JP2002268255A - Electrophotographic photoreceptor, process cartridge and electrophotographic device having photoreceptor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrophotographic photoreceptor capable of forming an ultra-high resolution image. SOLUTION: This electrophotographic photoreceptor is constituted by successively laminating a photoreceptive layer and a surface protective layer on a conductive supporting body and provided with a short wavelength light absorbing layer between the conductive supporting body and the photoreceptive layer, and realizes write-in by 400 to 450 nm wavelength.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic photosensitive member used for a copying machine, a printer, a facsimile and the like, a process cartridge using the same, and an electrophotographic apparatus.
More specifically, a recording density of 12 to meet the demand for higher image quality
The present invention relates to an ultra-high resolution electrophotographic photosensitive member capable of at least 00 dots / inch, a process cartridge and an electrophotographic apparatus using the same, and furthermore, an electrophotographic photosensitive member capable of stably obtaining high image quality under high durability. And a process cartridge and an electrophotographic apparatus using the same.

[0002]

2. Description of the Related Art An electrophotographic photosensitive member conventionally used in an electrophotographic system (hereinafter, may be simply referred to as a photosensitive member).
As inorganic photoconductors, various inorganic and organic photoconductors are known. The "electrophotographic method" as used herein generally means that a photoconductive photoreceptor is first charged in a dark place, for example, by corona discharge, and then subjected to image exposure to selectively dissipate the charge of only the exposed portion and statically. A so-called Carlson process, in which an electrostatic latent image is obtained, and this latent image portion is developed with a toner composed of a colorant such as a dye or a pigment and a polymer material to visualize and form an image. This is an image forming process.

A photoreceptor using an organic photoconductor has a higher degree of freedom in a photosensitive wavelength range, film formability, flexibility, film transparency, mass productivity, toxicity, and cost than an inorganic photoconductor. At present, most photoconductors use organic photoconductors because of their advantages. The photoreceptor used repeatedly in this electrophotographic method and similar processes must have excellent electrostatic characteristics such as sensitivity, receptive potential, potential holding property, potential stability, residual potential, and spectral sensitivity characteristics. Required.

[0004] In recent years, the development of information processing system machines using the electrophotographic system has been remarkable. In particular, a printer using a digital recording method of converting information into a digital signal and recording information by light has remarkably improved in print quality and reliability. This digital recording method is applied not only to printers but also to ordinary copying machines, and so-called digital copying machines have been developed. Further, since the digital copier is added with various information processing functions, its demand is expected to increase in the future.

[0005] The electrophotographic photoreceptors currently used in these systems generally have a charge generation layer formed directly or via an intermediate layer on a conductive support, and a charge transport layer provided thereon. The so-called function-separated type photoreceptor is mainly used. Further, a surface protective layer is formed on the outermost surface of the photoreceptor for improving mechanical or chemical durability. In this function-separated type photoconductor, when the photoconductor whose surface is charged is exposed, light passes through the charge transport layer and is absorbed by the charge generation material in the charge generation layer. The charge generating material absorbs this light to generate charge carriers. The generated charge carriers are injected into the charge transport layer and move in the charge transport layer along the electric field generated by the charging to neutralize the surface charge of the photoreceptor. As a result, an electrostatic latent image is formed on the surface of the photoconductor. Therefore, the function-separated type photoreceptor mainly has a charge generation material that absorbs from the near infrared to the visible part and does not hinder the transmission of the absorbed light of the charge generation material, that is, from the visible part (yellow light region) to the ultraviolet. A combination with a charge transport material having absorption is often used.

As a light source compatible with such a digital recording method, for example, a small, inexpensive and highly reliable semiconductor laser (LD) or light emitting diode (LED) is often used. The oscillation wavelength range of the LD most frequently used at present is in the near-infrared light region around 780 to 800 nm. The emission wavelength of a typical LED is at 740 nm.

On the other hand, recently, violet to blue short wavelength LDs and LEDs having an oscillation wavelength of 400 to 450 nm have been developed and listed as write light sources corresponding to the digital recording method. For example, when a short-wavelength LD whose oscillation wavelength is about half that of a conventional near-infrared region LD is used as a writing light source, the spot diameter of the laser beam on the photosensitive member is expressed by the following equation (3). Can be reduced significantly in theory. Therefore, they are very advantageous for increasing the writing density of the latent image, that is, the resolution. d∝ (π / 4) (λf / D) (3) (where d is the spot diameter on the photoconductor, λ is the wavelength of the laser beam, f is the focal length of the fθ lens, and D is the lens diameter)

Further, the short wavelength LD and LED have advantages such as reduction in size of an electrophotographic apparatus including an optical system and speeding up of an electrophotographic method.
A highly sensitive and stable electrophotographic photosensitive member corresponding to an LD or LED oscillation light source of 0 to 450 nm is required.

However, current electrophotographic devices are 300 to
The resolution was about 600 dpi, which was not enough for a photographic image. For this reason, a higher resolution electrophotographic apparatus is desired, and development for it is being performed. To increase the resolution, it is effective to reduce the minimum dot diameter. For that purpose, an image exposure means with a smaller beam diameter, an electrophotographic photosensitive member that enables a small potential latent image, and a reproducible Developing means for developing is required.

However, an electrophotographic apparatus that satisfies all of them has not yet been developed. Conventionally, a small, inexpensive and highly reliable semiconductor laser (L
D) and light emitting diodes (LEDs) are often used.
The oscillation wavelength range of the currently most frequently used LD is 780-
It is in the near infrared light region near 800 nm. The beam spot diameter is about 150 to 60 μm. A dot diameter of about 30 μm or 2400 equivalent to 1200 dpi
In order to narrow down the dot diameter to about 15 μm corresponding to dpi, an ultra-high precision optical component and a large optical member are required, and it has not been possible to commercialize both in terms of cost and space. To solve this problem, it is considered effective to shorten the wavelength of the light source, and an electrophotographic apparatus using a short wavelength laser has been proposed (Japanese Patent Laid-Open No. 19598/1993).
However, an ultra-high resolution image could not be obtained only by reducing the beam diameter in this way.

An electrophotographic photoreceptor used in a conventional electrophotographic apparatus generally has a charge generation layer formed on a conductive support, and a so-called function-separated type laminated photoreceptor having a charge transport layer provided thereon. The body is mainstream. Further, a surface protective layer may be formed on the outermost surface of the photoconductor in order to improve mechanical or chemical durability.

In this function-separated type photoreceptor, when the photoreceptor whose surface is charged is exposed, light passes through the charge transport layer and is absorbed by the charge generation material in the charge generation layer.
The charge generating material absorbs this light to generate charge carriers.
The generated charge carriers are injected into the charge transport layer and move in the charge transport layer along the electric field generated by the charging to neutralize the surface charge of the photoreceptor. As a result, an electrostatic latent image is formed on the surface of the photoconductor. Therefore, a charge generation material having absorption from the near infrared region to the visible region,
A combination with a charge transporting material that does not hinder the transmission of the absorbed light of the charge generating material, that is, has an absorption from the visible portion (yellow light region) to the ultraviolet region, is often used. When such an electrophotographic photosensitive member is used, light having a very short wavelength such as 400 to 450 nm is absorbed by the charge transporting layer and has a disadvantage that the sensitivity is reduced. For this purpose, an electrophotographic apparatus using a charge transport material having relatively low absorption has been proposed.

[0013] Even if the charge generation layer of the electrophotographic photosensitive member can be irradiated with light having a small beam diameter, it is still difficult to form a super-resolution image. As the image formation speeds up and digitization proceeds, the energy density of the light-irradiated portion increases, and the charge density generated in the charge generation layer of the electrophotographic photosensitive member increases. Charges generated at high density are diffused in the plane direction while moving through the charge transport layer to the photoreceptor surface,
Even if the beam diameter was narrowed, the electrostatic latent image formed on the photoreceptor became large.

To solve this problem, it is effective to reduce the thickness of the charge transport layer of the electrophotographic photoreceptor. The dot reproducibility was deteriorated due to the unevenness of the electric potential due to the life and unevenness of the conductive support, and it was very difficult to realize it.
Under such circumstances, an electrophotographic apparatus having an ultra-high resolution has not yet been provided on the market.

