JPH04171457A - Electrophotographic sensitized body, and copying machine and facsimile using the same sensitized body - Google Patents

Abstract

PURPOSE:To obtain a stable potential characteristic and desirable images in all kinds of environment from low-temperature low-humidity to high-temperature high-humidity by containing a polymer or a copolymer, provided with specific unit elements, as main material in an intermediate layer. CONSTITUTION:In an electrophotographic sensitized body provided with a photosensitive layer on a conductive support body through an intermediate layer, the intermediate layer contains a polymer or a copolymer having unit elements expressed by a formula I. In the formula I, R<1> is a hydrogen atom or a low- grade alkyl group, R<2> is a substitutional or nonsubstitutional alkyl group, a substitutional or nonsubstitutional alkenyl group, a substitutional or nonsubstitutional aromatic ring, a substitutional or nonsubstitutional complex ring, or a substitutional or nonsubstitutional cycloalkyl group having an oxygen atom or a nitrogen atom in beta, gamma, delta positions in relation to a carbonyl group in the formula I. A stable potential characteristic is thereby displayed in all kinds of environment from low-temperature low-humidity to high-temperature high-humidity, and desirable images can be formed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to an electrophotographic photoreceptor, and more particularly to an improvement in an intermediate layer provided between a conductive support and a photosensitive layer.

[Prior Art] In general, in a Carlson type electrophotographic photoreceptor, stabilization of dark area potential and bright area potential is required to form an image with a constant image density and no fog when charging and exposure are repeated. Gender has become important.

To achieve this, an intermediate layer with functions such as improving charge injection from the support to the photosensitive layer, improving adhesion between the support and the photosensitive layer, improving coatability of the photosensitive layer, and covering defects on the support is developed. It has been proposed to provide a layer between the support and the photosensitive layer.

In addition, a layered structure in which the photosensitive layer is functionally separated into a charge generation layer and a charge transport layer has been proposed, but the charge generation layer is generally provided as an extremely thin layer, for example, about 0.5 μm. Defects, dirt, deposits, scratches, etc. on the surface of the support cause the thickness of the charge generation layer to be non-uniform. If the thickness of the charge generation layer is non-uniform, uneven sensitivity will occur in the photoreceptor, so it is required that the charge generation layer be made as uniform as possible.

For this reason, it has been proposed to provide an intermediate layer between the charge generating layer and the support, which functions as a barrier layer, an adhesive layer, and covers defects on the support.

Until now, polyamide (JP-A-46-47344, JP-A-52-25) has been used as a layer between the photosensitive layer and the support.
638, JP-A-58-95351), polyester (JP-A-52-20836, JP-A-54-26738)
No.), Boriurekun (Japanese Patent Application Laid-Open No. 10044-1982, No. 89435-1989), Casein (Japanese Patent Application Laid-Open No. 10-1989)
No. 3556), polypeptide (Japanese Unexamined Patent Publication No. 53-48523)
No.), polyvinyl alcohol (JP-A-52-10024
No. 0), polyvinylpyrrolidone (Japanese Patent Application Laid-open No. 48-3093
No. 6), vinyl acetate-ethylene copolymer (Japanese Patent Application Laid-open No. 1973-
26141), maleic anhydride ester polymer (JP 52-10138), polyvinyl butyral (JP 57-90639, JP 58-106549)
, quaternary ammonium salt-containing polymer (JP-A-51-12
6149, JP-A-56-60448), ethyl cellulose (JP-A-55-143564), and the like are known to be used.

[Problems to be Solved by the Invention] However, in an electrophotographic photoreceptor using the above-mentioned material as an intermediate layer, the resistance of the intermediate layer changes due to changes in temperature and humidity. It was difficult to always obtain stable potential characteristics and image quality with respect to the environment.

For example, if a photoconductor is used repeatedly under low temperature and low humidity conditions where the electrical resistance of the intermediate layer increases, charges remain in the intermediate layer, resulting in an increase in the bright area potential and residual potential, causing fog in the copied image or reversal phenomenon. When such a photoreceptor is used for blinking in an electrophotographic method, there are problems in that the density of the image becomes low and copies with a certain image quality cannot be obtained.

Furthermore, under high temperature and high humidity conditions, the barrier function decreases due to the lower resistance of the intermediate layer, and carrier injection from the support side increases, resulting in a decrease in dark area potential.

