JP5521519B2 - Electrophotographic photosensitive member, electrophotographic method using the same, electrophotographic apparatus and process cartridge - Google Patents

Description

  The present invention relates to an electrophotographic photosensitive member containing a specific charge transport material and a specific amine compound, an electrophotographic method using the electrophotographic photosensitive member, an electrophotographic apparatus, and an electrophotographic process cartridge.

  An electrophotographic photoreceptor (hereinafter sometimes referred to as “photoreceptor”) has a function of holding surface charges in the dark, a function of receiving light to generate charges, and a function of receiving light to transport charges. A so-called single-layer type photoreceptor that combines these functions in one layer, a layer that contributes mainly to charge generation, a surface charge in the dark, and a charge transport during photoreception. There is a so-called function-separated laminated type photoreceptor in which a function-separated layer is laminated on a layer to be separated.

  For example, a Carlson method is applied to image formation by electrophotography using these photoreceptors. Image formation by this method is performed by charging a photoconductor in a dark place by corona discharge, forming an electrostatic latent image such as text or a picture of an original on the surface of the charged photoconductor, The image is developed with toner, and the developed toner image is fixed on a support such as paper. After the toner image is transferred, the photoreceptor is subjected to charge removal, residual toner removal, light charge removal, etc., and then reused. To be served.

  In recent years, electrophotographic photoreceptors using organic substances have been put into practical use due to advantages such as flexibility, thermal stability, and film formability. Recently, a function-separated laminated type photoconductor comprising a charge generation layer containing a charge generation material and a charge transport layer containing a charge transport material as the photosensitive layer has become the mainstream, and in particular, an organic pigment is deposited as a charge generation material Many negatively charged photoreceptors have been proposed in which a layer or a layer dispersed in a resin is used as a charge generation layer, and an organic low molecular weight compound is used as a charge transport material and a layer dispersed in a resin is used as a charge transport layer.

Organic materials have many advantages not found in inorganic materials, but at the same time, organic materials that sufficiently satisfy all the characteristics required for electrophotographic photoreceptors have not been obtained.
That is, the image quality is deteriorated due to a decrease in charging potential, an increase in residual potential, a change in sensitivity, and the like due to repeated use. Although not all the causes of this deterioration have been elucidated, as one of the factors, oxidizing gases such as ozone and NOx released from the corona discharge charger, and oxidizing gases such as ozone and NOx in the atmosphere Has been found to cause significant damage to the photosensitive layer. In other words, these oxidizing gases cause various changes in properties by causing a chemical change with the material in the photoreceptor or by forming an adsorbate on the surface of the photosensitive layer. Causes increase in potential and decrease in resolution (image blur) due to decrease in surface resistance. As a result, the image quality is remarkably deteriorated and the life of the photoreceptor is shortened.
As a countermeasure against these problems, proposals have been made to prevent deterioration by adding an antioxidant or a stabilizer to the photosensitive layer. For example, as represented by Patent Document 1, many additions of hindered phenol-based antioxidants and hindered amine-based antioxidants have been proposed. In addition, Patent Documents 2 to 6 and the like can be given as examples of addition of amine derivatives. These proposals had a certain effect.

  In recent years, high wear resistance has been imparted by methods such as applying a lubricant to the surface of the photoconductor or providing a surface protective layer, and wear on the photoconductor has been suppressed by the process design around the photoconductor. Can be used for a long time. For this reason, it has become very important to improve the electrostatic characteristics of the photoconductor, but in order to maintain high image quality over a long period of time, the addition of conventional antioxidants and the like has become insufficient. .

  Recently, full-color and high-speed electrophotographic apparatuses are rapidly progressing, and accordingly, demand is diversified from a general office area to a SOHO area or a light printing area. In particular, in the light printing field, the printing volume is remarkably increased and the demand for image quality stability is increased. Therefore, it is indispensable to further increase the durability and stability of the organic photoreceptor.

  The problem of the exposure part potential fluctuation in the electrophotographic apparatus used in the light printing field is that the printing is started and one job is completed and the printing is finished rather than the exposure part potential fluctuation when printing is performed for a relatively long time. As a problem, the fluctuation in the potential of the exposed portion when the process is resumed is larger. Hereinafter, the former is referred to as daily fluctuation of the exposure part potential, and the latter is referred to as intra-job fluctuation of the exposure part potential. In the case of daily fluctuations in the exposure part potential, the effect is not noticeable and the potential can be corrected in the apparatus. Therefore, the problem is not so great, but if the fluctuation in the job is large, the influence is conspicuous. If the potential fluctuates by several tens or several sheets in the job, it becomes difficult to correct the potential, which is a serious problem.

  In particular, in the light printing field, there is a demand for printing a large amount of the same image pattern with one job. In this case, if the fluctuation in the exposure portion potential in the job is large, the image density changes and the image quality consistency is lowered. become. If it is a character-based image pattern, it will not stand out so much, but if it is an image-based and full-color image pattern, not only the image density but also the color will change, leading to a very serious problem. That is, it is required to reduce the exposed portion potential of the photosensitive member and further suppress the exposed portion potential fluctuation in long-term repetitive printing, not only the daily fluctuation but also the intra-job fluctuation.

  The object of the present invention has high durability even for repeated use over a long period of time, and suppresses image deterioration due to image density reduction or image blurring. An object of the present invention is to provide an electrophotographic photosensitive member that suppresses fluctuations in the job and can stably obtain a high-quality image. It is an object of the present invention to provide a highly durable and highly stable electrophotographic method, an electrophotographic apparatus, and a process cartridge for an electrophotographic apparatus, in which the image density is always stable and the image quality is consistent by using these photoconductors.

  As a result of intensive studies to solve the above problems, the electrophotographic photoreceptor according to the present invention described in the following [1] to [9], an electrophotographic method using the electrophotographic photoreceptor, an electrophotographic apparatus, and The present inventors have found that the above problems can be solved by a process cartridge for an electrophotographic apparatus, and have reached the present invention. Hereinafter, the present invention will be specifically described.

  [1]: The above problem is that in an electrophotographic photosensitive member having a photosensitive layer on a conductive support, the photosensitive layer is expressed by the following general formula (1) and the following general formula (2). It is solved by an electrophotographic photoreceptor characterized by containing an amine compound represented.

[In Formula (1), A < ₁ >, A < ₂ > may have either the alkyl group which may have a phenyl group, or a methyl group, an ethyl group, t-butyl group, a methoxy group, and an ethoxy group. Represents an aryl group, which may be the same or different. Ar represents a condensed polycyclic aromatic hydrocarbon group which may have either a methyl group or a t-butyl group. ]

[In formula (2), A and B are each selected from the groups represented by the following formula (i) or (ii), and may be the same or different.
(I) _-CH 2 X
_(Ii) -CH 2 _CH 2 Y
[However, in the formula (i) or (ii), X and Y each represents an aromatic residue, a cycloalkyl group or a heterocycloalkyl group, and these may have a substituent. ]]

[2]: The above problem is a charging step for charging the surface of the electrophotographic photosensitive member according to claim 1;
An image exposure step of forming an electrostatic latent image on the electrophotographic photoreceptor;
A developing step of developing the electrostatic latent image to form a toner image;
This is solved by an electrophotographic method in which the toner image is transferred directly to a recording material or a transfer step of transferring the toner image to a recording material via an intermediate transfer member.

[3]: In the electrophotographic method according to the above [2], the electrophotographic method is a digital method,
In the image exposure step, an electrostatic latent image is formed on the electrophotographic photosensitive member by light irradiation using a semiconductor laser (LD) or a light emitting diode (LED) as a light source.

[4]: The above-described problem is obtained by the electrophotographic photosensitive member according to claim 1;
Charging means for charging the surface of the electrophotographic photosensitive member;
Image exposure means for forming an electrostatic latent image on the surface of the electrophotographic photosensitive member;
Developing means for developing the electrostatic latent image to form a toner image;
Transfer means for directly transferring the toner image to a recording material or transferring it to an intermediate transfer member;
The present invention is solved by an electrophotographic apparatus.

