JP2003215819A - Electrophotographic photoreceptor for reversal development, electrophotographing method using the same, electrophotographing device, and process cartridge for the electrophotographing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a photoreceptor for reversal development which can output a stable image with high resolution even when repeatedly used. <P>SOLUTION: The electrophotographic photoreceptor for reversal development which has at least a charge generation layer and a charge transport layer provided on a conductive base having its surface anodized for filming is obtained by carrying out electrostatic charging and exposure processing before the photoreceptor is used for an electrophotographing device after the charge generation layer and charge transport layer for formed. <P>COPYRIGHT: (C)2003,JPO

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 in an electrophotographic apparatus using reversal development, and more particularly to an electrophotographic photosensitive member having less background stains and black spots generated by reversal development. The present invention relates to an electrophotographic method, an electrophotographic apparatus, and an electrophotographic process cartridge used.

[0002]

2. Description of the Related Art In recent years, the development of information processing system machines using electrophotography has been remarkable. In particular, an optical printer that converts information into a digital signal and records information by light has been remarkably improved in print quality and reliability. This digital recording technology has been applied not only to printers but also to ordinary copying machines, and so-called digital copying machines have been developed. Further, since the conventional analog copying machine equipped with this digital recording technology is provided with various information processing functions, it is expected that the demand thereof will further increase in the future.

In such a digital copying machine or digital printer, the image area ratio of the original is usually 10%.
Because of the following levels, there is a reversal development (negative / positive development) method that writes in the image area in consideration of deterioration of the light source and light fatigue of the photoconductor, and develops the toner image on the part where the potential of the photoconductor is attenuated. Mainstream. This reversal development method requires less light irradiation to the photoconductor, and is a development method advantageous for the photoconductor in consideration of light fatigue during repeated use.
If a slight defect is present on the photoconductor and a phenomenon such as a potential leak occurs, point defects (background stains, black spots, etc.) occur on the background portion (white background) that is not in the original document. This defect may be mistaken for a dot in a drawing, a period or a comma in an English manuscript, and can be said to be a fatal defect in an image.

Most of these defects are mainly caused by a local potential leak of the photoconductor, and it is possible to improve the pressure resistance of the photoconductor, the uniformity of charging, and the uniformity of potential holding. It is a major issue. In view of this point, attempts have been made to provide an intermediate layer (undercoat layer) between the conductive support and the photosensitive layer. The structure of the intermediate layer is a layer in which a binder resin is a main component and a filler is dispersed if necessary. When the binder resin is used alone, the binder resin is a material having a high electrical insulation property, and therefore the thickness of the intermediate layer needs to be extremely thin, and in most cases, the thickness is 1 μm or less. In such a case, since the forming method is performed by a wet coating method, it is difficult to avoid pinholes in the coating film, and the expected effect cannot be obtained. On the other hand, most of the mainstream photoconductors are hole transport type photoconductors, so by adding an electron conductive filler to the intermediate layer, the intermediate layer can be made thicker and pinholes can be avoided. Came.

However, in the intermediate layer composed of the filler resin dispersion system, the finely divided submicron filler is not only costly, but also is too bulky, resulting in poor workability and production. Not to be used on. Therefore, submicron (minimum primary particle 0.3
Fine particles of about (μm) are often used. For this reason, re-aggregation of the filler may occur in the dispersion liquid or during coating film formation, resulting in a coating film defect of 1 μm or more, and for designing a photoreceptor having uniform charging property and potential holding property. No intermediate layer is formed.

On the other hand, a method of providing an anodic oxide film for directly forming a barrier layer on a conductive support has been studied with an idea different from that of the intermediate layer. In this method, an aluminum substrate, which is a conductive support, is anodized using an electrolyte such as sulfuric acid or oxalic acid to form an aluminum oxide film typified by alumite on the surface of the support. The photoconductor having this oxide film has a high pressure resistance, the chargeability is not significantly deteriorated even when the photoconductor is repeatedly used in the electrophotographic apparatus, and the increase of the point defects in the background portion is not observed so much. However, there are many point defects in the initial stage of using the photoconductor, which causes a problem in practical use.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and when a photoreceptor using a conductive support having an anodized film is used for reversal development, the initial use of the photoreceptor is considered. It is an object of the present invention to provide a reversal development photoreceptor in which a point defect in the background portion that occurs in a state is prevented. Also,
It is an object of the present invention to provide a photoconductor that can output a stable image with high resolution even after repeated use. Further, the present invention provides an electrophotographic method, an electrophotographic apparatus, and an electrophotographic process cartridge that can obtain stable images with few abnormal images even after repeated use, and that can obtain high-resolution and highly durable images. To aim.

[0008]

As described above, when a photoreceptor having an anodized film on the surface of a conductive support is used,
It is possible to prevent defects in repeated use of the photoconductor, and it has a significantly superior effect to the photoconductor using the undercoat layer containing a resin as a main component. However, although it seems to be a phenomenon peculiar to the photoconductor using the anodized film, the degree of background stain is large at the initial stage of use of the photoconductor.

Certainly, it is a fact that by repeatedly using the photoconductor in the electrophotographic apparatus, the degree of background stain is improved to a level that can withstand actual use. However, it is unacceptable to the user that the background stain level is bad in the initial state and the level is not the actual use level. In addition, when an image inspection or the like is performed at the time of shipping the photoconductor, the ability of the photoconductor cannot be accurately grasped.

In view of the above points, the present inventor has conducted extensive studies, and as a result, either the charging and exposing process or the charging only process is performed before the photosensitive member is used in an electrophotographic apparatus. By carrying out the above processing, it was found that a good image free from background stain can be obtained from the initial state in which the photoconductor is mounted in the electrophotographic apparatus, and the present invention has been completed.

That is, according to the present invention, firstly, in an electrophotographic photoreceptor for reversal development in which at least a charge generation layer and a charge transport layer are provided on a conductive support whose surface is anodized. Provided is an electrophotographic photoreceptor for reversal development, which comprises performing charging and exposure treatment after forming a charge generation layer and a charge transport layer and before using the photoreceptor in an electrophotographic apparatus.

Secondly, in the electrophotographic photosensitive member for reversal development according to the first aspect, the light absorption peak of the charge generating substance used in the photosensitive member is the longest wavelength side in the exposure in the charging and exposure processing. An electrophotographic photoreceptor for reversal development is provided which is characterized in that only light having a wavelength longer than the peak value of the peak is used.

Thirdly, in the electrophotographic photosensitive member for reversal development according to the first aspect, in the exposure in the charging and exposure processing, when the irradiation light has an emission peak, the emission half-value wavelength is the charge transport layer. Used for the above, the absorption peak wavelength of the charge state of the charge-transporting substance is different from the absorption peak wavelength of the charge-transporting substance. When the wavelength is longer than the peak wavelength, and the threshold value has a threshold value and the emission component has a wavelength shorter than the threshold value, the threshold half value wavelength should be shorter than the shortest absorption peak wavelength of the charge state of the charge transport material. An electrophotographic photosensitive member for reversal development is provided.

Fourth, in an electrophotographic photoreceptor for reversal development in which at least a charge generation layer and a charge transport layer are provided on a conductive support whose surface is anodized, the charge generation layer and the charge transport layer are provided. Provided is an electrophotographic photoreceptor for reversal development, which is characterized in that after formation, before use of the photoreceptor in an electrophotographic apparatus, only charging is performed.

Fifth, in the electrophotographic photosensitive member for reversal development according to the fourth aspect, the voltage used in the charging process is
Provided is an electrophotographic photoreceptor for reversal development, which is an alternating electric field obtained by superposing an AC voltage on a DC voltage.

Sixth, in the electrophotographic photoreceptor for reversal development according to any one of the first to fifth aspects, the absolute value of the electric field strength applied to the photoreceptor by the above charging is 6 V / μm or more, 10
There is provided an electrophotographic photosensitive member for reversal development, which is characterized by having 0 V / μm or less.

Seventhly, in the electrophotographic photosensitive member for reversal development according to any one of the first to sixth aspects, the photosensitive member is a cylindrical photosensitive member, and the charging treatment is performed by a contact charging member or a proximity arrangement. There is provided an electrophotographic photosensitive member for reversal development, which is performed by the charged charging member.

Eighth, for the reversal development electrophotographic photosensitive member according to the seventh or eighth, the reversal development is characterized in that the contact charging member or the closely arranged charging member is in the shape of a roller. An electrophotographic photoreceptor is provided.

Ninth, for the reversal development electrophotographic photoreceptor according to any one of the first to eighth aspects, the reversal development is characterized in that the film thickness of the anodized film is from 5 μm to 15 μm. An electrophotographic photoreceptor is provided.

Tenth, in the electrophotographic photoreceptor for reversal development according to any one of the above first to ninth, the outermost layer of the photoreceptor is a charge transport layer, and the charge transport layer has an electron donating group. Provided is an electrophotographic photoreceptor for reversal development, which comprises a polymer.

Eleventh, in the electrophotographic photoconductor for reversal development according to any one of the first to ninth aspects, a protective layer is provided on the outermost surface of the photoconductor, the electrophotographic photoconductor for reversal development. The body is provided.

Twelfth, in the electrophotographic photoreceptor for reversal development according to the eleventh aspect, the protective layer contains a low molecular charge transporting substance or a polymer having an electron donating property. An electrophotographic photoreceptor for use is provided.

Thirteenth, there is provided an electrophotographic photoreceptor for reversal development according to the eleventh or twelfth aspect, characterized in that a protective layer contains a filler. It

Fourteenth, in the electrophotographic photoreceptor for reversal development according to any one of the first to thirteenth, the film thickness of the photosensitive layer (when a protective layer is provided, the photosensitive layer + the protective layer). An electrophotographic photoreceptor for reversal development is provided having a total film thickness of 20 μm or less.

Fifteenthly, in the electrophotographic photoreceptor for reversal development according to any one of the first to fourteenth aspects, the charge generating substance contained in the charge generating layer is represented by the following formula (I). Provided is an electrophotographic photoreceptor for reversal development, which is an azo pigment.

[0026]

[Chemical 3] In the formula, Cp ₁ and Cp ₂ represent coupler residues. R ₂₀₁ ,
R ₂₀₂ represents a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group or a cyano group, and may be the same or different. Cp ₁ and Cp ₂ are as follows (II)
It is represented by a formula.

[Chemical 4] In the formula, R ₂₀₃ represents a hydrogen atom, an alkyl group such as a methyl group or an ethyl group, or an aryl group such as a phenyl group. R
₂₀₄ , R ₂₀₅ , R ₂₀₆ , R ₂₀₇ and R ₂₀₈ are each a hydrogen atom, a nitro group, a cyano group, a halogen atom such as fluorine, chlorine, bromine or iodine, an alkyl such as a trifluoromethyl group, a methyl group or an ethyl group. Group, an alkoxy group such as a methoxy group and an ethoxy group, a dialkylamino group and a hydroxyl group, and Z is an atomic group necessary for constituting a substituted or unsubstituted aromatic carbocycle or a substituted or unsubstituted aromatic heterocycle. Represents

Sixteenth, in the electrophotographic photoreceptor for reversal development described in the fifteenth, Cp ₁ and C of the above azo pigments are used.
There is provided an electrophotographic photosensitive member for reversal development, which is characterized in that p ₂ is different from each other.

Seventeenth, in the electrophotographic photosensitive member for reversal development according to any one of the first to fourteenth aspects, the charge generating substance contained in the charge generating layer is a Bragg angle with respect to a characteristic X-ray of CuKα. Provided is an electrophotographic photoreceptor for reversal development, which is titanyl phthalocyanine having a maximum diffraction peak at least at 27.2 ° as a 2θ diffraction peak (± 0.2 °).

Eighteenth, using the electrophotographic photoreceptor for reversal development according to any one of the first to seventeenth aspects, at least charging, image exposure, reversal development, and image transfer are repeated. An electrophotographic method is provided.

Nineteenth, at least the electrophotographic photoreceptor for reversal development according to any one of the first to seventeenth aspects, a charging means, an image exposure means, a reversal development means and a transfer means are provided. An electrophotographic device is provided.

In a twentieth aspect, there is provided a process cartridge for an electrophotographic apparatus for reversal development, comprising the reversal development electrophotographic photosensitive member according to any one of the first to seventeenth aspects. .

Conventionally, there is a technique in which an electrophotographic photosensitive member is repeatedly subjected to corona charging and exposure or charged before being used in an electrophotographic apparatus as in the present invention. That is, JP-A-60-203950 discloses that a function-separated electrophotographic photoreceptor having an undercoat layer, a charge generation layer, and a charge transport layer on a conductive support is corona charged before being used in an electrophotographic apparatus. Further, it is described that by repeating exposure and performing charging treatment, there are effects of preventing white spots in an image at high temperature and high humidity and improving density. In addition, JP-A-60-
203951 discloses an undercoat layer on a conductive support,
Charge generation layer, as a method for producing a function-separated electrophotographic photoreceptor having a charge transport layer, after coating the charge generation layer, by repeating corona charging and exposure or charging treatment before stacking the charge transport layer, high temperature It is described that it has an effect of preventing white spots in an image at high humidity and improving density. Both of them are intended to prevent a decrease in the surface potential of the dark part caused by carrier injection into the charge transport layer through the undercoat layer and the charge generation layer.

However, since the electrophotographic process using the photoconductor is used in the category of regular development (positive / positive development), the application used is different from that of the present invention. The normal writing rate for originals excludes solid images.
The maximum is about 10%. Even if the white spots in the positive / positive development and the black spots in the negative / positive development are similar phenomena, their influences are completely different. Therefore, even if the effect of preventing white spots in the positive / positive development is recognized, the effect in the negative / positive development is not always sufficient for practical use.

