JP2003043718A - Electrophotographic photoreceptor, method for manufacturing electrophotographic photoreceptor, process cartridge and electrophotographic device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrophotographic photoreceptor excellent in both of potential characteristics and image characteristics which does not cause image defects such as thinning in an image or production of black spot defects or fog under the conditions of temperature and humidity in a wide range. SOLUTION: In the electrophotographic photoreceptor having an intermediate layer and a photosensitive layer in this order on a conductive supporting body, the intermediate layer contains crystalline particles expressed by composition formula (1): Al2 O3 -nH2 O (wherein n is >=0) and an aluminum salt compound of an organic acid. The method for manufacturing the electrophotographic photoreceptor, and the process cartridge and the electrophotographic device also have the above features.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an electrophotographic photoreceptor, and more particularly to an electrophotographic photoreceptor having an intermediate layer containing fine particles having a specific composition and an inorganic binder having a specific composition. The present invention also relates to a method for manufacturing the electrophotographic photosensitive member, a process cartridge, and an electrophotographic apparatus.

[0002]

2. Description of the Related Art An electrophotographic photosensitive member usually has a photosensitive layer on a conductive support, but the photosensitive layer is generally a very thin layer, and the photosensitive layer is damaged due to defects on the surface of the support such as scratches and deposits. There was a case where the film thickness of the film became uneven. This tendency is that the current mainstream photosensitive layer is 0.5 μm.
This is particularly remarkable in a so-called function-separated type photosensitive layer having a charge generation layer and a charge transport layer having extremely thin film thicknesses. When the film thickness of the photosensitive layer is not uniform, potential unevenness and sensitivity unevenness naturally occur, so it is necessary to form the photosensitive layer as uniformly as possible. If these potential unevenness and sensitivity unevenness occur, black spot defects (black spots) and fog occur in the image.

On the other hand, as a means for sharpening the potential distribution of the electrostatic latent image, a method of reducing the thickness of the electrophotographic photoconductor can be considered. For example, in the case of a laminated photoreceptor, the charges generated in the charge generation layer are injected into the charge transport layer and move to the surface along the electric field to neutralize the surface potential of the photoreceptor to form an electrostatic latent image. A sharp electrostatic latent image that is faithful to digital light such as laser light by suppressing the diffusion of charges in the direction perpendicular to the electric field by increasing the electric field strength and decreasing the diffusion distance by decreasing the thickness of the charge transport layer. Can be formed. Also, considering the photoconductor as a kind of dielectric, the capacitance of the photoconductor increases by decreasing the film thickness,
Therefore, the charge density on the surface of the photoconductor is increased to obtain a predetermined surface potential, and as a result, the developing electric field is increased, the potential of the electrostatic latent image becomes deeper in the potential direction, and high resolution is realized.

However, in conventional photoconductors, when the film becomes thin, the electric field strength increases, so that charge injection from the support side is promoted, and a phenomenon such as a decrease in charging ability and so-called fog in the reversal developing system appears. Therefore, if the film thickness of the photoconductor is reduced, dot reproducibility of digital light such as a laser is improved and the resolution is increased, but there is a problem in practical use because there is a problem due to charge injection.

Therefore, the function of covering defects on the surface of the support between the support and the photosensitive layer, improving the adhesiveness between the support and the photosensitive layer, and preventing carrier injection from the support to the photosensitive layer. It is proposed to provide an intermediate layer having

Conventionally, this intermediate layer is made of polyamide (JP-A-48-47344 and JP-A-52-25638), polyester (JP-A-52-20836 and JP-A-54-26738). ), Polyurethane (JP-A-53-89435 and JP-A-2-115858)
Gazette), quaternary ammonium salt-containing acrylic polymer
Means for forming with resin such as (JP-A-51-126149) and casein (JP-A-55-103556) are known. However, the electrophotographic photosensitive member using the above material as the intermediate layer, the electrical resistance of the intermediate layer is likely to change in response to changes in temperature and humidity, stable and excellent in all environments from low temperature low humidity to high temperature high humidity. It was difficult to prepare an electrophotographic photosensitive member having excellent potential characteristics and capable of forming an excellent image.

For example, when the photoconductor is used under low temperature and low humidity where the electric resistance of the intermediate layer is apt to increase, electric charges are likely to remain in the intermediate layer, and the bright portion potential and the residual potential increase. As a result, fog occurs in the copy image in regular development, and the image becomes lighter in reverse development.
There is a problem that images having a predetermined image quality cannot be continuously obtained. Further, under high temperature and high humidity where the electric resistance of the intermediate layer is likely to decrease, the barrier function of the intermediate layer decreases, carrier injection from the support easily increases, and the dark area potential decreases. As a result, the image may be thinned in the regular development, and black dot defects (black spots) and fog may be generated in the image in the reversal development.