On the other hand, as an electrophotographic photosensitive member used in an electrophotographic apparatus, a single-layer type having a photosensitive layer mainly composed of a charge generating material, a charge transporting material and a binder provided on a conductive support is known. Are known. This photoreceptor is advantageous for ultra-high resolution electrophotography because charge generation due to light irradiation occurs at the surface of the photoreceptor, so that the spread of the electrostatic latent image is reduced. However, the sensitivity and residual potential characteristics are inferior to the function-separated type photoreceptor, and there remains a problem for an electrophotographic apparatus that requires high speed.

Also, an inverse layer type electrophotographic photosensitive member in which a charge transport layer and a charge generation layer are laminated on a conductive support in this order is known. Also in this case, since the charge is generated at the surface of the photoreceptor, the spread of the electrostatic latent image is reduced, which is advantageous for ultra-high resolution electrophotography. For example, JP-A-9-24
No. 0051 discloses an electrophotographic apparatus using an LD having an oscillation wavelength of 400 to 500 nm as a light source. However, in this photoconductor layer configuration, a fragile thin-film charge generation layer is formed on the outermost surface, which is susceptible to mechanical and chemical hazards due to charging, development, transfer, and cleaning means. This is not practical because the deterioration of remarkably occurs.

In order to extend the life, a reverse layer photoreceptor having a surface protective layer has been proposed (Japanese Patent Laid-Open No. 1-1709).
No. 51). In this case, the aim is to provide an electrophotographic apparatus that reduces the amount of generated ozone and has a small environmental load, and has not been designed as a photoconductor for an ultra-high resolution electrophotographic apparatus. An electrophotographic apparatus compatible with high durability has not been provided in an image forming process repeatedly performed with high image quality, particularly in color image formation requiring color reproducibility and persistence.

As described above, there has been proposed a configuration for preventing the spread of an electrostatic latent image as an electrophotographic photosensitive member. However, in an image forming process including toner development and transfer, the beam diameter of an image exposure unit is reduced. An electrophotographic apparatus which forms an ultra-high resolution image, has high speed, and has excellent durability cannot be provided only by considering the spread of the electrostatic latent image of the electrophotographic photosensitive member.

When a high resolution of 400 dpi or more is required, in an apparatus such as the present invention using coherent light such as a semiconductor laser or a light emitting diode as the exposure light, the thickness of the photosensitive layer of the electrophotographic photosensitive member is reduced. The problem that an interference fringe pattern due to a deviation or the like appears in an image becomes very prominent, and it is required to solve this problem. Also, when trying to design a photoreceptor in consideration of high image quality, regarding the charge generation layer in the function separation type using the existing charge generation material, the absorbance of the charge generation layer with respect to the image exposure light source wavelength of the present invention is When the absorbance is small, especially when the absorbance is 2.0 or less, there is a disadvantage that interference fringes are easily generated. On the other hand, a method of simply increasing the thickness of the charge generation layer or increasing the concentration of the charge generation material can be considered. However, there is a problem that the charge potential is easily reduced due to repeated use.

Further, Japanese Patent Application Laid-Open No. Hei 3-62039 and the like have taken measures against interference fringes by roughening the surface of the conductive substrate. However, if the surface is too rough, a problem of poor cleaning may occur. Would. Further, Japanese Patent Laid-Open No. 7-1
JP-A-60028 discloses an attempt to suppress interference fringes by adding a dye or the like to an undercoat layer or a photosensitive layer. However, conventionally known cyanine dyes and the like have a large photodegradation and are not sufficient to achieve the purpose. Effect cannot be expected.

[0021]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an exposure light source for an image exposing means using a semiconductor laser or a light emitting diode having an oscillation wavelength in the range of 400 to 450 nm. Even when the absorbance of the charge generation layer with respect to the wavelength is small, it is possible to prevent the generation of interference fringes due to light passing through the charge generation layer, and to form an ultra-high-resolution image of 1200 dpi or more, and even 2400 dpi, and high durability. An object of the present invention is to provide an electrophotographic apparatus capable of stably obtaining high image quality.

[0022]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned drawbacks and problems of the prior art. An electrophotographic apparatus having at least an electrophotographic photosensitive member, a charging means, an image exposure means and a developing means is provided. Wherein the wavelength of the writing light source of the image exposure means is a semiconductor laser or a light emitting diode having an oscillation wavelength in the range of 400 to 450 nm, and the electrophotographic photoreceptor has a short wavelength absorbing layer, a photosensitive layer and a surface protective layer on a conductive substrate. And the surface roughness of the conductive support is 0.02 μm to 1.5 μm in Rz value.
And the surface roughness of the short-wavelength light absorbing layer is 0.02 μm or more and 1.5 μm or less in Rz value, and the surface roughness of the outermost surface of the photosensitive layer is 0.02 μm or more in Rz value and 1 .
An electrophotographic apparatus characterized by having a thickness of 5 μm or less is provided.

The photoreceptor in the present apparatus satisfies the demand for ultra-high resolution image formation to achieve high image quality, and realizes stable toner development and transfer under high durability. It is. That is, in order to achieve high image quality, the image exposure means and the photosensitive layer of the electrophotographic photosensitive member are devised. By absorbing the light with the absorption layer, the generation of interference fringes is suppressed, and high image quality is achieved. Further, the surface roughness of the conductive support is not less than 0.02 μm and not more than 1.5 μm in Rz value, and the surface roughness of the short wavelength light absorbing layer is not more than 0.02 μm in Rz value.
When the surface roughness of the outermost surface of the photosensitive layer is at least 0.02 μm and at most 1.5 μm in Rz value, the light transmitted through the charge generation layer can be reduced by the short wavelength light absorbing layer. The interference fringes can be reduced as much as possible by the synergistic effect.

[0024]

BEST MODE FOR CARRYING OUT THE INVENTION As the photosensitive layer of the electrophotographic photosensitive member of the present invention, typical layer constitutions are shown below, but the invention is not limited thereto. As shown in FIG.
A short wavelength light absorbing layer 2 is formed thereon, a charge generation layer 3 is formed, a charge transport layer 4 is formed on the charge generation layer, and a protective layer 5 is provided on the charge transport layer. In the case of employing this configuration, the protective layer and the charge transport layer are required to have a sufficient transmittance for writing light. More specifically, 50 to monochromatic light in the wavelength range of 390 to 460 nm is used.
%. The thickness of the charge transport layer and the protective layer should be as small as possible in order to prevent carriers generated in the charge generation layer from diffusing in the process of moving through the charge transport layer and the protective layer and hindering formation of an ultra-high resolution image. It is better to make it thin. However, in order to achieve high durability, the protective layer needs to have a thickness of 1 to 3 μm, and the charge transport layer has a thickness of 5 to 15 μm, depending on conditions such as development.
μm is appropriate.

The charge transport function has a hole transport function and an electron transport function. When used for the charge transport layer, these materials may be used alone or a mixture of both functional materials may be used.However, when the protective layer also has a charge transport function, it is better to have the same function as the charge transport layer. good.

The components of each layer will be described below.
As the conductive support, aluminum, nickel, copper,
Metal plate of titanium, gold, stainless steel, etc., metal drum or metal foil, plastic film on which aluminum, nickel, copper, titanium, gold, tin oxide, indium oxide, etc. are deposited, or paper or plastic film coated with conductive material Alternatively, a drum or the like may be used. Materials other than the above include metals and alloys such as iron, silver, zinc, lead, tin, antimony, and indium, or oxides of the metals, carbon, and conductive polymers. A conductive support obtained by molding or forming the conductive material on an appropriate substrate by coating, vapor deposition, etching, plasma treatment, or the like can be used.

The surface roughness of the conductive support is an Rz value of 0.0
The range is from 2 μm to 1.5 μm. When the surface roughness of the conductive support is smaller than 0.02 μm, scattering of laser light is reduced and image defects such as interference fringes are easily caused, and adhesion to the photosensitive layer is weakened and peeling is caused. It causes image defects such as white spots. The surface roughness is 1.
If the thickness exceeds 5 μm, unevenness of the potential on the surface of the photosensitive layer is caused to deteriorate dot reproducibility, and pinholes are generated in the photosensitive layer due to abnormal discharge, and image defects such as black spots occur.

