JPH06273952A - Electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To obtain the excellent electrophotographic performance, that is, high sensitivity, low residual electric potential, good picture characteristic, which uses the charge transfer material having electron transfer property by incorporating a specified compd. in a photosensitive layer. CONSTITUTION:The compd. expressed by the formula is incorporated in the photosensitive layer 4 as the charge transfer material 7. In the formula, Y is NO2, CN, CF3, COR2, COOR2, CONHR2, halogen, SOR2, SO2R2 or OCOR2, Z is alkyl, aryl group, OR2, OH or N(R2)2, R1 is alkyl group, R2 is alkyl or aryl group. (m) is integer >=2, (n) is 0 or a positive integer, the sum of (m) and (n) is integer 2 8. The group of plural numbers expressed by Y, Z and R2 may be the same or different with each other. When the substd. group is alkyl group or contains alkyl group, the alkyl group is straight-chain, branch- chain and the alicyclic ring which may be crosslinked.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to an electrophotographic photosensitive member for forming an electrostatic latent image. More specifically, it relates to an electrophotographic photoreceptor having a layer containing a compound having an electron transporting ability.

[0002]

2. Description of the Related Art Conventionally, electrophotographic photoreceptors using organic photoconductors have been variously studied because of their advantages such as pollution-free, high productivity and low cost. It is put to practical use as a photoreceptor. These electrophotographic photoreceptors include a laminated type and a single layer type, but a photoreceptor using an organic photoconductor generally has a charge generation layer that generates a charge by light irradiation and a charge that transports the generated charge. It has a laminated structure consisting of a transport layer. In this case, as the charge transport material used in the charge transport layer, a polymer material such as poly-N-vinylcarbazole or a low molecular weight compound such as pyrazoline, hydrazone or triphenylamine derivative is used.

However, since all of these charge-transporting substances have a hole-transporting ability, most of the developing systems adopting a negative charge on the surface of the photoconductor are adopted.
For this reason, the toner that has been conventionally used in high-speed machines cannot be used, and there are few high-quality toners at present. Further, when the surface of the photoconductor is negatively charged as described above, there is a problem that not only the ozone is generated due to the reaction with oxygen in the air at the time of charging to harm the environment but also the surface of the photoconductor is deteriorated.

On the other hand, a positive charging laminated photoreceptor having a charge transport layer on the lower side and a charge generation layer on the upper side has been developed by reversing the layer structure of the photosensitive layer of the laminated photoreceptor. Since the charging potential is low and the printing durability is poor, a protective layer is further provided on the charge generation layer.

[0005]

In order to solve the above problems, a photoconductor in which a charge transport material having an electron transporting property is used in a charge transport layer and the surface of the photoconductor is positively charged. Should be configured. 2,4,7-Trinitro-9-fluorenone is known as such an electron-transporting material, but its solubility is poor and it is not possible to obtain practical sensitivity by combining it with an existing charge-generating substance. It was In addition, 2, 4,
As a result of improved studies on 7-trinitro-9-fluorenone, in recent years, an electron transporting substance having a solubilizing group introduced into an electron acceptor structure has been proposed. For example, Japanese Patent Laid-Open No. 1-206349
No. 2, No. 2-135362, No. 2-214866, No. 3-290666 and “Japan Hardcopy'92” Proceedings, 173, (1992). However, in the present situation, when any of the compounds is combined with an existing charge generating substance to form a photoreceptor, the sensitivity is still insufficient in practical use, and a good image cannot be obtained.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems.
An object of the present invention is to provide an electrophotographic photosensitive member using a charge transporting material having an electron transporting ability.

Another object of the present invention is to provide a laminate type electrophotographic photoreceptor for positive charging, which has excellent electrophotographic performance, that is, high sensitivity, low residual potential and good image characteristics.

[0008]

As a result of research, the present inventors have found that the object of the present invention can be achieved by any of the following electrophotographic photoreceptors. That is, in an electrophotographic photoreceptor having a photosensitive layer provided on a conductive support, the following general formulas [I], [II], and
The object of the present invention can be achieved by incorporating any of the compounds represented by [III] or [IV].

[0009]

[Chemical 5]

In the formula, Y is NO ₂ , CN, CF ₃ , CO
R ₂ , COOR ₂ , CONHR ₂ , halogen, SOR ₂ , S
Represents O ₂ R ₂ or OCOR ₂ , Z represents an alkyl group, an aryl group, OR ₂ , OH or N (R ₂ ) ₂ , R ₁ represents an alkyl group, and R ₂ represents an alkyl group or an aryl group . m represents an integer of 2 or more, n represents 0 or a positive integer, and the sum of m and n represents an integer of 2 to 8. The plurality of groups represented by Y, Z and R ₂ may be the same or different.

