JPH10232500A - Electrophotographic photoreceptor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the electrophotographic photoreceptor optimum for a copying machine and a printer and the like using semiconductor laser beams and small in fluctuation potential acceptance and rise of residual potential. SOLUTION: A photosensitive layer formed on a conductive substrate contains an oxytitanylphthalocyanine pigment as a charge generating material and at least a polycrown-ether compound represented by the formula in which each of ring A and ring B is, independently, is a benzene or cyclohexyl ring, and each of (l) and (m) is, independently, an integer of 0-3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic photosensitive member used for a copying machine, a printer, etc. using an electrophotographic process. The present invention relates to an electrophotographic photoreceptor having a low density.

[0002]

2. Description of the Related Art Conventionally, selenium,
Electrophotographic photoreceptors composed of inorganic compounds such as selenium-tellurium alloy and arsenic-selenium have been used in many copying machines. However, electrophotographic photoreceptors using these inorganic materials have environmental problems such as toxicity, and because they are used in an amorphous state, for example, they are easily crystallized by heat, dirt, and the like, and the characteristics are easily deteriorated. Handling is cumbersome. In addition, there is a disadvantage that the cost is increased because it is necessary to perform vacuum deposition to a film thickness of several tens of μm.

On the other hand, an electrophotographic photoreceptor using an organic material has advantages such as low cost, low toxicity and suitability for mass production. became. Most of the electrophotographic photoreceptors that have been put into practical use are function-separated electrophotographic photoreceptors in which a charge generation layer having a charge generation function and a charge transport layer having a charge transport function are laminated on a conductive substrate. This improved the sensitivity and life of the photoconductor, which were inferior to those of electrophotographic photoconductors using inorganic materials, and made it possible to use low-cost, electronic devices that take advantage of organic photoconductive materials such as safety and versatility. The design of photoreceptors has been actively pursued.

In this type of laminated electrophotographic photoreceptor, generally, a charge generation layer composed of a charge generation substance such as a pigment and a dye, and a charge transport layer composed of a charge transport substance are sequentially laminated on a conductive support. It has a configuration as described below. Such a function-separated type electrophotographic photoreceptor has an advantage that a wide selection range of each material of a charge generating substance and a charge transporting substance and an electrophotographic photoreceptor having arbitrary characteristics can be relatively easily produced. doing.

On the other hand, in the copying industry, in recent years, an editing function and a complex processing function with high image quality have been demanded. Along with this, non-impact printing techniques have been developed, and digital recording apparatuses such as those used in laser printers, laser facsimile machines, digital copiers and the like have been widely used.

As a light source used in the above-mentioned digital recording apparatus, a semiconductor laser is used in many cases because of its small size, low cost, and simplicity. However, the oscillation wavelength of the semiconductor currently used is 750 nm. It is limited to the near infrared region described above. Therefore, the electrophotographic photosensitive member used in these devices is required to have photosensitivity in a wavelength region of at least 750 to 850 nm.

As organic photoconductive materials satisfying this requirement, phthalocyanine pigments, azo pigments, cyanine pigments, azulene pigments, squarium pigments and the like are known.
In particular, phthalocyanine pigments have spectral absorption up to a relatively long wavelength region, have photosensitivity, and have various variations depending on the type of central metal and crystal form. Research is being conducted.

The phthalocyanine pigments known so far include ε-type copper phthalocyanine, X-type metal-free phthalocyanine, τ-type metal-free phthalocyanine, vanadyl phthalocyanine, titanyloxy phthalocyanine, and the like. However, the repetition durability is still insufficient, and further improvement has been desired.

On the other hand, in recent years, for higher sensitivity, for example, Japanese Patent Application Laid-Open No. 59-49544 (US Pat. No. 4,444,8)
61), JP-A-59-166959, JP-A-61-23
9248 (US Pat. No. 4,728,592);
67,094 (US Pat. No. 4,664,997);
-275272, JP-A-63-366, JP-A-63-1
16158, JP-A-63-198067, JP-A-64-
17066, JP-A-2-28265, JP-A-3-350
64, JP-A-3-200790 and the like have proposed a high-sensitivity oxytitanyl phthalocyanine pigment.

