JP3482484B2 - Pigment mixture, method for producing the same, photosensitive layer coating solution containing the pigment mixture, and electrophotographic photoreceptor containing the pigment mixture - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pigment mixture, a method for producing the same, a photosensitive layer coating solution containing the pigment mixture, and an electrophotographic photoreceptor containing the pigment mixture. An electrophotographic photoreceptor having a high sensitivity in a wide wavelength range including an infrared light region, a photosensitive layer coating liquid for an electrophotographic photoreceptor having excellent viscosity characteristics and storage characteristics,
The present invention also relates to a pigment mixture that makes it possible and a method for producing the same.

[0002]

2. Description of the Related Art In recent years, the development of information processing system machines using electrophotography has been remarkable. In particular, an optical printer that converts information into a digital signal and records information by light has excellent print quality and reliability. This digital recording technology is applied not only to printers but also to ordinary copying machines, and so-called digital copying machines have been developed. Further, since various conventional information processing functions are added to a copying machine equipped with this digital recording technology in the conventional analog copying, it is expected that the demand will be further increased in the future.

As a light source for an optical printer, a semiconductor laser (LD) and a light emitting diode (LED) which are small in size, inexpensive and highly reliable are currently widely used. However,
The light emission wavelength of the LED that is currently widely used is 660 nm, while the light emission wavelength range of the LD is in the near infrared region. Therefore, development of an electrophotographic photoreceptor having high sensitivity in the visible light region to the near infrared light region is desired.

However, the photosensitive wavelength range of the electrophotographic photosensitive member is substantially determined by the photosensitive wavelength range of the charge generating substance (CGM) used in the photosensitive member. Therefore, many CGMs have been conventionally developed, but a single CGM having sufficiently high sensitivity in a wide photosensitive wavelength range from the visible light region to the near infrared light region has not yet been developed.

Therefore, conventionally, a CGM (short-wavelength CGM) having a high sensitivity to visible light and a CGM (long-wavelength CGM) having a sensitivity to near-infrared light are mixed to obtain a photosensitive member having a wide photosensitive wavelength range. Various designs have been attempted.
For example, (a) a trisazo pigment, (b) one or more kinds of perinone pigments and anzanthuron pigments, and (c) an electron-donating substance are contained, so that electrophotography having sensitivity to white light, gas laser, and LED. A printing plate for plate making (JP-A-3-146957) and an electrophotographic photoreceptor having sensitivity to white light and infrared laser by using a disazo pigment and oxotitanium phthalocyanine together (JP-A-3-196049). ), Or a mixture of trigonal selenium particles and phthalocyanine particles using a styrene-butadiene copolymer as a binder in a charge generation layer containing a mixed pigment, and having photosensitivity in the visible to infrared light region. Photoconductors (JP-A-3-225346) have been proposed. In addition, it has been announced that the photosensitivity of phthalocyanine is sensitized by mixing a perylene pigment and a β-type phthalocyanine pigment [Kawahara et al .: "Perylene pigment / phthalocyanine pigment intermolecular interaction and electrophotographic characteristics of an organic photoreceptor. »Proceedings of the 62nd Autumn Meeting of the Chemical Society of Japan
II P868 (1991); Kawahara et al., "Effect of Phthalocyanine Addition to Organic Single-Layer Photoreceptor Using Perylene Pigment", 68th
Proceedings of the Annual Meeting of the Electrophotographic Society of Japan P72-P75 (1
991)]. Further, a photoconductor having a low background potential and a residual potential has been proposed by combining a squarylium compound and an azo pigment having a work function larger than that of the squarylium compound (Japanese Patent Laid-Open No. 5-2828).
1771).

However, long-wavelength CGM generally has lower photosensitivity than short-wavelength CGM, which has sensitivity only in the visible light region, and when two kinds of CGMs are mixed, the long-wavelength CGM absorbs light in the long-wavelength CGM so that the sensitivity in the visible light region is short-wavelength CGM. It will be lower than when designed alone. Therefore, in the case of mixing CGM as in the above proposal, it is possible to widen the photosensitive wavelength range, but the sensitivity to light of each wavelength is lower than that of a photoreceptor designed by using each CGM alone, Sufficient characteristics cannot be obtained.

The azo pigment has been proposed as a pigment having high electrophotographic sensitivity. In particular, JP-A-53-
The pigment having a trisazo skeleton structure described in Japanese Patent No. 132347 can impart sensitivity to a long-wavelength light region, and has been put to practical use as a CGM for near infrared light. However, in order to cope with the downsizing and speeding up of information processing equipment in the future, higher sensitivity is required. Further, the trisazo pigment has a drawback that its charging property is deteriorated when it is exposed to ozone or NOx gas generated from a charger of a copying machine or a printer.

Further, the disazo pigment having a skeleton structure of fluorenone described in JP-A No. 54-22834 can have a particularly high sensitivity in the visible light region and has excellent gas resistance, so that it is visible light resistant. It has been put to practical use as a CGM for business. However, since this disazo pigment does not have sensitivity in the near infrared light region, it has a drawback that it cannot be applied to LD and LED light sources.

[0009]

In order to improve the above drawbacks, the present inventor has previously used a pigment mixture in which a sensitization phenomenon is exhibited by simultaneously pulverizing and mixing the above-mentioned trisazo pigment and disazo pigment. By doing each C
It has a higher sensitivity to visible light and near-infrared light than when a photoconductor is designed by using GM alone, and also has ozone and NO
An electrophotographic photosensitive member having little deterioration in charging characteristics due to x gas has been proposed (JP-A-6-49433).

However, in the mixed system of the above-mentioned trisazo pigment and disazo pigment, there is a problem that the expression of the sensitization phenomenon is greatly different depending on the dispersion medium used in the simultaneous mixing and pulverization. That is, there is a problem that sensitization occurs when dispersed in the solvent A and does not occur when dispersed in the solvent B.

[0011]

The present inventors SUMMARY OF THE INVENTION As a result of extensive studies to solve the above problems, when mixing and grinding the pigment, the ring-like ketone solvents and a mixed solvent of saturated hydrocarbon solvents, cyclic ketones A sensitizing effect can be obtained by simultaneously pulverizing and mixing one or more trisazo pigments and one or more disazo pigments in a mixed solvent of a system solvent and an ester solvent or a mixed solvent of a cyclic ketone solvent and a chain ketone solvent. The inventors have found that they are expressed and completed the present invention.

[0012] That is, according to the present invention, mixing of the ring-like ketone solvents and a mixed solvent of saturated hydrocarbon solvents, cyclic ketone solvents and mixed solvents or cyclic ketone solvent an ester solvent and a chain ketone solvent in a solvent, be one obtained by simultaneously pulverized and mixed one more trisazo pigment and one or more disazo pigment, the grinding and mixing
The processing consists of primary dispersion and secondary dispersion, and
Provided is a pigment mixture, which is characterized in that the secondary dispersion is performed in a mixed solvent .

Further, according to the present invention, in a preferred embodiment, the trisazo pigment is represented by the following general formula 1 and the disazo pigment is represented by the following general formula 2. A pigment mixture is provided.

[Chemical 1]

[Chemical 2] [However, in the general formulas 1 and 2 above, Ar ¹ , Ar ² , Ar
³ , Ar ⁴ and Ar ⁵ represent a coupler residue and may be the same or different. ]

Further, according to the present invention, in a preferred embodiment, the coupler residues Ar ¹ , Ar ² , Ar ³ , Ar ⁴ and Ar ⁵ represented by the general formulas 1 and / or 2 are represented by the following general formulas. A trisazo pigment and / or a disazo pigment represented by Chemical Formula 3 (provided that Ar ¹ , Ar ² , Ar ³ , Ar ⁴ and Ar ⁵ may be the same or different) are provided.

[Chemical 3] [However, in the above formula, X ¹ , Y ¹ and Z respectively represent the following. ^{X 1: -OH, -N (R} 1) (R 2) or -NHSO ₂ -R
³ . (R ¹ and R ² represent a hydrogen atom, an acyl group 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 atom A halogen atom, a substituted or unsubstituted alkyl group, an alkoxy group, a carboxy group, a sulfone group, a benzimidazolyl group, a substituted or unsubstituted sulfamoyl group, a substituted or unsubstituted allofanoyl group or -CON (R ⁴ ) (Y ² ) Represents. {R ⁴ represents a hydrogen atom, an alkyl group or a substituted product thereof, a phenyl group or a substituted product thereof, and Y ² represents a hydrocarbon ring group or a substituted product thereof, a heterocyclic group or a substituted product thereof, or -N =
C (R ⁵ ) (R ⁶ ) (wherein R ⁵ is 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, and R ⁶ is a hydrogen atom, an alkyl group or a substituted product thereof. Or a phenyl group or a substituted form thereof, or R ⁵ and R ⁶ may form a ring together with the carbon atom bonded to them. } Z: Hydrocarbon ring group or a substituted body thereof, or heterocyclic group or a substituted body thereof. ] Further, the coupler residues Ar ¹ , Ar ² , Ar ³ and A represented by the general formulas 1 and / or 2 are represented.
r ⁴ and Ar ⁵ are trisazo pigments and / or disazo pigments represented by the following general formula 4 (provided that Ar ¹ , Ar ² , Ar
³ , Ar ⁴ and Ar ⁵ may be the same or different, respectively.)
Is provided.