The short-wavelength light-absorbing layer formed on the conductive substrate of the present invention generally comprises a resin as a main component. However, considering that these resins are coated with a photosensitive layer with a solvent, It is desirable that the resin has high solvent resistance to general organic solvents. Examples of such a resin include water-soluble resins such as polyvinyl alcohol, casein, and sodium polyacrylate, copolymer-soluble nylons, alcohol-soluble resins such as methoxymethylated nylon, polyurethane, melamine resins, phenol resins, alkyd-melamine resins, and epoxy resins. Curable resins that form a three-dimensional network structure, such as resins, are exemplified. Further, for preventing interference fringes and optimizing the resistance value, a fine powder pigment of a metal oxide exemplified by titanium oxide, silica, alumina, zirconium oxide, tin oxide, indium oxide and the like may be added. These short-wavelength light-absorbing layers can be formed using an appropriate solvent and a coating method. Further, silane coupling agents, titanium coupling agents, chromium coupling agents, and the like can also be used. In addition, known materials can be used.

The surface roughness of the short-wavelength light-absorbing layer is set to an Rz value of 0.1.
The range is from 02 μm to 1.5 μm. When the surface roughness of the short-wavelength light-absorbing layer is smaller than 0.02 μm, scattering of laser light is reduced and image defects such as interference fringes are easily caused, and adhesion to the charge generating layer is weakened, and peeling is performed. To cause image defects such as white spots. When the surface roughness exceeds 1.5 μm, potential unevenness on the surface of the photosensitive layer is caused to reduce dot reproducibility, and pinholes are generated in the photosensitive layer due to abnormal discharge, and image defects such as black spots are generated. Or occur.

The short wavelength light absorbing layer contains the following short wavelength light absorbing material in a binder. As the short-wavelength light-absorbing material, a so-called n-type pigment having an electron transporting property,
Examples include an electron transport material, a chelate dye, and an ultraviolet absorber.

Examples of the so-called n-type pigments exhibiting electron transport properties include organic pigments exhibiting n-type semiconductor characteristics such as perylene pigments, thioindigo pigments, quinacridone pigments, dioxazine pigments, disazo pigments, and trisazo pigments. Among them, those having high absorbance for monochromatic light in the wavelength region of 390 to 460 nm are particularly preferably used.

Examples of the electron transporting material include chloranil, bromanil, tetracyanoethylene, tetracyanoquinodimethane, 2,4,7-trinitro-9-fluorenone, and 2,4,5,7-tetranitro-9-fluorenone. 2,4,5,7-tetranitroxanthone,
2,4,8-trinitrothioxanthone, 2,6,8-
Trinitro-indeno 4H-indeno [1,2-b] thiophen-4-one, 1,3,7-trinitrodibenzothiophene-5,5-dioxide, oxadiazole derivative, (2,3-diphenyl-1 -Indenylidene)
Malononitrile, dinitrobenzene, dinitroanthracene, malononitrile, thiopyran-based compounds, benzoquinone, quinones such as diphenoquinone, stilbenequinone and derivatives thereof, dinitroanthracene, dinitroacridine, nitroanthraquinone, dinitroanthraquinone, succinic anhydride, maleic anhydride, dibromo anhydride Maleic acid and the like can be mentioned, and a diphenoquinone derivative and an electron transporting substance shown in the following formula can be suitably used. These charge transport materials can be used alone or
You may mix and use more than one kind.

Embedded image (Wherein R ¹ , R ² and R ³ represent a hydrogen atom, a halogen atom,
Represents a substituted or unsubstituted alkyl group, an alkoxy group, or a substituted or unsubstituted phenyl group, which may be the same or different; )

Examples of the chelate dye include an indoaniline dye, an azomethine dye, a phthalocyanine dye, and an azo dye. These dyes have a group capable of forming a chelate in the molecule.

Examples of the ultraviolet absorber include known benzophenone-based, benzotriazole-based, cyanoacrylate-based, and triazine-based ultraviolet absorbers. When these are used in combination with HALS, a so-called light stabilizer, for example, a hindered amine-based light stabilizer, light deterioration is also prevented, and it can be suitably used for the purpose of the present invention.

The thickness of the short wavelength light absorbing layer is 1 to 10 μm.
m is appropriate. When the film thickness of the short-wavelength light-absorbing layer is less than 1 μm, problems such as abnormal images due to the surface of the conductive support are likely to occur, and when the film thickness exceeds 10 μm, the generation and accumulation of residual potential And the fluctuation of the photoconductor potential increases.

The charge generation layer can be provided by dissolving or dispersing the charge generation material in an appropriate solvent, if necessary, adding a binder resin, coating, and drying. As a dispersion method of the dispersion liquid for the charge generation layer, for example,
Examples thereof include a ball mill, an ultrasonic wave, and a homomixer. Examples of the application means include a dipping coating method, a blade coating method, and a spray coating method.

When the photosensitive layer is formed by dispersing the charge generating material, the charge generating material should have an average particle diameter of 1 μm or less, preferably 0.5 μm or less, in order to improve the dispersibility in the layer. preferable. In addition, the smaller the better, the better for high image quality and small dot reproducibility. However, the above-mentioned particle size is too small to be easily agglomerated, and the preservation of the dispersion liquid is deteriorated by re-agglomeration, the resistance of the layer is increased, and the crystal defects are increased and the sensitivity and the repetition characteristics are reduced, Alternatively, since there is a limit in miniaturization, the lower limit of the average particle size is preferably set to 0.01 μm.

The thickness of the charge generation layer is preferably from 0.1 to 2 μm.

As the charge generation material, conventionally known materials can be used, and examples thereof include the following pigments. As organic pigments, for example, C.I. Pigment Blue 25 (Color Index CI 21180), C.I. Pigment Red 41 (CI. 21200), C.I. Acid Red 52 (CI. 45100), C.I. Pigments (described in JP-A-53-95033), azo pigments having a distyrylbenzene skeleton (JP-A-53-133445), and azo pigments having a triphenylamine skeleton (JP-A-53-132347) Azo pigments having a dibenzothiophene skeleton (described in JP-A-54-21728), and azo pigments having an oxadiazole skeleton (described in JP-A-54-12742).
Azo pigments having a fluorenone skeleton (described in JP-A-54-22834), azo pigments having a bisstilbene skeleton (described in JP-A-54-17733), distyryl oxadiazole An azo pigment having a skeleton (described in JP-A-54-2129) and an azo pigment having a distyrylcarbazole skeleton (described in JP-A-52-129)
In addition to azo pigments such as azo pigments having a benzanthrone skeleton, for example, CI Pigment Blue 16 (CI 74100), Y-type oxotitanium phthalocyanine (Japanese Patent Application Laid-Open No. 64-1706).
No. 6), A (β) -type oxotitanium phthalocyanine, B (α) -type oxotitanium phthalocyanine, I-type oxotitanium phthalocyanine (JP-A-11-214)
No. 66), chlorogallium phthalocyanine type II (Iijima et al., Chemical Society of Japan 67th Spring Annual, 1B4,04)
(1994)), V-type hydroxygallium phthalocyanine (Daimon et al., Chemical Society of Japan 67th Spring Annual, 1B4,05)
(1994)), phthalocyanine-based pigments such as X-type metal-free phthalocyanine (U.S. Pat. No. 3,816,118), C-Ivat Brown 5 (CI 73410),
Examples include indico-based pigments such as CI butt die (CI 73030) and perylene pigments such as Argoscarlet B (manufactured by Bayer) and Insence Scarlet R (manufactured by Bayer). These charge generating materials may be used alone or in combination of two or more.

As the solvent used for preparing the dispersion or solution of the charge generation layer, for example, N, N-dimethylformamide, toluene, xylene, monochlorobenzene, 1,2-dichloroethane, 1,1,1- Examples thereof include trichloroethane, dichloromethane, 1,1,2-trichloroethane, trichloroethylene, tetrahydrofuran, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, ethyl acetate, butyl acetate, and dioxane.

As the binder resin, any conventionally known binder resin having good insulating properties can be used, and there is no particular limitation. For example, polyethylene, polyvinyl butyral, polyvinyl formal, polystyrene resin, phenoxy resin, polypropylene, acrylic resin, methacrylic resin, vinyl chloride resin, vinyl acetate resin, epoxy resin, polyurethane resin, phenol resin, polyester resin, alkyd resin, polycarbonate resin, Polyamide resin, silicone resin, addition polymerization type resin such as melamine resin, polyaddition type resin, polycondensation type resin,
And copolymer resins containing two or more of the repeating units of these resins, such as vinyl chloride-vinyl acetate copolymer, styrene-acryl copolymer, vinyl chloride-vinyl acetate-maleic anhydride copolymer resin, and the like. In addition to the insulating resin described above, a polymer organic semiconductor such as poly-N-vinyl carbazole may be used. These binders can be used alone or
It can be used as a mixture of more than one kind. The amount of the binder resin is suitably 0 to 5 parts by weight, preferably 0.1 to 3 parts by weight, per 1 part by weight of the charge generating material.

