JP2853351B2 - Electrophotographic photoreceptor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photoreceptor for electrophotography, and more particularly, to a photoreceptor formed on a conductive substrate, wherein the photoreceptor has the general formula (I), (III), (V) or (VII). The present invention relates to an electrophotographic photoreceptor containing an azo compound represented by any one of the above.

[0002]

2. Description of the Related Art Conventionally, as a photosensitive material for an electrophotographic photoreceptor (hereinafter simply referred to as a photoreceptor), an inorganic photoconductive substance such as selenium or a selenium alloy, and an inorganic photoconductive substance such as zinc oxide or cadmium sulfide have been used. Dispersed in a resin binder, an organic photoconductive substance such as poly-N-vinylcarbazole or polyvinylanthracene, an organic photoconductive substance such as a phthalocyanine compound or a bisazo compound, or these organic photoconductive substances What is dispersed in a binder is used.

A photoreceptor is required to have a function of retaining a surface charge in a dark place, a function of receiving light to generate a charge, and a function of receiving light and transporting a charge. A so-called single-layer type photoreceptor that combines these functions in layers, and a layer that separates functions into a layer that mainly contributes to charge generation and a layer that contributes to charge retention and surface transport in dark places and to charge transport during photoreception. There is a so-called laminated type photoreceptor in which are laminated.

For image formation by electrophotography using these photoconductors, for example, the Carlson method is applied. Image formation by this method involves charging a photoreceptor by corona discharge in a dark place, forming an electrostatic latent image such as a character or picture on a document by exposing the charged photoreceptor surface, and forming the formed electrostatic image. The latent image is developed by toner, and the developed toner image is transferred to a support such as paper and fixed. After the toner image is transferred, the photoconductor is subjected to static elimination, removal of residual toner, light neutralization, and the like. Provided for reuse.

In recent years, electrophotographic photoreceptors using organic materials have been put to practical use due to advantages such as flexibility, thermal stability, and film forming properties. For example, a photoreceptor composed of poly-N-vinylcarbazole and 2,4,7-trinitrofluoren-9-one (described in U.S. Pat. No. 3,484,237), Kaisho 47
Japanese Patent Application Laid-Open No. 47-10785), and a photoreceptor containing a eutectic complex comprising a dye and a resin as a main component (JP-A-47-10785).
Described in the official gazette). In addition, new azo compounds,
Many perylene compounds have also been put to practical use.

[0006]

However, although organic materials have many advantages over inorganic materials, those which sufficiently satisfy all the characteristics required for the photoreceptor in the above-described image forming process have been obtained. There is no present,
A photoreceptor having high sensitivity and excellent repetition characteristics is strongly desired.

An object of the present invention is to provide a photosensitive member having high sensitivity and excellent repetition characteristics by using a novel azo compound as a charge generating material of the photosensitive member.

[0008]

According to the present invention, an object of the present invention is to provide a photosensitive layer provided on a conductive substrate as a charge generating substance having a coupler component Cp represented by the following general formula (II).
_The problem is solved by providing a photoreceptor containing an azo compound represented by the following general formula (I) having _1:

[0009]

Embedded image

[In the formula (I), A is a substituted or unsubstituted aromatic hydrocarbon group or aromatic heterocyclic group, or a single bond,

Embedded image -CH = N-, -CO-, -O-, -S-, -CONH
—, —NX—, —CH ₂ — (m represents an integer 1 or 2, X represents a hydrogen atom, an alkyl group which may be substituted,
Or a phenyl group).
p ₁ is represented by the following general formula (II), and n represents an integer 1, 2 or 3. ]

[0011]

Embedded image

[In the formula (II), R ₁ represents an alkyl group or an aryl group which may be substituted, and R ₂ represents a hydrogen atom, a cyano group, a carbamoyl group, a carboxyl group, an ester group or an acyl group. Indicates one of them. ]

Further, the following general formula (I)
The problem is solved by providing a photoreceptor containing an azo compound represented by the following general formula (III) having a coupler component Cp ₂ represented by V).

[0014]

Embedded image

[In the formula (III), A represents a substituted or unsubstituted aromatic hydrocarbon group or aromatic heterocyclic group, or a single bond thereof.

Embedded image -CH = N-, -CO-, -O-, -S-, -CONH
—, —NX—, —CH ₂ — (m represents an integer 1 or 2, X represents a hydrogen atom, an alkyl group which may be substituted,
Or a phenyl group).
p ₂ is represented by the following general formula (IV), and n represents an integer 1, 2 or 3. ]

[0016]

Embedded image

[In the formula (IV), R ₁ represents an alkyl group or an aryl group which may be substituted, and R ₂ represents a hydrogen atom, a cyano group, a carbamoyl group, a carboxyl group, an ester group or an acyl group. Indicates one of them. ]

Further, the following general formula (V
It is solved by a photoreceptor containing an azo compound represented by the following general formula (V) having a coupler component Cp ₃ represented by I).