When the substituent in the above general formula [I] is an alkyl group or contains an alkyl group, the alkyl group may be linear, branched or crosslinked unless otherwise specified. Cyclic ring, which may be substituted or may contain an unsaturated bond (eg, methyl, ethyl, iso-propyl, t-butyl, pentyl, 2-ethylhexyl, dodecyl, allyl, oleyl, benzyl) , Hydroxyethyl, methoxyethyl, phenoxyethyl, cyclopentyl, cyclohexyl, norbornyl).

When the substituent in the above general formula [I] is an aryl group or contains an aryl group, the aryl group may be substituted unless otherwise specified, and a monocyclic or condensed ring aryl group ( For example, phenyl, 1-naphthyl, p-tolyl, p-chlorophenyl, 4-methoxyphenyl, pentafluorophenyl, p-hydroxyphenyl,
p-cyanophenyl, p-methanesulfonamidophenyl,
3,4-dichlorophenyl).

As preferable substituents, Y is CN, CF
₃ , COR ₂ and COOR ₂ , Z is a lower alkyl group having 5 or less carbon atoms, R ₁ and R ₂ are alkyl groups having 5 or more carbon atoms, and m is preferably an integer of 3 to 5.

[0014]

[Chemical 6]

In the formula, A represents an atomic group necessary for forming a condensed polycyclic carbocycle, and X and Y are NO ₂ , CN, CF ₃ and C.
OR ₂ , COOR ₂ , CONHR ₂ , halogen, SOR ₂ ,
Represents SO ₂ R ₂ or OCOR ₂ , Z represents an alkyl group, an aryl group, OR ₂ , OH or N (R ₂ ) ₂ , R ₁ represents an alkyl group, and R ₂ represents an alkyl group or an aryl group . l, m and n each represent 0 or a positive integer, l + m represents an integer of 2 or more, and m + n represents an integer of 2 to 8. The plural groups represented by X, Y, Z and R ₂ may be the same or different from each other.

When the substituent in the above general formula [II] is an alkyl group or contains an alkyl group, the alkyl group may be linear, branched or crosslinked unless otherwise specified. Cyclic ring, which may be substituted or may contain an unsaturated bond (eg, methyl, ethyl, iso-propyl, t-butyl, pentyl, 2-
Ethylhexyl, dodecyl, allyl, oleyl, benzyl, hydroxyethyl, methoxyethyl, phenoxyethyl, cyclopentyl, cyclohexyl, norbornyl).

When the substituent in the above general formula [II] is an aryl group or contains an aryl group, the aryl group may be substituted unless otherwise specified, and a monocyclic or condensed ring aryl group ( For example, phenyl, 1-naphthyl, p-tolyl, p-chlorophenyl, 4-methoxyphenyl, pentafluorophenyl, p-hydroxyphenyl,
p-cyanophenyl, p-methanesulfonamidophenyl,
3,4-dichlorophenyl) is meant.

The fused polycyclic carbocycle represented by A is
For example, naphthalene, anthracene, phenanthrene,
Examples include pyrene, naphthoquinone, and anthraquinone.

As preferable substituents, X and Y are CN,
CF ₃ , COR ₂ and COOR ₂ , Z is a lower alkyl group having 5 or less carbon atoms, R ₁ and R ₂ are alkyl groups having 5 or more carbon atoms, and preferable values of l, m and n are m is 3 From 5
Where l and n are 0 or 1, and l + m is an integer of 3 or more.

[0020]

[Chemical 7]

In the formula, B represents a hydrocarbon atom group necessary for forming an alicyclic carbon ring together with the carbon atom of the benzene ring, and X and Y are NO ₂ , CN, CF ₃ , COR ₂ and COO.
R ₂ , CONHR ₂ , halogen, SOR ₂ , SO ₂ R ₂ or OCOR ₂ is represented, and Z is an alkyl group, an aryl group, O
It represents R ₂ , OH or N (R ₂ ) ₂ , R ₁ represents an alkyl group, and R ₂ represents an alkyl group or an aryl group. l,
m and n each represent 0 or a positive integer, and l + m is 2
The above integers are represented, and m + n represents an integer of 2 to 8. The plural groups represented by X, Y, Z and R ₂ may be the same or different from each other.

When the substituent in the above general formula [III] is an alkyl group or contains an alkyl group, the alkyl group may be linear, branched or crosslinked unless otherwise specified. A cyclic ring, which may be substituted,
An alkyl group which may contain an unsaturated bond (for example,
Methyl, ethyl, iso-propyl, t-butyl, pentyl,
2-ethylhexyl, dodecyl, allyl, oleyl, benzyl, hydroxyethyl, methoxyethyl, phenoxyethyl, cyclopentyl, cyclohexyl, norbornyl).

