JPS60247644A - Electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To enhance sensitivity, repetition characteristics, durability, etc., by using a hydrazone compd. specified in structure as an electrostatic charge transfer material. CONSTITUTION:The hydrazone compd. specified in structure is represented by the formula in which X is O, S, or optionally substd. imino; R1, R2 are each independently alkyl, aralkyl, aryl, or heterocyclic; R3, R4 are each independently H, alkyl, aralkyl, alkoxy, or halogen; R5 is alkyl, aralkyl aryl, or heterocyclic; R6, R7 are each independently H, halogen, alkyl, alkoxy, aryl, amino, or alkylamino; and n is 0 or 1. Since the hydrazone compd. itself has no film forming ability, a binder resin is used to form a photosensitive layer. Preferable binders are highly electrically insulating film-forming polymers and copolymers.

Description

[Detailed description of the invention] [Purpose of the invention] (Industrial application field) The present invention relates to an electrophotographic photoreceptor.

More specifically, the present invention provides an electrophotographic photoreceptor having excellent photosensitivity and durability by incorporating a novel hydrazone compound into a photoconductive layer formed on a conductive support.

(Prior Art) The electrophotographic method has already been published by Carlson in US Patent No. 2.297.
As disclosed in No. 691, this photographic method is a clever combination of electrostatic phenomena and photoconductive phenomena, in which one surface of a photoconductive photoreceptor is uniformly charged by corona discharge etc. in a dark place. This is an image forming method in which the optical image is converted into an electrostatic latent image using photoconductivity, and colored charged powder (toner) is attached to the image to convert it into a visible image.

These are the basic electrical and photoelectric properties required of photoreceptors in electrophotography.

The characteristics include being able to be charged to an appropriate potential in a dark place, being able to maintain this potential for an appropriate amount of time, and being able to quickly dissipate the charge by light irradiation.

In such photoreceptors, amorphous selenium,
Inorganic photoconductive materials such as cadmium sulfide and zinc oxide have been widely used. Although these inorganic materials satisfy the above conditions, they also have some drawbacks. For example, cadmium sulfide and zinc oxide are used as photoreceptors by dispersing them in a resin as a binder, but they require smoothness, flexibility, hardness, and tensile strength.

Since it has mechanical defects such as abrasion resistance, it cannot withstand repeated use as it is. Furthermore, when using cadmium sulfide, consideration must also be given to hygiene issues.

In addition, amorphous selenium must be manufactured by vapor deposition, which not only increases manufacturing costs but also has no flexibility and is difficult to process into a belt shape.
It has drawbacks such as the toxicity of selenium and its sensitivity to heat and mechanical shock, so care must be taken when handling it.

In recent years, in order to eliminate the drawbacks of these inorganic photoreceptors,
Research on organic photoreceptors is progressing, and organic photoreceptors.

Two kinds of organic photoreceptors have been proposed, and some are in practical use because they have many advantages such as ease of coating, ease of manufacture, light weight, flexibility, and variable spectral sensitivity.

For example, poly-N-vinylcarbazole and 2°4.7-
) Dinitrofluoren-9-one and a color photoreceptor (U.S. Pat. No. 3,484,237), poly-N-vinylcarbazole sensitized with biryllium base dye (Japanese Patent Publication No. 4B-25658), dye and JP-A-47-10735: Photoreceptor whose main component is a eutectic complex consisting of a resin
Publication No.) etc.

Additionally, an electrophotographic photoreceptor has been proposed that combines a substance that generates electric charge when exposed to light (called a charge-generating substance) and a substance that can transport the generated electric charge (called a charge-transporting substance). . For example, U.S. Patent No. 3.791.
The specification of No. 826 also describes a photoreceptor in which a charge transport layer is provided on a charge generation layer.

U.S. Pat. No. 3,764,315 describes a photoreceptor having a photosensitive layer having a charge generating material dispersed in a charge transporting material. By assigning the functions of this type of charge generation and charge transport to separate substances, that is, by combining a charge generation material and a charge transport material, the characteristics can be improved and a useful photoreceptor can be provided. be done.

