JPH05142808A - Electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To improve stability against light and ozone and keep high sensitivity in the case an azo compound or a perylene compound is used as an electric charge generating material by forming a photosensitive layer containing a specific stabilizing agent. CONSTITUTION:A photosensitive layer containing a compound selected from a group of compounds expressed by the formula I and the like as a stabilizing agent is formed on a conductive base body. In the formula I, R1-R4 may be the same or different and represent hydrogen atom, halogen atom, cyano group, nitro group, alkyl group, alkoxyl group, amino group, aryl group, aralkyl group, each possible to have a substituent; (n), (p), (q) 1-4 integer in p+q<=5; and (m) 1-5 integer. The compounds expressed by the formula I case a chain reaction due to an active singlet state oxygen or oxygen in a ground state which acts as an oxidizer and thus an electric charge generating material is prevented from being deteriorated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an organic electrophotographic photoreceptor containing a stabilizer in the photosensitive layer of the electrophotographic photoreceptor used in electrostatic copying machines, laser printers and the like.

[0002]

2. Description of the Related Art In recent years, organic photoconductors are widely used as photoconductors in image forming apparatuses such as copying machines because they are excellent in processability and economy and have a high degree of freedom in functional design. The Carlson process is widely used to form a copied image using a photoconductor. The Carlson process consists of a charging process that uniformly charges the photoconductor by corona discharge, an exposure process that exposes the document image on the charged photoconductor to form an electrostatic latent image corresponding to the document image, and an electrostatic latent image. After development with a developer containing toner, a developing step of forming a toner image, a transfer step of transferring the toner image to paper, a fixing step of fixing the transferred toner image, and a transfer step,
And a cleaning step for removing the toner remaining on the photoconductor. In order to form a high-quality image in the Carlson process, the photoconductor is required to have excellent charging properties and photosensitivity, and to have a low residual potential after exposure.

Conventionally, inorganic photoconductors such as selenium and cadmium sulfide have been known as photosensitive materials, but they have the drawbacks of toxicity and high production cost. Therefore, so-called organic photoconductors using various organic substances in place of these inorganic substances have been proposed. Such an organophotoreceptor has a photosensitive layer composed of a charge generating material that generates a charge upon exposure and a charge transporting material that has a function of transporting the generated charge. In order to satisfy various conditions desired for this organic photoreceptor, it is necessary to appropriately select these charge generating material and charge transporting material. As the charge generating material, many compounds such as azo compounds, perylene compounds, phthalocyanine compounds, quinacridone compounds, and ansanthrone compounds have been proposed.

Further, in an image forming apparatus or the like, an antioxidant is used so that the photosensitive layer is not fatigued and the charging characteristics and the photosensitive characteristics are deteriorated during repeated image forming processes such as charging, exposure and charge elimination. It has been practiced to add a stabilizer such as a light stabilizer to the photosensitive layer. As the stabilizer for the photoconductor, not only the functions unique to the stabilizer are excellent, but also the performance such as not adversely affecting the photosensitivity and the like is required, and the stabilizer having some of these performances is required. Have been proposed. For example, as antioxidants, hindered phenols, paraphenylenediamines, hydroquinones, organic sulfur compounds, organic phosphorus compounds, etc. have been proposed.

[0005]

However, none of the above stabilizers is sufficient to impart oxidation resistance and light stability of the photosensitive layer, and as a result, the photosensitive characteristics of the photoreceptor are maintained. There was a problem that I could not. Further, all of the above conventional charge generating materials have poor charging characteristics, photosensitive characteristics, etc. during repeated use, and the photoreceptors using these charge generating materials have insufficient sensitivity and durability. There was a problem of becoming.

In particular, in the photoconductor using an azo compound or a perylene compound as the charge generating material, the charge generating material is deteriorated by light or ozone during operation of the image forming apparatus and the surface potential is lowered. .. Therefore, an object of the present invention is to provide a highly sensitive electrophotographic photosensitive member having improved stability to light and ozone when an azo compound or a perylene compound is used as a charge generating material.