When the substituent in the above general formula [III] is an aryl group or contains an aryl group, the aryl group may be substituted unless otherwise specified, and a monocyclic or condensed ring aryl group ( For example, phenyl, 1-naphthyl, p-tolyl, p-chlorophenyl, 4-methoxyphenyl, pentafluorophenyl, p-hydroxyphenyl, p-cyanophenyl, p-methanesulfonamidophenyl, 3,4-dichlorophenyl) To do.

The alicyclic ring represented by B is preferably a 5- or 6-membered carbon ring. As preferable substituents, X and Y are CN, CF ₃ , COR ₂ and COOR ₂ , Z is a lower alkyl group having 5 or less carbon atoms, R ₁ and R ₂ are alkyl groups having 5 or more carbon atoms, As preferable l, m, and n, m is an integer of 3 to 5, and l and n are 0 or 1.
And l + m is an integer of 3 or more.

[0025]

[Chemical 8]

In the formula, D represents a group of non-metal atoms necessary for forming a heterocyclic group, and X and Y are NO ₂ , CN, CF ₃ and CO.
R ₂ , COOR ₂ , CONHR ₂ , halogen, SOR ₂ , S
Represents O ₂ R or OCOR ₂ , Z represents an alkyl group, an aryl group, OR ₂ , OH or N (R ₂ ) ₂ , R ₁ represents an alkyl group, and R ₂ represents an alkyl group or an aryl group. l, m and n each represent 0 or a positive integer,
+ M represents an integer of 2 or more, and m + n represents an integer of 2 to 8. The plural groups represented by X, Y, Z and R ₂ may be the same or different from each other.

When the substituent in the above general formula [IV] is an alkyl group or contains an alkyl group, the alkyl group may be linear, branched or crosslinked unless otherwise specified. Cyclic ring, which may be substituted or may contain an unsaturated bond (eg, methyl, ethyl, iso-propyl, t-butyl, pentyl, 2-
Ethylhexyl, dodecyl, allyl, oleyl, benzyl, hydroxyethyl, methoxyethyl, phenoxyethyl, cyclopentyl, cyclohexyl, norbornyl).

When the substituent in the above general formula [IV] is an aryl group or includes an aryl group, the aryl group may be substituted unless otherwise specified, and a monocyclic or condensed ring aryl group ( For example, phenyl, 1-naphthyl, p-tolyl, p-chlorophenyl, 4-methoxyphenyl, pentafluorophenyl, p-hydroxyphenyl,
p-cyanophenyl, p-methanesulfonamidophenyl,
3,4-dichlorophenyl) is meant.

The heterocyclic group represented by D includes O, N,
It is a 3- to 8-membered optionally substituted monocyclic or condensed-ring heterocycle containing at least one heteroatom selected from S, P, Se, and Te, for example, succinimide, maleimide, phthalimide, Examples thereof include pyrrole, pyrazole, imidazole, selenazole, triazole, tetrazole, indole, pyridine, pyrimidine, morpholine, triazine, phosphazan, benzimidazole, benzthiazole, benzthiadiazole and imidazolopyrimidine.

The preferred heterocyclic group represented by D is
It is a 5- or 6-membered optionally substituted monocyclic ring or a 5- or 6-membered fused heterocycle containing at least one heteroatom selected from O, N and S in the ring.

As preferred substituents, X and Y are CN,
CF ₃ , COR ₂ and COOR ₂ , Z is a lower alkyl group having 5 or less carbon atoms, R ₁ and R ₂ are alkyl groups having 5 or more carbon atoms, and preferable values of l, m and n are m is 3 Is an integer from 0 to 5, 1 and n are 0 or 1, and l + m is an integer of 3 or more.

The high performance of the present invention as a charge transport material is
It seems that the long-term compatibility with the binder is kept stable as compared with the conventional charge transport material.

Next, specific examples of the compound represented by the above general formula and synthetic examples thereof will be shown.

(I) Compound represented by the general formula [I]: Exemplified compound:

[0035]

[Chemical 9]

[0036]

[Chemical 10]

[0037]

[Chemical 11]

[0038]

[Chemical 12]

: Synthesis example:

[0040]

[Chemical 13]

Exemplified Compound I-1 was synthesized according to the above synthetic route. Compound 3 was synthesized according to a known method (J. Chem, Soc, 1071 to 6 (1954)) using 2,4-bis (trifluoromethyl) bromobenzene 1 (manufactured by Aldrich) as a starting material.