For this reason, the density of copied images becomes lighter under high temperatures, and when such a photoreceptor is used in an electrophotographic printer that performs a reversal phenomenon, black dot-like defects (black spots) may appear on the image. There were also problems such as easy fogging.

Therefore, an object of the present invention is to provide an electrophotographic photoreceptor that can provide stable potential characteristics and images in all environments ranging from low temperature and low humidity to high temperature and high humidity.

Another object of the present invention is to provide an electrophotographic photoreceptor that can form an intermediate layer that can sufficiently cover defects on a support, thereby forming good images without defects.

[Means for Solving the Problems] That is, the electrophotographic photoreceptor of the present invention is an electrophotographic photoreceptor in which a photosensitive layer is provided on a conductive support via an intermediate layer, and the intermediate layer has the following general formula [ It is characterized by containing a polymer or copolymer having the unit component shown in [1].

+cH2-C+ (wherein R' is a hydrogen atom or a lower alkyl group, R2 is a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl group,
substituted or unsubstituted aromatic ring, substituted or unsubstituted heterocycle, substituted or unsubstituted cycloalkyl group).

Table 1 shows examples of resins actually used in the present invention.

Table 1 The electrophotographic photoreceptor of the present invention contains the above-mentioned resin in the intermediate layer to prevent environmental changes such as an increase in residual potential at low temperatures and low humidity and a decrease in dark area potential due to a decrease in barrier function at high temperatures. It can be prevented.

The resin for the intermediate layer in the present invention does not cause much variation in volume resistivity under various environments, and when this resin is used as the intermediate layer, it is possible to obtain an electrophotographic photoreceptor with little variation in characteristics due to environmental changes. On the other hand, the resistance of ordinary resins used for the intermediate layer decreases by as low as three digits when moving from normal temperature to high temperature and high humidity, but the resin for the intermediate layer used in the present invention has a low resistance. Shows no change.

The resin used to create the intermediate layer constituting the electrophotographic photoreceptor of the present invention is prepared by dissolving a monomer corresponding to the unit component represented by the general formula [1] in an appropriate solvent, and adding azobisisobutyronitrile (AIBN) to the monomer corresponding to the unit component represented by the general formula [1]. ), it can be produced by adding a radical initiator such as benzoyl peroxide or an ionic polymerization initiator such as sodium metal to carry out the reaction.

Further, since impurities such as initiator residues often remain in the resin after production, it is preferable to add purification steps such as reprecipitation and washing before use.

Next, a specific production example of the resin example []] as the grafted polyamide resin used in the present invention will be shown.

<Production Example> 60 g of the following compound obtained by condensing methyl methacrylate and acetone in the presence of sodium methylate, 8 g of H3 H2-c'' AIB No. was dissolved in 100 g of methanol, and 7
The mixture was heated and stirred at 0° C. for 12 hours to carry out a polymerization reaction.

Next, 250 g of acetone was added to the reaction mixture cooled to room temperature.
After addition, reprecipitation purification was performed in demineralized water. Thereafter, vacuum drying was performed to obtain 28 g of resin (1).

The intermediate layer of the present invention has the above-mentioned resin (the following structural formula)% formula% 1 general formula [1] (wherein R1 is a hydrogen atom or a lower alkyl group, preferably a hydrogen atom or a methyl group, and R2 is a substituted or unsubstituted Substituted alkyl group, substituted or unsubstituted alkenyl group, substituted or unsubstituted aromatic ring, substituted or unsubstituted heterocycle, substituted or unsubstituted cycloalkyl group), if necessary, other It may be composed of a system to which fat, additives, conductive substances, etc. are added.

Here, examples of other resins to be added include polyamide resins such as copolymerized nylon and N-alkoxymethylated nylon, polyester resins, polyurethane resins, polyurea resins, and phenol resins.

Examples of additives include powders such as titanium oxide, alumina, and resins, surfactants, silicone leveling agents, silane coupling agents, and titanate coupling agents.

When using conductive substances, metal powders such as aluminum, copper, nickel, and silver, scaly metal powders, short metal fibers: conductive metal oxides such as antimony oxide, indium oxide, and tin oxide; polypyrrole, polyaniline, etc. , polymeric conductive materials such as polymer electrolytes; carbon fiber, carbon black, graphite powder, or conductive powder whose surface is coated with these conductive substances.