And so far, in this kind of photoreceptor.

Many useful charge generating materials are known. on the other hand.

Various materials have been proposed as charge transport materials, but
The current situation is that it is difficult to say that the situation is necessarily satisfactory.

The basic characteristics of an excellent charge transport material are that when it is charged, it can hold a sufficient potential, and that it can sufficiently transmit light of an effective wavelength that allows the charge to be generated from the charge-generating material. Furthermore, it has the ability to quickly transport the charges generated by the charge generating substance. Practical requirements include the ability to form a uniform film alone or dissolved in a binder, temperature, humidity, and ozone and NO generated during corona discharge.
It is necessary that the electrostatic properties do not deteriorate or change under harsh environmental conditions such as those caused by. So far,
Classified by chemical structural formula, this type of charge transport material includes polyphenyl compounds such as triphenyl, U.S. Pat. No. 3.717.462 and U.S. Pat. No. 4.150.987.
No., hydrazone compounds described in JP-A No. 55-52064, diarylalkane compounds described in U.S. Pat. No. 3.820.989, U.S. Pat. No. 3.189.477. 2 listed in
, 5-bis(P-diethylaminophenyl)-1,3,
4-Oxadiazole, U.S. Patent No. 3.837.851
Pyrazoline compounds and the like described in the specification are relatively excellent charge transport materials that have been proposed in recent years. However, the current situation is that these charge transport materials do not satisfy all of the above conditions.

(Problems to be Solved by the Invention) The present invention provides an electrophotographic photoreceptor having excellent sensitivity, repeatability, durability, and the like.

[Structure of the invention]

(Means for Solving the Problem) As a result of intensive research, the present inventors discovered that a hydrazone compound with a specific structure is a truly useful charge transport material for electrophotographic photoreceptors, and further discovered that The present invention was completed by discovering that an electrophotographic photoreceptor using a charge transporting material has excellent properties.

That is, the present invention provides an electrophotographic photoreceptor having excellent properties using a hydrazone derivative having a novel structure.

An object of the present invention is to provide an electrophotographic photoreceptor with high sensitivity and low residual potential by containing a novel charge transporting substance. Another object of the invention is charging exposure,
When used as a photoreceptor for repetitive transfer type electrophotography where development and transfer steps are repeated, there is little fatigue deterioration due to repeated use.

Furthermore, it is an object of the present invention to provide an electrophotographic photoreceptor with excellent durability and environmental friendliness that maintains stable characteristics under various harsh environments such as high temperatures rather than low temperatures and high humidity rather than low humidity.

This object of the present invention is achieved by containing at least one hydrazone compound represented by the following general formula (1) as a charge transport material.

General formula (I) 7 (wherein, X is an oxygen atom, a sulfur atom, or an imino group which may have a substituent.

R+ and R- each independently represent an alkyl group, an aralkyl group, an aryl group, or a heterocyclic residue. R5 and R may form a heterocyclic residue; R, and Rt are each independently a hydrogen atom, an alkyl group, an aralkyl group, an alkoxy group, or a halogen atom. Furthermore, R6 and R3,
Alternatively, R1 and R may form an aliphatic heterocycle.

However, when both R1 and R7 are an alkyl group or when R1 and R1 form a heterocyclic residue, this excludes the case where R1 and R and/or both are hydrogen atoms.

R5 is an alkyl group, an aralkyl group, an aryl group or a heterocyclic residue.

R4 and R+1 each independently represent a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, an aryl group, an amino group or an alkylamino group. R- and R7 may form a naphthalene ring.