Further, as the constitution of the photoconductor, an undercoat layer containing a resin as a main component is used, and the constitution of the photoconductor is obviously different, and the mechanism in the above-mentioned treatment (repeating corona charging and exposure or charging treatment) is Clearly different. In the present invention, the improvement of the barrier property is promoted by modifying the anodic oxide film, and by extension, the point defects in the background portion at the initial stage of the photoconductor are reduced.

Further, in the above-mentioned prior art, the conditions in the above-mentioned processing are not clear, and basically the above-mentioned processing tends to promote fatigue of the photoconductor. In some cases, and the residual potential may increase). In particular, an increase in the residual potential of the photoconductor causes a decrease in image density in negative / positive development, which is a very serious problem.

According to the result of examination by the present inventor, even if a large number of point defects are generated in the initial stage, if they are forcibly repeatedly used thereafter, the number of point defects does not increase, but rather tends to decrease. I understood. The cause of this is not clear, but a certain barrier is formed at the oxide film surface or at the oxide film / photosensitive layer (charge generation layer) interface by the electric field applied by repeated use of the photoreceptor.
It is considered that since the barrier property is enhanced, the number of local potential leak points is reduced, and the above point defects are reduced. In the present invention, by performing the above-mentioned specific processing before mounting the electrophotographic apparatus on the photoconductor, an effect equivalent to the effect of reducing point defects due to barrier formation in repeated use of the photoconductor is obtained, and the state of the photoconductor is changed. It can be used in a stable state.

[0037]

DETAILED DESCRIPTION OF THE INVENTION The constitution of the electrophotographic photosensitive member of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing the layer structure of the electrophotographic photosensitive member of the present invention. A charge generating layer 35 is provided on a conductive support 31 having an anodized film 33 on the surface thereof, and a charge transport layer is further provided thereon. A layer 37 is provided. FIG. 2 is a diagram showing another configuration example of the electrophotographic photosensitive member of the present invention, in which a charge transport layer 37 is provided on a conductive support 31 having an anodized film 33 provided on the surface thereof, and further thereon. The charge generation layer 35 is provided. FIG. 3 is a diagram showing still another configuration of the present invention, in which a charge generation layer 35, a charge transport layer 37, and a protective layer 39 are sequentially provided on a conductive support 31 having an anodized film 33 provided on the surface thereof. Has been.

As the conductive support 31, the volume resistance 10
Those exhibiting conductivity of ¹⁰ Ω · cm or less, for example, metal such as aluminum, nickel, chromium, nichrome, copper, gold, silver and platinum, metal oxide such as tin oxide and indium oxide, by vapor deposition or sputtering, Film or cylindrical plastic, paper coated, or aluminum, aluminum alloy, nickel, stainless steel, etc. plates and the like, after being formed into a raw tube by a method such as extrusion or drawing, cutting, superfinishing, polishing, etc. It is possible to use a surface-treated tube or the like. Further, the endless nickel belt and the endless stainless belt disclosed in JP-A-52-36016 can also be used as the conductive support 31.

In addition, the conductive support 31 of the present invention may be formed by coating the support with conductive powder dispersed in a suitable binder resin. As the conductive powder, carbon black, acetylene black, aluminum, nickel, iron, nichrome, copper, zinc,
Examples thereof include metal powder such as silver, metal oxide powder such as conductive tin oxide and ITO. Further, the binder resin used at the same time, 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, polyvinyltoluene, poly-N-vinylcarbazole, acrylic resin, silicone resin, epoxy resin, melamine resin, urethane resin, phenol resin, alkyd resin, and other thermoplastic, thermosetting resin or photocurable resin. To be Such a conductive layer can be provided by dispersing and coating the conductive powder and the binder resin in a suitable solvent such as tetrahydrofuran, dichloromethane, methyl ethyl ketone or toluene.

Among these, the cylindrical support made of aluminum, which can be easily subjected to the anodic oxide film treatment, can be most preferably used. Aluminum here means
It includes either pure aluminum or aluminum alloy. Specifically, JIS 1000 series, 300
The 0s and 6000s of aluminum or aluminum alloy are most suitable.

Next, the anodic oxide film 33 will be described. The anodic oxide film is various metals, various alloys are anodized in an electrolyte solution, among them aluminum or aluminum alloy anodized film in the electrolyte solution called alumite coating on the photoreceptor of the present invention Is the most suitable. The anodizing treatment is carried out in an acidic bath of chromic acid, sulfuric acid, oxalic acid, phosphoric acid, boric acid, sulfamic acid or the like. Of these, treatment with a sulfuric acid bath is most suitable. For example, sulfuric acid concentration: 10
-20%, bath temperature: 5-25 ° C, current density: 1-4 A / d
m2, electrolysis voltage: 5 to 30 V, treatment time: 5 to 60 minutes, but not limited thereto.

Since the anodic oxide film thus prepared is porous and has high insulation, the surface is very unstable. Therefore, there is a change over time after fabrication,
The physical properties of the anodized film tend to change. In order to avoid this, it is desirable to further subject the anodized film to a sealing treatment. The sealing treatment includes a method of immersing the anodic oxide film in an aqueous solution containing nickel fluoride or nickel acetate, a method of immersing the anodic oxide film in boiling water, a method of treating with pressurized steam, and the like. Of these, the method of immersing in an aqueous solution containing nickel acetate is most preferable.

Subsequent to the sealing treatment, a cleaning treatment of the anodized film is performed. The main purpose of this is to remove excess substances such as metal salts attached by the sealing treatment. If this remains excessively on the surface of the support (anodized film),
Not only does this adversely affect the quality of the coating film formed thereon, but in general, the low resistance component remains, which in turn causes the background stain. The cleaning may be performed once with pure water, but is usually performed at another stage. On this occasion,
It is preferred that the final wash solution be as clean (deionized) as possible. In addition, it is desirable to perform physical scrubbing cleaning with a contact member in one of the other cleaning steps.

The film thickness of the anodized film formed as described above is preferably about 5 to 15 μm. If it is thinner than this, the effect of the barrier property as an anodized film is not sufficient, and if it is thicker than this, the time constant as an electrode becomes too large and the generation of residual potential and the response of the photoreceptor deteriorate. There is a case.

Next, the photosensitive layer will be described. The photosensitive layer is composed of a charge generation layer 35 and a charge transport layer 37.

The charge generating layer 35 is a layer containing a charge generating substance as a main component. For the charge generation layer 35, the charge generation substance is dispersed in a suitable solvent together with a binder resin as needed using a ball mill, an attritor, a sand mill, ultrasonic waves, etc., and this is coated on a conductive support and dried. It is formed by

As the binder resin used in the charge generation layer 35 as required, polyamide, polyurethane, epoxy resin, polyketone, polycarbonate, silicon resin, acrylic resin, polyvinyl butyral, polyvinyl formal, polyvinyl ketone, polystyrene, polysulfone, Poly-N-vinylcarbazole, polyacrylamide, polyvinylbenzal, polyester, phenoxy resin, vinyl chloride-vinyl acetate copolymer, polyvinyl acetate, polyphenylene oxide, polyamide, polyvinylpyridine, cellulosic resin, casein, polyvinyl alcohol, polyvinyl Examples thereof include pyrrolidone.
Among them, polyvinyl acetal typified by polyvinyl butyral is favorably used, and particularly has an acetylation degree of 4 m.
A polyvinyl acetal (butyral) of ol% or more is preferably used. The amount of the binder resin is 100
0 to 500 parts by weight, preferably 10 to 30 parts by weight
0 parts by weight is suitable.

Known charge generating materials can be used in the charge generating layer 35, and representative examples thereof include monoazo pigments, disazo pigments, trisazo pigments, perylene pigments, perinone pigments, quinacridone pigments, and quinones. Examples include condensed polycyclic compounds, squaric acid dyes, phthalocyanine pigments, naphthalocyanine pigments, and azurenium salt dyes.

Among them, azo pigments and / or phthalocyanine pigments are effectively used. In particular, the azo pigment represented by the following structural formula (I) and titanyl phthalocyanine (in particular, the maximum diffraction peak at at least 27.2 ° as the diffraction peak (± 0.2 °) of Bragg angle 2θ with respect to the characteristic X-ray of CuKα) Titanyl phthalocyanine) can be effectively used.

[0050]

[Chemical 5] In the formula, Cp ₁ and Cp ₂ represent coupler residues. R ₂₀₁ ,
R ₂₀₂ represents a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group or a cyano group, and may be the same or different. Cp ₁ and Cp ₂ are as follows (II)
It is represented by a formula.

[Chemical 6] In the formula, R ₂₀₃ represents a hydrogen atom, an alkyl group such as a methyl group or an ethyl group, or an aryl group such as a phenyl group. R
₂₀₄ , R ₂₀₅ , R ₂₀₆ , R ₂₀₇ and R ₂₀₈ are each a hydrogen atom, a nitro group, a cyano group, a halogen atom such as fluorine, chlorine, bromine or iodine, an alkyl such as a trifluoromethyl group, a methyl group or an ethyl group. Group, an alkoxy group such as a methoxy group and an ethoxy group, a dialkylamino group and a hydroxyl group, and Z is an atomic group necessary for constituting a substituted or unsubstituted aromatic carbocycle or a substituted or unsubstituted aromatic heterocycle. Represents

[0051] In particular, said Cp ₁ and asymmetric azo pigment Cp ₂ are different structures, Cp ₁ and Cp ₂ than the target azo pigments have the same structure, if the photosensitivity is good many of the photoconductor It can be used effectively because it can support smaller diameters and faster use processes.

The Bragg angle 2θ diffraction peak (±
Among the titanyl phthalocyanines having a maximum diffraction peak at 27.2 ° as 0.2 °), the lowest angle is 7.3.
Titanyl phthalocyanine having a peak at (°)
No. 01-19871) can be used particularly effectively. These charge generating substances may be used alone or in combination of two or more.

Solvents used for forming the charge generation layer include isopropanol, acetone, methyl ethyl ketone, cyclohexanone, tetrahydrofuran, dioxane, ethyl cellosolve, ethyl acetate, methyl acetate, dichloromethane, dichloroethane, monochlorobenzene, cyclohexane, toluene, xylene, Examples thereof include ligroin, and ketone-based solvents, ester-based solvents, and ether-based solvents are particularly preferably used. As the coating method of the coating liquid, 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 0.01
About 5 μm is suitable, and preferably 0.1 to 2 μm
Is.

The charge transport layer 37 can be formed by dissolving or dispersing the charge transport substance and the binder resin in a suitable solvent, coating the resultant on the charge generating layer, and drying. Also,
If necessary, a plasticizer, a leveling agent, an antioxidant and the like can be added.

The charge transport material includes a hole transport material and an electron transport material. Examples of the charge transport substance include chloranil, bromanil, tetracyanoethylene, tetracyanoquinodimethane, 2,4,7-trinitro-9-fluorenone, 2,4,5,7-tetranitro-9-fluorenone and 2,4. , 5,7-Tetranitroxanthone,
2,4,8-trinitrothioxanthone, 2,6,8-
Examples thereof include electron-accepting substances such as trinitro-4H-indeno [1,2-b] thiophen-4-one, 1,3,7-trinitrodibenzothiophene-5,5-dioxide, and benzoquinone derivative.

As the hole-transporting substance, poly-N-vinylcarbazole and its derivative, poly-γ-carbazolylethylglutamate and its derivative, pyrene-formaldehyde condensate and its derivative, polyvinylpyrene, polyvinylphenanthrene, polysilane, Oxazole derivative, oxadiazole derivative, imidazole derivative, monoarylamine derivative, diarylamine derivative, triarylamine derivative, stilbene derivative,
α-phenylstilbene derivative, benzidine derivative, diarylmethane derivative, triarylmethane derivative, 9
-Styrylanthracene derivatives, pyrazoline derivatives, divinylbenzene derivatives, hydrazone derivatives, indene derivatives, butadiene derivatives, pyrene derivatives, bisstilbene derivatives, enamine derivatives and other known materials can be used. These charge transport materials may be used alone or in combination of two or more.

As the binder resin, polystyrene, styrene-acrylonitrile copolymer, styrene-butadiene copolymer, styrene-maleic anhydride copolymer, polyester, polyvinyl chloride, vinyl chloride-vinyl acetate copolymer, poly Vinyl acetate, polyvinylidene chloride, polyalate, phenoxy resin, polycarbonate, cellulose acetate resin, ethyl cellulose resin, polyvinyl butyral, polyvinyl formal, polyvinyl toluene, poly-N-vinylcarbazole, acrylic resin, silicone resin, epoxy resin, melamine resin, urethane Thermoplastic or thermosetting resins such as resins, phenolic resins and alkyd resins can be mentioned.

The amount of the charge transport material is 20 to 300 parts by weight, preferably 40 to 150 parts by weight, based on 100 parts by weight of the binder resin.
Parts by weight are suitable. The thickness of the charge transport layer is 5 to 5
It is preferably about 0 μm. Especially when high resolution is required, it is preferable that the film thickness of the charge transport layer is 20 μm or less, and thinning of the charge transport layer is most effective for improving the resolution.

As the solvent used for forming the charge transport layer, tetrahydrofuran, dioxane, toluene, dichloromethane, monochlorobenzene, dichloroethane, cyclohexanone, methyl ethyl ketone, acetone or the like is used.