[0007]

In order to solve the above-mentioned problems, the electrophotographic photosensitive member of the present invention comprises a general formula (I) as a stabilizer on a conductive substrate:

[0008]

[Chemical 5]

[Wherein R ¹ , R ² , R ³ and R ⁴ are
The same or different, hydrogen atom, halogen atom, cyano group, nitro group, alkyl group which may have a substituent,
It represents an alkoxy group, an amino group, an aryl group or an aralkyl group, n, p and q each represent an integer of 1 to 4, and m represents 1 to
Indicates an integer of 5. However, p + q is 5 or less. ] General formula (II):

[0010]

[Chemical 6]

[In the formula, R ⁵ represents a hydrogen atom, an alkyl group or an alkoxy group, and X represents a halogen atom, a cyano group or a nitro group. ] General formula (III):

[0012]

[Chemical 7]

[In the formula, R ⁶ , R ⁷ and R ⁸ are the same or different and each represents a hydrogen atom, an alkyl group, an alkoxy group, an alkylamino group or an aryl group. ] And general formula (IV):

[0014]

[Chemical 8]

[Wherein R ⁹ , R ¹⁰ , R ¹¹ and R ¹² are
The same or different, a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group or an aryl group is shown. n is 1 to
Indicates an integer of 4. ] A photosensitive layer containing at least one compound selected from the group consisting of] is provided. The compounds represented by the above general formulas (I) to (IV) are oxidized by active species singlet oxygen ( ¹ O ₂ ) or ground state oxygen (having reactivity as a biradical (.O.O.)). The agent can be prevented from causing a chain reaction and deteriorating the charge generation material.

For example, when an azo compound is used as the charge generating material, the equilibrium between the azo type and the hydrazone type significantly affects the photostability of the photoconductor, but the above general formulas (I) to ( The compound represented by IV) can prevent the photobleaching product from being isolated from the hydrazone type by the nin type reaction of singlet oxygen. That is, the general formula (I) ~
Quenching such as singlet oxygen, in which the compound represented by (IV) serves as an oxidizing agent, can be performed. Among them, the deterioration of the azo compound or the perylene compound can be prevented.

For this reason, a photoreceptor using an azo compound or a perylene compound as a charge generating material is
The surface potential can be prevented from lowering even after repeated use, and it is possible to stably maintain high sensitivity even for long-term exposure or exposure at high temperature, and to obtain a product with excellent light stability. .. Examples of the alkyl group include alkyl groups having 1 to 6 carbon atoms such as methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, tert-butyl group, pentyl group and hexyl group.

The alkoxy group includes, for example, a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, a butoxy group, an isobutoxy group, a tert-butoxy group, a pentyloxy group, a hexyloxy group and the like having 1 to 6 carbon atoms. The group can be raised. Examples of the aryl group include a phenyl group, a tolyl group, a xylyl group, a biphenyl group, a naphthyl group, an anthryl group and a phenanthryl group.

Examples of the aralkyl group include benzyl group, α-phenethyl group, β-phenethyl group, 3-phenylpropyl group, benzhydryl group and trityl group. As the substituent which may be substituted on the amino group,
Examples thereof include an alkyl group, an alkenyl group, an aryl group and an alkoxy group.

The anion represented by X is, for example,
Examples thereof include anions such as halogen atom, oxygen halide and hydrohalic acid. The compounds represented by the above general formulas (I) to (IV) can be synthesized by a conventionally known method. Specific compounds include, for example, the following formulas (1) to (12)
The compound represented by

[0021]

[Chemical 9]

[0022]

[Chemical 10]

[0023]

[Chemical 11]

[0024]

[Chemical 12]

[0025]

[Chemical 13]

The compounds represented by the above general formulas (I) to (IV) used as a stabilizer for the photoconductor are blended in a proportion of 0.05 to 150 parts by weight with respect to the charge generating material. .. If the blending ratio exceeds 150 parts by weight, the compound inhibits the generation of electric charge, and conversely if the blending ratio is less than 0.05 part by weight, the quenching action of singlet oxygen and the like by the compound is insufficient. become.

Further, the organic photosensitive layer contains the above general formula (I)
In addition to the compound represented by (IV), a sensitizer, a fluorene compound, an antioxidant, a deterioration inhibitor such as an ultraviolet absorber,
Additives such as plasticizers may be included. Further, in order to improve the sensitivity of the charge generation layer, known sensitizers such as terphenyl, halonaphthoquinones and acenaphthylene may be used in combination with the charge generation material.

The constitution of the present invention can be applied to both so-called single-layer type and laminated type electrophotographic photoconductors. To obtain a single-layer type photoreceptor, a compound represented by the above general formulas (I) to (IV) as a stabilizer, a charge generating material,
A photosensitive layer containing a charge transport material and a binder resin may be formed on the conductive substrate by means of coating or the like.