[Chemical 4] [However, in the above formula, R ⁷ , R ⁸ , Y ¹ and n respectively represent the following. n: An integer of 1 to 4. R ⁷ : hydrogen atom, substituted or unsubstituted alkyl group or substituted or unsubstituted aryl group. R ⁸ : hydrogen atom, substituted or unsubstituted alkyl group, substituted or unsubstituted alkoxy group, substituted or unsubstituted alkylsulfonyl group, substituted or unsubstituted alkylmercapto group, halogen atom, substituted or unsubstituted aryl group Represents a substituted or unsubstituted acyl group, cyano group, nitro group or substituted or unsubstituted amino group, and when n is an integer of 2 to 4, R ⁸ may be the same or different. Y ¹ : Same as in General Formula 3. ]

Furthermore, according to the present invention, one or more trisazo pigments and one or more disazo pigments are dissolved in a cyclic ketone system.
Solvent and mixed solvent of saturated hydrocarbon solvent, cyclic ketone solvent
And ester solvent mixed solvent or cyclic ketone solvent and chain
Simultaneously pulverized and mixed in a mixed solvent of Jo ketone solvent
A method for producing a pigment mixture, wherein the pulverizing and mixing treatment is the primary
Consists of dispersion and quadratic dispersion,
Method for producing a pigment mixture which comprises carrying out in a mixed solvent Ru are provided also.

Further, according to the present invention, there is provided a photosensitive layer coating liquid containing a pigment mixture as an active ingredient by simultaneously pulverizing and mixing in a solvent having poor dispersibility or the mixed solvent. To be done.

Further, according to the present invention, in an electrophotographic photoreceptor having a photoconductive layer formed on a conductive support, at least one layer forming the photoconductive layer contains the pigment mixture. A featured electrophotographic photoreceptor is provided.

[0018]

In DETAILED DESCRIPTION OF THE INVENTION The present invention, ring-shaped ketone solvents and a mixed solvent of saturated hydrocarbon solvents, cyclic ketone solvents and ester-based mixed solvent, or cyclic ketone solvent and a chain ketone solvent solvent It is carried out in a mixed solvent. The sensitizing effect is exhibited only when the pigment is dispersed in these solvents, and the sensitizing phenomenon does not occur when the pigment is dispersed in any other solvent.

The pigment mixture of the present invention has a high sensitivity to visible light together with a trisazo pigment (preferably a compound represented by the general formula 1) having sensitivity to light having a length of 700 nm or longer in the above-mentioned solvent. Since it was prepared by simultaneously pulverizing with a disazo pigment (preferably the compound represented by the above-mentioned general formula 2), it is possible to use the individual pigments alone without decreasing the sensitivity to visible light. Is more sensitive to visible light and near-infrared light, and deterioration of the charging characteristics due to ozone or NOx gas is less than that of the case of designing. This sensitizing effect will be clarified in Examples described later, but the trisazo pigment and the disazo pigment are mixed and pulverized by simultaneously applying mechanical energy in the above-mentioned solvent, whereby the sensitivity is remarkably higher than in the case of each pigment alone. Because it is sensitized,
This is different from the previously proposed mixing effect of the combination of pigments.

The solvent used in the simultaneous pulverization and mixing of the trisazo pigment and the disazo pigment in the present invention will be described in more detail. By using at least one solvent selected from a cyclic ketone solvent, a cyclic ether solvent and a chlorine solvent, the resulting pigment mixture develops a sensitization phenomenon and an electrophotographic photosensitive material containing the pigment mixture. The body becomes extremely sensitive.

The reason for this is not clear, but if the pigment is dispersed in a solvent selected from, for example, a cyclic ketone solvent, a cyclic ether solvent, and a chlorine solvent, the secondary pigments are mixed in a well-mixed state. Whereas particles are formed,
It is considered that each pigment independently forms secondary particles when dispersed in a solvent other than the above.
That is, it is considered that the expression of the sensitization phenomenon is influenced by the difference in the contact state of the pigment.

Considering the characteristics of the photosensitive layer coating liquid comprehensively, the above solvents are desired to be improved in the following points. That is, when a cyclic ketone solvent is used, the pigment that was stably present as secondary particles decomposes into primary particles over time, and the liquid physical properties change significantly (in particular, the viscosity increases). However, it may be difficult to form a uniform coating film. Further, with respect to the cyclic ether type solvent, if tetrahydrofuran is used as a dispersion medium and dispersion is carried out for a long time, there is a problem that the sensitivity is lowered. This is because the crystal type of the trisazo pigment changes with tetrahydrofuran. Other cyclic ether solvents have no problem of change in crystal system, but dioxane has a safety problem as a carcinogen, and tetrahydropyran, 2-methyltetrahydrofuran, etc. are very expensive. Have. Further, the chlorine-based solvent has problems of carcinogenicity and environmental pollution.

In order to improve this point, the present invention
Te as the solvent, to use a mixed solvent or a cyclic ketone solvent and a chain ketone mixed solvent of solvents of ring-like ketone solvents and ester solvents. By using these solvents, it is possible to obtain a photosensitive layer coating solution which exhibits a sensitizing effect and has good dispersion stability.

The reason for this is not clear, but it is estimated as follows. That is, when using the above SL cyclic ketone solvents and a mixed solvent of saturated hydrocarbon solvents, cyclic ketone solvents and ester-based mixed solvent, or cyclic ketone mixed solvent of a solvent and a chain ketone solvent solvent It is considered that the cyclic ketone solvent contributes to the development of the sensitization phenomenon, and the saturated hydrocarbon solvent, the ester solvent, and the chain ketone solvent contribute to good dispersion stability.

The electrophotographic photosensitive member of the present invention prepared by coating the photosensitive layer coating liquid having good dispersion stability is
It has higher sensitivity to visible light and near-infrared light than when a photoreceptor is designed by using each pigment alone without lowering the sensitivity to visible light.

The mixing ratio of the trisazo pigment (preferably the compound represented by the chemical formula 1) and the disazo pigment (preferably the compound represented by the chemical formula 2) used in the present invention depends on the kind of the pigment to be mixed. The optimum value can be individually selected in consideration of the required properties (sensitivity, charging property, gas resistance), but generally 0.01 by weight ratio Trisazo pigment (Chemical formula 1) / {Trisazo pigment (Chemical formula 1) + Disazo pigment (Chemical formula 2)} ≦ 0.99 is preferable. When it is lower than 0.01, the sensitivity sensitizing effect is reduced, and when it is higher than 0.99, the improvement in gas resistance is reduced. Furthermore, considering the uniformity of spectral sensitivity from the visible light wavelength region to the near infrared light wavelength region, 0.1 ≦ trisazo pigment (Chemical formula 1) / {trisazo pigment (Chemical formula 1) + disazo pigment (Chemical formula 2)} The range of ≦ 0.9 is desirable.

The dispersion method of the trisazo pigment (Chemical formula 1) and the disazo pigment (Chemical formula 2) includes a ball mill, a vibration mill, and
Disk vibration mill, attritor, sand mill, paint shaker, jet mill, ultrasonic dispersion, etc.
Any pulverizing and mixing means that gives mechanical energy such as shearing, grinding, rubbing, stretching, impact, vibration, etc. can be used. Further, it is preferable that predetermined amounts of the trisazo pigment and the disazo pigment are put in the same container, and at the same time, the above mechanical energy is applied to mix and pulverize them for dispersion.

Examples of the solvent used for dispersion include the following. As the solvent for the cyclic ketone, cyclohexanone, cyclopentanone, 2-methylcyclohexanone, etc. is Ru mentioned.

[0029]

As the solvent when the mixed solvent is used,
The following are listed . The saturated hydrocarbon solvents, cyclohexane, normal hexane, normal heptane and the like. Examples of the ester solvent include ethyl acetate, methyl acetate, butyl acetate and the like. Examples of the chain ketone solvent include acetone, 2-butanone, 4-methyl-2-pentanone and the like.

The trisazo pigment represented by the following general formula 1 used in the present invention is disclosed in JP-A-53-132347, and the disazo pigment represented by the following general formula 2 is disclosed in JP-A-54-22834. It can be manufactured by the method described in the publication.

[Chemical 1]

[Chemical 2] [However, in the general formulas 1 and 2 above, Ar ¹ , Ar ² , Ar
³ , Ar ⁴ and Ar ⁵ represent a coupler residue and may be the same or different. ]

Ar ¹ , Ar ² , Ar ³ , Ar ⁴ and A
r ⁵ represents a coupler residue selected from the group represented by the following general formula 3.

[Chemical 3] [However, in the above formula, X ¹ , Y ¹ and Z respectively represent the following. ^{X 1: -OH, -N (R} 1) (R 2) or -NHSO ₂ -R
³ . (R ¹ and R ² represent a hydrogen atom, an acyl group 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 atom A halogen atom, a substituted or unsubstituted alkyl group, an alkoxy group, a carboxy group, a sulfone group, a benzimidazolyl group, a substituted or unsubstituted sulfamoyl group, a substituted or unsubstituted allofanoyl group or -CON (R ⁴ ) (Y ² ) Represents. {R ⁴ represents a hydrogen atom, an alkyl group or a substituted product thereof, or a phenyl group or a substituted product thereof, Y ² is a hydrocarbon ring group or a substituted product thereof, a heterocyclic group or a substituted product thereof, or -N = C
(R ⁵ ) (R ⁶ ) (wherein R ⁵ is 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, and R ⁶ is a hydrogen atom, an alkyl group or a substituted product thereof. Or a phenyl group or a substituted form thereof, or R ⁵ and R ⁶ may form a ring together with the carbon atom bonded to them. } Z: Hydrocarbon ring group or a substituted body thereof, or heterocyclic group or a substituted body thereof. ]

Further, Ar ¹ , Ar ² , Ar ³ , Ar ⁴ and A
r ⁵ represents a coupler residue selected from the group represented by the following general formula 4.