Min is an integer of 0 or 1. ) To further explain the substituents in detail, the above substituent R
Among 1, R,, Rshi, ~, Rt, R number, member and R7, alkyl groups include methyl, ethyl, linear and branched propyl groups, butyl groups, pentyl, hexyl groups,
Substituents such as stearyl group; Aralkyl group refers to substituents such as benzyl group, phenethyl group, cinnamyl group, naphthylmethyl group, and henzhydryl group; Aryl group refers to substituents such as phenyl group, naphthyl group, and anthryl group. Substituent; acyclic residue refers to substituents such as pyridyl group, thiazolyl group, and benzoxacylyl group (however, R+ and R1
When forming a heterocycle, substituents such as piperidino group and morpholino group); alkylamino group refers to substituents such as ethylamino group, diethylamino group, and dibutylamino group, respectively.

The hydrazone compound of the present invention represented by the general formula (1) can be prepared by, for example, the following method.

can be manufactured.

One method is to use the general formula (II) (wherein R6, R& and R7 are the general formula (1)
), hydrazine or its mineral salt represented by and general formula (1)
This is a method in which aldehydes represented by the following are reacted in an organic solvent.

General formula (nl) (However, in the formula, R4, R-, Rs, and general formula CI)
As for the solvent, a wide variety of non-reactive organic solvents can be used, but preferably alcohols such as methanol and ethanol, dimethylformamide, dioxane, etc. can be used alone or in combination.

Another method is to combine hydrazine or its mineral acid salt represented by the general formula (IV) R& (wherein R and R7 are the same as in the general formula (1)) and the general formula (II
The aldehyde compound represented by I) is reacted in a solvent, and then a compound represented by the general formula % (in the formula, 2 represents a negative group such as a halogen atom) is reacted with a base, preferably a base. The two hydrazone compounds of the present invention can be obtained by reacting them under normal conditions.

As the solvent, a wide variety of non-reactive solvents can be used, but preferably protic solvents such as water and alcohols, or aprotic polar solvents such as dimethyl sulfoxide and dimethyl formamide.

Ketones such as acetone and methyl ethyl ketone, aromatic hydrocarbons such as benzene, toluene and xylene, ethers such as tetrahydrofuran and dioxane, chlorinated hydrocarbons such as dichloromethane and 1,2-dichloroethane, or amines such as pyridine and triethylamine. These types can be used alone or in combination. As the base, sodium hydroxide, potassium hydroxide, potassium carbonate, sodium methylate, sodium hydride, etc. are used.

Representative examples of the hydrazone compounds used in the present invention obtained by such a synthesis method are listed below.

[Hydrazone compound]

sH1 These compounds can be used alone or in combination of two or more.

The photoreceptor of the present invention contains the above-mentioned hydrazone compounds, and photoreceptors with various characteristics can be obtained depending on how these hydrazone compounds are applied. For example, in the present invention, a hydrazone compound as a charge transporting material is provided on a conductive support substrate in the same layer as a charge generating material, or a structure usually referred to as a single layer type photoreceptor, or mainly containing a charge generating material. It can be used in a structure commonly called a laminated type photoreceptor, which is formed by laminating two layers, a first layer containing a charge transport substance and a second layer mainly containing a charge transporting substance, on a conductive support substrate.

These configurations are appropriately selected depending on the polarity of the photoreceptor used. Furthermore, examples of the charge generating substance used in the present invention include the following. Inorganic optical semiconductors such as selenium, selenium alloys, CdS, ZnO, CdSe, and amorphous silicon can also be used as inorganic compounds.
Preferably, an organic charge generating substance is used.

Examples of organic charge generating substances include phthalocyanine pigments such as metal phthalocyanine and metal-free phthalocyanine, azo dyes such as monoazo dyes and disazo dyes, indigo pigments, quinacridone pigments, indanthrene pigments, xanthine dyes, and benzimidazoles. pigment,
Dyes and pigments such as perylene pigments and squalic menane dyes, eutectic complexes formed from pyrylium salt dyes and polycarbonate resins, and charge transfer complexes formed from electron-donating substances such as polyvinylcarbazole and electron-accepting substances such as TNF, etc. However, it is particularly preferable to use phthalocyanine pigments.

Since the hydrazone compound in the present invention does not have film-forming ability by itself, a binder resin is used to form it as a photosensitive layer. Furthermore, since charge generating substances and materials cannot form a film by themselves except for polymeric resins such as polyvinyl carbazole, a binder may be used as necessary.

