JPH0731406B2 - Electrophotographic photoconductor - Google Patents

Description

TECHNICAL FIELD The present invention relates to a photoconductor for electrophotography, and more specifically,
The present invention relates to an electrophotographic photoreceptor provided with a photosensitive layer containing a bisazo pigment as a substance that generates a charge carrier when irradiated with light (hereinafter referred to as "charge generating substance").

2. Description of the Related Art As an electrophotographic photoconductor, an inorganic photoconductor using selenium and its alloy, a photoconductor in which dye-sensitized zinc oxide is dispersed in a binder resin, or an organic photoconductor is used. Typical examples include those using a charge transfer complex of 2,4,7-trinitro-9-fluorenone (hereinafter referred to as “TNF”) and poly-N-vinylcarbazole (hereinafter referred to as “PVK”). ing.

However, these photoreceptors have many advantages and, at the same time, have various drawbacks. For example, selenium photoconductors that are widely used at present have difficult manufacturing conditions, are expensive to manufacture, are difficult to process into a belt because they are not flexible, and are sensitive to heat and mechanical shock. Therefore, be careful when handling. Zinc oxide photoconductor can be manufactured by applying it to a support using inexpensive zinc oxide, but the cost is low, but generally sensitivity is low, surface smoothness, hardness, tensile strength, and abrasion resistance are low. Since it has mechanical defects such as properties, it is often problematic in terms of durability as a photoreceptor for a plain paper copying machine that is repeatedly used. Further, a photoconductor using a charge transfer complex of TNF and PVK has low sensitivity and is not suitable as a photoconductor for a high speed copying machine.

In recent years, extensive research has been conducted in order to eliminate the drawbacks of these photoconductors, and in particular, various organic photoconductors have been proposed. Above all, a laminated type photoreceptor in which a thin film of an organic pigment is formed on a conductive support (charge generation layer) and a layer (charge transfer layer) mainly containing a charge transfer substance is formed on the conductive support is a conventional organic material type. Compared with the photoconductor of No. 1), it is generally noted as a photoconductor for a plain paper copying machine because of its high sensitivity and stable charging property, and some of them have been put to practical use.

This type of conventional laminated-type photoconductor uses (1) a thin layer obtained by vacuum-depositing a perylene derivative as a charge generation layer and an oxadiazole derivative as a charge transport layer (see usp 3871882) (2) It is known that a thin layer formed by coating an organic amine solution of chlordian blue is used as the charge generation layer and a hydrazone compound is used as the charge transport layer (see Japanese Patent Publication No. 55-42380).

However, it is also true that the conventional type of laminated type photoconductor has many advantages as well as various drawbacks. That is, it has the following drawbacks.

The photoreceptor using the perylene derivative and the oxadiazole derivative shown in (1) has a high manufacturing cost because the charge generation layer is formed by vacuum deposition.

The photoreceptor using the chlordyan blue and the hydrazone compound shown in (2) needs to use an organic amine (for example, ethylenediamine), which is generally difficult to handle, as a coating solvent for forming the charge generation layer. There are many downsides.

OBJECT The object of the present invention is to provide an electrophotographic photoreceptor which is easy to process and manufacture, has excellent thermal and mechanical strength, and is highly sensitive and inexpensive.

Structure The electrophotographic photoreceptor of the present invention is characterized in that a photosensitive layer containing a bisazo pigment represented by the following general formula (I) as a charge generating substance is provided on a conductive support.

(However, A represents a Kuppler residue, R may be the same or different, and a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted aryl group, benzoyl Group, a cyano group, a substituted amino group, a nitro group, an acetyl group, or a carboxyl group or an ester thereof, and n represents an integer of 1 to 4.) As the Kupler residue A in the general formula (I), there are phenols. , Naphthols, aminonaphthols, and aromatic hydrocarbon compounds having a hydroxyl group and / or an amino group;
A heterocyclic compound having a hydroxyl group and / or an amino group; a compound having an aliphatic or aromatic enolic ketone group,
That is, a residue such as a compound having an active methylene group can be mentioned, and specific examples include those represented by the following general formulas (II) to (XII).