10 g of Compound 3 was placed in a 100 ml four-headed flask, and 20 g of zinc chloride, 5 g of t-octylamine 4 (manufactured by Aldrich) and o-dichlorobenzene (hereinafter abbreviated as ODB).
100 ml was added, and the mixture was heated under reflux for 55 hours with an ester tube and a thermometer attached. After allowing to cool, the solid is removed by suction filtration and washed well with ethyl acetate. The solvent of the mother liquor was distilled off under reduced pressure, and the residue was applied to a silica gel column. Toluene: n-hexane =
The 1: 1 eluate was crystallized with n-hexane to obtain 7.9 g (yield 61%) of a red powder of Exemplified Compound I-1. The melting point was determined to be 171-173 ° C according to the Japanese Pharmacopoeia melting point measuring method. Since the elemental analysis values also agreed well with the calculated values, the structure of Exemplified Compound I-1 was confirmed.

C H N calculated value 58.18% 4.48% 2.83% measured value 57.97% 4.55% 2.78% (II) compound represented by general formula [II]: exemplified compound:

[0044]

[Chemical 14]

[0045]

[Chemical 15]

[0046]

[Chemical 16]

[0047]

[Chemical 17]

[0048]

[Chemical 18]

[0049]

[Chemical 19]

: Synthesis example:

[0051]

[Chemical 20]

Exemplified Compound II-1 was synthesized according to the above synthetic route. Compound 3 was synthesized according to a conventional method using 2,4-bis (trifluoromethyl) bromobenzene 1 (manufactured by Aldrich) as a starting material.

10 g of Compound 3 was placed in a 100 ml four-headed flask, 20 g of zinc chloride, 5 g of 9-aminophenanthrene 4 (manufactured by Aldrich Co.) and 100 ml of ODB were added, and an ester tube and a thermometer were attached and heated for 50 hours. Refluxed. After allowing to cool, the solid is removed by suction filtration and washed well with ethyl acetate. The solvent of the mother liquor was distilled off under reduced pressure, and the residue was applied to a silica gel column.
The toluene: n-hexane = 1: 1 eluate was crystallized from n-hexane to give 9.3 g (yield 64%) of Exemplified Compound II-1 dark red crystals. The melting point was 193-194 ° C. as measured by the Japanese Pharmacopoeia melting point measuring method. Since the elemental analysis values also agreed well with the calculated values, the structure of Exemplified Compound II-1 was confirmed.

CHN calculated value 64.41% 2.52% 2.50% measured value 64.32% 2.57% 2.45% (III) compound represented by general formula [III]: exemplified compound:

[0055]

[Chemical 21]

[0056]

[Chemical formula 22]

[0057]

[Chemical formula 23]

[0058]

[Chemical formula 24]

: Synthesis example:

[0060]

[Chemical 25]

Exemplified compound III-1 according to the above synthetic route
Was synthesized. 2,4-bis (trifluoromethyl) bromobenzene 1 (manufactured by Aldrich Co.) was used as a starting material according to a known method (J. Chem, Soc, 1071-6 (1954)) to give a compound.
3 was synthesized.

10 g of compound 3 was placed in a 100 ml four-headed flask, 20 g of zinc chloride, 5 g of 1-amino-5,6,7,8-tetrahydronaphthalene 4 (manufactured by Aldrich) and 100 ml of ODB were added, and the ester tube and temperature were adjusted. A meter was turned on and the mixture was heated under reflux for 50 hours. After cooling, the solid is removed by suction filtration and washed well with ethyl acetate and chloroform. The solvent of the mother liquor was distilled off under reduced pressure, and the residue was applied to a silica gel column. The toluene: n-hexane = 1: 1 eluate was crystallized from n-hexane to obtain 7.5 g (yield 55%) of a red powder of Exemplified Compound III-1.
Melting point was measured according to the Japanese Pharmacopoeia melting point measurement method 187-1
It was 88 ° C.

Since the elemental analysis values were in good agreement with the calculated values, the structure of Exemplified Compound III-1 was confirmed.

C H N calculated value 60.83% 3.14% 2.73% Actual value 60.68% 3.25% 2.70% (IV) Compound represented by general formula [IV]: Exemplified compound:

[0065]

[Chemical formula 26]

[0066]

[Chemical 27]

[0067]

[Chemical 28]

[0068]

[Chemical 29]

[0069]

[Chemical 30]

[0070]

[Chemical 31]

[0071]

[Chemical 32]

[0072]

[Chemical 33]

[0073]

[Chemical 34]

[0074]

[Chemical 35]

[0075]

[Chemical 36]

[0076]

[Chemical 37]

[0077]

[Chemical 38]

: Synthesis example:

[0079]

[Chemical Formula 39]

Exemplified Compound IV-1 was synthesized according to the above synthetic route. Using 2,4-bis (trifluoromethyl) bromobenzene 1 as a starting material, a known method (J. Chem, Soc, 10
71 to 6 (1954)), compound 3 was synthesized.