The thickness of the intermediate layer of the present invention is set in consideration of electrophotographic characteristics and defects on the support, and is 0.1 to 50 μm.
The thickness can be set up to about m, but it is usually 05 to 5 μm, and preferably 1 to 30 μm when a conductive substance is added.

The intermediate layer can be applied by dip coating, spray coating, roll coating, or the like.

Further, in the present invention, a second intermediate layer containing a resin as a main component can be provided on the intermediate layer as necessary for controlling barrier properties.

Examples of the resin material used for the second intermediate layer include polyamide resin, polyester resin, polyurethane resin, polyurea resin, and phenol resin.

The thickness of the second intermediate layer is preferably 0.1 to 5 μm, and can be coated by the same method as the above-mentioned intermediate layer.

In the present invention, the photosensitive layer may be of a single layer type or a laminated structure type in which functions are divided into a charge generation layer and a charge transport layer.

The charge generation layer of the laminated photoreceptor contains azo pigments such as Sudan red and Guianpuru, quinone pigments such as pyrenequinone and anthinthrone, quinocyanine pigments, benylene pigments, indigo pigments such as indigo and thioindigo, azlenium salt pigments, copper phthalocyanine, A charge generating material such as a phthalocyanine pigment such as titanyl oxophthalocyanine is dispersed in a solution containing a binder resin such as polyvinyl butyral, polystyrene, polyvinyl acetate, acrylic resin, polyvinyl pyrrolidone, ethyl cellulose, cellulose acetate butyrate, and this dispersion can be created by coating on the aforementioned intermediate layer.

The thickness of such a charge generation layer is 5 μm or less, preferably 0.05 to 2 μm.

The charge transport layer provided on the charge generation layer is a polycyclic aromatic compound having a structure such as biphenylene, anthracene, pyrene, or phenanthrene in the main chain or side chain, or a nitrogen-containing cyclic compound such as indole, carbazole, oxadiazole, or pyrazoline. It is formed using a coating liquid in which a charge transporting substance such as a compound, a hydrazone compound, or a styryl compound is dissolved in a resin having film-forming properties.

The reason for preparing the film in this manner is to compensate for the fact that charge transporting substances generally have a low molecular weight and are poor in film forming properties by themselves.

Examples of resins having such film-forming properties include polyester resins, polycarbonate resins, polymethacrylate resins, and polystyrene resins.

The thickness of the charge transport layer is 5 to 40 μm, preferably 10 to 3 μm.
It is 0 μm.

Further, in the present invention, an organic photoconductive polymer layer such as polyvinylcarbazole or polyvinylanthracene; a selenium vapor deposition layer, a selenium-tellurium vapor deposition layer, an amorphous silicon layer, etc. can also be used as the photosensitive layer.

In the present invention, as the structure of the photoconductive layer, in addition to the layer structure described above, a layer structure in which a charge generation layer is provided on a charge transport layer is also possible.

On the other hand, the conductive support used in the present invention may be any material as long as it has conductivity, such as a drum or sheet made of metal such as aluminum, copper, chromium, nickel, zinc, or corrosion-resistant steel (stainless steel). A conductive layer can be formed by laminating a metal foil such as aluminum or copper onto a plastic film, by vapor-depositing aluminum, indium oxide, tin oxide, etc. onto a plastic film, or by coating a conductive substance alone or with a suitable binder resin. Examples include plastic films and paper provided with

The conductive substances used in this conductive layer include metal powders such as aluminum, copper, nickel, and silver, metal foils, and short metal fibers; conductive metal oxides such as antimony oxide, indium oxide, and tin oxide; polypyrrole, polyaniline,
Polymer conductive materials such as polymer electrolytes: carbon fiber, carbon black, graphite powder; organic and inorganic electrolytes; or conductive powder whose surface is coated with these conductive substances.

Binder resins used in the conductive layer include polyamide resin, polyester resin, acrylic resin, polyamino acid ester resin, polyvinyl acetate resin, polycarbonate resin, polyvinyl formal, polyvinyl butyral, polyvinyl alkyl ether, polyalkylene ether, and polyurethane elastomer. Examples include thermosetting resins such as thermoplastic resins such as thermosetting resins, thermosetting polyurethanes, phenolic resins, and thermosetting epoxy resins.