As the charge transport layer, conventionally known ones can be used. When the charge transport layer is laminated on the surface side of the charge generation layer, it is necessary to transmit monochromatic light in the wavelength range of 400 to 450 nm. Preferred examples in that case are as follows.

Specific examples of the binder resin used for the charge transport layer include polystyrene, styrene-acrylonitrile copolymer, styrene-butadiene copolymer, styrene-maleic anhydride copolymer, polyester, polyvinyl chloride, and chloride. Vinyl-vinyl acetate copolymer, polyvinyl acetate, polyvinylidene chloride, polyarylate, phenoxy resin, polycarbonate, cellulose acetate resin, ethyl cellulose resin, polyvinyl butyral, polyvinyl formal, polyvinyl toluene, poly-N-vinyl carbazole, acrylic resin, Thermoplastic or thermosetting resins such as silicone resin, epoxy resin, melamine resin, urethane resin, phenol resin, and alkyd resin are exemplified.

Among them, a binder resin represented by the following general formula (Chemical Formula 2) and / or (Chemical Formula 3), a polymer alloy resin of a polyarylate resin or a polyarylate resin and a polycarbonate resin, a polyarylate resin and a polyethylene terephthalate resin Are suitable.

Embedded image

Embedded image (R ₄ , R ₅ , R ₆ , and R ₇ each independently represent a hydrogen atom, a substituted or unsubstituted alkyl group or a halogen atom, or a substituted or unsubstituted aryl group. X represents an aliphatic 2 Y represents a single bond, a linear, branched or cyclic alkylene group having 1 to 12 carbon atoms, -O-, -S-, -SO-,- SO ₂
—, —CO—, —CO—O—Z—O—CO— (wherein Z represents an aliphatic divalent group) or

Embedded image (In the formula, a is an integer of 1 to 20, b is an integer of 1 to 2000, R ₈ and R ₉ represent a substituted or unsubstituted alkyl group or an aryl group. Here, R ₈ and R ₉ represent P and q represent compositions, and 0.1 ≦ p ≦ 1;
0 ≦ q ≦ 0.9, n represents the number of repeating units, and is 5 to 500.
Which is an integer of 0). Specific examples include those having the following structures, but are not limited thereto.

[0045]

[Table 1]

[0046]

[Table 2]

The charge transporting material used in the charge transporting layer of the present invention includes a hole transporting material and an electron transporting material. These include the following.

As the hole transporting material, for example, poly-N
Carbazole and its derivatives, poly-γ-carbazolylethyl glutamate and its derivatives, pyrene-formaldehyde condensate and its derivatives, polyvinylpyrene,
There are polyvinylphenanthrene, oxazole derivatives, imidazole derivatives, triphenylamine derivatives, and compounds represented by the following general formula.

[0049]

Embedded image (Wherein, R ¹ represents a methyl group, an ethyl group, a 2-hydroxyethyl group or a 2-chloroethyl group, R ² represents a methyl group, an ethyl group, a benzyl group or a phenyl group;
³ represents a hydrogen atom, a chlorine atom, a bromine atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, a dialkylamino group or a nitro group. )

[0050]

Embedded image (Wherein, Ar represents a naphthalene ring, an anthracene ring, a pyrene ring and a substituted product thereof, a pyridine ring, a furan ring,
Represents a thiophene ring, and R represents an alkyl group, a phenyl group or a benzyl group. )

[0051]

Embedded image (Wherein, R ¹ represents an alkyl group, a benzyl group, a phenyl group, or a naphthyl group; R ² represents a hydrogen atom, a carbon number of 1 to 3;
Represents an alkyl group, an alkoxy group having 1 to 3 carbon atoms, a dialkylamino group, a diaralkylamino group or a diarylamino group, n represents an integer of 1 to 4, and when n is 2 or more, even if R ² is the same, It may be different. R ³ represents a hydrogen atom or a methoxy group. )

[0052]

Embedded image (In the formula, R ¹ represents an alkyl group, a substituted or unsubstituted phenyl group or a heterocyclic group 1 to 11 carbon atoms, R ^2,
R ³ may be each the same or different, represent a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, a hydroxyalkyl group, a chloroalkyl group, or a substituted or unsubstituted aralkyl group, also, R ² and R ³ It may combine with each other to form a nitrogen-containing heterocyclic ring. R ⁴ may be the same or different and represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group or a halogen atom. )

[0053]

Embedded image (Wherein, R represents a hydrogen atom or a halogen atom;
Represents a substituted or unsubstituted phenyl group, naphthyl group, anthryl group or carbazolyl group. )

[0054]

Embedded image (Wherein, R ¹ represents a hydrogen atom, a halogen atom, a cyano group, an alkoxy group having 1 to 4 carbon atoms or an alkyl group having 1 to 4 carbon atoms, and Ar is

Embedded image (R ² represents an alkyl group having 1 to 4 carbon atoms, R ³ represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms or a dialkylamino group; When n is 2, R ³ may be the same or different, and R ⁴ and R ⁵ are a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 4 carbon atoms or a substituted or unsubstituted alkyl group. Represents a substituted benzyl group).

[0055]

Embedded image Wherein R is a carbazolyl group, a pyridyl group, a thienyl group, an indolyl group, a furyl group or a substituted or unsubstituted phenyl group, a styryl group, a naphthyl group, or an anthryl group, and these substituents are dialkylamino Group, alkyl group, alkoxy group, carboxy group or ester thereof, halogen atom, cyano group, aralkylamino group, N-alkyl-N-aralkylamino group, amino group, nitro group and acetylamino group Represents a group.)

[0056]

Embedded image (Wherein, R ¹ represents a lower alkyl group, a substituted or unsubstituted phenyl group, or a benzyl group, and R ² represents a hydrogen atom, a lower alkyl group, a lower alkoxy group, a halogen atom, a nitro group, an amino group, or a lower alkyl group. Represents an amino group substituted with a benzyl group or a benzyl group, and n represents an integer of 1 or 2.)

[0057]

Embedded image (Wherein, R ¹ represents a hydrogen atom, an alkyl group, an alkoxy group or a halogen atom, and R ² and R ³ represent an alkyl group,
Represents a substituted or unsubstituted aralkyl group or a substituted or unsubstituted aryl group, R ⁴ represents a hydrogen atom, a lower alkyl group or a substituted or unsubstituted phenyl group, and Ar represents a substituted or unsubstituted phenyl group or Represents a naphthyl group. )

[0058]

Embedded image (Wherein, n is an integer of 0 or 1, R ¹ represents a hydrogen atom, an alkyl group or a substituted or unsubstituted phenyl group,
Ar ¹ represents a substituted or unsubstituted aryl group; R ⁵ represents an alkyl group containing a substituted alkyl group, or a substituted or unsubstituted aryl group;

Embedded image9-anthryl group or substituted or unsubstituted carbazo
Represents a aryl group, where R ^TwoRepresents a hydrogen atom, an alkyl group,
Alkoxy group, halogen atom or

Embedded image (However, R ³ and R ⁴ represent an alkyl group, a substituted or unsubstituted aralkyl group or a substituted or unsubstituted aryl group, R ³ and R ⁴ may be the same or different, and R ⁴ forms a ring When m is 2 or more, R ² may be the same or different.) When n is 0, A and R
¹ may form a ring together. )

[0059]

Embedded image (In the formula, R ¹ , R ² and R ³ represent a hydrogen atom, a lower alkyl group, a lower alkoxy group, a halogen atom or a dialkylamino group, and n represents 0 or 1.)

[0060]

Embedded image (Wherein R ¹ and R ² represent an alkyl group containing a substituted alkyl group, or a substituted or unsubstituted aryl group;
Represents a substituted amino group, a substituted or unsubstituted aryl group or an allyl group. )

[0061]

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

[0062]

Embedded image (Wherein, R ¹ represents a lower alkyl group, a lower alkoxy group or a halogen atom, and R ² and R ³ may be the same or different and represent a hydrogen atom, a lower alkyl group, a lower alkoxy group or a halogen atom; l, m, and n represent an integer of 0 to 4.)

