JPH04170552A - Electrophotosensitive material and copying machine and facsimile using this material - Google Patents

Abstract

PURPOSE:To obtain stable potential characteristic and a good picture in all environments reaching under a high temperature high humidity from under a low temperature low humidity by using resin, which contains grafted polyamide resin containing a specific graft component, as an intermediate layer interposed between a supporter and a sensitive layer. CONSTITUTION:An intermediate layer contains polyamide resin having a unit component expressed by a formula I. In the formula, R<1> represents a hydrogen atom or a low class alkyl group, and R<2> represents substituted or not alkyl group, substituted or not alkenyl group, substituted or not aromatic circle, substituted or not heterocycle, substituted or not cycloalkyl group, having an O atom or an N atom in beta, gamma, delta places relating to a carbonyl group in the formula I. Here by providing grafted polyamide resin in the intermediate layer, environmental fluctuation such as decrease of dark part potential by increase of residual potential at a low temperature low humidity and by decrease of a barrier function under a high temperature high humidity can be prevented. In this way, stable potential characteristic and picture are obtained relating to all environments reaching under high temperature high humidity from under low temperature low humidity.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an electrophotographic photoreceptor, and more specifically, to an electrophotographic photoreceptor provided between a conductive support (hereinafter referred to as "support") and a photosensitive layer. Concerning improvements to the intermediate layer.

[Prior Art] In general, in Carlson type electrophotographic photoreceptors, the stability of dark area potential and bright area potential is important in forming a constant image density and fog-free image when charging and exposure are repeated. It has become.

To achieve this, an intermediate layer has 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. 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, with a thickness of 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)
), polyurethane (JP-A-49-10044, JP-A-53-89435), casein (JP-A-55-10)
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 interposed between a support and a photosensitive layer, the resistance of the intermediate layer changes due to changes in temperature and humidity. However, it was difficult to always obtain stable potential characteristics and image quality in all environments, from low temperature and low humidity to high temperature and high humidity.

For example, if a photoreceptor is used repeatedly under low temperature and low humidity conditions, where the electrical resistance of the intermediate layer is high, charges remain in the intermediate layer, resulting in an increase in bright area potential and residual potential, which may cause fogging or inversion of copied images. When such a photoreceptor is used in an electrophotographic printer that performs development, there are problems in that the image density becomes low and copies with a certain image quality cannot be obtained.

Furthermore, when exposed to high temperatures, 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 the copied image becomes thinner under high temperature conditions, and when such a photoreceptor is used in an electrophotographic printer that performs reversal development, the image may have black dot-like defects (black spots). Also, there was a problem that fogging was likely to occur.

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 in which a good defect-free image can be obtained by forming an intermediate layer that can sufficiently cover defects on a support.

[Means for Solving the Problems] 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 is represented by the general formula [1]. It is characterized by containing a polyamide polar resin having the unit components shown.

(In the formula, R' is a hydrogen atom or a lower alkyl group, and R2 is β to the carbonyl group in general formula (1).

Substituted or unsubstituted alkyl group, substituted or unsubstituted alkenyl group, substituted or unsubstituted aromatic ring, substituted or unsubstituted heterocycle, substituted or unsubstituted cycloalkyl group having an O or N atom at the γ or δ position) .

The grafted polyamide resin of the present invention is a grafted polyamide resin produced by grafting a polymer or copolymer formed from unit components represented by the general formula [1] obtained by polymer reaction onto the main chain of the polyamide resin. It is a polyamide resin.

Polyamide resins constituting the main chain of the grafted polyamide used in the present invention include 6-nylon, 11-nylon, 12-nylon, 6.6-nylon, 6.
Examples include various nylon resins such as 10-nylon, copolymerized nylon resins containing the above components, N-alkoxymethylated or N-alkylated nylon resins, and nylon resins containing aromatic components.

On the other hand, the component constituting the graft side chain has the aforementioned general formula (I
) may be a single polymer or a copolymer with other copolymerizable compounds. In the case of a copolymer, the composition of the unit component of general formula (1) in the graft side chain is 50 m
It is preferably 1% or more, more preferably 70
The mo is 1% or more.

The content of the grafted portion in the grafted polyamide resin is preferably in the range of 10 to 70 wt%, particularly 15 to 50 wt%.