[5]: In the electrophotographic apparatus according to the above [4], the electrophotographic apparatus is a digital system,
The image exposure means uses a semiconductor laser (LD) or a light emitting diode (LED) that forms an electrostatic latent image on the surface of the electrophotographic photosensitive member as a light source.

  [6]: In the electrophotographic apparatus according to the above [4] or [5], a tandem type including a plurality of image forming elements each including at least the electrophotographic photosensitive member, the charging unit, the developing unit, and the transfer unit. It is characterized by having the configuration of

[7] The electrophotographic apparatus according to any one of claims 4 to 6, further comprising an intermediate transfer unit in addition to the transfer unit that transfers to the intermediate transfer member,
The toner image formed on the electrophotographic photoreceptor is primarily transferred to the intermediate transfer member by the transfer unit to form an image on the intermediate transfer member, and the image on the intermediate transfer member is formed by the intermediate transfer unit. Is secondarily transferred onto the recording material.

[8] In the electrophotographic apparatus according to [7], the image that is secondarily transferred onto the recording material is a color image composed of a plurality of colors of toner,
The transfer unit forms an image on the intermediate transfer member by sequentially superimposing toner of each color on the intermediate transfer member, and the intermediate transfer unit collects the images on the intermediate transfer member on the recording material. And secondary transfer.

[9]: The problem described above is the electrophotographic photosensitive member according to [1],
Charging means for charging the surface of the electrophotographic photosensitive member; image exposing means for forming an electrostatic latent image on the surface of the electrophotographic photosensitive member; developing means for developing the electrostatic latent image to form a toner image; And at least one selected from a cleaning unit that cleans the surface of the photosensitive member and a transfer unit that directly transfers the toner image to a recording material or transfers it to an intermediate transfer member. Solved by process cartridge.

According to the electrophotographic photosensitive member of the present invention, the charge transport material contains the charge transport material represented by the general formula (1) and the amine compound represented by the general formula (2) in the photosensitive layer. The deterioration of the charge transport material is suppressed without deteriorating the function, and the characteristics of the photoreceptor are stabilized even after repeated use over a long period of time (for example, the electrostatic characteristics are stabilized and the exposure portion potential and the residual potential are increased). Furthermore, fluctuations in the job are also suppressed, and a high-quality image can be obtained stably over a long period of time.
In addition, by using the electrophotographic photosensitive member of the present invention, an electrophotographic method, an electrophotographic apparatus, and a process for an electrophotographic apparatus that can output an image with little change in image density and color, that is, excellent image quality consistency. A cartridge is provided.

FIG. 2 is a cross-sectional view illustrating a configuration example of an electrophotographic photosensitive member according to the present invention. It is sectional drawing which shows another structural example of the electrophotographic photoreceptor which concerns on this invention. It is sectional drawing which shows another example of a structure of the electrophotographic photoreceptor which concerns on this invention. It is sectional drawing which shows another example of a structure of the electrophotographic photoreceptor which concerns on this invention. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic diagram illustrating an electrophotographic apparatus and an electrophotographic method according to the present invention and a configuration of an electrophotographic apparatus according to a first embodiment. It is the schematic which shows the structure in 2nd Embodiment of the electrophotographic apparatus which concerns on this invention. It is the schematic which shows the structure in 3rd Embodiment of the electrophotographic apparatus which concerns on this invention. It is the schematic which shows the structure in 4th Embodiment of the electrophotographic apparatus which concerns on this invention. It is the schematic which shows the structure in one Embodiment of the process cartridge which concerns on this invention. It is a powder XD spectrum of the titanyl phthalocyanine used for the charge generation layer coating liquid of Examples 18-22.

  As described above, the electrophotographic photosensitive member of the present invention is an electrophotographic photosensitive member having a photosensitive layer on a conductive support, wherein the photosensitive layer is represented by the following general formula (1), It contains an amine compound represented by the formula (2).

[In Formula (1), A < ₁ >, A < ₂ > may have either the alkyl group which may have a phenyl group, or a methyl group, an ethyl group, t-butyl group, a methoxy group, and an ethoxy group. Represents an aryl group, which may be the same or different. Ar represents a condensed polycyclic aromatic hydrocarbon group which may have either a methyl group or a t-butyl group. ]

[In formula (2), A and B are each selected from the groups represented by the following formula (i) or (ii), and may be the same or different.
(I) _-CH 2 X
_(Ii) -CH 2 _CH 2 Y
[However, in the formula (i) or (ii), X and Y each represents an aromatic residue, a cycloalkyl group or a heterocycloalkyl group, and these may have a substituent. ]]

Hereinafter, the configuration of the electrophotographic photosensitive member of the present invention will be described with reference to the drawings.
FIG. 1 is a cross-sectional view showing a configuration example of an electrophotographic photosensitive member according to the present invention. A photosensitive layer 33 mainly composed of a charge generating material and a charge transporting material is provided on a conductive support 31. .
FIG. 2 is a cross-sectional view showing another configuration example of the electrophotographic photosensitive member according to the present invention. A charge generation layer 35 mainly composed of a charge generation material and a charge transport material are provided on a conductive support 31. The charge transport layer 37 as a main component has a laminated structure.
FIG. 3 is a sectional view showing still another structural example of the electrophotographic photosensitive member according to the present invention. A photosensitive layer 33 mainly composed of a charge generating material and a charge transporting material is provided on a conductive support 31. Further, a protective layer 39 is provided on the surface of the photosensitive layer. In this case, the protective layer 39 may contain an amine compound represented by the general formula (2).
FIG. 4 is a cross-sectional view showing still another structural example of the electrophotographic photosensitive member according to the present invention. A charge generation layer 35 mainly composed of a charge generation material and a charge transport material are provided on a conductive support 31. A charge transport layer 37 as a main component is laminated, and a protective layer 39 is further provided on the charge transport layer. In this case, the protective layer 39 may contain the amine compound of the general formula (2).

Examples of the conductive support 31 include those having a volume resistance of 10 ¹⁰ Ω · cm or less, for example, metals such as aluminum, nickel, chromium, nichrome, copper, gold, silver, platinum, tin oxide, indium oxide, etc. The metal oxide of the above is coated with film or cylindrical plastic or paper by vapor deposition or sputtering, or a plate made of aluminum, aluminum alloy, nickel, stainless steel or the like and extruded by drawing or drawing. After pipe formation, surface treatment pipes such as cutting, superfinishing, and polishing can be used. An endless nickel belt or an endless stainless steel belt can also be used as the conductive support 31.

In addition, a material obtained by dispersing conductive powder in an appropriate binder resin and coating it on the support can also be used as the conductive support 31 of the present invention. Examples of the conductive powder include carbon black, acetylene black, metal powder such as aluminum, nickel, iron, nichrome, copper, zinc, and silver, or metal oxide powder such as conductive tin oxide and ITO. It is done. The binder resin used at the same time is polystyrene, styrene-acrylonitrile copolymer, styrene-butadiene copolymer, styrene-maleic anhydride copolymer, polyester, polyvinyl chloride, vinyl chloride-vinyl acetate copolymer. , Polyvinyl acetate, polyvinylidene chloride, polyarylate resin, phenoxy resin, polycarbonate, cellulose acetate resin, ethyl cellulose resin, polyvinyl butyral, polyvinyl formal, polyvinyl toluene, poly-N-vinylcarbazole, acrylic resin, silicone resin, epoxy resin, Thermoplastic, thermosetting resin or photo-curing resin such as melamine resin, urethane resin, phenol resin, alkyd resin and the like can be mentioned. Such a conductive layer can be provided by dispersing and coating these conductive powder and binder resin in a suitable solvent such as tetrahydrofuran, dichloromethane, methyl ethyl ketone, and toluene.
Furthermore, it is electrically conductive by a heat-shrinkable tube in which the conductive powder is contained in a material such as polyvinyl chloride, polypropylene, polyester, polystyrene, polyvinylidene chloride, polyethylene, chlorinated rubber, Teflon (registered trademark) on a suitable cylindrical substrate. Those provided with a conductive layer can also be used favorably as the conductive support 31 of the present invention.