[0019]

Embedded image

[In the formula (V), A represents a substituted or unsubstituted aromatic hydrocarbon group, an aromatic hetero group or a single bond,

Embedded image -CH = N-, -CO-, -O-, -S-, -CONH
—, —NX—, —CH ₂ — (m represents an integer 1 or 2, X represents a hydrogen atom, an alkyl group which may be substituted, or a phenyl group), and R ₁ represents Represents any of a hydrogen atom, a halogen atom, a nitro group, an alkyl group which may be substituted or an alkoxy group, Cp ₃ is represented by the formula (VI), and n represents an integer 1, 2 or 3. ]

[0021]

Embedded image

[In the formula (II), R ₂ represents an alkyl group or an aryl group which may be substituted, and R ₃ represents a hydrogen atom, a cyano group, a carbamoyl group, a carboxyl group, an ester group or an acyl group. Indicates one of them. ]

Further, the following general formula having a coupler component represented by the following general formula (VIII) as a charge generating substance:
The problem is solved by providing a photoreceptor containing the azo compound represented by the formula (VII).

[0024]

Embedded image

[In the formula (VII), A represents a substituted or unsubstituted aromatic hydrocarbon group, an aromatic hetero group or a single bond,

Embedded image -CH = N-, -CO-, -O-, -S-, -CONH
—, —NX—, —CH ₂ — (m represents an integer 1 or 2, X represents a hydrogen atom, an alkyl group which may be substituted, or a phenyl group), and R ₁ represents Represents any of a hydrogen atom, a halogen atom, a nitro group, an alkyl group or an alkoxy group which may be substituted, Cp ₄ is represented by the formula (VIII), and n represents an integer 1, 2 or 3. ]

[0026]

Embedded image

[In the formula (VIII), R ₂ represents an alkyl group or an aryl group which may be substituted, and R ₃ represents a hydrogen atom, a cyano group, a carbamoyl group, a carboxyl group, an ester group or an acyl group. Indicates one of them. ]

The photosensitive layer may be a single layer containing the charge generating substance as a whole, or may be a laminate of a charge generating layer containing the charge generating substance and a charge transporting layer. .

The azo compound of the general formula (I) used in the present invention is obtained by diazotizing (or tetrazolating or hexazolating) an aromatic amino compound with nitrous acid by a conventional method.
And a salt thereof and a coupler component C represented by the general formula (II)
By reacting p ₁ with a base (such as sodium acetate) in a suitable organic solvent such as N, N-dimethylformamide (DMF) to cause a coupling reaction,
It can be synthesized as shown in Scheme 1 below.

[0030]

Embedded image

The coupler component Cp ₁ of the general formula (II)
Can be synthesized as follows. First, cyaminopyridine and ethyl dianoacetate are condensed to obtain cyanomethylpyridimidazole (at this time, a mixture of isomers is formed, but used as it is). The obtained imidazole derivative is converted to ethyl acetoacetate (or an analog thereof).
By condensing with, for example, a dipyridimidazole derivative represented by the formula (II) can be obtained as shown in the following scheme 2.

[0032]

Embedded image

The azo compound of the general formula (III) is
As in the case of the above-mentioned azo compound of the general formula (I), the aromatic amino compound is diazotized (or tetrazotized, hexazotized) with nitrous acid by a conventional method, and the salt thereof is represented by the general formula (IV). coupler component Cp ₂ a suitable organic solvent such as N, N-dimethylformamide (DMF) in by the action of bases (sodium acetate, etc.), for example, by coupling reaction, be synthesized in the following manner scheme 3 Can be.

[0034]

Embedded image

The coupler component Cp ₂ of the general formula (IV) is the same as the coupler component Cp ₁ of the general formula (II).
In the same manner as in the above case, the synthesis can be performed as follows. First, diaminopyrimidine and ethyl cyanoacetate are condensed to obtain cyanomethylpurine (in this case, a mixture of isomers is formed, but used as it is). By condensing the obtained imidazole derivative with ethyl acetoacetate (or an analog thereof), for example, the following Scheme 4
Thus, a pyridopurine derivative represented by the formula (IV) can be obtained.

[0036]

Embedded image

Further, the azo compound of the general formula (V) is
The aromatic amino compound is diazotized with nitrous acid by a conventional method, and the salt thereof and the aniline are coupled in the presence of a base. Thereafter, the compound can be diazotized again and reacted with the coupler component represented by the general formula (VI) to synthesize, for example, as shown in the following scheme 5.

[0038]

Embedded image

Further, the azo compound of the general formula (VII) is obtained by diazotizing an aromatic amino compound with nitrous acid by a conventional method, and coupling the salt thereof with an aniline in the presence of a base. Thereafter, the compound is diazotized again, and the compound of the general formula (VII
By reacting the coupler component shown in I),
For example, it can be synthesized as shown in Scheme 6 below.

[0040]

Embedded image

[0041] Thus examples of the coupler component Cp ₁ represented by the general formula obtained (II) in Table 1, the formula in Table 2 to Table 13 Specific examples of the azo compounds represented by (I)
An example is shown below.

[0042]

[Table 1]

[0043]

[Table 2]

[0044]

[Table 3]

[0045]

[Table 4]

[0046]

[Table 5]

[0047]

[Table 6]

[0048]

[Table 7]

[0049]

[Table 8]

[0050]

[Table 9]

[0051]

[Table 10]

[0052]

[Table 11]

[0053]

[Table 12]

[0054]

[Table 13]

Table 14 shows specific examples of the coupler component Cp ₂ represented by the general formula (IV).
Specific examples of the azo compound represented by are shown in Tables 15 to 26.

