phthalocyanine dimer is preferred.

  Further, among phthalocyanines, oxytitanium phthalocyanine having a main diffraction peak at a Bragg angle (2θ ± 0.2 °) of X-ray diffraction spectrum with respect to CuKa characteristic X-ray of 27.3 ° is 9.3 °, 10. Oxytitanium phthalocyanine showing main diffraction peaks at 6 ° and 26.3 °, dihydroxysilicon phthalocyanine having main diffraction peaks at 9.2 °, 14.1 °, 15.3 °, 19.7 °, 27.1 ° 8.5 °, 12.2 °, 13.8 °, 16.9 °, 22.4 °, 28.4 °, dichlorotin phthalocyanine showing the main diffraction peaks at 30.1 °, 7.5 °, Hydroxy potassium phthalocyanine showing main diffraction peaks at 9.9 °, 12.5 °, 16.3 °, 18.6 °, 25.1 ° and 28.3 °, and 7.4 °, 16 6 °, chlorogallium phthalocyanine preferably exhibits a diffraction peak at 25.5 ° and 28.3 °. Among these, oxytitanium phthalocyanine having a main diffraction peak at 27.3 ° is particularly preferable, and in this case, oxytitanium phthalocyanine having main diffraction peaks at 9.5 °, 24.1 °, and 27.3 ° is particularly preferable. . The Bragg angle has an error of ± 0.2 ° as indicated by 2θ ± 0.2 °. Therefore, for example, “Bragg angle (2θ ± 0.2 °) 27.3 °” means a range of 27.1 ° to 27.5 °. This error range is the same at other angles.

  Furthermore, from the viewpoint of electrical characteristics of the electrophotographic photosensitive member, it is preferable to use phthalocyanine having a total chlorine content (element) content of 0.6% by mass or less. Usually, the amount of chlorine content of phthalocyanine can be measured by elemental analysis of crystals (powder) of the phthalocyanine compound.

  As the phthalocyanine compound, any one kind of compound may be used alone, or a mixed or mixed crystal state of plural kinds of compounds may be used. As the mixed state in the phthalocyanine compound or crystal state here, those obtained by mixing the respective constituent elements later may be used, or the mixed state in the production / treatment process of the phthalocyanine compound such as synthesis, pigmentation, crystallization, etc. It may be the one that gave rise to. As such treatment, acid paste treatment, grinding treatment, solvent treatment and the like are known. In order to generate a mixed crystal state, as described in JP-A-10-48859, two types of crystals are mixed, mechanically ground and made amorphous, and then converted into a specific crystal state by solvent treatment. The method of doing is mentioned.

  When an azo pigment is used as the charge generation material, various bisazo pigments and trisazo pigments are preferably used. Examples of preferred azo pigments are shown below.

  When the organic pigment exemplified above is used as the charge generation material, one kind may be used alone, or two or more kinds of pigments may be mixed and used. In this case, it is preferable to use a combination of two or more kinds of charge generating materials having spectral sensitivity characteristics in different spectral regions of the visible region and the near red region, and in particular, use a combination of a disazo pigment or a trisazo pigment and a phthalocyanine pigment. Is more preferable.

  The charge generation layer may be formed as a vapor deposition film or the like using the above-described charge generation material alone, but is usually used in a form in which the charge generation material is bound with a binder resin. In particular, when organic pigments are used as the charge generating material, it is preferable to use these organic pigment particles in a form bound with a binder resin. There is no restriction | limiting in binder resin to be used, Arbitrary resin can be used. Specific examples thereof include polyvinyl butyral resin, polyvinyl formal resin, polyvinyl acetal resins such as partially acetalized polyvinyl butyral resin in which a part of butyral is modified with formal or acetal, polyarylate resin, polycarbonate resin, polyester resin , Modified ether polyester resin, phenoxy resin, polyvinyl chloride resin, polyvinylidene chloride resin, polyvinyl acetate resin, polystyrene resin, acrylic resin, methacrylic resin, polyacrylamide resin, polyamide resin, polyvinyl pyridine resin, cellulose resin, polyurethane Resin, epoxy resin, silicone resin, polyvinyl alcohol resin, polyvinylpyrrolidone resin, casein, vinyl chloride-vinyl acetate copolymer, hydroxy-modified vinyl chloride Ru-vinyl acetate copolymer, carboxyl-modified vinyl chloride-vinyl acetate copolymer, vinyl chloride-vinyl acetate copolymer such as vinyl chloride-vinyl acetate-maleic anhydride copolymer, styrene-butadiene copolymer, Insulating resin such as vinylidene chloride-acrylonitrile copolymer, styrene-alkyd resin, silicone-alkyd resin, phenol-formaldehyde resin, organic photoconductive polymer such as poly-N-vinylcarbazole, polyvinylanthracene, polyvinylperylene, etc. Can be mentioned. In addition, for example, polymers of vinyl compounds such as polyvinyl acetate, polyvinyl acetoacetal, polyvinyl propional, cellulose ester, cellulose ether, styrene, vinyl acetate, vinyl chloride, acrylic ester, methacrylic ester, vinyl alcohol, ethyl vinyl ether, etc. And copolymers, polyamides, silicon resins and the like. In addition, these may be used individually by 1 type and may use 2 or more types together by arbitrary combinations and ratios.

  In the charge generation layer, the mixing ratio (mass) of the binder resin and the charge generation material is usually 1 part by mass or more, preferably 10 parts by mass or more, more preferably 30 parts by mass with respect to 100 parts by mass of the binder resin. It is usually 2000 parts by mass or less, preferably 1000 parts by mass or less, more preferably 500 parts by mass or less. If the ratio of the charge generation material is too high, the stability of the coating solution may be reduced due to aggregation of the charge generation material, while if the ratio of the charge generation material is too low, the sensitivity as a photoreceptor may be decreased. There is.

  The film thickness of the charge generation layer is usually 0.05 μm or more, preferably 0.1 μm or more, more preferably 0.15 μm or more, and usually 10 μm or less, preferably 5 μm or less, more preferably 2 μm or less, even more preferably. Is in the range of 0.8 μm or less.

  As a method for dispersing the charge generation material in the dispersion medium, a known dispersion method such as a ball mill dispersion method, an attritor dispersion method, a sand mill dispersion method, a planetary mill dispersion method, a roll mill dispersion method, or an ultrasonic dispersion method is arbitrarily used. be able to. When dispersing, it is effective to reduce the particle size of the charge generating substance to a particle size of usually 1 μm or less, preferably 0.5 μm or less, more preferably 0.3 μm or less, and even more preferably 0.15 μm or less.

-Charge transport layer The charge transport layer of the multilayer photoconductor contains a charge transport material and usually contains a binder resin and other components used as necessary. Specifically, such a charge transport layer is prepared by, for example, preparing a coating solution by dissolving or dispersing a charge transport material and a binder resin in a solvent or a dispersion medium. It can be obtained by coating and drying on a charge generation layer, or in the case of a reverse lamination type photosensitive layer, on a conductive support (or on an undercoat layer when an undercoat layer is provided).

  In the present invention, the compounds represented by the general formulas (1) and (2) described above are used as the charge transport material. One of these compounds may be used alone, or a plurality of these compounds may be used in any combination and ratio. Furthermore, in addition to the compounds represented by the general formulas (1) and (2), other known charge transport materials may be used in combination.

  Further, in the present invention, the compounds represented by the general formulas (1) and (2) contained in the photosensitive layer, that is, the compound substituted with X (having a double bond) has two compounds and three Although the ratio of the compounds is specified, as shown in the following general formulas (3) and (4), one substituent and four compounds may be simultaneously contained in the substituent for X. .

In general formulas (3) and (4), R ^{1 to} R ⁵ , X, and n are as defined in general formulas (1) and (2).

  When the compounds represented by the general formulas (1) and (2) are used in combination with other charge transport materials, the ratio is not particularly limited, but the compounds represented by the general formulas (1) and (2) and other compounds The mass ratio of the compounds represented by the general formulas (1) and (2) to the total amount of the charge transport material is preferably 50% by mass or more.

  When other charge transport materials are used in combination, the type is not particularly limited, but examples include aromatic nitro compounds such as 2,4,7-trinitrofluorenone, cyano compounds such as tetracyanoquinodimethane, diphenoquinone, etc. Electron withdrawing substances such as quinone compounds, carbazole derivatives, indole derivatives, imidazole derivatives, oxazole derivatives, pyrazole derivatives, thiadiazole derivatives, heterocyclic compounds such as benzofuran derivatives, aniline derivatives, hydrazone derivatives, aromatic amine derivatives, stilbene derivatives, Examples thereof include butadiene derivatives, enamine derivatives and those obtained by bonding a plurality of these compounds, or electron donating substances such as polymers having a group consisting of these compounds in the main chain or side chain. Among these, carbazole derivatives, aromatic amine derivatives, stilbene derivatives, butadiene derivatives, enamine derivatives, and those in which a plurality of these compounds are bonded are preferable. Any one of these other charge transport materials may be used alone, or two or more may be used in any combination.

