JPH0339965A - Electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To enhance mobility of electric charge and heat resistance and adhesion and to reduce defects by forming a charge transfer layer made of an organic polymer compd. obtained by dispersing a metal powder or conductive metal oxide powder into the polymer. CONSTITUTION:The electrophotographic sensitive body is formed by successively laminating on a substrate 1 the charge transfer layer 2 and a charge generating layer 3, and the layer 2 is made of the org. polymer compd. containing in a dispersed state the powder of the metal preferably, selected from elements of groups IIa, IIb, and IIIa of a periodic table, and the transition elements, and the like or the oxide powder of the metal, preferably, such as, tin, zinc, antimony, titanium, or indium, thus permitting photocarriers generated at the charge generating layer 3 to be efficiently transferred to the side of the substrate 1, and charge transfer function, adhesion, mechanical strength, and hardness to be enhanced.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to an electrophotographic photoreceptor, particularly an electrophotographic photoreceptor having a functional molecule Il type photosensitive layer.

(Prior Art) Conventionally, the photosensitive layer of an electrophotographic photoreceptor is of a so-called functionally separated type, which is separated into a charge generation layer that generates charge carriers by irradiation with light and a charge transport layer that efficiently moves these charge carriers. Both organic and inorganic materials have been used as charge transport materials in photoreceptors. As the organic material, there are those using a high molecular compound such as polyvinylcarbazole, or those using a low molecular compound such as pyrazoline or triphenylamines dispersed or melted in a high molecular binder resin such as polycarbonate. Typical inorganic materials include selenium and chalcogenide compounds such as selenium/tellurium.

(Problems to be Solved by the Invention) However, in electrophotographic photoreceptors using these charge transport materials, electrical repeatability characteristics such as chargeability, dark decay, and residual potential are unstable, and hardness or Due to the lack of mechanical strength such as adhesion, it is easily scratched or peeled off inside the copying machine, making it difficult to form stable images over a long period of time. Limited number of copies. In order to improve these shortcomings,
When providing a surface layer, an adhesive layer, etc., there are problems such as an increase in residual potential and a complicated structure of the photoreceptor, which increases the occurrence of defects during the production of the electrophotographic photoreceptor.

In addition, electrophotographic photoreceptors using organic charge transport materials do not have sufficient transport properties, and have problems such as poor potential decay, especially in low-temperature environments, and are not suitable for high-speed copying operations. There was a problem.

In addition, electrophotographic photoreceptors using conventional charge transport materials do not have sufficient heat resistance or light resistance, and the charge transport material, which is a low-molecular-weight compound, crystallizes, or the charge transport material, which is a low-molecular-weight compound, becomes diagonal. It was necessary to restrict the conditions and environment in which the body was used or stored.

In addition, in electrophotographic photoreceptors that have a functionally separated structure and have a charge transport layer as a part of the photoconductive layer, the charge generation layer is generally a thin layer, so absorption of light near the absorption edge is reduced.
The amount of light passing through the charge generation layer increases, and as a result, especially in printers using infrared lasers, interference fringes are unavoidable due to multiple reflections with light reflected from the substrate.

The present invention has been made in view of the above-mentioned problems in the conventional technology.

Therefore, an object of the present invention is to provide an electrophotographic photoreceptor having a novel charge transport layer.

That is, the object of the present invention is to provide a highly durable electrophotographic photoreceptor having a charge transport layer with high adhesiveness, high mechanical strength and hardness, and few defects.

Another object of the present invention is to provide an electrophotographic photoreceptor that has high sensitivity, rich mediochromacy, high electroconductivity, low dark decay, and low residual potential after exposure.

Still another object of the present invention is to provide a high-quality electrophotographic photoreceptor that prevents the generation of interference fringes in a laser printer that uses coherent light such as an infrared semiconductor laser as a light source.