[0056]

[Table 14]

[0057]

[Table 15]

[0058]

[Table 16]

[0059]

[Table 17]

[0060]

[Table 18]

[0061]

[Table 19]

[0062]

[Table 20]

[0063]

[Table 21]

[0064]

[Table 22]

[0065]

[Table 23]

[0066]

[Table 24]

[0067]

[Table 25]

[0068]

[Table 26]

Table 27 shows specific examples of the coupler component Cp ₃ represented by the general formula (VI).
Specific examples of the azo compound represented by are shown in Tables 28 to 39.

[0070]

[Table 27]

[0071]

[Table 28]

[0072]

[Table 29]

[0073]

[Table 30]

[0074]

[Table 31]

[0075]

[Table 32]

[0076]

[Table 33]

[0077]

[Table 34]

[0078]

[Table 35]

[0079]

[Table 36]

[0080]

[Table 37]

[0081]

[Table 38]

[0082]

[Table 39]

[0083] Also, specific examples of the coupler component Cp ₄ represented by the general formula (VIII) in Table 40, the general formula (VII)
Specific examples of the azo compound represented by are shown in Tables 41 to 52.

[0084]

[Table 40]

[0085]

[Table 41]

[0086]

[Table 42]

[0087]

[Table 43]

[0088]

[Table 44]

[0089]

[Table 45]

[0090]

[Table 46]

[0091]

[Table 47]

[0092]

[Table 48]

[0093]

[Table 49]

[0094]

[Table 50]

[0095]

[Table 51]

[0096]

[Table 52]

[0097]

By using a specific azo compound represented by any of the above formulas (I), (III), (V) and (VII) as a charge generating substance in the photosensitive layer, high sensitivity can be obtained. A photoreceptor having excellent repetition characteristics can be obtained. The effect of using the azo compound described above does not change depending on the layer configuration of the photosensitive layer.

[0098]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The photoreceptor of the present invention has the general formulas (I) and (II)
The photosensitive layer contains an azo compound represented by any one of (I), (V) and (VII). Depending on the application method of these azo compounds, FIGS. 3 can be used.

1 to 3 are conceptual cross-sectional views of the photoreceptor of the present invention, wherein 1 is a conductive substrate, 2a, 2b and 2c are photosensitive layers, 3 is a charge generating substance, 4 is a charge generating layer, and 5 is a charge generating layer. The charge transport material, 6 is a charge transport layer, and 7 is a coating layer.

FIG. 1 shows that a charge generation material 3 is placed on a conductive substrate 1.
And a photosensitive layer 2a (usually referred to as a single-layer type photoreceptor) in which the azo compound and the charge transport material 5 are dispersed in a resin binder (binder).

FIG. 2 shows that the charge generation material 3
Provided with a photosensitive layer 2b (usually referred to as a laminated photoreceptor) composed of a laminate of a charge generating layer 4 containing an azo compound and a charge transporting layer 6 mainly composed of a charge transporting substance 5. is there.

FIG. 3 shows a case where a photosensitive layer having a layer structure opposite to that of FIG. 2 is provided. In this configuration, a coating layer 7 is usually further provided to protect the charge generation layer 4.

The reason why the layer structure shown in FIGS. 2 and 3 is adopted is that the layer structure shown in FIG. 2 is usually used as a negative charging system. At present, no charge transport material suitable for the positive charging method has been found in the layer configuration shown in FIG. Therefore, at present, a layer structure shown in FIG. 3 is required as a positively charged photosensitive member.

The photoreceptor shown in FIG. 1 can be produced by dispersing a charge generating substance in a solution in which a charge transporting substance and a resin binder are dissolved, and applying this dispersion on a conductive substrate.

In the photoreceptor of FIG. 2, a dispersion obtained by dispersing particles of a charge generating substance in a solvent or a resin binder on a conductive substrate is applied and dried, and then a charge transporting substance and a resin binder are coated thereon. It can be produced by applying and drying a dissolved solution.

The photoreceptor shown in FIG. 3 is obtained by applying a solution in which a charge transport material and a resin binder are dissolved on a conductive substrate, drying the solution, and dispersing the particles of the charge generation material in a solvent or a resin binder. It can be produced by applying the dried dispersion, drying, and forming a coating layer thereon.

The conductive substrate 1 serves not only as the electrode of the photosensitive member but also as a support for the other layers, and may be cylindrical, plate-like or film-like. Conductive treatment may be performed on a metal such as nickel, glass, resin, or the like.

The charge generation layer 4 is made of the general formulas (I) and (II)
I), (V), and (VII) are formed by applying a material in which particles of the charge generating substance 3 which is an azo compound represented by any of (I), (V) and (VII) are dispersed in a resin binder. Occurs. In addition, it is important that the charge generation efficiency is high and at the same time, the generated charge is injected into the charge transporting layer 6 and the coating layer 7. The charge generation layer may be mainly composed of a charge generation substance, to which a charge transport substance or the like is added. As the resin binder, polycarbonate, polyester, polyamide, polyurethane, epoxy, silicone resin, polymers and copolymers of methacrylic acid esters, and the like can be used alone or in an appropriate combination.