  The binder resin used for the charge transporting layer is not limited in type, and any known resin can be used arbitrarily. For example, butadiene resin, styrene resin, vinyl acetate resin, vinyl chloride resin, acrylic ester resin Polymers and copolymers of vinyl compounds such as methacrylic acid ester resins, vinyl alcohol resins, polyvinyl butyral resins, polyvinyl formal resins, partially modified polyvinyl acetal resins, polyethyl vinyl ether resins, polymethyl methacrylate resins, polycarbonate resins, polyester resins , Polyester carbonate resin, polyarylate resin, polysulfone resin, polyamide resin, polyimide resin, polyurethane resin, cellulose ester resin, phenoxy resin, silicone resin, silicone-alkoxy De resins, poly -N- vinylcarbazole resins, and epoxy resins. These can also be used by crosslinking with an appropriate curing agent by heat, light or the like. Moreover, these may be used individually by 1 type and may use 2 or more types together by arbitrary combinations and a ratio.

  In the photosensitive layer of the present invention, particularly preferably used binder resins include polycarbonate resins and polyester resins. Polycarbonate resins and polyester resins generally have a partial structure of a diol component. Examples of the diol component forming these structures include bisphenol residues and biphenol residues. Specific examples thereof include bis- (4-hydroxy-3,5-dimethylphenyl) methane, bis- (4- Hydroxyphenyl) methane, bis- (4-hydroxy-3-methylphenyl) methane, 1,1-bis- (4-hydroxyphenyl) ethane, 1,1-bis- (4-hydroxyphenyl) propane, 2,2 -Bis- (4-hydroxyphenyl) propane, 2,2-bis- (4-hydroxy-3-methylphenyl) propane, 2,2-bis- (4-hydroxyphenyl) butane, 2,2-bis- ( 4-hydroxyphenyl) pentane, 2,2-bis- (4-hydroxyphenyl) -3-methylbutane, 2,2-bis- (4-hydroxyphenyl) Nyl) hexane, 2,2-bis- (4-hydroxyphenyl) -4-methylpentane, 1,1-bis- (4-hydroxyphenyl) cyclopentane, 1,1-bis- (4-hydroxyphenyl) cyclohexane Bis- (3-phenyl-4-hydroxyphenyl) methane, 1,1-bis- (3-phenyl-4-hydroxyphenyl) ethane, 1,1-bis- (3-phenyl-4-hydroxyphenyl) propane 2,2-bis- (3-phenyl-4-hydroxyphenyl) propane, 1,1-bis- (4-hydroxy-3-methylphenyl) ethane, 2,2-bis- (4-hydroxy-3- Methylphenyl) propane, 2,2-bis- (4-hydroxy-3-ethylphenyl) propane, 2,2-bis- (4-hydroxy-3-isopropyl) Phenyl) propane, 2,2-bis- (4-hydroxy-3-sec-butylphenyl) propane, 1,1-bis- (4-hydroxy-3,5-dimethylphenyl) ethane, 2,2-bis- (4-hydroxy-3,5-dimethylphenyl) propane, 1,1-bis (4-hydroxy-3,5-dimethylphenyl) cyclohexane, 1,1-bis- (4-hydroxy-3,6-dimethylphenyl) ) Ethane, bis- (4-hydroxy-2,3,5-trimethylphenyl) methane, 1,1-bis- (4-hydroxy-2,3,5-trimethylphenyl) ethane, 2,2-bis- ( 4-hydroxy-2,3,5-trimethylphenyl) propane, bis- (4-hydroxy-2,3,5-trimethylphenyl) phenylmethane, 1,1-bis- (4-H Droxy-2,3,5-trimethylphenyl) phenylethane, 1,1-bis- (4-hydroxy-2,3,5-trimethylphenyl) cyclohexane, bis- (4-hydroxyphenyl) phenylmethane, 1,1 -Bis- (4-hydroxyphenyl) -1-phenylethane, 1,1-bis- (4-hydroxyphenyl) -1-phenylpropane, bis- (4-hydroxyphenyl) diphenylmethane, bis- (4-hydroxyphenyl) ) Dibenzylmethane, 4,4 ′-[1,4-phenylenebis (1-methylethylidene)] bis- [phenol], 4,4 ′-[1,4-phenylenebismethylene] bis- [phenol], 4,4 ′-[1,4-phenylenebis (1-methylethylidene)] bis- [2,6-dimethylphenol], 4,4 ′ [1,4-phenylenebismethylene] bis- [2,6-dimethylphenol], 4,4 ′-[1,4-phenylenebismethylene] bis- [2,3,6-trimethylphenol], 4,4 '-[1,4-phenylenebis (1-methylethylidene)] bis- [2,3,6-trimethylphenol], 4,4'-[1,3-phenylenebis (1-methylethylidene)] bis- [2,3,6-trimethylphenol], 4,4′-dihydroxydiphenyl ether, 4,4-bis (4-hydroxyphenyl) valeric acid stearyl ester, 4,4′-dihydroxydiphenylsulfone, 4,4′-dihydroxy Diphenyl sulfide, 3,3 ′, 5,5′-tetramethyl-4,4′-dihydroxydiphenyl ether, 3,3 ′, 5,5′-tetramethyl 4,4′-dihydroxydiphenylsulfone, 3,3 ′, 5,5′-tetramethyl-4,4′-dihydroxydiphenyl sulfide, phenolphthalein, 4,4 ′-[1,4-phenylenebis ( 1-methylvinylidene)] bisphenol, 4,4 ′-[1,4-phenylenebis (1-methylvinylidene)] bis [2-methylphenol], (2-hydroxyphenyl) (4-hydroxyphenyl) methane, 2-hydroxy-5-methylphenyl) (4-hydroxy-3-methylphenyl) methane, 1,1- (2-hydroxyphenyl) (4-hydroxyphenyl) ethane, 2,2- (2-hydroxyphenyl) ( 4-hydroxyphenyl) propane, 1,1- (2-hydroxyphenyl) (4-hydroxyphenyl) propane, Bisphenol components such as 4,4′-biphenol, 2,4′-biphenol, 3,3′-dimethyl-4,4′-dihydroxy-1,1′-biphenyl, 3,3′-dimethyl-2,4 '-Dihydroxy-1,1'-biphenyl, 3,3'-di- (t-butyl) -4,4'-dihydroxy-1,1'-biphenyl, 3,3', 5,5'-tetramethyl -4,4'-dihydroxy-1,1'-biphenyl, 3,3 ', 5,5'-tetra- (t-butyl) -4,4'-dihydroxy-1,1'-biphenyl, 2,2 Examples include biphenol components such as ', 3,3', 5,5'-hexamethyl-4,4'-dihydroxy-1,1'-biphenyl.

  Among these, preferred compounds include bis- (4-hydroxy-3,5-dimethylphenyl) methane, bis- (4-hydroxyphenyl) methane, bis- (4-hydroxy-3-methylphenyl) methane, 2 , 2-bis- (4-hydroxy-3-methylphenyl) propane, 1,1-bis- (4-hydroxyphenyl) ethane, 2,2-bis- (4-hydroxyphenyl) propane, 2-hydroxyphenyl ( Bisphenol components such as 4-hydroxyphenyl) methane and 2,2- (2-hydroxyphenyl) (4-hydroxyphenyl) propane may be mentioned.

  Below, the diol component (bisphenol, biphenol, etc.) of the polycarbonate resin which can be used conveniently is illustrated.

  In particular, in order to maximize the effects of the present invention, a diol component having the following structure is preferable.

  In order to improve mechanical properties, it is preferable to use polyarylate. In this case, it is preferable to use the following structure as the diol component,

酸成分としては、以下構造を用いることが好ましい。

As the acid component, the following structure is preferably used.

  Particularly preferred acid components are as follows.

また、これらのジカルボン酸成分、ジオール成分を複数種組み合わせて用いることも可能である。

Moreover, it is also possible to use these dicarboxylic acid components and diol components in combination.

  If the molecular weight of the binder resin is too low, the mechanical strength is insufficient. On the other hand, if the molecular weight is too high, the viscosity of the coating solution for forming the photosensitive layer is too high, resulting in a decrease in productivity. In the case of a polyarylate resin, the viscosity average molecular weight is 10,000 or more, preferably 20,000 or more, and 100,000 or less, more preferably 70,000 or less.