The binder preferably used in the present invention is as follows.

Highly electrically insulating film-forming polymer.

Or it is a copolymer. Among such polymers and copolymers, binders preferably used in the present invention include phenol resins, polyester resins, vinyl acetate resins, and polycarbonate resins.

Polypeptide resin, cellulose resin, polyurethane resin, polyvinylpyrrolidone, polyethylene oxide,
Polyvinyl chloride resin, starch, polyvinyl alcohol, acrylic copolymer resin, methacrylic copolymer resin,
silicone resin, polyacrylonitrile copolymer resin,
Polyacrylamide)', polyvinylbutyral, polyvinylcarbazole, polyvinylidene chloride resin, and the like.

These polymer binders may be used alone or in combination of two or more, but the binders that can be used in the present invention are not limited to these. Further, in the photoreceptor of the present invention, a charge generation layer containing a charge generation substance as a main component is provided on the conductive support via an intermediate layer if necessary, and adjacent to the charge generation layer the charge generation layer containing a charge transport substance as a main component is provided. A stacked structure including a charge transport material may also be used. In addition, in the case of such a laminated structure, which of the charge generation layer and the charge transport layer is to be used as the upper layer is determined depending on whether the chargeability is positive or negative. Generally, when negatively charged, it is advantageous in terms of characteristics to have a charge transport layer as an upper layer. In addition, when the photoreceptor of the present invention has a laminated structure consisting of separate layers of a charge generation layer and a charge transport layer, the charge generation layer can be placed directly on the conductive support or as required with an adhesive layer or barrier layer. On top of an intermediate layer such as a single layer, ■ Vacuum deposition is performed, ■ A solution of the charge-generating substance dissolved in an appropriate solvent is applied, or ■ The charge-generating substance is dispersed finely in a solvent using a ball mill, attritor, etc. turned into
If necessary, it can be provided by a method such as coating a dispersion obtained by mixing and dispersing with a polymer binder. The polymer binder used at this time may be the same as that used for the charge transport layer.

Alternatively, it may be a single photosensitive layer comprising two hydrazone compounds according to the present invention and a binder.

Further, the charge transport material is preferably 10 to 300 parts by weight per 100 parts by weight of the binder. However, the present invention is not limited only to this range. In addition, the thickness of this photosensitive layer depends on the required photosensitivity and durability,
It is determined by the mixing ratio of the charge generating substance and the charge transporting substance to the binder, but regardless of whether it is a single layer type or a laminated type,
The thickness of the photosensitive layer on the supporting conductive substrate is 50 microns or less.

Preferably, the thickness is about 7 to 30 microns, which is suitable from the viewpoint of flexibility of the film.

The photosensitive layer can also be coated with a layer that serves as a protective layer, if necessary.

The support used in the electrophotographic photoreceptor of the present invention may be any support as long as it is endowed with conductivity, and any type of conductive layer conventionally used may be used. Specifically, metals such as aluminum, copper, stainless steel, and brass, plastics on which aluminum, indium oxide, tin oxide, etc. are vapor-deposited or laminated, or plastics with conductive particles 2 such as carbon black, tin particles, and aluminum particles dispersed therein are used. can be mentioned. Moreover, the shape may be sheet-like, cylindrical, or other shapes. Note that when using the electrophotographic photoreceptor according to the present invention,
The light source is usually a halogen lamp, or if the charge-generating substance is phthalocyanine, which has a sensitivity of 750 nm or more, a laser beam such as a gallium-aluminum-arsenide semiconductor laser (oscillation wavelength 780 nm) is used. It can also be used.

Next, the present invention will be explained in more detail with reference to synthesis examples and examples, but the present invention is not limited to the following examples. In the following examples, "parts" refer to parts by weight.

Synthesis example 1 A synthesis example of compound (1) of the present invention will be shown.

After adding 77 parts of phosphorus oxychloride to 40 parts of dimethylformamide at 15-20"C, nitrogen was added at the same temperature.