Further, the charge transport layer may contain a polymer having an electron donating group. A polymer having an electron-donating group means a polymer charge-transporting substance having a function as a charge-transporting substance and a binder resin, or a state of a monomer or an oligomer having an electron-donating group at the time of forming a charge-transporting layer. Then, a polymer having a two-dimensional or three-dimensional crosslinked structure is finally included by carrying out a curing reaction or a crosslinking reaction after the film formation.

The charge transport layer composed of these polymer charge transport materials or the polymer having a crosslinked structure has excellent abrasion resistance. Usually, in the electrophotographic process, the charging potential (potential of unexposed portion) is constant, and therefore, when the surface layer of the photoconductor is worn by repeated use, the electric field strength applied to the photoconductor is correspondingly increased. As the electric field strength increases, the frequency of occurrence of scumming increases, and thus the high wear resistance of the photoconductor is advantageous for scumming. This tendency is particularly remarkable when the anodized film of the present invention is included.

Known materials can be used as the polymer charge transporting material, and polycarbonate having a triarylamine structure in its main chain and / or side chain is preferably used. Examples of the polycarbonate containing a triarylamine structure in the main chain and / or the side chain include the following.

[0063]

[Chemical 7] Where R₁, R₂, R₃Are each independently replaced or
Unsubstituted alkyl group or halogen atom, R_FourIs a hydrogen atom
Or a substituted or unsubstituted alkyl group, R_Five, R ₆Is replaced
Alternatively, an unsubstituted aryl group, o, p, and q are each independently.
Standing, an integer of 0 to 4, k and j represent compositions, and 0.1 ≦ k
≦ 1, 0 ≦ j ≦ 0.9, n represents the number of repeating units
It is an integer of 5000. X is an aliphatic divalent group, a cyclic fat
Represents a divalent group of the group or a divalent group represented by the following general formula
You

[Chemical 8] In the formula, R ₁₀₁ and R ₁₀₂ each independently represent a substituted or unsubstituted alkyl group, aryl group or halogen atom.
l and m are integers from 0 to 4, Y is a single bond, and has 1 to 1 carbon atoms.
2, a linear, branched or cyclic alkylene group, -O
-, - S -, - SO -, - SO 2 -, - CO -, - CO
-O-Z-O-CO- (in the formula, Z represents an aliphatic divalent group), or

[Chemical 9] (In the formula, a represents an integer of 1 to 20, b represents an integer of 1 to 2000, and R ₁₀₃ and R ₁₀₄ represent a substituted or unsubstituted alkyl group or aryl group.). Here, R ₁₀₁ and R _{1 02,}
R ₁₀₃ and R ₁₀₄ may be the same or different.

[0064]

[Chemical 10] In the formula, R ₇ and R ₈ are substituted or unsubstituted aryl groups, A
r ₁ , Ar ₂ and Ar ₃ represent the same or different arylene groups. X, k, j and n are the same as in the case of the formula (III).

[0065]

[Chemical 11] In the formula, R ₉ and R ₁₀ are substituted or unsubstituted aryl groups,
Ar ₄ , Ar ₅ and Ar ₆ represent the same or different arylene groups. X, k, j and n are the same as in the case of the formula (III).

[0066]

[Chemical 12] In the formula, R ₁₁ and R ₁₂ are substituted or unsubstituted aryl groups,
Ar ₇ , Ar ₈ and Ar ₉ are the same or different arylene groups, p
Represents an integer of 1 to 5. X, k, j and n are (II
It is the same as in the case of formula I).

[0067]

[Chemical 13] Where R₁₃, R₁₄Is a substituted or unsubstituted aryl group,
Ar_Ten, Ar₁₁, Ar ₁₂Are the same or different arylene groups,
X₁, X₂Is a substituted or unsubstituted ethylene group, or substituted
Alternatively, it represents an unsubstituted vinylene group. X, k, j and
n is the same as in the case of the formula (III).

[0068]

[Chemical 14] In the formula, R ₁₅ , R ₁₆ , R ₁₇ and R ₁₈ are substituted or unsubstituted aryl groups, Ar ₁₃ , Ar ₁₄ , Ar ₁₅ and Ar ₁₆ are the same or different arylene groups, and Y ₁ , Y ₂ and Y ₃ are They represent a single bond, a substituted or unsubstituted alkylene group, a substituted or unsubstituted cycloalkylene group, a substituted or unsubstituted alkylene ether group, an oxygen atom, a sulfur atom or a vinylene group and may be the same or different. X, k, j and n are
This is the same as the case of the formula (III).

[0069]

[Chemical 15] In the formula, R ₁₉ and R _{20 each} represent a hydrogen atom or a substituted or unsubstituted aryl group, and R ₁₉ and R ₂₀ may form a ring. Ar ₁₇ , Ar ₁₈ and Ar ₁₉ represent the same or different arylene groups. X, k, j and n are the same as in the case of the formula (III).

[0070]

[Chemical 16] In the formula, R ₂₁ is a substituted or unsubstituted aryl group, A ₂₁
r ₂₀ , Ar ₂₁ , Ar ₂₂ , and Ar ₂₃ represent the same or different arylene groups. X, k, j and n are the same as in the case of the formula (III).

[0071]

[Chemical 17] In the formula, R ₂₂ , R ₂₃ , R ₂₄ and R ₂₅ are substituted or unsubstituted aryl groups, Ar ₂₄ , Ar ₂₅ , Ar ₂₆ , Ar ₂₇ and Ar _28.
Represent the same or different arylene groups. X, k, j and n are the same as in the case of the formula (III).

[0072]

[Chemical 18] Where R₂₆, R₂₇Is a substituted or unsubstituted aryl group,
Ar₂₉, Ar₃₀, Ar ₃₁Are the same or different arylene groups
Represent X, k, j and n are the same as in the case of formula (III)
Is.

These polymeric charge transport materials may be used alone, or may be used as a mixture of two or more kinds with other polymeric charge transport materials. It is also possible to use a low molecular charge transport material together.

Other polymers having electron-donating groups include known monomer copolymers, block polymers, graft polymers and star polymers, and, for example, JP-A-3-109406. Japanese Patent Laid-Open No. 2000-206723
It is also possible to use a cross-linked polymer having an electron donating group as disclosed in JP-A No. 2001-34001 and the like.

In the photoconductor of the present invention, a plasticizer or a leveling agent may be added to the charge transport layer 37. As the plasticizer, those used as plasticizers for general resins such as dibutyl phthalate and dioctyl phthalate can be used as they are, and the amount thereof is 0 to 30 relative to the binder resin.
About wt% is appropriate. As the leveling agent, silicone oils such as dimethyl silicone oil and methylphenyl silicone oil, and polymers or oligomers having a perfluoroalkyl group in the side chain are used, and the amount thereof is 0 to 1 relative to the binder resin. Weight percent is suitable.

In the photoreceptor of the present invention, an undercoat layer can be provided between the anodized film 33 and the photosensitive layer (charge generation layer or charge transport layer). The subbing layer generally contains a resin as a main component, but considering that the photosensitive layer is coated on the resin with a solvent, the resin may be a resin having high solvent resistance to a general organic solvent. desirable. Such resins include polyvinyl alcohol, casein,
Water-soluble resin such as sodium polyacrylate, copolymer nylon, alcohol-soluble resin such as methoxymethylated nylon, polyurethane, melamine resin, phenol resin,
Examples include alkyd-melamine resins, epoxy resins, and other curable resins that form a three-dimensional network structure. Further, in order to prevent moire and reduce the residual potential, a fine powder pigment of a metal oxide such as titanium oxide, silica, alumina, zirconium oxide, tin oxide or indium oxide may be added to the undercoat layer.

These undercoat layers can be formed by using an appropriate solvent and coating method as in the above-mentioned photosensitive layer. Further, a silane coupling agent, a titanium coupling agent, a chromium coupling agent or the like can be used as the undercoat layer of the present invention. In addition, the undercoat layer of the present invention may be formed of Al ₂
O ₃ provided by anodic oxidation, organic substances such as polyparaxylylene (parylene), SiO ₂ , SnO ₂ , Ti
An inorganic substance such as O ₂ , ITO or CeO ₂ provided by a vacuum thin film forming method can also be favorably used. Besides these, known ones can be used. The thickness of the undercoat layer is 0 to 5 μm
Is appropriate.

In the photoreceptor of the present invention, a protective layer may be provided on the photosensitive layer for the purpose of protecting the photosensitive layer (charge generation layer or charge transport layer). Materials used for the protective layer include ABS resin, ACS resin, olefin-vinyl monomer copolymer, chlorinated polyether, allyl resin, phenol resin, polyacetal, polyamide, polyamideimide, polyacrylate, polyallyl sulfone, polybutylene, Polybutylene terephthalate, polycarbonate, polyether sulfone, polyethylene,
Examples thereof include resins such as polyethylene terephthalate, polyimide, acrylic resin, polymethylpentene, polypropylene, polyphenylene oxide, polysulfone, polystyrene, AS resin, butadiene-styrene copolymer, polyurethane, polyvinyl chloride, polyvinylidene chloride and epoxy resin. As a method for forming the protective layer, a usual coating method is adopted. The thickness of the protective layer is 0.1 to 10 μm.
The degree is appropriate. In addition to the above, known materials such as aC and a-SiC formed by the vacuum thin film forming method can be used as the protective layer.

In particular, when a protective layer is provided and a high resolution is required, the total thickness of the photosensitive layer and the protective layer is preferably 20 μm or less. To improve the resolution, a thin film having this total thickness is used. Is most effective.

A charge-transporting substance can be used for the protective layer, which is an effective means from the standpoint of suppressing an increase in residual potential due to stacking the protective layers. As the charge transport material, the materials mentioned in the description of the charge transport layer can be used. Regarding the proper use of the hole transporting material and the electron transporting material, it is preferable to select appropriately depending on the polarity of charging and the layer structure. Further, as the charge-transporting substance, the above-described polymer charge-transporting substance and the polymer having an electron-donating group can also be used.

In addition, a filler may be added to the protective layer for the purpose of improving abrasion resistance. Organic filler
Examples of the material include fluororesin powder such as polytetrafluoroethylene, silicone resin powder, and a-carbon powder, and examples of the inorganic filler material include metals such as copper, tin, aluminum and indium. Powder, silica, tin oxide, zinc oxide, titanium oxide, indium oxide,
Examples thereof include antimony oxide, bismuth oxide, tin oxide doped with antimony, metal oxides such as indium oxide doped with tin, and inorganic materials such as potassium titanate. In particular, from the viewpoint of the hardness of the filler, it is advantageous to use the inorganic material among them. In particular, silica, titanium oxide,
Alumina can be effectively used.

The average primary particle size of the filler is 0.0
The thickness is preferably 1 to 0.5 μm from the viewpoint of wear resistance of the protective layer. When the average primary particle diameter of the filler is 0.01 μm or less, abrasion resistance and dispersibility are deteriorated, and when it is 0.5 μm or more, sedimentation of the filler in the dispersion is promoted. The toner filming may occur.

The higher the filler material concentration in the protective layer is, the better the abrasion resistance is. Therefore, when it is too high, side effects such as increase in residual potential may occur. Therefore,
Approximately 50% by weight or less, preferably 3 based on the total solid content
It is about 0% by weight or less.

In the photoreceptor of the present invention, it is possible to provide an intermediate layer between the photosensitive layer and the protective layer. A binder resin is generally used as a main component in the intermediate layer. Examples of these resins include polyamide, alcohol-soluble nylon, water-soluble polyvinyl butyral, polyvinyl butyral, and polyvinyl alcohol. As a method of forming the intermediate layer, a usual coating method is adopted as described above. The thickness of the intermediate layer is preferably about 0.05 to 2 μm.

Further, in the present invention, in order to improve the environment resistance, in particular, to prevent the sensitivity from lowering and the residual potential from rising, each layer is provided with an antioxidant, a plasticizer, a lubricant, an ultraviolet absorber and a low molecular weight compound. Charge transport materials and leveling agents can be added. Representative materials for these compounds are described below.

Examples of the antioxidant that can be added to each layer include, but are not limited to, the followings.

(A) Phenol compound 2,6-di-t-butyl-p-cresol, butylated hydroxyanisole, 2,6-di-t-butyl-4-ethylphenol, n-octadecyl -3- (4'-hydroxy-3 ', 5'-di-t-butylphenol),
2,2'-methylene-bis- (4-methyl-6-t-butylphenol), 2,2'-methylene-bis- (4-
Ethyl-6-t-butylphenol), 4,4'-thiobis- (3-methyl-6-t-butylphenol),
4,4'-butylidene bis- (3-methyl-6-t-butylphenol), 1,1,3-tris- (2-methyl-4-hydroxy-5-t-butylphenyl) butane,
1,3,5-Trimethyl-2,4,6-tris (3,5
-Di-t-butyl-4-hydroxybenzyl) benzene, tetrakis- [methylene-3- (3 ', 5'-di-
t-butyl-4'-hydroxyphenyl) propionate] methane, bis [3,3'-bis (4'-hydroxy-3'-t-butylphenyl) butyric acid] glycol ester, tocopherols and the like.

(B) Para-phenylenediamines N-phenyl-N'-isopropyl-p-phenylenediamine, N, N'-di-sec-butyl-p-phenylenediamine, N-phenyl-N-sec-butyl- p-
Phenylenediamine, N, N'-di-isopropyl-p
-Phenylenediamine, N, N'-dimethyl-N, N '
-Di-t-butyl-p-phenylenediamine and the like.