[0063]

Embedded image (Wherein R ¹ , R ³ and R ⁴ are a hydrogen atom, an amino group, an alkoxy group, a thioalkoxy group, an aryloxy group, a methylenedioxy group, a substituted or unsubstituted alkyl group,
R ² represents a hydrogen atom, an alkoxy group, a substituted or unsubstituted alkyl group or a halogen atom; Where R
¹ , R ² , R ³ and R ⁴ are excluded unless they are all hydrogen atoms. Further, k, l, m and n are integers of 1, 2, 3 or 4, and when each is an integer of 2, 3 or 4,
R ¹ , R ² , R ³ and R ⁴ may be the same or different. )

[0064]

Embedded image (Wherein, Ar represents a condensed polycyclic hydrocarbon group having 18 or less carbon atoms which may have a substituent, and R ¹ and R ² represent a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl Group, an alkoxy group, a substituted or unsubstituted phenyl group, which may be the same or different, and n is 1
Alternatively, it represents an integer of 2. )

[0065]

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

Embedded image (However, Ar represents a substituted or unsubstituted aromatic hydrocarbon group, and R ¹ and R ² are a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group.)
Represents )

[0066]

Embedded image (Wherein, Ar represents a substituted or unsubstituted aromatic hydrocarbon group, R represents a hydrogen atom, a substituted or unsubstituted alkyl group,
Or a substituted or unsubstituted aryl group. n is 0
Or, 1 and m are 1 or 2, and when n = 0 and m = 1, Ar and R may form a ring together. )

The compounds represented by the general formula 5 include, for example, 9-ethylcarbazole-3-aldehyde-1-methyl-1-phenylhydrazone, 9-ethylcarbazole-3-aldehyde-1-benzyl-1-benzyl. Phenylhydrazone, 9-ethylcarbazole-3-aldehyde-
Examples include 1,1-diphenylhydrazone.

The compound represented by the general formula 6 includes, for example, 4-diethylaminostyryl-β-aldehyde-1
-Methyl-1-phenylhydrazone, 4-methoxynaphthalene-1-aldehyde-1-benzyl-1-phenylhydrazone and the like.

Compounds represented by the general formula 7 include, for example, 4-methoxybenzaldehyde-1-methyl-1-
Phenylhydrazone, 2,4-dimethoxybenzaldehyde-1-benzyl-1-phenylhydrazone, 4-diethylaminobenzaldehyde-1,1-diphenylhydrazone, 4-methoxybenzaldehyde-1- (4-
Methoxy) phenylhydrazone, 4-diphenylaminobenzaldehyde-1-benzyl-1-phenylhydrazone, 4-dibenzylaminobenzaldehyde-1,1
-Diphenylhydrazone and the like.

The compounds represented by the general formula 8 include, for example, 1,1-bis (4-dibenzylaminophenyl) propane, tris (4-diethylaminophenyl) methane, 1,1-bis (4-diphenyl (Benzylaminophenyl) propane, 2,2-dimethyl-4,4-bis (diethylamino) -triphenylmethane and the like.

The compounds represented by the general formula 9 include, for example, 9- (4-diethylaminostyryl) anthracene and 9-bromo-10- (4-diethylaminostyryl) anthracene.

The compounds represented by the general formula 10 include, for example, 9- (4-dimethylaminobenzylidene) fluorene and 3- (9-fluorenylidene) -9-ethylcarbazole.

Examples of the compound represented by the general formula 12 include 1,2-bis (4-diethylaminostyryl) benzene and 1,2-bis (2,4-dimethoxystyryl) benzene.

Compounds represented by the general formula (13) include, for example, 3-styryl-9-ethylcarbazole, 3- (4
-Methoxystyryl) -9-ethylcarbazole and the like.

Compounds represented by general formula 14 include, for example, 4-diphenylaminostilbene, 4-dibenzylaminostilbene, 4-ditolylaminostilbene,
-(4-diphenylaminostyryl) naphthalene, 1-
(4-Diethylaminostyryl) naphthalene and the like.

The compound represented by the general formula 15 includes, for example, 4'-diphenylamino-α-phenylstilbene, 4'-bis (4-methylphenyl) amino-α-phenylstilbene and the like.

The compound represented by the general formula 18 includes, for example, 1-phenyl-3- (4-diethylaminostyryl) -5- (4-diethylaminophenyl) pyrazolin.

The compound represented by the general formula 19 includes, for example, 2,5-bis (4-diethylaminophenyl)-
1,3,4-oxadiazole, 2-N, N-diphenylamino-5- (4-diethylaminophenyl) -1,
3,4-oxadiazole, 2- (4-dimethylaminophenyl) -5- (4-diethylaminophenyl)-
1,3,4-oxadiazole and the like.

The compound represented by the general formula 20 includes, for example, 2-N, N-diphenylamino-5- (N-ethylcarbazol-3-yl) -1,3,4-oxadiazole, -(4-diethylaminophenyl) -5- (N
-Ethylcarbazol-3-yl) -1,3,4-oxadiazole and the like.

The benzidine compound represented by the general formula (21) includes, for example, N, N-diphenyl-N, N-bis (3
-Methylphenyl)-[1,1-biphenyl] -4,4
-Diamine and 3,3-dimethyl-N, N, N, N-tetrakis (4-methylphenyl)-[1,1-biphenyl] -4,4-diamine.

Examples of the biphenylylamine compound represented by the general formula 22 include 4-methoxy-N, N-diphenyl- [1,1-biphenyl] -4-amine and 4-methyl-N, N- Bis (4-methylphenyl)-[1,1-
Biphenyl] -4-amine, 4-methoxy-N, N-bis (4-methylphenyl)-[1,1-biphenyl]-
4-amine, N, N-bis (3,4-dimethylphenyl)-[1,1-biphenyl] -4-amine and the like.

The triarylamine compound represented by the general formula (23) includes, for example, 1-diphenylaminopyrene,
1-di (p-tolylamino) pyrene, N, N-di (p-
Tolyl) -1-naphthylamine, N, N-di (p-tolyl) -1-phenanthrylamine, 9,9-dimethyl-
2- (di-p-tolylamino) fluorene, N, N,
N, N-tetrakis (4-methylphenyl) -phenanthrene-9,10-diamine, N, N, N, N-tetrakis (3-methylphenyl) -m-phenylenediamine and the like.

The diolefin aromatic compounds represented by the general formula (24) include, for example, 1,4-bis (4-diphenylaminostyryl) benzene, 1,4-bis [4-
Di (p-tolyl) aminostyryl] benzene. Examples of the styrylpyrene compound represented by the general formula 23 include 1- (4-diphenylaminostyryl) pyrene, 1- [4-di (p-tolyl) aminostyryl] pyrene, and the like.

Examples of the polymer type charge transport material include poly-N-carbazole derivatives, poly-γ-carbazolylethyl glutamate derivatives, pyrene-formaldehyde condensate derivatives, polyvinylpyrene, polyvinylphenanthrene, oxazole derivatives, imidazole derivatives, Acetophenone derivatives (described in JP-A-7-325409), distyrylbenzene derivatives, diphenethylbenzene derivatives (described in JP-A-9-127713),
α-phenylstilbene derivatives (JP-A-9-29741)
No. 9), butadiene derivatives (JP-A-9-80)
No. 783), hydrogenated butadiene (Japanese Unexamined Patent Publication No.
80784), diphenylcyclohexane derivatives (described in JP-A-9-80772), and distyryltriphenylamine derivatives (described in JP-A-9-22274).
0), diphenyldistyrylbenzene derivatives (described in JP-A-9-265197 and JP-A-9-265201), and stilbene derivatives (described in JP-A-9-2118).
No. 77), m-phenylenediamine derivatives (described in JP-A-9-304957 and JP-A-9-304957), resorcinol derivatives (described in JP-A-9-32990)
No. 7), triarylamine derivatives (JP-A-64-9964, JP-A-7-199503, JP-A-8-176293, JP-A-8-208820, JP-A-8-253568, JP-A-8-253568) 8-269446, JP-A-3-221522, JP-A-4-11627, JP-A-4-183719, JP-A-4-124163,
JP-A-4-320420, JP-A-4-316543
JP-A-5-310904, JP-A-7-56374
JP-A-8-62864, U.S. Pat.
8,090 and 5,486,439).

One example of these polymer type charge transport materials (P1
To P27), but the format is not limited to a homopolymer, a random copolymer, an alternating copolymer, or a block copolymer.