The charge transport layer 6 dissolves a hydrazone compound, a pyrazoline compound, a styryl compound, a triphenylamine compound, an oxazole compound, an oxadiazole compound as an organic charge transport material in a resin binder.
It is formed by applying a dispersed material, and has a function of retaining charges of the photoreceptor as an insulator layer in a dark place and transporting charges injected from the charge generation layer when receiving light. As resin binder, polycarbonate, polyester,
Epoxy resins, silicone resins, polymers and copolymers of methacrylic acid esters, and the like can be used.

The coating layer 7 has a function of receiving and holding the charge of corona discharge in a dark place, and has a function of transmitting light which the charge generation layer responds to.
It is necessary to reach the charge generation layer and neutralize the surface charge by injection of the generated charge.

As the coating material, an organic insulating film forming material such as polyester and polyamide can be used. In addition, a mixture of these organic materials and an inorganic material such as a glass resin or SiO _2, or a material such as a metal or a metal oxide that reduces electric resistance can be used. The coating material is not limited to an organic insulating film forming material, but may be an inorganic material such as SiO _2, or a metal, a metal oxide, or the like, formed by a method such as evaporation or sputtering. As described above, it is desirable that the coating material is as transparent as possible in the wavelength region where the light absorption of the charge generating substance is maximum.

Although the thickness of the coating layer itself depends on the composition of the coating layer, it can be arbitrarily set within a range where adverse effects such as an increase in residual potential do not occur when used repeatedly and continuously.

An embodiment of the present invention will be described below.

Example 1 50 parts by weight of the azo compound represented by the above compound No. I-16 was combined with 100 parts by weight of a polyester resin (trade name: Byron 200, manufactured by Toyobo) and 1-phenyl-3- (p-diethylaminostyryl)- 100 parts by weight of 5- (p-diethylaminophenyl) -2-pyrazoline (ASPP) and a solvent of tetrahydrofuran (THF) are kneaded with a mixer for 3 hours to prepare a coating solution, and an aluminum-evaporated polyester film (Al -PET), a photosensitive layer was formed by applying a wire bar method, and a photosensitive layer was formed so that the film thickness after drying was 15 μm, thereby producing a photosensitive member having a configuration shown in FIG.

Example 2 First, a solution prepared by dissolving 100 parts by weight of p-diethylaminobenzaldehyde-diphenylhydrazone (ABPH) in 700 parts by weight of tetrahydrofuran (THF) and a polycarbonate resin (trade name: Panlite L-1250: manufactured by Teijin Limited) 100 Parts by weight of THF and dichloromethane
A coating solution obtained by mixing a solution dissolved in 700 parts by weight of a mixed solvent was applied on an aluminum-evaporated polyester film substrate by a wire bar method, and a charge transport layer was formed so that the film thickness after drying was 15 μm. . On the thus obtained charge transport layer, 50 parts by weight of the azo compound represented by the compound No. I-1 and a polyester resin (trade name: Byron 20)
0: manufactured by Toyobo Co., Ltd.) and kneaded with a THF solvent for 3 hours using a mixer to prepare a coating solution, apply it by a wire bar method, and form a charge generation layer so that the film thickness after drying becomes 0.5 μm. Formed. Further, a coating layer was formed thereon to produce a photoreceptor having the structure shown in FIG.

Example 3 In Example 2, the charge-transporting substance was changed from ABPH to α-phenyl-4′-N, N-dimethylaminostilbene which is a styryl compound, and the other conditions were the same as in Example 2. Was prepared.

Example 4 A photoconductor was prepared by the same way as that of Example 2 except that the charge transporting substance was changed from ABPH to tri (p-tolyl) amine which is a triphenylamine compound.

Example 5 In Example 2, the charge transporting substance was changed from ABPH to 2,5-bis (p-diethylaminophenyl) -1,3,4-oxadiazole which is an oxadiazole compound. A photoconductor was produced in the same manner as in Example 2.

The electrophotographic characteristics of the photoreceptor thus obtained were evaluated by using an electrophotographic recording paper tester “SP-42” manufactured by Kawaguchi Electric.
8 ". Table 9 shows the results.

The surface potential V _S (volt) of the photoreceptor is an initial surface potential when the surface of the photoreceptor is positively charged by performing a corona discharge of +6.0 kV for 10 seconds in a dark place. The surface potential V _d (volt) when the dark state was maintained for 2 seconds in the stopped state was measured, and subsequently, the time until the V _d was reduced to half by irradiating the surface of the photoreceptor with white light having an illuminance of 2 lux ( Second) and the half-attenuation exposure amount E _1/2 (looks / second). In addition, white light with an illuminance of 2
Surface potential when irradiated for 2 seconds is residual potential _Vr (volt)
And

[0121]

[Table 53]

As can be seen from Table 53, Examples 1, 2 and
Samples 3, 4, and 5 had good half-attenuation exposure and residual potential. In addition, the surface potential and the residual potential when charging / exposure was repeated did not fluctuate much, and had good repetition characteristics.