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

(D) Organic Sulfur Compounds Dilauryl-3,3'-thiodipropionate, distearyl-3,3'-thiodipropionate, ditetradecyl-3,3'-thiodipropionate and the like.

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

Examples of the plasticizer that can be added to each layer include, but are not limited to, the following.

(A) Phosphate ester plasticizer triphenyl phosphate, tricresyl phosphate, trioctyl phosphate, octyl diphenyl phosphate, trichloroethyl phosphate, cresyl diphenyl phosphate, tributyl phosphate, tri-2 phosphate -Ethylhexyl, triphenyl phosphate and the like.

(B) Phthalate ester type plasticizers dimethyl phthalate, diethyl phthalate, diisobutyl phthalate, dibutyl phthalate, diheptyl phthalate, di-2-ethylhexyl phthalate, diisooctyl phthalate, di-n-phthalate. Octyl, dinonyl phthalate, diisononyl phthalate, diisodecyl phthalate, diundecyl phthalate, ditridecyl phthalate, dicyclohexyl phthalate, butylbenzyl phthalate, butyllauryl phthalate, methyloleyl phthalate, octyldecyl phthalate, dibutyl fumarate, Dioctyl fumarate etc.

(C) Aromatic Carboxylate Plasticizers Trioctyl trimellitate, Tri-n trimellitate
-Octyl, octyl oxybenzoate and the like.

(D) Aliphatic dibasic acid ester-based plasticizer dibutyl adipate, di-n-hexyl adipate, di-2-ethylhexyl adipate, di-n-adipate
Octyl, adipic acid-n-octyl-n-decyl, diisodecyl adipate, dicapryl adipate, di-2-ethylhexyl azelate, dimethyl sebacate,
Diethyl sebacate, dibutyl sebacate, di-n-octyl sebacate, di-2-ethylhexyl sebacate, di-2-ethoxyethyl sebacate, dioctyl succinate, diisodecyl succinate, dioctyl tetrahydrophthalate, dihydrotetrahydrophthalate -N-octyl and the like.

(E) Fatty acid ester derivative butyl oleate, glycerin monooleate, methyl acetylricinoleate, pentaerythritol ester, dipentaerythritol hexaester,
Triacetin, tributyrin, etc.

(F) Oxyacid ester type plasticizer Methyl acetylricinoleate, butyl acetylricinoleate, butylphthalylbutyl glycolate, tributyl acetylcitrate and the like.

(G) Epoxy plasticizer Epoxidized soybean oil, epoxidized linseed oil, epoxy butyl stearate, decyl epoxy stearate, octyl epoxy stearate, benzyl epoxy stearate, dioctyl epoxy hexahydrophthalate, epoxy hexahydrophthalate Didecyl acid etc.

(H) Dihydric alcohol ester plasticizers such as diethylene glycol dibenzoate and triethylene glycol di-2-ethylbutyrate.

(I) Chlorine-containing plasticizer Chlorinated paraffin, chlorinated diphenyl, chlorinated fatty acid methyl, methoxychlorinated fatty acid methyl and the like.

(J) Polyester Plasticizer Polypropylene adipate, polypropylene sebacate, polyester, acetylated polyester and the like.

(K) Sulfonic acid derivative p-toluene sulfonamide, o-toluene sulfonamide, p-toluene sulfone ethylamide, o-toluene sulfone ethylamide, toluene sulfone-N-ethylamide, p-toluene sulfone-N-cyclohexyl Amide etc.

(L) Citric Acid Derivatives Triethyl citrate, triethyl acetyl citrate, tributyl citrate, tributyl acetyl citrate, tri-2-ethylhexyl acetyl citrate, -n-octyl decyl acetyl citrate and the like.

(M) Other terphenyls, partially hydrogenated terphenyls, camphor, 2
-Nitrodiphenyl, dinonylnaphthalene, methyl abietate and the like.

Examples of the lubricant that can be added to each layer include, but are not limited to, the followings.

(A) Hydrocarbon compounds Liquid paraffin, paraffin wax, microwax, low-polymerization polyethylene, etc.

(B) Fatty acid compounds Lauric acid, myristic acid, palmitic acid, stearic acid, arachidic acid, behenic acid, etc.

(C) Fatty acid amide compounds Stearyl amide, palmityl amide, olein amide, methylene bis stearamide, ethylene bis stearamide, etc.

(D) Ester-based compound Lower alcohol ester of fatty acid, polyhydric alcohol ester of fatty acid, fatty acid polyglycol ester and the like.

(E) Alcohol type compounds Cetyl alcohol, stearyl alcohol, ethylene glycol, polyethylene glycol, polyglycerol and the like.

(F) Metal soap Lead stearate, cadmium stearate, barium stearate, calcium stearate, zinc stearate, magnesium stearate and the like.

(G) Natural waxes Carnauba wax, candelilla wax, beeswax, whale wax, ivorot wax, montan wax and the like.

(H) Other Silicone compounds, fluorine compounds, etc.

Next, the process of charging and exposing or only charging in the present invention (hereinafter referred to as corona treatment. However, as will be described later, the charging process targeted by the present invention is not limited to corona charging). . There are roughly two methods of corona treatment. One is a method of performing both charging and exposure, and the other is a method of performing only charging.

First, a method of using both corona charging and exposure will be described. This method is a method of applying charging and exposure to the photoconductor, and is performed by an apparatus as shown in FIG. In this case, in FIG. 4, one charger and one exposure device are provided for each photoconductor, but a plurality of chargers and exposure devices may be provided for the purpose of improving efficiency.

As the charger used here, known means such as a corotron, a scorotron, a solid state charger (solid state charger) and a charging roller can be used. Among them, the contact method or the method using a charging member arranged in close proximity (the surface of the photoconductor and the surface of the charger are about 200 μm or less) has a high charging efficiency, and the reactive gas (ozone or NOx) generated from the charger is high. It is used satisfactorily because it rarely occurs and it causes less chemical damage to the photoreceptor. In particular, the roller-shaped charging member is
Even when it is used in the contact method or in the close arrangement, there is no problem of positional accuracy and it is easy to handle, so that it can be used favorably.

The above-mentioned charging member arranged in close proximity means that the surface of the charging member is 10 to 200 μm with respect to the surface of the photosensitive member.
It is arranged close to a distance of about m, and any method may be used for the arrangement. For example, a charging member (roller) is mechanically supported at both ends so that it can be arranged close to the surface of the photoconductor, or a gap material is provided at a portion of the charging roller corresponding to the non-photoconductor image forming area. A mechanism for bringing only this portion into contact with the non-image forming area so that the image forming area of the photoconductor has a proper gap on the surface of the charging member also belongs to this category.

The photoconductor is charged by the charger, and the polarity of the applied charge is the same as that of the photoconductor. That is, in the case of a hole transport type photoreceptor, a negative polarity is applied as the surface charge, and in the case of an electron transport type photoreceptor, a positive polarity is applied as the surface charge. At this time, the electric field strength applied to the photoconductor is important, and it is desirable that the absolute value is 6 V / μm or more and 100 V / μm or less. 6V /
If it is less than μm, the effect of corona treatment is poor and 100V
If it is / μm or more, the photoreceptor may cause dielectric breakdown, which is not preferable.

As the exposure light source used in the present invention, a halogen lamp, a tungsten lamp, a fluorescent lamp, LD, L
Known means such as ED and EL can be used. In this corona treatment that uses both charging and exposure, electric charges flow in the film thickness direction of the photoconductor, so that the corona treatment can be performed more efficiently than the corona treatment method using only charging described below. However, this process may accelerate fatigue of the photoconductor at the same time, and it is important to set the exposure amount and the exposure wavelength to appropriate conditions. In particular, it is important to set the exposure wavelength according to the materials (charge generating substance, charge transporting substance) used for the photosensitive layer.

Next, the timing of performing the corona treatment will be described. What is important in the corona treatment is that the photoconductor of the present invention is mounted on the image forming apparatus and the corona treatment is completed before the first image is formed. Therefore, as long as the charge generation layer and the charge transport layer are formed and the drying and cooling steps are completed, the time may be before or after the mounting in the image forming apparatus.

If the image forming apparatus is not yet mounted, the process shown in FIG.
It is possible to perform the treatment with the corona treatment device having the structure shown in FIG. In this case, since the photoconductor is in the same state as it is mounted in the image forming apparatus before the shipment of the photoconductor,
Compared to the case of corona treatment in the image forming apparatus described later,
It has the advantage that the photoconductor after corona treatment can be inspected. Further, in the case of performing corona treatment in the image forming apparatus, if the corona treatment conditions of the apparatus and the image forming conditions do not match, a special program is separately required, which has a demerit of complicating the apparatus. Also,
Writing (or exposure) with the charging member in the image forming apparatus
Since members are used, there is also a demerit that those members are fatigued before image formation.
From the above, it is desirable to perform the corona treatment after coating the photoconductor and before mounting the photoconductor on the image forming apparatus, particularly before shipment from the factory.

When the image forming apparatus is installed, the corona treatment can be performed by using the charging member and the writing member (or the exposure member) installed in the image forming apparatus. In this case, the process is performed immediately after mounting the photoconductor, and is performed before the image formation of at least the first sheet.

The number of corona treatments will be described.
Since the corona treatment improves the barrier property of the anodized film on the photoreceptor, the object of the present invention can be achieved by performing the treatment at least once before it is used in the image forming apparatus. is there. Therefore, 1 before shipping
It only has to be performed once or once immediately after mounting the image forming apparatus. Of course, corona treatment may be carried out a plurality of times if necessary, but this is in the direction of fatigue of the photoreceptor,
It is more preferable to limit the number of treatments to the minimum.

The timing and the number of times of the corona treatment are applicable to both cases where charging and exposure are used together and cases where only charging is performed.

The following two methods can be mentioned as methods for selecting the exposure wavelength that does not cause fatigue of the photoconductor. One is to use only light having a longer wavelength side than the peak value on the longest wavelength side of the light absorption peak of the charge generating substance used for the photoconductor. FIG. 5 shows the relationship between the absorption spectrum of the charge generating substance and the exposure wavelength. “P” in FIG. 5 represents an absorption peak of the charge generating substance, and since there is one peak in the visible region to the near infrared region in this charge generating substance, the wavelength of “P” is the longest wavelength side. The absorption wavelength is used, and light with a shorter wavelength than this is not irradiated, but light with a longer wavelength than this is irradiated (FIG. 5). When there are a plurality of absorption peaks (P ₁ and P _{2 in} FIG. 6), light having a longer wavelength side than the absorption wavelength on the longest wavelength side (P _{2 in} FIG. 6) is irradiated. In addition, the absorption peak is a point in the absorption spectrum of the charge generating substance at which a certain point shows the maximum absorption, and at wavelengths on both sides thereof, the absorbance is smaller than the peak wavelength. Therefore, “S” in FIG. 5 is a shoulder and is not regarded as a peak.

As described above, a sharp cut filter, a bandpass filter, a near infrared cut filter, a dichroic filter, an interference filter, a color temperature conversion filter, etc. can be used to irradiate only a desired wavelength range.

The fact that the photoreceptor is less fatigued by the corona treatment in the present invention due to the light irradiation on the longer wavelength side than the absorption peak on the longest wavelength side of the charge generating substance is considered as follows. It In a photoreceptor using an organic substance, photocarriers are generated through the lowest excited state of the charge generating substance. This can be inferred from the fact that the carrier generation efficiency of the organic photoreceptor does not depend on the exposure wavelength. The difference between the energy level of the lowest excited state and the energy level of the ground state is almost equal to the value obtained by converting the absorption peak wavelength on the longest wavelength side of the charge generating substance into energy units (not exactly the same). When the photoconductor is irradiated with light having a wavelength shorter than the peak wavelength, the charge generating substance is excited to a higher level excited state (higher excited state) than the lowest excited state. The charge generating substance in the higher excited state releases energy in some form and relaxes to the lowest excited state, and photocarriers are generated from this state. Therefore, when an energy larger than the energy that can be excited to the lowest excited state is given, this energy is consumed as excess energy in the photoconductor. When this excess energy is relaxed, various reactions may occur, and it is considered that reactions that promote fatigue of the photoconductor may also occur at the same time. For this reason, the corona treatment is performed by irradiating the photoconductor with light that does not have excess energy (on the longer wavelength side than the absorption peak on the longest wavelength side) to minimize the fatigue of the photoconductor. That is, the effect of the present invention is maximized.

Here, a method for measuring the absorption spectrum of the charge generating substance will be described. A substrate that is substantially transparent in the charge generation substance absorption region is used, and a film is formed thereon with the charge generation substance alone or with a binder resin. The absorption spectrum of this may be measured with a commercially available spectrophotometer. At this time, as the transparent support, it is preferable to use optically transparent plastics (however, solvent resistance is required when the film is formed by a wet method) and glasses. Further, when forming a film, it is desirable to use a coating liquid having the same formulation as that of the charge generation layer in the photoconductor and form the film in the same manner as the photoconductor. Further, when the layer containing the charge generating substance can be peeled off from the photoconductor, it can be used as a sample for measurement. For example, when the photosensitive layer has a laminated structure (charge generation layer + charge transport layer), a sample (charge generation layer + charge transport layer) is obtained by peeling the photosensitive layer. Usually, the charge transport material (charge transport layer) does not have absorption in the absorption wavelength region of the charge generation material (may absorb part of the short wavelength component), so the absorption spectrum of this sample shows The absorption spectrum at least on the long wavelength side of the charge generating substance can be definitely obtained by almost reflecting the absorption spectrum. Further, it can be obtained from the spectral reflection spectrum of the photoconductor. As described above, the charge transport material (charge transport layer) does not absorb light in the absorption wavelength region of the charge generation material (may absorb part of the short wavelength component), so that light from the surface side of the photoconductor may be absorbed. The spectral reflection spectrum obtained by irradiating with the light and capturing the reflected light with a spectrophotometer reflects the absorption spectrum of the charge generating substance. As long as the support and the intermediate layer used as necessary have no large absorption that overlaps with the absorption of the charge-generating substance, the measurement can be performed by this method.