[0086]

[Table 3]

[0087]

[Table 4]

[0088]

[Table 5]

[0089]

[Table 6]

[0090]

[Table 7]

[0091]

[Table 8]

These charge transporting materials may be used alone or in combination of two or more. The amount of the charge transporting material is suitably 20 to 300 parts by weight, preferably 40 to 150 parts by weight, based on 100 parts by weight of the binder resin. Examples of the solvent used for forming the charge transport layer include tetrahydrofuran,
Dioxane, toluene, dichloromethane, monochlorobenzene, dichloroethane, cyclohexanone, methyl ethyl ketone, acetone and the like are used.

Since the surface protective layer is formed above the charge transport layer, it is naturally necessary to absorb as little as possible monochromatic irradiation light in the wavelength range of 400 to 450 nm. Materials used are ABS resin, ACS resin,
Olefin-vinyl monomer copolymer, chlorinated polyether, allyl resin, phenol resin, polyacetal,
Polyamide, polyamide imide, polyacrylate, polyallyl sulfone, polybutylene, polybutylene terephthalate, polycarbonate, polyether sulfone,
Resins such as polyethylene, polyethylene terephthalate, polyimide, acrylic resin, polymethylbenten, polypropylene, polyphenylene oxide, polysulfone, polystyrene, AS resin, butadiene-styrene copolymer, polyurethane, polyvinyl chloride, polyvinylidene chloride, and epoxy resin Can be

For the purpose of improving abrasion resistance, a fluorine resin such as polytetrafluoroethylene, a silicone resin, and an inorganic or organic filler having high hardness can be added to these resins. The average particle size of these fillers is 0.02 μm to 3 μm, preferably 0.05 to 1 μm. If the particle size is smaller than this, the abrasion resistance of the surface protective layer becomes weak, and a long-life image forming apparatus cannot be obtained. When the particle size is large, light scattering causes a reduction in resolution.

Specific examples of the filler include titanium oxide,
Tin oxide, zinc oxide, zirconium oxide, indium oxide, silicon nitride, calcium oxide, barium sulfate, IT
One or a mixture of O, silica, colloidal silica, alumina, carbon black, fine powder of fluorine resin, fine powder of polysiloxane resin, and fine powder of polymer charge transport material can be given.

These fillers may be surface-treated with an inorganic substance or an organic substance for reasons such as improvement in dispersibility and improvement in surface properties. In general, those treated with a silane coupling agent as a water-repellent treatment, those treated with a fluorinated silane coupling agent, those treated with a higher fatty acid or copolymerized with a polymer material, etc., are used. Which are treated with alumina, zirconia, tin oxide, or silica.

The filler is pulverized or dispersed as it is with the binder resin and / or the charge transport material and the dispersing solvent, and coated as a photosensitive layer. The content of the filler in the formed surface protective layer is 5 to 50% by weight, preferably 10 to 40% by weight, and if it is 10% by weight or less, it is not sufficient in terms of abrasion resistance. If it is present, the transparency of the surface protective layer is impaired, resulting in a decrease in sensitivity. The average particle size is 0.02 to 3.0 μm, preferably 0.1 to 3.0 μm.
It is preferable to pulverize and disperse the particles to a size of from 0.5 to 1.0 μm. If the particle size is large, the cueing cleaning blade is damaged on the surface, resulting in poor cleaning and poor image quality.

Examples of the dispersion solvent include methyl ethyl ketone, acetone, methyl isobutyl ketone, ketones such as cyclohexanone, ethers such as dioxane, tetrahydrofuran and ethyl cellosolve, aromatics such as toluene and xylene, halogens such as chlorobenzene and dichloromethane, and ethyl acetate. And esters such as butyl acetate. When a pulverizing step is added, a ball mill, a sand mill, a vibration mill or the like is used.

Further, in the above-mentioned photosensitive layer and / or protective layer, a phenol compound, a hydroquinone compound, a hindered phenol compound, a hindered amine compound, a hindered amine and a hindered phenol are contained in the same molecule for the purpose of improving chargeability and the like. Existing compounds and the like can be added.

Further, a plasticizer and a leveling agent may be added. As the plasticizer, those used as general plasticizers for general resins such as dibutyl phthalate and dioctyl phthalate can be used as they are, and the amount of the plasticizer is suitably about 0 to 30% by weight based on the binder resin. As the leveling agent, silicone oils such as dimethyl silicone oil and methylphenyl silicone oil, and polymers or oligomers having a perfluoroalkyl group in a side chain are used. 1% by weight is suitable.

The contact angle of pure water on the surface of the electrophotographic photosensitive member of the present invention is preferably 90 ° or more. It is more preferably at least 95 °. When the contact angle with pure water is 90 ° or more, a reduction in the surface energy of the photoconductor is achieved. If the contact angle of the photoreceptor surface to pure water is less than 90 °, the charge product and the debris brought from the toner or paper are liable to adhere to the surface by repeated use by the electrophotographic process. The deterioration of the latent image (image deletion) is likely to occur. On the other hand, if the contact angle with pure water is too large, then the development stability of the photoconductor and the toner becomes insufficient.

In order to make the contact angle of pure water on the surface of the electrophotographic photosensitive member 90 ° or more, for example, a silicone structure such as a dimethylsilicone part or a methylphenylsilicone part, a perfluoroalkyl structure, a long-chain alkyl structure or the like is used. Use a polymer that has Alternatively, a fine powder of a fluorine resin, a fine powder of a polysiloxane resin, silicone oil, a wax having an ester group, a higher fatty acid, or the like is added to the photoreceptor. Alternatively, it is achieved by applying or supplying these. Further, these methods may be used in combination to enhance the effect.

Here, as mentioned above, F / C and Si / C mean that a material having a silicone structure or a perfluoroalkyl structure increases the contact angle and lowers the surface energy of the photoreceptor. It is a very effective material. Therefore, by defining this value, it is possible to prevent adverse effects such as defective cleaning. Where F
If / C and Si / C are smaller than 0.01, the surface energy is high and the effect is not sufficient, and if / C and Si / C are larger than 1.00, the development stability of the toner becomes insufficient. Here, XPS (X-ray photoelectron spectroscopy), which is a method of measuring the ratio of atoms, is a 1600S type manufactured by PHI, uses MgKα (200 W) as an X-ray source, and measures an area of 0.8 × 2 mm. The average was obtained at 10 points.

In order to form the surface protective layer with at least a layer made of a curable resin, various cross-linking reactions known in the field of materials can be used. The reaction includes radical polymerization,
Ion polymerization, thermal polymerization, photopolymerization, radiation polymerization, plasma C
The VD method, the photo CVD method, and the like are well known. For example, JP-A-2-132456, JP-A-11-28
JP-A-8121, JP-A-11-265085, JP-A-11-212291, JP-A-2000-664
No. 33 publication.

A material having a charge-transporting function or a polymer-type charge-transporting material may be subjected to a cross-linking reaction so as to have a charge-transporting function. For these, for example,
JP-A-2000-147814, JP-A-2000-1
The materials and methods described in JP-A-47804 and JP-A-2000-122322 can be used.

In order to realize a hardened protective layer having a low surface energy, for example, a silicone structure, a perfluoroalkyl structure, or a long-chain structure can be obtained by the methods disclosed in JP-A-11-95474 and JP-A-2000-131860. A material having a chain alkyl structure or the like may be subjected to a crosslinking reaction.

The mechanism for controlling the abrasion of the photosensitive member is as follows.
JP-A-8-20226, JP-A-11-21239
No. 8, JP-A-11-219087, JP-A-11-219087
1-311928, JP-A-2000-047523
JP, JP-A-2000-098838, JP-A-20
There is a method described in, for example, JP-A-00-147946. These include zinc stearate, silicone oil, fluorine-based oil, fluorine-containing polymers, and the like as lubricants, and apply and / or supply these lubricants to the surface of the photoreceptor to form an extremely thin film. This provides an electrophotographic apparatus having low surface energy, low wear and high image quality.

As the charging means, known means such as a corotron, a scorotron, a solid state charger (solid state charger) and a charging roller are used. A method in which the surface of the conductive roller (including an object having a protective layer on the surface) is brought into direct contact with the surface of the member to be charged, and a voltage is applied to the roller to charge the surface of the member to be charged, or the surface of the member to be charged is contacted. A method is used in which a charging member is brought into contact, and a voltage is applied to the contact charging member to charge the surface of the member to be charged.