  The ratio of the binder resin and the charge transport material is arbitrary, but the charge transport material is usually mixed at a ratio of 20 parts by mass or more with respect to 100 parts by mass of the binder resin. Among these, 30 parts by mass or more is preferable from the viewpoint of reducing the residual potential, and 40 parts by mass or more is more preferable from the viewpoint of stability and charge mobility when repeatedly used. On the other hand, from the viewpoint of thermal stability of the photosensitive layer, the charge transport material is usually used at a ratio of 150 parts by mass or less. Among these, 120 parts by mass or less is preferable from the viewpoint of compatibility between the charge transport material and the binder resin, 100 parts by mass or less is more preferable from the viewpoint of printing durability, and 80 parts by mass or less is particularly preferable from the viewpoint of scratch resistance. When a plurality of types of charge transport materials are used in combination, the total of these charge transport materials is set within the above range.

  Further, the charge transport layer may contain an electron withdrawing compound. As the electron-withdrawing compound, any compound can be used as long as the effects of the present invention are not significantly impaired. For example, chloranil, 2,3-dichloro-1,4-naphthoquinone, 1-nitroanthraquinone, 1-chloro Quinones such as -5-nitroanthraquinone, 2-chloroanthraquinone, phenanthrenequinone; aldehydes such as 4-nitrobenzaldehyde; 9-benzoylanthracene, indandione, 3,5-dinitrobenzophenone, 2,4,7-trinitro Ketones such as fluorenone, 2,4,5,7-tetranitrofluorenone, 3,3 ′, 5,5′-tetranitrobenzophenone; acid anhydrides such as phthalic anhydride and 4-chloronaphthalic anhydride; tetracyano Ethylene, terephthalalmalononitrile, 9-anthrylmethylidenemalo Cyano compounds such as nitrile, 4-nitrobenzalmalononitrile, 4- (p-nitrobenzoyloxy) benzalmalononitrile; 3-benzalphthalide, 3- (α-cyano-p-nitrobenzal) phthalide, 3- (α- And phthalides such as cyano-p-nitrobenzal) -4,5,6,7-tetrachlorophthalide. In addition, these may be used individually by 1 type and may use 2 or more types together by arbitrary combinations and ratios.

  The thickness of the charge transport layer is not particularly limited, but is usually 5 μm or more, preferably 10 μm or more, and usually 50 μm or less, preferably 45 μm or less, from the viewpoint of long life, image stability, and high resolution. Is in the range of 30 μm or less.

(Single layer type photosensitive layer)
The single-layer type photosensitive layer is formed using a binder resin in order to ensure film strength, in the same manner as the charge transport layer of the multilayer photoconductor, in addition to the charge generation material and the charge transport material. Specifically, a charge generation material, a charge transport material, and various binder resins are dissolved or dispersed in a solvent to prepare a coating solution, and on a conductive support (or an undercoat layer when an undercoat layer is provided). It can be obtained by coating and drying.

  The types of the charge transport material and the binder resin, and the use ratios thereof are the same as those described for the charge transport layer of the multilayer photoreceptor. In the single-layer type photosensitive layer, a charge generating material is further dispersed in a charge transport medium comprising these charge transport material and binder resin.

  As the charge generation material, the same materials as those described for the charge generation layer of the multilayer photoreceptor can be used. However, in the case of a photosensitive layer of a single-layer type photoreceptor, it is necessary to sufficiently reduce the particle size of the charge generating material. Specifically, the range is usually 1 μm or less, preferably 0.5 μm or less.

  If the amount of the charge generating material dispersed in the single-layer type photosensitive layer is too small, sufficient sensitivity cannot be obtained, but if it is too large, there are adverse effects such as a decrease in chargeability and a decrease in sensitivity. It is used in the range of usually 0.5% by mass or more, preferably 1% by mass or more, and usually 50% by mass or less, preferably 20% by mass or less based on the whole layer-type photosensitive layer.

  In addition, the usage ratio of the binder resin and the charge generation material in the single-layer type photosensitive layer is such that the charge generation material is usually 0.1 parts by mass or more, preferably 1 part by mass or more, and usually 100 parts by mass of the binder resin It is 30 mass parts or less, Preferably it is set as the range of 10 mass parts or less.

  The film thickness of the single-layer type photosensitive layer is usually 5 μm or more, preferably 10 μm or more, and usually 100 μm or less, preferably 50 μm or less.

  In addition, in both the multilayer type photoreceptor and the single layer type photoreceptor, the film forming property, flexibility, coating property, stain resistance, gas resistance, light resistance, etc. are improved for the photosensitive layer or each layer constituting the photosensitive layer. For the purpose, additives such as known antioxidants, plasticizers, ultraviolet absorbers, electron-withdrawing compounds, leveling agents, and visible light shielding agents may be contained.

  Examples of additives used in the charge transport layer include plasticizers and crosslinking agents, antioxidants, stabilizers, sensitizers used to improve film formability, flexibility, and mechanical strength. Examples of the additives include various leveling agents and dispersion aids for improving the coating property. Examples of the plasticizer include phthalic acid esters, phosphoric acid esters, epoxy compounds, chlorinated paraffins, chlorinated fatty acid esters, and aromatic compounds such as methyl naphthalene. Leveling agents include, for example, silicone oil and fluorine-based oil. Etc.

(Other functional layers)
In both the multilayer type photoreceptor and the single-layer type photoreceptor, the photosensitive layer formed by the above procedure may be the uppermost layer, that is, the surface layer, but another layer may be provided on the photosensitive layer, and this may be used as the surface layer. For example, a protective layer may be provided for the purpose of preventing wear of the photosensitive layer or preventing or reducing deterioration of the photosensitive layer due to discharge products generated from a charger or the like.

  The protective layer is formed by containing a conductive material in a suitable binder resin, or a copolymer using a compound having charge transporting ability such as a triphenylamine skeleton described in JP-A-9-190004. Can be used.

  Examples of the conductive material used for the protective layer include aromatic amino compounds such as TPD (N, N′-diphenyl-N, N′-bis- (m-tolyl) benzidine), antimony oxide, indium oxide, tin oxide, and oxide. Metal oxides such as titanium, tin oxide-antimony oxide, aluminum oxide, and zinc oxide can be used, but are not limited thereto.

  As the binder resin used for the protective layer, known resins such as polyamide resin, polyurethane resin, polyester resin, epoxy resin, polyketone resin, polycarbonate resin, polyvinyl ketone resin, polystyrene resin, polyacrylamide resin, and siloxane resin can be used. Also, a copolymer of the above resin with a skeleton having a charge transporting ability such as a triphenylamine skeleton as described in JP-A-9-190004 can be used.

The electrical resistance of the protective layer is usually in the range of 10 ⁹ Ω · cm to 10 ¹⁴ Ω · cm. If the electric resistance is higher than the above range, the residual potential is increased, resulting in an image with much fog. On the other hand, if the electric resistance is lower than the above range, the image is blurred and the resolution is reduced. Further, the protective layer must be configured so as not to substantially prevent transmission of light irradiated during image exposure.

  Further, for the purpose of reducing the frictional resistance and wear on the surface of the photoconductor, and increasing the transfer efficiency of the toner from the photoconductor to the transfer belt and paper, etc., the surface layer is made of a fluororesin, silicone resin, polyethylene resin, or the like. Particles made of the above resin or inorganic compound particles may be contained in the surface layer. Alternatively, a layer containing these resins and particles may be newly formed as a surface layer.

<Method for forming electrophotographic photoreceptor>
Each of the above-described layers constituting the photoconductor is formed by laminating a coating solution obtained by dissolving or dispersing a substance to be contained in a solvent or a dispersion medium by sequentially repeating coating and drying steps using a known technique. It is formed.

  There is no particular limitation on the solvent or dispersion medium used for the preparation of the coating liquid, but considering the purpose of each layer and the properties of the selected solvent / dispersion medium, the physical properties such as solid content concentration and viscosity of the coating liquid are in the desired range. It is preferable to adjust as appropriate.

  For example, in the case of a single layer type photosensitive layer and a charge transport layer of a laminated type photosensitive layer, the solid content concentration of the coating solution is usually 5% by mass or more, preferably 10% by mass or more, and usually 40% by mass or less. Preferably it is set as the range of 35 mass% or less. Further, the viscosity of the coating solution is usually 10 mPa · s or higher, preferably 50 mPa · s or higher, and usually 500 mPa · s or lower, preferably 400 mPa · s or lower.

  In the case of the charge generation layer of the laminated photosensitive layer, the solid content concentration of the coating solution is usually 0.1% by mass or more, preferably 1% by mass or more, and usually 15% by mass or less, preferably 10% by mass. % Or less. Further, the viscosity of the coating solution is usually 0.01 mPa · s or more, preferably 0.1 mPa · s or more, and usually 20 mPa · s or less, preferably 10 mPa · s or less.