Further, the grafted polyamide used in the present invention may be crosslinked and used in consideration of solvent resistance to the coating material for the photosensitive layer. Crosslinking is usually carried out using an epoxy compound, a melamine compound, etc. by heat treatment after the coating is formed. When N-alkoxymethylated nylon resin is used as the polyamide component, self-crosslinking can be achieved by heating without using a crosslinking agent, using an acid catalyst such as citric acid, adipic acid, tartaric acid, maremonosun, or hypophosphorous acid. A crosslinked body can also be formed by.

The main chain component of the polyamide resin used in the present invention is, for example, a polymer having a structure such as CHiOCHs as a unit component, or a polymer having two or more of these structures as a unit component. Examples include copolymers with Specific examples of such main chain components are shown below.

Examples of components of polyamide resin beads Next, examples of grafted polyamide resins actually used in the present invention will be shown.

Toto 9■ The electrophotographic photoreceptor of the present invention contains the above-mentioned grafted polyamide resin in the intermediate layer, thereby increasing the residual potential at low temperature and low humidity and lowering the dark area potential due to a decrease in barrier function at high temperature and high temperature. environmental changes can be prevented.

The grafted polyamide resin in the present invention does not cause much variation in volume resistivity under various environments. Therefore, when this resin is used as an intermediate layer, it is possible to obtain an electrophotographic photoreceptor with little change in resistance due to environmental changes.Resistance of ordinary polyamide resins decreases by three digits when exposed to normal temperature to high temperature and high humidity. However, grafted polyamide resins do not show any major changes.

The reason why the grafted polyamide resin is less susceptible to environmental changes is not clear, but the following structural factors may be considered.

(1) By bonding graft chains, it is easier to become amorphous or mesh than a linear polymer when forming a coating film, and it is easier to retain conductive substances such as water or ions retained inside.

(2) Water, ionic substances, etc. are easily adsorbed due to the polar groups of the graft portion.

The grafted polyamide resin used in the present invention can be prepared by grafting a monomer corresponding to the unit component represented by general formula (I) to the main chain polyamide resin by polymer reaction.

Although the polyamide resin that is the main chain is not particularly limited, it is necessary that the graft portion is polymerized (formed) due to its structure.

In general, it is known that the methine or methylene group in contact with the N atom of the amide bond has a high degree of activity, is strong, and is likely to cause radicalization, and the polyamide resin used in the present invention also has a main chain Those having a proton on the upper carbon atom are preferred.

In the polymer reaction for grafting, the main chain polyamide resin and the monomer serving as the graft component are dissolved in a suitable solvent that dissolves both the polyamide resin and the monomer, and azobisisobutyronitrile (AIBN), peroxybenzoyl A grafted polyamide resin can be produced by adding a radical initiator such as or an ionic polymerization initiator such as metallic Na.

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

Next, a specific synthesis example of the resin example (3) as the grafted polyamide resin used in the present invention will be shown.

Production example> 6-12-66-610 quaternary copolymerized nylon (weight composition ratio: 6/12/66/610 = 2/1/2/2,
Weight average molecular weight: 140,000) 2 g of IO, 9.8 g of a compound represented by the following general formula, and 0.0002 g of AIBN were dissolved in 120 g of methanol, and the mixture was heated and stirred at 40°C for 3 hours to initiate a graft reaction. Next, the reaction mixture solution cooled to room temperature was diluted with 160 g of methanol, and this was mixed with 2.0 kg of methyl ethyl ketone (Mf:K), 1 part of n-hexane.
．． It was dropped into 2 kg of mixed solvent to obtain a white precipitate of grafted polyamide. This precipitate was collected by filtration, washed three times with 600 g of MEK on a filter paper, filtered, and dried under reduced pressure at 35° C. for 6 hours to obtain 15.6 g of resin [3].

The intermediate layer of the present invention is as described above. ~←CH2-C10- ■ 〇　　　　　　　General formula [1] is β with respect to the carbonyl group in general formula (1).

Indicates a substituted or unsubstituted alkyl group, substituted or unsubstituted alkenyl group, substituted or unsubstituted aromatic ring, substituted or unsubstituted heterocycle, substituted or unsubstituted cycloalkyl group having an O atom or N atom at the γ or δ position ) alone, or may be composed of a system in which other resins, additives, and conductive substances are added as necessary.

Examples of other resins added here include copolymerized nylon,
Examples include polyamides such as N-alkoxymethylated nylon, polyesters, polyurethanes, polyureas, and phenolic resins. Examples of additives include powders such as titanium oxide, alumina, and resins, surfactants, silicone leveling agents, silane coupling agents, and titanate coupling agents.