(Means and effects for solving the problem) The present inventors,
As a result of extensive research into charge transport materials that achieve the above objectives, we found that materials in which metal powder or conductive metal oxide powder is dispersed in organic polymer compounds efficiently transport photocarriers generated in the charge generation layer. They discovered that the charge transport material is well transported to the substrate side and has an excellent charge transport function.
It was discovered that the photoreceptor is chemically, mechanically, and optically superior to conventional photoreceptors using charge transport materials, and the present invention was completed.

Conventionally, conductive fine powder dispersed in an organic polymer compound has been used as a surface protective layer, but such a surface protective film is provided on the outermost surface of a photoreceptor and absorbs the charges on the surface in the dark. It is necessary to reach the surface of the layer, reduce charge accumulation in the protective layer, and reduce the amount of residual charge on the photoreceptor.
Such hWh3i cannot reduce potential attenuation in the dark and maintain sufficient charge as a photoreceptor like a charge transport layer. Further, in the case of a surface protective layer, its film thickness is determined in relation to its resistance; for example, if the resistance of the a-retaining layer is high, its film thickness must be made thin.

The electrophotographic photoreceptor of the present invention has at least a support, a charge transport layer, and a charge generation layer laminated in sequence, and the charge transport layer is made of an organic polymer compound in which metal powder or conductive metal oxide powder is dispersed. It is characterized by becoming. It is surprising that what has conventionally been used as a low resistance surface protective layer functions as a charge transport layer.

In the electrophotographic photoreceptor of the present invention, the metal powder dispersed in the organic polymer compound of the charge transport layer is selected from elements of group Ⅰa, group ffb, elements of group 1 [Ia and transition elements of the periodic table]. The conductive metal oxide powder is made of a selected element, or an alloy or mixture of two or more of these elements, or an oxide of an element selected from tin, zinc, antimony, titanium, and indium. Composite oxides of two or more elements or mixtures of two or more metal oxides are preferably used. These conductive fine powders are bipolar, allowing both positive and negative charges to flow, and a charge transport layer using them is bipolar.

The present invention will be explained in detail below.

FIG. 1 shows an example of the basic layer structure of the electrophotographic photoreceptor of the present invention, in which a charge transport layer 2 and a charge generation layer 3 are laminated on a support l. In FIG. 2, an intermediate layer 4 is provided on the support, and a protective layer 5 is provided on the surface.

In the present invention, the support may be either a conductive support or an insulating support.

Examples of the conductive support include metals such as aluminum, stainless steel, nickel, and chromium, and alloys thereof; examples of the insulating support include polymer films or sheets such as polyester, polyethylene, polycarbonate, polystyrene, polyamide, and polyimide; Examples include glass and ceramic. When using an insulating support, at least the surface that contacts other layers needs to be subjected to conductive treatment. In addition to the above-mentioned metals, the conductive treatment can be performed using gold, silver, copper, etc., by vapor deposition, sputtering, or ion blating.

In the electrophotographic photoreceptor of the present invention, electromagnetic waves may be irradiated from the support side or from the side opposite to the support. When performing from the support side, the metal layer formed by the conductive treatment may have a thickness that allows at least ++<t J1=l to pass through the electromagnetic waves. Moreover, a transparent conductive film such as ITO can also be used.

In the electrophotographic photoreceptor of the present invention, a charge generation layer and a charge transport layer are formed on the support.

When a charge generation layer and a charge transport layer are sequentially laminated on a substrate, it is necessary to further provide an insulating layer on the surface of the charge transport layer in order to effectively retain charges in the dark. However, in this case, since the charge transport layer is provided on the charge generation layer, the charge transport layer is exposed to electromagnetic waves (
It must be sufficiently transparent to allow sufficient light (light) to pass through and reach the charge generation layer below, and consideration must be given to the dispersion material used in the charge transport layer, film thickness, etc. In the present invention, since the charge generation layer is on top, there is no need to particularly consider transparency, which is advantageous in terms of material selection, film thickness, etc.