On the other hand, in an electrophotographic photoreceptor, not all charge transporting layers exhibit good characteristics with respect to a specific charge generating substance. On the other hand, charge transport materials exhibiting good properties,
There are combinations of additives such as antioxidants. In the case of an inappropriate combination, many problems such as a decrease in sensitivity, an increase in residual potential, and a decrease in charging stability occur.

The above oxytitanyl phthalocyanine pigments are disclosed in JP-A-1-82043 and JP-A-2-1368.
62, Japanese Patent Application Laid-Open No. 2-189555 and the like have proposed a combination with a specific charge transport material.
No satisfactory results have been obtained in terms of sensitivity, residual potential, potential stability upon repeated use, and the like.

It is also known to add an additive to a photoconductor in order to prevent deterioration due to light irradiation and to prevent deterioration of the photoconductor material due to ozone or nitrogen oxide (NOx) generated by corona discharge. For example, see Japanese Patent Application Laid-Open No.
5, JP-A-6-175381, JP-A-3-188456
However, no photoconductor satisfying the required performance has been obtained.

[0013]

SUMMARY OF THE INVENTION An object of the present invention is to provide an electrophotographic photosensitive member having a good sensitivity to long-wavelength light and particularly suitable for a recording apparatus such as a copying machine or a printer using a semiconductor laser beam as a light source. Is to provide the body. Another object of the present invention is to provide an electrophotographic photoreceptor which particularly contains an oxytitanyl phthalocyanine pigment as a charge generating substance, has no change in chargeability even when used repeatedly, and has extremely high durability with little increase in residual potential. It is to provide.

[0014]

According to the present invention, first, an oxytitanyl phthalocyanine pigment is used as a charge generating material on a conductive support, and at least the pigment is represented by the following general formula (1). An electrophotographic photoreceptor characterized by providing a photosensitive layer containing a polycrown ether compound is provided.

Embedded image In the formula, A ring and B ring each independently represent a benzene ring or a cyclohexyl ring, and l and m each independently represent an integer of 0 to 3. Second, an oxytitanyl phthalocyanine pigment is used as a charge generating substance on a conductive support, and the charge generating layer and the hole transporting substance containing the pigment and the polycrown ether compound represented by the above general formula (1) are used. The present invention provides a negatively charged electrophotographic photoreceptor, characterized in that the charge transport layers contained therein are laminated and provided in this order.
Thirdly, in the negatively charged electrophotographic photoreceptor described in the second aspect, the hole transporting material is a stilbene compound represented by the following general formula (2). Is provided.

Embedded image In the formula, r ₁ and r ₂ are a substituted or unsubstituted alkyl group,
Represents a substituted or unsubstituted aryl group, and r ₃ and r ₄ are
Represents a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group or a heterocyclic group. Also,
r ₁ and r ₂ may form a ring. Fourthly, an oxytitanyl phthalocyanine pigment is used as a charge generating material on a conductive support, and a charge generation containing the pigment and the polycrown ether compound represented by the general formula (1) is used. A positively chargeable electrophotographic photoreceptor is provided, in which a layer and a charge transport layer containing an electron transport substance are laminated and provided in this order. Fifth, in the positively chargeable electrophotographic photoreceptor described in the fourth aspect, the electron transporting substance is (2,3-diphenyl-1-indenylidene) malononitrile represented by the following formula (3). To provide a positively charged electrophotographic photosensitive member.

Embedded image Sixth, an oxytitanyl phthalocyanine pigment is used as a charge generating substance on a conductive support, and the pigment, an electron transporting substance or a hole transporting substance, and a polycrown ether compound represented by the above general formula (1) are contained. An electrophotographic photoreceptor characterized by providing a single photosensitive layer is provided.

Hereinafter, the present invention will be described in detail. As described above, the electrophotographic photoreceptor of the present invention uses an oxytitanyl phthalocyanine pigment as a charge generating material on a conductive support, and contains at least the pigment and a polycrown ether compound represented by the general formula (1). A light-sensitive layer is provided. That is, according to such a configuration, it has good sensitivity to the semiconductor laser light, and
An electrophotographic photosensitive member having excellent potential stability upon repeated use can be obtained.