Add 54 parts of N-dibenzylaniline and heat to 50-55°C.
Stir for 4 hours. After cooling the reaction solution.

Pour into 2500 parts of ice water. The mixture is then neutralized with sodium hydroxide to a pH of 9 to 1o, cooled, filtered, washed with water, and dried to obtain 54 parts of an aldehyde having the structure shown below.

Next, 30 parts of the above aldehyde and 18 parts of hydrazine having the structure shown below were added to 150 parts of ethanol.

Then, 3 parts of acetic acid was added as a catalyst, and the mixture was stirred at 70 to 80°C for 2 hours. The reaction solution is cooled, and the precipitated crystals are filtered and washed with water. Then, after reslurrying these crystals in ammonia alkaline water,
Filtration, washing with water and drying yield 43 parts of compound (1).

Recrystallization from acetonitrile yields 41 parts of a pure product with a melting point of 185-186°C.

Synthesis example 2 A synthesis example of compound (2) of the present invention will be shown.

After adding 77 parts of phosphorus oxychloride to 50 parts of dimethylformamide at 15 to 20°C, N was added at the same temperature.

Add 33 parts of N-cyanidylaniline and heat to 60-70°C.
Stir for 3 hours. After cooling the reaction solution.

Pour into 2500 parts of ice water. The mixture is then neutralized with sodium hydroxide to a pH of 9 to 10, cooled, filtered, washed with water, and dried to obtain 32 parts of aldehyde having the structure shown below.

8 parts, 9 parts of hydrazine having the structure shown below, and 1 part of p-toluenesulfonic acid as a catalyst are added, and the mixture is stirred at 70 to 80°C for 2 hours. After cooling, filtering and drying, 22 parts of the upper part having the following structure are obtained.

Next, 2.4 parts of sodium hydroxide are added to 50 parts of dimethylformamide at 15 to 20°C, and then 20 parts of the above hydrazone are added at the same temperature. Then, 7 parts of butyl bromide are added dropwise at 20-25°C. After stirring at the same temperature for 3 hours,
The mixture is poured into 1000 parts of ice water, filtered, washed with water, and dried to obtain 22 parts of compound (3).

Synthesis example 3 A synthesis example of compound (8) of the present invention will be shown.

Synthesis Example) Using 44 parts of m-(N,N-dibutylamino)-toluene in place of 54 parts of N,N-dibenzylaniline in [1], 45 parts of an aldehyde having the following structure is obtained.

Next, 25 parts of the above aldehyde, 18 parts of hydrazine having the structure shown below, and 3 parts of acetic acid as a catalyst were added to 150 parts of ethanol, and the mixture was stirred at 70 to 80°C for 2 hours.

The reaction solution is cooled, and the precipitated crystals are filtered and washed with water. Then, the crystals are reslurried in ammonia alkaline water, filtered, washed with water, and dried to obtain 40 parts of compound (8). Recrystallized from acetonitrile, melting point 118-121℃
35 parts of pure product are obtained. A similar reaction was performed using m-(N,N-dibenzylamino)-toluene instead of m-(N,N-dibutylamino)-toluene to obtain 151-15.
Compound (3) is obtained with a melting point of 3°C.

Example 1 40 parts of copper phthalocyanine and 0.5 parts of tetranitrocopper phthalocyanine are dissolved in 500 parts of 98% concentrated sulfuric acid with thorough stirring. The molten liquid was poured into 5000 parts of water to precipitate a composition of copper phthalocyanine and tetranitrocopper phthalocyanine, which was then filtered once, washed with water, and dried at 120° C. under reduced pressure.

Next, 1 part of this composition and 2.5 parts of compound (1).

Acrylic polyol (manufactured by Takeda Pharmaceutical Co., Ltd., Takelac A)
-702) 3.6 parts, epoxy resin (manufactured by Shell Chemical Co., Ltd.,
Epon 1007) 0.5 parts, methyl ethyl ketone 1.2
1.2 parts of cellosolve acetate and 1.2 parts of cellosolve acetate were kneaded in a magnetic ball mill for 48 hours to obtain a photoconductive composition.