[Chemical 4] [However, in the above formula, R ⁷ , R ⁸ , Y ¹ and n respectively represent the following. n: An integer of 1 to 4. R ⁷ : hydrogen atom, substituted or unsubstituted alkyl group or substituted or unsubstituted aryl group. R ⁸ : hydrogen atom, substituted or unsubstituted alkyl group, substituted or unsubstituted alkoxy group, substituted or unsubstituted alkylsulfonyl group, substituted or unsubstituted alkylmercapto group, halogen atom, substituted or unsubstituted aryl group Represents a substituted or unsubstituted acyl group, cyano group, nitro group or substituted or unsubstituted amino group, and when n is an integer of 2 to 4, R ⁸ may be the same or different. Y ¹ : Same as in General Formula 3. ]

Further, Ar ¹ , Ar ² , Ar ³ , Ar ⁴ and A
r ⁵ represents a coupler residue selected from the group represented by the following general formulas 5 to 9.

[Chemical 5] (In the above formula, R ⁹ represents a substituted or unsubstituted hydrocarbon group.)

[Chemical 6] (In the above formula, R ⁹ represents a substituted or unsubstituted hydrocarbon group.)

[0035]

[Chemical 7] (In the above formula, R ¹⁰ represents an alkyl group, a carbamoyl group, a carboxyl group or an ester thereof, and Ar ¹¹ represents a substituted or unsubstituted aromatic hydrocarbon group.)

[0036]

[Chemical 8] (In the above formula, X ² represents a divalent group of an aromatic hydrocarbon or a divalent group of a heterocycle.)

[Chemical 9] (In the above formula, X ² represents a divalent group of an aromatic hydrocarbon or a divalent group of a heterocycle.)

Specific examples of couplers for azo pigments used in the present invention, that is, Ar ¹ -H, Ar ² -H, Ar ^3-.
Specific examples of H, Ar ⁴ -H and Ar ⁵ -H are shown in Tables 1 to 14.

[0038]

[Table 1- (1)]

[0039]

[Table 1- (2)]

[0040]

[Table 1- (3)]

[0041]

[Table 2- (1)]

[0042]

[Table 2- (2)]

[0043]

[Table 3- (1)]

[0044]

[Table 3- (2)]

[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- (1)]

[0054]

[Table 12- (2)]

[0055]

[Table 12- (3)]

[0056]

[Table 13- (1)]

[0057]

[Table 13- (2)]

[0058]

[Table 13- (3)]

[0059]

[Table 14- (1)]

[0060]

[Table 14- (2)]

[0061]

[Table 15]

[0062]

[Table 16]

The photosensitive layer of the electrophotographic photosensitive member of the present invention can be of a dispersion type or a function separation type by combining a charge generating substance and a charge transporting substance. In the case of a dispersion type layer structure, a photosensitive layer in which a charge generating substance and a charge transporting substance are dispersed in a binder is provided on a conductive substrate. In the case of the function separation type, a charge generating layer containing a charge generating substance and a binder is formed on a substrate, and a charge transporting layer containing a charge transporting substance and a binder is formed thereon. The charge transport layers may be laminated in reverse. In the case of function separation type,
A charge transport material may be contained in the charge generation layer.

An intermediate layer may be provided between the photosensitive layer and the substrate to improve the adhesiveness and the charge blocking property. Further, in order to improve mechanical durability such as abrasion resistance, a protective layer may be provided on the photosensitive layer. As the binder used in the formation of the charge generation layer, the charge transport layer and the dispersion type photosensitive layer, any conventionally known binder having a good insulating property can be used, and there is no particular limitation. . 1
For example, polycarbonate (bisphenol A type, bisphenol Z type), polyester, methacrylic resin, acrylic resin, polyethylene, polyvinyl chloride, polyvinyl acetate, polystyrene, phenol resin,
Epoxy resin, polyurethane, polyvinylidene chloride, alkyd resin, silicone resin, polyvinyl carbazole, polyvinyl butyral, polyvinyl carbazole,
Polyvinyl butyral, polyvinyl formal, polyarylate, polyacrylamide, polyamide, phenoxy resin and the like are used. These binders are used alone or 2
It can be used as a mixture of two or more species.

When a photoconductor is prepared by using the above-mentioned layer structure and substances, the film thickness and the ratio of substances have preferable ranges. In the case of stacking substrate / charge generation layer / charge transport layer,
In the charge generation layer, the ratio of the charge generation substance to the binder is preferably 20% by weight or more and the film thickness is preferably 0.01 to 5 μm. In the charge transport layer, the ratio of the charge transport material to the binder is 20 to 200% by weight, and the film thickness is 5 to 100 μm.
It is preferably m. In the case of stacking substrate / charge transport layer / charge generation layer, in the charge transport layer, the ratio of the charge transport material to the binder is 20 to 200% by weight, and the film thickness is 5
It is preferably set to -100 μm. The charge generation layer preferably contains the charge generation substance in an amount of 20% by weight or more based on the binder. Furthermore, it is preferable to include a charge transporting substance in the charge generating layer, and by containing it, it is effective in suppressing the residual potential and improving the sensitivity. In this case, the charge transport material is preferably contained in the binder in an amount of 20 to 200% by weight.

In the case of a so-called dispersion type photoreceptor in which a charge generating substance and a charge transporting substance are dispersed in a binder resin, the binder resin is mixed in the photosensitive layer as the charge generating substance. The proportion of pigment is 5 to 95% by weight, and the film thickness is 10
100 μm is preferable. In that case, the ratio of the charge transport material to the binder resin is preferably 30 to 200% by weight.

Further, in these photosensitive layers, both dispersion type and function separation type, for the purpose of improving charging property and gas resistance,
So-called antioxidants such as phenol compounds, hydroquinone compounds, hindered phenol compounds, hindered amine compounds, and compounds in which hindered amine and hindered phenol are present in the same molecule can be added.

In the present invention, the conductive substrate has a volume resistance of 10 ¹⁰ Ω · cm or less, for example, aluminum, nickel, chromium, nichrome, copper,
A metal such as silver, gold, or platinum, or a metal oxide such as indium oxide or tin oxide, copper iodide, or the like is coated on a film or a cylindrical drum, a belt-shaped film, paper, or the like by an evaporation or a sputtering method. Or plates, belts of aluminum, aluminum alloy, nickel, stainless steel, etc. I. , I. I. It is possible to use a raw pipe which has been subjected to a surface treatment by cutting superfinishing, polishing or the like after being made into a raw pipe by a method such as extrusion, drawing or the like. Also,
A conductive powder such as carbon black, indium oxide, or tin oxide may be dispersed in an appropriate resin and coated on plastic or the like.

The charge transport material includes a hole transport material and an electron transport material. As the hole transport material, for example, poly-N
-Carbazole and its derivatives, poly-γ-carbazolylethylglutamate and its derivatives, pyrene-formaldehyde condensate and its derivatives, polyvinylpyrene,
There are polyvinylphenanthrene, oxazole derivatives, imidazole derivatives, triphenylamine derivatives, and compounds represented by the following general formula.

(1) (described in JP-A-55-154955 and JP-A-55-156954)

[Chemical 10] [In the formula, R ¹ represents a methyl group, an ethyl group, a 2-hydroxyethyl group or a 2-chloroethyl group, R ² represents a methyl group, an ethyl group, a benzyl group or a phenyl group, and R ³
Represents a hydrogen atom, a chlorine atom, a bromine atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, a dialkylamino group or a nitro group. ]

(2) (described in JP-A-55-52063)

[Chemical 11] [In the formula, Ar represents a naphthalene ring, an anthracene ring, a styryl ring and a substitution product thereof, a pyridine ring, a furan ring or a thiophene ring, and R represents an alkyl group or a benzyl group. ]

(3) (described in JP-A-56-81850)

[Chemical 12] [In the formula, R ¹ represents an alkyl group, a benzyl group, a phenyl group or a naphthyl group, and R ² represents a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, an alkoxy group having 1 to 3 carbon atoms, a dialkylamino group, a dialkylamino group, It represents an aralkylamino group or a diarylamino group, n represents an integer of 1 to 4, and when n is 2 or more, R ² may be the same or different. R ³ represents a hydrogen atom or a methoxy group. ]

(4) (described in JP-B-51-10983)

[Chemical 13] [In the formula, R ¹ represents an alkyl group having 1 to 11 carbon atoms, a substituted or unsubstituted phenyl group or a heterocyclic group, and R ² , R ³
May be the same or different and each represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, a hydroxyalkyl group, a chloroalkyl group or a substituted or unsubstituted aralkyl group, and R ² and R ³ are bonded to each other. And may form a heterocycle containing nitrogen. R ^{4 s} may be the same or different and each represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group or a halogen atom. ]

(5) (described in JP-A-51-94829)

[Chemical 14] [In the formula, R represents a hydrogen atom or a halogen atom, and Ar represents a substituted or unsubstituted phenyl group, naphthyl group, anthryl group or carbazolyl group. ]

(6) (described in JP-A-52-128373)

[Chemical 15] [In the formula, R ¹ represents a hydrogen atom, a halogen atom, a cyano group, an alkoxy group having 1 to 4 carbon atoms or an alkyl group having 1 to 4 carbon atoms, and Ar is

[Chemical 16] R ² represents an alkyl group having 1 to 4 carbon atoms, R ³ represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 4 carbon atoms,
Represents an alkoxy group or a dialkylamino group having 1 to 4 carbon atoms, n is 1 or 2, and when n is 2, R ³ may be the same or different, R ⁴ and R ⁵ are hydrogen atoms, carbon It represents a substituted or unsubstituted alkyl group of the formulas 1 to 4 or a substituted or unsubstituted benzyl group. ]