Examples of conductive substances include metal powders, metal powders, and short metal fibers such as aluminum, copper, nickel, and silver; conductive metal oxides such as antimony oxide, indium oxide, and tin oxide; polypyrrole, polyaniline, and polymers. Polymer conductive materials such as electrolytes.

Examples include 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
Although the thickness can be set up to about .mu.m, it is usually 0.5 to 5 .mu.m, and preferably 1 to 30 .mu.m 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 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 this second intermediate layer include polyamide, polyester, polyurethane, polyurea, phenol resin, etc. in addition to the polyamide of general formula (I).

The thickness of this second intermediate layer is preferably 0.1 to 5 μm, and is 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 a charge generation layer and a charge transport layer are separated in function.

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, perylene pigments, indigo pigments such as indigo and thioindigo, raw materials for azulenium salts, copper phthalocyanine, A charge generating material such as a phthalocyanine pigment such as titanyl oxophthalocyanine is dispersed in a binder resin such as polyvinyl butyral, polystyrene, polyvinyl acetate, acrylic resin, polyvinyl pyrrolidone, ethyl cellulose, cellulose acetate butyrate, and this dispersion is used as described above. It can be formed by coating on the intermediate layer. The thickness of such a charge generation layer is 5 tLm 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 ring such as indole, carbazole, oxadiazole, or pyrazoline. It is formed using a coating liquid in which a charge-transporting substance such as a compound of the formula formula, a hydrazone compound, or a styryl compound is dissolved in a resin having film-forming properties. The reason why it is formed in this way is that the charge transporting substance generally has a low molecular weight and has poor film-forming properties by itself.

Examples of resins with such film-forming properties include polyester,
Examples include polycarbonate, polymethacrylic ester, and polystyrene.

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 support used in the present invention may be any material as long as it has conductivity, such as aluminum, copper,
Metals such as chromium, nickel, zinc, and stainless steel molded into drums or sheets; metal foils such as aluminum and copper laminated on plastic films; and plastic films with aluminum, indium oxide, tin oxide, etc. vapor-deposited on them. Alternatively, examples include metal, plastic film, paper, etc. in which a conductive layer is provided by applying a conductive substance alone or together with a suitable binder resin.

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 gold oxides such as antimony oxide, indium oxide, and tin oxide; Examples include conductive polymer materials such as volivirol, polyaniline, and polymer electrolytes: carbon fiber, carbon black, and graphite powder; organic and inorganic electrolytes; and conductive powders whose surfaces are coated with these conductive substances.

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

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 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 applied to general electrophotographic devices such as copying machines, laser printers, LED printers, and liquid crystal shutter type printers. It can also be widely applied to devices such as plate making and facsimile machines.

The present invention will be explained in more detail below with reference to specific examples.

Fuse ■ 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) Combined, average molecular weight 3000) 0.1)02 parts φ
A coating material for a conductive layer was prepared by mixing and dispersing the mixture for 2 hours using a sand mill device using 1.1 glass beads.

Aluminum cylinder (φ30mm x 260mm
), the above paint was applied by dip coating and dried at 140°C for 30 minutes to form a conductive layer with a film thickness of 2Q/im.

Next, 1 part and 5 parts of the polymer shown in Table 1 above was dissolved in 95 parts of methanol to prepare a paint for the intermediate layer.

This paint was applied by dip coating onto the conductive layer and heated to 100℃ for 1 hour.
It was dried for 5 minutes to form an intermediate layer with a thickness of 0.8 μm.

Next, 3 parts of the disazo pigment of the structural formula, 2 parts of polyvinylbenzal (benzalization rate 75%, weight average molecular weight 25,000) and 35 parts of cyclohexanone were dispersed for 20 hours in a sand mill apparatus using φ1 mm glass beads, and then methyl ethyl ketone was dispersed. (MEK)
A dispersion liquid for a charge generation layer was prepared by adding 60 parts. 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 the styryl compound of the structural formula and 0 parts of polycarbonate (weight average molecular weight 52,000) were dissolved in a mixed solvent of 20 parts of dichloromethane and 40 parts of monochlorobenzene, and this solution was applied by dip coating onto the above charge generation layer. 12
It was dried at 0° C. for 60 minutes to form a charge transport layer with a thickness of 18 μm.

The electrophotographic photoreceptor produced in this way was attached to a reversal development type laser printer that repeats the process of charging, exposing, developing, transferring, and cleaning in a 1.5-second cycle. ) and high temperature environments (30° C., 85% RH).