As the image exposure means, a semiconductor laser or light emitting diode having an oscillation wavelength in the range of 400 to 450 nm of the writing light source is used. When a semiconductor laser is used, the main components of the image exposure means are a semiconductor laser (LD), an aperture, a collimating lens, a main CYL, a sub CYL, a polygon mirror, a scanning lens 1, a scanning lens 2, and a mirror. L
D is controlled at an image frequency of 65 MHz or more, preferably 100 MHz or more, and more preferably 130 MHz.
z or more. In addition, temperature compensation control is performed, and the rotation speed of the polygon mirror is 50 Krpm or more, preferably 60 Krpm.
m or more. The light source is preferably used with multiple beams, at least two channels, preferably more than four channels.

As a developing means, a conventionally known developing device can be used. For example, a contact development method or a non-contact development method can be used. The non-contact development method refers to a method in which a gap is provided between the electrostatic image bearing member and the developer bearing member with a thickness equal to or greater than the thickness of the developer layer, and an electric field is applied to visualize the image. The developing voltage may be DC, AC or DC + AC. AC development refers to a method in which an electrostatic latent image holding member and a developer carrying member are opposed to each other and an alternating electric field is applied to visualize the image. At this time, the average particle size of the toner used is 4 to 8 μm, and the toner may be a pulverized toner or a polymerized toner. In the case of a polymerized toner, a toner produced by a method of polymerizing a composition containing a monomer and a colorant, or a composition containing a prepolymer and a colorant in a liquid medium, or if necessary, physically or Represents chemically treated toners and developers containing these toners.

Next, the electrophotographic method and the electrophotographic apparatus of the present invention will be described in detail with reference to the drawings.

FIG. 2 is a schematic diagram for explaining the electrophotographic apparatus of the present invention, and the following modified examples also belong to the category of the present invention. In FIG. 2, a photosensitive member 1 is provided with a photosensitive layer in which a short-wavelength light absorbing layer, a charge generation layer, a charge transport layer, and a surface protective layer are sequentially laminated on a conductive support. The photoconductor 1 has a drum shape, but may have a sheet shape or an endless belt shape. Charger 3, pre-transfer charger 7, transfer charger 1
0, separation charger 11, charger 1 before cleaning
For 3, known means such as a corotron, a scorotron, a solid state charger (solid state charger), and a charging roller are used.

As the transfer means, the above-mentioned charger can be generally used, but as shown in the figure, a combination of a transfer charger and a separation charger is effective.

For the image exposure section 5, a semiconductor laser having an oscillation wavelength in the range of 400 to 450 nm is used. In addition, as a light source such as the static elimination lamp 2, a general light emitting material such as a fluorescent lamp, a tungsten lamp, a halogen lamp, a mercury lamp, a sodium lamp, a light emitting diode (LED), a semiconductor laser (LD), and electroluminescence (EL) is used. Can be. To irradiate only light in a desired wavelength range, various filters such as a sharp cut filter, a band pass filter, a near infrared cut filter, a dichroic filter, an interference filter, and a color temperature conversion filter can be used.

The light source and the like are provided with a transfer step, a charge removal step, a cleaning step, and a pre-exposure step using light irradiation in addition to the step shown in FIG.
Light is applied to the photoconductor.

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

A known method is applied to the developing means, and a known method is also used for the charge removing means.

FIG. 3 shows another example of the electrophotographic process according to the present invention. The photoreceptor 21 has the photosensitive layer of the present invention, is driven by drive rollers 22a and 22b, is charged by the charger 23, is exposed to light by the light source 24, is developed (not shown), and is transferred by the charger 25. Exposure before cleaning by 26, cleaning by brush 27, light source 2
8 is repeatedly performed. In FIG. 3, the photosensitive member 21 (in this case, the support is light-transmitting in this case) is irradiated with light for pre-cleaning exposure from the support side.

The above illustrated electrophotographic process is an example of the embodiment of the present invention, and other embodiments are of course possible. For example, although the pre-cleaning exposure is performed from the support side in FIG. 3, this may be performed from the photosensitive layer side, or the image exposure and the irradiation of the static elimination light may be performed from the support side.

On the other hand, the light irradiation step includes image exposure, pre-cleaning exposure, and charge elimination exposure. However, in addition to this, a pre-transfer exposure, a pre-exposure of image exposure, and other known light irradiation steps are provided. Light irradiation can also be performed on the body.

The image forming means as described above may be fixedly incorporated in a copying apparatus, a facsimile, or a printer, or may be incorporated in the apparatus in the form of a process cartridge. The process cartridge is configured such that at least one of a photoconductor, a charging unit, a developing unit, and a cleaning unit is integrally formed and is detachable from the apparatus main body. There are many shapes and the like of the process cartridge. As a general example, the one shown in FIG.

[0122]

The present invention will be described below with reference to examples.
The present invention is not limited by the embodiments. All parts are parts by weight.

(Example 1) Oil-free alkyd resin (manufactured by Dainippon Ink and Chemicals, Inc .: Beccolite M6401)
A mixture of 1.5 parts, 1 part of a melamine resin (manufactured by Dainippon Ink and Chemicals, Super Beckamine G-821), 3 parts of dibromoanthanethrone, and 22.5 parts of 2-butanone was placed in a ball mill pot, and a φ10 mm alumina ball was taken. Was used for ball milling for 48 hours to prepare a coating solution for the short wavelength light absorbing layer. This coating solution is applied on an aluminum cylinder cut at a feed rate of 0.2 mm / rev and having a surface roughness Rz value of 0.5 μm, dried at 130 ° C. for 20 minutes, and irradiated with a short-wavelength light having a thickness of about 2.5 μm. An absorption layer was obtained. The surface roughness of the short-wavelength light-absorbing layer was measured using a surface roughness shape measuring device Surfcom 570A manufactured by Tokyo Seimitsu Co., Ltd., at a measuring distance of 2.5 m
m, at a scanning speed of 0.3 mm / sec, R
The z value was 0.3.

Next, 500 parts of a 0.5% tetrahydrofuran solution containing 7.5 parts of a bisazo compound represented by the following structural formula (a) and 2.5 parts of a polyester resin (Vylon 200, manufactured by Toyobo Co., Ltd.) was ground in a ball mill. After mixing, the resulting dispersion was applied onto the short-wavelength light-absorbing layer and air-dried to form a charge generation layer.

Embedded image

Next, as a charge transporting material, 7 parts of a charge transporting material represented by the following structural formula (b) and 10 parts of a polycarbonate resin (Panlite C-1400, manufactured by Teijin Limited) were dissolved in tetrahydrofuran. A coating solution is applied on the charge generation layer, and the coating solution is applied at 80 ° C. for 2 minutes,
After drying at 0 ° C. for 20 minutes, a charge transport layer having a thickness of about 14 μm was formed.

Embedded image

Next, 8 parts of the polymer-type charge transport material represented by the exemplified compound (P9) and 3 parts of polytetrafluoroethylene particles (average primary particle size: 0.3 μm) were dissolved in 40 parts of THF and 140 parts of cyclohexanone. This protective layer coating solution was applied on the charge transport layer, and the coating solution was applied at 80 ° C. for 2 minutes.
After drying at 30 ° C. for 20 minutes, a protective layer having a thickness of 2 μm was formed to prepare a photoreceptor. The surface roughness of the outermost surface of the protective layer was an Rz value of 0.6.

For this photoreceptor, the contact angle to pure water was measured by a drop method using a contact angle meter CA-W type (manufactured by Kyowa Interface Science Co., Ltd.). The contact angle was 110 degrees. Further, the ratio of the surface elements of the separately prepared photoreceptor was measured by XPS, and as a result, F / C = 0.11.

The thus obtained electrophotographic photoreceptor, a charging roller as a charging means, a semiconductor laser having an oscillation wavelength of 405 nm as a light source as an image exposure means, and a beam system adjustable by an aperture, and a two-component developing means as a developing means. An isolated dot obtained by a 30 μm beam system is formed on a photoreceptor by an image forming experiment machine equipped with a unit and a pattern generator, and is transferred to an adhesive tape.
The images were read by a CCD camera and analyzed. The photosensitive member was charged at an initial charging potential of -600 V.
μm magnetic toner was used. The shape and reproducibility of the isolated dot were visually evaluated.

Further, the above-described electrophotographic photosensitive drum is shown in FIG.
(Except that the image exposure light source was an LD with emission at 405 nm (polygon
Image writing with a mirror)), image evaluation of the test chart was performed initially and after printing 10,000 sheets, and the occurrence of abnormal images and the like was observed. Table 9 shows the results.

(Example 2) In the same manner as in Example 1 except that an electron transporting material represented by the following structural formula (c) was used instead of the dibromoanthanethrone used in Example 1, a short film was formed on an aluminum cylinder. A wavelength light absorption layer, a charge generation layer, and a charge transport layer were formed.