  Specific examples of the solvent or dispersion medium used for preparing the coating solution include alcohols such as methanol, ethanol, propanol and 2-methoxyethanol, ethers such as tetrahydrofuran, 1,4-dioxane and dimethoxyethane, methyl formate, Esters such as ethyl acetate, ketones such as acetone, methyl ethyl ketone, cyclohexanone, 4-methoxy-4-methyl-2-pentanone, aromatic hydrocarbons such as benzene, toluene, xylene, dichloromethane, chloroform, 1,2- Chlorinated hydrocarbons such as dichloroethane, 1,1,2-trichloroethane, 1,1,1-trichloroethane, tetrachloroethane, 1,2-dichloropropane, trichloroethylene, n-butylamine, isopropanolamine, diethylamine, triethanol Amine, ethylenediamine, nitrogen-containing compounds such as triethylenediamine, acetonitrile, N- methylpyrrolidone, N, N- dimethylformamide, aprotic polar solvents such as dimethyl sulfoxide and the like. Moreover, these may be used individually by 1 type and may use 2 or more types together by arbitrary combinations and kinds.

  Examples of the coating method include a dip coating method, a spray coating method, a spinner coating method, a bead coating method, a wire bar coating method, a blade coating method, a roller coating method, an air knife coating method, and a curtain coating method. Other known coating methods can also be used.

  The coating solution is preferably dried by touching at room temperature, followed by heating or drying in a temperature range of usually 30 ° C. or more and 200 ° C. or less for 1 minute to 2 hours, while still or blowing. Further, the heating temperature may be constant, or heating may be performed while changing the temperature during drying.

2. Image Forming Apparatus and Electrophotographic Photoreceptor Cartridge Next, an image forming apparatus using the electrophotographic photosensitive member of the present invention (image forming apparatus of the present invention) will be described with reference to FIG. I will explain. However, the embodiment is not limited to the following description, and can be arbitrarily modified without departing from the gist of the present invention.

  As shown in FIG. 1, the image forming apparatus includes an electrophotographic photosensitive member 1, a charging device 2, an exposure device 3, and a developing device 4, and further, a transfer device 5, a cleaning device 6 and a fixing device as necessary. A device 7 is provided.

  The electrophotographic photosensitive member 1 is not particularly limited as long as it is the above-described electrophotographic photosensitive member of the present invention, but in FIG. 1, as an example, a drum-like shape in which a photosensitive layer is formed on the surface of a cylindrical conductive support. The photoconductor is shown. A charging device 2, an exposure device 3, a developing device 4, a transfer device 5, and a cleaning device 6 are arranged along the outer peripheral surface of the electrophotographic photoreceptor 1.

  The charging device 2 charges the electrophotographic photosensitive member 1 and uniformly charges the surface of the electrophotographic photosensitive member 1 to a predetermined potential. Examples of the charging device include a corona charging device such as a corotron and a scorotron, a direct charging device (contact type charging device) that charges a direct charging member to which a voltage is applied by contacting the photosensitive member surface, and a contact type charging device such as a charging brush. Often used. Examples of direct charging means include contact chargers such as charging rollers and charging brushes. In FIG. 1, a roller-type charging device (charging roller) is shown as an example of the charging device 2. As the direct charging means, either charging with air discharge or injection charging without air discharge is possible. In addition, as a voltage applied at the time of charging, in the case of only a direct current voltage, an alternating current can be superimposed on a direct current.

  The type of the exposure apparatus 3 is not particularly limited as long as it can expose the electrophotographic photoreceptor 1 to form an electrostatic latent image on the photosensitive surface of the electrophotographic photoreceptor 1. Specific examples include halogen lamps, fluorescent lamps, lasers such as semiconductor lasers and He—Ne lasers, LEDs, and the like. Further, exposure may be performed by a photoreceptor internal exposure method. The light used for the exposure is arbitrary. For example, the exposure may be performed using monochromatic light having a wavelength of 780 nm, monochromatic light having a wavelength of 600 nm to 700 nm, slightly short wavelength, or monochromatic light having a wavelength of 380 nm to 500 nm. . However, since light having a short wavelength of less than 600 nm cannot be sufficiently written due to absorption by the azobenzene derivative, exposure with monochromatic light of 600 nm to 850 nm is preferable.

  The type of the developing device 4 is not particularly limited, and an arbitrary device such as a dry development method such as cascade development, one-component insulating toner development, one-component conductive toner development, or two-component magnetic brush development, or a wet development method is used. be able to. In FIG. 1, the developing device 4 includes a developing tank 41, an agitator 42, a supply roller 43, a developing roller 44, and a regulating member 45, and is configured to store toner T inside the developing tank 41. . Further, a replenishing device (not shown) for replenishing the toner T may be attached to the developing device 4 as necessary. The replenishing device is configured to be able to replenish toner T from a container such as a bottle or a cartridge.

  The supply roller 43 is formed from a conductive sponge or the like. The developing roller 44 is made of a metal roll such as iron, stainless steel, aluminum, or nickel, or a resin roll obtained by coating such a metal roll with a silicone resin, a urethane resin, a fluorine resin, or the like. The surface of the developing roller 44 may be smoothed or roughened as necessary.

  The developing roller 44 is disposed between the electrophotographic photosensitive member 1 and the supply roller 43 and is in contact with the electrophotographic photosensitive member 1 and the supply roller 43, respectively. The supply roller 43 and the developing roller 44 are rotated by a rotation drive mechanism (not shown). The supply roller 43 carries the stored toner T and supplies it to the developing roller 44. The developing roller 44 carries the toner T supplied by the supply roller 43 and contacts the surface of the electrophotographic photosensitive member 1.

  The regulating member 45 is formed of a resin blade such as silicone resin or urethane resin, a metal blade such as stainless steel, aluminum, copper, brass, phosphor bronze, or a blade obtained by coating such metal blade with resin. The regulating member 45 contacts the developing roller 44 and is pressed against the developing roller 44 side with a predetermined force by a spring or the like (a general blade linear pressure is 5 to 500 g / cm). If necessary, the regulating member 45 may be provided with a function of imparting charging to the toner T by frictional charging with the toner T.

  The agitator 42 is rotated by a rotation driving mechanism, and agitates the toner T and conveys the toner T to the supply roller 43 side. A plurality of agitators 42 may be provided with different blade shapes and sizes.

  The type of the toner T is arbitrary, and besides the pulverized toner, a chemical toner produced by suspension granulation, suspension polymerization, emulsion polymerization aggregation method or the like can be used. In the case of chemical toners, those having a small particle size of about 4 to 8 μm are used, and those having various shapes are used, from those close to a spherical shape to those outside a spherical shape such as a potato shape or a rugby ball shape. be able to. In particular, the polymerized toner is excellent in charging uniformity and transferability, and is preferably used for improving image quality.

  The type of the transfer device 5 is not particularly limited, and an apparatus using an arbitrary system such as an electrostatic transfer method such as corona transfer, roller transfer, or belt transfer, a pressure transfer method, or an adhesive transfer method can be used. . Here, it is assumed that the transfer device 5 includes a transfer charger, a transfer roller, a transfer belt, and the like disposed so as to face the electrophotographic photoreceptor 1. The transfer device 5 applies a predetermined voltage value (transfer voltage) having a polarity opposite to the charging potential of the toner T, and transfers the toner image formed on the electrophotographic photosensitive member 1 to a recording paper (paper, medium) P. Is.

  There is no restriction | limiting in particular about the cleaning apparatus 6, Arbitrary cleaning apparatuses, such as a brush cleaner, a magnetic brush cleaner, an electrostatic brush cleaner, a magnetic roller cleaner, a blade cleaner, can be used. The cleaning device 6 is for scraping off residual toner adhering to the photoreceptor 1 with a cleaning member and collecting the residual toner. However, when there is little or almost no toner remaining on the surface of the photoreceptor, the cleaning device 6 may not be provided.

  The fixing device 7 includes an upper fixing member (fixing roller) 71 and a lower fixing member (fixing roller) 72, and a heating device 73 is provided inside the fixing member 71 or 72. FIG. 1 shows an example in which a heating device 73 is provided inside the upper fixing member 71. The upper and lower fixing members 71 and 72 include a fixing roll in which a metal base tube such as stainless steel or aluminum is coated with silicon rubber, a fixing roll in which Teflon (registered trademark) resin is coated, a fixing sheet, and the like. A member can be used. Further, the fixing members 71 and 72 may be configured to supply a release agent such as silicone oil in order to improve the releasability, or may be configured to forcibly apply pressure to each other by a spring or the like.

  When the toner transferred onto the recording paper P passes between the upper fixing member 71 and the lower fixing member 72 heated to a predetermined temperature, the toner is heated to a molten state and cooled after passing through the recording paper. Toner is fixed on P.

  The type of the fixing device is not particularly limited, and a fixing device of any type such as heat roller fixing, flash fixing, oven fixing, pressure fixing, etc. can be provided including those used here.