In order to obtain a laminated type photoreceptor, a charge containing a compound represented by the above general formulas (I) to (IV) and a charge generating material is formed on a conductive substrate by means such as coating. A charge generation layer may be formed, and a charge transport layer containing a charge transport material and a binder resin may be formed on the charge generation layer. Also,
Conversely to the above, a charge transport layer similar to the above may be formed on the conductive substrate, and then a charge generating layer similar to the above may be formed by means such as coating. Further, the charge generation layer may be formed by dispersing and applying a charge generation material and a charge transport material in a binder resin.

As the charge generating material, an azo compound or a perylene compound is preferably used. The azo compound, for example, the following general formula (a1) ~ (a15)
The compound represented by

[0031]

[Chemical 14]

[0032]

[Chemical 15]

[Wherein R ⁵⁰ represents an alkyl group or an aryl group which may have a substituent, and Y ¹ and Y
² is the same or different and represents a hydrogen atom, a halogen atom, a cyano group, an alkyl group or an alkoxy group, and A represents a coupler residue. ]

[0034]

[Chemical 16]

[In the formula, Y ¹ , Y ² and Y ³ are the same or different and each represents a hydrogen atom, a halogen atom, a cyano group, an alkyl group or an alkoxy group, and A is the same as defined above. ]

[0036]

[Chemical 17]

[In the formula, R ⁵¹ hydrogen atom, halogen atom,
Represents an alkyl group which may have a substituent or a cyano group, D represents an oxygen atom, a sulfur atom or an imino group,
l represents an integer of 0 or 1, and A is the same as above. ]

[0038]

[Chemical 18]

[In the formula, Y ¹ and Y ² are the same or different and each represents a hydrogen atom, a halogen atom, a cyano group or an alkyl group which may have a substituent, and A is the same as defined above. ]

[0040]

[Chemical 19]

[In the formula, R ⁵² represents an alkyl group which may have a hydrogen substituent, an aryl group which may have a substituent or a heterocyclic group, and l and A are the same as the above]

[0042]

[Chemical 20]

[In the formula, R ⁵³ and R ⁵⁴ are the same or different and each represents a hydrogen atom, a halogen atom, a cyano group, an alkyl group which may have a substituent, an aryl group or an alkoxy group, and D and A are the same as those described above. Is the same as. ]

[0044]

[Chemical 21]

[In the formula, R ⁵⁵ and R ⁵⁶ are the same or different and each represents a hydrogen atom, a halogen atom, a cyano group, an alkyl group which may have a substituent, an aryl group or an alkoxy group, and A is the same as defined above. Is. ]

[0046]

[Chemical formula 22]

[Wherein R ⁵⁷ , R ⁵⁸ , R ⁵⁹ , R ⁶⁰ , R ⁶¹ and R ⁶² are the same or different and each represents a hydrogen atom, a halogen atom, an alkyl group or an alkoxy group, and A is the same as defined above. is there. ]

[0048]

[Chemical formula 23]

[In the formula, R ⁶³ and R ⁶⁴ are the same or different and each represents a hydrogen atom, a halogen atom, a cyano group, a nitro group,
It represents an alkyl group, an aryl group or an alkoxy group which may have a substituent, Ar represents an aryl group which may have a substituent, m represents 0 or 1, and A is the same as defined above. ]

[0050]

[Chemical formula 24]

[Wherein R ⁶⁵ , R ⁶⁶ , R ⁶⁷ and R ⁶⁸ are
The same or different, it shows a hydrogen atom, a halogen atom, an alkyl group, an aryl group, or an alkoxy group, and A is the same as the above. ]

[0052]

[Chemical 25]

[In the formula, R ⁶⁹ and R ⁷⁰ are the same or different and each represents a hydrogen atom, a halogen atom, an alkyl group, an aryl group or an alkoxy group, and D and A are the same as defined above. In each of the above formulas, examples of the aryl group include the same groups as described above. As the alkyl group, in addition to the above groups, for example, octyl group, tert-octyl group, decyl group, hexadecyl group, dodecyl group, 2-hydroxyethyl group, carboxymethyl group, cyanomethyl group, 2-methoxyethyl group, Benzyl group, 2-phenylmethyl group, trifluoromethyl group, hydroxymethyl group, methoxymethyl group, dicyanomethyl group, aminomethyl group, N-methylaminomethyl group, mercaptomethyl group, methylthiomethyl group,
Examples thereof include N, N-dimethylaminomethyl group, chloromethyl group and bromomethyl group.