As another method, the absorption spectrum of the charge state of the charge transport material used for the photoconductor is
To identify. That is, when the irradiation light has an emission peak, it has a wavelength different from the absorption peak of the charged state, has a threshold value, and when it has an emission component at a wavelength longer than the threshold value, the threshold half-value wavelength is The wavelength is longer than the longest absorption peak wavelength of the charge state of the charge transport material,
In the case of having a threshold value and having a light emitting component at a wavelength shorter than the threshold value, the threshold half-value wavelength is shorter than the shortest absorption peak wavelength of the charge state of the charge transporting substance, whichever is satisfied. is important.

Next, the relationship between the irradiation light to the photoconductor and the absorption light in the charged state of the charge transport material will be described. Irradiation light to the photoreceptor used in the corona treatment of the present invention,
Basically, it must contain a light component in a wavelength range absorbed by the charge-generating substance in the photosensitive layer (otherwise, no photocarrier is generated). However, in many cases, the charge transport material absorbs light in the visible to near infrared region in the charged state, and may partially overlap with the light absorption wavelength of the charge generating material. Therefore,
It is practically impossible to allow the charge transport material in the charged state not to absorb the light at all, but to allow the charge generating material to absorb the light. Therefore, in the present invention, a light irradiation method is provided in which the amount of light absorbed in the charge state of the charge transport material is reduced or does not absorb light as much as possible, and in the corona treatment of the present invention, the fatigue of the photoreceptor is reduced as much as possible, and the corona treatment is performed. Is to maximize the effect of. Needless to say, when there is no overlapping portion, it is best to irradiate light in that wavelength range.

FIG. 7 shows the absorption state of the charge state of the charge transport material.
It is a figure which shows a vector typically. Two absorption peaks
Wavelength λ_AAnd λ_BIt is in. Fig. 8 shows the scanning of the light that illuminates the photoconductor.
The spectrum area is shown schematically. Of the irradiation light intensity
Peak value (Imax) half value (Imax / 2)
The short wavelength side is λ₁, The long wavelength side is λ₂And The invention
In the Rona treatment method, using the light shown in FIG.
Photoirradiation of a photoreceptor using the charge transport material shown in FIG.
Λ₂≤ λ_A, Λ₁≧ λ_AAnd λ ₂≤
λ_B, Λ₁≧ λ_BIrradiate in any relation
And good results are obtained.

FIG. 9 schematically shows an irradiation light spectrum region having a threshold wavelength. Half value (I) of the threshold value (Is) of light intensity
s / 2) The wavelength is λ ₃ . When light is irradiated to the photoreceptor using the charge transport material having the absorption spectrum of the charge state shown in FIG. 7 by using the light of FIG. 9, the relationship of λ ₃ ≧ λ _B is satisfied in the electrophotographic method of the present invention. Good results are obtained by holding and irradiating with light. Note that when the continuous light is the same and the light emission component is on the shorter wavelength side than the threshold value contrary to FIG. 9, the method of irradiating light in the relationship of λ ₃ ≧ λ _A is the present invention, and is preferable. The result is obtained.

On the other hand, as described above, the charge transfer in the charged state is performed.
As the material to be sent, it does not reduce the irradiation light quantity to the charge generating material.
In addition, better results are obtained when light is not absorbed as much as possible.
It Such a light irradiation method uses a light half-value width (λ₂−
λ₁) Is small, for example, when the
Can be revealed. FIG. 10 shows a charge transport material similar to that of FIG.
Half-value λ of the absorption peak of the charge state of _A, Λ_BAnd λ_c, Λ_dBut
It is defined. The light shown in FIG. 8 is shown in FIG.
When irradiating the₂≤ λ_A, Λ₁≧ λ_BAnd
λ₂≤ λ_c, Λ₁≧ λ_dIn any relationship between
Shooting results in even better results than above.
It In addition, the light of FIG. 9 is absorbed by the charge state shown in FIG.
Illuminate a photoreceptor using a charge transport material with a spectrum.
Λ₃≧ λ_dIn the relationship of
A better relationship is obtained than in the above case. In addition,
The same continuous light, but with a wavelength shorter than the threshold, contrary to FIG.
If there is a light emitting component on the side, λ₃≧ λ_AIn relation to
The method of light irradiation is the present invention, and good results have been obtained.
It In addition, the fact that the absorbed light of the present invention is not substantially included means that
From the above-described conditions of FIGS. 8 and 9 for the charge state of the cargo-transporting substance
Exposure conditions that prevent further light absorption (for example, in FIG.
λ_BAnd λ_cThe coherent light at the wavelength of the minimum absorption between
)), And in this state, a better result is obtained.
You can get the fruit.

A method for measuring the light absorption spectrum of the charge transport material in the charged state will be described. The upper and lower surfaces of the photosensitive layer or the charge transport layer are sandwiched by two electrodes, and a voltage is applied between the electrodes to pass a dark current or a photocurrent while using a normal spectrophotometer to absorb transmitted light or reflected light. taking measurement.
In addition, another simple spectrum measuring method can be applied. That is, the charge transport material is dissolved in an organic solvent such as acetonitrile, methylene chloride or dimethylformamide together with an irrelevant salt (supporting electrolyte) such as tetraethylammonium perchlorate or tetrabutylammonium perchlorate, and then electrolyzed, The cation radical state or the anion radical state is set. In this case, when the charge transport material is a hole transport material, it is oxidized at the anode to a cation radical state, and when it is an electron transport material, it is reduced at the cathode to an anion radical state. This method is to measure the transmitted light absorption of a charge transport substance in a cation radical state or an anion radical state in a solution state using an ordinary spectrophotometer.

Next, a method of performing corona treatment only by charging will be described. This method is a method in which only charging is applied to the photoconductor, and is performed by an apparatus as shown in FIG. In this case, one charger is arranged for the photoconductor in FIG. 11, but a plurality of chargers may be arranged for the purpose of improving efficiency. As the charger used here, known means such as a corotron, a scorotron, a solid state charger (solid state charger), and a charging roller can be used. Among them, the contact method or the method using a charging member arranged in close proximity (the surface of the photoconductor and the surface of the charger are about 200 μm or less) has a high charging efficiency, and the reactive gas (ozone or NOx) generated from the charger is high. It is used satisfactorily because it rarely occurs and it causes less chemical damage to the photoreceptor. In particular, the roller-shaped charging member does not have a problem of positional accuracy and is easy to handle even when it is used in the contact method or the close arrangement, and thus can be favorably used. In consideration of using AC as the applied voltage, a roller-shaped charger is more desirable.
Incidentally, the charging members arranged in proximity are the same as those described above.

The photoconductor is charged by the charger, and the polarity of the applied charge is the same as that of the photoconductor. That is, in the case of a hole transport type photoreceptor, a negative polarity is applied as the surface charge, and in the case of an electron transport type photoreceptor, a positive polarity is applied as the surface charge. At this time, the electric field strength applied to the photoconductor is important, and it is desirable that the absolute value is 6 V / μm or more and 100 V / μm or less. 6V /
If it is less than μm, the effect of corona treatment is poor and 100V
If it is / μm or more, there is a possibility of causing dielectric breakdown of the photoreceptor, which is not preferable.

Further, although the above-mentioned charging is performed by using the DC component, it is more preferable to use the AC component in superposition in order to perform the corona treatment in the present invention more efficiently. As the AC component, the charge potential of the photosensitive member due to the DC component is centered and the peak to peak is 2
About kV or less is desirable. In the case of more than this, the damage to the photoconductor is too large, more than the effect of corona treatment,
Fatigue the photoconductor. When a plurality of chargers are used together, the AC component may be superimposed on all the chargers, but only one may be used.

Further, even if the treatment is terminated after the corona treatment while the surface of the photoconductor is charged, the electric charge is erased by the subsequent spontaneous discharge, but the possibility that dust or the like will be attached increases. It is desirable to keep the potential as close to 0V as possible. At this time, the charger having only the DC component controls the potential to 0V, and the charger having the AC component superposed is set to 0V as the DC component. By superposing the AC component around this, the potential can be canceled. . Also,
It is effective to perform the corona treatment only by charging and use the exposure only when the charging is canceled, and it is within the scope of the present invention.

Next, the electrophotographic method and the electrophotographic apparatus of the present invention will be described in detail. FIG. 12 is a schematic diagram for explaining the electrophotographic process and the electrophotographic apparatus of the present invention, and the following modified examples also belong to the category of the present invention. In FIG. 12, the photoreceptor 1 has an oxide film on a conductive support, and at least a charge generation layer and a charge transport layer are provided thereon, and is subjected to a specific corona treatment. Although the photosensitive member 1 has a drum shape, it may have a sheet shape or an endless belt shape. As the charging charger 3, the pre-transfer charger 7, the transfer charger 10, the separation charger 11, and the pre-cleaning charger 13, known means such as a corotron, a scorotron, a solid state charger (solid state charger), and a charging roller are used. To be As the charging member, one that is in contact with or placed close to the photoconductor is preferably used. Further, when the photoconductor is charged by the charging member, charging unevenness can be effectively reduced by charging the photoconductor with an electric field in which a direct current component and an alternating current component are superimposed on the charging member.

The above-mentioned charging device can be generally used as the transfer means, but it is effective to use a combination of a transfer charger and a separation charger as shown in FIG.

The light sources such as the image exposure unit 5 and the static elimination lamp 2 are fluorescent lamps, tungsten lamps, halogen lamps, mercury lamps, sodium lamps, light emitting diodes (LE).
D), semiconductor lasers (LD), electroluminescence (EL) and the like can be used in general.
Further, various filters such as a sharp cut filter, a bandpass filter, a near infrared cut filter, a dichroic filter, an interference filter, and a color temperature conversion filter can be used to irradiate only light in a desired wavelength range.

Such a light source or the like is provided with a transfer step using light irradiation in addition to the steps shown in FIG. 12, a charge eliminating step, a cleaning step, or a step of pre-exposure to irradiate the photoreceptor with light. .

The toner developed on the photoconductor 1 by the developing unit 6 is transferred to the transfer paper 9, but not all of the toner is transferred, and some toner remains on the photoconductor 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, and known cleaning brushes such as a fur brush and a magfur brush are used.

When the electrophotographic photosensitive member is positively (negatively) charged and imagewise exposed, a positive (negative) electrostatic latent image is formed on the surface of the photosensitive member. A negative image is obtained by developing this with a toner of positive (negative) polarity. The reversal development is thus performed. A known method is applied to the developing means, and a known method is used for the charge removing means.

FIG. 13 shows another example of the electrophotographic process according to the present invention. The photoconductor 21 has an oxide film on a conductive support, on which at least a charge generation layer and a charge transport layer are provided, and is subjected to a specific corona treatment. It is driven by the drive rollers 22a and 22b, charged by the charger 23, image exposure by the light source 24, reversal development (not shown), transfer using the charger 25, pre-cleaning exposure by the light source 26, cleaning by the brush 27, light source 28. The static elimination by is repeated. In FIG. 13, the photoconductor 21 (of course, the support is transparent in this case) is irradiated with light for pre-cleaning exposure from the support side.

The electrophotographic process illustrated above is an example of the embodiment of the present invention, and other embodiments are of course possible. For example, in FIG. 13, pre-cleaning exposure is carried out from the support side, but this may be carried out from the photosensitive layer side, or image exposure and discharge of static elimination light may be carried out from the support side. On the other hand, in the light irradiation step, image exposure, pre-cleaning exposure, and static elimination exposure are shown. In addition, pre-transfer exposure, pre-exposure for image exposure, and other known light irradiation steps are provided to expose the photoreceptor to light. Irradiation can also be performed.

The image forming means as described above may be fixedly incorporated in a copying machine, a facsimile machine or a printer, but may be incorporated in these machines in the form of a process cartridge. The process cartridge is one device (component) that contains a photosensitive member and at least one of a charging unit, an exposing unit, a reversal developing unit, a transfer unit, a cleaning unit, and a discharging unit at the same time. There are many shapes of process cartridges and the like, and as a general example, the one shown in FIG. 14 is given. The photoconductor 16 has a conductive support and an oxide film on the conductive support, on which at least a charge generation layer and a charge transport layer are provided, and is subjected to a specific corona treatment. .

[0149]

EXAMPLES Next, the present invention will be described in more detail by way of examples. However, the present invention is not limited to the following examples. In the examples, all parts are parts by weight.

Preparation Example of Photoreceptor 1: Length 340 mm, Diameter 3
A 0 mm aluminum cylinder (JIS1050) was used as a conductive support, this was subjected to the following anodic oxide film treatment, and a charge generation layer coating liquid and a charge transport layer coating liquid having the following compositions were sequentially formed to form a 0.3 μm film. A charge generating layer and a charge transporting layer having a thickness of 20 μm were formed to obtain a photoreceptor.

(Anodic oxide film treatment) The surface of the support is mirror-polished, degreased and washed with water, and then at a liquid temperature of 2
Immerse in an electrolytic bath of 0 ° C and 15 vol% sulfuric acid, electrolysis voltage 1
Anodized film treatment was performed at 5 V for 30 minutes. Further, after washing with water, sealing treatment was performed with a 7% nickel acetate aqueous solution (50 ° C.). Then, after washing with pure water, a support having a 6 μm anodic oxide film formed thereon was obtained.