  In the electrophotographic apparatus configured as described above, an image is recorded as follows. That is, first, the surface (photosensitive surface) of the photoreceptor 1 is charged to a predetermined potential (for example, −600 V) by the charging device 2. At this time, charging may be performed with a DC voltage, or charging may be performed by superimposing an AC voltage on the DC voltage.

  Subsequently, the photosensitive surface of the charged photoreceptor 1 is exposed by the exposure device 3 according to the image to be recorded, and an electrostatic latent image is formed on the photosensitive surface. The developing device 4 develops the electrostatic latent image formed on the photosensitive surface of the photoreceptor 1.

  The developing device 4 thins the toner T supplied by the supply roller 43 with a regulating member (developing blade) 45 and has a predetermined polarity (here, the same polarity as the charging potential of the photosensitive member 1) and the negative polarity. ), And conveyed while being carried on the developing roller 44 to be brought into contact with the surface of the photoreceptor 1.

  When the charged toner T carried on the developing roller 44 comes into contact with the surface of the photoreceptor 1, a toner image corresponding to the electrostatic latent image is formed on the photosensitive surface of the photoreceptor 1. This toner image is transferred onto the recording paper P by the transfer device 5. Thereafter, the toner remaining on the photosensitive surface of the photoreceptor 1 without being transferred is removed by the cleaning device 6.

  After the transfer of the toner image onto the recording paper P, the final image is obtained by passing the fixing device 7 and thermally fixing the toner image onto the recording paper P.

  In addition to the above-described configuration, the image forming apparatus may be configured to perform, for example, a static elimination process. The neutralization step is a step of neutralizing the electrophotographic photosensitive member by exposing the electrophotographic photosensitive member, and a fluorescent lamp, an LED, or the like is used as the neutralizing device. In addition, the light used in the static elimination process is often light having an exposure energy that is at least three times that of the exposure light.

  Further, the image forming apparatus may be further modified and configured, for example, a configuration capable of performing processes such as a pre-exposure process and an auxiliary charging process, a structure performing offset printing, and a plurality of types. A full-color tandem system configuration using toner may be used.

  The electrophotographic photosensitive member 1 is used alone or in combination with one or more of the charging device 2, the exposure device 3, the developing device 4, the transfer device 5, the cleaning device 6, and the fixing device 7. An integrated cartridge (hereinafter referred to as an “electrophotographic photosensitive member cartridge” as appropriate) may be configured by being housed in a cartridge case configured to be detachable from the forming apparatus.

  In this case, for example, when the electrophotographic photosensitive member 1 and other members are deteriorated, the electrophotographic photosensitive member cartridge is removed from the main body of the image forming apparatus, and another new electrophotographic photosensitive member cartridge is mounted on the main body of the image forming apparatus. This facilitates maintenance and management of the image forming apparatus.

  Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples. In addition, the following examples are shown in order to explain the present invention in detail, and the present invention is not limited to the following examples unless it is contrary to the gist thereof. Note that the HPLC measurement and the mass spectrum measurement performed in the following production examples were performed under the measurement conditions described in the description of the above-described formula (B) and formula (C), respectively.

1. Compound synthesis (Production Example 1)
10 kg of tetraphenylbenzidine was suspended in 75 L of DMF, heated at 90 to 100 ° C., cooled to 70 ° C., and 18 kg of phosphorus oxychloride was added dropwise at a temperature of 70 ± 3 ° C. in a nitrogen stream. After reacting for 4 hours, it was cooled to 40 ° C. The reaction solution was added to a liquid mixture of 100 L of toluene and 100 L of water at 40 ° C. and separated. The obtained organic layer was washed with a sodium hydroxide aqueous solution and water, and then toluene was concentrated to obtain a formyl body.

  30 g of the obtained formyl form was suspended in 200 ml of THF, and 55 g of cinnamyl triphenylphosphonium chloride was added. The system was kept at 10 ° C., and 18 g of sodium methoxide (28% methanol solution) was added dropwise thereto at 0-10 ° C. After stirring at room temperature for 3.5 hours, the reaction solution was poured into a methanol-water (800 to 100 ml) mixed solution. The precipitated solid was collected by filtration and dried under reduced pressure (50 g). The dried solid was dissolved in a mixed solution of 200 ml of toluene / 50 ml of Isopar (registered trademark) E (manufactured by Exxon Chemical Co., Ltd.). The obtained solution was purified by column chromatography, dissolved in THF, and reprecipitated with methanol to obtain a yellow solid.

When the obtained yellow solid was analyzed using HPLC (detection light: 254 nm), (peak area of compound (1-a) in HPLC measurement / peak area of (compound 2-a) in HPLC measurement) was 62 compositions were found. Similarly, the yellow solid obtained by mass spectrum was analyzed. (Molecular ion peak intensity of compound (1-a) in mass spectrum measurement / molecular ion peak of compound (2-a) in mass spectrum measurement) It was found to be a composition having a strength of 27.
(Production Example 2)
100 g of tetraphenylbenzidine was suspended in 750 mL of DMF, heated at 90 to 100 ° C., cooled to 70 ° C., and 200 g of phosphorus oxychloride was added dropwise at a temperature of 74 ± 3 ° C. in a nitrogen stream. After reacting for 6 hours, it was cooled to 40 ° C. The reaction solution was added to a liquid mixture of 1 L of toluene and 1 L of water at 40 ° C. and separated. The obtained organic layer was washed with a sodium hydroxide aqueous solution and water, and then toluene was concentrated to obtain a formyl body.

  30 g of the obtained formyl form was suspended in 200 ml of THF, and 55 g of cinnamyl triphenylphosphonium chloride was added. The system was kept at 10 ° C., and 18 g of sodium methoxide (28% methanol solution) was added dropwise thereto at 0-10 ° C. After stirring at room temperature for 3.5 hours, the reaction solution was poured into a methanol-water (800 to 100 ml) mixed solution. The precipitated solid was collected by filtration and dried under reduced pressure (50 g). The dried solid was dissolved in a mixed solution of 200 ml of toluene / 50 ml of Isopar (registered trademark) E (manufactured by Exxon Chemical Co., Ltd.). The obtained solution was purified by column chromatography, dissolved in THF, and reprecipitated with methanol to obtain a yellow solid.

When the obtained yellow solid was analyzed using HPLC (detection light: 254 nm), (peak area of compound (1-a) in HPLC measurement / peak area of (compound 2-a) in HPLC measurement) was It was found to be 25 compositions. Similarly, the yellow solid obtained by mass spectrum was analyzed. (Molecular ion peak intensity of compound (1-a) in mass spectrum measurement / molecular ion peak of compound (2-a) in mass spectrum measurement) Strength) was found to be a composition of 13.
(Production Example 3)
100 g of tetraphenylbenzidine was suspended in 750 mL of DMF, heated at 90 to 100 ° C., cooled to 70 ° C., and 220 g of phosphorus oxychloride was added dropwise at a temperature of 76 ± 3 ° C. in a nitrogen stream. After reacting for 6 hours, it was cooled to 40 ° C. The reaction solution was added to a liquid mixture of 1 L of toluene and 1 L of water at 40 ° C. and separated. The obtained organic layer was washed with a sodium hydroxide aqueous solution and water, and then toluene was concentrated to obtain a formyl body.

  30 g of the obtained formyl form was suspended in 200 ml of THF, and 55 g of cinnamyl triphenylphosphonium chloride was added. The system was kept at 10 ° C., and 18 g of sodium methoxide (28% methanol solution) was added dropwise thereto at 0-10 ° C. After stirring at room temperature for 3.5 hours, the reaction solution was poured into a methanol-water (800 to 100 ml) mixed solution. The precipitated solid was collected by filtration and dried under reduced pressure (50 g). The dried solid was dissolved in a mixed solution of 200 ml of toluene / 50 ml of Isopar (registered trademark) E (manufactured by Exxon Chemical Co., Ltd.). The obtained solution was purified by column chromatography, dissolved in THF, and reprecipitated with methanol to obtain a yellow solid.

When the obtained yellow solid was analyzed using HPLC (detection light: 254 nm), (peak area of compound (1-a) in HPLC measurement / peak area of (compound 2-a) in HPLC measurement) was 11 compositions were found. Similarly, the yellow solid obtained by mass spectrum was analyzed. (Molecular ion peak intensity of compound (1-a) in mass spectrum measurement / molecular ion peak of compound (2-a) in mass spectrum measurement) It was found to be a composition having a strength of 8.5.
(Production Example 4)
100 g of tetraphenylbenzidine was suspended in 750 mL of DMF, heated at 90 to 100 ° C., cooled to 70 ° C., and 280 g of phosphorus oxychloride was added dropwise at a temperature of 80 ± 3 ° C. under a nitrogen stream. After reacting for 12 hours, it was cooled to 40 ° C. The reaction solution was added to a liquid mixture of 1 L of toluene and 1 L of water at 40 ° C. and separated. The obtained organic layer was washed with a sodium hydroxide aqueous solution and water, and then toluene was concentrated to obtain a formyl body.