Example 6 100 parts by weight of the azo compounds represented by the compounds No. I-1 to No. I-47 were mixed with 100 parts by weight of a polyester resin (trade name: Byron 200, manufactured by Toyobo Co., Ltd.) together with a THF solvent for 3 hours. A coating solution was prepared by kneading with an applicator, and applied on an aluminum support so as to have a thickness of about 0.5 μm to form a charge generation layer. On top of this, a charge transport layer was formed by changing the ABPH in Example 2 to ASPP, and applying a coating liquid using ASPP as a charge transport material prepared in the same manner as in Example 2 to a thickness of about 15 μm. A photoconductor having the configuration shown in FIG. 2 was produced.

The electrophotographic characteristics of the photoreceptor thus obtained were evaluated by using a Kawaguchi Electric Co., Ltd. electrostatic recording paper tester “SP-42”.
8 ", and the corona discharge voltage is increased from +6.0 kV to -6.
The measurement was performed in the same manner as in the case of the photoconductors of Examples 1 to 5 except that the voltage was changed to 0 kV. Of the measurement results, the half decay exposure amount E _1/2 and residual potential V _r values Table 54 to Table 56
Shown in

[0125]

[Table 54]

[0126]

[Table 55]

[0127]

[Table 56]

As can be seen from Tables 54 to 56, the photoreceptors using the azo compounds represented by the compounds No. I-1 to No. I-47 as the charge-generating substances have the half-attenuation exposure amounts E _1/2 ,
Both the residual potential _Vr was good. In addition, there is little fluctuation in surface potential and residual potential when charging and exposure are repeated,
It had good repetition characteristics.

Example 7 100 parts by weight of a polyester resin (trade name: Byron 200, manufactured by Toyobo) was mixed with 50 parts by weight of the azo compound represented by the above compound No. III-18 and 1-phenyl-3- (p-diethylaminostyryl)- 100 parts by weight of 5- (p-diethylaminophenyl) -2-pyrazoline (ASPP) and a tetrahydrofuran (THF) solvent are kneaded with a mixer for 3 hours to prepare a coating solution, and an aluminum-evaporated polyester film (Al -PET), a photosensitive layer was formed by applying a wire bar method, and a photosensitive layer was formed so that the film thickness after drying was 15 μm, thereby producing a photosensitive member having a configuration shown in FIG.

Example 8 First, a solution prepared by dissolving 100 parts by weight of p-diethylaminobenzaldehyde-diphenylhydrazone (ABPH) in 700 parts by weight of tetrahydrofuran (THF) and 100 parts by weight of a polycarbonate resin (trade name Panlite L-1250: manufactured by Teijin) Part is 1: 1 of THF and dichloromethane
A coating solution formed by mixing a solution dissolved in 700 parts by weight of a mixed solvent is applied on an aluminum-evaporated polyester film substrate by a wire bar method, and the charge transport layer is dried so that the film thickness becomes 15 μm. Formed. On the thus obtained charge transport layer, 50 parts by weight of the azo compound represented by the above compound No. III-1 and a polyester resin (trade name: Byron 2)
00: manufactured by Toyobo) 50 parts by weight together with a THF solvent
The coating solution was adjusted by kneading with a time mixer and applied by a wire bar method, and a charge generation layer was formed so that the film thickness after drying was 0.5 μm. Further, a coating layer was formed thereon to produce a photoreceptor having the structure shown in FIG.

Example 9 A photoconductor was prepared in the same manner as in Example 8 except that the charge transporting substance was changed from ABPH to α-phenyl-4′-N, N-dimethylaminostilbene which is a styryl compound. Produced.

Example 10 A photoconductor was prepared by the same way as that of Example 8 except that the charge transporting substance was changed from ABPH to tri (p-tolyl) amine which is a triphenylamine compound.

Example 11 In Example 8, the charge transporting substance was changed from ABPH to 2,5-bis (p-diethylaminophenyl) -1,3,4-oxadiazole which is an oxadiazole compound. A photoconductor was prepared in the same manner as in Example 8.

The electrophotographic characteristics of the photoreceptor thus obtained were measured using Kawaguchi Denki's electrostatic recording paper tester “SP-42”.
8 "in the same manner as in the case of the photoconductors of Examples 1 to 5. Table 57 shows the measurement results.

[0135]

[Table 57]

As can be seen in Table 57, Examples 7, 8,
Samples 9, 10 and 11 had good half-attenuated exposure and residual potential. In addition, the surface potential and the residual potential when charging / exposure was repeated did not fluctuate much, and had good repetition characteristics.

Example 12 100 parts by weight of the azo compounds represented by the compounds No. III-1 to No. III-47 were mixed with 100 parts by weight of a polyester resin (trade name: Byron 200, manufactured by Toyobo) for 3 hours together with a THF solvent. A coating solution was prepared by kneading with an applicator, and applied on an aluminum support so as to have a thickness of about 0.5 μm to form a charge generation layer. On top of this, a charge transport layer was formed by changing the ABPH in Example 8 to ASPP and applying a coating liquid containing ASPP as a charge transport material prepared in the same manner as in Example 8 to a thickness of about 15 μm. A photoconductor having the configuration shown in FIG. 2 was produced.

The electrophotographic characteristics of the photoreceptor thus obtained were evaluated by using an electrostatic recording paper tester “SP-428” manufactured by Kawaguchi Electric.
And measured in the same manner as in the case of the photoconductor of Example 6. Of the measurement results, showing the value of the half-attenuation exposure E _1/2 and residual potential V _r in Table 58 to Table 60.