Next, the photosensitive layer will be described. The photosensitive layer may be a single layer photosensitive layer (FIGS. 1 and 3) including a charge generation material and a charge transport material, or may be a laminated type (FIGS. 2 and 4) including a charge generation layer and a charge transport layer. However, for convenience of explanation, the photosensitive layer having a laminated structure will be described first.
The charge generation layer 35 is a layer mainly composed of a charge generation material. A known charge generation material can be used for the charge generation layer 35, and representative examples thereof include monoazo pigments, disazo pigments, trisazo pigments, perylene pigments, perinone pigments, quinacridone pigments, and quinone condensed polycycles. Examples thereof include compounds, squaric acid dyes, other phthalocyanine pigments, naphthalocyanine pigments, and azulenium salt dyes. These charge generation materials may be used alone or in combination of two or more.

The charge generation layer 35 is obtained by dispersing a charge generation material in a suitable solvent together with a binder resin as necessary using a ball mill, an attritor, a sand mill, an ultrasonic wave, or the like to form a coating solution. It is formed by applying to and drying.
The binder resin used as necessary includes polyamide, polyurethane, epoxy resin, polyketone, polycarbonate, silicone resin, acrylic resin, polyvinyl butyral, polyvinyl formal, polyvinyl ketone, polystyrene, polysulfone, poly-N-vinylcarbazole, poly Examples include acrylamide, polyvinyl benzal, polyester, phenoxy resin, vinyl chloride-vinyl acetate copolymer, polyvinyl acetate, polyphenylene oxide, polyamide, polyvinyl pyridine, cellulosic resin, casein, polyvinyl alcohol, and polyvinyl pyrrolidone. The amount of the binder resin is suitably 0 to 500 parts by weight, preferably 10 to 300 parts by weight with respect to 100 parts by weight of the charge generating material. The binder resin may be added before or after dispersion.

  Examples of the solvent include isopropanol, acetone, methyl ethyl ketone, cyclohexanone, tetrahydrofuran, dioxane, ethyl cellosolve, ethyl acetate, methyl acetate, dichloromethane, dichloroethane, monochlorobenzene, cyclohexane, toluene, xylene, ligroin, etc. Solvents, ester solvents, and ether solvents are preferably used. These may be used alone or in combination of two or more.

The charge generation layer 35 includes a charge generation material, a solvent, and a binder resin as main components, but may contain various additives such as a sensitizer, a dispersant, a surfactant, and silicone oil.
As a coating method for the coating solution, a dip coating method, spray coating, beat coating, nozzle coating, spinner coating, ring coating, or the like can be used.
The thickness of the charge generation layer 35 is suitably about 0.01 to 5 μm, preferably 0.1 to 2 μm.

  The charge transport layer 37 is a layer mainly composed of a charge transport material, and in the present invention, the charge transport material represented by the general formula (1) and the amine compound represented by the general formula (2) are used. contains.

As described above, in the charge transport material, A ₁ and A ₂ in the general formula (1) are alkyl groups (for example, a methyl group, an ethyl group, and the like) that may have a substituent (for example, a phenyl group). Or an aryl group (for example, phenyl group, biphenyl group, naphthyl group, pyrenyl group, etc.) that may have a substituent (for example, methyl group, ethyl group, t-butyl group, methoxy group, ethoxy group, etc.) These may be the same or different. Ar is a condensed polycyclic aromatic hydrocarbon group (for example, naphthyl group, acenaphthyl group, anthryl group, phenanthryl group, pyrenyl group, chrysenyl group) which may have a substituent (for example, methyl group, t-butyl group, etc.) , Fluoranthyl group, etc.). Preferred examples of the charge transport material represented by the general formula (1) are listed in Tables 1 to 6 below. However, the present invention is not limited to these compounds.
In Table 2, Compound No. Reference numeral 13 is a reference example in which Ar is not a condensed polycyclic aromatic hydrocarbon group and is not included in the charge transport material represented by the general formula (1).

In the amine compound, A and B in the general formula (2) are each selected from groups represented by the following formula (i) or (ii) and may be the same or different.
(I) _-CH 2 X
_(Ii) -CH 2 _CH 2 Y
[However, in the formula (i) or (ii), X and Y each represents an aromatic residue, a cycloalkyl group or a heterocycloalkyl group, and these may have a substituent. ]
Here, as the aromatic residue, for example, phenyl group, naphthyl group, anthryl group, etc., as the cycloalkyl group, for example, cyclopentyl group, cyclohexyl group, etc., as the heterocycloalkyl group, for example, A tetrahydropyranyl group, and the like.
Preferred examples of the amine compound represented by the general formula (2) are shown in the following structural formulas (2a) to (2e). However, the present invention is not limited to these compounds.

In the present invention, by combining the charge transport material represented by the general formula (1) and the amine compound represented by the general formula (2), the electrostatic characteristics are stable even in long-term repeated use, Furthermore, fluctuations within the job can also be reduced.
Although these causes are not clear, one reason is that the amine compound represented by the general formula (2) has excellent gas resistance. This is presumably because the amine compound represented by the general formula (2) has a strong basic amino group, which can prevent the charge transport material from being altered by the oxidizing gas. In addition, unlike antioxidants, they do not have polar groups that easily trap charges, and they themselves have charge transport properties, so even if they are added in relatively large amounts, they have the effect of increasing the exposed area potential and residual potential. Is estimated to be reduced.
In addition, the amine compound represented by the general formula (2) is speculated to have a specific influence on the charge transport function with respect to the charge transport material represented by the general formula (1). . That is, due to the excellent gas resistance of the amine compound represented by the general formula (2), the deterioration of the charge transport material due to the oxidizing gas such as ozone and NOx generated by a corona charger in the apparatus is suppressed, Furthermore, since the influence on the charge transport function is small, the electrostatic characteristics can be stabilized even after repeated use, and fluctuations in the job can be reduced.

  The charge transport layer 37 comprises a charge transport material represented by the general formula (1) and an amine compound represented by the general formula (2) together with a binder resin, if necessary, in a suitable solvent in a ball mill, an atom. It is formed by dispersing using a lighter, sand mill, ultrasonic wave, or the like to form a coating solution, which is coated on the charge generation layer 35 and dried.

  The content of the charge transport material represented by the general formula (1) in the charge transport layer 37 is preferably 30 to 200 parts by weight with respect to 100 parts by weight of the binder resin. When the content of the charge transport material represented by the general formula (I) is less than 30 parts by weight, the electrical characteristics are deteriorated such that the residual potential is increased. On the other hand, when the amount is more than 200 parts by weight, mechanical properties such as wear resistance are deteriorated.

  Furthermore, the charge transport material represented by the general formula (1) and other charge transport materials can be mixed and used. In this case, the content ratio of the charge transport material represented by the general formula (1) and the other charge transport material is [charge transport material represented by the general formula (I)]: [other charge transport material] = The range of 50:50 to 95: 5 is preferable, and the range of 70:30 to 95: 5 is more preferable.

Examples of the other charge transport materials include the following.
Charge transport materials include electron transport materials and hole transport materials.
Examples of the electron transport material include chloroanil, bromanyl, tetracyanoethylene, tetracyanoquinodimethane, 2,4,7-trinitro-9-fluorenone, 2,4,5,7-tetranitro-9-fluorenone, 2, 4,5,7-tetranitroxanthone, 2,4,8-trinitrothioxanthone, 2,6,8-trinitro-4H-indeno [1,2-b] thiophen-4-one, 1,3,7- Examples thereof include electron-accepting substances such as trinitrodibenzothiophene-5,5-dioxide and benzoquinone derivatives.
Examples of the hole transport material include poly-N-vinylcarbazole and derivatives thereof, poly-γ-carbazolylethyl glutamate and derivatives thereof, pyrene-formaldehyde condensates and derivatives thereof, polyvinylpyrene, polyvinylphenanthrene, polysilane, and oxazole. Derivatives, oxadiazole derivatives, imidazole derivatives, monoarylamine derivatives, diarylamine derivatives, triarylamine derivatives, stilbene derivatives, α-phenylstilbene derivatives, benzidine derivatives, diarylmethane derivatives, triarylmethane derivatives, 9-styrylanthracene derivatives , Pyrazoline derivatives, divinylbenzene derivatives, hydrazone derivatives, indene derivatives, butadiene derivatives, pyrene derivatives, bisstilbene derivatives, enamine derivatives, etc. And other known materials.
These charge transport materials may be used alone or in combination of two or more.