  30 g of the obtained formyl form was suspended in 200 ml of THF, and 55 g of cinnamyl triphenylphosphonium chloride was added. The system was kept at 10 ° C., and 18 g of sodium methoxide (28% methanol solution) was added dropwise thereto at 0-10 ° C. After stirring at room temperature for 3.5 hours, the reaction solution was poured into a methanol-water (800 to 100 ml) mixed solution. The precipitated solid was collected by filtration and dried under reduced pressure (50 g). The dried solid was dissolved in a mixed solution of 200 ml of toluene / 50 ml of Isopar (registered trademark) E (manufactured by Exxon Chemical Co., Ltd.). The obtained solution was purified by column chromatography, dissolved in THF, and reprecipitated with methanol to obtain a yellow solid.

When the obtained yellow solid was analyzed using HPLC (detection light: 254 nm), (peak area of compound (1-a) in HPLC measurement / peak area of (compound 2-a) in HPLC measurement) was 4 composition was found. Similarly, the yellow solid obtained by mass spectrum was analyzed. (Molecular ion peak intensity of compound (1-a) in mass spectrum measurement / molecular ion peak of compound (2-a) in mass spectrum measurement) It was found to be a composition having a strength of 2.7.
(Production Example 5)
100 g of tetraphenylbenzidine was suspended in 750 mL of DMF, heated at 90 to 100 ° C., cooled to 70 ° C., and 350 g of phosphorus oxychloride was added dropwise at a temperature of 80 ± 3 ° C. in a nitrogen stream. After adding 10 g of zinc chloride and reacting for 12 hours, it was cooled to 40 ° C. The reaction solution was added to a liquid mixture of 1 L of toluene and 1 L of water at 40 ° C. and separated. The obtained organic layer was washed with a sodium hydroxide aqueous solution and water, and then toluene was concentrated to obtain a formyl body.

  30 g of the obtained formyl form was suspended in 200 ml of THF, and 55 g of cinnamyl triphenylphosphonium chloride was added. The system was kept at 10 ° C., and 18 g of sodium methoxide (28% methanol solution) was added dropwise thereto at 0-10 ° C. After stirring at room temperature for 3.5 hours, the reaction solution was poured into a methanol-water (800 to 100 ml) mixed solution. The precipitated solid was collected by filtration and dried under reduced pressure (50 g). The dried solid was dissolved in a mixed solution of 200 ml of toluene / 50 ml of Isopar (registered trademark) E (manufactured by Exxon Chemical Co., Ltd.). The obtained solution was purified by column chromatography, dissolved in THF, and reprecipitated with methanol to obtain a yellow solid.

  When the obtained yellow solid was analyzed using HPLC (detection light: 254 nm), (peak area of compound (1-a) in HPLC measurement / peak area of (compound 2-a) in HPLC measurement) was It was found to be a composition of 0.6. Similarly, the yellow solid obtained by mass spectrum was analyzed. (Molecular ion peak intensity of compound (1-a) in mass spectrum measurement / molecular ion peak of compound (2-a) in mass spectrum measurement) (Strength) was found to be a 0.4 composition.

(Comparative Production Example 1)
10 kg of tetraphenylbenzidine was suspended in 75 L of DMF, heated at 90 to 100 ° C., cooled to 70 ° C., and 8.3 kg of phosphorus oxychloride was added dropwise at a temperature of 70 ± 3 ° C. in a nitrogen stream. After reacting for 6 hours, it was cooled to 40 ° C. The reaction solution was added to a liquid mixture of 100 L of toluene and 100 L of water at 40 ° C. and separated. The obtained organic layer was washed with a sodium hydroxide aqueous solution and water, and then toluene was concentrated to obtain a formyl body.

  30 g of the obtained formyl form was suspended in 200 ml of THF, and 55 g of cinnamyl triphenylphosphonium chloride was added. The system was kept at 10 ° C., and 18 g of sodium methoxide (28% methanol solution) was added dropwise thereto at 0-10 ° C. After stirring at room temperature for 3.5 hours, the reaction solution was poured into a methanol-water (800 to 100 ml) mixed solution. The precipitated solid was collected by filtration and dried under reduced pressure (50 g). The dried solid was dissolved in a mixed solution of 200 ml of toluene / 50 ml of Isopar (registered trademark) E (manufactured by Exxon Chemical Co., Ltd.). The resulting solution was purified by column chromatography, then dissolved in THF, and reprecipitated with methanol to obtain 38 g of a yellow solid.

  When the obtained yellow solid was analyzed using HPLC (detection light: 254 nm), (peak area of compound (1-a) in HPLC measurement / peak area of (compound 2-a) in HPLC measurement) was 146 compositions were found. Similarly, the yellow solid obtained by mass spectrum was analyzed. (Molecular ion peak intensity of compound (1-a) in mass spectrum measurement / molecular ion peak of compound (2-a) in mass spectrum measurement) Strength) was found to be 128.

(Comparative Production Example 2)
The formyl body produced in Production Example 1 was purified by column chromatography to separate the formyl body represented by the following structural formula.

  30 g of the obtained formyl form was suspended in 200 ml of THF, and 55 g of cinnamyl triphenylphosphonium chloride was added. The system was kept at 10 ° C., and 18 g of sodium methoxide (28% methanol solution) was added dropwise thereto at 0-10 ° C. After stirring at room temperature for 3.5 hours, the reaction solution was poured into a methanol-water (800 to 100 ml) mixed solution. The precipitated solid was collected by filtration and dried under reduced pressure (50 g). The dried solid was dissolved in a mixed solution of 200 ml of toluene / 50 ml of Isopar E (manufactured by Exxon Chemical). The obtained solution was purified by column chromatography, dissolved in THF, and reprecipitated with methanol to obtain a yellow solid.

  When the obtained yellow solid was analyzed using HPLC (detection light: 254 nm), (peak area of compound (1-a) in HPLC measurement / peak area of (compound 2-a) in HPLC measurement) was It was found that the composition was 1000 or more (analysis limit) (compound (2-a) was not detectable). Similarly, when the yellow solid obtained by mass spectrum was analyzed, Compound (2-a) was not detectable.

(Comparative Production Example 3)
The formyl body produced in Production Example 1 was purified by column chromatography to separate the formyl body represented by the following structural formula.

  30 g of the obtained formyl form was suspended in 200 ml of THF, and 55 g of cinnamyl triphenylphosphonium chloride was added. The system was kept at 10 ° C., and 18 g of sodium methoxide (28% methanol solution) was added dropwise thereto at 0-10 ° C. After stirring at room temperature for 3.5 hours, the reaction solution was poured into a methanol-water (800 to 100 ml) mixed solution. The precipitated solid was collected by filtration and dried under reduced pressure (50 g). The dried solid was dissolved in a mixed solution of 200 ml of toluene / 50 ml of Isopar E (manufactured by Exxon Chemical). The obtained solution was purified by column chromatography, dissolved in THF, and reprecipitated with methanol to obtain a yellow solid.

  When the obtained yellow solid was analyzed using HPLC (detection light: 254 nm), (peak area of compound (1-a) in HPLC measurement / peak area of (compound 2-a) in HPLC measurement) was It was found that the composition was 0.001 or less (analysis limit) (compound (2-a) was not detectable). Similarly, when the yellow solid obtained by mass spectrum was analyzed, Compound (1-a) was not detectable.

(Comparative Production Example 4)
Synthesis was carried out in the same manner as in Production Example 2 except that N, N′-bis (3-methylphenyl) -N, N′-diphenyl-benzidine was used instead of tetraphenylbenzidine in Production Example 1, and the compound was A composition containing (1-x) and compound (2-x) was obtained. Here, the “compound (1-x)” is a mixture of the compound (1-b), the compound (1-c), and the compound (1-d) which are the exemplified compounds described above, -X) "is a mixture of compound (2-b), compound (2-c), and compound (2-d).

  When the composition was analyzed using HPLC (detection light: 254 nm), (the peak area of compound (1-x) in HPLC measurement / the peak area of (compound 2-x) in HPLC measurement) was 91. It turned out to be. Similarly, when the composition was analyzed by mass spectrum, (molecular ion peak intensity of compound (1-x) in mass spectrum measurement / molecular ion peak intensity of compound (2-x) in mass spectrum measurement) was It was found to be 85 compositions.

