JPH0339966A - Electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To enhance mobility of electric charge, as well as resistance, adhesion, mechanical strength, and hardness to reduce defects by forming a charge transfer layer made of an inorganic 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 inorg. polymer compd. containing in a dispersed state the powder of the metal, preferably, selected from elements of groups IIa, IIb, and IIIa of the 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, and charge transfer function, adhesion, mechanical strength, and hardness to be enhanced.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an electrophotographic photoreceptor, particularly an electrophotographic photoreceptor having a functionally separated photosensitive layer.

(Prior Art) Conventionally, the photosensitive layer of an electrophotographic photoreceptor has been separated into a charge generation layer that generates charge carriers upon irradiation with light and a charge transport layer that efficiently moves these charge carriers, so-called functional separation. 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 and triphenylamines dispersed or dissolved 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 and Or, because it lacks mechanical strength such as adhesion, it is easily scratched or peeled off in the copying machine, making it difficult to form stable images over a long period of time, and its lifespan is limited to several thousand to tens of thousands of copies. The number of copies is limited. 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 electrophotographic photoreceptors. Ta.

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 materials, which are low molecular weight compounds, may crystallize or decompose.
It has been necessary to limit the conditions and environment in which electrophotographic photoreceptors are 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, is rich in mediochromaticity, has high chargeability, has little dark decay, and has little 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) As a result of intensive research into charge transport materials that achieve the above objectives, the present inventors mainly incorporated metal powders or conductive metal oxide powders into inorganic polymers. The dispersed material efficiently transports the photocarriers generated in the charge generation layer to the substrate side, and has an excellent charge transport function.Functionally separated photoreceptors using this charge transport material have physical advantages. The present inventors have discovered that photoreceptors using conventional charge transport materials are chemically, mechanically, and optically superior to photoreceptors using conventional charge transport materials, and have completed the present invention.

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 residual potential of the photoreceptor. Otherwise, it cannot maintain sufficient charge as a photoreceptor. Further, in the case of a surface protective layer, the film thickness is determined in relation to the resistance; for example, if the resistance of the protective layer is high, the 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 inorganic 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 inorganic polymer compound of the charge transport layer is
The conductive metal oxide powder is made of an element selected from group elements, group IIb elements, group IIIa elements, and transition elements, or a compound or mixture of two or more of these elements. Oxides of elements selected from antimony, titanium, and indium, composite oxides of two or more of these elements, or mixtures of these 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 surface 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, it is necessary that at least the surface in contact with other layers be subjected to conductive treatment.In addition to the above metals, the conductive treatment may include gold, silver, copper, etc. This can be done by vapor deposition, sputtering, or ion blating methods.

The electrophotographic photoreceptor of the present invention is capable of handling electromagnetic waves! ! <t all
This may be performed from the support side or from the side opposite to the support. When performing from the support side, the metal layer subjected to the conductivity treatment may have a thickness that allows at least the irradiated electromagnetic waves to pass through. 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 must be sufficiently transparent to allow electromagnetic waves (light) used for exposure to sufficiently pass through and reach the charge generation layer below. However, the dispersion material used for the charge transport layer, film thickness, etc. must be considered. 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 inhibiting charge injection and improving adhesion.

The intermediate layer can be formed by melting and coating an organic polymer compound such as polyamide, polyimide, polyester, or an alkoxy compound such as silicon, titanium, zirconium, and the like, and drying it. We also provide stN, SIC, SiOx films by plasma CVD, and SiOx, AlOx, Zn0x by PVD such as ion blating.
, ZrOx film, etc. can be used, and the substrate can be
In this case, an aluminum oxide layer may be formed by anodizing.

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

As the metal powder, an element selected from Group Ua elements, Group IIb elements, Group 1IIa elements, and transition metals of the periodic table is used. Group na elements include Be, H
gs Ca, Sr, Ba5Ra are mentioned, and IIb
Examples of group elements include ZnSCd, and examples of group IIIa elements include Ga, In, and TI.
As transition elements, from Sc, which is the main transition element, to Cu
Examples include each element from Y to Ag111f' to ^U, and each element from La to L u s^C to L', which are internal transition elements.

Among these, Z, Zn, In and the main transition elements can be preferably used.