  The content of the amine compound represented by the general formula (2) in the charge transport layer 37 is preferably 1 to 30 parts by weight with respect to 100 parts by weight of the charge transport material. When the content of the amine compound is less than 1 part by weight, the decrease in charging due to the influence of ozone and NOx and the blurring of the image are remarkable. On the other hand, when the content is more than 30 parts by weight, the increase in residual potential due to repeated use increases. .

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

  The film thickness of the charge transport layer is preferably 50 μm or less, and preferably 25 μm or less from the viewpoint of resolution and responsiveness. The lower limit varies depending on the system to be used (particularly charging potential), but is preferably 5 μm or more.

  As the solvent of the coating solution used for forming the charge transport layer 37, tetrahydrofuran, dioxane, toluene, dichloromethane, monochlorobenzene, dichloroethane, cyclohexanone, methyl ethyl ketone, acetone, or the like is used. These may be used alone or in combination of two or more. As a coating method of the coating solution, a conventional coating method such as dip coating, spray coating, beat coating, nozzle coating, spinner coating, ring coating, or the like can be used.

Next, the case where the photosensitive layer has a single layer structure (in the case of FIGS. 1 and 3) will be described.
The photosensitive layer 33 can be formed by dissolving or dispersing a charge generating substance, a charge transporting substance, and a binder resin in an appropriate solvent to form a coating solution, which is coated and dried. The photosensitive layer 33 contains the charge transport material represented by the general formula (1) and the amine compound represented by the general formula (2). Moreover, a plasticizer, a leveling agent, antioxidant, etc. can also be added as needed.

  Also in the single-layer type photosensitive layer 33, the materials (charge generating material, charge transporting material, binder resin) used for the above-mentioned laminated photosensitive layer (charge generating layer, charge transporting layer) can be similarly used. . In the case of the photosensitive layer 33 having a single layer structure, it is preferable to use the above-described electron transporting material in combination as a charge transporting material for high sensitivity.

In the photosensitive layer 33 having a single layer structure, the charge generation material is suitably 0.1 to 30% by weight, preferably 0.5 to 5% by weight, based on the entire photosensitive layer. When the concentration of the charge generating substance is low, the photoreceptor sensitivity tends to decrease, and when the concentration is high, the chargeability and the film strength tend to decrease.
The content of the charge transport material represented by the general formula (1) is preferably 30 to 200 parts by weight with respect to 100 parts by weight of the binder resin. In addition, the content of the electron transport material is preferably 30 to 200 parts by weight with respect to 100 parts by weight of the binder resin.
Moreover, it is preferable that content of the amine compound represented by the said General formula (2) shall be 1-30 weight part with respect to 100 weight part of charge transport substances.

  The film thickness of the photosensitive layer is preferably 50 μm or less, and preferably 25 μm or less from the viewpoint of resolution and responsiveness. The lower limit varies depending on the system to be used (particularly charging potential), but is preferably 5 μm or more.

  In the photoreceptor of the present invention, an undercoat layer (not shown) can be provided between the conductive support 31 and the photosensitive layer. In general, the undercoat layer is mainly composed of a resin. However, considering that the photosensitive layer is coated with a solvent on these resins, it is desirable that the resin be a resin having a high solvent resistance with respect to a general organic solvent. . Examples of such resins include water-soluble resins such as polyvinyl alcohol, casein, and sodium polyacrylate, alcohol-soluble resins such as copolymer nylon and methoxymethylated nylon, polyurethane, melamine resin, phenol resin, alkyd-melamine resin, and epoxy. Examples thereof include a curable resin that forms a three-dimensional network structure such as a resin. Further, fine powder pigments of metal oxides such as titanium oxide, silica, alumina, zirconium oxide, tin oxide, and indium oxide may be added to the undercoat layer in order to prevent moire and reduce residual potential.

These undercoat layers can be formed using an appropriate solvent and a coating method like the above-mentioned photosensitive layer. Also, as the undercoat layer of the present invention, a silane coupling agent, a titanium coupling agent, a chromium coupling agent, or the like can be used, or Al ₂ O ₃ provided by anodization, polyparaxylylene (parylene) ) And other organic substances such as SiO ₂ , SnO ₂ , TiO ₂ , ITO, and CeO ₂ provided by a vacuum thin film forming method can also be used favorably. Further, other known ones can also be used. The thickness of the undercoat layer is suitably from 0 to 5 μm.

In the photoreceptor of the present invention, the protective layer 39 may be provided on the photosensitive layer for the purpose of protecting the photosensitive layer.
Materials used for the protective layer 39 include ABS resin, ACS resin, olefin-vinyl monomer copolymer, chlorinated polyether, aryl resin, phenol resin, polyacetal, polyamide, polyamideimide, polyacrylate, polyallylsulfone, Polybutylene, polybutylene terephthalate, polycarbonate, polyethersulfone, polyethylene, polyethylene terephthalate, polyimide, acrylic resin, polymethylbenten, polypropylene, polyphenylene oxide, polysulfone, polystyrene, polyarylate, AS resin, butadiene-styrene copolymer, polyurethane, Examples thereof include resins such as polyvinyl chloride, polyvinylidene chloride and epoxy resin. From the viewpoint of filler dispersibility, residual potential, and coating film defects, polycarbonate or polyarylate is particularly effective and useful.
A filler material can be added to the protective layer of the photoreceptor for the purpose of improving the wear resistance. As the solvent used, all solvents used in the charge transport layer 37 such as tetrahydrofuran, dioxane, toluene, dichloromethane, monochlorobenzene, dichloroethane, cyclohexanone, methyl ethyl ketone, and acetone can be used. However, a solvent having a high viscosity is preferable at the time of dispersion, but a solvent having high volatility is preferable at the time of coating. When there is no solvent satisfying these conditions, it is possible to use a mixture of two or more solvents having respective physical properties, which may have a great effect on filler dispersibility and residual potential. .

Moreover, the amine compound represented by the said General formula (2) may be contained in the protective layer. Further, the addition of the charge transport material mentioned in the charge transport layer 37 is effective and useful for reducing the residual potential and improving the image quality.
As a method for forming the protective layer, conventional methods such as dip coating, spray coating, beat coating, nozzle coating, spinner coating, ring coating, etc. can be used. preferable.

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

In the present invention, in order to improve environmental resistance, in order to prevent a decrease in sensitivity and an increase in residual potential, oxidation is performed on each layer such as a charge generation layer, a charge transport layer, an undercoat layer, a protective layer and an intermediate layer. Inhibitors, plasticizers, lubricants, UV absorbers and leveling agents can be added. Examples of typical compounds of these materials are described below.
Examples of the antioxidant that can be added to each layer include phenolic compounds, paraphenylenediamines, hydroquinones, organic sulfur compounds, and organic phosphorus compounds.
Examples of plasticizers that can be added to each layer include phosphate ester plasticizers, phthalate ester plasticizers, aromatic carboxylic ester plasticizers, aliphatic dibasic ester plasticizers, fatty acid ester derivatives, and oxyacid esters. Examples include plasticizers, epoxy plasticizers, dihydric alcohol ester plasticizers, chlorine-containing plasticizers, polyester plasticizers, sulfonic acid derivatives, and citric acid derivatives.
Examples of the lubricant that can be added to each layer include hydrocarbon compounds, fatty acid compounds, fatty acid amide compounds, ester compounds, alcohol compounds, metal soaps, natural waxes, silicone compounds, and fluorine compounds.
Examples of ultraviolet absorbers that can be added to each layer include benzophenone compounds, salicylate compounds, benzotriazole compounds, cyanoacrylate compounds, quenchers (metal complex salts), and HALS (hindered amines).