(Reference Production Example 1)
29 g of 1,3-diiminoisoindoline and 200 mL of sulfolane were mixed, 17 g of titanium tetraisopropoxide was added, and the mixture was reacted at 140 ° C. for 2 hours in a nitrogen atmosphere. After allowing to cool, the precipitate was filtered, washed with chloronaphthalene, further washed with 2% aqueous hydrochloric acid, water and methanol and dried. The dried solid was dissolved in 500 g of concentrated sulfuric acid, poured into 10 L of ice water, precipitated, and filtered to obtain a wet paste. 2 g of this paste was suspended in 30 mL of chlorobenzene and stirred at room temperature for 2 hours. The dispersion solution was filtered, washed with methanol, and dried under reduced pressure to obtain titania phthalocyanine crystals having a peak at a Bragg angle of 27.2 ° in the X-ray diffraction spectrum. Elemental analysis of this crystal revealed that 0.5% chlorine was contained.

(Reference Production Example 2)
29 g of 1,3-diiminoisoindoline and 200 mL of sulfolane were mixed, 17 g of titanium tetraisopropoxide was added, and the mixture was reacted at 140 ° C. for 2 hours in a nitrogen atmosphere. After allowing to cool, the precipitate was filtered, washed with chloronaphthalene, further washed with 2% aqueous hydrochloric acid, water and methanol and dried. The dried solid was dissolved in 500 g of concentrated sulfuric acid, poured into 10 L of ice water, precipitated, and filtered to obtain a wet paste. 2 g of this paste was suspended in 30 mL of THF and 3 mL of chlorobenzene and stirred at room temperature for 2 hours. The dispersion solution was filtered, washed with methanol, and dried under reduced pressure to obtain titania phthalocyanine crystals having a peak at a Bragg angle of 27.2 ° in the X-ray diffraction spectrum. Elemental analysis of this crystal revealed that 0.1% of chlorine was contained.

2. Preparation of electrophotographic photoreceptor (Example 1: Electrophotographic photoreceptor E1)
The undercoat layer dispersion prepared by the following method is dip-coated on the surface of an aluminum cylinder having an outer diameter of 30 mm, a length of 340 mm, and a thickness of 1.0 mm so that the film thickness after drying is 1 μm. An undercoat layer was provided.

  The undercoat layer dispersion was prepared by the following method. That is, a rutile type titanium oxide having an average primary particle size of 40 nm (“TTO55N” manufactured by Ishihara Sangyo Co., Ltd.) and 3% by mass of methyldimethoxysilane (“TSL8117” manufactured by Toshiba Silicone Co., Ltd.) with respect to the titanium oxide were flowed at high speed. Disperse the surface-treated titanium oxide obtained by mixing at high speed at a rotational peripheral speed of 34.5 m / sec with a ball mill of methanol / 1-propanol using a mixed kneader (“SMG300” manufactured by Kawata Co., Ltd.) Thus, a dispersion slurry of hydrophobized titanium oxide was obtained. The dispersion slurry, a mixed solvent of methanol / 1-propanol / toluene, and ε-caprolactam [compound represented by the following formula (a)] / bis (4-amino-3-methylcyclohexyl) methane [the following formula ( Compound represented by b)] / hexamethylenediamine [compound represented by the following formula (c)] / decamethylene dicarboxylic acid [compound represented by the following formula (d)] / octadecamethylene dicarboxylic acid [following formula The compound represented by (e)] has a composition molar ratio of 60% / 15% / 5% / 15% / 5% and is agitated and mixed with pellets of copolymerized polyamide to dissolve the polyamide pellets. Then, by performing ultrasonic dispersion treatment, the mass ratio of methanol / 1-propanol / toluene is 7/1/2, and the hydrophobically treated titanium oxide / copolymerized polymer Containing de mass ratio 3/1 was undercoat layer dispersion having a solid concentration of 18.0%.

  Next, as a charge generation material, 10 parts by mass of oxytitanium phthalocyanine produced in Reference Production Example 1 is added to 150 parts by mass of 1,2-dimethoxyethane, and pulverized and dispersed in a sand grind mill to prepare a pigment dispersion. did. 160 parts by mass of the pigment dispersion thus obtained was added to 100 parts by mass of a 5% 1,2-dimethoxyethane solution of polyvinyl butyral (manufactured by Denki Kagaku Kogyo Co., Ltd., trade name # 6000C), and an appropriate amount of 1,2 -Dimethoxyethane was added to finally prepare a dispersion having a solid content of 4.0%. This dispersion was dip-coated on the above undercoat layer so that the film thickness after drying was 0.4 μm, and then dried to form a charge generation layer.

  Next, 50 parts by mass of a yellow solid synthesized in Production Example 1 as a charge transport material, 100 parts by mass of polycarbonate having a structure represented by the following formula as a repeating unit as a binder, and 0.1% of silicone oil as a leveling agent. A solution in which 05 parts by mass is dissolved in 640 parts by mass of a tetrahydrofuran / toluene mixed solvent is dip-coated on the above-described charge generation layer so that the film thickness after drying is 26 μm. E1 was obtained.

（実施例２：電子写真感光体Ｅ２）
電荷輸送物質として、製造例１で合成した黄色固体のかわりに、製造例２で製造した黄色固体を使用する以外は、実施例１と同様にして電子写真感光体Ｅ２を得た。

(Example 2: Electrophotographic photoreceptor E2)
An electrophotographic photoreceptor E2 was obtained in the same manner as in Example 1 except that the yellow solid produced in Production Example 2 was used in place of the yellow solid synthesized in Production Example 1 as the charge transport material.

(Example 3: Electrophotographic photoreceptor E3)
An electrophotographic photosensitive member E3 was obtained in the same manner as in Example 1 except that the yellow solid produced in Production Example 3 was used in place of the yellow solid synthesized in Production Example 1 as the charge transport material.

(Example 4: Electrophotographic photoreceptor E4)
An electrophotographic photoreceptor E4 was obtained in the same manner as in Example 1 except that the yellow solid produced in Production Example 4 was used instead of the yellow solid synthesized in Production Example 1 as the charge transport material.

(Example 5: electrophotographic photoreceptor E5)
An electrophotographic photosensitive member E5 was obtained in the same manner as in Example 1, except that the yellow solid produced in Production Example 5 was used in place of the yellow solid synthesized in Production Example 1 as the charge transport material.

(Example 6: electrophotographic photoreceptor E6)
As a charge transport material, instead of the yellow solid synthesized in Production Example 1, a composition containing exemplary compound (1-u) and exemplary compound (2-u) (mass ratio (1-u) / (2-u) = 78) was used in the same manner as in Example 1 to obtain an electrophotographic photoreceptor E6.

(Example 7: electrophotographic photoreceptor E7)
As a charge transport material, instead of the yellow solid synthesized in Production Example 1, a composition containing the exemplified compound (1-q) and (exemplary compound 2-q) (mass ratio (1-q) / (2-q) = 78) was used in the same manner as in Example 1 to obtain an electrophotographic photoreceptor E7.

(Example 8: electrophotographic photoreceptor E8)
As a charge transport material, instead of the yellow solid synthesized in Production Example 1, a composition containing exemplary compound (1-1) and exemplary compound (2-1) (mass ratio (1-1) / (2-1) = 51) was used in the same manner as in Example 1 to obtain an electrophotographic photoreceptor E8.

(Example 9: electrophotographic photoreceptor E9)
An electrophotographic photoreceptor E9 was obtained in the same manner as in Example 1 except that the phthalocyanine synthesized in Reference Production Example 2 was used in place of the phthalocyanine synthesized in Reference Production Example 1 as the charge generation material.

(Example 10: electrophotographic photoreceptor E10)
Instead of 10 parts by mass of phthalocyanine synthesized in Reference Production Example 1 as charge generating materials, 10 parts by mass of phthalocyanine synthesized in Reference Production Example 2 and A-type phthalocyanine (Example Production of Japanese Patent Application No. 8-163133) According to method: Bragg angle (2θ ± 0.2 °) 9.3 °, 10.6 ° and 26.3 parts with diffraction peaks) An electrophotographic photoreceptor E10 was obtained.

(Comparative Example 1: Electrophotographic photoreceptor P1)
An electrophotographic photosensitive member P1 was obtained in the same manner as in Example 1 except that the yellow solid produced in Comparative Production Example 1 was used instead of the yellow solid synthesized in Production Example 1 as the charge transport material.

(Comparative Example 2: Electrophotographic photoreceptor P2)
An electrophotographic photosensitive member P2 was obtained in the same manner as in Example 1 except that the yellow solid produced in Comparative Production Example 2 was used instead of the yellow solid synthesized in Production Example 1 as the charge transport material.

(Comparative Example 3: Electrophotographic photoreceptor P3)
An electrophotographic photosensitive member P3 was obtained in the same manner as in Example 1 except that the yellow solid produced in Comparative Production Example 3 was used in place of the yellow solid synthesized in Production Example 1 as the charge transport material.

(Comparative Example 4: Electrophotographic photoreceptor P4)
An electrophotographic photoreceptor P4 was obtained in the same manner as in Example 1 except that the yellow solid produced in Comparative Production Example 4 was used instead of the yellow solid synthesized in Production Example 1 as the charge transport material.