{In the above formulas (II), (III), (IV) and (V), X, Y
₁ , Z, m and n represent the following, respectively.

x: -OH, Or —NHSO ₂ —R ₃ (R ₁ and R ₂ represent hydrogen or a substituted or unsubstituted alkyl group, and R ₃ represents a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group.) Y ₁ : Hydrogen, halogen, substituted or unsubstituted alkyl group, substituted or unsubstituted alkoxy group, carboxy group, sulfo group, substituted or unsubstituted sulfamoyl group or [R ₄ represents hydrogen, an alkyl group or a substituted product thereof, a phenyl group or a substituted product thereof, and Y ₂ is a hydrocarbon ring group or a substituted product thereof, a heterocyclic group or a substituted product thereof, or (However, R ₅ represents a hydrocarbon ring group or a substituted product thereof, a heterocyclic group or a substituted product thereof, or a styryl group or a substituted product thereof, R ₆ represents hydrogen, an alkyl group, a phenyl group or a substituted product thereof, or ₅ and R ₆ may form a ring together with the carbon atom bonded to them. ] Z: hydrocarbon ring or a substituted product thereof or a heterocyclic ring or a substituted product thereof, n: 1 or an integer of 2 m: 1 or an integer of 2} (In the formulas (VI) and (VII), R ₇ represents a substituted or unsubstituted hydrocarbon group, and X has the same meaning as described above.) (In the formula, R ₅ represents an alkyl group, a carbamoyl group, a carboxyl group or an ester thereof, Ar ₁ represents a hydrocarbon ring group or a substituted product thereof, and X is the same as the above.) (In the above formulas (IX) and (X), R ₉ represents hydrogen or a substituted or unsubstituted hydrocarbon group, and Ar ₂ represents a hydrocarbon ring group or a substituted product thereof.) The general formula (II), Z in (III), (IV) or (V)
Examples of the hydrocarbon ring include a benzene ring and a naphthalene ring, and examples of the heterocycle include an indole ring, a carbazole ring, and a benzofuran ring. Examples of the substituent on the ring of Z include a halogen atom such as a chlorine atom and a bromine atom, and an alkoxy group.

The hydrocarbon ring group for Y ₂ or R ₅ is a phenyl group, a naphthyl group, an anthryl group, a pyrenyl group, or the like, and the heterocyclic group is a pyridyl group, a thienyl group, a furyl group, an indolyl group, a benzofuranyl group, or a carbazolyl group. Group, a dibenzofuranyl group, and the like, and examples of the ring formed by combining R ₅ and R ₆ include a fluorene ring and the like.

Examples of the substituent on the hydrocarbon ring group or heterocyclic group of Y ₂ or R ₅ or the ring formed by R ₅ and R ₆ include
Alkyl groups such as methyl group, ethyl group, propyl group, butyl group, alkoxy groups such as methoxy group, ethoxy group, propoxy group, butoxy group, halogen atoms such as chlorine atom, bromine atom, dimethylamino group, diethylamino group, etc. Dialkylamino group, diaralkylamino group such as dibenzylamino group, halomethyl group such as trifluoromethyl group, nitro group, cyano group, carboxyl group or ester thereof, hydroxyl group, sulfonate group such as -SO ₃ Na, etc. To be

A halogen atom such as a chlorine atom or a bromine atom can be exemplified as the substituent of the phenyl group of R ₄ .

Typical examples of the hydrocarbon group for R ₇ or R ₉ include an alkyl group such as a methyl group, an ethyl group, a propyl group, and a butyl group, an aralkyl group such as a benzyl group, an aryl group such as a phenyl group, or a substituent thereof. It can be illustrated.

As the substituent in the hydrocarbon group of R ₇ or R ₉ , a methyl group, an ethyl group, a propyl group, an alkyl group such as a butyl group, a methoxy group, an ethoxy group, a propoxy group, an alkoxy group such as a butoxy group, a chlorine atom, Examples include halogen atoms such as bromine atom, hydroxyl group, and nitro group.