CompoundThree Put 10g into a 100ml four-headed flask
20 g of zinc chloride and 5-amino-1-ethylpyrazoleFour
Add 5g (made by Aldrich) and 100ml ODB,
A tellurium tube and a thermometer were attached, and the mixture was heated under reflux for 40 hours. After cooling
The solid is filtered off with suction and rinsed well with DMSO. Mother liquor
The solvent was distilled off under reduced pressure and the residue was applied to a silica gel column.
did. Toluene: n-hexane = 9: 1 eluate,
9.3 g of red crystal of Exemplified Compound IV-1
(Yield 75%) was obtained. Melting point is according to Japanese Pharmacopoeia Melting Point Measurement Method
The measurement result was 168 to 170 ° C. Calculate elemental analysis values
Since the values were in good agreement, the structure of Exemplified Compound IV-1 was
confirmed.

C H N calculated value 52.84% 2.53% 8.80% Measured value 52.81% 2.55% 8.77% In the electrophotographic photosensitive member of the present invention, examples of the conductive support include metal pipes, metal plates, metal sheets, and metal foils. ,
A conductive polymer film, a polymer film provided with a vapor deposition layer of a metal such as Al, a polymer film coated with a metal oxide, a quaternary ammonium salt, or the like, or paper is used.

In the electrophotographic photosensitive member of the present invention, the photosensitive layer is provided on the conductive support, but the photosensitive layer may have a single layer structure, or a laminated structure in which the charge generating layer and the charge transporting layer are functionally separated. It may be one. An adhesive layer may be provided between the conductive support and the photosensitive layer.

As shown in FIG. 1A, the photoconductor of the present invention comprises a charge generating layer (CGL) 2 containing a charge generating substance (CGM) as a main component and a charge transporting substance () on a conductive support 1. CT
A photosensitive layer 4 formed of a laminate with a charge transport layer (CTL) 3 containing M) as a main component is provided. As shown in FIG. 2B, the photosensitive layer 4 may be provided via the intermediate layer 5 provided on the conductive support 1. Thus, when the photosensitive layer 4 has a two-layer structure, a photoreceptor having the most excellent electrophotographic characteristics can be obtained. Further, in the present invention, FIG.
And a layer 6 containing the CTM as a main component as shown in (d).
A photosensitive layer 4 having fine particle-shaped CGM 7 dispersed therein may be provided directly on the conductive support 1 or via the intermediate layer 5.

Further, a protective layer (OCL) may be provided on the photosensitive layer 4 if necessary.

Further, CGL constituting the photosensitive layer 4 having a two-layer structure
2. The CTL 3 may be formed by the following method depending on the characteristics of CTM and CGM, directly or on the conductive support 1 which is the lower layer surface, or when an intermediate layer such as an adhesive layer or a barrier layer is provided if necessary. it can.

(1) Vapor deposition method (2) Coating method a) Method of coating a solution coating prepared by dissolving CGM and CTM in a suitable solvent.

B) A method in which CGM and CTM are made into fine particles in a dispersion medium by a ball mill, a homomixer or the like, and a dispersion liquid coating material obtained by mixing and dispersing with a binder as necessary is applied.

Examples of the vapor deposition method include a vacuum vapor deposition method, a sputtering method, an ion plating method or a CVD method, and a coating method includes a dipping method, a spray method, an air doctor method, a doctor blade method and a reverse method. An appropriate method is selected according to the physical properties of the coating material such as the roll method.

The adhesive layer is formed of resin alone, coated with a low resistance compound such as tin oxide, indium oxide or titanium oxide dispersed in resin, or coated with aluminum oxide, zinc oxide, silicon oxide or the like. The vapor deposition film of
The resin used for the adhesive layer is not particularly limited, and examples thereof include vinylidene chloride-vinyl chloride copolymer, water-soluble polyvinyl butyral resin, alcohol-soluble polyamide resin, vinyl acetate-based resin, polyvinyl alcohol, nitrocellulose, and polyimide resin. To be

The thickness of the binder layer is preferably about 0.01 to 10 μm, particularly preferably 0.01 to 1 μm.

When the photosensitive layer is a single layer, the compound represented by the above general formulas [I] to [IV] is contained as a sensitizer in the photosensitive layer composed of a known material such as polyvinylcarbazole. And those containing a compound represented by the above general formulas [I] to [IV] as an electron transporting substance in a photosensitive layer containing a known charge generating substance.