The mixing ratio of conductive material and binder resin is 5:1 to 1:5
That's about it. This mixing ratio is determined in consideration of the electrical resistance value, surface properties, coating suitability, etc. of the conductive layer.

If the conductive substance is a powder, use a ball mill, roll mill,
A mixture is prepared and used in a conventional manner using a sand mill or the like.

In addition, other additives include surfactants, silane coupling agents, titanate coupling agents, silicone oil,
A silicone leveling agent or the like may also be added.

The electrophotographic photoreceptor of the present invention can be used not only in electrophotographic copying machines, but also in a wide range of electrophotographic applications such as laser beam printers, CRT printers, LED printers, liquid crystal printers, laser plate making, and facsimile printers. I can do it.

FIG. 1 shows a schematic configuration of a general transfer type electrophotographic apparatus using a drum type photoreceptor equipped with the electrophotographic photoreceptor of the present invention.

In FIG. 1, reference numeral 11 denotes a drum-type photoreceptor as an image bearing member, which is rotated at a predetermined circumferential speed in the direction of the arrow around a shaft 11a. During the rotation process, the photoreceptor 11 is uniformly charged to a predetermined positive or negative potential on its circumferential surface by the charging means 12, and then in the exposure section 13, it is exposed to a slit by an image exposure means (not shown). exposure, laser beam scanning exposure, etc.). As a result, electrostatic latent images corresponding to the exposed images are sequentially formed on the circumferential surface of the photoreceptor.

The electrostatic latent image is then developed with toner by the developing means 14,
The toner developed image is sequentially transferred by the transfer means 15 onto the surface of the transfer material P fed from a paper feeding section (not shown) in synchronization with the rotation of the photoreceptor 11 between the photoreceptor 11 and the transfer means 15. be done.

The transfer material P that has undergone the image transfer is separated from the photoreceptor surface, introduced into the image fixing means 18, where the image is fixed, and is printed out outside the machine as a copy.

After the image has been transferred, the surface of the photoreceptor 11 is cleaned by a cleaning means 16 to remove residual toner and is repeatedly used for image formation.

As the uniform charging means 12 for the photoreceptor 11, a corona charging device is generally widely used. In addition, as the transfer device 15, a corona transfer device is widely used (generally used). They may be constructed by being combined together as a unit, and this unit may be configured to be detachably attached to the main body of the apparatus.

For example, the photoreceptor 41 and the cleaning means 16 may be integrated into a single device unit, which can be attached and detached using guide means such as rails on the main body of the device. At this time, the above-mentioned device unit may be configured to include the charging means 12 and/or the developing means 14.

In addition, when an electrophotographic device that exposes a light image is used as a copying machine or a printer, the reflected light from the original, the transmitted light, or the original is read and converted into a signal, and this signal is used to scan the laser beam and drive the light emitting diode array. Alternatively, this may be performed by driving a liquid crystal shutter array or the like.

Furthermore, when used as a facsimile printer, the optical image exposure is exposure for printing received data. FIG. 2 is a block diagram showing an example of this case.

In FIG. 2, the controller 21 is the image reading section 2.
0 and printer 29. The entire controller 21 is controlled by a CPU 27. The read data from the image reading section is transmitted to the other party's station through the transmitting circuit 23.

Data received from the partner station is sent to the printer 29 through the receiving circuit 22. Image memory 26 stores predetermined image data. A printer controller 28 controls a printer 29. 24 is a telephone.

Images received from the line 25 (image information from a remote terminal connected via the line) are demodulated by the receiving circuit 22, and then decoded by the CPU 27 and sequentially stored in the image memory 26. Ru. Then, when one page worth of image information is stored in the image memory 26, the image information for that page is recorded. When the printer controller 28 receives the image information for one page from the CPTJ 27, it controls the printer 29 to record the image information for that page.
The next page is being received while the printer 29 is recording.

As described above, an electrophotographic apparatus equipped with the image holding member of the present invention can be used as a printer to receive and record images.

The present invention will be explained in more detail below by giving specific examples.