Representative examples of the hydrocarbon ring group in Ar ₁ or Ar ₂ include a phenyl group and a naphthyl group, and the substituents in these groups include a methyl group, an ethyl group, a propyl group, a butyl group and the like. Examples thereof include alkyl groups, methoxy groups, ethoxy groups, propoxy groups, butoxy groups and other alkoxy groups, nitro groups, halogen atoms such as chlorine and bromine atoms, cyano groups, dimethylamino groups, and dialkylamino groups such as diethylamino groups. .

Further, in X, a hydroxyl group is particularly suitable.

Among the above-mentioned Kupler residues, preferred are those represented by the above general formulas (III), (VI), (VII), (VIII), (IX) and (X), in which X in the general formula is a hydroxyl group. Are preferred. Among these, the general formula (XI) (Y ₁ and Z are the same as above), and a Kuppler residue represented by the above is more preferable, and a general formula (VII) is more preferable. (Z, Y ₂ and R ₂ are the same as above).

Furthermore, among the above-mentioned preferred Kupler residues, the compound represented by the general formula (VIII) or (XIV) (Z, R ₂ , R ₅ and R ₆ are the same as described above, and R ₁₀ is preferably the above-mentioned substituent of Y _2. )

Specific examples of the bisazo pigment used in the present invention as described above are shown by the structural formulas as follows.

The bisazo pigment of the general formula (I) used in the present invention is represented by the following reaction formula: first, 2,7-dinitro-9,10-phenanthrenequinone of the formula (XV) and ortho of the formula (XVI). A diphenyl derivative of phenazine represented by the general formula (XVII) is dehydrated and condensed with a phenylenediamine derivative (wherein R is the same as R in the general formula (I)), and the dinitro derivative is reduced to give the general formula (XVIII). ), And then diazotizing this compound to form a diazonium salt compound represented by the general formula (XIX) (wherein Y is an anion functional group), which is further treated as N, N-dimethylformamide (DMF). It can be easily produced by a coupling reaction with a coupler represented by the formula AH (A is the same as A in the general formula (I)) in a simple organic solvent. As an example, a production example of the bisazo pigment of No. 1 will be shown below, but other bisazo pigments can be easily produced according to this production example except that the cuppler is changed.

Production Example 2,7-Dinitro-9,10-phenanthrenequinone 3.60 g (0.01
21 mol) and orthophenylenediamine 1.96 g (0.0181
1 mol of piperidine and 20 parts of ortho-dichlorobenzene
0 ml was added and the mixture was heated under reflux for 10 minutes. After cooling, the precipitated crystals were collected, washed with 100 ml of methanol and dried to obtain 4.36 g of yellow crystals. This was recrystallized from about 400 ml of orthodichlorobenzene to obtain 3.44 g (yield 76.8%) of a purified product (yellow needle crystals). The melting point of this product was 300 ° C. or higher, and the elemental analysis values were as follows. From these data, it was confirmed that this crystal was a dinitro compound of the general formula (XVII) in which R ₁ = H, n = 1.

Elemental analysis value: Calculated value Actual value C% 64.86 65.00 H% 2.72 2.74 N% 15.13 15.04 Next, 2.65 g (7.16 × 10 ^-3 mol) of this dinitro compound was added to 35%.
% Hydrochloric acid aqueous solution 70ml, SnCl ₂ · 2H ₂ O 12.2g (0.5029
(Mol) was added, and the mixture was stirred at about 80 ° C. for 1 hour for reaction. After cooling, the precipitate obtained was removed and the precipitate was washed with water.
250 ml was added, and sodium hydroxide was further added until it became strongly alkaline, and after stirring sufficiently, the precipitate was taken again,
After washing with water, it was dried to obtain 2.22 g of black-purple crystals. This was recrystallized with a mixed solvent consisting of about 100 ml of ortho-dichlorobenzene and about 100 ml of nitrobenzene to obtain 1.90 g of a purified product (black purple needle crystals). This product had a melting point of 300 ° C. or higher and the elemental analysis values were as follows. From these data, this crystal shows that in the general formula (XVIII), R ₁ = H, n
It was confirmed that the diamino compound was = 1.