[Electrophotographic apparatus, electrophotographic method]
As described above, the electrophotographic method of the present invention comprises a charging step for charging the surface of the electrophotographic photosensitive member of the present invention, an image exposing step for forming an electrostatic latent image on the electrophotographic photosensitive member, and the electrostatic A development step of developing a latent image to form a toner image and a transfer step of transferring the toner image directly to a recording material or transferring the toner image to a recording material via an intermediate transfer member are repeated. Is.
Further, the electrophotographic apparatus of the present invention comprises the electrophotographic photosensitive member of the present invention, a charging unit for charging the surface of the electrophotographic photosensitive member, and an image exposing unit for forming an electrostatic latent image on the surface of the electrophotographic photosensitive member. And developing means for developing the electrostatic latent image to form a toner image, and transfer means for transferring the toner image directly to a recording material or transferring it to an intermediate transfer member. In addition, other means appropriately selected as necessary are provided. Examples of other means include cleaning means, static elimination means, recycling means, and control means.
Hereinafter, the electrophotographic apparatus and the electrophotographic method according to the present invention will be described in detail with specific examples with reference to the drawings.

<First Embodiment>
FIG. 5 is a schematic diagram for explaining the electrophotographic apparatus and the electrophotographic method according to the present invention, and is a schematic diagram showing the configuration of the electrophotographic apparatus according to the first embodiment of the present invention.
In FIG. 5, a photoreceptor 1 is the above-described electrophotographic photoreceptor according to the present invention. The photosensitive member 1 has a drum shape, but may be a sheet shape or an endless belt shape.
In the embodiment shown in FIG. 5, the drum-shaped photoreceptor 1 is rotated counterclockwise in the figure by a driving means (not shown), and an image is formed by an electrophotographic method by each means provided around the photoreceptor 1. The Hereinafter, description will be given in the order of each step of the electrophotographic method.

(Charging means, charging process)
First, the surface of the photoreceptor 1 is uniformly charged by a charging charger 3 as a charging unit. The charging charger 3 may be appropriately selected from conventionally known ones according to the characteristics of the electrophotographic photosensitive member (photosensitive member) 1 and the developing toner, and the surface of the photosensitive member 1 has a predetermined polarity (positive charging or negative charging). Any one can be applied as long as it is charged to a predetermined potential. Examples of the charging charger 3 include a corotron, a scorotron, a solid state charger (solid state charger), a charging roller, and the like.

(Image exposure means, image exposure process)
Next, an electrostatic latent image is formed on the surface of the uniformly charged photoreceptor 1 by an image exposure unit 5 as an image exposure unit. As the image exposure unit 5, for example, fluorescent materials such as fluorescent lamps, tungsten lamps, halogen lamps, mercury lamps, sodium lamps, light emitting diodes (LEDs), semiconductor lasers (LD), and electroluminescence (EL) can be used. It is preferable to use a light emitting diode or a semiconductor laser. In order to irradiate only light in a desired wavelength range during image exposure, 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 are used. It can be disposed between the photoreceptor 1 and the image exposure unit 5.

(Development means, development process)
The electrostatic latent image formed on the surface of the photoreceptor 1 is developed by a developing unit 6 as developing means using toner. That is, the electrostatic latent image is developed by the developing unit 6 to form a visible toner image. The developing unit 6 may be appropriately selected from conventionally known developing units according to the toner to be used. Examples of the developing unit 6 include a one-component developing method and a two-component developing method, and further, there are ones for magnetic toner and non-magnetic toner, respectively.

(Transfer means, transfer process)
Further, the toner image carried on the photoreceptor 1 is conveyed to a transfer charger 10 as a transfer unit as the photoreceptor 1 rotates. As the transfer charger 10, the same one as the above-described charging charger 3 can be applied, but a combination of the transfer charger 10 and the separation charger 11 as shown in FIG. 5 is effective. Further, in order to improve the transfer efficiency, it is preferable to provide a pre-transfer charger 7 upstream of the transfer charger 10 (relative to the rotation direction of the photosensitive member 1) and precharge the toner image. As the pre-transfer charger 7, the same one as the above-described charging charger 3 can be applied.
On the other hand, at a position where the photoreceptor 1 and the transfer charger 10 face each other, a transfer paper 9 as a recording material is conveyed by a registration roller 8 or the like so that a toner image is transferred to a desired position on the transfer paper 9. The
The toner image is transferred to the transfer paper 9 by the transfer charger 10 at a position where the toner image on the photoreceptor 1 and the transfer paper 9 face each other.
The transfer paper 9 onto which the toner image has been transferred reaches the separation claw 12 by rotating with the photosensitive member 1 and is separated from the surface of the photosensitive member 1 by the separation claw 12, and further description is omitted. Then, it is discharged out of the electrophotographic apparatus through a fixing process.

(Cleaning means, cleaning process)
Here, on the surface of the photosensitive member 1 after transfer by the transfer charger 10 and separation of the transfer paper 9 by the separation claw 12, toner images that could not be transferred onto the transfer paper 9, so-called transfer residual toner, paper dust, etc. There are deposits. For this reason, deposits are removed from the surface of the photoreceptor 1 by the fur brush 14 and the cleaning blade 15 which are cleaning means. As the cleaning means, in addition to the fur brush 14 and the cleaning blade 15, conventionally known ones such as a mag fur brush can be used. Further, only the fur brush or only the cleaning blade can be used. In order to improve the cleaning efficiency, it is preferable to precharge by the pre-cleaning charger 13 before using the cleaning means. As the pre-cleaning charger 13, the same one as the above-described charging charger 3 can be applied.

(Static elimination means, static elimination process)
The photosensitive member 1 from which the deposits have been removed from the surface by the cleaning means is further discharged by irradiating light from the charge removing lamp 2 as a charge removing means, thereby completing a series of image forming processes by the electrophotographic method. By repeating this series of electrophotographic image forming processes, it is possible to form images on a plurality of recording materials.
Conventionally known means can be used as the charge eliminating means. For example, the charge removing lamp 2 can be the same as the image exposure unit 5 described above.

In the image forming process by the series of electrophotographic methods described above, when the electrophotographic photosensitive member (photosensitive member) 1 is positively (negatively) charged and image exposure is performed, the surface of the photosensitive member 1 is positive (negative). An electrostatic latent image is formed. A positive image can be obtained by developing this with negative (positive) toner (electrodetection fine particles), and a negative image can be obtained by developing with positive (negative) toner. The charging polarity of the electrophotographic photosensitive member (photosensitive member) 1 and the polarity of the toner used for development are arbitrary and may be any one.
Further, the various light sources used in the image exposure unit 5 are not limited to being used in the form shown in FIG. 5, and other than that, a transfer process, a static elimination process, a cleaning process, or a previous process using light irradiation together. It can be used for processes such as exposure.

<Second Embodiment>
FIG. 6 is a schematic diagram showing the configuration of the electrophotographic apparatus according to the second embodiment of the present invention.
The photosensitive member 21 has at least a photosensitive layer (not shown), is driven by driving rollers 22a and 22b, is charged by a charger 23 as charging means, and is exposed and developed by a light source 24 as image exposure means. Development (not shown), transfer using a transfer charger 25 as a transfer means, exposure before cleaning with a light source 26, cleaning with a cleaning brush 27 as a cleaning means, and static elimination with a light source 28 as a static elimination means are repeated. In FIG. 6, the photoconductor 21 (of course, the support is translucent in this case) is irradiated with pre-cleaning exposure light from the conductive support (not shown) side.

The image forming process by the electrophotographic method performed using the electrophotographic apparatus shown in FIG. 6 exemplifies the embodiment in the present invention, and it goes without saying that other embodiments are possible. For example, in FIG. 6, the pre-cleaning exposure is performed from the conductive support (not displayed) side, but this may be performed from the photosensitive layer (not displayed) side. Irradiation may be performed from the conductive support side.
On the other hand, as the process of irradiating light, image exposure, pre-cleaning exposure, and static elimination exposure are illustrated, but in addition, there are provided pre-transfer exposure, pre-exposure of image exposure, and other known light irradiation processes. Thus, the photosensitive member 21 can be irradiated with light.