In addition, examples of conductive metal oxide powder include tin, zinc,
Oxides of metals selected from antimony, titanium and indium are 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 conductive metal oxide powders is
It needs to be smaller than the thickness of the charge transport layer, particularly preferably 1/10 or less of the thickness of the charge transport layer, specifically 50 to 5 tl! a.

Preferably, those in the range of 0.01- to I- are used. When the particle size is smaller than 50 particles, the charge transport function is degraded, and when it is larger than 5a, the surface properties of the film are degraded, causing poor cleaning and a decrease in resolution.

As the inorganic polymer compound, an inorganic polymer compound formed from a silicone resin or an organic gold scrap compound can be used.

When forming the charge transport layer, if the inorganic polymer compound is, for example, a liquid silicone resin, the above-mentioned metal powder or metal oxide powder may be dispersed therein, and a dispersion liquid may be applied and dried. .

Moreover, when forming by a sol-gel method, it can be formed as follows.

SL (OCH3) 4, S * (OC2H5)
4, Si (OC3H7) 4, Si (OC4
Hg)4, AI (OCH3)3, AI (OC2
H5) 3, A I (OC4H9) 3, T i
(OC3H7) 4, Zr (OC3H7) 4, Ti
(OC3H7) 4, Y (OC3H7) 3, Y(O
C4H9)3, Fe (OC2H5)3, Fe (OC
3H7)3, Fe (OC4H9)3, Nb (OCH
3) 5, Nb (OC2H5) 5, Nb (OC3H7
)5, Ta (OC3H7)5, Ta(OC4H9)4
, Ti (OC3H7)4, V (OC2H5)3,
Alkoxide compounds such as V(OC4H9)3, organic metals such as iron, tris (acetylacetonate), cobalt/bis(acetylacetonate), nickel/bis(acetylacetonate), copper/bis(acetylacetonate), etc. The complex is dissolved in alcohol and hydrolyzed with stirring. The above metal powder or metal oxide powder is dispersed in a sol liquid purified by reaction, the resulting dispersion is applied onto a substrate by a spray method or a dipping method, and after removing the solvent, it is heated at 50 to 300°C for 1 to 30 minutes. By heating and drying for 24 hours, a charge transport layer mainly composed of an inorganic polymer compound can be obtained.

The ratio of the metal or metal oxide powder to the inorganic polymer compound in the charge transport layer can be arbitrarily determined depending on the particle size and resistivity of the powder, the strength of the film, the film thickness, etc.
Usually, the weight ratio is preferably in the range of 2/98 to 40/BO.

Note that 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 unable to perform its functions.

The thickness of the charge transport layer is 3 to 100 us, preferably 5 to 100 us.
It is set to a range of 50 subdivisions.

In the present invention, the charge transport layer is capable of retaining charges in the dark, and when charges are generated in the charge generation layer due to irradiation with electromagnetic waves, the charges are quickly injected and the charge is transferred to the substrate or photosensitive layer. It can transfer charges to the surface of the body. In the present invention, since metal powder or conductive metal oxide powder is dispersed in the charge transport layer, it is thought that a predetermined electric path is formed by these powders, which only becomes apparent. Horizontal charge movement occurs at the interface between the transport layer and the charge generation layer, and no charge remains at the interface between the electrical circuits.

Further, in the present invention, since the charge transport layer can transport both positive and negative charges, the photoreceptor can be used with a positive charge or a negative charge.

Furthermore, one of the features of the functionally separated photoreceptor! i) Since the chargeability is determined by the thick charge transport layer, the chargeability of the charge transport layer in the present invention is about t5V/body ~ 100V
It is necessary to be in the range of /-. 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, Al phthalocyanine, ■ phthalocyanine, squaric acid derivatives, merocyanine, and bisazo dyes are vapor-deposited or dispersed in a binder resin, and then formed into thin films by methods such as dip coating and soubreco coating. can be used.

In the present invention, Se is used to form the charge generation layer as an upper layer.

When a selenium-based charge generation layer such as 5o-To or an a-8L charge generation layer is used, it is advantageous in terms of abrasion resistance and abrasion resistance compared to when an organic charge generation H material is used. In particular, the a-S1 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 1 to 40
It is preferable that the hydrogen content be 5 to 2 atomic %, especially 5 to 2 atomic %.