In the present invention, an intermediate layer may be provided between the support and the charge generation layer or the charge transport layer for the purpose of blocking charge injection and improving adhesion.

The intermediate layer can be formed by applying a solution of an organic polymer compound such as polyamide, polyimide, or polyester, or an alkoxy compound such as silicon, titanium, or zirconium, and drying the solution. Also, BRAZ 7CVD method L Yoru S
i N *, S t Ct, S r O by film, S joy % by PVD method such as ion blating
A 10. ,ZnO,,Z ro.

In addition to being able to use a film or the like, if the substrate is made of AI, it may be formed by anodizing to form an aluminum oxide layer.

As mentioned above, the charge transport layer is made of an organic polymer compound,
It is made by dispersing metal powder or conductive metal oxide powder.

As the metal powder, an element selected from elements of Group Ua, Group IIb, Group Ma, and transition metals of the periodic table is used. Be5Mg5C as the Group Ia element
Examples of group IIb elements include ZnSCd, examples of group IIa elements include A1, Ga, and In5Tl, and examples of transition elements include main transition elements. From Sc to Cu5Y to Ag11
Examples include each element from II'' to U, and each element from La to Lu, which is an element of 4 fJ', and from AC to L''.

Among these, A1, Zns In and main transition elements can be preferably used.

Further, as the conductive metal oxide powder, an oxide of a metal selected from tin, zinc, antimony, titanium, and indium is used. The metal oxide may be in the form of a composite oxide, or may be a mixture of two or more oxides.

The particle size of these metal powders or metal oxide powders needs to be smaller than the thickness of the charge transport layer, and is particularly preferably 1/10 or less of the thickness of the charge transport layer. is used in a range of 50 to 5, preferably 0.01 to 1.

When the particle size is smaller than 50 particles, the charge transport function is degraded, and when it is 5a+ or more, the surface properties of the film are degraded, causing poor cleaning and a decrease in resolution.

Examples of organic polymer compounds include polyvinylcarbazole,
Acrylic resin, polycarbonate resin, polyester resin, vinyl chloride resin, fluororesin, polyurethane resin,
Examples include epoxy resins, unsaturated polyester resins, polyamide resins, and polyimide resins. Among these, curable resins are preferred in terms of mechanical strength, adhesiveness, and moisture resistance.

In order to form the charge transport layer, the metal powder or metal oxide powder is dispersed in an organic solvent solution of the organic polymer compound or in a liquid polymer compound, and the resulting dispersion is applied and dried. Bye.

The ratio of the metal powder or metal oxide powder to the organic polymer compound is arbitrarily determined depending on the particle size and resistivity of the powder, the strength of the film, and the film thickness, but is usually 2/98 to 40/2 in terms of weight ratio.
A range of 80 is preferred. If the proportion of metal or metal oxide powder is lower than 2% by weight, the charge transport function will be insufficient and a high residual potential will be exhibited, and if it is higher than 40% by weight, the charging property will decrease and the photoconductor It is not possible to perform the functions of C.

The thickness of the charge transport layer is set in the range of 3 to 071+11, preferably 5 to 50.

In the present invention, the charge transport layer is capable of retaining charges in the dark and is capable of transmitting electromagnetic waves to j! When charges are generated in the charge generation layer due to α radiation, the charges can be quickly injected and transferred to the surface of the substrate or photoreceptor. In the present invention, since metal powder or conductive metal oxide powder is dispersed in the charge transport layer, it is thought that these powders form a predetermined electric path that becomes apparent only in the light. Horizontal charge movement occurs at the interface between the charge transport layer and the charge generation layer, and no charge remains at the interface between the electric circuits.

In addition, in the present invention, the charge transport layer can transport both positive and negative charges, so the photoreceptor can be transferred to a plus-i! It can be used charged or negatively charged.