As a result, as shown in Table 2, in the photoreceptor of Example 1,
The difference between the dark area potential (V O) and the light area potential (vL) is large,
Sufficient potential contrast was obtained, the dark area potential (■.) was stable even under high temperature and high humidity, and good images were obtained without defects on black spots (black spots) or fog.

Polymer resin (5) exemplified in Table 1 as a paint for the intermediate layer,
Electrophotographic photoreceptors were produced in the same manner as in Example 1 except that (10), (14), and (21) were used, respectively, to give Examples 2 to 5, respectively.

When these photoreceptors were evaluated in the same manner as in Example 1, the dark potential (Vo) of all of them was stable even under high and high temperatures.
A good image was obtained with no defects on black spots (black spots) or fog.

The results are shown in Table 2.

Instead of the above-mentioned polyamide resin as a paint for the LL medical intermediate layer,
N-methoxymethylated nylon 6 (weight average molecular weight 13
An electrophotographic photoreceptor was produced in the same manner as in Example 1, and used as Comparative Example 1, except that 0000 and methoxymethyl group substitution ratio of 28% were used.

When this photoreceptor was evaluated in the same manner as in Example 1, it was found that under high temperature and high humidity conditions, the charging ability deteriorated, the dark area potential (vo) decreased, and there were defects on the image (black spots). started to occur.

The results are shown in Table 2.

Five parts of the polymer resin [28] listed in Table 1 of K Gojo was dissolved in 95 parts of methanol to prepare a paint for the intermediate layer.

Apply this paint to an aluminum cylinder (φ30mm
360m+n) and coated with 11[cm] at 100"
It was dried for 5 minutes to form an intermediate layer with a thickness of 1.5 μm.

Next, JP-A No. 61-239248 (correspondence: USP
, 4 parts of titanyl phthalocyanine pigment obtained according to the production example disclosed in Patent No. 4,728,592), 2 parts of polyvinyl butyral (butyral conversion rate: 68%, weight average molecular weight: 32,000), and 34 parts of cyclohexanone. After dispersing for 20 hours in a sand mill device using φ1 mm glass beads, tetrahydrofuran (THF
) to prepare a dispersion for a charge generation layer. This dispersion was dip coated onto each of the above intermediate layers, and
C for 15 minutes to form a charge generation layer with a thickness of 0.15 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, drying at 120'C for 60 minutes, film thickness 20
A charge transport layer of .mu.m was formed.

The electrophotographic photoreceptor thus produced was attached to a copying machine in which a process of charging, exposure, development, transfer, and kneading was repeated in a 1.5 second cycle.

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 consecutive images were produced, stable images were obtained with little increase in bright area potential (vL).

K5 Medical 2211 Polymer resin (3) exemplified in Table 1 as a paint for the intermediate layer,
Electrophotographic photoreceptors were produced in the same manner as in Example 6, except that polyamide resins (7), (18), and (3o) were used, respectively, to give Examples 7 to 10, respectively.

When these photoreceptors were evaluated in the same manner as in Example 6, all photoreceptors had a dark area potential (vo) and a bright area potential (VL).
), and sufficient potential contrast can be obtained, and even if 1000 consecutive images are produced, the bright area potential (
A stable image was obtained with a small increase in V t, ).

The results are shown in Table 3.

As an intermediate layer paint, instead of the polyamide resin mentioned above,
Alcohol-soluble copolymerized nylon (weight average molecular weight 70
An electrophotographic photoreceptor was produced as Comparative Example 2 in the same manner as in Example 6, except that 0(10) was used.

When this photoreceptor was evaluated in the same manner as in Example 6, the bright area potential (VL) increased after repeating 1000 consecutive sheets.
Fog started to appear on the image.

The results are shown in Table 3.

35 parts of conductive titanium oxide powder coated with tin oxide containing 10% antimony oxide, 30 parts of rutile-type titanium oxide powder, polymer resin (4) as exemplified in Table 1 above. 20 parts of methanol, and 10 parts of 2-propanol were mixed and dispersed for 2 hours in a sand mill using a φ-sized glass bead to prepare a coating material for a conductive layer.

Aluminum cylinder (φ60 mm x 260 m
The above coating material was dip-coated onto (n+) and dried at 160° C. for 30 minutes to form an intermediate layer with a thickness of 16 μm.