Elemental analysis value: Calculated value Actual value C% 77.40 76.95 H% 4.55 4.48 N% 18.05 17.74 Next, 1.58 g (5.09 × 10 ⁻³ mol) of this diamino compound was added to 1 part of water.
After adding 00 ml and 100 ml of 20% hydrochloric acid aqueous solution with stirring for 30 minutes at room temperature, 0.74 g of sodium nitrite (purity 97%) was dissolved in 5 ml of water while cooling the solution to 2-3 ° C. The resulting solution was added dropwise over 2 minutes to react. Then, after stirring for 30 minutes at the above temperature, the reaction solution is passed,
12 ml of 42% aqueous solution of borofluoric acid was added to the solution, and the precipitated crystals were collected, washed with methanol and dried to obtain 2.38 g of yellow crystals. This is the infrared absorption spectrum (KB
The absorption based on the diazonium group was observed at 2300 cm ^-1 in the (r tablet method). Therefore, in the general formula (XIX), R ₁ = H, n
It was confirmed that the compound was a diazonium salt compound with = 1 and Y = BF ₄ .

Next, 1.27 g (0.0025 mol) of this diazonium salt compound and 1.32 g (0.005 mol) of 2-hydroxy-3-naphthoic acid anilide as a cuplar were dissolved in 250 ml of cooled DMF,
8 ml of a 10.5% sodium acetate aqueous solution was added dropwise thereto at a temperature of 5 to 10 ° C over 5 minutes, and then stirred at room temperature for 2 hours to carry out a coupling reaction. Remove the formed precipitate,
It was washed 3 times with 200 ml of DMF heated to 80 ° C, then twice with 200 ml of water, and then dried under reduced pressure at a temperature of 120 ° C to give a purple-red powder.
1.28 g (yield 59.6%) was obtained. The melting point of this product was 300 ° C. or higher, and the elemental analysis values were as follows.

Elemental analysis value: Calculated value Actual value C% 75.51 75.22 H% 3.99 3.76 N% 13.05 12.73 From these data and infrared absorption spectrum (KBr method) measured separately, this powder was identified as the bisazo compound of Compound No. 1. confirmed.

In the electrophotographic photoreceptor of the present invention, the bisazo pigment is used as a charge generating substance in the photosensitive layer, and a typical constitution of this photoreceptor is shown in FIGS. 1 and 2.

The photoconductor of FIG. 1 has a bisazo pigment on a conductive support 11.
A laminate type photosensitive layer 191 including a charge generation layer 15 mainly composed of 13 and a charge transport layer 17 mainly composed of a charge carrier substance is provided.

In the photoconductor of FIG. 1, the imagewise exposed light passes through the charge transport layer and reaches the charge generation layer 15, where the bisazo pigment is present.
On the other hand, the charge is generated at 13, while the charge transport layer 17 receives and injects the charge, and the bisazo pigment 13 generates the charge necessary for light attenuation, and the charge transport is performed by the charge transport. It is a mechanism called in layer 17.

The photoreceptor shown in FIG. 2 has a photosensitive layer 192 mainly composed of a bisazo pigment 13, a charge carrier substance and an insulating binder on a conductive support 11. Again, the bisazo pigment 13 is a charge generating substance.

As another photosensitive member, the charge generation layer and the charge transport layer shown in FIG. 1 can be reversed.

The thickness of the photosensitive layer is as shown in FIG. 1, and the thickness of the charge generation layer 15 is preferably 0.01 to 5 μ, more preferably 0.05 to 2 μ. If this thickness is 0.01 μm or less, the generation of electric charges is not sufficient, and if it is 5 μm or more, the residual potential is high and it cannot be put to practical use. The thickness of the charge transport layer 17 is preferably 3 to 50 μ, more preferably 5 to 20 μ. If this thickness is 3 μm or less, the charge amount is insufficient, and if it is 50 μm or more, the residual potential is high and it is not practical.

The charge generation layer 15 is mainly composed of the bisazo pigment represented by the above general formula, and may further contain a binder, a plasticizer and the like. The proportion of the bisazo pigment in the charge generation layer is preferably 30% by weight or more, more preferably 50% by weight or more.

The charge transport layer 17 is mainly composed of a charge transport material and a binder, and may further contain a plasticizer and the like. The proportion of the charge carrier material in the charge carrier layer is 10 to 95% by weight, preferably 30 to 90%.
% By weight. If the proportion of the charge carrier material is less than 10% by weight, the charge carrier is hardly transferred, and
If it is more than 5% by weight, the mechanical strength of the photoreceptor film is extremely poor and it cannot be put to practical use.