[0139]

[Table 58]

[0140]

[Table 59]

[0141]

[Table 60]

As can be seen from Tables 58 to 60, the photoreceptors using the azo compounds represented by the compounds No. III-1 to No. III-47 as the charge generating substances have a half-attenuation exposure E _1/2 ,
Both the residual potential _Vr was good. In addition, fluctuations in surface potential and residual potential when charging and exposure are repeated are small,
It had good repetition characteristics.

Example 13 50 parts by weight of the azo compound represented by the above compound No. V-19 was mixed with a polyester resin (Vylon 200: Toyobo) 1
00 parts by weight and 1-phenyl-3- (p-diethylaminostyryl) -5- (p-diethylaminophenyl) -2
-A coating liquid is prepared by kneading 100 parts by weight of pyrazoline (ASPP) and a solvent of tetrahydrofuran (THF) with a mixer for 3 hours to prepare a coating solution, and a wire bar method is applied on an aluminum-evaporated polyester film (Al-PET) as a conductive substrate. The photosensitive member having the configuration shown in FIG. 1 was prepared by applying the film and forming the film to have a thickness of 15 μm after drying.

Example 14 First, a solution prepared by dissolving 100 parts by weight of p-diethylaminobenzaldehyde-diphenylhydrazone (ABPH) in 700 parts by weight of tetrahydrofuran (THF) was mixed with a polycarbonate resin (PANLITE L-1250: manufactured by Teijin Limited).
A coating solution prepared by mixing 00 parts by weight with a solution prepared by dissolving 700 parts by weight of a 1: 1 mixed solvent of THF and dichloromethane is applied to an aluminum-evaporated polyester film substrate by a wire bar method, and the film thickness after drying is obtained. Was 15 μm. The azo compound 50 represented by the above compound No. V-1 was formed on the charge transport layer thus obtained.
Parts by weight and a polyester resin (trade name: Byron 200:
50 parts by weight (Toyobo Co., Ltd.) and a THF solvent were kneaded with a mixer for 3 hours to prepare a coating solution, which was applied by a wire bar method, and a charge generation layer was formed so that the film thickness after drying was 0.5 μm. Then, a coating layer was further formed thereon to produce a photoreceptor having the structure shown in FIG.

Example 15 In Example 14, the charge transport material was changed from ABPH to a styryl compound, α-phenyl-4′-N, N-dimethylaminostilbene, and the other conditions were the same as in Example 14. Was prepared.

Example 16 A photoconductor was prepared by the same way as that of Example 14 except that the charge transporting substance was changed from ABPH to tri (p-tolyl) amine, which is a triphenylamine compound.

Example 17 In Example 14, the charge-transporting substance was changed from ABPH to 2,5-bis (p-diethylaminophenyl) -1,3,4-oxadiazole which is an oxadiazole compound. A photoconductor was produced in the same manner as in Example 2.

The electrophotographic characteristics of the photoreceptor thus obtained were evaluated by using an electrostatic recording paper tester “SP-428” manufactured by Kawaguchi Electric.
Was measured in the same manner as in the case of the photoconductors of Examples 1 to 5. Table 13 shows the measurement results.

[0149]

[Table 61]

As can be seen from Table 61, Examples 13 and 1
Nos. 4, 15, 16 and 17 exhibited good half-attenuation exposure and residual potential. In addition, the surface potential and the residual potential when charging / exposure was repeated did not fluctuate much, and had good repetition characteristics.

Example 18 100 parts by weight of the azo compounds represented by the compounds Nos. V-1 to V-47 were kneaded together with 100 parts by weight of a polyester resin (trade name: Byron 200) and a THF solvent by a mixer for 3 hours. Then, a coating solution was prepared and applied on an aluminum support so as to have a thickness of about 0.5 μm to form a charge generating layer. On this, a coating liquid containing ABPH obtained by the same method as that prepared in Example 14 and having a charge transporting substance was applied so as to have a thickness of about 15 μm to form a charge transporting layer, thereby producing a photoreceptor.

The electrophotographic characteristics of the photoreceptor thus obtained were evaluated by using an electrostatic recording paper tester “SP-428” manufactured by Kawaguchi Electric.
Was measured in the same manner as in the case of the photoconductor of Example 6. The value of the half decay exposure amount E _1/2 and residual potential V _r of the measurement results shown in Table 62-64 to.

[0153]

[Table 62]

[0154]

[Table 63]

[0155]

[Table 64]

As can be seen from Tables 62 and 64, the photoreceptors using the azo compounds represented by the compounds No. V-1 to No. V-47 as the charge generating substances have a half attenuation exposure
_{Both 1/2} and the residual potential _Vr were good. In addition,
The variation in surface potential and residual potential when exposure was repeated was small, and the device had good repetition characteristics.

Example 19 50 parts by weight of the azo compound represented by the above compound No. VII-17 was added to a polyester resin (Vylon 200: Toyobo) 1
00 parts by weight and 1-phenyl-3- (p-diethylaminostyryl) -5- (p-diethylaminophenyl) -2
-A coating liquid is prepared by kneading 100 parts by weight of pyrazoline (ASPP) and a solvent of tetrahydrofuran (THF) with a mixer for 3 hours to prepare a coating solution, and a wire bar method is applied on an aluminum-evaporated polyester film (Al-PET) as a conductive substrate. A photosensitive layer was formed so as to have a thickness of 15 μm after coating and drying, thereby producing a photosensitive member having the configuration shown in FIG.