(7) (described in JP-A-56-29245)

[Chemical 17] [In the formula, R is 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, and these substituents are dialkylamino groups. A group selected from the group consisting of an alkyl group, an alkoxy group, a carboxy group or an ester thereof, a halogen atom, a cyano group, an aralkylamino group, an N-alkyl-N-aralkylamino group, an amino group, a nitro group and an acetylamino group. Represents ]

(8) (described in JP-A-58-58552)

[Chemical 18] [Wherein R ¹ represents a lower alkyl group, a substituted or unsubstituted phenyl group, or a benzyl group, R ² represents a hydrogen atom,
It represents a lower alkyl group, a lower alkoxy group, a halogen atom, a nitro group, an amino group or an amino group substituted with a lower alkyl group or a benzyl group, and n represents an integer of 1 or 2. ]

(9) (described in JP-A-57-73075)

[Chemical 19] [Wherein R ¹ represents a hydrogen atom, an alkyl group, an alkoxy group or a halogen atom, R ² and R ³ represent an alkyl group, a substituted or unsubstituted aralkyl group or a substituted or unsubstituted aryl group, and R ⁴ represents Represents a hydrogen atom, a lower alkyl group or a substituted or unsubstituted phenyl group, and
Ar represents a substituted or unsubstituted phenyl group or naphthyl group. ]

(10) (described in JP-A-58-198043)

[Chemical 20] [In the formula, n is an integer of 0 or 1, R ¹ represents a hydrogen atom, an alkyl group or a substituted or unsubstituted phenyl group, and Ar
¹ represents a substituted or unsubstituted aryl group, R ⁵ represents an alkyl group containing a substituted alkyl group, or a substituted or unsubstituted aryl group, and A represents

[Chemical 21] 9-anthryl group or substituted or unsubstituted carbazoli
Represents a radical, where R²Is a hydrogen atom, alkyl group,
Coxy group, halogen atom or A group or a substituted or unsubstituted aryl group, R³Over
And R^FourR may be the same or different and R^FourForms a ring
, And m is an integer of 0, 1, 2, or 3.
So, when m is 2 or more, R²Can be the same or different
Yes. Also, when n is 0, A and R¹Together form a ring
May be. ]

(11) (described in JP-A-49-105537)

[Chemical formula 22] [In the formula, R ¹ , R ² and R ³ represent a hydrogen atom, a lower alkyl group, a lower alkoxy group, a dialkylamino group or a halogen atom, and n represents 0 or 1. ]

(12) (described in JP-A-52-139066)

[Chemical formula 23] [In the formula, R ¹ and R ² represent an alkyl group containing a substituted alkyl group or a substituted or unsubstituted aryl group, and A represents a substituted amino group, a substituted or unsubstituted aryl group or an allyl group. ]

(13) (described in JP-A-52-139065)

[Chemical formula 24] [In the formula, X represents a hydrogen atom, a lower alkyl group or a halogen atom, R represents an alkyl group containing a substituted alkyl group, or a substituted or unsubstituted aryl group, and A represents a substituted amino group or a substituted or unsubstituted aryl group. Represents an aryl group. ]

(14) (described in JP-B-58-32372)

[Chemical 25] [In the formula, R ¹ represents a lower alkyl group, a lower alkoxy group or a halogen atom, n represents an integer of 0 to 4, R ² ,
R ^{3 s} may be the same or different and each represents a hydrogen atom, a lower alkyl group, a lower alkoxy group or a halogen atom. ]

(15) (described in JP-A-2-178669)

[Chemical formula 26] [Wherein R ¹ , R ³ and R ⁴ are hydrogen atom, amino group, alkoxy group, thioalkoxy group, aryloxy group, methylenedioxy group, substituted or unsubstituted alkyl group, halogen atom or substituted or unsubstituted The aryl group of R
² represents a hydrogen atom, an alkoxy group, a substituted or unsubstituted alkyl group or a halogen atom. However, R ¹ , R ² , R
Except when ³ and R ⁴ are all hydrogen atoms. Also,
k, l, m and n are integers of ¹ , ² , 3 or 4, and when each is an integer of 2, 3 or 4, R ¹ , R ² , R ³
And R ⁴ may be the same or different. ]

(16) (described in JP-A-3-285960)

[Chemical 27] [In the formula, Ar represents a condensed polycyclic hydrocarbon group having 18 or less carbon atoms, and R ¹ and R ² are a hydrogen atom, a halogen atom,
It represents a substituted or unsubstituted alkyl group, an alkoxy group, or a substituted or unsubstituted phenyl group, which may be the same or different. ]

(17) (described in Japanese Patent Application No. 62-98394)

Embedded image A-CH = CH-Ar-CH = CH-A [In the formula, Ar is a substituted or unsubstituted aromatic hydrocarbon group.
And A is Represents a hydrogen group, R¹And R²Is a substituted or unsubstituted al
A killed group, or a substituted or unsubstituted aryl group
,)). ]

(18) (described in JP-A-4-230764)

[Chemical 29] [In the formula, Ar represents an aromatic hydrocarbon group, and R represents a hydrogen atom, a substituted or unsubstituted alkyl group or an aryl group, respectively. n is 0 or 1, m is 1 or 2, and n =
When 0 and m = 1, Ar and R may jointly form a ring. ]

Examples of the compound represented by the general formula 10 include 9-ethylcarbazole-3-aldehyde-1-
Methyl-1-phenylhydrazone, 9-ethylcarbazole-3-aldehyde-1-benzyl-1-phenylhydrazone, 9-ethylcarbazole-3-aldehyde-
1,1-diphenylhydrazone and the like. The compound represented by the general formula 11 includes, for example, 4-diethylaminostyryl-β-aldehyde-1-methyl-1-
There are phenylhydrazone, 4-methoxynaphthalene-1-aldehyde-1-benzil-1-phenylhydrazone and the like.

Examples of the compound represented by the general formula 12 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, 4-
Diphenylaminobenzaldehyde-1-benzyl-1
-Phenylhydrazone, 4-dibenzylaminobenzaldehyde-1,1-diphenylhydrazone and the like.
Further, the compound represented by the general formula 13 includes, for example,
1,1-bis (4-dibenzylaminophenyl) propane, tris (4-diethylaminophenyl) methane,
1,1-bis (4-dibenzylaminophenyl) propane, 2,2'-dimethyl-4,4'-bis (diethylamino) -triphenylmethane and the like.

Examples of the compound represented by the general formula 14 include 9- (4-diethylaminostyryl) anthracene and 9-bromo-10- (4-diethylaminostyryl) anthracene. In addition, examples of the compound represented by the general formula 15 include 9- (4-dimethylaminobenzylidene) fluorene and 3- (9-fluorenylidene) -9-ethylcarbazole. Further, the compound represented by the general formula 17 includes, for example, 1,2-
Bis (4-diethylaminostyryl) benzene, 1,2
-Bis (2,4-dimethoxystyryl) benzene and the like.

Examples of the compound represented by the general formula 18 include 3-styryl-9-ethylcarbazole and 3-
(4-methoxystyryl) -9-ethylcarbazole and the like. In addition, the compound represented by the general formula 19 includes, for example, 4-diphenylaminostilbene, 4-dibenzylaminostilbene, 4-ditolylaminostilbene, 1- (4-diphenylaminostyryl) naphthalene, 1- (4 -Diethylaminostyryl) naphthalene and the like.

The compound represented by the general formula 20 includes, for example, 4'-diphenylamino-α-phenylstilbene, 4'-bis (4-methylphenyl) amino-α-phenylstilbene and the like. Further, the compound represented by the general formula 22 includes, for example, 1-phenyl-3- (4
-Diethylaminostyryl) -5- (4-diethylaminophenyl) pyrazoline, 1-phenyl-3- (4-dimethylaminostyryl) -5- (4-dimethylaminophenyl) pyrazoline and the like.

Examples of the compound represented by the general formula 23 include 2,5-bis (4-diethylaminophenyl)-
1,3,4-oxadiazole, 2-N, N-diphenylamino-5- (4-diethylaminophenyl) -1,
3,4-oxadiazole, 2- (4-dimethylaminophenyl) -5- (4-diethylaminophenyl) 1,
3,4-oxadiazole and the like. The compound represented by the general formula 24 includes, for example, 2-N, N-diphenylamino-5- (N-ethylcarbazole-3-
Yl) -1,3,4-oxadiazole, 2- (4-diethylaminophenyl) -5- (N-ethylcarbazol-3-yl) -1,3,4-oxadiazole and the like.

Examples of the benzidine compound represented by the general formula 25 include N, N'-diphenyl-N, N'-bis (3-methylphenyl)-[1,1'-biphenyl].
-4,4'-diamine, 3,3'-dimethyl-N, N,
N ', N'-tetrakis (4-methylphenyl)-
Examples include [1,1′-biphenyl] -4,4′-diamine. Further, the biphenylamine compound represented by the general formula 26 includes, for example, 4′-methoxy-N, N-diphenyl- [1,1′-biphenyl] -4-amine, 4 ′.
-Methyl-N, N-bis (4-methylphenyl)-
[1,1'-biphenyl] -4-amine, 4'-methoxy-N, N-bis (4-methylphenyl)-[1,1 '
-Biphenyl] -4-amine and the like.