On the other hand, when the photosensitive layer is a laminated type,
The charge generation layer may be obtained by vapor deposition of a charge generation substance on a conductive support, or may be formed by applying a coating liquid containing a charge generation substance and a binder resin as main components. .

Any known charge generating substance and binder resin can be used. For example, as the charge generating substance, an inorganic semiconductor such as Te-Se, an organic semiconductor such as polyvinylcarbazole, a bisazo compound, a trisazo compound, a metal-free phthalocyanine compound, a metal phthalocyanine compound, a pyrylium compound, a squarylium compound, Organic pigments such as cyanine compounds, perylene compounds and polycyclic quinone compounds can be used. Among them, preferable charge generating substances include, for example, JP-A 64-170.
No. 66 Y-type titanyl phthalocyanine pigment having an X-ray diffraction peak at 27.2 °, JP-A No. 62-67094 A type titanyl phthalocyanine pigment having an X-ray diffraction peak at 26.3 °, JP-A No. 61-239248 B having a line diffraction peak at 28.7 °
Type titanyl phthalocyanine pigment, metal-free phthalocyanine pigment of JP-B-49-4338, copper phthalocyanine pigment of JP-A-57-163239, vanadyl phthalocyanine pigment of JP-A-57-148747, perylene of JP-A-49-128734. Pigments, condensed polycyclic pigments disclosed in JP-A-47-18544, and bisazo pigments disclosed in JP-A-1-150145. As the binder resin, polystyrene, silicone resin, polycarbonate resin, acrylic resin, methacrylic resin, polyester, vinyl polymer, cellulose resin, butyral resin, silicone modified butyral resin, alkyd resin and the like can be used.

The thickness of the charge generation layer is preferably about 0.01 to 10 μm, and particularly preferably 0.05 to 2 μm.

A charge transport layer is formed on the charge generation layer. The charge transport layer comprises a compound represented by the above general formulas [I] to [IV] and a binder resin,
A coating solution containing the compounds represented by the general formulas [I] to [IV], a binder resin, and a suitable solvent as a main component is coated on the charge generation layer by an applicator, a bar coater, a dip coater, or the like. Formed by. In this case, the mixing ratio of various compounds and the binder resin is preferably 1: 100 to 100: 1, and particularly preferably 1:20 to 20: 1.

As the charge transport material and the binder resin used in the charge transport layer, any known materials can be used. For example, as the binder resin, acrylonitrile-butadiene copolymer, styrene-butadiene copolymer, vinyltoluene-styrene copolymer, styrene-modified alkyd resin, silicone-modified alkyd resin, soybean oil-modified alkyd resin, vinylidene chloride-vinyl chloride Resin, polyvinyl butyral, nitrated polystyrene, polymethylstyrene, polyisoprene, polyester, phenol resin, Kent resin, polyamide, polycarbonate, polythiocarbonate, polyacrylate, polyhaloacrylate, vinyl acetate resin, polystyrene,
Examples thereof include polyallyl ether, polyvinyl acrylate, polysulfone and polymethacrylate. Among them, biphenyl Z type polycarbonate is particularly preferable. or,
An ambipolar photoreceptor may be prepared by adding an electron donating substance to the charge transport layer.

Further, an antioxidant or a radical trap agent may be added to the charge transport layer.

The thickness of the charge transport layer is preferably 2 to 100 μm, particularly preferably 5 to 50 μm.

In the electrophotographic photosensitive member of the present invention,
A barrier layer may be provided on the conductive support. The barrier layer is
It is effective in preventing the injection of unnecessary charges from the conductive support and has the effect of improving the image quality. Materials for forming the barrier layer include metal oxide such as aluminum oxide, acrylic resin, phenol resin, polyester resin, polyurethane and the like. The barrier layer may be provided on the adhesive layer or may be provided on the upper side.

[0101]

EXAMPLES Next, the present invention will be specifically described by way of examples.

In the examples described below, the compounds of the formulas [I] to [IV] according to the present invention will be described in each of Examples I to
The groups are classified into IV groups, and each group is; sensitivity evaluation (evaluation 1) ... Examples 1 to 10 and comparative example (1) Durability evaluation (evaluation 2) ... Examples 11 to 20 and comparative example (2) Image quality evaluation (evaluation 3) ... Comprised of Examples 21 to 30 and Comparative Example (3), except that each group is different in the compound according to the present invention.
The samples of Examples and Comparative Examples having exactly the same shape, the same kind, and the same size are assembled. The comparative examples of each group are the same for each evaluation.

Evaluation of Sensitivity Evaluation 1 Electrostatic copying paper test apparatus EPA-8100 for electrophotographic photoreceptor samples obtained in Example 1 and Comparative Example (1).
(Kawaguchi Electric Co., Ltd.) is used to charge to + 800V and 10 lu
The white light of x was exposed, and the exposure amount until the surface potential was halved was determined and used as the sensitivity. The results are shown in Tables 1 to 4.