The photosensitive layer comprises a function-separated type photoconductor in which a charge generation layer made of a charge generation material and a charge transport layer made of a charge transport material are laminated, and the charge generation material and the charge transport material are combined into a single photosensitive layer. It is applied to the contained single-layer type photoreceptor. That is, in the case of a function-separated type photoreceptor, the oxytitanyl phthalocyanine pigment is used as a charge generating substance, and the pigment and the charge generating layer containing a polycrown ether compound and the charge transporting layer containing a charge transporting substance are used. Be composed. When a hole transport material is used as the charge transport material, a negatively charged electrophotographic photoreceptor is obtained, and when an electron transport material is used as the charge transport material, a positively charged electrophotographic photoreceptor is obtained.

In both the negative charge type and the positive charge type, an electrophotographic photoreceptor having high sensitivity to semiconductor laser light can be obtained by including an oxytitanyl phthalocyanine pigment as a charge generating substance in the charge generating layer. Also,
Further, by including a polycrown ether compound represented by the above general formula (1) in the charge generation layer, it is possible to prevent a decrease in chargeability, a decrease in sensitivity, and a rise in residual potential during repeated use, thereby providing an electron with excellent potential stability. A photographic photoreceptor is obtained.

Also in the single-layer type photoreceptor, the photosensitive layer contains the above oxytitanyl phthalocyanine pigment as a charge generating substance, and further contains an electron transporting substance or a hole transporting substance and a polycrown represented by the above general formula (1). By containing an ether compound, it is possible to obtain an electrophotographic photoreceptor that has high sensitivity to semiconductor laser light, prevents chargeability reduction, sensitivity reduction and increase in residual potential during repeated use, and has excellent potential stability. Can be

[0019]

Embodiments of the present invention will be described below. The basic structure of the oxytitanyl phthalocyanine pigment used as the charge generating substance in the present invention is represented by the following general formula (4).

Embedded image In the formula, X ₁ , X ₂ , X ₃ and X ₄ each independently represent a halogen atom, and n, m, l and k each independently represent an integer of 0 to 4.

The oxytitanyl phthalocyanine pigment according to the present invention is obtained by aggregating oxytitanyl phthalocyanine having the above-mentioned basic structure. Examples of the synthesis are described in JP-A-62-275272 and JP-A-64-1766.
As described in JP-A-2-28265, JP-A-3-35064, JP-A-3-200790, JP-A-3-269064, etc., there are many crystal forms, and any crystal form can be used.

The photosensitive layer of the electrophotographic photosensitive member of the present invention contains a polycrown ether compound represented by the following general formula (1).

Embedded image In the formula, A ring and B ring each independently represent a benzene ring or a cyclohexyl ring, and l and m each independently represent an integer of 0 to 3.

When the photosensitive layer contains the polycrown ether compound represented by the general formula (1), the electrophotographic photosensitive member achieves an improvement in charging stability when repeatedly used.

The content of the polycrown ether compound in the light-sensitive layer is set to 0.1 to the charge generating substance.
1% to 50% by weight, preferably 0.1% to 30% by weight
% By weight. If the content is less than 0.1% by weight, the effect of reducing the residual potential and improving the repetition characteristics is not sufficient.
On the other hand, if the content is more than 50% by weight, the film quality and mechanical durability of the charge transport layer are poor, and the sensitivity is lowered.

For the synthesis of the polycrown ether compound, for example, the following literature can be used. E. FIG. Blasius et al. , Makromol.
Chem. 183, 1401 (1982) H. Pannel et al. , J. et al. Chem. S
oc. , Perkin I, 2153 (1982).

Hereinafter, a laminated type will be described as an embodiment of the photosensitive layer. First, as the conductive support, a metal plate of aluminum, nickel, copper, titanium, gold, or the like, a metal drum or metal foil, a plastic film on which aluminum, nickel, copper, titanium, tin oxide, indium oxide, or the like is deposited, or a conductive film A film or a drum made of paper, plastic, or the like coated with a conductive material can be used.

An undercoat layer having a barrier function and an adhesive function can be provided on the conductive support. Polyamide resin, polyvinyl alcohol, ethyl cellulose, carboxymethyl cellulose, vinyl chloride-vinyl acetate copolymer, vinyl chloride-vinyl acetate-
Resins such as maleic anhydride copolymer, casein, N-alkoxymethyl nylon, etc. are used as such, or tin oxide, aluminum oxide, titanium oxide, silicon oxide, or indium oxide is dispersed in these resins to form a coating layer. Alternatively, a deposited film of aluminum oxide, zinc oxide, titanium oxide, silicon oxide, or the like is provided. The thickness is in the range of 0.1 to 2 μm.