In the case of the photoreceptor shown in FIG. 2, the thickness of the photosensitive layer 192 is preferably 3 to 50 μ, more preferably 5 to 20 μ.
The ratio of the bisazo pigment in the photosensitive layer 192 is preferably 5
0 wt% or less, more preferably 20 wt% or less,
The proportion of the charge carrier substance is preferably 10 to 95% by weight, more preferably 30 to 90% by weight.

The present invention is characterized in that a specific bisazo pigment represented by the general formula (I) is used as a charge generating substance in an electrophotographic photoreceptor, and a conductive support,
As the other components such as the charge carrier substance, any of those conventionally known can be used, which will be specifically described below.

As the conductive support used in the photoreceptor of the present invention, aluminum, copper, a metal plate such as zinc, a plastic sheet such as polyester or a plastic film aluminum, a conductive material such as SnO ₂ is vapor-deposited, or conductive. Treated paper is used.

Examples of the binder include condensation resins such as polyamide, polyurethane, polyester, epoxy resin, polyketone, and polycarbonate, and vinyl polymers such as polyvinyl ketone, polystyrene, poly-N-vinylcarbazole, and polyacrylamide. Any adhesive and adhesive resin can be used.

Examples of the plasticizer include halogenated paraffin, polychlorinated biphenyls, dimethylnaphthalene, dibutyl phthalate and the like. In addition, silicone oil or the like may be added to improve the surface property of the photoreceptor.

The charge carrier material includes a hole carrier material and an electron carrier material.
As the hole-transporting substance, for example, the following general formula (1) to
Examples thereof include the compounds shown in (11).