Furthermore, since the chargeability of a functionally separated photoreceptor is determined by the thick charge transport layer, the chargeability of the charge transport layer in the present invention must be in the range of about 15V/a-100V/-. be. Furthermore, the ratio of the surface potential of the photoreceptor obtained based on the charge transport layer used in the present invention in the dark and in the case of light irradiation is at least 2, which is a value that is sufficiently applicable to electrophotographic processes.

On the charge transport layer formed by dispersing metal or conductive metal oxide fine powder in the polymer matrix of the present invention,
In order to effectively retain charge in the dark, a film that exhibits high resistance at least in the dark is required, and it is thought that the charge generation layer fulfills this function. However, in order to further enhance the charge retention ability, an insulating layer may be provided on the surface of the support, if necessary.

The charge generation layer is made of inorganic materials such as amorphous silicon, selenium, selenium arsenide, and selenium tellurium by CVD.

A material formed using a method such as vapor deposition or sputtering can be used. In addition, dyes and pigments such as phthalocyanine, Cu phthalocyanine, AI phthalocyanine, ■ phthalocyanine, squaric acid derivatives, merocyanine, bisazo dyes, etc., are vapor-deposited or dispersed in a binder resin, and then formed into a thin film by dip coating, spray coating, etc. can be used.

In the present invention, Se, 5e-
When a selenium-based charge generation layer such as To or an a-8I charge generation layer is used, it is advantageous in terms of abrasion resistance and abrasion resistance compared to the case where an organic charge generation material is used. In particular, the a-8I charge generation layer has high hardness and is extremely advantageous as the outermost layer. Further, from the above point of view, the a-8I film can be effectively used as a surface layer.

Among these, when hydrogenated amorphous silicon, hydrogenated amorphous silicon added with germanium, and hydrogenated amorphous germanium are used, excellent mechanical and electrical properties are exhibited. In particular, silicon or germanium is the main component, and l~40
It is preferable to use hydrogen containing 5 to 20 atomic % of hydrogen.

Since the charge transport layer of the present invention is bipolar and can transport both positive and negative charges, the a-3l charge generation layer is optimal from the viewpoint of charge polarity of the photoreceptor. This is because the a-9i film can easily form n-type, i-type, and p-type films by adding group V elements and group II elements of the periodic table of elements to the film, making it suitable for positively charged photoreceptors. If desired,
A pJua-Sl charge generation layer doped with group elements may be used. If a negatively charged photoreceptor is desired, a group V element may be added or an n-type a-8l charge generation layer may be formed as is. If a bipolar photoreceptor is desired, the charging polarity of the photoreceptor can be easily controlled by adding a small amount of group (I) element to form an i-type A-3L charge generation layer. be.

Hereinafter, a case where hydrogenated amorphous silicon is used as a charge generation layer will be explained as an example.

The charge generation layer containing amorphous silicon as a main component can be formed by a known method. For example, it can be formed by glow discharge decomposition, sputtering method, ion blating method, vacuum evaporation method, etc. These film forming methods are appropriately selected depending on the purpose, but plasma CV
It is preferable to decompose silane or silane-based gas by glow discharge using method D. According to this method, 1 to 4
A film containing 0 atomic % of hydrogen, which has relatively high resistance and high photosensitivity, is formed, and has suitable characteristics as a charge generation layer.

The following will explain the plasma CVD method as an example.

Examples of the raw material gas for creating a charge generation layer containing silicon as a main component include silanes such as silane and disilane. Further, when forming the charge generation layer, it is also possible to use a carrier gas such as hydrogen, helium, argon, neon, etc., if necessary. These raw material gases contain diborane (B2H6), phosphine (PH3
) It is also possible to add impurities such as boron or phosphorus into the film by introducing a dopant gas such as a gas. Further, for the purpose of increasing photosensitivity, halogen atoms, carbon atoms, oxygen atoms, nitrogen atoms, etc. may be contained.