[0131]

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Next, 3 parts of a charge transporting material represented by the following structural formula (d) and distearyl-3,3 ′ as an antioxidant
0.03 parts of thiodipropionate, 5 parts of a polystyrene resin (SBM-700, manufactured by Sanyo Chemical Industries, Ltd.), and titanium oxide fine particles (CR97, manufactured by Ishihara Sangyo Co., Ltd.) 2 as a filler
Layer, a protective layer coating solution consisting of 40 parts of THF and 140 parts of cyclohexanone was applied on the charge transport layer, and the thickness was about 2.5 parts.
A protective layer having a thickness of μm was formed to prepare a photosensitive drum. The surface roughness at the outermost surface of this protective layer was an Rz value of 0.8. The electrophotographic photosensitive member thus obtained was evaluated in the same manner as in Example 1.

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(Example 3) In the same manner as in Example 2 except that an electron transporting material represented by the following structural formula (e) was used instead of the electron transporting material used in Example 2, a short film was formed on an aluminum cylinder. A wavelength light absorption layer, a charge generation layer, and a charge transport layer were formed.

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Next, 3 parts of the charge transporting material represented by the above structural formula (f) and carbon fluoride particles (average primary particle diameter of 0.2 μm)
m) 2 parts, 5 parts of polycarbonate resin (Panlite TS-2050 manufactured by Teijin Limited), 2 parts of titanium oxide fine particles (CR97 manufactured by Ishihara Sangyo Co., Ltd.) as filler, 40 parts of THF, and 140 parts of cyclohexanone. Was applied onto the charge transport layer to form a protective layer having a thickness of about 1.5 μm, thereby producing a photosensitive drum.

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The contact angle of the photoreceptor with respect to pure water was measured by a drop method using a contact angle meter CA-W type (manufactured by Kyowa Interface Science Co., Ltd.). The contact angle was 113 degrees. The surface roughness at the outermost surface of this protective layer is Rz value of 0.
It was 7. In addition, for photoconductors created separately, XP
As a result of measuring the ratio of surface elements by S, F / C = 0.1
Met. The electrophotographic photosensitive member thus obtained was used in Example 1.
Was evaluated in the same way as

(Examples 4 to 6, Comparative Examples 1 to 4) Example 1
The photoreceptor was prepared and evaluated in the same manner except that the surface roughness of the aluminum plate support was changed as shown in Table 9 by changing the cutting conditions and performing mirror finishing. Table 9 shows the results.
Shown in

Comparative Examples 5 and 6 The photosensitive members of Examples 1 and 2 were mounted in the electrophotographic process shown in FIG. 2 and evaluated in the same manner except that a semiconductor laser having an oscillation wavelength of 780 nm was used as an image exposure light source. . Table 9 shows the results.

[Table 9]

Comparative Examples 7 and 8 Evaluations were made in the same manner as in Example 2 except that the average particle size of the toner used was changed. Table 10 shows the results.

[Table 10]

From these results, the electrophotographic photoreceptor and the electrophotographic apparatus of the present invention are excellent in dot reproducibility, can obtain a stable image even after repeated use, and can prevent generation of moire by the short wavelength light absorbing layer. It can be seen that it can be suppressed. A photoreceptor further provided with a protective layer containing a filler,
It is understood that by setting the surface to a low surface energy, a stable super-high-resolution image with excellent wear resistance can be obtained.

[0140]

As described above, according to the present invention, it is possible to form an image with minute dots with good reproducibility, and since it has excellent printing durability, it is possible to form an ultra-high resolution image such as 1200 dpi or 2400 dpi. It is possible to provide an electrophotographic photosensitive member, an electrophotographic apparatus, and a process cartridge which are highly durable and have a low frequency of component replacement and which can be charged with bipolarity.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a layer configuration of an example of an electrophotographic photosensitive member of the present invention.

FIG. 2 is a view for explaining the electrophotographic apparatus of the present invention.

FIG. 3 is a view for explaining another electrophotographic apparatus of the present invention.

FIG. 4 is a view for explaining a process cartridge of the present invention.

[Explanation of symbols]

 (In FIG. 1) 1 conductive support 2 short wavelength light absorbing layer 3 charge generating layer 4 charge transporting layer 5 protective layer

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme court ゛ (Reference) G03G 5/147 503 G03G 5/147 503 504 504 9/08 9/08 15/04 111 15/04 111 ( 72) Inventor Tomoyuki Shimada 1-3-6 Nakamagome, Ota-ku, Tokyo Inside Ricoh Company (72) Inventor Shinichi Kawamura 1-3-6 Nakamagome, Ota-ku, Tokyo F-term in Ricoh Company (Reference) 2H005 EA05 2H068 AA01 AA04 AA08 AA09 AA37 AA41 AA49 AA59 BB04 BB31 BB33 BB44 BB57 BB61 CA02 CA06 CA22 CA33 CA37 CA40 CA60 FA27 FB07 FB08 FC05 FC08 2H076 AB05 AB09 AB42

Claims (14)

[Claims] 1. An electrophotographic photosensitive member having a photosensitive layer on a conductive support, wherein a semiconductor laser or a light emitting diode having an oscillation wavelength in a range of 400 to 450 nm for a writing light source of an image exposing means of the electrophotographic photosensitive member. And a photosensitive layer on a conductive support via a short wavelength light absorbing layer,
An electrophotographic photoreceptor comprising a surface protective layer sequentially laminated. 2. The method according to claim 1, wherein the short-wavelength light-absorbing layer is at least 400-4.
Absorbs in the 50 nm writing light source wavelength range, and the surface roughness of the conductive support is 0.02 μm or more and 1.5 μm in Rz value.
Or less, the surface roughness of the short-wavelength light-absorbing layer is 0.02 μm or more and 1.5 μm or less in Rz value, and the surface roughness of the outermost surface of the photosensitive layer is 0.02 μm or more and 1.5 μm in Rz value.
2. The electrophotographic photosensitive member according to claim 1, wherein m is equal to or less than m. 3. The electrophotographic photoreceptor is composed of a laminated electrophotographic photoreceptor in which a charge generation layer, a charge transport layer and a surface protective layer are sequentially provided on a conductive support via a short wavelength light absorbing layer. The electrophotographic photoreceptor according to claim 1, wherein: 4. The electrophotographic photoreceptor according to claim 3, wherein the surface protective layer comprises at least a layer comprising a filler and a binder resin. 5. The electrophotographic photoreceptor according to claim 3, wherein the surface protective layer comprises at least a layer comprising a filler and a charge transport material. 6. The filler is titanium oxide, tin oxide, zinc oxide, zirconium oxide, indium oxide, silicon nitride, calcium oxide, barium sulfate, silica, colloidal silica, alumina, carbon black, fluororesin fine powder, polysiloxane-based filler. 6. The electrophotographic photosensitive member according to claim 4, wherein the photosensitive member is at least one selected from resin fine powder, polyethylene resin fine powder, and a graft copolymer having a core-shell structure. 7. The electrophotographic photoreceptor according to claim 3, wherein the surface protective layer comprises at least a layer made of a polymer type charge transport material. 8. The electrophotographic photoreceptor according to claim 3, wherein the surface protective layer comprises at least a layer made of a curable resin. 9. The electrophotographic photoreceptor according to claim 3, wherein the contact angle of the surface of the surface protective layer with pure water is 90 degrees or more. 10. The film thickness from the photosensitive layer to the surface protective layer is 4
4. The structure according to claim 3, wherein the thickness is not less than 15 μm.
An electrophotographic photoreceptor according to any one of claims 1 to 9. 11. An electrophotographic photosensitive member according to claim 1, and at least one unit selected from a charging unit, an image exposing unit, a developing unit, a transfer unit and a cleaning unit. A process cartridge formed and detachable from an electrophotographic apparatus main body. 12. An electrophotographic photoreceptor according to claim 1, and a charging means,
An electrophotographic apparatus comprising: an image exposure unit, a development unit, a transfer unit, and a cleaning unit using a semiconductor laser or a light emitting diode having an oscillation wavelength in a range of nm. 13. The beam diameter of a shorter one of the beam diameters of the writing light source in the main scanning direction and the sub scanning direction is 10 to 40.
13. The electrophotographic apparatus according to claim 12, wherein the diameter is μm. 14. An electrophotographic apparatus according to claim 12, wherein said developing means uses a toner having an average particle diameter of 4 to 8 μm.