As the alkoxy group, in addition to the above groups,
For example, heptyloxy group, octyloxy group, nonyloxy group, 2-hydroxyethoxy group, carboxymethoxy group, cyanomethoxy group, 2-methoxyethoxy group,
Benzyloxy group, 2-methylphenoxy group, trifluoromethoxy group, hydroxymethoxy group, methoxymethoxy group, dicyanomethoxy group, aminomethoxy group, N-
Examples thereof include a methylaminomethoxy group, a mercaptomethoxy group, a methylthiomethoxy group, an N, N-dimethylaminomethoxy group, a chloromethoxy group and a bromomethoxy group.

The heterocyclic group is, for example, a thienyl group,
Pyrrolyl group, pyrrolidinyl group, oxazolyl group, isoxazolyl group, thiazolyl group, isothiazolyl group, imidazolyl group, 2H-imidazolyl group, pyrazolyl group, triazolyl group, tetrazolyl group, pyranyl group, pyridyl group, piperidyl group, piperidino group, 3-morpholinyl group Group, morpholino group and the like.

Examples of the coupler residue represented by A include the groups represented by the general formulas (a) to (g).

[0057]

[Chemical formula 26]

In each formula, R ³⁰ represents a carbamoyl group, a sulfamoyl group, an allofanoyl group, an oxamoyl group, an anthraniloyl group, a carbazoyl group, a glycyl group, a hydantoyl group, a phthalamoyl group, and a succinamoyl group. These groups include a halogen atom, a phenyl group which may have a substituent, a naphthyl group which may have a substituent, a nitro group, a cyano group, an alkyl group, an alkenyl group, a carbonyl group, a carboxyl group and the like. It may have a substituent.

R ³¹ represents an atomic group necessary for forming an aromatic ring, a polycyclic hydrocarbon or a heterocyclic ring by condensing with R ³⁰ and the benzene ring having a hydroxyl group, and these rings are as described above. You may have the same substituent. R ³² represents an oxygen atom, a sulfur atom or an imino group. R ³³ represents a divalent chain hydrocarbon or aromatic hydrocarbon, and these groups may have the same substituents as described above.

R ³⁴ represents an alkyl group, an aralkyl group, an aryl group or a heterocyclic group, and these groups may have the same substituents as described above. R ³⁵ is a divalent chain hydrocarbon, an aromatic hydrocarbon, or the following formula (h) in the above general formulas (e) and (f).

[0061]

[Chemical 27]

It represents an atomic group necessary for forming a heterocycle together with the moiety represented by, and these rings may have the same substituents as described above. R ³⁶ is a hydrogen atom, an alkyl group,
It represents an amino group, a carbamoyl group, a sulfamoyl group, an allofanoyl group, a carboxyl group, an ester of a carboxyl group, an aryl group or a cyano group, and groups other than a hydrogen atom may have the same substituents as described above.

R ³⁷ represents an alkyl group or an aryl group, and these groups may have the same substituents as described above.
Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group and a te group.
rt-butyl group, pentyl group, hexyl group, etc., having 1 carbon atom
The lower alkyl groups of 6 are mentioned.

As the aryl group, for example, a phenyl group,
Examples thereof include a tolyl group, a xylyl group, a biphenyl group, a naphthyl group, an anthryl group and a phenanthryl group. As the alkenyl group, for example, vinyl group, allyl group, 2-butenyl group, 3-butenyl group, 1-methylallyl group, 2-
Examples thereof include lower alkenyl groups having 2 to 6 carbon atoms such as pentenyl group and 2-hexenyl group.

Examples of the halogen atom include chlorine atom, bromine atom, iodine atom and fluorine atom. In R ³¹ , the atomic group necessary for forming an aromatic ring by condensing with R ³⁰ and a benzene ring having a hydroxyl group is, for example, an alkylene group such as a methylene group, an ethylene group, a propylene group or a butylene group. Be done.

The aromatic ring formed by the condensation of R ³¹ with R ³⁰ and a benzene ring having a hydroxyl group is
Examples thereof include naphthalene ring, anthracene ring, phenanthrene ring, pyrene ring, chrysene ring, and naphthacene ring. In R ³¹ , the atomic group necessary for condensing with R ³⁰ and a benzene ring having a hydroxyl group to form a polycyclic hydrocarbon is, for example, a methylene group, an ethylene group, a propylene group, a butylene group, or a carbon atom. Examples include alkylene groups of the numbers 1 to 4.