Further, in JP-A-62-272277, there is used a means for forming an intermediate layer by coating a coating solution prepared by mixing an organic metal compound such as silane coupling or metal alkoxide in an organic solvent. ing. These intermediate layers form a coating film by using a solution of a relatively low molecular weight organometallic compound as a coating liquid, and hydrolyze each organometallic compound in the process of drying it to cause their polymerization to form a network structure. Hardening and film formation are carried out. However, in such a manufacturing method, there is a point that the film forming property thereof is insufficient such as cracking when the film thickness exceeds a certain level. When a crack is generated in the intermediate layer, the cracked portion may cause a thin image in the regular development, or may cause a black dot defect (black spot) and a fog in the image in the reversal development. Therefore, when forming a coating film by coating a coating liquid prepared by mixing an organic metal compound in an organic solvent, it is necessary to suppress the film thickness to a certain degree or less and to cure and form a relatively thin film. However, when it is used in such a film thickness, the performance of preventing carrier injection from the support to the photosensitive layer as an intermediate layer becomes insufficient, and the image is thinned in the regular development, and black dot defects (black spots) are observed in the image in the reversal development. It was very difficult to make the image characteristics and the potential characteristics compatible with each other. Also,
Alkoxides, acetylacetonates, and the like, which are organic metal compounds such as zirconium, titanium, and aluminum used in the coating solution for these intermediate layers are highly hydrolyzable, and the coating solution containing an organic solvent as a main component precipitates over time. There is also a problem in storage that a product is produced and the viscosity is increased due to gelation.

On the other hand, in order to improve the unevenness of the surface of the support and to improve the charging property, many proposals have been made to apply anodizing treatment to an aluminum support to provide an alumite coating. However, this method has a problem that it requires a special bath and technique for performing the anodizing process, and is time-consuming, labor-intensive and costly.

[0010]

SUMMARY OF THE INVENTION Therefore, the present invention is intended to solve the above-mentioned problems in the prior art. That is, an object of the present invention is to provide an intermediate layer which does not require a special technique, is inexpensive, can be formed without causing cracks, and has good storage stability of a coating solution. Even when the photoconductor film thickness is reduced by using a layer, in a wide range of temperature and humidity conditions, the image becomes thin, and image defects such as black spot defects (black spots) and fog do not occur, potential characteristics, image An object is to provide an electrophotographic photoreceptor having excellent characteristics.

[0011]

That is, the present invention provides an electrophotographic photoreceptor having an intermediate layer and a photosensitive layer on a conductive support in this order, wherein the intermediate layer has the following composition formula (1) Al ₂ O ₃ An electrophotographic photosensitive member comprising: crystalline particles represented by nH ₂ O (1) (n is 0 or more) and an aluminum salt compound of an organic acid.

The present invention also provides a process cartridge and an electrophotographic apparatus having the above electrophotographic photosensitive member.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION The above composition formula (1) is, for example,
Alumina, alumina hydrate (aluminum hydroxide), al
Minagel, Emery, Corundum, Sapphire, Dia
Spore, norstrandite, hydrazirite (gib
Site), vialite, boehmite, lucarox, etc.
Alumina has the composition formula Al
_TwoO_ThreeAnd α-alumina having a corundum structure
Γ-alumina and δ-alcohol also called transition alumina
Mina, θ-alumina, etc. are present. Also, alumina hydration
The composition (aluminum hydroxide) is the composition formula Al_TwoO_Three・ H_TwoO also
Or Al_TwoO_Three・ 3H _TwoO or Al_TwoO_Three・ 1 /
5H_TwoRepresented by O, gibbsite, vialite, north
Transit, boehmite, diaspore, todite
Exists.

Typical methods for synthesizing the component represented by the composition formula (1) include Bayer method, aluminum alum thermal decomposition method, organoaluminum compound hydrolysis method, aluminum underwater discharge method and the like. In the present invention,
When synthesizing the particles represented by the composition formula (1), it is preferable that impurities such as alkali metal, alkaline earth metal, and halide ion do not exist, and the synthesis method is a highly pure organoaluminum compound. Is preferably used as a raw material.

Examples of the organoaluminum compound used in this case include trimethylaluminum,
Alkyl aluminums such as triethyl aluminum,
Aluminum chelate compounds such as aluminum triethoxide, aluminum triisopropoxide, aluminum alkoxides such as aluminum trisec-butoxide, aluminum triacetylacetonate, β-diketonates such as aluminum tris (ethylacetoacetate), and the like. can give.