Next, 5 parts of alcohol-soluble copolymerized nylon (weight average molecular weight 60,000) was dissolved in 95 parts of methanol,
After dip coating on the above intermediate layer, it was dried at 80° C. for 20 minutes to form a second intermediate layer having a film thickness of 0.5 LLm.

Next, 2 parts of the disazo pigment of the structural formula, 1 part of polyvinyl butyral (butyralization rate 78%, weight average molecular weight 19000) and 30 parts of cyclohexanone were dispersed for 20 hours in a sand mill device using φ1 mm glass beads, and then methyl ethyl ketone was dispersed for 20 hours. A dispersion liquid for a charge generation layer was prepared by adding 65 parts of (MEK). This dispersion was dip coated onto the second intermediate layer and dried at 80° C. for 15 minutes to form a charge generation layer with a thickness of 0.15 μm.

Next, 10 parts of the hydrosizone compound having the structural formula and 10 parts of polycarbonate (weight average molecular weight 52,000) were dissolved in a mixed solvent of 20 parts of dichloromethane and 40 parts of monochlorobenzene, and this solution was applied by dip coating onto the above charge generation layer. , 12
It was dried at 0° C. for 60 minutes to form a charge transport layer with a thickness of 18 μm.

The electrophotographic photoreceptor thus produced was attached to a copying machine in which a process of charging, exposure, development, transfer, and cleaning was repeated in a 1.0 second cycle.

For this photoreceptor, under low temperature and low humidity (10℃, 10%RH)
When the electrophotographic characteristics were evaluated in an environment of Ta. Furthermore, when 1000 images were continuously produced, stable images were obtained with little increase in bright area potential (VL).

The intermediate layer, charge generation layer and charge transport layer were formed from the base material side in the same manner as in Example 11 except that the second intermediate layer was not provided, and the electrophotographic photoreceptor of Example 12 was prepared. Manufactured.

When this photoreceptor was evaluated in the same manner as in Example 11,
The difference between the dark area potential (V O) and the bright area potential (fvL) is large, and sufficient potential contrast is obtained and continuous 1
Even after producing 000 images, stable images were obtained with little increase in bright area potential (VL). The results are shown in Table 4.

The same as in Examples 11 and 12 except that a phenolic resin was used instead of the polyamide resin as the paint for the intermediate layer containing the electrically conductive titanium oxide powder and the rutile-type titanium oxide powder. Electrophotographic photoreceptors were produced as Comparative Examples 3 and 4, respectively.

When this photoreceptor was evaluated in the same manner as in Example 11,
In Comparative Example 3, the bright area potential (V
L) increased, 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 property of the intermediate layer was insufficient, and the charge injection from the support side was large (the dark potential (V) was low). Therefore, the potential contrast necessary for image formation could not be obtained.

The results are shown in Table 4.

Table 2 Table 3 Table 4 [Effects of the Invention] The electrophotographic photoreceptor of the present invention has a graft containing the graft component of general formula (I) as an intermediate layer interposed between the support and the photosensitive layer. By using a resin containing a polyamide resin that oxidizes, stable potential characteristics and good images can be formed in all environments from low temperature and low humidity to high temperature and high temperature.

[Brief explanation of drawings]

FIG. 1 is a schematic sectional view of a transfer copying machine equipped with the electrophotographic photoreceptor of the present invention, and FIG. 2 is a block diagram of a facsimile system using the electrophotographic photoreceptor of the invention as a printer. [Main symbols in the diagram] 11...Drum type photoreceptor 12...Charging means 13...Exposing section 14...Developing means 15...Transfer means 16...Cleaning means 18... Image fixing means L...Light image exposure P...Transfer material agent Patent attorney Sekihei Yamashita

Claims (8)

[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 a polyamide resin having a unit component represented by , R^2 is a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted aromatic group having an oxygen atom or nitrogen atom at the β, γ, or δ position relative to the carbonyl group in the general formula [1] group ring, substituted or unsubstituted heterocycle, substituted or unsubstituted cycloalkyl group). (2) The electrophotographic photoreceptor according to claim 1, wherein the intermediate layer contains a conductive substance. (3) The electrophotographic photoreceptor according to claim 1 or 2, wherein the conductive support comprises a support base and a conductive layer provided thereon containing a conductive substance and a binder resin. (4) 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) A facsimile machine comprising an electrophotographic apparatus including the electrophotographic photoreceptor according to claim 1 and a receiving means for receiving image information from a remote terminal. (6) 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. (7) 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. (8) 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