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 allows n-type, iTM, and p-type films to be easily formed by adding group V elements and group II elements of the periodic table of elements to the film, making it possible to form positively charged photoreceptors. If desired, a p-type A-81 charge generation layer may be added with a group I element, and if a negatively charged photoreceptor is desired, a group V element may be added or the n-type charge generation layer may be added as is. A type A-8I charge generation layer may be used, and if a bipolar photoreceptor is desired, a trace amount of Group Ⅰ element can be added to form an I type A-8I charge generation layer. This is because the charging polarity of the photoreceptor can be controlled.

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 selected as appropriate depending on [1], but plasma C
It is preferable to decompose silane or silane-based gas by glow discharge using the VD method. According to this method, l~
Relatively high resistance containing 40 atomic % hydrogen, and
A film with high photosensitivity is formed, and characteristics suitable for a charge generation layer can be obtained.

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.In addition, when forming the charge generation layer, hydrogen, It is also possible to use carrier gases such as helium, argon, neon, etc. 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 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 to increase the sensitivity in the long wavelength range. The thickness of the charge generation layer is 0.1 to 30 μM, preferably 0.1 to 30 μM.
It is set in the range of 2 to IOμs.

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 On an aluminum flat plate, 80 parts by weight of Ceramica 1100 (manufactured by Doiban Kenkyujo Co., Ltd.) contained tin oxide and antimony oxide in the same particles, and antimony oxide in the particles was 10% by weight. 20 parts by weight of powder was added, dispersed for 100 hours using a ball mill, and 20 parts by weight of a curing agent was added, and the resulting coating solution was applied by dip coating method.
It was dried at 0° C. for 5 hours to form a charge transport layer with a thickness of 15 ml. When this film was analyzed using XI)S, no substances other than silicon oxide, tin oxide, and antimony oxide were detected.

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

Charge generation layer (film thickness 1 μs) Squaric acid derivative 30 parts by weight (1) Polyester resin 70 parts by weight (manufactured by Toyobo, Vylon-200) K-resistant surface protective layer (film thickness 27Z11) Tin oxide powder 45 fff parts Polyurethane Resin 48-layer foot (manufactured by Kansai Paint ■).

(Lethane clear) Hardening agent (Lethane hardening agent) 7 parts by weight IIL
7. The electrophotographic properties of the electrophotographic photoreceptor obtained by ! When I turned on the +8KV corotron (;shiden),...
1) Maintain 570V of electrical power! j I did. The residual potential after exposure to 550 ni light was 1.5V.

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 0.5a After setting,
When charged with a +6Kv corotron, the electric potential is 470■
was held. The residual potential after exposure to 500 nn+ light was 20V. Further, the photosensitivity was 4 ergs/ci at half exposure.

Example 3 On a cylindrical aluminum pipe, 50 parts by weight of tetraethoxysilane, 30!1f of ethyl alcohol, 1 part, and 2 parts of water were placed on a cylindrical aluminum pipe.
Adding 10 parts by weight of tin oxide powder to a mixture consisting of parts by weight,
The coating solution obtained by dispersing in a ball mill for 100 hours was repeatedly coated using the dip coating method to a thickness of 10tI! A charge transport layer of R was formed.

A charge generation layer and a surface protective layer made of amorphous silicon were sequentially laminated thereon by a plasma method in the following manner to obtain an electrophotographic photoreceptor.

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, too% silane (SiH4) gas was introduced into the reaction chamber at a rate of 100 cc/min, and hydrogen dilution was performed at 11
After 2cc of 00pp diborane gas was introduced per minute and the pressure inside the reaction tank was maintained at 0.5 Torr, 1.3.85M
I turned on the IIz Shinshu Denno J to let the glow discharge sit and maintain the power 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.

Subsequently, evacuate to high vacuum and S i H430sec
, N H330sec+a was introduced into the reactor and discharged at 50W to form a film with a SIN of 0.1- and a thickness of about 2
An electrophotographic photoreceptor having a single photosensitive layer was prepared.

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 40
0v was maintained. The residual potential after exposure to 550 na+ light was 15V.

Further, when this photoreceptor was charged with a corotron of -[iKV, -430V was maintained. When exposed to 550 na+ light, the residual potential was -20 V, confirming that this photoreceptor was bipolar.

When this electrophotographic photoreceptor was used to copy 100,000 copies according to the usual electrophotographic method by repeating the steps of positive charging, image exposure, development and transfer, and cleaning, good images were obtained. .