Next, this photoconductive composition was rolled onto the aluminum of a laminate film of a 5-micron thick aluminum foil and a 75-micron polyester film to a dry film thickness of 8 microns, and heated uniformly to 110°C. The sample was placed in a heated oven for 1 hour to prepare an electrophotographic photoreceptor.

A corona discharge was applied to the sample thus obtained at +5.7 KV, a corona gap of 10 mm, and a charging speed of 10 va/win.
Exposure is performed using a 854 tungsten light source with an illuminance of 1QLux. The amount of light irradiation required for the potential immediately before exposure to decrease by 50% at this time was defined as the sensitivity. The sample measured in this way had a maximum surface charge of 640V, a dark decay rate of 17%,
Sensitivity 1.2 Lux, seC + residual potential 20V,
Both chargeability and sensitivity were of values sufficient for practical use, and no induction was observed in 1 surface potential decay during charging exposure, and a 5-curve light decay curve was exhibited. I also made 100 copies of this photoconductor in a row using a copying machine with a positive charge, but the resulting images had excellent gradation9. A beautiful image was obtained in terms of detail intermediate color density, and there was no change in sensitivity.Furthermore, although there were scratches on the photoreceptor, a clear image without any scratches was obtained in the copied image.

Examples 2 to 4 In Example 1, compound (6) was used instead of compound (1).
, (11) and (12), respectively, Example 1
When tested in the same manner as in Example 1, both chargeability and sensitivity were of sufficient value for practical use, no induction was observed in 1 surface potential decay during charging exposure, and the repeatability was also good.

Example 5 40 parts of copper phthalocyanine and 1.5 parts of dinitrometal-free phthalocyanine are dissolved in 100 parts of 98% concentrated sulfuric acid with thorough stirring. Pour the molten liquid into 1000 parts of water,
After the phthalocyanine composition is precipitated, it is filtered once, washed with water, and dried at 120° C. under reduced pressure. 1 part of this composition, 3 parts of compound (3), 4 parts of polycarbonate resin (Kikijin Panlite L-1250) and 10 parts of tetrahydrofuran were dispersed in a ball mill, and this liquid was sprayed into an aluminum cylinder with a thickness of 10 μm. After applying.

It was dried and used as an electrophotographic photoreceptor. The electrophotographic properties of the thus obtained sample were measured in the same manner as in Example 1. The sample measured in this way had a maximum surface charge of 600V and a sensitivity of 1. I Lux, seC, its optical attenuation curve shows a 5 curve with no induction, and even in repeated photographic tests with positive charging by a copying machine, it shows an ioo.

With 0 copies, clear images with excellent gradation and no change in sensitivity were obtained in both the initial and Ill images.

Example 6 2 parts of compound (8) for 1 part of ε-type copper phthalocyanine,
Disperse 0.8 parts of triphenylmethane, 4 parts of acrylic resin, and 20 parts of cellosolve acetate in a ball mill,
The following is the same as in Example 1.

The sample was measured. The obtained light attenuation curve is 5 curves with no induction, the maximum surface potential at this time is 590 V, the dark attenuation rate is 10%, and the sensitivity is 1°7 Lux, s.
Example 7 in which the eC+ residual potential was 15 V and the same results as in Example 1 were obtained in the actual photo test. 10 parts of copper phthalocyanine obtained in Example 1.

36 parts of acrylic polyol (Takelac A-702),
A photoconductive paint was prepared by kneading a composition consisting of 5 parts of an epoxy resin (manufactured by Shell Chemical Co., Ltd.) and 50 parts of methyl ethyl ketone:cellosolve acetate (1:1) for 24 hours using a ball mill.

This paint was coated on an aluminum support to a thickness of about 1 μm to form a charge generation layer.