[In the formula, R ₁₁₅ represents a methyl group, an ethyl group, a 2-hydroxyethyl group or a 2-chloroethyl group, and R ₁₂₅ represents a methyl group,
It represents an ethyl group, a benzyl group or a phenyl group, and R ₁₃₅ represents hydrogen, chlorine, bromine, an alkyl group having 1 to 4 carbon atoms, an alkoxyl group having 1 to 4 carbon atoms, a dialkylamino group or a nitro group. ] [In the formula, Ar ₃ represents a naphthalene ring, an anthracene ring, a styryl group and a substitution product thereof, or a pyridine ring, a furan ring, and a thiophene ring, and R ₁₄₅ represents an alkyl group or a benzyl group. ] [In the formula, R ₁₅₅ is an alkyl group, a benzyl group, a phenyl group,
Represents a naphthyl group, R ₁₆₅ represents hydrogen, an alkyl group having 1 to 3 carbon atoms, an alkoxy group having 1 to 3 carbon atoms, a dialkylamino group, a diaralkylamino group or a diarylamino group, and n is an integer of 1 to 4. When n is 2 or more, R ₁₆₅ may be the same or different. R ₁₇₅ represents hydrogen or a methoxy group. ] [In the formula, R ₁₈₅ represents an alkyl group having 1 to 11 carbon atoms, a substituted or unsubstituted phenyl group or a heterocyclic group, and R ₁₉₅ , R
₂₀₅ may be the same or different and each represents hydrogen, an alkyl group having 1 to 4 carbon atoms, a hydroxyalkyl group, a chloroalkyl group, a substituted or unsubstituted aralkyl group, or R ₁₉₅ and R ₂₀₅ are the same as each other. It may combine with each other to form a heterocycle containing nitrogen. R ₂₁₅ may be the same or different and represent hydrogen, an alkyl group having 1 to 4 carbon atoms, an alkoxy group or halogen. ] [In the formula, R ₂₂₅ represents hydrogen or a halogen atom, and Ar ₄
Represents a substituted or unsubstituted phenyl group, naphthyl group, anthryl group or carbazolyl group. ] [In the formula, R ₂₃₅ is hydrogen, halogen, a cyano group, or a carbon number of 1 to 1.
4 represents an alkoxy group having 4 or an alkyl group having 1 to 4 carbon atoms, and Ar ₅ is R ₂₄₅ represents an alkyl group having 1 to 4 carbon atoms,
R ₂₅₅ represents hydrogen, halogen, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, or a dialkylamino group, n is 1 or 2, and when n is 2, R ₂₅₅
May be the same or different, and R ₂₆₅ and R ₂₇₅ represent hydrogen, a substituted or unsubstituted alkyl group having 1 to 4 carbon atoms, or a substituted or unsubstituted benzyl group. ] [In the formula, R ₂₈₅ and R ₂₉₅ are a carbazolyl group, a pyridyl group,
A thienyl group, an indolyl group, a furyl group, or a substituted or unsubstituted phenyl group, a styryl group, a naphthyl group or an anthryl group, wherein these substituents are a dialkylamino group, an alkyl group, an alkoxy group, a carboxy group or an ester thereof. Represents a group selected from the group consisting of a halogen atom, a cyano group, an aralkylamino group, an N-alkyl-Naralkylamino group, an amino group, a nitro group and an acetylamino group. ] [In the formula, R ₃₀₅ represents a lower alkyl group or a benzyl group, and R ₃₁₅ represents a hydrogen atom, a lower alkyl group, a lower alkoxy group, a halogen atom, a nitro group, an amino group, or an amino substituted with a lower alkyl group or a benzyl group. Represents a group, and n represents an integer of 1 or 2. ] (In the formula, R ₃₂₅ represents a hydrogen atom, an alkyl group, an alkoxy group or a halogen atom, R ₃₃₅ and R ₃₄₅ represent an alkyl group, a substituted or unsubstituted aralkyl group or a substituted or unsubstituted aryl group, and R ₃₅₅ Represents a hydrogen atom or a substituted or unsubstituted phenyl group, and Ar ₆
Represents a phenyl group or a naphthyl group. ] [In the formula, n is an integer of 0 or 1, R ₃₆₅ represents a hydrogen atom, an alkyl group or a substituted or unsubstituted phenyl group,
A ₁ is Represents a 9-anthryl group or a substituted or unsubstituted N-alkylcarbazolyl group, wherein R ₃₇₅ represents a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom or (Wherein R ₃₈₅ and R ₃₉₅ represent an alkyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aryl group, and R ₃₈₅ and R ₃₉₅ may form a ring),
m is an integer of 0, 1, 2 or 3, and when m is 2 or more, R ₃₇₅ may be the same or different. ] [In the formula, R ₄₀₅ , R ₄₁₅ and R ₄₂₅ represent hydrogen, a lower alkyl group, a lower alkoxy group, a dialkylamino group or a halogen atom, and n represents 0 or 1. Examples of the compound represented by the general formula (1) include 9-ethylcarbazole-3-aldehyde, 1-methyl-1-phenylhydrazone, 9-ethylcarbazole-3-aldehyde 1-benzyl-1-phenylhydrazone. , 9-ethylcarbazole-3-aldehyde 1,1-diphenylhydrazone.

Examples of the compound represented by the general formula (2) include 4-diethylaminostyrene-β-aldehyde 1-methyl-1-phenylhydrazone and 4-methoxynaphthalene-1-aldehyde.
Examples include 1-benzyl-1-phenylhydrazone.

Examples of the compound represented by the general formula (3) include 4-methoxybenzaldehyde 1-methyl-1-phenylhydrazone, 2,4-dimethoxybenzaldehyde 1-benzyl-1-phenylhydrazone, 4-diethylaminobenzaldehyde.
1,1-diphenylhydrazone, 4-methoxybenzaldehyde 1-benzyl-1- (4-methoxy) phenylhydrazone,
Examples include 4-diphenylaminobenzaldehyde 1-benzyl-1-phenylhydrazone and 4-dibenzylaminobenzaldehyde-1,1-diphenylhydrazone.

Examples of the compound represented by the general formula (4) include 1,1-bis (4-dibenzylaminophenyl) propane, tris (4-diethylaminophenyl) methane, and 1,1-bis (4-dibenzylamino). Examples include phenyl) propane and 2,2'-dimethyl-4,4'-bis (diethylamino) -triphenylmethane.