[0152] (Charge generation layer coating liquid)     10 parts of bisazo pigment having the following structure

[Chemical 19] Polyvinyl butyral 2 parts 2-butanone 200 parts Cyclohexanone 400 parts

[0153] (Charge transport layer coating liquid)     7 parts charge transport material with the following structure

[Chemical 20] Z type polycarbonate 10 parts Methylene chloride 80 parts

The absorption spectrum of the charge generation layer of the photoconductor in Preparation Example 1 of the photoconductor was as shown in FIG. 15 (the peak on the longest wavelength side of the charge generation substance is 583 nm).

Photoreceptor Preparation Example 2: A photoreceptor was prepared in the same manner as in Photoreceptor Preparation Example 1 except that the anodic oxide coating treatment time was changed and the thickness of the anodic oxide coating was changed to 3 μm. did.

Photoreceptor Preparation Example 3: A photoreceptor was prepared in the same manner as in Photoreceptor Preparation Example 1 except that the anodic oxide coating treatment time was changed and the thickness of the anodic oxide coating was changed to 10 μm. did.

Photoreceptor Preparation Example 4 A photoreceptor was prepared in the same manner as in Photoreceptor Preparation Example 1 except that the anodic oxide coating treatment time was changed and the thickness of the anodic oxide coating was changed to 16 μm. did.

Photoreceptor Preparation Example 5: A photoreceptor was prepared in the same manner as in Photoreceptor Preparation Example 1 except that the charge transport layer coating liquid in Photoreceptor Preparation Example 1 was changed to the following composition.

[0159] (Charge transport layer coating liquid)     Polymer charge transport material with the following structure 10 parts

[Chemical 21] 80 parts of methylene chloride

Photoreceptor Preparation Example 6 The film thickness of the charge transport layer in Photoreceptor Preparation Example 1 was set to 18 μm, and a protective layer coating solution having the following composition was applied onto the charge transport layer to form a 2 μm protective layer. Then, a photoconductor was prepared.

[0161] (Protective layer coating liquid)     3 parts charge transport material with the following structure

[Chemical formula 22] Z type polycarbonate 10 parts Methylene chloride 80 parts

Photoreceptor Preparation Example 7: The film thickness of the charge transport layer in Photoreceptor Preparation Example 1 was set to 18 μm, and a protective layer coating solution having the following composition was applied onto the charge transport layer to form a 2 μm protective layer. Then, a photoconductor was prepared. Curing conditions: 130 ° C-1 hour (protective layer coating liquid) Tin oxide 270 parts Styrene-methyl methacrylate-2-hydroxyethyl methacrylate 100 parts (10/40/50 molar ratio) Acetone 710 parts Cellosolve acetate 730 parts Methyl isobutyl Ketone 160 parts Hardener (Sumijour HT: Sumitomo Bayer) 60 parts

Photoreceptor Preparation Example 8: The thickness of the charge transport layer in Photoreceptor Preparation Example 1 was set to 18 μm, and a protective layer coating solution having the following composition was applied onto the charge transport layer to form a 2 μm protective layer. Then, a photoconductor was prepared. (Protective layer coating liquid) Z-type polycarbonate 10 parts Charge transport material of the following structural formula 7 parts

[Chemical formula 23] Alumina fine particles 4 parts (specific resistance: 2.5 × 10 ¹² Ω · cm, average primary particle size: 0.3 μm) Tetrahydrofuran 400 parts Cyclohexanone 200 parts

Photoreceptor Preparation Example 9: A photoreceptor was prepared in the same manner as in Photoreceptor Preparation Example 1 except that the thickness of the charge transport layer in Photoreceptor Preparation Example 1 was changed to 25 μm.

Photoconductor Preparation Example 10: A photoconductor was prepared in the same manner as in Photoconductor Preparation Example 1 except that the thickness of the charge transport layer in Photoconductor Preparation Example 1 was changed to 15 μm.

Photoreceptor Preparation Example 11: A photoreceptor was prepared in the same manner as in Photoreceptor Preparation Example 8 except that the thickness of the charge transport layer in Photoreceptor Preparation Example 8 was changed to 23 μm.

Photoconductor Preparation Example 12: A photoconductor was prepared in the same manner as in Photoconductor Preparation Example 8 except that the thickness of the charge transport layer in Photoconductor Preparation Example 8 was 13 μm.

Photoreceptor Preparation Example 13: A photoreceptor was prepared in the same manner as in Photoreceptor Preparation Example 1 except that the charge generation layer coating liquid in Photoreceptor Preparation Example 1 was changed to the following composition. (Charge generation layer coating liquid) 10 parts of bisazo pigment having the following structure

[Chemical formula 24] Polyvinyl butyral 2 parts 2-butanone 200 parts Cyclohexanone 400 parts The absorption spectrum of the charge generation layer of the photoconductor in Photoreceptor Preparation Example 13 was as shown in FIG. 16 (the peak on the longest wavelength side of the charge generation substance is It is 583 nm.)

Photoconductor Preparation Example 14: A photoconductor was prepared in the same manner as in Photoconductor Preparation Example 1 except that the anodic oxide film treatment was not performed.

(Example 1) Photoreceptor Preparation The photoreceptor prepared in Preparation Example 1 was subjected to corona treatment under the following conditions in a corona treatment apparatus as shown in FIG. Corona treatment condition: Charging condition: The surface potential of the photoreceptor is −1000 V (50 V / μm) during the corona treatment by the scorotron charger.
Adjust to be. Exposure condition: Tungsten light (white). Processing time: 10 minutes.

(Example 2) Photoreceptor Preparation The photoreceptor prepared in Preparation Example 1 was subjected to corona treatment under the following conditions in a corona treatment device as shown in FIG. Corona treatment conditions: Charging conditions: Adjusted by a scorotron charger so that the surface potential of the photoreceptor during corona treatment becomes -1000V. Exposure condition: 660 nm LED. Processing time: 10 minutes.

(Example 3) Photoreceptor Preparation The photoreceptor prepared in Preparation Example 1 was subjected to corona treatment under the following conditions in a corona treatment device as shown in FIG. Corona treatment conditions: Charging conditions: Adjusted by a scorotron charger so that the surface potential of the photoreceptor during corona treatment becomes -1000V. Exposure condition: Short-cut filter (HOYA: R60) was used for tungsten light to cut light shorter than 600 nm. Processing time: 10 minutes.

(Example 4) Photoreceptor Preparation The photoreceptor prepared in Preparation Example 1 was subjected to corona treatment under the following conditions in a corona treatment device as shown in FIG. Corona treatment condition: Charging condition: Adjusted with a scorotron charger so that the surface potential of the photoreceptor during corona treatment is -100V (5V / μm). Exposure condition: 660 nm LED. Processing time: 10 minutes.

(Example 5) Photoreceptor Preparation The photoreceptor prepared in Preparation Example 1 was subjected to corona treatment under the following conditions in a corona treatment device as shown in FIG. Corona treatment condition: Charging condition: Adjusted with a scorotron charger so that the surface potential of the photoreceptor during corona treatment is −200 V (10 V / μm). Exposure condition: 660 nm LED. Processing time: 10 minutes.

(Example 6) Photoreceptor Preparation The photoreceptor prepared in Preparation Example 1 was subjected to corona treatment under the following conditions in a corona treatment device as shown in FIG. Corona treatment condition: Charging condition: The surface potential of the photoreceptor during corona treatment is -1800 V (90 V / μm) by a scorotron charger.
Adjust to be. Exposure condition: 660 nm LED. Processing time: 10 minutes.

(Example 7) Photoreceptor Preparation The photoreceptor prepared in Preparation Example 1 was subjected to corona treatment under the following conditions in a corona treatment device as shown in FIG. Corona treatment condition: Charging condition: The surface potential of the photosensitive member during the corona treatment is -2200V (110V / μ) by the scorotron charger.
Adjust to be m). Exposure condition: 660 nm LED. Processing time: 10 minutes.

(Example 8) The photoreceptor prepared in Preparation Example 1 was subjected to corona treatment under the following conditions in a corona treatment apparatus as shown in FIG. Corona treatment condition: Charging condition: Adjusted by a contact type charging roller so that the surface potential of the photoreceptor during corona treatment becomes −1000 V (applied voltage is DC only). Exposure condition: After a corona treatment for 10 minutes, an LED of 660 nm is irradiated as erase light. Processing time: 10 minutes

(Example 9) Photoreceptor Preparation The photoreceptor prepared in Preparation Example 1 was subjected to corona treatment under the following conditions in a corona treatment device as shown in FIG. Corona treatment conditions: Charging conditions: A contact type charging roller was used to adjust the surface potential of the photoreceptor during corona treatment to −1000V.
As the AC component, 2 kV was superimposed on the peak top peak. Exposure conditions: No exposure. At the end of the corona treatment, the DC application is terminated, the AC bias is set to 0 V, and the peak is
1.5 kV was superimposed on to peak so that the surface potential of the photoconductor was near 0V. Processing time: 10 minutes.

Example 10 The photoreceptor prepared in Preparation Example 1 was subjected to corona treatment under the following conditions in a corona treatment apparatus as shown in FIG. Corona treatment condition: Charging condition: Wrap 100 μm insulating tape around both ends,
The charging surface of the roller was adjusted so that the surface potential of the surface of the photosensitive member was −1000 V during the corona treatment by a charging roller arranged in close proximity to the surface of the photosensitive member so that the effective charging area of the roller was 100 μm. As the AC component, 2 kV was superimposed on the peak to peak. Exposure conditions: No exposure. At the end of the corona treatment, the DC application is terminated, the AC bias is set to 0 V, and the peak is
2 kV was superimposed at to peak, and the surface potential of the photosensitive member was set to near 0V.

(Example 11) The photoreceptor prepared in Example 2 was subjected to corona treatment under the same conditions as in Example 2.

Example 12 Photoreceptor Preparation The photoreceptor prepared in Example 3 was subjected to corona treatment under the same conditions as in Example 2.

(Example 13) The photoreceptor prepared in Example 4 was subjected to corona treatment under the same conditions as in Example 2.

Example 14 Photoreceptor Preparation The photoreceptor prepared in Preparation Example 5 was subjected to corona treatment under the same conditions as in Example 2.

Example 15 Photoreceptor Preparation The photoreceptor prepared in Preparation Example 6 was subjected to corona treatment under the same conditions as in Example 2.

Example 16 Photoreceptor Preparation The photoreceptor prepared in Example 7 was subjected to corona treatment under the same conditions as in Example 2.

Example 17 Photoreceptor Preparation The photoreceptor prepared in Example 8 was subjected to corona treatment under the same conditions as in Example 2.

(Example 18) Photoreceptor Preparation The photoreceptor prepared in Preparation Example 9 was subjected to corona treatment under the following conditions in a corona treatment device as shown in FIG. Corona treatment condition: Charging condition: The surface potential of the photoconductor during corona treatment is -1250 V (50 V / μm) by a scorotron charger.
Adjust to be. Exposure condition: 660 nm LED. Processing time: 10 minutes.

Example 19 The photoreceptor prepared in Preparation Example 10 was subjected to corona treatment under the following conditions in the corona treatment apparatus as shown in FIG. Corona treatment condition: Charging condition: Adjusted by a scorotron charger so that the surface potential of the photoreceptor during corona treatment becomes −750 V (50 V / μm). Exposure condition: 660 nm LED. Processing time: 10 minutes.

(Example 20) Photoreceptor Preparation The photoreceptor prepared in Preparation Example 11 was subjected to corona treatment under the following conditions in a corona treatment device as shown in FIG. Corona treatment condition: Charging condition: The surface potential of the photoconductor during corona treatment is -1250 V (50 V / μm) by a scorotron charger.
Adjust to be. Exposure condition: 660 nm LED. Processing time: 10 minutes.

(Example 21) Photoreceptor Photoreceptor prepared in Example 12 was treated with a corona treatment device as shown in FIG.
Corona treatment was performed under the following conditions. Corona treatment condition: Charging condition: Adjusted by a scorotron charger so that the surface potential of the photoreceptor during corona treatment becomes −750 V (50 V / μm). Exposure condition: 660 nm LED. Processing time: 10 minutes.

Example 22 Photoreceptor Preparation The photoreceptor prepared in Example 13 was subjected to corona treatment under the same conditions as in Example 2.

(Comparative Example 1) Photoreceptor The photoreceptor prepared in Preparation Example 1 was directly subjected to the following experiment without corona treatment.

(Comparative Example 2) The photoconductor prepared in Photoreceptor Preparation Example 2 was directly subjected to the following experiment without corona treatment.

(Comparative Example 3) Photoreceptor The photoreceptor prepared in Example 3 was directly subjected to the following experiment without corona treatment.

Comparative Example 4 Photoreceptor The photoreceptor prepared in Preparation Example 4 was directly subjected to the next experiment without corona treatment.

(Comparative Example 5) Photoreceptor Preparation The photoreceptor prepared in Preparation Example 5 was directly subjected to the next experiment without corona treatment.

(Comparative Example 6) Photoreceptor Preparation The photoreceptor prepared in Preparation Example 6 was directly subjected to the following experiment without corona treatment.

(Comparative Example 7) The photoconductor prepared in Photoreceptor Preparation Example 7 was directly subjected to the next experiment without corona treatment.

Comparative Example 8 The photoconductor prepared in Photoreceptor Preparation Example 8 was directly subjected to the following experiment without corona treatment.