Furthermore, it is also possible to add elements such as germanium and tin for the purpose of increasing the sensitivity in the long wavelength region. The thickness of the charge generation layer is 0. 1~30 liters, preferably 0.2~
The range is set to 10m+.

The electrophotographic photoreceptor of the present invention may be provided with a surface protective layer in order to prevent surface deterioration due to corona ions. As a material for forming the surface protective layer, plasma C
Examples include silicon oxide, silicon carbide, silicon nitride, amorphous carbon produced by the VD method, alumina oxide produced by the ion-blating method, and transparent organic polymer films in which organic low-molecular compounds and conductive fine powder are dispersed.

(Example) Next, the present invention will be explained by examples.

Example 1 70 parts by weight of polyurethane resin (manufactured by Kansai Paint Co., Ltd., Rethane 400.0) was placed on a cylindrical aluminum vibe.
Add 30 parts by weight of copper powder with an average particle size of about 0.5 or less and 15 parts by weight of rethane thinner (manufactured by Kansai Paint Co., Ltd.), mix and disperse using a ball mill for 20 hours, and add a rethane hardener (manufactured by Kansai Paint Co., Ltd.). A solution containing 9 parts by weight was spray coated and dried at 120° C. for 2 hours to form a charge transport layer with a thickness of 15 m.

Thereon, a charge generation layer and a surface protection layer having the following composition were successively laminated to obtain an electrophotographic photoreceptor.

Charge generation layer (film thickness 1 cape) Squaric acid derivative 30 parts by weight 0 (I) Polyester resin 70 parts by weight (manufactured by Toyobo ■, Vylon-200) Low resistance surface protective layer (film thickness 2 capes) Tin oxide powder 45 parts by weight Part: Polyurethane resin: 48 parts by weight (Nyrethane clear manufactured by Kansai Paint Co., Ltd.) Curing agent: 7 parts by weight When the electrophotographic properties of the obtained electrophotographic photoreceptor were investigated, +
With an 8KV corotron; jl [then, pull) 1 point 5
00V)! I did it. The residual potential after exposure to 550 nm light was IOV.

Example 2 An electrophotographic photoreceptor was produced in the same manner as in Example 1 except that the charge generation layer was formed using crystalline selenium powder.

The charge generation layer was formed by dip coating a dispersion having the following composition.

70 parts by weight of crystalline selenium with a particle size of 0.05 to 0.5 mm Polyvinyl butyral 30 parts by weight (manufactured by Block Chemical ■, nM-1) 100 parts by weight Butyl alcohol The electrophotographic properties of the obtained electrophotographic photoreceptor were determined by δIl + Then, when I did 4i'r f[E with +BKV corotron,
A charging potential of 460V was maintained. The residual potential after exposure to 500 r++++ light was IOV. Further, the photosensitivity was 6 ergs/C- at half exposure.

Example 3 On a cylindrical aluminum pipe, 70 parts by weight of polyurethane resin (manufactured by Kansai Paint Co., Ltd., Rethane 4000), 20 parts by weight of Ni powder with an average particle size of about 0.3 centimeters or less, and rethane thinner (manufactured by Kansai Paint Co., Ltd.) 15 parts by weight were added, mixed and dispersed for 20 hours using a ball mill, and a solution containing 9 parts by weight of a urethane curing agent (manufactured by Kansai Paint Co., Ltd.) was spray applied, dried at 150°C for 24 hours, and a 15 μs thick film was formed. A charge transport layer was formed.

The aluminum pipe on which only the charge transport layer was formed was placed in a vacuum chamber of a capacitively coupled plasma CVD apparatus.

The substrate temperature was maintained at 200°C, 100% silane (SiH4) gas was introduced into the reaction chamber at a rate of 100 cc/min, and LO was diluted with hydrogen.
OppI11 diborane (B, 2H6) gas at 2cc per minute
After the pressure inside the reaction tank was maintained at 0.5 Torr, a high frequency power of 13.85 MIIz was applied to generate a glow discharge, and the power was maintained at too much. In this way, an ltm charge generation layer made of so-called i-type amorphous silicon and having a high dark resistance containing hydrogen and a very small amount of boron was formed. Continuing to evacuate to high vacuum, S i H430
secm, NH330secI11 was introduced into the reactor, and discharge was performed at 50 W to form a 0.1 inch SIN film, thereby producing an electrophotographic photoreceptor having a photosensitive layer with a thickness of about 16 ET+.

When the electrophotographic characteristics of the obtained electrophotographic photoreceptor were determined by AP1, it was found that when charged with a +6 KV corotron, a charging potential of 450 V was maintained. The residual potential after exposure to 550 r+m light was lOv.

Using this electrophotographic photoreceptor, 10,000 copies were made by repeating the steps of positive charging, image exposure, development and transfer, and cleaning according to the usual electrophotographic method, and good images were obtained. Further, when this photoreceptor was charged with a voltage of 41F using a corotron of -6 KV, the voltage was maintained at -470V. 5
When exposed to 50 nm light, the residual potential was -10 V, confirming that the photoreceptor was bipolar.

Example 4 On a cylindrical aluminum pipe, 70 parts by weight of polyurethane resin (manufactured by Kansai Paint Co., Ltd., Rethane 4000) contained tin oxide and antimony oxide with an average particle size of about 0.3- or less in the same particle, 15 parts by weight of an oxide powder with an antimony oxide content of 15% by weight in the particles, and 15 parts by weight of rethane thinner (manufactured by Kansai Paint Co., Ltd.) were mixed and dispersed for 20 hours using a ball mill. Spray a solution containing 9 parts by weight of
It was dried at 150° C. for 24 hours to form a charge transport layer with a thickness of 15 IJn.

On top of this, an FFS charge generation layer and a surface protection layer having the following composition were successively laminated to obtain an electrophotographic photoreceptor.

Charge generation layer (thickness IEI) Squaric acid derivative 30 parts by weight (Structural formula (I) above) Polyester resin 70 parts by weight (manufactured by Toyobo, Vylon-200) Low resistance surface protective layer (thickness 2-) Oxidation Tin powder: 45 parts by weight Polyurethane resin: 48 parts by weight (Nyrethane Clear manufactured by Kansai Paint ■) Curing agent: 7 parts by weight When the electrophotographic properties of the obtained electrophotographic photoreceptor were examined, it was +6K.
When charged with a V corotron, a charged potential of 500V was maintained. Residual potential after exposure to 550nm light is 20V
Met.

Example 5 An electrophotographic photoreceptor was produced in the same manner as in Example 4 except that the charge generation layer was formed using crystalline selenium powder.

The charge generation layer was formed by dip coating a dispersion having the following composition.

Particle size: 0.05 to 0.5 1M Crystalline selenium 70 parts by weight Polyvinyl butyral 30 parts by weight (manufactured by Block Chemical Co., Ltd., ■-1) Butyl alcohol 1oOfflJ [The electrophotographic properties of the obtained electrophotographic photoreceptor were measured] ,
When charged with a +6KV corotron, the charging potential is 450V.
was held. The residual potential after exposure to 500 nIm of light was lOv. Further, the photosensitivity was 4 ergs/cd at half exposure.

Example 6 On a cylindrical aluminum pipe, 70 parts by weight of polyurethane resin (Rethane 4000, manufactured by Kansai Paint Co., Ltd.), 20 parts by weight of tin oxide powder with an average particle size of about 0.3 or less, and rethane thinner (manufactured by Kansai Paint Co., Ltd.) were placed on a cylindrical aluminum pipe. ), mixed and dispersed for 20 hours using a ball mill, sprayed with a solution containing 9 parts by weight of a urethane curing agent (manufactured by Kansai Paint Co., Ltd.), dried at 150°C for 24 hours, and then A 15-charge transport layer was formed.