Examples of the triarylamine compound represented by the general formula 27 include 1-diphenylaminopyrene and 1-di (p-tolylamino) pyrene. The diolefin aromatic compound represented by the general formula 28 includes, for example, 1,4-bis (4-diphenylaminostyryl) benzene and 1,4-bis [4-di (p-tolyl) aminostyryl]. For example, benzene. Further, the styrylpyrene compound represented by the general formula 29 includes, for example, 1- (4-diphenylaminostyryl) pyrene, 1
-[4-di (p-tolyl) aminostyryl] pyrene and the like.

Examples of the electron-transporting substance include chloranil, bromanil, tetracinoethylene, tetracyanoquinodimethane, 2,4,7-trinitro-9-fluorenone, 2,4,5,7-tetranitro-9-. Fluorenone, 2,4,5,7-tetranitroxanthone,
2,4,8-trinitrothioxanthone, 2,6,8-
Trinitro-indeno 4H-indeno [1,2-b] thiophen-4-one, 1,3,7-trinitrodibenzothiophene-5,5-dioxide, 3,5-dimethyl-3 ', 5'-di Examples include -tert-butyl-4,4'-diphenoquinone. These charge transport materials may be used alone or in combination of two or more.

[0097]

EXAMPLES The present invention will be described below with reference to examples, but the embodiments of the present invention are not limited thereby. Incidentally, the real
Examples 1-1 to 13 and Examples 2-1 to 3 are reference examples.
It

Specific examples of the pigments used in Examples are No. Is
The following azo structural component No. And the coupler Nos. In Tables 1 to 16. The pigments are indicated by the combination of the respective numbers. Example: A-1 (the one having the No. 1 coupler attached to the central skeleton of A) B-1 (the one having the No. 1 coupler attached to the central skeleton of B. Symmetrical pigment) B-1 and 2 (B No. 1 and No. 2 couplers attached to the central skeleton of Asymmetric pigment

Azo component structure No.

[Chemical 30]

[Chemical 31]

Example 1-1 The following pigments, resins and solvents were filled in half with a volume of φ10 mm PSZ (partially stabilized zirconia) balls by φ15.
Place in a cm glass pot for 5 days ball milling (1
Next dispersion) was performed. Trisazo pigment 5.0 g (Exemplified compound No. A-70) Disazo pigment 5.0 g (Exemplified compound No. B-17, 24) Cyclohexanone 390 g

Then, 600 g of cyclohexanone was added and ball milling was carried out for 1 day to prepare a coating solution for the charge generation layer.

The above charge generation layer coating liquid is applied to a thickness of 0.2 m.
m aluminum plate (JIS 1080) with a doctor blade having a gap of 50 μm, and then 120
After drying at 10 ° C. for 10 minutes, a charge generation layer having a thickness of about 0.2 μm was formed.

Next, a charge transport layer coating solution prepared by stirring and dissolving the following compounds was applied onto the charge generating layer with a doctor blade and dried at 120 ° C. for 20 minutes to give a thickness of about A 28 μm charge transport layer was formed to prepare a photoreceptor.

[0104] (Composition of charge transport layer coating liquid)     9 parts by weight of charge transport material represented by the following structural formula 32     Bisphenol Z type polycarbonate resin 10 parts by weight       (TS2050: manufactured by Teijin Chemicals; viscosity average molecular weight 40,000)     Silicone oil (KF50: manufactured by Shin-Etsu Silicone) 0.002 parts by weight     86 parts by weight of dichloromethane

[0105]

[Chemical 32]

Comparative Example 1-1 5.0 g of the trisazo pigment of Example 1 and 5.
A photoconductor was prepared in the same manner as in Example 1 except that 10.0 g of trisazo pigment was used instead of 0 g.

Comparative Example 1-2 A photoreceptor was prepared in the same manner as in Example 1 except that 10.0 g of the disazo pigment was used instead of 5.0 g of the trisazo pigment and 5.0 g of the disazo pigment of Example 1-1. It was created.

Examples 1-2 to 1-9 and Comparative Examples 1-3 to
1-6 Photosensitization was carried out in the same manner as in Example 1-1, except that the solvent used in the primary dispersion and the secondary dispersion was changed as shown in Table 17 when the coating solution for the charge generation layer in Example 1-1 was prepared. Created the body.

[0109]

[Table 17]

Example 1-10 The following pigments and solvents were placed in a φ15 cm glass pot half-filled with φ10 mm PSZ (partially stabilized zirconia) balls, and ball milling (primary dispersion) was carried out for 5 days. Trisazo pigment 5.0 g (Exemplified compound No. A-70) Disazo pigment 5.0 g (Exemplified compound No. B-17) Cyclohexanone 390 g

Thereafter, 600 g of cyclohexanone was added, and ball milling (secondary dispersion) was performed for 1 day to prepare a charge generation layer coating solution.

The above charge generation layer coating liquid was applied to a thickness of 0.2 m.
m aluminum plate (JIS 1080) with a doctor blade having a gap of 50 μm, and then 120
After drying at 10 ° C. for 10 minutes, a charge generation layer having a thickness of about 0.2 μm was formed.

Next, a charge transport layer coating solution prepared by stirring and dissolving the following compounds was applied onto the charge generating layer with a doctor blade and dried at 120 ° C. for 20 minutes to give a thickness of about A 28 μm charge transport layer was formed to prepare a photoreceptor.

[0114] (Composition of charge transport layer coating liquid)     7 parts by weight of a charge transport material represented by the following structural formula 33     Bisphenol A type polycarbonate resin 10 parts by weight       (K1300: manufactured by Teijin Chemicals)     Silicone oil (KF50: manufactured by Shin-Etsu Silicone) 0.002 parts by weight     86 parts by weight of dichloromethane

[0115]

[Chemical 33]

Comparative Example 1-7 In the same manner as in Example 1-10 except that 5.0 g of the trisazo pigment and 5.0 g of the disazo pigment of Example 1-10 were replaced with 10.0 g of the trisazo pigment. A photoconductor was created.

Comparative Example 1-8 The same procedure as in Example 1-10 except that 10.0 g of a disazo pigment was used in place of 5.0 g of the trisazo pigment and 5.0 g of the disazo pigment of Example 1-10. A photoconductor was created.

Examples 1-11-1-13 and Comparative Example 1-
9 A photoconductor was prepared in the same manner as in Example 1-10, except that the solvents used in the primary dispersion and the secondary dispersion were changed as shown in Table 18 when the coating solution for the charge generation layer in Example 1-10 was prepared. Created.

[0119]

[Table 18]

The photoconductor thus prepared was charged in a dynamic mode with an electrophotographic characteristic measuring apparatus EPA8100 (manufactured by Kawaguchi Electric Co., Ltd.) in a dynamic mode, and the photoconductor was charged at -800 V.
780n light from a tungsten lamp with a color temperature of 2856K
The photosensitivity was measured by irradiating through a bandpass filter of m (half-width of 13 nm). The results are shown in Table 19. The photosensitivity S _800-100 (V · cm ² / μJ) has a surface potential of −80.
The exposure amount required to attenuate from 0V to -100V is E
(ΜJ / cm ² ), and is determined by S _800-100 = 700 / E.

[0121]

[Table 19]

From Table 19, it can be seen that, in systems in which cyclohexanone of Examples 1-1, 1-10 and Comparative Examples 1-1, 1-2, 1-7, 1-8 is used as a dispersion medium, trisazo pigments and disazo pigments are prepared. Comparing the mixed system with the single system of the trisazo pigment and the disazo pigment, it can be seen that the mixed system has higher photosensitivity and is sensitized as compared with the single system. In addition, Example 1-1
~ 1-10, 1-11 to 1-13, Comparative Examples 1-3 to 1-
From 6 to 1-9, when a cyclic ketone solvent, a cyclic ether solvent, or a chlorine solvent is used as a dispersion medium, sensitization occurs and the sensitivity is high, whereas when other solvents are used, the trisazo pigment alone is used. It can be seen that it shows only sensitivity equal to or lower than.

Example 2-1 (Preparation of Pigment Mixture)
The PSZ (Partially Stabilized Zirconia) balls were placed in a φ15 cm glass pot half-filled by volume, and ball milling was performed for 10 days. Trisazo pigment 20.0 g (Exemplified compound No. A-70) Disazo pigment 20.0 g (Exemplified compound No. B-17, 24) Cyclohexane 360 g

After that, the pigment dispersion liquid was discharged, and blade coating was attempted on the aluminum plate as a charge generation layer coating liquid, but it was impossible to coat because the dispersibility was poor and the particle size was too large. When the dispersion was dried and the particles were observed with an optical microscope, the particle diameter was 5 μm or more. The dispersion is subjected to suction filtration using a resin filter (Fluoropore: manufactured by Sumitomo Electric Industries, Ltd.) having a pore size of 0.1 μm, and the solid content remaining on the filter is vacuum dried at 120 ° C. for 1 day to obtain a pigment mixture. It was

(Preparation of Coating Solution for Charge Generation Layer) The obtained pigment mixture and solvent were placed in a φ15 cm glass pot half-filled with φ10 mm PSZ (partially stabilized zirconia) balls by volume, and ball-milled for 14 days (first order). Dispersion). Pigment mixture 36.7 g Methyl ethyl ketone 330 g Thereafter, cyclohexanone 625 g was added, and ball milling (secondary dispersion) was performed for 2 hours to obtain a mill base. The mill base obtained after that was diluted with cyclohexanone in which polyvinyl butyral resin (XYHL: UCC) and methyl ethyl ketone were dissolved to obtain a solid concentration of 1.
4%, pigment / butyral resin ratio = 3/1, cyclohexanone / methyl ethyl ketone ratio = 3/1, and a charge generation layer coating liquid was obtained.

The above charge generation layer liquid is applied onto an aluminum plate (JIS 1080) having a thickness of 0.2 mm by dipping and then dried at 120 ° C. for 10 minutes to form a charge generation layer having a thickness of about 0.2 μm. did.