The polycyclic hydrocarbon formed by the condensation of R ³¹ with R ³⁰ and a benzene ring having a hydroxyl group is, for example, a carbazole ring, a benzocarbazole ring,
Examples include a dibenzofuran ring. Further, in R ³¹ , an atomic group necessary for forming a heterocycle by condensing with R ³⁰ and a benzene ring having a hydroxyl group is, for example, a benzofuranyl group, a benzothiophenyl group, an indolyl group,
1H-indolyl group, bezoxazolyl group, benzothiazolyl group, 1H-indaryl group, benzimidazolyl group, chromenyl group, chromanyl group, isochromanyl group,
Quinolinyl group, isoquinolinyl group, cinnolinyl group, phthalazinyl group, quinazonilyl group, quinoxalinyl group, dibenzofuranyl group, carbazolyl group, xanthenyl group,
Examples thereof include an acridinyl group, a phenanthridinyl group, a phenazinyl group, a phenoxazinyl group and a thianthrenyl group.

The aromatic heterocyclic group formed by the condensation of R ³¹ with R ³⁰ and a benzene ring having a hydroxyl group includes, for example, a thienyl group, a furyl group, a pyrrolyl group, an oxazolyl group, an isoxazolyl group and a thiazolyl group. , Isothiazolyl group, imidazolyl group, pyrazolyl group, triazolyl group, tetrazolyl group, pyridyl group and thiazolyl group. In addition, it may be a heterocyclic group condensed with another aromatic ring (for example, a benzofuranyl group, a benzimidazolyl group, a benzoxazolyl group, a benzothiazolyl group, a quinolyl group).

In the above R ³³ and R ³⁵ , examples of the divalent chain hydrocarbon include ethylene group, propylene group and butylene group, and examples of the divalent aromatic hydrocarbon include phenylene group, naphthylene group, Examples thereof include a phenanthrylene group. Examples of the heterocyclic group for R ³⁴ include a pyridyl group, a pyrazyl group, a thienyl group, a pyranyl group and an indolyl group.

In R ³⁵ , the atomic group necessary for forming a heterocycle with the moiety represented by the formula (h) is, for example, phenylene group, naphthylene group, phenanthrylene group, ethylene group, propylene group, butylene. Examples include groups. Examples of the aromatic heterocyclic group formed by R ³⁵ and the portion represented by the formula (h) include a benzimidazole group, a benzo [f] benzimidazole group, a dibenzo [e, g] benzimidazole group. Group, benzopyrimidine group and the like. These groups may have the same substituents as described above.

Examples of the carboxyl group ester represented by R ³⁶ include methyl ester, ethyl ester, propyl ester and butyl ester. Specific examples of the coupler residue A represented by the above general formulas (a) to (g) include the following groups.

[0072]

[Chemical 28]

[0073]

[Chemical 29]

[0074]

[Chemical 30]

[0075]

[Chemical 31]

Specific examples of the azo compound include compounds represented by the following formulas (b1) to (b12).

[0077]

[Chemical 32]

[0078]

[Chemical 33]

[0079]

[Chemical 34]

[0080]

[Chemical 35]

Further, specific examples of the perylene compound include compounds represented by the following formulas (c1) to (c7).

[0082]

[Chemical 36]

[0083]

[Chemical 37]

[0084]

[Chemical 38]

In the electrophotographic photoreceptor of the present invention, the compounds represented by the general formulas (I) to (IV) as the stabilizer and the azo compound or the perylene compound as the charge generating material are used. Besides being used alone, they can be used in combination with conventionally known charge generating materials. Examples of other charge generating materials include amorphous silicon, anthanthrone pigment, phthalocyanine pigment, indigo pigment, triphenylmethane pigment, slene pigment, toluidine pigment, pyrazoline pigment, quinacridone pigment, and the like. Be done. These charge generating materials are used alone or in combination of two or more so as to have an absorption wavelength region in a desired region.

As the charge transport material, conventionally known materials can be used, for example, oxadiazole compounds such as 2,5-di (4-methylaminophenyl) -1,3,4-oxadiazole, Styryl compounds such as 9- (4-diethylaminostyryl) anthracene, carbazole compounds such as polyvinylcarbazole, pyrazoline compounds such as 1-phenyl-3- (p-dimethylaminophenyl) pyrazoline, hydrazone compounds, triphenylamine Compounds, indole compounds, oxazole compounds, isoxazole compounds, thiazole compounds, thiadiazole compounds, imidazole compounds, pyrazole compounds, nitrogen-containing cyclic compounds such as triazole compounds, and condensed polycyclic compounds. Be done. These charge transport materials are used alone or in combination of two or more. Note that the binder resin is not always necessary when using a charge transporting material having film-forming properties such as polyvinylcarbazole.