Examples of the compound represented by the general formula (5) include 9- (4-
Diethylaminostyryl) anthracene, 9-bromo-10
-(4-diethylaminostyryl) anthracene and the like.

Examples of the compound represented by the general formula (6) include 9- (4-
Examples include dimethylaminobenzylidene) fluorene and 3- (9-fluorenylidene) -9-ethylcarbazole.

Examples of the compound represented by the general formula (7) include 1,2-bis (4-diethylaminostyryl) benzene and 1,2-bis (2,4-dimethoxystyryl) benzene.

Examples of the compound represented by the general formula (8) include 3-styryl-9-ethylcarbazole and 3- (4-methoxystyryl) -9-ethylcarbazole.

Examples of the compound represented by the general formula (9) include 4-diphenylaminostilbene, 4-dibenzylaminostilbene, 4-ditolylaminostilbene, 1- (4-diphenylaminostyryl) naphthalene, 1- (4 -Diethylaminostyryl) naphthalene etc.

The compound represented by the general formula (10) includes, for example, 4'-
Examples include diphenylamino-α-phenylstilbene and 4′-methylphenylamino-α-phenylstilbene.

Examples of the compound represented by the general formula (11) include 1-phenyl-3- (4-diethylaminostyryl) -5- (4-diethylaminophenyl) pyrazoline and 1-phenyl-3- (4-dimethylaminostyryl). -5- (4-dimethylaminophenyl) pyrazoline etc.

Other hole-transporting substances include, for example, 2,5-bis (4-
Diethylaminophenyl) -1,3,4-oxadiazole,
2,5-bis [4- (4-diethylaminostyryl) phenyl]
Oxadiazole compounds such as -1,3,4-oxadiazole and 2- (9-ethylcarbazolyl-3-)-5- (4-diethylaminophenyl) -1,3,4-oxadiazole , 2-vinyl-4- (2-chlorophenyl) -5- (4-diethylaminophenyl) oxazole, 2- (4-diethylaminophenyl)
There are low-molecular compounds such as oxazole compounds such as -4-phenyloxazole. Further, polymer compounds such as poly-N-vinylcarbazole, halogenated poly-N-vinylcarbazole, polyvinylpyrene, polyvinylanthracene, pyreneformaldehyde resin, ethylcarbazoleformaldehyde resin can also be used.

Examples of the charge carrier substance include chloranil, bromanil, tetracyanoethylene, tetracyanoquinone dimethane, 2,4,7-trinitro-9-fluorenone, 2,4,5,
7-tetranitro-9-fluorenone, 2,4,5,7-tetranitroxanthone, 2,4,8-trinitrothioxanthone, 2,6,
Examples include 8-trinitro-4H-indeno [1,2-b] thiophen-4-one and 1,3,7-trinitrodibenzothiophen-5,5-dioxide.

These charge carrier substances may be used alone or in combination of two or more.

In each of the photoreceptors obtained as described above, an adhesive layer or a barrier layer may be provided between the conductive support and the photosensitive layer, if necessary. Polyamide, nitrocellulose, aluminum oxide and the like are suitable as materials used for these layers, and the film thickness is preferably 1 μm or less.

To prepare the photoreceptor of FIG. 1, the bisazo pigment is vacuum-deposited on the conductive support by the vacuum deposition method described in USP3,973,959, USP3,996,049, or fine particles of the bisazo pigment are used. If necessary, disperse in a suitable solvent in which the binder is dissolved, apply this on a conductive support and dry,
Further, if necessary, for example, a solution containing a charge carrier substance and a binder is prepared by surface finishing by a method such as buffing as disclosed in JP-A-51-90827 or after adjusting the film thickness. It is obtained by applying and drying.

To prepare the photoreceptor of FIG. 2, fine powder of a bisazo pigment is dispersed in a solution in which a charge carrier substance and a binder are dissolved, and this is coated and dried on a conductive support.

In any case, the bisazo pigment used in the present invention is pulverized with a ball mill or the like to have a particle size of 5 μm or less, preferably 2 μm or less. The coating method is carried out by a usual method such as doctor blade, dipping, wire bar or the like.

In order to perform copying using the photoreceptor of the present invention, the surface of the photosensitive layer is charged and exposed, and then development is carried out.
This is achieved by transferring to paper or the like.