On top of this, a charge generation layer and a surface protective layer made of amorphous silicon similar to those in Example 3 were sequentially laminated by plasma CVD in the same manner as in Example 3, thereby producing an electrophotographic photoreceptor with a photosensitive layer thickness of 1 Bm+. was created.

When the electrophotographic properties of the obtained electrophotographic photoreceptor were measured, it was found that when charged with a +6KV corotron, the charging potential was 3.
50V was maintained. The residual potential after exposure to 550 nm light was 15V.

Using this electrophotographic photoreceptor, 10,000 copies were made by repeating the steps of positive charging, image exposure, development and transfer, and cleaning according to the usual electrophotographic method, and good images were obtained.

Example 7 On a charge transport layer made of pith in the same manner as in Example 6, silane gas and hydrogen-diluted germane gas were added to the germane content ratio of 20% instead of the silane gas in Example 3 using the plasma CVD method. An amorphous silicon germanium layer was formed by operating under the same conditions except that a mixed gas mixed as described above was used. Moreover, Example 3
A surface layer was formed in the same manner as above to produce an electrophotographic photoreceptor.

When this electrophotographic photoreceptor was attached to a printer (XP-9, manufactured by Fuji Xerox ■) using a 7800-inch semiconductor laser and a copying operation was performed, a clear image without moiré patterns was obtained.

As a result of measuring the reflection spectrum of this electrophotographic photoreceptor,
In the reflection spectrum, no difference in intensity due to interference was observed, and it was confirmed that j7 functioned as an interference prevention layer for any coherent light in the visible range.

(Effects of the Invention) As described above, the electrophotographic photoreceptor of the present invention has a charge transport layer made of an organic polymer compound in which metal powder or conductive metal oxide powder is dispersed. Compared to the case where a layered material is used, the charge mobility is greater and the heat resistance is excellent.

It also has the advantage of good adhesion and fewer defects. However, the electrophotographic photoreceptor of the present invention exhibits the following effects: high durability, high sensitivity, rich in mediochromatic properties, high chargeability, low dark decay, and low residual potential after exposure.

Further, the electrophotographic photoreceptor of the present invention can be used in a device that uses coherent light such as an infrared semiconductor laser as a light source, and can obtain high-quality images that prevent interference fringes from occurring in a laser printer.

[Brief explanation of drawings]

FIG. 1 is a schematic sectional view of an embodiment of the electrophotographic photoreceptor of the present invention, and FIG. 2 is a schematic sectional view of another embodiment of the electrophotographic photoreceptor of the invention. 1... Support, 2... Charge transport layer, 3... Charge generation layer, 4... Intermediate layer, 5... Surface protective layer.

Claims (6)

[Claims] (1) At least a support, a charge transport layer, and a charge generation layer are sequentially laminated, and the charge transport layer is made of an organic polymer compound in which metal powder or conductive metal oxide powder is dispersed. Electrophotographic photoreceptor. (2) The metal powder is characterized by being made of an element selected from Group IIa elements, Group IIb elements, Group IIIa elements and transition elements of the periodic table, or an alloy or mixture of two or more of these elements. An electrophotographic photoreceptor according to claim 1. (3) The metal oxide powder consists of an oxide of an element selected from tin, zinc, antimony, titanium, and indium, a composite oxide of two or more of these elements, or a mixture of two or more metal oxides. An electrophotographic photoreceptor according to claim 1, characterized in that: (4) The electrophotographic photoreceptor according to any one of claims 1 to 3, wherein the charge generation layer contains chalcogenide as a main component. (5) The electrophotographic photoreceptor according to any one of claims 1 to 3, wherein the charge generation layer is mainly made of amorphous silicon and/or amorphous germanium. (6) The electrophotographic photoreceptor according to any one of claims 1 to 3, wherein the charge generation layer mainly consists of an organic dye or an organic pigment.