Examples 1 to 10 A 0.5 μm-thick intermediate layer made of polyamide resin “CM8000” (manufactured by Toray Industries, Inc.) was provided on a PET film on which aluminum was vapor-deposited, and a perylene pigment CGM-shown below was provided thereon.
l 1 part, polyvinyl butyral resin "ESREC BM
S "(manufactured by Sekisui Chemical Co., Ltd.) and 50 parts of methyl ethyl ketone as a dispersion medium dispersed in a sand mill were applied using a wire bar to form a charge generation layer having a thickness of 0.3 μm. Then, 1 part of the exemplified compound shown in each of Tables 1 to 4 and 1.5 parts of a polycarbonate resin "Iupilon Z-200" (manufactured by Mitsubishi Gas Chemical Co., Inc.) are dissolved in 10 parts of THF, and blade-coated on the charge generation layer to give a film thickness of 20 μm. Was formed on the charge transport layer.

Comparative Example (1) Instead of the exemplified compound, the following comparative compound CTM (1)
Comparative samples were prepared in the same manner as in Example 1 except that was used.

Durability Evaluation Evaluation 2 The electrophotographic photoreceptor samples obtained in Example 11 and Comparative Example (2) were subjected to the following actual measurements with a U-1017 remodeling machine manufactured by Konica Corp. at the initial stage and after copying 10,000 sheets. The value was evaluated. The results are shown in Tables 1 to 4.

Vb: Black part potential, Vw: White part potential,
Vr: Residual potential Examples 11 to 20 A 0.5 μm-thick intermediate layer made of polyamide resin “X-1874M” (manufactured by Daicel Hüls) was provided on a PET film on which aluminum was vapor-deposited, and the pigment X type was not formed thereon. Metal phthalocyanine (manufactured by Dainippon Ink and Chemicals, Inc.) 1 part, polyvinyl butyral resin "ESREC BX-1" (manufactured by Sekisui Chemical Co., Ltd.) 0.4 part, methyl isopropyl ketone 50 as a dispersion medium
The liquid in which the parts were dispersed using a sand mill was applied using a wire bar to form a charge generation layer having a thickness of 0.3 μm. Then, 1 part of each of the (II) exemplified compounds in Tables 1 to 7 and a polycarbonate resin "Iupilon Z-200" (manufactured by Mitsubishi Gas Chemical Co., Inc.) 1.5
Part was dissolved in 10 parts of THF and blade-coated on the charge generation layer to form a charge transport layer having a thickness of 20 μm.

Comparative Example (2) Instead of the exemplified compound, the following comparative compound CTM (2)
Comparative samples were prepared in the same manner as in Example 11 except that was used.

Image Quality Evaluation Evaluation 3 The electrophotographic photosensitive member samples obtained in Example 21 and Comparative Example (3) were applied to a digital copy “Konica 9028” remodeling machine (charge polarity: positive, reverse development) manufactured by Konica Corporation. I made an image. These samples were then placed at low temperature (10
(° C.) environment was left for 1 month, and then images were reproduced again under the same conditions. The black spots on the white background portion of these copied images were evaluated. The results are shown in Tables 1 to 4.

To evaluate the black spots, the size and number of the black spots were measured using an image analyzer "Omnicon 300 type" (manufactured by Shimadzu Corp.).
This was done by determining how many were present per cm ² . The criteria for evaluating the black spots are as shown below. It should be noted that if the result of the black spot determination is ⊚ or ◯, it is practical, but if it is Δ, it is not suitable for practical use, and if it is ×, it is not suitable for practical use.

Number of black spots of φ0.05 mm or more (pieces / cm ² ) Black spot determination 0 ◎ 1-3 ○ 4-10 △ 11 or more × Examples 21-30 Polyamide resin “CM8000” on a cylindrical aluminum substrate (Manufactured by Toray Industries, Inc.), an intermediate layer having a thickness of 0.5 μm is provided, and a Bragg angle 2θ of 9.5 °, 24.1 ° and 27.
A liquid in which 1 part of titanyl phthalocyanine having a peak at 2 ° and 0.5 part of silicone-butyral resin and 50 parts of methyl isopropyl ketone as a dispersion medium were dispersed using a sand mill was dip-coated to form a charge generation layer having a thickness of 0.3 μm. Then, 1 part of the exemplified compound shown in each of Tables 1 to 4 and 1.5 parts of a polycarbonate resin "Iupilon Z-200" (manufactured by Mitsubishi Gas Chemical Co., Inc.) are dissolved in 10 parts of THF, and a dip coating is applied on the charge generation layer to form a film thickness of 20 μm. Was formed on the charge transport layer.