Next, polycarbonate resin (Panlite L-1250
) and 3 parts of polyester resin (manufactured by Gutdeyer) were mixed with tetrahydrofuran and 100 parts of toluene solvent. The weight ratio of solvents is 9:1. 9 parts of compound (2) were added together with 0.02 parts of silicone oil. Coat this solution on the charge generation layer to a thickness of about 15μ, and hold it at 80°C.
The mixture was dried to form a charge transport layer, and a laminated photoreceptor was obtained.

When this photoreceptor was corona charged at -6.5 KV for 0.2 seconds, the surface potential was -810 V, and the sensitivity was 1.
2 Lux, sec, and was an extremely highly sensitive photoreceptor.

Examples 8 to 9 In Example 7, compound (10
) and (14) were tested in the same manner as in Example 7. As in Example 7, both chargeability and sensitivity were of sufficient value for practical use, and no induction was observed in 2 surface potential attenuation upon charging exposure. Moreover, the repeatability was also good.

Example 10 X-type metal-free phthalocyanine IO part, thermosetting acrylic resin 32 parts, melamine resin 8 parts and butyl acetate:
A photoconductive paint was prepared by kneading a composition consisting of 50 parts of cellosolve acetate (1:1) in a ball mill for 24 hours, and this paint was coated on an aluminum support to a thickness of about 1 μm.

A charge generation layer was formed.

Next, in the same manner as the charge transport layer of Example 4, it was coated on the charge generation layer to a thickness of about 15μ, dried at 80°C,
A charge transport layer was formed to obtain a laminated photoreceptor.

When this photoreceptor was corona charged at -6.5KV for 0.2 seconds, the surface potential was -1200V, and the sensitivity was E%.
is 1. In I Lu, it was sec.

Example 11 98 parts of tetrahydrofuran was added to 2 parts of Guianpoule (CI21180), and the mixture was crushed and mixed in a ball mill to obtain a charge-generating pigment coating liquid. This was applied onto a polyester film on which aluminum had been vapor-deposited using a doctor blade, and air-dried to form a charge generation layer with a thickness of 0.5 μm. Next, a coating liquid for forming a charge transport layer obtained by mixing 2 parts of compound (5) synthesized according to Synthesis Example 1, 2 parts of polycarbonate (Panlite L), and 45 parts of tetrahydrofuran was applied onto the charge generation layer with a doctor. Apply with a blade and dry at 100℃ for 30 minutes to a thickness of 10μ.
to form a charge generation layer.

A photoreceptor of the present invention was made.

When this photoreceptor was corona charged at -6.5 KV for 0.2 seconds, the surface potential was 1960 ■, and the sensitivity E% was 5. I Lux, sec. [Effects of the Invention] The present invention has the above structure, and when using it,
High sensitivity even in positive and negative charging, and
There is little deterioration of the photoreceptor due to repetition, and in practical use, it has excellent charge retention power from low to high temperatures and from low humidity to high humidity, environmental friendliness with respect to sensitivity changes, and durability.

patent applicant Toyo Ink Manufacturing Co., Ltd. Continuation of page 1 @Inventor Sound board Michidori Kujira Miyako Chuo-ku Inside the company

Claims (1)

[Claims] 1. A small amount of the compound represented by the following general formula (1) (both 1 and 1)
An electrophotographic photoreceptor characterized by having a photosensitive layer containing seeds. General formula (1) (wherein, Island and R3
may form a heterocyclic residue; R, and R each independently represent a hydrogen atom, an alkyl group, an aralkyl group, an alkoxy group, or a halogen atom. Furthermore, R, and R2,
Alternatively, RJ and Rt may form an aliphatic heterocycle. However, R and R8 are both alkyl groups or R1
and 9 to form a heterocyclic residue, excluding the case where both R5 and R+ are hydrogen atoms. RI is an alkyl group, an aralkyl group, an aryl group or a heterocyclic residue. R& and R7 each independently represent a hydrogen atom, a halogen atom,
It is an alkyl group, an alkoxy group, an aryl group, an amino group or an alkylamino group. R- and R7 may form a naphthalene ring. n is an integer of 0 or 1. )