Example 1 50 parts of conductive titanium oxide powder (coated with tin oxide containing 10% antimony oxide), 25 parts of phenolic resin, 20 parts of methyl cellosolve, 5 parts of methanol, and silicone oil (polydimethylsiloxane-polyoxyalkylene copolymer) , average molecular weight 3000) 0.002 parts in diameter 1 m
A conductive layer coating material was prepared by mixing and dispersing the mixture for 2 hours in a sand mill device containing m glass beads.

Aluminum cylinder (outer diameter 30mm x length 260m)
m) The above paint was applied by dip coating and dried at 140° C. for 30 minutes to form a conductive layer with a thickness of 20 μm.

Next, 5 parts of the polymer (1) shown in Table 1 was added to 9 parts of methanol.
The mixture was dissolved in 5 parts to prepare a paint for forming an intermediate layer.

This paint was dip-coated on the conductive layer and heated at 100°C for 20 minutes.
It was dried for a minute to form an intermediate layer with a thickness of 0.5 μm.

Next, 3 parts of a disazo pigment with the following structural formula, 2 parts of polyvinylbenzal (benzalization rate 70%, weight average molecular weight 13000), and 35 parts of cyclohexanone.
After mixing and dispersing for 12 hours in a sand mill device containing glass beads with a diameter of 1 mm, methyl ethyl ketone (
A dispersion liquid for forming a charge generation layer was prepared by adding 60 parts of MEK. This dispersion was dip-coated onto each of the above intermediate layers and dried at 80° C. for 20 minutes to form a charge generation layer with a thickness of 0.15 μm.

Next, 10 parts of a styryl compound having the following structural formula and 10 parts of polycarbonate (weight average molecular weight 46,000) were dissolved in a mixed solvent of 20 parts of dichloromethane and 40 parts of monochlorobenzene, and this solution was dip-coated onto the above charge generation layer. This was dried at 120''C for 60 minutes to form a charge transport layer with a thickness of 18 μm.

The electrophotographic photoreceptor thus manufactured was attached to a reversal development type laser printer (the process of charging-exposure-development-transfer-cleaning is repeated in a 1.5-second cycle) at room temperature (23°C, 50% The electrophotographic properties were evaluated in a high temperature and high humidity environment (30° C., 85% RH).

As a result, as shown in Table 2, in the photoreceptor of Example 1,
The difference between the dark potential (v n) and the bright potential (■L) is large (
In addition to obtaining sufficient potential contrast, the dark area potential (VD) was stable even under high temperature conditions, and good images with no defects on black spots (black spots) or fog were obtained.

Examples 2 to 5 Polymer (2) exemplified in Table 1 as a paint for forming an intermediate layer
, (4), (6) or (8), respectively.
Electrophotographic photoreceptors were manufactured in the same manner as in Example 1, and named as Examples 2 to 5, respectively.

When each of these photoreceptors was evaluated in the same manner as in Example 1, the dark potential (V, ) was stable even under high temperature conditions, and good images were obtained with no defects on sunspots (black spots) or fog. The results are shown in Table 2.

Comparative Example 1 As a paint for forming an intermediate layer, N-methoxymethylated 6-nylon (weight average molecular weight 150,000, methoxymethyl group substitution rate 28%) was used instead of resin (1) illustrated in Table 1.
An electrophotographic photoreceptor was manufactured in the same manner as in Example 1 except that the following was used.

When this photoreceptor was evaluated in the same manner as in Example 1, the charging ability deteriorated under high temperature and high humidity conditions, and the dark area potential (V o )
A decrease in image quality was observed, and defects on black spots (black spots) began to appear on the image.

The results are shown in Table 2.

Example 6 A paint for forming an intermediate layer was prepared by dissolving 5 parts of the resin (3) shown in Table 1 in 95 parts of methanol.

This paint was dip-coated onto an aluminum cylinder (outer diameter 30 mm x length 360 μm) and dried at 100° C. for 20 minutes to form an intermediate layer with a thickness of 1.0 μm.

Next, a type chichnylphthalocyanine pigment 4 with the following structural formula
1 part, 2 parts of polyvinyl butyral (butyralization rate 68%, weight average molecular weight 24,000) and 34 parts of cyclohexanone
After mixing and dispersing for 100 hours in a sand mill device containing glass beads with a diameter of 1 mm, tetrahydrofuran (T
A dispersion liquid for forming a charge generation layer was prepared by adding 60 parts of HF). This dispersion was dip coated onto each of the above intermediate layers and dried at 80° C. for 20 minutes to form a charge generation layer with a thickness of 0.2 μm.