Next, the present invention will be specifically described with reference to examples, but the embodiments of the present invention are not limited thereby.

Example 1 76 parts by weight of bisazo pigment No. 121, 1260 parts by weight of a solution of a polyester resin (Vylon 200 manufactured by Toyobo Co., Ltd.) in tetrahydrofuran (solid concentration 2%), and 3700 parts by weight of tetrahydrofuran were ground in a ball mill. The obtained dispersion liquid was mixed and applied on the aluminum surface of an aluminum-deposited polyester base (conductive support) using a doctor blade, and naturally dried to form a charge generation layer having a thickness of about 1 μm.

On this charge generation layer, 2 parts by weight of 9-ethylcarbazole-3-aldehyde 1-methyl-1-phenylhydrazone as a charge carrier, 2 parts by weight of a polycarbonate resin (Panlite K-1300 manufactured by Teijin Ltd.) and 16 parts of tetrahydrofuran were used. A solution prepared by mixing and dissolving parts by weight was applied using a doctor blade and dried at 80 ° C. for 2 minutes and then at 105 ° C. for 5 minutes to form a charge transport layer having a thickness of about 20 μm, as shown in FIG. Laminated photoconductor No. 1 was prepared.

Examples 2 to 8 Instead of the bisazo pigment No. 121 used in Example 1, the following table-
Photoreceptor Nos. 2 to 8 were prepared in the same manner as in Example 1 except that the bisazo pigment shown in 1 was used.

Examples 9 to 24 Examples except that 1-phenyl-3- (4-diethylaminostyryl) -5- (4-diethylaminophenyl) pyrazoline was used as the charge carrier substance and the bisazo pigment shown in Table 2 below was used. Photoreceptor Nos. 9 to 24 were prepared in the same manner as in No. 1.

Examples 25 to 34 Photoreceptor No. was carried out in the same manner as in Example 1 except that α-phenyl-4′-N, N-diphenylaminostilbene was used as the charge carrier substance and the bisazo pigment shown in Table 3 below was used. .twenty five
Created ~ 34.

Examples 35 to 40 Photosensitive members were prepared in the same manner as in Example 1 except that 1,1-bis (4-dibenzylaminophenyl) propane was used as the charge carrier substance and the bisazo pigments shown in Table 4 below were used. No.35 ~ 4
Created 0.

These photoconductor Nos. 1 to 40 were tested with an electrostatic copying paper tester (SP428 type manufactured by Kawaguchi Electric Co., Ltd.) at -6 KV.
After corona discharge for 20 seconds to make it negatively charged,
It is left in the dark for 2 seconds, the surface potential Vpo (V) at that time is measured, and then light is irradiated by a tungsten lamp so that the surface has an illuminance of 4.5 lux, and the surface potential is ¹ / Vpo. seek time (in seconds) until the ₂ to calculate the exposure amount ^E _1/2 (Rutsukusu · sec). The results are shown in Table-1 to Table-4.

Effect As is clear from the results shown in Tables 1 to 4, the photoconductor of the present invention uses the bisazo pigment of the general formula (I) as a charge generating substance, and thus has high sensitivity.

Further, the photoconductors No. 5 and No. 26 of the present invention were mounted on a Ricoh Copier Recopy P-500 model to produce an image of 10,000.
As a result, a clear image was obtained without changing any of the photoconductors due to the repetition of the copying process. From this, it can be understood that the photoreceptor of the present invention is also excellent in durability.

[Brief description of drawings]

1 and 2 are enlarged cross-sectional views showing a constitutional example of the photoconductor of the present invention. 11 ... Conductive support, 13 ... Bisazo pigment 15 ... Charge generation layer, 17 ... Charge transport layer 191,192 ... Photosensitive layer

Claims (1)

[Claims] 1. A compound of general formula (I) on a conductive support. (However, A represents a Kuppler residue, R may be the same or different, and a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted aryl group, benzoyl Group, a cyano group, a substituted amino group, a nitro group, an acetyl group, or a carboxyl group or an ester thereof, and n represents an integer of 1 to 4), a layer containing a bisazo pigment is formed. Characteristic electrophotographic photoconductor.