Comparative Example (3) Instead of the exemplified compound, the comparative compound CTM shown below
A comparative sample was prepared in the same manner as in Example 21 except that (3) was used.

[0113]

[Chemical 40]

[0114]

[Table 1]

[0115]

[Table 2]

[0116]

[Table 3]

[0117]

[Table 4]

As is clear from the above-mentioned tables, the electrophotographic photosensitive member using the charge transporting material of the present invention has higher sensitivity and repeatability than the electrophotographic photosensitive member using the conventional charge transporting material. The characteristics of the photoconductor during use are stable, and
It can be seen that the occurrence of image defects is extremely small even after storage at low temperature.

[0119]

The compound of the present invention has an electron transporting ability and is practical, that is, high sensitivity, low residual potential, good image retention,
A positive charging photoreceptor can be provided.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of an exemplary embodiment of a photoconductor of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Conductive support 2 Charge generation layer 3 Charge transport layer 4 Photosensitive layer 5 Intermediate layer 6 Layer containing charge transport substance 7 Charge generation substance

Claims (4)

[Claims] 1. An electrophotographic photoreceptor having a photosensitive layer provided on a conductive support, wherein the photosensitive layer contains a compound represented by the following general formula [I]. . [Chemical 1] [In the formula, Y is NO ₂ , CN, CF ₃ , COR ₂ , COO
R ₂ , CONHR ₂ , halogen, SOR ₂ , SO ₂ R ₂ or OCOR ₂ is represented, and Z is an alkyl group, an aryl group, O
It represents R ₂ , OH or N (R ₂ ) ₂ , R ₁ represents an alkyl group, and R ₂ represents an alkyl group or an aryl group. m represents an integer of 2 or more, n represents 0 or a positive integer, m
And the sum of n represents an integer of 2 to 8. There are multiple Y, Z,
The groups represented by R ₂ may be the same or different from each other. ] 2. An electrophotographic photoreceptor having a photosensitive layer provided on a conductive support, wherein the photosensitive layer contains a compound represented by the following general formula [II]. . [Chemical 2] [In the formula, A represents an atomic group necessary for forming a condensed polycyclic carbocycle, and X and Y are NO ₂ , CN, CF ₃ , COR ₂ , and C.
OOR ₂ , CONHR ₂ , halogen, SOR ₂ , SO ₂ R ₂
Or OCOR ₂ , Z represents an alkyl group, an aryl group, OR ₂ , OH or N (R ₂ ) ₂ , R ₁ represents an alkyl group, and R ₂ represents an alkyl group or an aryl group. l, m and n each represent 0 or a positive integer,
+ M represents an integer of 2 or more, and m + n represents an integer of 2 to 8. The plural groups represented by X, Y, Z and R ₂ may be the same or different from each other. ] 3. The electrophotographic photosensitive member according to claim 2, wherein the compound represented by the general formula [II] is a compound represented by the following general formula [III]. [Chemical 3] [In the formula, B represents a hydrocarbon atom group necessary to form an alicyclic carbon ring together with a carbon atom of a benzene ring, and X and Y represent NO ₂ , CN, CF ₃ , COR ₂ , COOR ₂ , CONHR.
₂ , halogen, SOR ₂ , SO ₂ R ₂ or OCOR ₂ , Z is an alkyl group, an aryl group, OR ₂ , OH or N (R ₂ ) ₂ , R ₁ is an alkyl group, R ₂ is Represents an alkyl group or an aryl group. l, m and n each represent 0 or a positive integer, l + m represents an integer of 2 or more, and m + n represents an integer of 2 to 8. There are multiple X,
The groups represented by Y, Z and R ₂ may be the same or different from each other. ] 4. An electrophotographic photoreceptor having a photosensitive layer provided on a conductive support, wherein the photosensitive layer contains a compound represented by the following general formula [IV]. . [Chemical 4] [In the formula, D represents a group of non-metal atoms necessary for forming a heterocyclic group, and X and Y are NO ₂ , CN, CF ₃ , COR ₂ , and CO.
Represents OR ₂ , CONHR ₂ , halogen, SOR ₂ , SO ₂ R ₂ or OCOR ₂ , Z is an alkyl group, an aryl group,
It represents OR ₂ , OH or N (R ₂ ) ₂ , R ₁ represents an alkyl group, and R ₂ represents an alkyl group or an aryl group. l,
m and n each represent 0 or a positive integer, and l + m is 2
The above integers are represented, and m + n represents an integer of 2 to 8. The plural groups represented by X, Y, Z and R ₂ may be the same or different from each other. ]