Next, 10 parts of the styryl compound used in Example 1 and 10 parts of polycarbonate (weight average molecular weight 63,000) were dissolved in a mixed solvent of 15 parts of dichloromethane and 45 parts of monochlorobenzene, and this solution was applied onto the above charge generation layer. Dip coating and drying at 120°C for 60 minutes to achieve a film thickness of 25
A charge transport layer of μm was formed.

The electrophotographic photoreceptor produced in this manner was transferred to a copying machine (charging-exposure-development-transfer-cleaning process to 1.0
(repeated in second cycles).

This photoconductor was tested under low temperature and low humidity (15°C, 115%RH).
), the electrophotographic characteristics were evaluated in the environment shown in Table 2.
As shown in FIG. 2, in this photoreceptor, the difference between the dark area potential (VD) and the light area potential (VL) was large, and sufficient potential contrast was obtained. Furthermore, when 1000 images were continuously produced, stable images were obtained with little increase in bright area potential (VL).

Examples 7 to 10 As a paint for forming an intermediate layer, polymer resins (
Electrophotographic photoreceptors were manufactured in the same manner as in Example 6 except that 9), (5), (7), or (11) were used, respectively, to give Examples 7 to 10, respectively.

When each of these photoreceptors was evaluated in the same manner as in Example 6, the difference between the dark area potential (V O) and the dark area potential (VL) was large for each photoreceptor, and sufficient potential contrast was obtained, as well as continuous Even after printing 1000 images, stable images were formed with little increase in bright area potential (VL). The results are shown in Table 3.

Comparative Example 2 Electrophotography was carried out in the same manner as in Example 6, except that alcohol-soluble copolymerized nylon (weight average molecular weight 81,000) was used instead of resin (3) shown in Table 1 as the paint for forming the intermediate layer. A photoreceptor was manufactured as Comparative Example 2.

When this photoreceptor was evaluated in the same manner as in Example 6, it was found that the bright area potential (VL) increased after 1000 continuous sheets were printed, causing fog on the image.

The results are shown in Table 2.

Example 11 30 parts of conductive titanium oxide powder (coated with tin oxide containing 10% antimony oxide), 2 parts of rutile formate powder
0 parts, 20 parts of the polymer [10] illustrated in Table 1, 20 parts of methanol, and 10 parts of 2-propertool were mixed and dispersed for 1 hour in a sand mill containing glass beads with a diameter of 1 mm to prepare a coating material for a conductive layer. was prepared.

Aluminum cylinder (outer diameter 60 mm x length 2
60mm), apply the above paint by dip coating and heat it at 160℃ for 30 minutes.
It was dried for minutes to form an intermediate layer with a thickness of 16 μm.

Next, 5 parts of alcohol-soluble copolymerized nylon (weight average molecular weight 75,000) was dissolved in 95 parts of methanol, and after coating on the above intermediate layer by dip coating, it was dried at 80°C for 10 minutes to form a second layer with a film thickness of 0.3 μm. An intermediate layer was formed.

Next, 2 parts of a disazo pigment with the following structural formula, 1 part of polyvinyl butyral (butyral conversion rate 72%, weight average molecular weight 18,000) and 30 parts of cyclohexanone.
After mixing and dispersing for 244 hours in a sand mill device containing glass beads with a diameter of 1 mm, methyl ethyl ketone (
A dispersion liquid for forming a charge generation layer was prepared by adding 65 parts of MEK. This dispersion was dip coated onto the second intermediate layer and
It was dried at .degree. C. for 20 minutes to form a charge generation layer with a thickness of 0.25 .mu.m.

Next, 11 parts of a hydrazone compound of the following structural formula and 12 parts of polycarbonate (weight average molecular weight 46,000) were dissolved in a mixed solvent of 20 parts of dichloromethane and 40 parts of monochlorobenzene, and this solution was dip-coated onto the above charge generation layer. Then, it was dried at 120° C. for 60 minutes to form a charge transport layer with a thickness of 204 zm.