Next, a charge transport layer solution prepared by stirring and dissolving the following compounds was applied onto the charge generating layer by dipping, and dried at 120 ° C. for 20 minutes to give a thickness of about 28 μm.
A charge transport layer of m was formed to prepare a photoreceptor.

[0128] (Composition of charge transport layer coating liquid)     9 parts by weight of the charge transport material represented by the structural formula 32     Bisphenol Z type polycarbonate resin 10 parts by weight       (TS2050: manufactured by Teijin Chemicals) viscosity average molecular weight 40,000     Silicone oil (KF50: manufactured by Shin-Etsu Silicone) 0.002 parts by weight     108 parts by weight of dichloromethane

Example 2-2 (Preparation of Pigment Mixture)
The PSZ (Partially Stabilized Zirconia) balls were placed in a φ15 cm glass pot half-filled by volume, and ball milling was performed for 10 days. Trisazo pigment 20.0 g (Exemplified compound No. A-70) Disazo pigment 20.0 g (Exemplified compound No. B-17, 24) Water 360 g

After that, the pigment dispersion was discharged, and blade coating was attempted on an aluminum plate as a charge generation layer coating liquid, but the coating was impossible because the dispersibility was poor and the particle size was too large. When the dispersion was dried and the particles were observed with an optical microscope, the particle size was 10 μm or more. The dispersion is subjected to suction filtration using a resin filter (Fluoropore: manufactured by Sumitomo Electric Industries, Ltd.) having a pore size of 0.1 μm, and the solid content remaining on the filter is vacuum dried at 120 ° C. for 1 day to obtain a pigment mixture. It was

Then, a photoconductor was prepared in the same manner as in Example 2-1.

Example 2-3 (Preparation of Pigment Mixture)
The PSZ (Partially Stabilized Zirconia) balls were placed in a φ15 cm glass pot half-filled by volume, and ball milling was performed for 10 days. Trisazo pigment 20.0 g (Exemplified compound No. A-70) Disazo pigment 20.0 g (Exemplified compound No. B-17, 24) Isopropyl ether 360 g

After that, the pigment dispersion liquid was discharged, and blade coating was attempted on the aluminum plate as a charge generation layer coating liquid, but the coating was impossible because the dispersibility was poor and the particle size was too large. When the dispersion was dried and the particles were observed with an optical microscope, the particle diameter was 2 μm or more. The dispersion is subjected to suction filtration using a resin filter (Fluoropore: manufactured by Sumitomo Electric Industries, Ltd.) having a pore size of 0.1 μm, and the solid content remaining on the filter is vacuum dried at 120 ° C. for 1 day to obtain a pigment mixture. It was

Then, a photoconductor was prepared in the same manner as in Example 1.

Comparative Example 2-1 (Preparation of coating liquid for charge generation layer)
mm PSZ (partially stabilized zirconia) balls were placed in a φ15 cm glass pot half-filled by volume, and ball milling (primary dispersion) was performed for 14 days. Trisazo pigment 20.0 g (Exemplified compound No. A-70) Disazo pigment 20.0 g (Exemplified compound No. B-17, 24) Methyl ethyl ketone 360 g

Thereafter, 625 g of cyclohexanone was added, and ball milling (secondary dispersion) was carried out for 2 hours to obtain a mill base. The resulting mill base was diluted with cyclohexanone in which polyvinyl butyral resin (XYHL: manufactured by UCC) and methyl ethyl ketone were diluted to obtain a solid content concentration of 1.4% and a pigment / butyral resin ratio = 3 /.
1, cyclohexanone / methyl ethyl ketone ratio = 3 /
The charge generation layer coating solution was prepared so as to be 1.

The above charge generation layer liquid was applied onto an aluminum plate (JIS 1080) having a thickness of 0.2 mm by dipping and then dried at 120 ° C. for 10 minutes to form a charge generation layer having a thickness of about 0.2 μm. did.

Next, a charge transport layer solution prepared by stirring and dissolving the following compounds was applied onto the charge generating layer by dipping, and then dried at 120 ° C. for 20 minutes to give a thickness of about 28 μm.
A charge transport layer of m was formed to prepare a photoreceptor.

[0139] (Composition of charge transport layer coating liquid)     9 parts by weight of the charge transport material represented by the structural formula 32     Bisphenol Z type polycarbonate resin 10 parts by weight       (TS2050: manufactured by Teijin Chemicals) viscosity average molecular weight 40,000     Silicone oil (KF50: manufactured by Shin-Etsu Silicone) 0.002 parts by weight     108 parts by weight of dichloromethane

Comparative Example 2-2 (Preparation of coating liquid for charge generation layer)
A 0 mm PSZ (partially stabilized zirconia) ball was placed in a φ15 cm glass pot half-filled by volume, and ball milling (primary dispersion) was performed for 14 days. Trisazo pigment 5.0 g (Exemplified compound No. A-70) Disazo pigment 5.0 g (Exemplified compound No. B-17, 24) Polyvinyl butyral resin (XYHL: UCC) 3.33 g Cyclohexanone 390 g

Then, 600 g of cyclohexanone was added, and ball milling (secondary dispersion) was performed for 2 hours to obtain a charge generation layer coating solution.

The above charge generation layer liquid was applied onto an aluminum plate (JIS 1080) having a thickness of 0.2 mm by a doctor blade having a gap of 50 μm, and then 120 ° C.
It was dried for 0 minutes to form a charge generation layer having a thickness of about 0.2 μm.

Next, a charge transport layer liquid prepared by stirring and dissolving the following compounds was applied onto the charge generating layer with a doctor blade and then dried at 120 ° C. for 20 minutes to give a thickness of about 28 μm. A charge transport layer was formed to prepare a photoreceptor.

[0144] (Composition of charge transport layer coating liquid)     9 parts by weight of the charge transport material represented by the structural formula 32     Bisphenol Z type polycarbonate resin 10 parts by weight       (TS2050: manufactured by Teijin Chemicals) viscosity average molecular weight 40,000     Silicone oil (KF50: manufactured by Shin-Etsu Silicone) 0.002 parts by weight     86 parts by weight of dichloromethane

The electrophotographic photosensitive member prepared as described above was charged in a dynamic mode with an electrophotographic characteristic measuring apparatus EPA8100 (manufactured by Kawaguchi Electric Co., Ltd.), and the photosensitive member was charged by −800 V.
780n light from a tungsten lamp with a color temperature of 2856K
The photosensitivity was measured by irradiating through a bandpass filter of m (half-width of 13 nm). Light sensitivity S _800-100 ( _Vc
m ² / μJ) has a surface potential of −800V to −100V.
The exposure amount required for attenuation to E (μJ / cm ² ) is determined by S _800-100 = 700 / E. Further, the viscosity of the charge generation layer coating liquid prepared as described above was measured using an E-type viscosity type (manufactured by Tokyo Keiki Co., Ltd .: type ELD). The characteristics of the charge generation layer coating liquid after 1 day and after storage with stirring for 1 month are shown below.

[0146]

[Table 20]

Prepared using a pigment mixture obtained by simultaneously pulverizing and mixing one or more trisazo pigments and one or more disazo pigments in the poorly dispersible solvents of Examples 2-1 to 2-3. It can be seen that the photoconductor and the coating liquid for the charge generation layer have high sensitivity and excellent storage stability.
In Comparative Example 2-1, which was dispersed with methyl ethyl ketone without pre-dispersion, the storage stability of the coating liquid was excellent, but the sensitivity was poor. Similarly, it can be seen that Comparative Example 2-2 dispersed with cyclohexanone has good sensitivity, but poor storage stability of the coating liquid.

Example 3-1 (Preparation of coating liquid for charge generation layer)
A 0 mm PSZ (partially stabilized zirconia) ball was placed in a φ15 cm glass pot half-filled by volume, and
Ball milling (primary dispersion) was performed for a day. Trisazo pigment 30.0 g (Exemplified compound No. A-70) Disazo pigment 10.0 g (Exemplified compound No. B-17, 24) Cyclohexanone 180 g Cyclohexane 180 g

Then, 300 g of cyclohexanone and 300 g of cyclohexane were added, and ball milling (secondary dispersion) was carried out for 2 hours to obtain a mill base. The mill base obtained after that was treated with a polyvinyl butyral resin (XYHL:
(Manufactured by UCC Co., Ltd.) was diluted with dissolved cyclohexanone and cycloxane to prepare a solid content concentration of 2.4%, a pigment / butyral resin ratio = 3/1, and a cyclohexanone / cycloxane ratio = 3/1. A coating solution for the generating layer was obtained. The above charge generation layer liquid was applied onto an aluminum plate (JIS 1080) having a thickness of 0.2 mm by dipping and then dried at 120 ° C. for 10 minutes to form a charge generation layer having a thickness of about 0.2 μm.

Next, the charge transport layer liquid prepared by stirring and dissolving the following compounds was applied onto the charge generating layer by dipping, and then dried at 120 ° C. for 20 minutes to give a thickness of about 28 μm.
A charge transporting layer was formed to prepare a photoreceptor.

[0151] (Composition of charge transport layer coating liquid)     9 parts by weight of the charge transport material represented by the structural formula 32     Bisphenol Z type polycarbonate resin 10 parts by weight       (TS2050: manufactured by Teijin Chemicals) viscosity average molecular weight 40,000     Silicone oil (KF50: manufactured by Shin-Etsu Silicone) 0.002 parts by weight     108 parts by weight of dichloromethane

Example 3-2 A photoconductor was prepared in the same manner as in Example 3-1, except that positive hexane was used instead of cyclohexane in the preparation of the charge generation layer coating solution of Example 3-1. did.