<Third Embodiment>
Furthermore, an embodiment of an electrophotographic printer (hereinafter simply referred to as a printer) will be described as a full-color electrophotographic apparatus to which the present invention is applied.
FIG. 7 is a schematic view showing the configuration of the electrophotographic apparatus according to the third embodiment of the present invention.
In FIG. 7, a drum-shaped photosensitive member (photosensitive drum) 56 which is a latent image carrier is rotated counterclockwise in the figure, and the surface thereof is a charging charger 53 which is a charging means using a corotron or a scorotron. Then, the electrostatic latent image is carried by scanning with exposure (laser light) L emitted from a laser optical device which is an image exposure means (not shown). Since this scanning is performed based on single-color image information obtained by decomposing a full-color image into yellow, magenta, cyan, and black color information, a single-color electrostatic image of yellow, magenta, cyan, or black is formed on the photosensitive drum 56. A latent image is formed. A revolver developing unit 50 is disposed on the left side of the photosensitive drum 56 in the drawing. This has a yellow developing unit, a magenta developing unit, a cyan developing unit, and a black developing unit as developing means in a rotating drum-shaped casing, and each developing unit is opposed to the photosensitive drum 56 by rotation. Move sequentially to development position. The yellow developer, magenta developer, cyan developer, and black developer are for developing an electrostatic latent image by attaching yellow toner, magenta toner, cyan toner, and black toner, respectively. An electrostatic latent image for yellow, magenta, cyan, and black is sequentially formed on the photosensitive drum 56, and these images are sequentially developed by the developing units of the revolver developing unit 50, so that a yellow toner image, a magenta toner image, and a cyan toner are developed. A toner image and a black toner image are obtained.

  An intermediate transfer unit is disposed on the downstream side of the photosensitive drum 56 from the development position. This is a belt drive of an intermediate transfer belt 58 stretched by a tension roller 59a, an intermediate transfer bias roller (bias roller) 57 as a transfer means, a secondary transfer backup roller (backup roller) 59b, and a belt drive roller 59c. The roller 59c is rotationally driven to endlessly move clockwise in the figure. The yellow toner image, magenta toner image, cyan toner image, and black toner image developed on the photosensitive drum 56 enter an intermediate transfer nip where the photosensitive drum 56 and the intermediate transfer belt 58 are in contact with each other. Then, while being influenced by the bias from the intermediate transfer bias roller 57, it is superimposed on the intermediate transfer belt 58 and intermediately transferred (primary transfer) to form a four-color superimposed toner image.

  The surface of the photosensitive drum 56 that has passed through the intermediate transfer nip with rotation is cleaned of residual toner by a drum cleaning unit 55 that is a cleaning unit. The drum cleaning unit 55 cleans the transfer residual toner by a cleaning roller to which a cleaning bias is applied, but a cleaning brush made of a fur brush, a mag fur brush, or a cleaning blade may be used. .

  The surface of the photosensitive drum 56 from which the transfer residual toner has been cleaned is neutralized by a neutralizing lamp 54 serving as a neutralizing unit. As the charge removal lamp 54, a fluorescent lamp, a tungsten lamp, a halogen lamp, a mercury lamp, a sodium lamp, a light emitting diode (LED), a semiconductor laser (LD), an electroluminescence (EL), or the like is used. A semiconductor laser is used as the light source of the laser optical device. About these emitted lights, you may make it use only a desired wavelength range by 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.

On the other hand, the registration roller pair 61 that sandwiches the transfer paper (image carrier) 60 that is a recording material fed from a paper feed cassette (not shown) between the two rollers has the transfer paper 60 on the intermediate transfer belt 58. The toner is fed toward the secondary transfer nip where the intermediate transfer belt 58 and the transfer belt 62 are in contact with each other at a timing at which the color superimposed toner image can be superimposed. The four-color superimposed toner images on the intermediate transfer belt 58 are collectively transferred onto the transfer paper 60 under the influence of the secondary transfer bias from the paper transfer bias roller 63 as the secondary transfer means in the secondary transfer nip. Secondary transferred. A full color image is formed on the transfer paper 60 by this secondary transfer. The transfer paper 60 on which the full-color image is formed is sent to the transport belt 64 by the transfer belt 62. The conveyor belt 64 feeds the transfer paper 60 received from the transfer unit into the fixing unit 65. The fixing unit 65 conveys the transferred transfer paper 60 while being sandwiched between fixing nips formed by contact between the heating roller and the backup roller. The full-color image on the transfer paper 60 is fixed on the transfer paper 60 under the influence of heating from the heating roller and pressure applied in the fixing nip.
Although not shown, a bias for adsorbing the transfer paper 60 is applied to the transfer belt 62 and the conveyance belt 64. In addition, a paper neutralization charger that neutralizes the transfer paper 60 and three belt neutralization chargers that neutralize each belt (intermediate transfer belt 58, transfer belt 62, and conveyance belt 64) are provided. The intermediate transfer unit also includes a belt cleaning unit having the same configuration as that of the drum cleaning unit 55, thereby cleaning the transfer residual toner on the intermediate transfer belt 58.

That is, the electrophotographic apparatus of the present invention includes an intermediate transfer unit in addition to the transfer unit that transfers to the intermediate transfer member, and the toner image formed on the electrophotographic photosensitive member by the transfer unit is transferred to the intermediate transfer unit. It is possible to adopt a configuration in which an image is formed on an intermediate transfer member by primary transfer to a medium, and the image on the intermediate transfer member is secondarily transferred onto the recording material by the intermediate transfer unit.
Here, when the image that is secondarily transferred onto the recording material is a color image composed of a plurality of colors of toner, the toner of each color is sequentially superimposed on the intermediate transfer member by the transfer means. An image can be formed on the body, and the image on the intermediate transfer body can be secondarily transferred collectively onto the recording material by the intermediate transfer unit.

In addition, the electrophotographic apparatus of the present invention can have a tandem configuration having a plurality of image forming elements each including at least the electrophotographic photosensitive member of the present invention, the charging unit, the developing unit, and the transfer unit. A fourth embodiment of the electrophotographic apparatus will be described below.
<Fourth embodiment>
FIG. 8 is a schematic diagram showing the configuration of the electrophotographic apparatus according to the fourth embodiment of the present invention. This embodiment is a tandem type electrophotographic apparatus having an intermediate transfer belt 87, and does not share the photosensitive drum (electrophotographic photosensitive member) 80 for each color, but the photosensitive drums 80Y, 80M for the respective colors. 80C and 80Bk (not displayed) are provided. Further, a developing unit (developing unit) 82, a drum cleaning unit (cleaning unit) 85, a static elimination lamp (static elimination unit) 83, a charging roller (charging unit) 84 for uniformly charging the drum, and a bias roller (primary transfer unit) 86 are also provided. , For each color. In the printer shown in FIG. 7, the charging charger 53 is provided as the drum uniform charging means, but in this apparatus, the charging roller 84 is provided. A fur brush 94 is provided as a belt cleaning unit for cleaning the intermediate transfer belt 87. Reference numeral 81 in FIG. 8 indicates an exposure light source.

In addition, a registration roller pair 88, a paper 89 as a recording material, a paper transfer bias roller 90 as a secondary transfer means, a transfer belt 91, a transport belt 92, and a fixing unit 93 are disposed. Since it overlaps with the embodiment, the description is omitted.
In the tandem method, latent image formation (image exposure process) and development of each color can be performed in parallel, so that the image formation speed can be much faster than the revolver method.

[Process cartridge]
The image forming apparatus as described above may be fixedly incorporated in a copying apparatus, facsimile, or printer, but may be incorporated in these apparatuses in the form of a process cartridge. A process cartridge is a single device (part) that contains a photosensitive member and includes at least one means selected from a charging means, an image exposure means, a developing means, a transfer means, a cleaning means, and a static elimination means. .
That is, the electrophotographic photosensitive member of the present invention, charging means for charging the surface of the electrophotographic photosensitive member, image exposure means for forming an electrostatic latent image on the surface of the electrophotographic photosensitive member, and developing the electrostatic latent image At least one selected from developing means for forming a toner image, cleaning means for cleaning the surface of the electrophotographic photosensitive member, and transfer means for transferring the toner image directly to a recording material or transferring it to an intermediate transfer member. It can be set as the structure to comprise. The process cartridge has various shapes and the like, and a general example is shown in FIG.
FIG. 9 is a schematic diagram showing the configuration of an embodiment of a process cartridge according to the present invention.
In the present embodiment, an electrophotographic photosensitive member 16, a charging charger 17 as a charging unit, an image exposing unit 19 as an image exposing unit, a developing roller 20 as a developing unit, and a cleaning brush 18 as a cleaning unit. It comprises.