As the method for synthesizing the crystalline fine particles represented by the composition formula (1) used in the present invention from the organoaluminum compound, the organoaluminum compound is thermally decomposed under reduced pressure, and water is added to the organoaluminum compound. There are methods such as hydrolysis. When an aluminum compound is thermally decomposed under reduced pressure, δ-alumina similar to γ-alumina is produced at a relatively low temperature, and θ-alumina or α-alumina is produced at a high temperature of 1000 ° C. or higher. In addition, in the method of hydrolyzing an organoaluminum compound, at room temperature to 100 ° C. or lower, vialite or boehmite is generated depending on the pH of the hydrolyzed solution, and is transformed into alumina by heating. Hydrothermal synthesis is a method of synthesizing boehmite particles from an organoaluminum compound. Boehmite particles can be synthesized by hydrolyzing and grain-growing an organoaluminum compound in an autoclave or an airtight container as an alternative thereto at 100 ° C. or higher.

In the present invention, the crystalline fine particles are used as an inorganic binder of an aluminum salt compound of an organic acid and dispersed in the inorganic binder. The crystalline fine particles preferably have high reactivity with the binder component. Alumina particles having high reactivity on the particle surface or boehmite particles obtained by decomposing a hydrolyzable organic aluminum compound are preferable.

The average particle diameter of the primary particles of the crystalline fine particles represented by the composition formula (1) used in the present invention is from 1 nm to
It is preferably 10 μm. If it exceeds 10 μm, the dispersibility becomes poor and the stability of the coating liquid tends to be low, and
If the thickness is less than m, the coating film becomes thin and the performance of preventing carrier injection from the support to the photosensitive layer as an intermediate layer tends to be insufficient. The average particle diameter can be determined by observing the intermediate layer with a transmission electron microscope, measuring the major axis of arbitrary 100 particles, and averaging them.

On the other hand, an aluminum salt compound of an organic acid as an inorganic binder component is obtained by heating an aqueous dispersion sol obtained by reacting an organic aluminum compound or a hydrolyzate of an organic aluminum compound with an organic acid. .

As described above, when the hydrolyzable organoaluminum compound is hydrolyzed, at room temperature to 100 ° C. or less, vialite or boehmite is produced depending on the pH in the hydrolyzed solution, and is transformed into alumina by heating.
A so-called alumina sol or boehmite sol is synthesized by hydrolyzing an organoaluminum compound with a large amount of water or warm water, adding an acid thereto and heating and growing the particles to uniformly disperse the particles. The solid content in the sol obtained by this method is mainly crystalline boehmite particles,
As the acid, a strong acid such as hydrochloric acid or nitric acid is usually used, and the amount of the acid at this time is 0.05 to a molar ratio with respect to aluminum.
0.1 is considered suitable.

When the sol synthesized as described above is coated and heated to form a film, it is 300 to 50.
At heating temperatures up to about 0 ° C., a boehmite crystalline phase is formed, and at temperatures higher than that, various alumina crystalline phases are formed. This is clarified from the result of X-ray diffraction analysis, and in such a generally known sol, since the fine particles present in the liquid are boehmite crystals, A broad diffraction pattern that is indexed to the crystal phase of boehmite is observed even when dried at cryogenic temperatures. The diffraction pattern may be broader, but this is because the interplanar water intercalation of boehmite causes a larger interplanar spacing than that of normal boehmite, and such boehmite is pseudo-boehmite. Sometimes called.

The aluminum salt compound of an organic acid used as the inorganic binder component in the present invention is different from the above-mentioned so-called alumina sol or boehmite sol in that the organic acid is coordinated with aluminum to form a dispersion in a water-dispersed sol. Generation of boehmite crystal particles is suppressed, and the aluminum salt structure of organic acid is the main component. This is characterized in that the water-dispersed sol is dried at a low temperature to leave an organic component in the film after drying, and does not show a diffraction pattern of boehmite by a usual X-ray diffraction analysis means.

Further, the fact that the aluminum salt structure of an organic acid is formed is due to the ¹³ C-NMR of a carboxyl group (--COO--).
It can be seen from the fact that the spectrum signal is observed at a position different from that of the released carboxylic acid, and that the absorption of the carboxyl group in the Raman spectrum shifts compared to the released carboxylic acid. From these analyzes, there are a plurality of binding forms of aluminum and carboxylic acid, and these binding forms may include a structure in which a carboxyl group crosslinks aluminum, a bidentate coordination structure, and the like. The salt compound represents all of these structures in which aluminum and a carboxyl group are bonded.