Example 4 On an aluminum flat plate, 20 parts by weight of copper powder with a particle size of 0.1-0.5 was added to 60 parts by weight of Ceramigalo 00 (manufactured by Nippan Research Institute Co., Ltd.) and dispersed for 100 hours using a ball mill. Then, the coating solution obtained by adding 20 parts by weight of a curing agent,
Coated by dip coating method, dried at 150°C for 5 hours,
A charge transport layer having a thickness of i5- was formed.

On top of this, a charge generation layer and a surface protective layer were sequentially laminated as in Example 1 to obtain an electrophotographic photoreceptor.

When the electrophotographic properties of the obtained electrophotographic photoreceptor were investigated, it was found that when charged with a +6KV corotron, the charging potential was 450.
v was retained. The residual potential after exposure to 550 tn light was 20V.

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.

70 parts by weight of crystalline selenium with a particle size of 0.05 to 0.5- parts by weight Polyvinyl butyral 30 parts by weight (manufactured by Tsukiki Kagaku ■, 13M-1) 100 parts by weight of butyl alcohol The electrophotographic characteristics of the obtained electrophotographic photoreceptor were measured. However, +
When charged with a BKV corotron, a charged potential of 500 μ was maintained. The residual potential after exposure with 500ni light is l
It was Ov. Further, the photosensitivity was 4 ergs/C- at half exposure.

Example 6 A mixture of 50 parts by weight of tetraethoxysilane, 30 parts by weight of ethyl alcohol, and 2 parts by weight of water was placed on a cylindrical aluminum vibe, and 1 part of Ni powder with a particle size of 0.1 to 0.5 was added.
A coating solution obtained by adding 0 parts by weight and dispersing in a ball mill for 100 hours was repeatedly coated by a dip coating method to form a charge transport layer with a thickness of 10 cm.

A charge generation layer and a surface protective layer made of amorphous silicon were sequentially laminated thereon by plasma CVD in the following manner to obtain an electrophotographic photoreceptor.

The aluminum vibrator 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, and 100% silane (SiH4) gas was supplied into the reaction chamber at a rate of 100 cc/min.
After introducing 2 cc of 00pp diborane gas per minute and maintaining the pressure inside the reaction tank at 0.5 Torr, 13.85M1
A glow discharge was generated by applying high frequency power of 1z, and the power was maintained at 100W. In this way, an l- charge generation layer made of so-called i-type amorphous silicon was formed with a high dark resistance containing hydrogen and a very small amount of boron.

Subsequently, evacuate to high vacuum and S i H430sec
, N H330sec+11 was introduced into the reactor, and 50W
A discharge was performed to form a film with a SIN of 0.1-, and an electrophotographic photoreceptor having a photoreceptor layer with a thickness of about 8 μs was produced.

When the electrophotographic properties of the obtained electrophotographic photoreceptor were measured, it was found that when it was electrified with a +6 KV corotron, a charged potential of 400 V was maintained. The residual potential after 550 light exposures was 15V.

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

Example 7 On the charge transport layer created in the same manner as in Example 4, silane gas and hydrogen-diluted germane gas were added to the charge transport layer, in place of the silane gas in Example 6, using a plasma CVD method so that the germane content ratio was 20%. 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 6
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 780 nm semiconductor laser and a copying operation was performed, a clear image without moire patterns was obtained.

As a result of measuring the reflection spectrum of this electrophotographic photoreceptor,
The reflection spectrum showed no strength or weakness of the reflected light due to interference, confirming that it functions as an interference prevention layer for any coherent light in the visible range.

(Effects of the Invention) As described above, in the electrophotographic photoreceptor of the present invention, the charge transport layer is made of an inorganic polymer compound in which metal powder or conductive metal oxide powder is dispersed. Compared to the case where RRS material is used, the mobility of the RRS load is large and the heat resistance is excellent. It also has the advantage of high adhesiveness, high mechanical strength and hardness, and fewer defects. Therefore, the electrophotographic photoreceptor of the present invention exhibits the following effects: high durability, high sensitivity, rich bichromaticity, 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 are prevented from generating interference fringes in laser printers.

[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 n:
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 inorganic polymer compound in which metal powder or conductive metal oxide powder is dispersed. Electrophotographic photoreceptor. (2) The metal powder is 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 is an oxide of an element selected from tin, zinc, antimony, titanium, and indium, or 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 the electrophotographic photoreceptor comprises: (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.