Example 3-3 A photoconductor was prepared in the same manner as in Example 3-1, except that ethyl acetate was used in place of cyclohexane in the preparation of the charge generation layer coating solution of Example 3-1. did.

Example 3-4 A photoconductor was prepared in the same manner as in Example 3-1, except that methyl acetate was used in place of cyclohexane in the preparation of the charge generation layer coating solution of Example 3-1. did.

Comparative Example 3-1 (Preparation of coating liquid for charge generating layer)
A 0 mm PSZ (partially stabilized zirconia) ball was placed in a φ15 cm glass pot half-filled by volume, and ball milling (primary dispersion) was performed for 14 days. Trisazo pigment 30.0 g (Exemplified compound No. A-70) Disazo pigment 10.0 g (Exemplified compound No. B-17, 24) Cyclohexane 360 g

Then, 480 g of cyclohexanone and 120 g of cyclohexane were added, and ball milling (secondary dispersion) was carried out for 2 hours to obtain a mill base. The mill base obtained after that was treated with a polyvinyl butyral resin (XYHL:
(Manufactured by UCC) was diluted with dissolved cyclohexanone and cyclohexane to prepare a solid content concentration of 2.4%, a pigment / butyral resin ratio = 3/1, and a cyclohexanone / cyclohexane ratio = 3/1. A coating solution for the generating layer was obtained. The above charge generation layer liquid was applied onto an aluminum plate (JIS 1080) having a thickness of 0.2 mm by dipping and then dried at 120 ° C. for 10 minutes to form a charge generation layer having a thickness of about 0.2 μm.

Thereafter, in the same manner as in Example 3-1, a charge transport layer coating liquid was prepared and coated to prepare a photoreceptor.

Comparative Example 3-2 A photoreceptor was prepared in the same manner as in Comparative Example 3-1 except that ethyl acetate was used instead of cyclohexane in the preparation of the charge generation layer coating solution of Comparative Example 3-1. did.

Comparative Example 3-3 (Preparation of coating liquid for charge generation layer)
A 0 mm PSZ (partially stabilized zirconia) ball was placed in a φ15 cm glass pot half-filled by volume, and
Ball milling (primary dispersion) was performed for a day. Trisazo pigment 7.5 g (Exemplified compound No. A-70) Disazo pigment 2.5 g (Exemplified compound No. B-17, 24) Polyvinyl butyral resin (XYHL: manufactured by UCC) 3.33 g Cyclohexanone 390 g

Thereafter, 600 g of cyclohexanone was added, and ball milling (secondary dispersion) was performed for 2 hours to obtain a charge generation layer coating solution.

The above charge generation layer liquid was applied onto an aluminum plate (JIS 1080) having a thickness of 0.2 mm by a doctor blade having a gap of 50 μm, and then 120 ° C., 1
It was dried for 0 minutes to form a charge generation layer having a thickness of about 0.2 μm.

Next, the charge transport layer liquid prepared by stirring and dissolving the following compounds was applied onto the charge generating layer with a doctor blade, and then dried at 120 ° C. for 20 minutes to give a thickness of about 28 μm. A charge transport layer was formed to prepare a photoreceptor.

[0163] (Composition of charge transport layer coating liquid)     9 parts by weight of the charge transport material represented by the structural formula 32     Bisphenol Z type polycarbonate resin 10 parts by weight       (TS2050: manufactured by Teijin Chemicals) viscosity average molecular weight 40,000     Silicone oil (KF50: manufactured by Shin-Etsu Silicone) 0.002 parts by weight     86 parts by weight of dichloromethane

The electrophotographic photosensitive member produced as described above was charged in a dynamic mode with an electrophotographic characteristic measuring apparatus EPA8100 (manufactured by Kawaguchi Denki Co., Ltd.) in a dynamic mode.
780n light from a tungsten lamp with a color temperature of 2856K
The photosensitivity was measured by irradiating through a bandpass filter of m (half-width of 13 nm). Light sensitivity S _800-100 ( _Vc
m ² / μJ) has a surface potential of −800V to −100V.
The exposure amount required for attenuation to E (μJ / cm ² ) is determined by S _800-100 = 700 / E. Further, the viscosity of the charge generation layer coating liquid prepared as described above was measured using an E-type viscosity type (manufactured by Tokyo Keiki Co., Ltd .: type ELD). The characteristics of the charge generation layer coating liquid after 1 day and after storage with stirring for 1 month are shown below.

[0165]

[Table 21]

One or more trisazo pigments and one kind in a mixed solvent of the cyclic ketone solvent and the saturated hydrocarbon solvent of Examples 3-1 to 3-4 or a mixed solvent of the cyclic ketone solvent and the ester solvent. It can be seen that the photoconductor and the charge generation layer coating liquid prepared by simultaneously pulverizing and mixing the above disazo pigments have high sensitivity and excellent storage stability. Comparative Example 3-
In the case where the cycloxane of 1 alone was used as the dispersion medium, the dispersibility was poor and coating was impossible. The dispersion of Comparative Example 3-2 dispersed with ethyl acetate has excellent storage stability of the coating solution but poor sensitivity. It can be seen that the dispersion of Comparative Example 3-3 with cyclohexanone has good sensitivity, but poor storage stability of the coating liquid.

Example 4-1 (Preparation of coating liquid for charge generation layer)
A 0 mm PSZ (partially stabilized zirconia) ball was placed in a φ15 cm glass pot half-filled by volume, and
Ball milling (primary dispersion) was performed for a day. Trisazo pigment 30.0 g (Exemplified compound No. A-70) Disazo pigment 10.0 g (Exemplified compound No. B-17) Cyclohexanone 180 g 2-Butanone 180 g

Then, cyclohexanone 300 g, 2-
Add 300 g of butanone and ball mill for 2 hours (2
Next dispersion) was performed to obtain a mill base. The mill base obtained after that was treated with polyvinyl butyral resin (XYHL: UC
(Manufactured by Company C) was diluted with dissolved cyclohexanone and 2-butanone to obtain a solid content concentration of 2.4%, a pigment / butyral resin ratio = 3/1, and a cyclohexanone / 2-butanone ratio = 3/1. A charge generation layer coating liquid was prepared. After the above charge generation layer liquid is dip-coated on an aluminum plate (JIS 1080) having a thickness of 0.2 mm, 12
It was dried at 0 ° C. for 10 minutes to form a charge generation layer having a thickness of about 0.2 μm.

Next, the charge transport layer liquid prepared by stirring and dissolving the following compounds was applied on the charge generating layer by dipping, and then dried at 120 ° C. for 20 minutes to give a thickness of about 28 μm.
A charge transporting layer was formed to prepare a photoreceptor.

[0170] (Composition of charge transport layer coating liquid)     9 parts by weight of the charge transport material represented by the structural formula 32     Bisphenol Z type polycarbonate resin 10 parts by weight       (TS2050: manufactured by Teijin Chemicals) viscosity average molecular weight 40,000     Silicone oil (KF50: manufactured by Shin-Etsu Silicone) 0.002 parts by weight     108 parts by weight of dichloromethane

Example 4-2 In the preparation of the charge generation layer coating liquid of Example 4-1,
A photoreceptor was prepared in the same manner as in Example 4-1, except that 4-methyl-2-pentanone was used instead of butanone.

Example 4-3 In the preparation of the charge generation layer coating solution of Example 4-1,
A photoconductor was prepared in the same manner as in Example 4-1, except that acetone was used instead of butanone.

Example 4-4 In the preparation of the charge generation layer coating solution of Example 4-1,
A photoconductor was prepared in the same manner as in Example 4-1, except that 3-pentanone was used instead of butanone.

Comparative Example 4-1 (Preparation of Charge Generation Layer Coating Liquid) The following pigments and solvents were mixed with φ1
A 0 mm PSZ (partially stabilized zirconia) ball was placed in a φ15 cm glass pot half-filled by volume, and ball milling (primary dispersion) was performed for 14 days. Trisazo pigment 30.0 g (Exemplified compound No. A-70) Disazo pigment 10.0 g (Exemplified compound No. B-17) 2-butanone 360 g

Thereafter, 480 g of cyclohexanone, 2-
Add butanone 120g and ball milling for 2 hours (2
Next dispersion) was performed to obtain a mill base. The mill base obtained after that was treated with polyvinyl butyral resin (XYHL: UC
(Manufactured by Company C) was diluted with dissolved cyclohexanone and 2-butanone to obtain a solid content concentration of 2.4%, a pigment / butyral resin ratio = 3/1, and a cyclohexanone / 2-butanone ratio = 3/1. A charge generation layer coating liquid was prepared. After the above charge generation layer liquid is dip-coated on an aluminum plate (JIS 1080) having a thickness of 0.2 mm, 12
It was dried at 0 ° C. for 10 minutes to form a charge generation layer having a thickness of about 0.2 μm.

Thereafter, in the same manner as in Example 4-1, a charge transport layer coating liquid was prepared and coated to prepare a photoreceptor.

Comparative Example 4-2 (Preparation of coating liquid for charge generation layer)
A 0 mm PSZ (partially stabilized zirconia) ball was placed in a φ15 cm glass pot half-filled by volume, and
Ball milling (primary dispersion) was performed for a day. Trisazo pigment 7.5 g (Exemplified compound No. A-70) Disazo pigment 2.5 g (Exemplified compound No. B-17) Polyvinyl butyral resin (XYHL: UCC) 3.33 g Cyclohexanone 390 g

Thereafter, 600 g of cyclohexanone was added, and ball milling (secondary dispersion) was carried out for 2 hours to obtain a charge generation layer coating solution.