Examples of preferable organic aluminum compounds used in synthesizing the aluminum salt compound of an organic acid in the present invention include, for example, alkylaluminums such as toluar aluminum and triethylaluminum, aluminum triethoxide, aluminum trioxide. Examples thereof include aluminum alkoxides such as isopropoxide and aluminum trisec-butoxide, and aluminum chelate compounds such as aluminum triacetylacetonate and β-diketonate such as aluminum tris (ethylacetoacetate). Among these, aluminum tri-sec-butoxide is particularly preferable from the viewpoint of easy synthesis of the water-dispersed sol.

In the present invention, the organoaluminum compound preferably does not contain impurities such as alkali metals, alkaline earth metals and halide ions.

The acid used when synthesizing the aluminum salt compound of an organic acid in the present invention is an organic acid in consideration of not corroding the support or other underlayer as a coating solution for the intermediate layer. . As the organic acid, acetic acid or formic acid is preferable. Usually, when an acid such as a carboxylic acid (RCOOH) that serves as a ligand having a strong binding force is added to an organoaluminum compound such as an alkoxide, the ligands are exchanged and an aluminum salt structure of an organic acid can be obtained.

In the present invention, the organic acid (RCOOH) and aluminum (Al) used to obtain the water-dispersed sol.
The molar ratio of RCOOH / Al is preferably 0.5 to 1.

In the present invention, the crystalline fine particles represented by the above compositional formula (1) are dispersed in the thus obtained water-dispersed sol, preferably 100 to 250 ° C., more preferably 120 to 160 ° C. It can be obtained by drying. If the drying temperature is less than 100 ° C, the strength of the intermediate layer tends to be weak, and if it exceeds 250 ° C, the sensitivity of the electrophotographic photosensitive member tends to be deteriorated. Further, in the present invention, by heating the water-dispersed sol to such a temperature, the aluminum salt compound of the organic acid in the water-dispersed sol is cured and sufficient film-forming property can be obtained.

In the present invention, the coating liquid used for the intermediate layer may contain a surfactant or the like for improving dispersion and film-forming property. The addition of the surfactant is effective when the coating solution has a low viscosity when forming a coating film on the support and the film forming property is low.

Further, in the present invention, it is preferable that the added surfactant or the like is thermally decomposed during heating or film formation and hardly remains in the film, and an organic binder resin component is added to form an intermediate layer. It is not preferable to form since the resin component is likely to remain in the film of the intermediate layer, and the electric resistance is likely to decrease under high temperature and high humidity. Therefore, in the present invention, the proportion of the organic compound contained in the intermediate layer is preferably 1% by mass or less based on the total weight of the intermediate layer in terms of mass ratio.

The thickness of the intermediate layer in the present invention is
It is preferably 0.1 to 5 μm, and particularly preferably 0.3 to 1
It is preferably μm. If the film thickness is less than 0.1 μm, it is difficult to obtain the effect of the present invention, and if it exceeds 5 μm, the bright portion potential and the residual potential are likely to increase.

The photosensitive layer of the present invention contains a charge generating substance and a charge transporting substance in the same layer, that is, a so-called single layer type, and a charge generating layer containing the charge generating substance and a charge transporting layer containing the charge transporting substance. It is roughly classified into a so-called laminated type. The laminated type is further classified into a type having a conductive support, a charge generation layer and a charge transport layer in this order and a type having a conductive support, a charge transport layer and a charge generation layer in this order. In the present invention, a laminated type, particularly a type in which a charge transport layer is laminated on a charge generation layer, is preferable.

The charge generation layer includes azo pigments such as monoazo, bisazo and trisazo; phthalocyanine pigments such as metal phthalocyanine and metal-free phthalocyanine; indigo pigments such as indigo and thioindigo; polycyclic quinone pigments such as anthanthrone and pyrenequinone. Perylene pigments such as perylene anhydride and perylene imide; squarylium pigments; pyrylium and thiapyrylium salts;
And a charge generating substance such as a triphenylmethane dye, using a suitable solvent, a binder resin (binder resin), for example, polyvinyl acetal, polystyrene, polyester, polyvinyl acetate, methacrylic resin, acrylic resin, polyvinylpyrrolidone and cellulose type. It can be formed by applying a solution dispersed in a resin such as a resin and drying. The thickness of the charge generation layer is usually preferably 5 μm or less, and particularly preferably 0.05 to 2 μm.

The charge transport layer is obtained by coating a solution of a film-forming resin with a charge transport material as described below,
It is formed by drying. Charge transport materials are roughly classified into electron transport materials and hole transport materials. Examples of electron transport materials include 2,4,7-trinitrofluorenone, 2,4,
Examples thereof include electron-accepting substances such as 5,7-tetranitrofluorenone, chloranil and tetracyanoquinodimethane, and polymers obtained by polymerizing these substances. Examples of the hole-transporting substance include polycyclic aromatic compounds such as pyrene and anthracene; heterocyclic compounds such as carbazole, indole, imidazole, oxazole, thiazole, oxadiazole, pyrazole, pyrazoline, thiadiazole and triazole; p-diethylaminobenzaldehyde- Hydrazone compounds such as N, N-diphenylhydrazone and N, N-diphenylhydrazino-3-methylidene-9-ethylcarbazole; α-phenyl-4′-N, N-diaminostilbene and 5- [4- (di -P-tolylamino) benzylidene] -5H-dibenzo [a, d] dicycloheptene and other styryl compounds; benzidine compounds; triarylamine compounds; triphenylamine or groups consisting of these compounds in the main chain or side chain Polymers that have Examples thereof include poly-N-vinylcarbazole and polyvinylanthracene). Examples of the film-forming resin include polyester, polycarbonate, polymethacrylic acid ester, polystyrene and the like.
The thickness of the charge transport layer is preferably 5 to 40 μm, and particularly preferably 10 to 30 μm. preferable. In particular, the present invention can obtain a higher-definition image, but can exert a remarkable effect even when the film thickness of the charge transport layer is 15 μm or less, where fog is very likely to occur.

In the case of a single layer type, it can be formed by applying a solution in which the above-mentioned charge generating substance and charge transporting substance are dispersed and dissolved in a binder resin, and drying. In the case of a single layer type, the thickness of the photosensitive layer is 5 to 40
The thickness is preferably μm, and particularly preferably 10 to 30 μm. preferable. For the same reason as that of the charge transport layer, the film thickness of the single-type photosensitive layer is also preferably 15 μm or less.

In the present invention, an organic photoconductive polymer layer such as polyvinylcarbazole or polyvinylanthracene, a vapor deposition layer of the above-mentioned charge generating substance, a selenium vapor deposition layer, a selenium-tellurium vapor deposition layer, an amorphous silicon layer and the like are also used as the photosensitive layer. be able to.

Examples of the conductive support used in the present invention include aluminum, aluminum alloys, copper, zinc, stainless steel, titanium, nickel, indium, gold and platinum. In addition, plastics (for example, polyethylene, polypropylene, polyvinyl chloride, polyethylene terephthalate, acrylic resin, etc.) formed by coating such metals or alloys by a vacuum vapor deposition method, or conductive particles together with a suitable binder resin, such plastics, metals Alternatively, a support coated on an alloy support, a support obtained by impregnating plastic or paper with conductive particles, or the like can be used. In particular, the conductive layer obtained by dispersing the conductive fine particles in a polymer binder and applying it is easy to form and is suitable for forming a uniform surface. The conductive fine particles used at this time have a primary particle diameter of 100 nm or less, and more preferably 50 nm or less. As the conductive fine particles, conductive zinc oxide, conductive titanium oxide, Al, Au, Cu, A
g, Co, Ni, Fe, carbon black, ITO, tin oxide, indium oxide, indium, etc. are used,
These may be used by coating the surface of the insulating fine particles. The content of the conductive fine particles is used so that the volume resistance is sufficiently low, preferably 1 × 10 ¹⁰ Ωc
It is added so that the resistance becomes m or less. It is more preferably used at 1 × 10 ⁸ Ωcm or less. Examples of the shape of the support include a drum shape, a sheet shape, and a belt shape, but it is preferable to make the shape most suitable for the electrophotographic photoreceptor to be applied.

When exposure is performed using a coherent light source such as a laser, unevenness can be formed on the surface of the conductive base material in order to prevent image deterioration due to interference. At this time, in order to prevent defects such as charge injection and uneven residual potential from occurring, unevenness of about 1 / 2λ of the wavelength used is dispersed at intervals of 10 μm or less by dispersing an insulator such as silica beads having a diameter of several μm or less. It can be formed and used. Further, as another method, it is possible to form the unevenness by roughening the surface by a method such as etching, blasting, cutting, or the like.

Further, in the present invention, a resin layer or a resin layer containing conductive particles may be laminated as a protective layer on the photosensitive layer.

Examples of the coating method of the various layers described above include a dip coating method, a spray coating method, a beam coating method, a spinner coating method, a roller coating method, a Mayer bar coating method and a blade coating method.

FIG. 1 shows a schematic structure of an electrophotographic apparatus using a process cartridge having the electrophotographic photosensitive member of the present invention.

In the figure, reference numeral 1 is a drum-shaped electrophotographic photosensitive member of the present invention, which is rotationally driven around a shaft 2 in a direction of an arrow at a predetermined peripheral speed. In the rotating process, the electrophotographic photosensitive member 1 is uniformly charged with a positive or negative predetermined potential on its peripheral surface by the primary charging unit 3, and then from an exposing unit (not shown) such as slit exposure or laser beam scanning exposure. The exposure light 4 which is emphasized and modulated corresponding to the time-series electric digital image signal of the target image information to be output is received. In this way, electrostatic latent images corresponding to target image information are sequentially formed on the peripheral surface of the electrophotographic photosensitive member 1.

The formed electrostatic latent image is then developed by the developing means 5.
Toner is developed by the electrophotographic photosensitive member 1 and is transferred between the electrophotographic photosensitive member 1 and the transfer unit 6 from a sheet feeding unit (not shown) in synchronization with the rotation of the electrophotographic photosensitive member 1. The toner images formed and carried on the surface of the photoconductor 1 are sequentially transferred by the transfer unit 6.

The transfer material 7 to which the toner image has been transferred is separated from the surface of the electrophotographic photosensitive member and introduced into the image fixing means 8 to undergo image fixing, thereby being printed outside the apparatus as an image formed product (print, copy). Will be out.

The surface of the electrophotographic photosensitive member 1 after the image transfer is cleaned by the cleaning means 9 to remove the residual toner after transfer, and is further neutralized by the pre-exposure light 10 from the pre-exposure means (not shown). After that, it is repeatedly used for image formation. If the primary charging means 3 is a contact charging means using a charging roller or the like, pre-exposure is not always necessary.

In the present invention, among the components such as the electrophotographic photoreceptor 1, the primary charging means 3, the developing means 5 and the cleaning means 9 described above, a plurality of components are housed in a container 11 and integrally combined as a process cartridge. The process cartridge may be detachably attached to the main body of the electrophotographic apparatus such as a copying machine or a laser beam printer. For example, at least one of the primary charging unit 3, the developing unit 5, and the cleaning unit 9 is attached to the electrophotographic photoreceptor 1.
In addition, the process cartridge can be integrally supported and formed into a cartridge, and the guide cartridge 12 such as a rail of the apparatus main body can be used to form a process cartridge that can be attached to and detached from the apparatus main body.

Further, when the electrophotographic apparatus is a copying machine or a printer, the exposure light 4 is reflected light or transmitted light from the original, or the original is read by a sensor, converted into a signal, and the laser is produced in accordance with this signal. Beam scanning, LED
The light is emitted by driving the array and driving the liquid crystal shutter array.

The electrophotographic photoconductor of the present invention can be applied to general electrophotographic apparatuses such as copying machines, laser printers, LED printers and liquid crystal shutter type printers.
It can be widely applied to devices such as plate making and facsimile.

[0049]

EXAMPLES The present invention will be described in more detail with reference to the following examples.

(Example 1) 20 g of aluminum trisec-butoxide was placed in a flask and heated with hot water 1
80 g and formic acid 0.2 g were added. After the addition, stirring was continued for 10 minutes to obtain a white water-solvent sol. The flask was heated in a 100 ° C. oil bath for 4 days with vigorous stirring.
After that, it is diluted with 200 g of ion-exchanged water to give an average particle size of 2
4.1 g of 0 nm boehmite particles (trade name: Dispal, manufactured by Vista Chemical Company) were added and stirred to prepare a coating liquid for the intermediate layer.

Next, the surface is cut (surface roughness (JIS
Ten-point average roughness Rz) defined by B 601 = 0.5μ
m) aluminum cylinder (outer diameter 30 mm x length 2
54 mm) by applying the coating solution for the intermediate layer by the dip coating method and drying at 160 ° C. for 2 hours,
An intermediate layer having a thickness of 0.7 μm was formed.

Next, 4 parts by weight of oxytitanium phthalocyanine pigment, polyvinyl butyral (trade name BX-1,
Sekisui Chemical Co., Ltd.) 2 parts by weight, cyclohexanone 34
After a mixed solution containing 1 part by weight was dispersed by a sand mill for 10 hours, 60 parts by weight of tetrahydrofuran was added to prepare a coating liquid for charge generation layer. This coating solution was applied onto the above intermediate layer by a dip coating method and dried by heating at 83 ° C. for 10 minutes to form a charge generation layer having a thickness of 0.2 μm. Next, 50 parts by weight of a triarylamine compound represented by the following structural formula,

[Outer 1]

Polycarbonate (Iupilon Z-20
A solution prepared by dissolving 50 parts by weight of Mitsubishi Gas Chemical Co., Ltd. in 400 parts by weight of chlorobenzene was applied on the charge generation layer by a dip coating method, and the solution was applied at 117 ° C. for 1 hour.
The film was heated and dried for an hour to form a charge transport layer having a film thickness of 15 μm to prepare an electrophotographic photoreceptor.

The prepared electrophotographic photosensitive member was mounted on an electrophotographic printer of reversal development, and was kept at normal temperature and humidity (25 ° C.).
/ 50% RH), low temperature low humidity (15 ° C / 15% RH) and high temperature high humidity (30 ° C / 80% RH) dark area potential
(Vd) and bright part potential (Vl) were measured and image evaluation was performed.
As a result, as shown in Table 1, this electrophotographic photosensitive member was able to obtain a large contrast between the dark portion potential (Vd) and the light portion potential (Vl) even at low temperature and low humidity and high temperature and high humidity. In addition, as shown in Table 2, unnecessary black dot defects (black dots)
A very excellent and high-quality image having no fogging and no toner scattering was obtained.

(Example 2) 20 g of aluminum trisec-butoxide was placed in a flask and heated with hot water 1
80 g and formic acid 0.2 g were added. After the addition, stirring was continued for 10 minutes to obtain a white water-solvent sol. This flask
Heated in a 100 ° C. oil bath for 4 days with vigorous stirring. Then, it is diluted with 200 g of ion-exchanged water so that the average particle size is 20 n.
m-Alumina particles (trade name: aluminum oxide C, manufactured by Nippon Aerosil Co., Ltd.) (3.5 g) were added and stirred to prepare a coating solution for the intermediate layer.

Next, an intermediate layer was formed in the same manner as in Example 1 except that the intermediate layer was formed using the above coating liquid. Next, a charge generation layer and a charge transport layer were formed in the same manner as in Example 1, an electrophotographic photosensitive member was produced, and evaluation was performed in the same manner as in Example 1. As a result, as shown in Table 1, the electrophotographic photoreceptor has a dark area potential even at low temperature and low humidity and high temperature and high humidity.
A large contrast could be obtained between (Vd) and the bright part potential (Vl). In addition, as shown in Table 2, there were obtained unnecessary black spot defects (black spots) and fog, and a very high-quality image having no toner scattering was obtained.

Example 3 20 g of aluminum trisec-butoxide was placed in a flask, and 240 g of ion-exchanged water and 3.6 g of acetic acid were added with stirring. After the addition, vigorous stirring was continued at room temperature for 7 days to obtain a transparent water-solvent sol.
Then, 4.1 g of boehmite particles having an average particle size of 20 nm (trade name: Dispal, manufactured by Vista Chemical Company)
Was added and stirred to prepare an intermediate layer coating liquid.

Next, an intermediate layer was formed in the same manner as in Example 1 except that the intermediate layer was formed using the above coating liquid. Next, a charge generation layer and a charge transport layer were formed in the same manner as in Example 1, an electrophotographic photosensitive member was produced, and evaluation was performed in the same manner as in Example 1. As a result, as shown in Table 1, the electrophotographic photoreceptor has a dark area potential even at low temperature and low humidity and high temperature and high humidity.
A large contrast could be obtained between (Vd) and the bright part potential (Vl). In addition, as shown in Table 2, there were obtained unnecessary black spot defects (black spots) and fog, and a very high-quality image having no toner scattering was obtained.

Example 4 20 g of aluminum trisec-butoxide was placed in a flask, and 240 g of ion-exchanged water and 3.6 g of acetic acid were added with stirring. After the addition, vigorous stirring was continued at room temperature for 7 days to obtain a transparent water-solvent sol.
Thereafter, 3.5 g of alumina particles (trade name: AKP-30, manufactured by Sumitomo Chemical Co., Ltd.) was added and stirred to prepare a coating liquid for the intermediate layer.

Next, an intermediate layer was formed in the same manner as in Example 1, except that the above coating liquid was used to form the intermediate layer. Next, a charge generation layer and a charge transport layer were formed in the same manner as in Example 1, an electrophotographic photosensitive member was produced, and evaluation was performed in the same manner as in Example 1. As a result, as shown in Table 1, the electrophotographic photoreceptor has a dark area potential even at low temperature and low humidity and high temperature and high humidity.
A large contrast could be obtained between (Vd) and the bright part potential (Vl). Further, as shown in Table 2, there were few unnecessary black dot defects (black spots) and fog, and a very excellent high-quality image without toner scattering was obtained.

Comparative Example 1 As a coating liquid for the intermediate layer, alcohol-soluble copolymer nylon (Amilan CM-800) was used.
0, manufactured by Toray Industries, Inc.) 10 parts by weight with 60 parts by weight of methanol and n
Example 1 except that a solution prepared by dissolving 40 parts by weight of butanol was used as a coating solution for the intermediate layer and dried by heating at 90 ° C. for 10 minutes to form an intermediate layer having a film thickness of 1 μm.
An electrophotographic photosensitive member was produced in the same manner as.

The evaluation of electrophotographic characteristics was carried out in the same manner as in Example 1. As a result, as shown in Table 1, the electrophotographic photoreceptor has a dark area potential even at low temperature and low humidity and high temperature and high humidity.
Although a contrast could be obtained between (Vd) and the bright part potential (Vl), as shown in Table 2, at high temperature and high humidity, the local charge from the support, which was not reflected in the above potential measurement, was detected. Fog, which appears to be due to the injection, occurred and an extremely poor quality image was obtained.

(Comparative Example 2) An electrophotographic photosensitive member was produced in the same manner as in Example 1 except that the intermediate layer was not formed.

Evaluation of electrophotographic characteristics was carried out by the same method as in Example 1. As a result, as shown in Table 1, the electrophotographic photoreceptor has a dark area potential even at low temperature and low humidity and high temperature and high humidity.
Although a contrast could be obtained between (Vd) and the bright part potential (Vl), the chargeability was not so good at room temperature and normal humidity and high temperature and high humidity, and as shown in Table 2, charge injection from the support was performed. The image was not good due to black spot defects.

[0065]

[Table 1]

[0066]

[Table 2]

[0067]

As described above, according to the present invention, an electrophotographic photoreceptor having excellent potential characteristics and an excellent image in all environments from low temperature and low humidity to high temperature and high humidity, and the electrophotographic photoreceptor. The manufacturing method, the process cartridge, and the electrophotographic apparatus can be provided.

[Brief description of drawings]

FIG. 1 is a diagram showing an example of a schematic configuration of an electrophotographic apparatus including a process cartridge having an electrophotographic photosensitive member of the present invention.

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Claims (17)

[Claims] 1. An electrophotographic photoreceptor having an intermediate layer and a photosensitive layer in this order on a conductive support, wherein the intermediate layer has the following composition formula (1) Al ₂ O ₃ .nH ₂ O (1) (n is 0 or more.) An electrophotographic photoreceptor containing crystalline particles represented by the formula (1) and an aluminum salt compound of an organic acid. 2. The crystalline particles are boehmite.
The electrophotographic photosensitive member described. 3. The electrophotographic photosensitive member according to claim 1, wherein the crystalline particles have an average particle size of 10 to 100 nm. 4. The aluminum salt compound of an organic acid is obtained by heating an aqueous dispersion sol obtained by reacting an organic aluminum compound or a hydrolyzate of an organic aluminum compound with an organic acid.
The electrophotographic photosensitive member according to any one of 1. 5. The electrophotographic photosensitive member according to claim 4, wherein the heating temperature is 100 to 250 ° C. 6. The organic acid is acetic acid or formic acid.
Alternatively, the electrophotographic photosensitive member according to item 5. 7. The electrophotographic photosensitive member according to claim 4, wherein the molar ratio of organic acid to aluminum (organic acid / aluminum) is 0.5 to 1. 8. The ratio of the organic compound contained in the intermediate layer is 1% by mass or less based on the total mass of the intermediate layer.
The electrophotographic photosensitive member according to any one of 1. 9. A method for producing an electrophotographic photoreceptor having an intermediate layer and a photosensitive layer on a conductive support in this order, wherein the intermediate layer has the following composition formula (1) Al ₂ O ₃ .nH ₂ O (1). (N is 0 or more.) Aqueous dispersion sol containing crystalline particles represented by: and an aluminum salt compound of an organic acid obtained by reacting an organic aluminum compound or a hydrolyzate of an organic aluminum compound with an organic acid. A method for manufacturing an electrophotographic photosensitive member, which is formed by heating the electrophotographic photosensitive member. 10. The method for producing an electrophotographic photosensitive member according to claim 9, wherein the crystalline particles are boehmite. 11. The method for producing an electrophotographic photosensitive member according to claim 9, wherein the crystalline particles have an average particle size of 10 to 100 nm. 12. The method for producing an electrophotographic photosensitive member according to claim 9, wherein the heating temperature is 100 to 250 ° C. 13. The method for producing an electrophotographic photosensitive member according to claim 9, wherein the organic acid is acetic acid or formic acid. 14. The molar ratio of organic acid to aluminum (organic acid / aluminum) is 0.5 to 1.
4. The method for producing an electrophotographic photosensitive member according to any one of 3 above. 15. The method for producing an electrophotographic photosensitive member according to claim 9, wherein the proportion of the organic compound contained in the intermediate layer is 1% by mass or less based on the total mass of the intermediate layer. 16. The electrophotographic photosensitive member according to claim 1, and a charging unit, a developing unit, and a cleaning unit that are integrally supported, and are removable from the main body of the electrophotographic apparatus. Process cartridge. 17. An electrophotographic apparatus comprising the electrophotographic photosensitive member according to claim 1, a charging unit, a developing unit and a transfer unit.