(Comparative Example 9) Photoreceptor The photoreceptor prepared in Example 9 was directly subjected to the following experiment without corona treatment.

(Comparative Example 10) Photoreceptor Preparation The photoreceptor prepared in Preparation Example 10 was directly subjected to the following experiment without corona treatment.

(Comparative Example 11) Photoreceptor Preparation The photoreceptor prepared in Preparation Example 11 was directly subjected to the next experiment without corona treatment.

(Comparative Example 12) The photoreceptor prepared in Example 14 was subjected to corona treatment under the same conditions as in Example 2.

The above Examples 1 to 22 and Comparative Examples 1 to 1
The photoconductor of No. 2 was mounted on a process cartridge as shown in FIG. 14, mounted on a copier (imagio MF2200 manufactured by Ricoh Co., Ltd.) whose writing light source was modified to 655 nm LD, and a running test of 10,000 sheets (continuous run) was performed. At this time, white solid images at the initial stage and after 10,000 sheets were output to evaluate the background stain level. Further, an electrometer was set in the developing section, a white solid image and a black solid image were output before use of the copying machine, and the image unexposed portion potential (VD) and the image exposed portion potential (VL) of the photoconductor were measured. . The results are shown in Tables 1 and 2. The background stain rank in the table represents the level of background stain in stages, and the larger the number, the better. Evaluation was made on a scale of 5 with a maximum of 5 and a minimum of 1. Ranks 2 and below are levels that cannot withstand actual use.

[0205]

[Table 1]

[0206]

[Table 2]

From Tables 1 and 2, it can be seen that when the corona treatment is not performed, the initial background stain is remarkable, and the corona treatment improves it. Further, it can be seen that when the electric field strength in the corona treatment is low, the effect is small, and when it is too high, the background stain is good, but black spots are generated due to the dielectric breakdown. Further, it can be seen that when the exposure in the corona treatment includes the absorption peak of the charge generating substance, the corona treatment may promote fatigue of the photoreceptor.

Examples 2, 14, 15, 16, 17, 2
With respect to the photoreceptors 0 and 21, the amount of wear was measured in a running test of 10,000 sheets. The results are shown in Table 3.

[0209]

[Table 3]

From Table 3, it can be seen that when the protective layer is provided on the surface of the photoconductor, the wear amount of the photoconductor is significantly reduced.

Using the photoconductors of Examples 2, 8, 9 and 10,
Immediately after the corona treatment, a halftone image was output by the copying machine under the environment of 30 ° C.-90% RH. As a result, the photoconductors of Examples 8, 9 and 10 output quite normal images, but the photoconductor of Example 2 has a slight image deletion although it is at a level where there is no problem in practical use. occured.

Examples 2, 17, 18, 19, 20, 21
25 ° C-55% R immediately after corona treatment using the photoconductor
The resolution was evaluated under the H environment. The results are shown in Table 4.

[0213]

[Table 4]

From Table 4, it can be seen from the comparison of Examples 2, 18, and 19 that the thinner the charge transport layer, the better the resolution. The tendency is that the thickness of the charge transport layer is 20 μm.
The following is more remarkable. In addition, Examples 17 and 2
From the comparison of 0 and 21, it is understood that the smaller the film thickness of the charge transport layer + the protective layer, the better the resolution. This tendency is remarkable when the total thickness of both layers is 20 μm or less.

Photoreceptor Preparation Example 15: An aluminum cylinder (JIS1050) having a length of 334 mm and a diameter of 60 mm was used as a conductive support, and this was subjected to the following anodic oxide film treatment,
A charge generation layer coating liquid and a charge transport layer coating liquid having the following compositions were sequentially formed to form a 0.3 μm charge generation layer and a 20 μm charge transport layer to obtain a photoreceptor.

(Anodic oxide film treatment) The surface of the support was mirror-polished, degreased and washed with water, and then at a liquid temperature of 2
Immerse in an electrolytic bath of 0 ° C and 15 vol% sulfuric acid, electrolysis voltage 1
Anodized film treatment was performed at 5 V for 30 minutes. Further, after washing with water, sealing treatment was performed with a 7% nickel acetate aqueous solution (50 ° C.). Then, after washing with pure water, a support having a 7 μm anodic oxide film formed thereon was obtained.

[0217] (Charge generation layer coating liquid)     3 parts titanyl phthalocyanine having XD spectrum shown in FIG.     Polyvinyl butyral 2 parts     2-butanone 120 parts

[0218] (Charge transport layer coating liquid)     7 parts charge transport material with the following structure

[Chemical 25] C type polycarbonate 10 parts Methylene chloride 80 parts

The absorption spectrum of the charge-generating substance in Photoreceptor Preparation Example 15 was as shown in FIG. It can be seen that the absorption regions of the charge generating substance are in the ranges of 300 to 400 nm and 600 to 900 nm. Therefore, it is understood that the exposure in the corona treatment needs to include light in this range.

The absorption spectrum in the charged (cation radical) state of the charge transport material of Photoreceptor Preparation Example 15 was as shown in FIG. When the peak wavelength and the peak half-value wavelength shown in FIGS. 7 and 10 are obtained from FIG. 19, λ _A = 747 nm, λ _B = 952 nm, and λa = 4, respectively.
25 nm, λb = 554 nm, λc = 840 nm, λd
= 1025 nm. From this result, it can be seen that the region in which the absorption amount of the charge generating substance is large and the absorption amount of the charge transporting substance in the charged state is small is in the range of about 650 to 800 nm.

Photoconductor Preparation Example 16: A photoconductor was prepared in the same manner as in Photoconductor Preparation Example 15 except that the anodic oxide film treatment was not carried out.

Photosensitive member preparation example 17: In the photosensitive member preparation example 15, the undercoating layer coating solution having the following composition was applied on the conductive support without performing the anodic oxide film treatment to form a 2 μm undercoating layer. A photoconductor was produced in the same manner as in Photoconductor Production Example 15 except that (photoreceptor constitution was support / undercoat layer / charge generation layer /
The charge transport layer).

[0223] (Undercoat layer coating liquid)     Titanium oxide [TA-3000, manufactured by Fuji Titanium Industry] 57 parts     Alkyd resin [Beckolite M6805-40,       Made by Dainippon Ink and Chemicals, Inc.] (solid content 40%) 10 parts     Melamine resin [Super Beckamine G-821-60,       Made by Dainippon Ink and Chemicals, Inc.] (solid content 60%) 7 parts     100 parts of methyl ethyl ketone

Photoreceptor Preparation Example 18: The undercoat layer coating solution in Photoreceptor Preparation Example 17 was replaced with one having the following composition, and 0.2
A photoconductor was prepared in the same manner as in Photoconductor Preparation Example 17, except that the undercoat layer of μm was formed. (Undercoat layer coating liquid) Tributoxyzirconium acetylacetonate (ZC-540, manufactured by Matsumoto Kosho Co., Ltd.) 16.5 parts N (3-tributoxysilylpropyl) -1,6-hexylene dilena (KBM-6063, Shin-Etsu) Chemical industry) 10 parts Isopropyl alcohol 600 parts

Photoreceptor Preparation Example 19: The coating liquid for undercoat layer in Photoreceptor Preparation Example 17 was replaced with one having the following composition, and 0.2
A photoconductor was prepared in the same manner as in Photoconductor Preparation Example 17, except that the undercoat layer of μm was formed. (Undercoat layer coating liquid) Nylon resin (CM8000, manufactured by Toray) 10 parts Methanol 60 parts n-Butanol 32 parts

Photoconductor Preparation Example 20: A photoconductor was prepared in the same manner as in Photoconductor Preparation Example 15 except that the charge transporting material contained in the charge transport layer in Photoconductor Preparation Example 15 was changed to the following structure. (Charge transport material)

[Chemical formula 26]

The absorption spectrum in the charged (cation radical) state of the charge transport material of Photoreceptor Preparation Example 20 was as shown in FIG. When the peak wavelength and the peak half-value wavelength shown in FIGS. 7 and 10 are obtained from FIG. 20, λ _A = 358 nm and λ _B = 398 nm, respectively. Here, the half-value on the long wavelength side of λ _A overlaps with the absorption having a peak at λ _B , so that λ b = 439 nm (λ a cannot be displayed and λ c and λ d do not exist). From this result, the region where the absorption amount of the charge generating substance is large and the absorption amount of the charge transporting substance in the charged state is small is 600 to 900.
It can be seen that the range is about nm.

(Example 23) Photoreceptor Preparation The photoreceptor prepared in Preparation Example 15 was subjected to corona treatment under the following conditions in a corona treatment apparatus as shown in FIG. Corona treatment conditions: Charging conditions: A contact charging roller was used to adjust the surface potential of the photoreceptor during corona treatment to -800V. Exposure condition: Tungsten light (white) was combined with a short-cut filter (HOYA, R-60) and a long-wavelength cut filter (Asahi spectroscopy, No. 14) to irradiate light with a FWHM region of 610 to 710 nm. Processing time: 10 minutes

(Example 24) Photoreceptor Preparation The photoreceptor prepared in Preparation Example 15 was subjected to corona treatment under the following conditions in a corona treatment device as shown in FIG. Corona treatment conditions: Charging conditions: A contact charging roller was used to adjust the surface potential of the photoreceptor during corona treatment to -800V. Exposure condition: LD of 780 nm. Processing time: 10 minutes.

Example 25 Photoreceptor Preparation The photoreceptor prepared in Preparation Example 15 was subjected to corona treatment under the following conditions in a corona treatment device as shown in FIG. Corona treatment conditions: Charging conditions: A contact charging roller was used to adjust the surface potential of the photoreceptor during corona treatment to -800V. Exposure conditions: Tungsten light was combined with a shortcut filter (manufactured by HOYA, IR83) and a long-wavelength cut filter (manufactured by Asahi Bunko, 960 nm) to irradiate light having a half-value width region of 850 to 950 nm. Processing time: 10 minutes.

(Example 26) Photoreceptor Preparation The photoreceptor prepared in Preparation Example 20 was subjected to corona treatment under the following conditions in a corona treatment device as shown in FIG. Corona treatment conditions: Charging conditions: A contact charging roller was used to adjust the surface potential of the photoreceptor during corona treatment to -800V. Exposure conditions: Tungsten light was combined with a short-cut filter (HOYA, UV-36) and a long-wavelength cut filter (Asahi spectroscopy, No. 1) to irradiate light with a FWHM region of 380 to 440 nm. Processing time: 10 minutes.

(Example 27) Photoreceptor Preparation The photoreceptor prepared in Preparation Example 20 was subjected to corona treatment under the following conditions in a corona treatment device as shown in FIG. Corona treatment conditions: Charging conditions: A contact charging roller was used to adjust the surface potential of the photoreceptor during corona treatment to -800V. Exposure conditions: Tungsten light (white) was combined with a short-cut filter (HOYA, R-60) and a long-wavelength cut filter (Asahi spectroscopy, No. 14) to irradiate light with a half-width region of 610 to 710 nm. . Processing time: 10 minutes.

(Example 28) The photoconductor prepared in Photoreceptor Preparation Example 20 was subjected to a corona treatment apparatus as shown in FIG.
Corona treatment was performed under the following conditions. Corona treatment conditions: Charging conditions: A contact charging roller was used to adjust the surface potential of the photoreceptor during corona treatment to -800V. Exposure condition: a light emitting diode having an emission peak at 810 nm (half-emission of light emission is in the range of 790-830 nm). Processing time: 10 minutes.

(Comparative Example 13) The photoreceptor prepared in Preparation Example 16 was subjected to corona treatment in the same manner as in Example 23.

(Comparative Example 14) The photoreceptor prepared in Preparation Example 17 was subjected to corona treatment in the same manner as in Example 23.

(Comparative Example 15) The photoreceptor prepared in Preparation Example 18 was subjected to corona treatment in the same manner as in Example 23.

(Comparative Example 16) The photoreceptor prepared in Preparation Example 19 was subjected to corona treatment in the same manner as in Example 23.

(Comparative Example 17) Photoreceptor Preparation The photoreceptor prepared in Preparation Example 15 was subjected to the following experiment without corona treatment.

The above Examples 23 to 28 and Comparative Example 13
The photoconductors Nos. 17 to 17 are mounted on a process cartridge as shown in FIG. 14, and a copying machine (manufactured by Ricoh: imagio MF
4550), and a running test of 20,000 sheets (continuous run) was performed. At this time, white solid images at the initial stage and after 20,000 sheets were output to evaluate the background stain level.
Further, an electrometer was set in the developing section, a white solid image and a black solid image were output before use of the copying machine, and the image unexposed portion potential (VD) and the image exposed portion potential (VL) of the photoconductor were measured. . The results are shown in Table 4.

[0240]

[Table 5]

From Table 5, it can be seen that the initial background stain is remarkable when the corona treatment is not performed. Further, it can be seen that when the resin-based undercoat layer is used instead of the anodized film, the effect of preventing the background stain is low. Further, it can be seen that when the light in the absorption region of the charge state of the charge transport material used for the photoconductor is used for the exposure in the corona treatment, fatigue of the photoconductor may be promoted.

[0242]

As described above, according to the electrophotographic photoreceptor for reversal development of claim 1, in the reversal development photoreceptor having the anodized film, charging and charging are performed before the photoreceptor is used in the electrophotographic apparatus. Since the exposure process is performed, it is possible to obtain a photoconductor with less background stain from the initial state.