Various resins can be used as the binder resin used in the above-mentioned single-layer type or multi-layer type photoreceptors. For example, a styrene-based polymer, a styrene-butadiene copolymer, a styrene- Acrylonitrile copolymer, styrene-maleic acid copolymer, acrylic polymer, styrene-acrylic copolymer, polyethylene, ethylene vinyl acetate copolymer, chlorinated polyethylene, polyvinyl chloride, polypropylene, vinyl chloride-vinyl acetate Thermoplastic resin such as copolymer, polyester, alkyd resin, polyamide, polyurethane, polycarbonate, polyarylate, polysulfone, diallyl phthalate resin, ketone resin, polyvinyl butyral resin, polyether resin, silicone resin, epoxy resin, phenol resin, Urea resin, Min resin, other crosslinking thermosetting resin, further epoxy acrylates, urethane - various polymers, such as photo-curable resin such as acrylate. These binder resins may be used alone or in combination of two or more.

A solvent is used when the charge generation layer and the charge transport layer are formed by a coating method or the like. As this solvent, various organic solvents can be used, for example, alcohols such as methanol, ethanol, isopropanol and butanol, aliphatic hydrocarbons such as n-hexane, octane and cyclohexane, benzene, toluene, Aromatic hydrocarbons such as xylene, halogenated hydrocarbons such as dichloromethane, dichloroethane, carbon tetrachloride and chlorobenzene, ethers such as dimethyl ether, diethyl ether, tetrahydrofuran, ethylene glycol dimethyl ether and diethylene glycol dimethyl ether, ketones such as acetone, methyl ethyl ketone and cyclohexanone. Examples thereof include various solvents such as compounds, esters such as ethyl acetate and methyl acetate, dimethylformaldehyde, dimethylformamide, dimethylsulfoxide, and the like. These solvents may be used alone or in combination of two or more.

Further, a surfactant, a leveling agent or the like may be used in order to improve the dispersibility of the charge generating material or the charge transporting material and the dyeing property. Various materials having conductivity can be used as the conductive substrate. For example, a simple substance of metal such as aluminum, copper, tin, platinum, gold, silver, vanadium, molybdenum, chromium, cadmium, titanium, nickel, palladium, indium, stainless steel, or brass, or a plastic material in which the above metal is vapor-deposited or laminated. , Glass coated with aluminum iodide, tin oxide, indium oxide and the like.

The conductive substrate may be in the form of a sheet or a drum, as long as the substrate itself has conductivity or the surface of the substrate has conductivity. As the substrate, a substrate having sufficient mechanical strength when used is preferable. The addition amount of the charge generating material in the single-layer type photosensitive layer is 0.1 to 50 parts by weight based on 100 parts by weight of the binder resin.
Suitably, it is 0.5 to 30 parts by weight. The addition amount of the charge transport material in the single-layer type photosensitive layer is 40 to 200 with respect to 100 parts by weight of the binder resin.
Suitably, parts by weight, preferably 50 to 150 parts by weight.

The addition amount of the charge transport material in the laminated charge transport layer is 10 to 100 parts by weight of the binder resin.
Suitably 500 parts by weight, preferably 25 to 200 parts by weight. The amount of the charge generating material added to the laminated charge generating layer is appropriately 5 to 500 parts by weight, preferably 10 to 300 parts by weight, based on 100 parts by weight of the binder resin.

The film thickness of the photosensitive layer formed is preferably about 5 to 100 μm, and more preferably about 15 to 25 μm in the case of a single layer type. In the case of a laminated type, the thickness of the charge generation layer is preferably about 0.01 to 5 μm, particularly about 0.1 to 3 μm, and the thickness of the charge transport layer is about 2 to 100 μm, particularly about 5 to 50 μm. Is preferred.

When the charge generation layer and the charge transport layer are formed by a coating method, the charge generation material and the binder resin may be formed by a known method such as roll mill, ball mill, attritor, paint shaker or ultrasonic wave. It may be prepared by dispersing and mixing using a disperser or the like, and applying and drying this by a known means. Further, the charge generation layer may be formed by depositing the above charge generation material.