Example 20 First, a solution prepared by dissolving 100 parts by weight of p-diethylaminobenzaldehyde-diphenylhydrazone (ABPH) in 700 parts by weight of tetrahydrofuran (THF) was mixed with a polycarbonate resin (Panlite L-1250: manufactured by Teijin).
A coating solution obtained by mixing 0 parts by weight with a solution prepared by mixing 700 parts by weight of a one-to-one mixed solvent of THF and dichloromethane is applied to an aluminum-evaporated polyester film substrate by a wire bar method, and the film thickness after drying is obtained. Was 15 μm. On the thus-obtained charge transporting layer, 50 parts by weight of the azo compound represented by the compound No. VII-1 was mixed with 50 parts by weight of a polyester resin (trade name: Byron 200, manufactured by Toyobo) and a THF solvent for 3 hours. To prepare a coating solution and apply it by a wire bar method,
A charge generating layer was formed so that the film thickness after drying became 0.5 μm, and a coating layer was further formed thereon to produce a photoreceptor having a configuration shown in FIG.

Example 21 In Example 20, the charge transporting substance was changed from ABPH to α-phenyl-4'-N, N-dimethylaminostilbene which is a styryl compound. Was prepared.

Example 22 A photoconductor was prepared by the same way as that of Example 20 except that the charge transporting substance was changed from ABPH to tri (p-tolyl) amine which is a triphenylamine compound.

Example 23 In Example 20, the charge transporting substance was changed from ABPH to 2,5-bis (p-diethylaminophenyl) -1,3,4-oxadiazole which is an oxadiazole compound. A photoconductor was prepared in the same manner as in Example 20.

The electrophotographic characteristics of the photoreceptor thus obtained were evaluated by using an electrostatic recording paper tester “SP-428” manufactured by Kawaguchi Electric.
Was measured in the same manner as in the case of the photoconductors of Examples 1 to 5. Table 65 shows the measurement results.

[0163]

[Table 65]

As can be seen from Table 65, Examples 19 and 2
0, 21, 22, and 23 exhibited good half-attenuated exposure and residual potential. In addition, the surface potential and the residual potential when charging / exposure was repeated did not fluctuate much, and had good repetition characteristics.

Example 24 100 parts by weight of the azo compounds represented by the compounds No. VII-1 to No. VII-47 were kneaded together with 100 parts by weight of a polyester resin (trade name: Byron 200) and a THF solvent by a mixer for 3 hours. Then, a coating solution was prepared and applied on an aluminum support so as to have a thickness of about 0.5 μm to form a charge generating layer. Further, a coating liquid containing ABPH obtained by the same method as that prepared in Example 20 and having a charge transporting substance was applied to a thickness of about 15 μm to form a charge transporting layer, thereby producing a photoreceptor.

The electrophotographic characteristics of the photoreceptor thus obtained were measured by using an electrostatic recording paper tester “SP-428” manufactured by Kawaguchi Electric.
Was measured in the same manner as in the case of the photoconductor of Example 6. Of the measurement results, the value of half-decay exposure amount E _1/2 and residual potential V _r are shown in Table 66-68.

[0167]

[Table 66]

[0168]

[Table 67]

[0169]

[Table 68]

As can be seen from Tables 66 and 68, the photoreceptors using the azo compounds represented by the compounds No. VII-1 to No. VII-47 as the charge-generating substances have the half-attenuation exposure E
_{Both 1/2} and the residual potential _Vr were good. In addition,
The variation in surface potential and residual potential when exposure was repeated was small, and the device had good repetition characteristics.

[0171]

According to the present invention, in the photosensitive layer provided on the conductive substrate, the above-mentioned general formula (I),
By using a bisazo compound represented by any of (III), (V) and (VII), a photoconductor for electrophotography having high sensitivity and excellent repetition characteristics can be obtained. The effect of using these azo compounds does not change depending on the layer configuration of the photosensitive layer, and by selecting the layer configuration,
It is possible to obtain a photoreceptor suitably used for positive charging or negative charging. Further, it is possible to improve the durability by providing a coating layer on the surface as needed.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view of one embodiment of a photoreceptor of the present invention.

FIG. 2 is a schematic sectional view of a different embodiment of the photoreceptor of the present invention.