According to the electrophotographic photosensitive member for reversal development of claim 2, since the exposure wavelength in the charging and exposing process is selected and used in accordance with the physical properties of the charge generating substance used in the photosensitive member, Fatigue of the photoreceptor in the above processing can be suppressed to a minimum.

According to the electrophotographic photosensitive member for reversal development of claim 3, since the exposure wavelength in the charging and exposure processing is selected and used in accordance with the physical properties of the charge transport substance used in the photosensitive member, Fatigue of the photoreceptor in the above processing can be suppressed to a minimum.

According to the electrophotographic photoconductor for reversal development of claim 4, the reversal development photoconductor having the anodized film is subjected to a charging treatment before it is used in an electrophotographic apparatus. Similarly, from the initial state, it is possible to obtain a photoconductor with less background stain.

According to the electrophotographic photosensitive member for reversal development of claim 5, the voltage used in the charging process is an alternating electric field in which a DC voltage is superposed on an AC voltage. Therefore, the corona treatment in the present invention is more efficient. It is possible to do so.

According to the electrophotographic photosensitive member for reversal development of claim 6, since the absolute value of the electric field strength applied to the photosensitive member by the charging is 6 V / μm or more and 100 V / μm or less, the corona treatment effect is sufficient. In addition, the possibility of causing dielectric breakdown of the photoconductor is extremely reduced.

According to the electrophotographic photosensitive member for reversal development of claim 7, the photosensitive member is a cylindrical photosensitive member, and the charging process is performed by a contact charging member or a charging member arranged in proximity. High charging efficiency, less reactive gas generated from the charger, and less chemical damage to the photoconductor.

According to the electrophotographic photosensitive member for reversal development of claim 8, since the contact charging member or the charging member arranged in proximity is in the shape of a roller, there is no problem of positional accuracy and the handling is easy. Therefore, it can be used satisfactorily.

According to the electrophotographic photoreceptor for reversal development of claim 9, the thickness of the anodized film on the photoreceptor is 5 μm.
As described above, since the thickness is 15 μm or less, a barrier effect as an anodized film is sufficiently obtained, a residual potential is small, and a highly responsive photoreceptor is obtained.

According to the electrophotographic photoreceptor for reversal development of claim 10, since the outermost surface layer of the photoreceptor is a charge transport layer and the charge transport layer contains a polymer having an electron donating group, abrasion resistance is improved. Excellent in. In addition, since it is excellent in abrasion resistance, it is advantageous against ground stains, and this tendency is particularly remarkable when an anodized film is provided as in the present invention.

According to the electrophotographic photoreceptor for reversal development of claim 11, since the protective layer is provided on the outermost surface of the photoreceptor, not only the charge generation layer or the charge transport layer is protected but also the surface of the photoreceptor is protected. The wear resistance can be improved. In addition, since it is excellent in abrasion resistance, it is advantageous against ground stains, and this tendency is particularly remarkable when an anodized film is provided as in the present invention.

According to the electrophotographic photoreceptor for reversal development of claim 12, since the protective layer contains the low molecular charge transporting substance or the polymer having the electron donating property, the abrasion resistance of the surface of the photoreceptor is further improved. As described above, the present invention is particularly advantageous for suppressing the background stain.

According to the electrophotographic photosensitive member for reversal development of claim 13, since the protective layer contains a filler, the abrasion resistance and the background stain preventing effect can be further improved.

According to the electrophotographic photosensitive member for reversal development of claim 14, in the photosensitive member, the thickness of the photosensitive layer (when the protective layer is provided, the total thickness of the photosensitive layer and the protective layer) is 20.
Since it is at most μm, excellent resolution can be obtained.

According to the electrophotographic photosensitive member for reversal development of claim 15, the charge generating substance contained in the charge generating layer in the photosensitive member is an azo pigment represented by the formula (I). Easy to obtain high light sensitivity.

According to the electrophotographic photoreceptor for reversal development of Item 16, since the Cp ₁ and Cp ₂ of the azo pigments are different from each other, good photosensitivity can be obtained and the diameter of the photoreceptor can be reduced. It can respond to speeding up of the usage process and can be used effectively.

According to the electrophotographic photoreceptor for reversal development of claim 17, since the specific titanyl phthalocyanine is used as the charge generating substance, a photoreceptor having excellent photosensitivity can be obtained as in the case of the azo pigment. You can

According to the electrophotographic method of the eighteenth aspect, since at least charging, image exposure, reversal development and image transfer are repeated using the above-mentioned photoconductor, stable reversal with little background stain from the initial stage to the lapse of time. A developing type electrophotographic method can be provided.

According to the nineteenth aspect of the electrophotographic apparatus, since at least the photoconductor, the charging unit, the image exposing unit, the reversal developing unit and the transfer unit are provided, stable reversal with little background stain from the initial stage to the lapse of time is possible. A development type electrophotographic apparatus can be provided.

According to the process cartridge of claim 20, since the electrophotographic photosensitive member for reversal development is provided at least, the process cartridge for electrophotographic apparatus of the stable reversal development system with little background stain from the initial stage to the passage of time is provided. Can be provided.

[Brief description of drawings]

FIG. 1 is a schematic view showing a layer structure of an electrophotographic photosensitive member of the present invention.

FIG. 2 is a schematic diagram showing another configuration example of the electrophotographic photosensitive member of the present invention.

FIG. 3 is a schematic view showing still another configuration example of the electrophotographic photosensitive member of the present invention.

FIG. 4 is a schematic view of a corona treatment device used in the present invention.

FIG. 5 is a diagram showing a relationship between an absorption spectrum of a charge generating substance and an exposure wavelength.

FIG. 6 is a diagram showing a relationship between an absorption spectrum of a charge generating substance and an exposure wavelength (when there are a plurality of absorption peaks).

FIG. 7 is a diagram schematically showing an absorption spectrum of a charge transport substance in a charge state.

FIG. 8 is a diagram schematically showing a spectral range of light with which a photoconductor is irradiated.

FIG. 9 is a diagram schematically showing an irradiation light spectrum region having a threshold wavelength.

FIG. 10 is a diagram schematically showing an absorption spectrum of a charge transport substance in a charged state (defining half values of two absorption peaks).

FIG. 11 is a schematic view of a processing device used in the present invention, which performs only charging.

FIG. 12 is a schematic explanatory diagram of an electrophotographic process and an electrophotographic apparatus.

FIG. 13 is a schematic explanatory view showing another example of an electrophotographic process.

FIG. 14 is a schematic explanatory view showing an example of a process cartridge.

FIG. 15 is an absorption spectrum of a charge generation layer in a photoconductor preparation example.

FIG. 16 is an absorption spectrum of a charge generation layer in another example of forming a photoreceptor.

FIG. 17 is a spectral diagram of titanyl phthalocyanine having an XD spectrum.

FIG. 18 is an absorption spectrum of the charge generation layer in another example of forming a photoreceptor.

FIG. 19 is a charge-state absorption spectrum of a charge-transporting substance in a photoconductor preparation example.

FIG. 20 is a charge state absorption spectrum of a charge transport material of another example of preparing a photoreceptor.

[Explanation of symbols]

1 photoconductor Charger or charger 31 conductive support 33 Anodized film 35 Charge generation layer 37 Charge Transport Layer 39 Protective layer

Front page continuation (51) Int.Cl. ⁷ Identification code FI theme code (reference) G03G 5/147 504 G03G 5/147 504 15/02 15/02 101 101 15/08 502 15/08 502A 21/00 21 / 00 F term (reference) 2H068 AA19 AA52 BA15 BA39 BA43 EA05 EA43 2H077 GA03 GA17 2H134 QA02 2H200 FA02 GA14 GA16 GA23 GA28 GA35 GA44 GB50 HA03 HA11 HA28 HB12 HB22 LA38 NA06

Claims (20)

[Claims] 1. An electrophotographic photoreceptor for reversal development comprising a conductive support having an anodized film surface on which at least a charge generation layer and a charge transport layer are provided, wherein the charge generation layer and the charge transport layer are formed. An electrophotographic photosensitive member for reversal development, which is characterized in that after the photosensitive member is charged and exposed before being used in an electrophotographic apparatus. 2. The electrophotographic photosensitive member for reversal development according to claim 1, wherein in the exposure in the charging and exposure processing, the peak of the light absorption peak of the charge generating substance used in the photosensitive member is the longest wavelength side An electrophotographic photoreceptor for reversal development, characterized in that only light having a wavelength longer than the peak value is used. 3. The electrophotographic photosensitive member for reversal development according to claim 1, wherein a half-emission wavelength is used for the charge transport layer when the irradiation light has an emission peak for the exposure in the charging and exposure processing. When the wavelength is different from the absorption peak wavelength of the charge state of the charge transport material, and when the emission component has a threshold value and a wavelength longer than the threshold value, the threshold half value wavelength is greater than the longest absorption peak wavelength of the charge state of the charge transport material. Also has a long wavelength, and in the case of having a threshold value and having an emission component at a wavelength shorter than the threshold value, the threshold half value wavelength is shorter than the shortest absorption peak wavelength of the charge state of the charge transport material. An electrophotographic photoreceptor for reversal development. 4. An electrophotographic photoreceptor for reversal development comprising a conductive support having a surface anodized film-treated and provided with at least a charge generation layer and a charge transport layer, wherein the charge generation layer and the charge transport layer are formed. An electrophotographic photoconductor for reversal development, which is characterized in that after the photoconductor is used in an electrophotographic apparatus, a process of only charging is performed. 5. The electrophotographic photoreceptor for reversal development according to claim 4, wherein the voltage used in the charging process is an alternating electric field in which an alternating voltage is superimposed on a direct current voltage. Photoconductor. 6. The electrophotographic photosensitive member for reversal development according to claim 1, wherein an absolute value of an electric field strength applied to the photosensitive member by the charging is 6 V / μm or more, 100 or more.
An electrophotographic photosensitive member for reversal development, which has a V / μm or less. 7. The electrophotographic photosensitive member for reversal development according to claim 1, wherein the photosensitive member is a cylindrical photosensitive member, and the charging process is performed by a contact charging member or a proximity arrangement. An electrophotographic photosensitive member for reversal development, which is performed by a charging member. 8. The electrophotographic photoconductor for reversal development according to claim 7, wherein the contact charging member or the charging member disposed in proximity to the electrophotographic photoconductor has a roller shape. . 9. The electrophotographic photoreceptor for reversal development according to claim 1, wherein the anodic oxide film has a film thickness of 5 μm or more and 15 μm or less. Photoconductor. 10. The electrophotographic photoreceptor for reversal development according to claim 1, wherein the outermost surface layer of the photoreceptor is a charge transport layer, and the charge transport layer has an electron donating group. An electrophotographic photosensitive member for reversal development, which comprises: 11. The electrophotographic photoreceptor for reversal development according to claim 1, wherein a protective layer is provided on the outermost surface of the photoreceptor. 12. The electrophotographic photoreceptor for reversal development according to claim 11, wherein the protective layer contains a low molecular charge transporting substance or a polymer having an electron donating property. . 13. The electrophotographic photoreceptor for reversal development according to claim 11, wherein the protective layer contains a filler. 14. The electrophotographic photosensitive member for reversal development according to claim 1, wherein the photosensitive layer has a film thickness (when a protective layer is provided, the total film thickness of the photosensitive layer and the protective layer).
Is 20 μm or less, an electrophotographic photosensitive member for reversal development. 15. The electrophotographic photoreceptor for reversal development according to claim 1, wherein the charge generating substance contained in the charge generating layer is an azo pigment represented by the following formula (I). An electrophotographic photoreceptor for reversal development, which is characterized in that [Chemical 1] In the formula, Cp ₁ and Cp ₂ represent coupler residues. R ₂₀₁ ,
R ₂₀₂ represents a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group or a cyano group, and may be the same or different. Cp ₁ and Cp ₂ are as follows (II)
It is represented by a formula. [Chemical 2] In the formula, R ₂₀₃ represents a hydrogen atom, an alkyl group such as a methyl group or an ethyl group, or an aryl group such as a phenyl group. R
₂₀₄ , R ₂₀₅ , R ₂₀₆ , R ₂₀₇ and R ₂₀₈ are each a hydrogen atom, a nitro group, a cyano group, a halogen atom such as fluorine, chlorine, bromine or iodine, an alkyl such as a trifluoromethyl group, a methyl group or an ethyl group. Group, an alkoxy group such as a methoxy group and an ethoxy group, a dialkylamino group and a hydroxyl group, and Z is an atomic group necessary for constituting a substituted or unsubstituted aromatic carbocycle or a substituted or unsubstituted aromatic heterocycle. Represents 16. The electrophotographic photoreceptor for reversal development according to claim 15, wherein Cp ₁ and Cp ₂ of the azo pigments are different from each other. 17. The electrophotographic photosensitive member for reversal development according to claim 1, wherein the charge generating substance contained in the charge generating layer is a diffraction peak of a Bragg angle 2θ with respect to a characteristic X-ray of CuKα. An electrophotographic photoreceptor for reversal development, which comprises titanyl phthalocyanine having a maximum diffraction peak at least at 27.2 ° as (± 0.2 °). 18. An electrophotographic method comprising repeating at least charging, image exposure, reversal development and image transfer using the reversal development electrophotographic photosensitive member according to claim 1. Description: . 19. An electrophotographic apparatus comprising at least the electrophotographic photoconductor for reversal development according to claim 1, a charging unit, an image exposing unit, a reversal developing unit and a transfer unit. . 20. A process cartridge for an electrophotographic apparatus which carries out reversal development, comprising at least the electrophotographic photoconductor for reversal development according to any one of claims 1 to 17.