In the case of the single-layer type electrophotographic photosensitive member, between the conductive substrate and the photosensitive layer, and in the laminated type electrophotographic photosensitive member, the conductive substrate and the charge generation layer are provided. A barrier layer may be formed between the electrically conductive substrate and the charge transport layer and between the charge generation layer and the charge transport layer as long as the characteristics of the photoreceptor are not impaired. A protective layer may be formed on the surface of the photoconductor.

[0095]

The present invention will be described in detail below with reference to examples and comparative examples. Example 1 As a stabilizer, 0.05% of the compound represented by the above formula (1) was used.
Parts by weight, 10 parts by weight of the azo pigment represented by the formula (b7) as a charge generating material, and the following formula as a charge transporting material.
80 parts by weight of DEH represented by (B), 100 parts by weight of polycarbonate as a binder resin, and a predetermined amount of methylene chloride as a solvent are mixed and dispersed using a paint shaker, and applied for a single-layer type photosensitive layer. The liquid was adjusted.

[0096]

[Chemical Formula 39]

This coating solution was applied to the surface of an aluminum foil using a wire bar, and a sheet-shaped product having an outer diameter of 78
mm-230 mm long aluminum tube with a drum-shaped coating applied by dipping on the surface at 60 ° C in the dark
And heated and dried for 120 minutes to prepare a positively charged electrophotographic photosensitive member having a single-layer type photosensitive layer each having a film thickness of 18 μm.

Example 2 The procedure of Example 1 was repeated except that the stabilizer used in Example 1 was 0.1 part by weight and the charge generating material was used in place of the azo pigment represented by the formula (b8). In the same manner as in Example 1, a single layer type photoreceptor was produced. Example 3 The same as Example 1 except that the stabilizer used in Example 1 was changed to 1 part by weight and the charge generating material was used in place of the azo pigment represented by the formula (b9). Thus, a single-layer type photoconductor was prepared.

Example 4 In place of the stabilizer and the charge generating material used in Example 1, 5 parts by weight of the compound represented by the above formula (2) and the above formula were used.
A single-layer type photoreceptor was produced in the same manner as in Example 1 except that the azo pigment represented by (b10) was used. Example 5 Instead of the stabilizer and the charge generating material used in Example 1, 20 parts by weight of the compound represented by the formula (3) and the azo pigment represented by the formula (b11) were used. A single-layer type photoreceptor was produced in the same manner as in Example 1 except for the above.

Example 6 Instead of the stabilizer and the charge generating material used in Example 1, 50 parts by weight of the compound represented by the formula (4) and the azo pigment represented by the formula (b12) were used. A single-layer type photoreceptor was prepared in the same manner as in Example 1 except that was used. Example 7 Instead of the stabilizer and the charge generating material used in Example 1, 0.1 part by weight of the compound represented by the formula (5) and the azo pigment represented by the formula (b1) were used. A single-layer type photoreceptor was produced in the same manner as in Example 1 except that it was used.

Example 8 Instead of the stabilizer and the charge generating material used in Example 1, 0.1 part by weight of the compound represented by the formula (6) and the formula (b2) were used. A single-layer type photoreceptor was produced in the same manner as in Example 1 except that the azo pigment was used. Example 9 Instead of the stabilizer and the charge generating material used in Example 1, 0.1 part by weight of the compound represented by the formula (7) and the azo pigment represented by the formula (b3) were used. A single-layer type photoreceptor was produced in the same manner as in Example 1 except that it was used.

Example 10 Instead of the stabilizer and the charge generating material used in Example 1, 0.1 part by weight of the compound represented by the formula (8) and the formula (b4) were used. A single-layer type photoreceptor was produced in the same manner as in Example 1 except that the azo pigment was used. Example 11 In place of the stabilizer and the charge generating material used in Example 1, 5 parts by weight of the compound represented by the above formula (9) and the above formula
A single-layer type photoreceptor was produced in the same manner as in Example 1 except that the azo pigment represented by (b5) was used.

Example 12 Instead of the stabilizer and the charge generating material used in Example 1, 10 parts by weight of the compound represented by the formula (10) and the azo pigment represented by the formula (b6) were used. A single-layer type photoreceptor was prepared in the same manner as in Example 1 except that was used. Example 13 In place of the stabilizer and the charge generating material used in Example 1, 1 part by weight of the compound represented by the formula (11) and the compound represented by the formula
A single-layer type photoreceptor was produced in the same manner as in Example 1 except that the azo pigment represented by (b1) was used.