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

Example 1
An undercoat layer coating solution, a charge generation layer coating solution, and a charge transport layer coating solution having the following composition are sequentially applied onto an aluminum cylinder by dip coating and dried to give a 3.5 μm undercoat layer, 0. A 2 μm charge generation layer and a 23 μm charge transport layer were formed. 1 was produced.

[Undercoat layer coating solution]
Titanium dioxide powder (Ishihara Sangyo, Taibake CR-EL): 400 parts Melamine resin (Dainippon Ink, Super Becamine G821-60): 65 parts Alkyd resin (Dainippon Ink, Beckolite M6401-50): 120 Part 2-butanone: 400 parts

[Charge generation layer coating solution]
Fluorenone-based bisazo pigment of the following structural formula (3): 12 parts Polyvinyl butyral (manufactured by Union Carbide, XYHL): 5 parts 2-butanone: 200 parts Cyclohexanone: 400 parts

[Charge transport layer coating solution]
Polycarbonate resin (Z Polyca, manufactured by Teijin Chemicals): 10 parts Charge transport material of exemplary compound No. 1: 9 parts Amine compound of the above structural formula (2a): 1 part Tetrahydrofuran: 100 parts

The electrophotographic photosensitive member produced as described above is mounted on an electrophotographic process cartridge, mounted on a tandem-type full-color digital copying machine; a Ricoh imagio MPC7500 remodeling machine, and a writing rate 5% chart (on the entire surface of A4, A printing durability test was performed to print a total of 100,000 sheets using a 5% equivalent image as an image area). At that time, the initial image and the image after the printing durability test, the exposure portion potential (VL), and the fluctuation in the job were evaluated.
In order to evaluate the variation within the job, first, the exposed portion potential (VL) of the photoconductor is measured using a surface potentiometer, and then the continuous printing of 50 sheets is set to 1 Job, and this is repeated 10 times, and then the exposed portion potential is set again. Measurement was performed, and <VL after repeated printing>-<first VL> was evaluated as variation within the job. The evaluation results are shown in Table 7 below. In addition to the measurement value, the determination result as to whether or not the correction range can be used for the process is also shown.
<Judgment criteria for intra-job variation>
◎: Level with no problem ○: Level that changes slightly, but does not cause a problem within the range that can be corrected △: Level that changes are clearly recognized and slightly exceeds the allowable range ×: Level that changes greatly and is regarded as a problem

(Examples 2 to 17)
In Example 1, except that one or both of the charge transport material of Exemplified Compound No. 1 and Formula (2a) were used instead of the compounds shown in Table 7 below, the same procedure as in Example 1 was carried out. Photoconductor No. 2-17 were produced. Each of the produced electrophotographic photoreceptors was evaluated in the same manner as in Example 1 for the initial and post-printing test images, the exposure part potential (VL), and the variation in the job. The results are shown in Table 7 below.

(Examples 18 to 22)
In Example 1, the charge generation layer coating solution and the charge transport layer coating solution were changed to the following compositions, and the charge transport materials and amine compounds used in each example were those shown in Table 8 below. Were produced in the same manner as in Example 1 to produce electrophotographic photoreceptors Nos. 18-22. Each of the produced electrophotographic photoreceptors was evaluated in the same manner as in Example 1 for the initial and post-printing test images, the exposure part potential (VL), and the variation in the job. The results are shown in Table 8 below.

[Charge generation layer coating solution]
Titanyl phthalocyanine having powder XD spectrum shown in FIG. 10: 8 parts Polyvinyl butyral (BX-1): 5 parts 2-butanone: 400 parts [Charge transport layer coating solution]
Polycarbonate resin (Z Polyca, manufactured by Teijin Chemicals): 10 parts Charge transport material shown in Table 8 below: 8 parts Amine compound shown in Table 8 below: 0.5 parts Tetrahydrofuran: 100 parts

(Examples 23 to 27)
In Example 1, the charge transport layer coating solution was changed to the following composition, and the charge transport material and amine compound used in each Example were the same as those shown in Table 9 below. Thus, electrophotographic photoreceptors Nos. 23 to 27 were produced. Each of the produced electrophotographic photoreceptors was evaluated in the same manner as in Example 1 for the initial and post-printing test images, the exposure part potential (VL), and the variation in the job. The results are shown in Table 9 below.
[Charge transport layer coating solution]
Polycarbonate resin (Z polycarbonate, manufactured by Teijin Chemicals): 10 parts Charge transport material shown in Table 9 below: 8 parts Amine compound shown in Table 9 below: 2 parts Tetrahydrofuran: 100 parts

(Comparative Example 1)
An electrophotographic photoreceptor No. 28 was produced in the same manner as in Example 1, except that the amine compound of the structural formula (2a) was not added to the charge transport layer coating solution in Example 1. The produced electrophotographic photoreceptor No. 28 was evaluated in the same manner as in Example 1 for the initial image and the image after the printing durability test, the exposure portion potential (VL), and the fluctuation within the job. The results are shown in Table 10 below.

(Comparative Example 2)
In the same manner as in Example 1, except that the compound of the following structural formula (4) was used instead of the amine compound of the structural formula (2a) used in the charge transport layer coating solution in Example 1, the electrophotographic photosensitive member was used. Body No. 29 was produced. The produced electrophotographic photoreceptor No. 29 was evaluated in the same manner as in Example 1 for the initial and post-printing test images, the exposure part potential (VL), and the variation within the job. The results are shown in Table 10 below.

(Comparative Example 3)
In the same manner as in Example 1 except that the compound of the following structural formula (5) was used instead of the amine compound of the structural formula (2a) used in the charge transport layer coating solution in Example 1, the electrophotographic photosensitive member was used. Body No. 30 was produced. The produced electrophotographic photoreceptor No. 30 was evaluated in the same manner as in Example 1 for the initial image and the image after the printing durability test, the exposure portion potential (VL), and the fluctuation within the job. The results are shown in Table 10 below.

(Comparative Example 4)
In the same manner as in Example 1, except that a compound of the following structural formula (6) was used instead of the amine compound of the structural formula (2a) used in the charge transport layer coating solution in Example 1, the electrophotographic photosensitive member was used. Body No. 31 was produced. The produced electrophotographic photoreceptor No. 31 was evaluated in the same manner as in Example 1 for images after initial and post-printing tests, exposure portion potential (VL), and in-job variation. The results are shown in Table 10 below.

(Comparative Example 5)
In the same manner as in Example 1, except that the compound of the following structural formula (7) was used instead of the amine compound of the structural formula (2a) used in the charge transport layer coating solution in Example 1, the electrophotographic photosensitive member was used. Body No. 32 was produced. The produced electrophotographic photoreceptor No. 32 was evaluated in the same manner as in Example 1 for the initial and post-printing test images, exposure part potential (VL), and in-job variation. The results are shown in Table 10 below.

(Comparative Example 6)
In the same manner as in Example 1 except that the charge transport material (Exemplary Compound No. 1) used in the charge transport layer coating solution in Example 1 was changed to the compound of the following structural formula (8), an electrophotographic photoreceptor No. .33 was produced. The produced electrophotographic photoreceptor No. 33 was evaluated in the same manner as in Example 1 for the initial image and the image after the printing durability test, the exposure part potential (VL), and the fluctuation in the job. The results are shown in Table 11 below.