(Comparative Example 5: electrophotographic photoreceptor P5)
Instead of the yellow solid synthesized in Production Example 1 as a charge transport material, a composition containing (1-pa) and (2-pa) represented by the following structure (mass ratio (1-pa) / (2-pa) ) = 77) except that the photoconductor was obtained in the same manner as in Example 1, but solid precipitation was observed, and the photoconductor could not be prepared. Therefore, the solvent was changed to dichloroethane to obtain an electrophotographic photoreceptor P5.

(Comparative Example 6: electrophotographic photoreceptor P6)
Instead of the yellow solid synthesized in Production Example 1 as a charge transport material, a composition containing (1-pa) and (2-pa) represented by the following structure (mass ratio (1-pa) / (2-pa) ) = 97) except that the photoconductor was obtained in the same manner as in Example 1, but solid precipitation was observed, and the photoconductor could not be prepared. Therefore, the solvent was changed to dichloroethane to obtain an electrophotographic photoreceptor P6.

3. Evaluation of electrophotographic photosensitive member (1) Electrical characteristic evaluation An electrophotographic characteristic evaluation apparatus (sequential electrophotographic technology) produced according to the standard of the Electrophotographic Society for the electrophotographic characteristics of the electrophotographic photosensitive members of Examples and Comparative Examples obtained above. (Electrical Photographic Society, edited by Corona, page 404-405), and the electrical characteristics were evaluated according to the following steps according to the following procedure: charging, exposure, potential measurement, and static elimination.

In an environment of a temperature of 25 ° C. and a humidity of 50%, the photosensitive member was charged so that the initial surface potential was −700 V, and a halogen lamp was irradiated with monochromatic light of 780 nm using an interference filter. Further, the post-exposure surface potential (VL) after 50 ms when the exposure was performed at an intensity of 1.0 μJ / cm ² was measured (−V). Further, after charging so that the initial surface potential of the photosensitive member becomes −700 V, the photosensitive member was left in a dark place for 2.5 seconds, and the attenuation value DD (V) of the surface potential was examined. The results are shown in Table 1. The value shown in the column “VL (−V)” in Table 1 is the absolute value of the residual potential (VL). A small value of “VL (−V)” (that is, an absolute value of the residual potential (VL)) means that the residual potential is low.

  In addition, on the drums of the electrophotographic photosensitive members of the respective examples and comparative examples obtained as described above, a hole having a length of 20 mm and a width of 40 mm is formed in order to form a portion exposed by the light of a white fluorescent lamp and a portion not exposed. Cover the entire surface of the photoconductor with black paper that has been opened, and then apply light from a white fluorescent lamp (“Neolmi Super (registered trademark) FL20SS · W / 18” manufactured by Mitsubishi OSRAM) to the light on the photoconductor surface. The intensity was adjusted to 2000 lux, and irradiation was performed for 10 minutes centering on the portion of the black paper having a hole. After that, the black paper is removed, and the drum is mounted on a cyan cartridge for forming a cyan image in a tandem type color page printer ("SPEDIA (registered trademark) N5" manufactured by Casio Co., Ltd.), which is written and exposed with a 740 nm LED. A half-tone solid image was printed out, and an image formation evaluation test was conducted to examine whether there was a difference in image density between the light-exposed portion and the unexposed portion. The results are also shown in Table 1.

  As is apparent from Table 1, the electrophotographic photoreceptors of Examples 1 to 5, 8, and 9 showed a low residual potential of 60 V or less in absolute value despite the fast process of 50 ms, and the chargeability was also high. Good and light resistance is ensured. On the other hand, the electrophotographic photoreceptors of Comparative Examples 1 to 4 using charge transport materials having the same skeleton have poor light resistance and are inferior in balance with electrical characteristics. In particular, in the photoconductor of Comparative Example 3, the chargeability and electrical characteristics are very poor. The same can be said for the comparison between the electrophotographic photoreceptors of Examples 6 and 7 using the same skeleton charge transport material and Comparative Example 5. In view of the above, by making the ratio of the compounds represented by the general formula (1) and the general formula (2) contained in the photosensitive layer within the scope of the present invention, an electron in which low residual potential and light resistance are compatible. It turns out that it can be set as a photographic photoreceptor.

  Although the present invention has been described with reference to the most practical and preferred embodiments at the present time, the invention is not limited to the embodiments disclosed herein. The electrophotographic photosensitive member, the electrophotographic photosensitive member cartridge, and the image forming apparatus with such a change can also be changed as appropriate without departing from the spirit or concept of the invention that can be read from the claims and the entire specification. It should be understood as encompassed within the technical scope of the invention.

1 is a schematic diagram illustrating a main configuration of an embodiment of an image forming apparatus of the present invention.

Explanation of symbols

1 Photoconductor (Electrophotographic photoconductor)
2 Charging device (charging roller; charging unit)
3 Exposure equipment (exposure section)
4 Development device (development unit)
5 Transfer device 6 Cleaning device (cleaning part)
7 Fixing Device 41 Developing Tank 42 Agitator 43 Supply Roller 44 Developing Roller 45 Regulating Member 71 Upper Fixing Member (Fixing Roller)
72 Lower fixing member (fixing roller)
73 Heating device T Toner P Recording paper (paper, medium)

Claims (7)

An electrophotographic photoreceptor having a photosensitive layer on a conductive support, wherein the photosensitive layer contains a compound represented by the following general formula (1) and a compound represented by the following general formula (2), and An electrophotographic photoreceptor, wherein the content ratio of the compound represented by the general formula (1) and the compound represented by the general formula (2) in the photosensitive layer is represented by the following formula (A).
80> (mass of compound represented by general formula (1) / mass of compound represented by general formula (2))> 0 (A)

(In the general formulas (1) and (2), R ^{1 to} R ⁵ represent a hydrogen atom, an alkyl group which may have a substituent, or an aryl group which may have a substituent, and X Represents an organic residue having 20 to 60 carbon atoms, and n represents an integer of 0 to 2. An electrophotographic photoreceptor having a photosensitive layer on a conductive support, wherein the photosensitive layer contains a compound represented by the following general formula (1) and a compound represented by the following general formula (2), and An electrophotographic photoreceptor, wherein the content ratio of the compound represented by the general formula (1) and the compound represented by the general formula (2) in the photosensitive layer is represented by the following formula (B).
80> (peak area of the compound represented by the general formula (1) in high performance liquid chromatography measurement (detection light wavelength 254 nm) / the compound represented by the general formula (2) in high performance liquid chromatography measurement (detection light wavelength 254 nm) Peak area)> 0 (B)

(In the general formulas (1) and (2), R ^{1 to} R ⁵ represent a hydrogen atom, an alkyl group which may have a substituent, or an aryl group which may have a substituent, and X Represents an organic residue having 20 to 60 carbon atoms, and n represents an integer of 0 to 2. An electrophotographic photoreceptor having a photosensitive layer on a conductive support, wherein the photosensitive layer contains a compound represented by the following general formula (1) and a compound represented by the following general formula (2), and An electrophotographic photoreceptor, wherein a content ratio of the compound represented by the general formula (1) and the compound represented by the general formula (2) in the photosensitive layer is represented by the following formula (C).
80> (Molecular ion peak intensity of compound represented by general formula (1) in mass spectrum measurement / Molecular ion peak intensity of compound represented by general formula (2) in mass spectrum measurement)> 0 (C)

(In the general formulas (1) and (2), R ^{1 to} R ⁵ represent a hydrogen atom, an alkyl group which may have a substituent, or an aryl group which may have a substituent, and X Represents an organic residue having 20 to 60 carbon atoms, and n represents an integer of 0 to 2. The photosensitive layer contains phthalocyanine, and the total content of chlorine (elements) of the phthalocyanine is 0.6% by mass or less. Electrophotographic photoreceptor. In the X-ray diffraction spectrum, a diffraction peak is shown at a Bragg angle (2θ ± 0.2 °) of 27.3 °, or a diffraction peak is shown at 9.3 °, 10.6 °, and 26.3 °. The electrophotographic photosensitive member according to claim 1, comprising oxytitanium phthalocyanine. 6. The electrophotographic photosensitive member according to claim 1, a charging unit that charges the electrophotographic photosensitive member, and an exposure unit that exposes the charged electrophotographic photosensitive member to form an electrostatic latent image. And an image forming apparatus comprising: a developing unit that develops the electrostatic latent image formed on the electrophotographic photosensitive member. The electrophotographic photosensitive member according to any one of claims 1 to 5, a charging unit that charges the electrophotographic photosensitive member, an exposure unit that exposes the charged electrophotographic photosensitive member to form an electrostatic latent image, An electrophotographic photosensitive member cartridge comprising: at least one developing unit that develops an electrostatic latent image formed on the electrophotographic photosensitive member.

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