The above charge generation layer liquid was applied onto an aluminum plate (JIS 1080) having a thickness of 0.2 mm with a doctor blade having a gap of 50 μm, and then 120 ° C.
It was dried for 0 minutes to form a charge generation layer having a thickness of about 0.2 μm.

Next, the charge transport layer liquid prepared by stirring and dissolving the following compounds was applied onto the charge generating layer with a doctor blade and dried at 120 ° C. for 20 minutes to give a thickness of about 28 μm. A charge transport layer was formed to prepare a photoreceptor.

[0181] (Composition of charge transport layer coating liquid)     9 parts by weight of the charge transport material represented by the structural formula 32     Bisphenol Z type polycarbonate resin 10 parts by weight       (TS2050: manufactured by Teijin Chemicals) viscosity average molecular weight 40,000     Silicone oil (KF50: manufactured by Shin-Etsu Silicone) 0.002 parts by weight     86 parts by weight of dichloromethane

The electrophotographic photosensitive member produced as described above was charged in a dynamic mode with an electrophotographic characteristic measuring apparatus EPA8100 (manufactured by Kawaguchi Electric Co., Ltd.), and the photosensitive member was charged at -800 V.
780n light from a tungsten lamp with a color temperature of 2856K
The photosensitivity was measured by irradiating through a bandpass filter of m (half-width of 13 nm). Light sensitivity S _800-100 ( _Vc
m ² / μJ) has a surface potential of −800V to −100V.
The exposure amount required for attenuation to E (μJ / cm ² ) is determined by S _800-100 = 700 / E. Further, the viscosity of the charge generation layer coating liquid prepared as described above was measured using an E-type viscosity type (manufactured by Tokyo Keiki Co., Ltd .: type ELD). The characteristics of the charge generation layer coating liquid after 1 day and after storage with stirring for 1 month are shown below.

[0183]

[Table 22]

It was prepared by simultaneously pulverizing and mixing at least one trisazo pigment and at least one disazo pigment in a mixed solvent of the cyclic ketone solvent and the chain ketone solvent of Examples 4-1 to 4-4. It can be seen that the photoconductor and the charge generation layer coating liquid have high sensitivity and excellent storage stability. Comparative Example 4-
The dispersion of 2-butanone of No. 1 has excellent storage stability of the coating solution but poor sensitivity. It can be seen that the cyclohexanone-dispersed product of Comparative Example 4-2 has good sensitivity but poor storage stability of the coating liquid.

[0185]

Pigment mixture according to claim 1 according to the present invention, the ring-like ketone solvents and a mixed solvent of saturated hydrocarbon solvents, cyclic ketone solvents and ester-based mixed solvent, or cyclic ketone solvent and a chain ketone solvent solvent It is obtained by simultaneously pulverizing and mixing one or more types of trisazo pigments and one or more types of disazo pigments in the mixed solvent of (1) above, and thus all have high sensitivity.

The pigment mixture of claims 2 to 4 comprises the trisazo pigment represented by the general formula 1 and the disazo pigment represented by the general formula 2 (they are represented by the general formula 3 or 4). (Including a tris- and / or disazo pigment having a coupler residue), which is obtained by simultaneously pulverizing and mixing in a solvent, Since the disazo pigment (Chemical Formula 2) has a high charge generation ability by irradiation with light in the infrared light region and the charge generation ability by irradiation with light in the visible light region is high, the obtained pigment mixture is It has a high charge generation capability in a wide range of wavelengths.

Since the method for producing a pigment mixture according to claim 5 comprises simultaneously pulverizing and mixing one or more trisazo pigments and one or more disazo pigments in the solvent, a highly sensitive pigment mixture can be easily prepared. Obtainable.

[0188] photosensitive layer coating solution of claim 6, containing said at mixed-solvent, pigment mixture obtained by simultaneously pulverized and mixed one more trisazo pigment and one or more disazo pigment Because of the above composition, the storage stability of the coating liquid is excellent.

The electrophotographic photosensitive member according to claim 7 is configured to contain a pigment mixture obtained by simultaneously pulverizing and mixing one or more trisazo pigments and one or more disazo pigments in the solvent. Therefore, it has sensitivity over a wider wavelength range than when a photoreceptor is designed by using each individual pigment alone, and has higher sensitivity than when a photoreceptor is designed by using each individual pigment alone.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ identification code FI G03G 5/06 348 G03G 5/06 348 360 360C 367 367 (56) Reference JP-A-6-49433 (JP, A) JP-A-3-230168 (JP, A) JP-A-2-226257 (JP, A) JP-A-4-24970 (JP, A) JP-A-7-114195 (JP, A) JP-A-7-219256 (JP , A) JP-A-3-196049 (JP, A) JP-A-7-199490 (JP, A) JP-A-62-44746 (JP, A) JP-A-63-56658 (JP, A) (58) Fields surveyed (Int.Cl. ⁷ , DB name) C09B 67/10 C09B 67/04 C09B 67/20 C09B 67/22 G03G 5/06

Claims (7)

(57) [Claims] 1. One or more kinds in a mixed solvent of a cyclic ketone solvent and a saturated hydrocarbon solvent, a mixed solvent of a cyclic ketone solvent and an ester solvent, or a mixed solvent of a cyclic ketone solvent and a chain ketone solvent. also it is obtained by grinding and mixing process trisazo pigments and one or more disazo pigment simultaneously
Therefore, the crushing and mixing treatment is performed from the primary dispersion and the secondary dispersion.
And both primary dispersion and secondary dispersion are performed in a mixed solvent.
A pigment mixture which is characterized by being brown. 2. The pigment mixture according to claim 1, wherein the trisazo pigment is represented by the following general formula 1, and the disazo pigment is represented by the following general formula 2. [Chemical 1] [Chemical 2] [However, in the general formulas 1 and 2 above, Ar ¹ , Ar ² , Ar
³ , Ar ⁴ and Ar ⁵ represent a coupler residue and may be the same or different. ] 3. Coupler residues Ar ¹ , Ar ² , Ar ³ , Ar ⁴ and Ar represented by the general formula 1 and / or formula ² .
⁵ trisazo pigments and / or disazo pigment represented by the following general formalized 3 ^{(wherein, Ar 1, Ar 2, Ar} 3, Ar 4 and Ar ⁵ may be the same or different) a is claim 2 The pigment mixture according to 1. [Chemical 3] [However, in the above formula, X ¹ , Y ¹ and Z respectively represent the following. ^{X 1: -OH, -N (R} 1) (R 2) or -NHSO ₂ -R
³ . (R ¹ and R ² represent a hydrogen atom, an acyl group 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 atom A halogen atom, a substituted or unsubstituted alkyl group, an alkoxy group, a carboxy group, a sulfone group, a benzimidazolyl group, a substituted or unsubstituted sulfamoyl group, a substituted or unsubstituted allofanoyl group or -CON (R ⁴ ) (Y ² ) Represents. {R ⁴ represents a hydrogen atom, an alkyl group or a substituted product thereof, a phenyl group or a substituted product thereof, and Y ² represents a hydrocarbon ring group or a substituted product thereof, a heterocyclic group or a substituted product thereof, or -N =
C (R ⁵ ) (R ⁶ ) (wherein R ⁵ is 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, and R ⁶ is a hydrogen atom, an alkyl group or a substituted product thereof. Or a phenyl group or a substituted form thereof, or R ⁵ and R ⁶ may form a ring together with the carbon atom bonded to them. } Z: Hydrocarbon ring group or a substituted body thereof, or heterocyclic group or a substituted body thereof. ] 4. The coupler residues Ar ¹ , Ar ² , Ar ³ , Ar ⁴ and Ar represented by the general formula 1 and / or formula ² .
⁵ trisazo pigments and / or disazo pigment represented by the following general formalized 4 ^{(wherein, Ar 1, Ar 2, Ar} 3, Ar 4 and Ar ⁵ may be the same or different) a is claim 2 The pigment mixture according to 1. [Chemical 4] [However, in the above formula, R ⁷ , R ⁸ , Y ¹ and n respectively represent the following. n: An integer of 1 to 4. R ⁷ : hydrogen atom, substituted or unsubstituted alkyl group or substituted or unsubstituted aryl group. R ⁸ : hydrogen atom, substituted or unsubstituted alkyl group, substituted or unsubstituted alkoxy group, substituted or unsubstituted alkylsulfonyl group, substituted or unsubstituted alkylmercapto group, halogen atom, substituted or unsubstituted aryl group Represents a substituted or unsubstituted acyl group, cyano group, nitro group or substituted or unsubstituted amino group, and when n is an integer of 2 to 4, R ⁸ may be the same or different. Y ¹ : Same as in General Formula 3. ] 5. A cyclic ketone-based solvent and a saturated hydrocarbon-based solvent containing at least one trisazo pigment and at least one disazo pigment.
Mixed solvent, mixed cyclic ketone solvent and ester solvent
Method for producing a pigment mixture which pulverized and mixed simultaneously mixed solvent or cyclic ketone solvent and a chain ketone mixed <br/> solvent solvent
And the pulverizing and mixing treatment consists of primary dispersion and secondary dispersion.
And both primary dispersion and secondary dispersion in a mixed solvent.
Producing how the pigment mixture, characterized in that the Hare. 6. A photosensitive layer coating liquid containing the pigment mixture according to claim 1 as an active ingredient. 7. A by forming a photoconductive layer on a conductive support an electrophotographic photosensitive member, pigments according to any one of claims 1-4 in at least one layer which forms a photoconductive layer An electrophotographic photoreceptor containing a mixture.