Example 14 In place of the stabilizer and the charge generating material used in Example 1, 3 parts by weight of the compound represented by the above formula (12) and the above formula were used.
A single-layer type photoreceptor was produced in the same manner as in Example 1 except that the azo pigment represented by (b2) was used. Example 15 In place of the stabilizer and the charge generating material used in Example 1, 1 part by weight of the compound represented by the formula (1)
A single-layer type photoreceptor was produced in the same manner as in Example 1 except that the azo pigment represented by (c2) was used.

Example 16 In place of the stabilizer and the charge generating material used in Example 1, 5 parts by weight of the compound represented by the above formula (2) and the above formula were used.
A single-layer type photoreceptor was produced in the same manner as in Example 1 except that the azo pigment represented by (c4) was used. Example 17 Instead of the stabilizer and the charge generating material used in Example 1, 10 parts by weight of the compound represented by the formula (3) and the azo pigment represented by the formula (c6) were used. A single-layer type photoreceptor was produced in the same manner as in Example 1 except for the above.

Comparative Examples 1 to 17 Single layer type photoreceptors were prepared in the same manner as in the above Examples except that the stabilizer was not used. Each of the above examples,
The following tests were carried out on the electrophotographic photosensitive member of the comparative example to evaluate its characteristics.

Measurement of initial surface potential Electrostatic copying tester (EPA-810 manufactured by Kawaguchi Electric Co., Ltd.)
0) is used to apply a voltage to each electrophotographic photosensitive member to positively charge its surface, and the initial surface potential Vs.p.
(V) was measured. Measurement of half-dose exposure and residual potential The electrophotographic photoreceptor charged in the above-mentioned measurement of the initial surface potential was exposed under a condition of exposure intensity of 10 lux by using a white halogen lamp which is an exposure light source of an electrostatic copying tester. The half-exposure amount E1 / 2 (lux.sec) was calculated by obtaining the time required for the surface potential to become 1/2 after the exposure.

The surface potential was measured 5 seconds after the start of the exposure, and the residual potential Vr.p. (V) was measured. Measurement of Light Stability The above drum-shaped electrophotographic photosensitive member was loaded in an electrostatic copying machine (Model No. DC-111 manufactured by Mita Kogyo Co., Ltd.) to perform continuous copying of 1000 sheets, and then, in the same manner as above. The initial surface potential V1s.p. (V) after repeated exposure was measured. Then, the difference ΔVs.p. (V) from the surface potential Vs.p.

The results of each Example are shown in Table 1 below, and the results of each Comparative Example are shown in Table 2 below. The stabilizers and charge generation materials used are indicated by the numbers in the above formula.

[0110]

[Table 1]

[0111]

[Table 2]

From the results shown in Tables 1 and 2, the electrophotographic photoreceptors of Examples 1 to 17 having the constitution of the present invention have a surface potential [Vs.p.], a half exposure amount [E1 / 2] and a residual amount. Potential [V
rp] is almost the same as the conventional photoconductors of Comparative Examples 1 to 17, but the light stability [ΔV s.p.] is smaller than that of the photoconductors of Comparative Examples, and therefore, it is used repeatedly. However, the surface potential change of the photoconductor was small, and it was found that each of them had excellent durability.

[0113]

As described above, the electrophotographic photoreceptor of the present invention has a high sensitivity because it contains a stabilizer capable of preventing deterioration due to light or ozone in the photosensitive layer. ,
Moreover, a product having excellent durability can be obtained.

Claims (1)

[Claims] 1. A general formula as a stabilizer on a conductive substrate.
(I): [Chemical 1] [Wherein R ¹ , R ² , R ³ and R ⁴ are the same or different and each represents a hydrogen atom, a halogen atom, a cyano group, a nitro group,
An alkyl group which may have a substituent, an alkoxy group,
An amino group, an aryl group or an aralkyl group, n,
p and q show the integer of 1-4, m shows the integer of 1-5. However, p + q is 5 or less. ] General formula (II): [In the formula, R ⁵ represents a hydrogen atom, an alkyl group or an alkoxy group, and X represents a halogen atom, a cyano group or a nitro group. ] General formula (III): [In the formula, R ⁶ , R ⁷ and R ⁸ are the same or different and each represents a hydrogen atom, an alkyl group, an alkoxy group, an alkylamino group or an aryl group. ] And the general formula (IV): [In the formula, R ⁹ , R ¹⁰ , R ¹¹ and R ¹² are the same or different and each represents a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group or an aryl group. n shows the integer of 1-4. ] An electrophotographic photoreceptor provided with a photosensitive layer containing at least one compound selected from the group consisting of: