JP3287384B2 - Electrophotographic photoreceptor, process cartridge having the electrophotographic photoreceptor, and electrophotographic apparatus - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an electrophotographic photosensitive member, and more particularly, to an electrophotographic photosensitive member having an intermediate layer containing a resin having a specific structure. Further, the present invention relates to a process cartridge and an electrophotographic apparatus having the above-described electrophotographic photosensitive member.

[0002]

2. Description of the Related Art An electrophotographic photoreceptor usually has a photosensitive layer on a conductive support, but the photosensitive layer is generally an extremely thin layer. In some cases, the film thickness became non-uniform. The 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 small thicknesses. If the film thickness of the photosensitive layer is non-uniform, potential unevenness and sensitivity unevenness naturally occur, so that the photosensitive layer must be formed as uniformly as possible.

An important characteristic required for an electrophotographic photoreceptor is stability of a light portion potential and a dark portion potential during repeated use. If these potentials are not stable, the image density will not be stable or the image will fog.

Therefore, a function of covering a defect on the surface of the support between the support and the photosensitive layer, improving the adhesion between the support and the photosensitive layer, and preventing injection of carriers from the support into the photosensitive layer. It has been proposed to provide an intermediate layer having

Conventionally, as a resin used for the intermediate layer,
Polyamides (JP-A-48-47344 and JP-A-52-25638) and polyesters (JP-A-52-25638)
JP-A-2020836 and JP-A-54-26738), polyurethane (JP-A-53-89435 and JP-A-2-115858), and a quaternary ammonium salt-containing acrylic polymer (JP-A-51-1984). -126149
And casein (Japanese Patent Laid-Open No. 55-103556) are known.

However, in an electrophotographic photoreceptor using the above-mentioned material as an intermediate layer, the electric resistance of the intermediate layer easily changes in accordance with changes in temperature and humidity, and is stable in all environments from low temperature and low humidity to high temperature and high humidity. It has been difficult to produce an electrophotographic photosensitive member having excellent potential characteristics and capable of forming an excellent image.

For example, when the photoconductor is repeatedly used under low temperature and low humidity where the electric resistance of the intermediate layer tends 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, in the normal development, fogging may occur in the copy image, and in the reversal development, the image may become thin, and an image having a predetermined image quality may not be continuously obtained.

On the other hand, under high temperature and high humidity where the electric resistance of the intermediate layer tends to decrease, the barrier function of the intermediate layer decreases, carrier injection from the support increases, and the dark area potential decreases. As a result, the image may become thinner in the normal development, and black spot-like defects (black spots) or fog may occur in the image in the reverse development.

In addition, the provision of the intermediate layer often lowers the sensitivity of the photoreceptor itself even if the potential stability under low temperature and low humidity and the black spot defect on the image under high temperature and high humidity are improved. Was.

[0010]

SUMMARY OF THE INVENTION It is an object of the present invention to stably exhibit excellent potential characteristics in all environments from low temperature and low humidity to high temperature and high humidity, and to maintain excellent initial images. An object of the present invention is to provide an electrophotographic photosensitive member that can be formed.

[0011] Another object of the present invention is to provide a good image free from defects by interposing an intermediate layer having excellent film-forming properties between a support and a photosensitive layer containing a resin having excellent solubility. An object of the present invention is to provide an electrophotographic photoreceptor capable of forming an image.

It is another object of the present invention to provide a process cartridge and an electrophotographic apparatus having the above-described electrophotographic photosensitive member.

[0013]

That is, the present invention relates to an electrophotographic photosensitive member having a conductive support, an intermediate layer on the conductive support, and a photosensitive layer on the intermediate layer, wherein the intermediate layer is a repeating unit. The following equation (1)

[0014]

[Outside 10] (In the formula, A represents a tetravalent organic group, B represents a divalent organic group, R represents a hydrogen atom or an alkyl group.) Represented by
The amide acid structure or an amide acid ester structure are two or more kinds
An electrophotographic photoreceptor characterized by containing the above -mentioned copolymer (provided that the repeating unit of the copolymer has the following formula:
Combinations of the repeating units shown in (A) and (B)
) .

[0015]

[Outside 11] (In the formula, A ₁ represents a divalent organic group, and R ₁ and R ₂ are the same.
One or different hydrogen atoms, substituted or unsubstituted al
A kill group, a substituted or unsubstituted alkoxyalkyl group and
Shows the micro substituted or unsubstituted aralkyl group, or R ₃
R ₇ is a hydrogen atom, a halogen atom, a substituted or unsubstituted
Alkyl group, substituted or unsubstituted alkoxy group, substituted
Or an unsubstituted aryl, nitro or cyano group
Show. )

[0016]

[Outside 12] (In the formula, A ₂ represents a divalent organic group, and R ₈ and R ₉ are the same.
One or different hydrogen atoms, substituted or unsubstituted al
A kill group, a substituted or unsubstituted alkoxyalkyl group and
And a substituted or unsubstituted aralkyl group, and R ₁₀ is water
Elemental atom, halogen atom, substituted or unsubstituted alkyl
Group, substituted or unsubstituted alkoxy group, substituted or
Represents an unsubstituted aryl group, a nitro group and a cyano group;
₁₁ and R ₁₂ represent an alkyl group. Further , the present invention is a process cartridge and an electrophotographic apparatus having the electrophotographic photosensitive member.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION The copolymer used in the present invention is:
It may have only a plurality of types of amide acid structures, may have only a plurality of types of amide acid structures, or may have a total of two or more amide acid structures and amide acid structures.

According to this configuration, the solubility of the copolymer can be improved, and as a result, the film formability can be improved, and a good image without defects can be stably obtained. is there. In addition, since the solubility is improved, a low-boiling solvent such as an alcohol-based solvent or an ether-based solvent can be used, so that deterioration of electrophotographic properties due to the solvent remaining in the layer hardly occurs, and the resin-containing solvent is contained. Even if the intermediate layer of the present invention is formed on the layer to be formed, a smooth layer can be obtained without adversely affecting the lower layer.

The copolymer having an amide acid structure and an amide acid ester structure in the present invention can be synthesized using a diamine and a carboxylic acid or a carboxylic acid derivative. Such carboxylic acid derivatives include carboxylic esters and carboxylic anhydrides. The amide acid structure and the amide ester structure are represented by the following formula (1)

[0020]

[Outside 13] (In the formula, A represents a tetravalent organic group, B represents a divalent organic group, and R represents a hydrogen atom or an alkyl group.)

In the above formula (1), the tetravalent organic group of A has at least one cyclic group, and preferable examples include the following, but are not limited thereto.

[0022]

[Outside 14] In the above formula (1), the divalent organic group of B has at least a saturated hydrocarbon group, an aromatic hydrocarbon ring group or an aromatic heterocyclic group, and may have at least one cyclic group. preferable. For example, the following may be mentioned, but not limited to them.

[0023]

[Outside 15]

[0024]

[Outside 16] In the above formula (1), R includes a hydrogen atom and an alkyl group such as methyl, ethyl, n-propyl, iso-propyl, n-butyl, iso-butyl and tert-butyl.

The number average molecular weight of the copolymer used in the present invention is preferably from 500 to 100,000, and particularly preferably from 10,000 to 50,000.

In the present invention, the amide portion of the amide acid and the amic acid ester Tsubaki and the acid or acid ester portion may be dehydrated or dehydrated depending on the drying conditions in the drying step usually performed in the production of an electrophotographic photoreceptor. An imide structure may be formed by an alcohol reaction.

In the present invention, the number of the acid structure and the acid ester structure is preferably 20 to 80 mol%, more preferably 40 to 60 mol%, of the number of the acid structure, ester structure and imide structure of the whole copolymer. Preferably it is present. Although the reason is not clear, the acid or acid ester structure prevents the injection of holes from the conductive support, and facilitates the dissociation of carriers generated by the action of the charge generating substance and the injection of electrons into the intermediate layer. In addition, it is considered that the dissociation of the carrier, the injection and the movement of the electrons are made smoother, and the imide structure is made tightly packed, and the imide structure is less affected by moisture.

In the present invention, the ratio of the imide structure to the total number of the amide structure, amide structure and imide structure in the copolymer (imidation ratio, mol%) is as follows:
The infrared absorption spectrum of the sample is measured, and the infrared absorption spectrum can be determined from the absorbance at 1740 to 1780 cm ^-1 which is specific to the imide group. In addition, the sample H ¹
-It can also be obtained by measuring an NMR spectrum and determining the amount of protons of a carboxylic acid group and a carboxylic acid ester group.

Preferred examples of the repeating unit of the copolymer used in the present invention are shown below, but the invention is not limited thereto. The repeating unit is represented by the formula (1)
Is the basic type, and A, B, and R, which are the changing parts in the basic type, are represented. The numbers shown in parentheses are the molar ratios of the respective raw materials used in synthesizing the exemplified compounds.

[0030]

[Outside 17]

[0031]

[Outside 18]

[0032]

[Outside 19]

[0033]

[Outside 20]

[0034]

[Outside 21]

[0035]

[Outside 22]

[0036]

[Outside 23]

[0037]

[Outside 24]

[0038]

[Outside 25]

[0039]

[Outside 26] The copolymer used in the present invention is synthesized, for example, by a ring-opening polyaddition reaction of tetracarboxylic dianhydride or a dicarboxylic acid derivative obtained by half-esterifying the anhydride with a diamine in an organic polar solvent. Examples of such organic polar solvents include amide solvents such as N, N-dimethylacetamide, N, N-dimethylformamide and N-methylpyrrolidone; phenol solvents such as cresol and chlorophenol; ether solvents such as diethylene glycol dimethyl ether; These mixtures and the like can be mentioned. Further, in order to control the molecular weight of the resin, the reaction can be carried out by adding 5% by weight or less of water to the organic polar solvent. The reaction temperature is preferably from 20 to 120 ° C, particularly preferably from 20 to 40 ° C.

The above-mentioned polyimide can be synthesized by heat-treating the above polyamic acid or polyamic acid ester. The processing temperature is preferably from 50 to 400 ° C., and the processing time is preferably from 5 minutes to 4 hours.

The molar ratio of the starting material diamine to the carboxylic acid or carboxylic acid derivative is preferably 1: 1. In the present invention, three or more types of raw materials are used, and the molar ratio of all diamines to all carboxylic acids or carboxylic acid derivatives is preferably 1: 1. Diamine,
Alternatively, the ratio in the carboxylic acid or carboxylic acid derivative can be arbitrarily determined, but the largest component is 80%.
It is preferably at most mol%.

Hereinafter, examples of the synthesis of the copolymer used in the present invention will be described. (Synthesis Example) 6.66 g (0.015 mol) of 4,4 ′-(hexafluoroisopropylidene) diphthalic anhydride and 4,4 ′ while sending dry nitrogen gas to a 500 ml four-necked flask
-4.41 g (0.015 mol) of biphthalic anhydride and 150 g of N, N-dimethylacetamide were added. The solution is stirred vigorously at 25 ° C., and the
6.01 g of diaminodiphenyl ether (0.030 g)
mol) was added. When the mixture was stirred for 3 hours while continuously supplying nitrogen, the reaction liquid became a viscous pale yellow liquid. The reaction solution was dropped into a 1.51 / 1.51 water / methanol solution with vigorous stirring, and the precipitated polyamic acid was collected by filtration. The product is dried to give Exemplified Compound No. 9.80 g of a polyamic acid having 3 repeating units was obtained.

Other copolymers used in the present invention can be synthesized in the same manner as described above.

The intermediate layer in the present invention may be composed of only one layer, or may be composed of a plurality of layers, at least one of which contains the resin of the present invention. When the intermediate layer is composed of a plurality of layers, examples of the resin other than the resin of the present invention include polyamide, polyester, and phenol resin.

Further, the intermediate layer of the present invention may contain other resins, additives, conductive substances, and the like, if necessary, in an amount within a range where the effects of the present invention can be obtained. Other resins include polyamides, polyesters and phenolic resins, and additives include acceptor compounds such as 2,5,7-trinitrofluorenone and benzoquinone. Powders (eg, aluminum, copper, nickel, silver, etc.), short metal fibers, carbon fibers, conductive powders (eg, carbon black, titanium black, graphite, metal oxides and metal sulfides (eg, antimony oxide, indium oxide, Tin oxide, titanium oxide, zinc oxide, potassium titanate, barium titanate, magnesium titanate,
Zinc sulfide, copper sulfide, magnesium oxide, aluminum oxide, etc.), and those metal oxides and metal sulfides that have been surface-treated with a conductive substance, those that have been surface-treated with a silane coupling agent or titanium coupling agent, and Which has been subjected to reduction treatment].

In any case, the content of the copolymer of the present invention in the intermediate layer of the present invention is preferably from 10 to 90% by weight, particularly preferably 3 to 90% by weight, based on the total weight of the contained intermediate layer.
It is preferably from 0 to 70% by weight.

The thickness of the intermediate layer of the present invention can be appropriately set in consideration of electrophotographic characteristics, defects on the support, etc., and is preferably 0.1 to 50 μm, and particularly preferably 0 to 50 μm. It is preferably from 0.5 to 30 μm.

The photosensitive layer of the electrophotographic photoreceptor of the present invention contains a single layer containing a charge generating substance and a charge transporting substance in the same layer, and contains a charge generating layer containing a charge generating substance and a charge transporting substance. It is roughly classified into a laminate type having a charge transport layer. 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, it is preferable to use a laminate type, particularly a type in which a charge transport layer is laminated on a charge generation layer.

The charge generation layer is made of an azo pigment such as monoazo, bisazo and trisazo; a phthalocyanine pigment such as metal phthalocyanine and metal-free phthalocyanine; an indigo pigment such as indigo and thioindigo; Pigments; perylene pigments such as perylene anhydride and perylene imide; squarylium dyes; pyrylium and thiapyrylium salts; It can be formed by applying and drying a solution dispersed in a resin such as acetal, polystyrene, polyester, polyvinyl acetate, methacrylic resin, acrylic resin, polyvinylpyrrolidone, and cellulosic resin. The thickness of the charge generation layer is usually preferably 5 μm or less, particularly preferably 0.05 to 2 μm.

The charge transporting layer is formed by applying a solution in which the following charge transporting substance is dissolved in a binder resin solution and drying the solution. Charge transport materials are broadly classified into electron transport materials and hole transport materials. As electron transport materials,
2,4,7-trinitrofluorenone, 2,4,5,7
-Electron-accepting substances such as tetranitrofluorenone, chloranil, and tetracyanoquinodimethane, and polymerized substances thereof. Examples of the hole transport 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-funinyl-4′-N, N-diaminostilbene and 5- [4- (di -P-tolylamino)
Styryl compounds such as benzylidene] -5H-dibenzo [a, d] dicycloheptene; benzidine compounds;
Triarylamine-based compounds; triphenylamine or polymers having a group consisting of these compounds in the main chain or side chain (for example, poly-N-vinylcarbazole and polyvinylanthracene).

Examples of the binder resin include polyester, polycarbonate, polymethacrylate and polystyrene.

The thickness of the charge transport layer is preferably from 5 to 40 μm, and particularly preferably from 10 to 30 μm.

In the case of a single layer type, it can be formed by applying and drying a solution in which the above-described charge generating substance and charge transporting substance are dispersed and dissolved in a binder resin. At this time, the film thickness is preferably from 5 to 40 μm, particularly preferably from 10 to 30 μm.

Further, in the present invention, an organic photoconductive polymer layer such as polyvinyl carbazole and polyvinyl anthracene, a vapor deposition layer of the above-described charge generating substance, a selenium vapor deposition layer,
A selenium-tellurium vapor-deposited layer, an amorphous silicon layer and the like can also be used as the photosensitive layer.

Examples of the conductive support used in the present invention include aluminum, aluminum alloy, copper, zinc, stainless steel, titanium, nickel, indium, gold, and platinum. In addition, such metals and alloys,
A plastic (eg, polyethylene, polypropylene, polyvinyl chloride, polyethylene terephthalate, acrylic resin, etc.) coated with a vacuum coating method, or conductive particles (eg, carbon black and silver particles) together with a suitable binder resin as described above. A support coated on a plastic, metal or alloy support, a support in which conductive particles are impregnated in plastic or paper, or the like can be used. Examples of the shape of the support include a drum shape, a sheet shape, and a belt shape, and it is preferable that the shape is most suitable for the applied electrophotographic photosensitive member.

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

Examples of the method of applying 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 wire bar coating method and a blade coating method.

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

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

In FIG. 1, reference numeral 1 denotes a drum-shaped electrophotographic photosensitive member of the present invention, which is driven to rotate around a shaft 2 at a predetermined peripheral speed in a direction indicated by an arrow. The photoreceptor 1 rotates during the rotation process.
The peripheral surface thereof is uniformly charged with a predetermined positive or negative potential by the primary charging unit 3 and then receives image exposure light 4 from an image exposure unit (not shown) such as slit exposure or laser beam scanning exposure. Thus, an electrostatic latent image is sequentially formed on the peripheral surface of the photoconductor 1.

The formed electrostatic latent image is then transferred to developing means 5
The toner-developed image developed by the toner image is transferred from a paper supply unit (not shown) between the photoconductor 1 and the transfer unit 6 in synchronization with the rotation of the photoconductor 1 and fed to a transfer material 7 fed therefrom. The image is sequentially transferred by the transfer unit 6.

The transfer material 7 which has undergone the image transfer is separated from the photoreceptor surface, introduced into the image fixing means 8 and subjected to image formation to be printed out outside the apparatus as a copy.

After the transfer of the image, the surface of the photoreceptor 1 is cleaned by removing the untransferred toner by the cleaning means 9, and is further cleaned by a pre-exposure light 10 from a pre-exposure means (not shown).
Is used for image formation repeatedly after the charge removal processing. When the primary charging unit 3 is a contact charging unit using a charging roller or the like, the pre-exposure is not necessarily required.

In the present invention, a plurality of components such as the above-described electrophotographic photosensitive member 1, primary charging means 3, developing means 5, and cleaning means 9 are integrally connected as a process cartridge. The process cartridge may be configured to be detachable from a main body of an 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 integrally supported together with the photoreceptor 1 to form a cartridge, and is detachably attached to the apparatus main body by using a guide unit such as the rail 12 of the apparatus main body. The process cartridge 11 can be used.

When the electrophotographic apparatus is a copying machine or a printer, the image exposure light 4 is reflected or transmitted from the original, or the original is read by a sensor and converted into a signal. The light is irradiated by scanning a laser beam, driving an LED array, driving a liquid crystal shutter array, and the like.

On the other hand, when used as a facsimile printer, the image exposure light 4 becomes exposure light for printing received data. FIG. 2 is a block diagram showing an example of this case.

The controller 14 controls the image reading unit 13 and the printer 22. The entire controller 14 is controlled by the CPU 20. The read data from the image reading unit 13 is transmitted to the partner station through the transmission circuit 16. Data received from the partner station is sent to the printer 22 through the receiving circuit 15. Predetermined image data is stored in the image memory. Printer Controller 21 controls the printer 22. 17 is a telephone.

The image received from the line 18 (image information from a remote terminal connected via the line) is demodulated by the receiving circuit 15 and then decoded by the CPU 20 to be sequentially stored in the image memory 19. Is done. When the image of at least one page is stored in the memory 19, the image of the page is recorded.
The image information of one page is read from the image memory 19 and the decoded image information of one page is sent to the printer controller 21. Printer controller 21
Receives the image information of one page from the CPU 20, and controls the printer 22 to record the image information of the page. The CPU 20 is receiving the next page during recording by the printer 22.

Thus, the reception and recording of the image are performed.

[0070]

The present invention will be described in more detail with reference to the following examples. (Example 1) As a repeating unit, Compound No. 1 was used. A solution obtained by dissolving 5 parts (parts by weight, the same applies hereinafter) of a copolymer having an amide acid structure of 3 (number average molecular weight 10,000) in 95 parts of tetrahydrofuran is poured into an aluminum cylinder (outer diameter 3).
0 mm x 254 mm length) by dip coating, left at room temperature for 10 minutes,
By heating for 1 minute, an intermediate layer having a thickness of 1 μm was formed.

The imidation ratio of the copolymer was 42 mol% based on the result of measurement of the infrared absorption spectrum of the copolymer obtained by drying the same solution under the same conditions.

Next, the following equation

[0073]

[Outside 27] Was added to a solution of 2 parts of polyvinyl butyral (BX-1, manufactured by Sekisui Chemical Co., Ltd.) in 34 parts of cyclohexanone, and dispersed by a sand mill for 8 hours, and then 60 parts of tetrahydrofuran Was further added and diluted to obtain a solution for a charge generation layer. This solution is applied on the intermediate layer by dip coating, and dried to obtain a film thickness of 0.1.
A 2 μm charge generation layer was formed.

Then, the following formula

[0075]

[Outside 28] 5 parts of a triarylamine and a polycarbonate resin (Iupilon Z-200, Mitsubishi Gas Chemical Co., Ltd.)
5 parts of a solution prepared by dissolving 5 parts of monochlorobenzene in a dip coating method on the charge generating layer.
By drying for 0 minutes, an oven transport layer having a thickness of 15 μm was formed.

The obtained electrophotographic photosensitive member was charged, exposed, and exposed.
Attached to a reversal development type laser beam printer that performs the development-transfer-cleaning process in a cycle of 1.5 seconds, and endurance of 5,000 images continuously under high temperature and high humidity environment (30 ° C., 85% RH) The test was performed. The evaluation was performed by measuring the dark potential (V _D ) at the initial stage, measuring the bright potential (V _L ) at the initial stage and after the durability test, and visually evaluating the obtained image. Table 1 shows the results. (Examples 2 to 10) 3
In place of the copolymer having the amide acid structure of Example Compound 4, 8, 12, 15, 20, 21, 2,
An electrophotographic photoreceptor was prepared and evaluated in the same manner as in Example 1 except that copolymers having an amide acid or amide ester structure of 5, 30, and 32 were used. Table 1 shows the results. (Comparative Example 1) For the intermediate layer, 5 parts of alcohol-soluble copolymerized nylon (Amilan CM-8000, manufactured by Toray Industries, Inc.) was used as methanol 95.
An electrophotographic photoreceptor was prepared and evaluated in the same manner as in Example 1, except that the electrophotographic photoreceptor was formed using a solution dissolved in a part. Table 1 shows the results. Comparative Example 2 Zirconium tetraacetylacetonate (Z
10 parts of C150, manufactured by Matsumoto Kosho Co., Ltd.) and 20 parts of γ-methacryloxypropyltrimethoxysilane (KBM503, manufactured by Shin-Etsu Chemical Co., Ltd.), 400 parts of methanol, n-
A solution dissolved in a mixed solvent of 100 parts of butanol and 200 parts of n-amyl alcohol was used.
An electrophotographic photosensitive member was prepared and evaluated in the same manner as in Example 1, except that the photosensitive member was dried at 120 ° C. for 120 minutes. Table 1 shows the results. (Comparative Example 3) The copolymer having an amide acid structure of Formula 3 is represented by the following formula:

[0077]

[Outside 29] An electrophotographic photoreceptor was prepared and evaluated in the same manner as in Example 1 except that a copolymer having an amide acid structure represented by was used and dimethylformamide was used instead of tetrahydrofuran.
Table 1 shows the results. (Comparative Example 4) The intermediate layer was dried at 100 ° C for 60 minutes, and further dried for 250 minutes.
An electrophotographic photoreceptor was prepared and evaluated in the same manner as in Example 1, except that the intermediate layer was formed by heat treatment at 3 ° C. for 3 hours. In addition, as a result of analysis by an infrared absorption spectrum, the amide acid structure in the resin used for the intermediate layer was all imidized. Table 1 shows the results.

[0078]

[Table 1] Example 11 The aluminum cylinder used in Example 1 was coated with 25 parts of a resol-type phenol resin (Plyofen J-325, manufactured by Dainippon Ink Co., Ltd.) and tin oxide containing 10% antimony oxide. Conductive titanium oxide powder 50
, A mixture of 25 parts of methyl cellosolve and 5 parts of methanol was dispersed in a sand mill for 20 hours, and dried to form a first intermediate layer having a thickness of 10 µm. Next, a second intermediate layer was provided on the first intermediate layer in the same manner as in Example 2. However, the thickness of the second intermediate layer was 0.5 μm. Observation of the prepared sample with an optical microscope revealed that the sample had a smooth coated surface without cracks. (Comparative Examples 5 and 6) An electrophotographic photoreceptor was prepared in the same manner as in Example 11, except that the second intermediate layer was formed in the same manner as in Comparative Examples 2 and 3.
evaluated.

After the application of the second intermediate layer, cracks were observed in the first intermediate layer, which were visually observed.
(Example 12) Using an aluminum cylinder having an outer diameter of 30 mm and a length of 360 mm, the intermediate layer was dried at 170 ° C for 10 minutes.
An electrophotographic photosensitive member was prepared in the same manner as in Example 1, except that the thickness of the intermediate layer was 1.2 μm and the charge generation layer was formed as described below. (Formation method of charge generation layer)

[0080]

[Outside 30] Is added to 5 parts of a bisazo pigment represented by
And dispersed with a sand mill for 20 hours. Butyral resin (BLS, manufactured by Sekisui Chemical Co., Ltd.) 2.5
A liquid in which 20 parts of tetrahydrofuran was dissolved was added, and the mixture was further dispersed for 2 hours. Cyclohexanone 10
A solution diluted by adding 0 parts and 80 parts of tetrahydrofuran is applied on the previously formed intermediate layer by a dip coating method, and dried for 5 minutes to obtain a film thickness of 0.1 part.
A 28 μm charge generation layer was formed.

The obtained electrophotographic photosensitive member was charged, exposed and exposed.
It is installed in a regular development type plain paper copying machine in which the development-transfer-cleaning process is performed in a cycle of 0.8 seconds, and is continuously used in a low-temperature and low-humidity environment (15 ° C., 15% RH) for 10,000 hours.
A zero-image endurance test was performed. The evaluation was performed by measuring the dark potential (V _D ) at the initial stage, measuring the bright potential (V _L ) at the initial stage and after the durability test, and visually evaluating the obtained image. Table 2 shows the results. (Examples 13 to 21) An electrophotographic photoreceptor was prepared in the same manner as in Example 12, except that the solution for an intermediate layer used in Examples 2 to 10 was used.
evaluated. Table 2 shows the results. (Comparative Examples 7 to 10) Except for using the solution for the intermediate layer used in Comparative Examples 1 to 4,
An electrophotographic photosensitive member was prepared and evaluated in the same manner as in Example 12. Table 2 shows the results.

[0082]

[Table 2]

[0083]

As described above, according to the present invention, in all environments from low-temperature and low-humidity to high-temperature and high-humidity, it has stable and excellent potential characteristics and durability characteristics, and is excellent even when used repeatedly. An electrophotographic photosensitive member capable of continuously forming an image, a process cartridge having the electrophotographic photosensitive member, and an electrophotographic apparatus can be provided.

[Brief description of the drawings]

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

FIG. 2 shows an example of a block diagram of a facsimile having the electrophotographic photosensitive member of the present invention.

────────────────────────────────────────────────── ─── Continuation of the front page (72) Gen Miyazaki, inventor 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (56) References JP-A-57-151949 (JP, A) JP-A-2 -242265 (JP, A) JP-A-5-197321 (JP, A) JP-A-7-230174 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G03G 5/00 CA (STN)

Claims (5)

(57) [Claims] 1. An electrophotographic photosensitive member having a conductive support, an intermediate layer on the conductive support, and a photosensitive layer on the intermediate layer, wherein the intermediate layer is a repeating unit represented by the following formula (1) : ] (In the formula, A represents a tetravalent organic group, B represents a divalent organic group, R is. Represents a hydrogen atom or an alkyl group) an amic acid structure or an amic acid ester structure represented by
An electrophotographic photoreceptor comprising a copolymer having two or more types (provided that the repeating unit of the copolymer is
Combination of repeating units represented by formulas (A) and (B)
) . [Outside 2] (In the formula, A ₁ represents a divalent organic group, and R ₁ and R ₂ are the same.
One or different hydrogen atoms, substituted or unsubstituted al
A kill group, a substituted or unsubstituted alkoxyalkyl group and
Shows the micro substituted or unsubstituted aralkyl group, or R ₃
R ₇ is a hydrogen atom, a halogen atom, a substituted or unsubstituted
Alkyl group, a substituted or unsubstituted alkoxy group, a substituted
Or an unsubstituted aryl, nitro or cyano group
Show. ) [Outside 3] ( Wherein , A ₂ represents a divalent organic group, and R ₈ and R ₉ are the same)
One or different hydrogen atoms, substituted or unsubstituted al
A kill group, a substituted or unsubstituted alkoxyalkyl group and
Shows the micro substituted or unsubstituted aralkyl group, R ₁₀ is water
Elemental atom, halogen atom, substituted or unsubstituted alkyl
Group, substituted or unsubstituted alkoxy group, substituted or
Represents an unsubstituted aryl group, a nitro group and a cyano group;
₁₁ and R ₁₂ represent an alkyl group. ) 2. The electrophotographic photosensitive member according to claim 1, wherein the photosensitive layer has a charge generation layer and a charge transport layer. 3. An electrophotographic photoreceptor having a conductive support, an intermediate layer, a charge generation layer and a charge transport layer in this order.
2. The electrophotographic photosensitive member according to 2. 4. A process cartridge having an electrophotographic photosensitive member and at least one means selected from the group consisting of a charging means, a developing means and a cleaning means, wherein the electrophotographic photosensitive member is a conductive support, An intermediate layer on the body and a photosensitive layer on the intermediate layer, wherein the intermediate layer is represented by the following formula (1) as a repeating unit: (In the formula, A represents a tetravalent organic group, B represents a divalent organic group, R is. Represents a hydrogen atom or an alkyl group) an amic acid structure or an amic acid ester structure represented by
Containing a copolymer having 2 or more, the electrophotographic photoreceptor, and the at least one means being integrally supported, the process cartridge, which is a detachably attached to an electrophotographic apparatus main body (However, co Polymer
Is a repeating unit represented by the following formulas (A) and (B).
(Except for the combination of return units) . [Outside 5] (In the formula, A ₁ represents a divalent organic group, and R ₁ and R ₂ are the same.
One or different hydrogen atoms, substituted or unsubstituted al
A kill group, a substituted or unsubstituted alkoxyalkyl group and
Shows the micro substituted or unsubstituted aralkyl group, or R ₃
R ₇ is a hydrogen atom, a halogen atom, a substituted or unsubstituted
Alkyl group, substituted or unsubstituted alkoxy group, substituted
Or an unsubstituted aryl, nitro or cyano group
Show. ) [Outside 6] (In the formula, A ₂ represents a divalent organic group, and R ₈ and R ₉ are the same.
One or different hydrogen atoms, substituted or unsubstituted al
Kill group, a substituted or unsubstituted alkoxycarbonyl alkyl Le Moto及
And a substituted or unsubstituted aralkyl group, and R ₁₀ is water
Elemental atom, halogen atom, substituted or unsubstituted alkyl
Group, substituted or unsubstituted alkoxy group, substituted or
Represents an unsubstituted aryl group, a nitro group and a cyano group;
₁₁ and R ₁₂ represent an alkyl group. ) 5. An electrophotographic photoreceptor, charging means, exposure means,
An electrophotographic apparatus having a developing unit and a transfer unit, wherein the electrophotographic photosensitive member has a conductive support, an intermediate layer on the conductive support, and a photosensitive layer on the intermediate layer, wherein the intermediate layer is a repeating unit. The following equation (1) (In the formula, A represents a tetravalent organic group, B represents a divalent organic group, R is. Represents a hydrogen atom or an alkyl group) an amic acid structure or an amic acid ester structure represented by
An electrophotographic apparatus characterized by containing a copolymer having two or more kinds (provided that the repeating unit of the copolymer has the following formula:
Combinations of the repeating units shown in (A) and (B)
) . [Outside 8] (In the formula, A ₁ represents a divalent organic group, and R ₁ and R ₂ are the same.
One or different hydrogen atoms, substituted or unsubstituted al
Kill group, a substituted or unsubstituted alkoxycarbonyl alkyl Le Moto及
Shows the micro substituted or unsubstituted aralkyl group, or R ₃
R ₇ is a hydrogen atom, a halogen atom, a substituted or unsubstituted
Alkyl group, substituted or unsubstituted alkoxy group, substituted
Or an unsubstituted aryl, nitro or cyano group
Show. ) [Outside 9] (In the formula, A ₂ represents a divalent organic group, and R ₈ and R ₉ are the same.
One or different hydrogen atoms, substituted or unsubstituted al
A kill group, a substituted or unsubstituted alkoxyalkyl group and
And a substituted or unsubstituted aralkyl group, and R ₁₀ is water
Elemental atom, halogen atom, substituted or unsubstituted alkyl
Group, substituted or unsubstituted alkoxy group, substituted or
Represents an unsubstituted aryl group, a nitro group and a cyano group;
₁₁ and R ₁₂ represent an alkyl group. )