The electrophotographic photoreceptor produced in this manner was transferred to a copying machine (charging-exposure-development-transfer-cleaning process of 0.8
(repeated in second cycles).

For this photoreceptor, under low temperature and low humidity (15°C, 10%RH)
When the electrophotographic characteristics were evaluated in an environment of Furthermore, when 1000 images were printed in succession, stable images were obtained with little increase in bright area potential (L).

The results are shown in Table 4.

Example 12 An electrophotographic photoreceptor of Example 12 was manufactured by forming an intermediate layer, a charge generation layer, and a charge transport layer in the same manner as in Example 11 except that the second intermediate layer was not provided.

When this photoreceptor was evaluated in the same manner as in Example 11,
The difference between the dark area potential (V O) and the light area potential (V L) is large, sufficient potential contrast is obtained, and continuous 10
Even when 00 images were produced, stable images were obtained with little increase in bright area potential (VL). The results are shown in Table 4.

Comparative Examples 3 and 4 An electrophotographic photoreceptor was prepared in the same manner as in Examples 11 and 12, except that an enol resin was used as the coating resin for the intermediate layer containing conductive titanium oxide powder and rutile-type titanium oxide powder. were produced and designated as Comparative Examples 3 and 4, respectively.

When each of these photoreceptors was evaluated in the same manner as in Example 11, it was found that in Comparative Example 3, the bright area potential (VL) increased after 1000 continuous sheets were printed, and fog appeared on the image. In addition, in Comparative Example 4 in which a charge generation layer and a charge transport layer were provided directly on the intermediate layer, the barrier properties of the intermediate layer were insufficient, the charge injection from the support side was large, and the dark potential (
(2) Due to the low Il+), the potential contrast necessary for image formation could not be obtained. The results are shown in Table 3.

Table 2 Table 3 Table 4 [Effects of the Invention] The electrophotographic photoreceptor of the present invention contains the above polymer or copolymer resin in the resin for forming an intermediate layer between the conductive support and the photosensitive layer. By containing , stable potential characteristics can be exhibited in all environments ranging from low temperature and low humidity to high temperature and high temperature, and a good image can be formed.

[Brief explanation of drawings]

FIG. 1 is a schematic sectional view of a transfer type copying machine equipped with the electrophotographic photoreceptor of the present invention, and FIG. FIG. 2 is a block diagram of a facsimile system in which a secondary photographic photoreceptor is used as a printer. [Main symbols in the figure] l...Drum type photoreceptor 12...Charging means 13...Exposure section 14...Developing means 15...Transfer means 16...Cleaning means 18...・Image fixing means L...Light image exposure P...Transfer material agent Patent attorney Johei Yamashita

Claims (1)

[Scope of Claims] (1) In an electrophotographic photoreceptor having a photosensitive layer on a conductive support via an intermediate layer, the intermediate layer has the following general formula [1]
An electrophotographic photoreceptor characterized by containing as a main material a polymer or copolymer having a unit component represented by: ▲There are mathematical formulas, chemical formulas, tables, etc.▼General formula [1] is a hydrogen atom or a lower alkyl group, R^2 is a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted aromatic ring, a substituted or unsubstituted heterocycle,
(represents a substituted or unsubstituted cycloalkyl group). (2) The electrophotographic photoreceptor according to claim 1, wherein the intermediate layer contains a conductive substance. (3) An electrophotographic apparatus comprising an electrophotographic photoreceptor, a latent image forming means, a means for developing the formed latent image, and a means for transferring the developed image to a transfer material, wherein the electrophotographic photoreceptor is the one according to claim 1. An electrophotographic device characterized by being as described in . (5) The electrophotographic photoreceptor according to claim 1 and at least one of the charging means, the developing means, and the cleaning means are integrally supported to form a unit, and the single unit is detachably attached to the main body of the apparatus. Characteristic equipment unit. (6) An electrophotographic apparatus comprising the electrophotographic photoreceptor according to claim 1, a latent image forming means, a means for developing the formed latent image, and a means for transferring the developed image onto a transfer material. (7) The electrophotographic photoreceptor according to claim 1, an electrophotographic apparatus comprising a latent image forming means and a means for transferring a developed image to a transfer material, and a receiving means for receiving image information from a remote terminal. A facsimile machine featuring