FIG. 3 is a schematic sectional view of still another embodiment of the photoconductor of the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 conductive substrate 2 a photosensitive layer 2 b photosensitive layer 2 c photosensitive layer 3 charge generating substance 4 charge generating layer 5 charge transporting substance 6 charge transporting layer 7 coating layer

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) G03G 5/06 367

Claims (15)

(57) [Claims] _1. An azo compound represented by the following general formula (I) having a coupler component Cp1 represented by the following general formula (II) as a charge generating substance in a photosensitive layer provided on a conductive substrate. A photoconductor for electrophotography, comprising: Embedded image [In the formula (I), A represents a substituted or unsubstituted aromatic hydrocarbon group or an aromatic heterocyclic group, or a single bond thereof. -CH = N-, -CO-, -O-, -S-, -CONH
—, —NX—, —CH ₂ — (m represents an integer 1 or 2, X represents a hydrogen atom, an alkyl group which may be substituted,
Or a phenyl group).
p ₁ is represented by the following general formula (II), and n represents an integer 1, 2 or 3. [Chemical formula 3] [In the formula (II), R ₁ represents an alkyl group or an aryl group which may be substituted, and R ₂ represents a hydrogen atom, a cyano group,
It represents any one of a carbamoyl group, a carboxyl group, an ester group, and an acyl group. ] 2. The method according to claim 1, wherein the photosensitive layer contains an azo compound represented by the following formula as a charge generating substance.
The photoconductor for electrophotography according to the above. Embedded image 3. The photosensitive layer contains an azo compound represented by the following formula as a charge generating substance.
The photoconductor for electrophotography according to the above. Embedded image 4. An azo compound represented by the following general formula (III) having a coupler component Cp ₂ represented by the following general formula (IV) as a charge generating substance in a photosensitive layer provided on a conductive substrate. A photoconductor for electrophotography, comprising: Embedded image [In the formula (III), A represents a substituted or unsubstituted aromatic hydrocarbon group or an aromatic heterocyclic group, or a single bond thereof. -CH = N-, -CO-, -O-, -S-, -CONH
—, —NX—, —CH ₂ — (m represents an integer 1 or 2, X represents a hydrogen atom, an alkyl group which may be substituted,
Or a phenyl group).
p ₂ is represented by the following general formula (IV), and n represents an integer 1, 2 or 3. Embedded image [In the formula (IV), R ₁ represents an alkyl group or an aryl group which may be substituted, and R ₂ represents a hydrogen atom, a cyano group,
It represents any one of a carbamoyl group, a carboxyl group, an ester group, and an acyl group. ] 5. The photosensitive layer contains an azo compound represented by the following formula as a charge generating substance.
The photoconductor for electrophotography according to the above. Embedded image 6. A photosensitive layer containing an azo compound represented by the following formula as a charge generating substance:
The photoconductor for electrophotography according to the above. Embedded image 7. An azo compound represented by the following general formula (V) having a coupler component Cp ₃ represented by the following general formula (VI) in a photosensitive layer provided on a conductive substrate. A photoconductor for electrophotography, characterized by: Embedded image [In the formula (V), A represents a substituted or unsubstituted aromatic hydrocarbon group, an aromatic hetero group, or a single bond thereof. -CH = N-, -CO-, -O-, -S-, -CONH
—, —NX—, —CH ₂ — (m represents an integer 1 or 2, X represents a hydrogen atom, an alkyl group which may be substituted, or a phenyl group), and R ₁ represents Represents any of a hydrogen atom, a halogen atom, a nitro group, an alkyl group which may be substituted or an alkoxy group, Cp ₃ is represented by the formula (VI), and n represents an integer 1, 2 or 3. [Formula 13] [In the formula (VI), R ₂ represents an optionally substituted alkyl group or an aryl group, and R ₃ represents any one of a hydrogen atom, a cyano group, a carbamoyl group, a carboxyl group, an ester group, and an acyl group. Represents ] 8. The photosensitive layer contains an azo compound represented by the following formula as a charge generating substance.
The photoconductor for electrophotography according to the above. Embedded image 9. The photosensitive layer contains an azo compound represented by the following formula as a charge generating substance.
The photoconductor for electrophotography according to the above. Embedded image 10. A photosensitive layer provided on a conductive substrate, comprising an azo compound represented by the following general formula (VII) having a coupler component Cp ₄ represented by the following general formula (VIII). A photoconductor for electrophotography, characterized by: Embedded image [In the formula (VII), A represents a substituted or unsubstituted aromatic hydrocarbon group, an aromatic hetero group or a single bond thereof, -CH = N-, -CO-, -O-, -S-, -CONH
—, —NX—, —CH ₂ — (m represents an integer 1 or 2, X represents a hydrogen atom, an alkyl group which may be substituted, or a phenyl group), and R ₁ represents Represents any of a hydrogen atom, a halogen atom, a nitro group, an alkyl group or an alkoxy group which may be substituted, Cp ₄ is represented by the formula (VIII), and n represents an integer 1, 2 or 3. Embedded image [In the formula (VIII), R ₂ represents an alkyl group or an aryl group which may be substituted, and R ₃ represents a hydrogen atom, a cyano group,
It represents any one of a carbamoyl group, a carboxyl group, an ester group, and an acyl group. ] 11. The electrophotographic photoconductor according to claim 10, wherein the photoconductive layer contains an azo compound represented by the following formula as a charge generating substance. Embedded image 12. The electrophotographic photoconductor according to claim 10, wherein the photoconductive layer contains an azo compound represented by the following formula as a charge generating substance. Embedded image 13. The electrophotographic photosensitive member according to claim 1, wherein the photosensitive layer comprises a single layer. 14. The method according to claim 1, wherein the photosensitive layer comprises a laminate in which a charge transport layer is provided on the charge generation layer.
11. The electrophotographic photosensitive member according to any one of 10. 15. The photosensitive layer comprises a laminate in which a charge generation layer is provided on a charge transport layer.
11. The electrophotographic photosensitive member according to any one of 10.