(Comparative Example 7)
In the same manner as in Example 1 except that the charge transport material (Exemplary Compound No. 1) used in the charge transport layer coating solution in Example 1 was changed to the compound of the following structural formula (9), an electrophotographic photoreceptor No. .34 was produced. The produced electrophotographic photoreceptor No. 34 was evaluated in the same manner as in Example 1 for images after initial and post-printing tests, exposure part potential (VL), and in-job variation. The results are shown in Table 11 below.

(Comparative Example 8)
In the same manner as in Example 1, except that the charge transport material (Exemplary Compound No. 1) used in the charge transport layer coating solution in Example 1 was changed to the compound of the following structural formula (10), the electrophotographic photoreceptor No. .35 was produced. The produced electrophotographic photoreceptor No. 35 was evaluated in the same manner as in Example 1 for the initial and post-printing test images, exposure part potential (VL), and in-job variation. The results are shown in Table 11 below.

From the above evaluation results, the photoconductor of the present invention has stable photoconductor characteristics even after repeated use over a long period of time, does not cause image deterioration such as image density reduction and image blurring, and has less fluctuation in the job. It does not increase much even after repeated use.
On the other hand, in the case of Comparative Example 1 which does not contain the amine compound represented by the general formula (2) and Comparative Examples 2 to 4 using other amine compounds other than the amine compound represented by the general formula (2) The initial image quality is good, but image deterioration due to repeated use cannot be suppressed. In addition, when the amine compound of Comparative Example 5 is used, a good image can be obtained even after repeated use. However, variation within the job cannot be suppressed, and in the case where the same image is output continuously, the image density or A color change will occur.
Moreover, the comparative example combined with other charge transport materials other than the charge transport material represented by the said General formula (1) including the amine compound (Exemplary compound No. 1) represented by the said General formula (2). In the case of 6 to 8, image degradation after repeated use is slight, but in this case as well, fluctuations in the job cannot be suppressed.
As described above, according to the present invention, there is provided an electrophotographic photoreceptor in which the photoreceptor characteristics are stable even when used repeatedly for a long time, the fluctuation in the job is suppressed, and a high-quality image can be stably obtained over a long period. be able to.
Further, according to the present invention, an electrophotographic method, an electrophotographic apparatus, and an electrophotographic apparatus capable of outputting an image with little change in image density and color, that is, excellent image quality consistency, by using the electrophotographic photosensitive member. A process cartridge is provided. As a result, it is possible to cope with higher durability and higher stability of the organic photoreceptor required from the general office area to the SOHO area or the light printing area.

(FIGS. 1 to 4)
31 Conductive Support 33 Photosensitive Layer 35 Charge Generation Layer 37 Charge Transport Layer 39 Protective Layer (FIG. 5)
1 Electrophotographic photoreceptor (photoreceptor)
2 Charger lamp 3 Charger charger 5 Image exposure unit 6 Development unit 7 Charger before transfer 8 Registration roller 9 Transfer paper 10 Transfer charger 11 Separation charger 12 Separation claw 13 Charger before cleaning 14 Fur brush 15 Cleaning blade (FIG. 6)
21 Photoconductors 22a, 22b Driving roller 23 Charger 24 Light source 25 Transfer charger 26 Light source 27 Cleaning brush 28 Light source (FIG. 7)
L exposure (laser light)
50 Revolver Development Unit 53 Charger Charger 54 Discharge Lamp 55 Drum Cleaning Unit 56 Drum-shaped Photoconductor (Photoconductor Drum)
57 Intermediate transfer bias roller (bias roller)
58 Intermediate transfer belt 59a Tension roller 59b Secondary transfer backup roller (backup roller)
59c Belt drive roller 60 Transfer paper (image carrier)
61 Registration Roller 62 Transfer Belt 63 Paper Transfer Bias Roller 64 Transport Belt 65 Fixing Unit (FIG. 8)
80 Photosensitive drum 81 Exposure light source 82 Development unit 83 Static elimination lamp 84 Charging roller 85 Drum cleaning unit 86 Bias roller 87 Intermediate transfer belt 88 Registration roller 89 Paper 90 Paper transfer bias roller 91 Transfer belt 92 Transport belt 93 Fixing unit 94 Fur brush ( (Fig. 9)
16 Electrophotographic photosensitive member 17 Charger charger 18 Cleaning brush 19 Image exposure unit 20 Developing roller

Japanese Unexamined Patent Publication No. 01-230055 Japanese Patent Laid-Open No. 03-172852 (Japanese Patent No. 2864583) JP 2002-333731 A (Patent No. 3901547) Japanese Patent Laid-Open No. 04-56866 JP 2004-258253 A (Patent No. 4101676) JP 2009-42564 A

Claims (9)

In an electrophotographic photosensitive member having a photosensitive layer on a conductive support, the photosensitive layer contains a charge transport material represented by the following general formula (1) and an amine compound represented by the following general formula (2). An electrophotographic photosensitive member characterized by comprising:

[In Formula (1), A < ₁ >, A < ₂ > may have either the alkyl group which may have a phenyl group, or a methyl group, an ethyl group, t-butyl group, a methoxy group, and an ethoxy group. Represents an aryl group, which may be the same or different. Ar represents a condensed polycyclic aromatic hydrocarbon group which may have either a methyl group or a t-butyl group. ]

[In formula (2), A and B are each selected from the groups represented by the following formula (i) or (ii), and may be the same or different.
(I) _-CH 2 X
_(Ii) -CH 2 _CH 2 Y
[However, in the formula (i) or (ii), X and Y each represents an aromatic residue, a cycloalkyl group or a heterocycloalkyl group, and these may have a substituent. ]] A charging step for charging the surface of the electrophotographic photosensitive member according to claim 1;
An image exposure step of forming an electrostatic latent image on the electrophotographic photoreceptor;
A developing step of developing the electrostatic latent image to form a toner image;
An electrophotographic method comprising repeatedly performing a transfer step of transferring the toner image directly to a recording material or transferring the toner image to a recording material via an intermediate transfer member. The electrophotographic method is a digital method,
3. The image exposure step of forming an electrostatic latent image on the electrophotographic photosensitive member by light irradiation using a semiconductor laser (LD) or a light emitting diode (LED) as a light source. The electrophotographic method described. An electrophotographic photoreceptor according to claim 1;
Charging means for charging the surface of the electrophotographic photosensitive member;
Image exposure means for forming an electrostatic latent image on the surface of the electrophotographic photosensitive member;
Developing means for developing the electrostatic latent image to form a toner image;
Transfer means for directly transferring the toner image to a recording material or transferring it to an intermediate transfer member;
An electrophotographic apparatus comprising: The electrophotographic apparatus is a digital system,
5. The electron according to claim 4, wherein the image exposure means uses a semiconductor laser (LD) or a light emitting diode (LED) that forms an electrostatic latent image on the surface of the electrophotographic photosensitive member as a light source. Photo equipment.   6. The tandem type structure having a plurality of image forming elements each including at least the electrophotographic photosensitive member, the charging unit, the developing unit, and the transfer unit. Electrophotographic device. In addition to the transfer means for transferring to the intermediate transfer body, an intermediate transfer means is provided,
The toner image formed on the electrophotographic photoreceptor is primarily transferred to the intermediate transfer member by the transfer unit to form an image on the intermediate transfer member, and the image on the intermediate transfer member is formed by the intermediate transfer unit. The electrophotographic apparatus according to claim 4, wherein the image is secondarily transferred onto the recording material. The image that is secondarily transferred onto the recording material is a color image made of a plurality of colors of toner,
The transfer unit forms an image on the intermediate transfer member by sequentially superimposing toner of each color on the intermediate transfer member, and the intermediate transfer unit collects the images on the intermediate transfer member on the recording material. The electrophotographic apparatus according to claim 7, wherein the image is subjected to secondary transfer. An electrophotographic photoreceptor according to claim 1;
Charging means for charging the surface of the electrophotographic photosensitive member; image exposing means for forming an electrostatic latent image on the surface of the electrophotographic photosensitive member; developing means for developing the electrostatic latent image to form a toner image; And at least one selected from a cleaning unit that cleans the surface of the photosensitive member and a transfer unit that directly transfers the toner image to a recording material or transfers it to an intermediate transfer member. Process cartridge.

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