Next, the charge generation layer provided directly on the support or via the undercoat layer may be formed of only the above-mentioned oxytitanyl phthalocyanine pigment which is a charge generation substance and a polycrown ether compound, or The oxytitanyl phthalocyanine pigment and the polycrown ether compound may be formed by being dispersed in a binder resin.

When the charge generation layer is formed by dispersing the charge generation substance and the polycrown ether compound, the charge generation substance is preferably in the form of powder having an average particle diameter of 2 μm or less, preferably 1 μm or less. . That is, if the particle size is too large, the dispersion in the layer becomes worse, and the particles partially protrude from the surface to deteriorate the smoothness of the surface. In some cases, discharge occurs at the protruding portion of the particles, or toner particles are generated there. Adhere to the toner filming phenomenon. However, if the above particle size is too small, it is rather easy to aggregate, the resistance of the layer increases, the crystal defects increase, the sensitivity and the repetition characteristics decrease, or there is a limit in miniaturization. Is preferably 0.01 μm.

The charge generation layer can be provided by the following method. That is, the charge generation material and the polycrown ether compound are formed into fine particles in a dispersion medium by a ball mill, a homomixer, or the like, and a binder resin is added, if necessary, mixed and dispersed, and the resulting dispersion is applied. In this method, when the particles are dispersed under the action of ultrasonic waves, uniform dispersion is possible. In the charge generation layer, the ratio of the charge generation material contained in the binder resin is:
It is 20 to 200 parts by weight based on 100 parts by weight of the binder resin.

The thickness of the charge generation layer formed as described above is preferably from 0.1 to 10 μm, particularly preferably from 0.2 to 2 μm. In addition, a known charge generating substance, a dispersion stabilizer such as a surfactant, and an antioxidant can be added to the charge generation layer for the purpose of improving dispersion stability or characteristics.

Next, the charge transport layer provided on the charge generation layer is formed mainly of a charge transport material (a hole transport material or an electron transport material).

As the hole transporting substance, conventionally known hole transporting substances can be used, for example, a compound having a triphenylamine site in the molecule, a compound having a carbazole site, a hydrazone compound, a triphenylmethane compound,
Examples thereof include oxazole compounds, styryl compounds, butadiene compounds, polysilane compounds, polyvinyl carbazole, and donor compounds of pyrene-formalin condensed substances. Among them, a stilbene compound represented by the following general formula (2) is preferably used.

Embedded image In the formula, r ₁ and r ₂ are a substituted or unsubstituted alkyl group,
Represents a substituted or unsubstituted aryl group, and r ₃ and r ₄ are
Represents a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group or a heterocyclic group. Also,
r ₁ and r ₂ may form a ring with each other.

Specific examples of this stilbene compound are shown in Table 1-1.
However, the present invention is not limited to these.

[0034]

[Table 1-1]

[0035]

[Table 1-2]

[0036]

[Table 1-3]

As the electron transporting substance, conventionally known electron transporting substances can be used, for example, trinitrofluorenone,
Alternatively, a fluorene compound such as a fluorenylidenemethane derivative, a quinone compound such as a diphenoquinone, or an anthraquinone derivative may be used. Among them, (2,3-diphenyl-1-indenylidene) malononitrile of the following formula (3) is preferably used.

Embedded image

The charge transporting layer can be provided by dissolving or dispersing the charge transporting substance in an appropriate solvent together with a binder resin, if necessary, coating and drying. The ratio of the charge transport material to the binder resin in the charge transport layer is preferably 0 to 400 parts by weight, particularly 50 to 200 parts by weight, based on 100 parts by weight of the charge transport material. The thickness of the charge transport layer is preferably 5 to 50 μm, particularly preferably 10 to 30 μm.

Examples of the solvent used for preparing the dispersion or solution of the charge generation layer or the charge transport layer include N, N-dimethylformamide, toluene, xylene, monochlorobenzene, 1,2-dichloroethane, and the like.
1,1,1-trichloroethane, dichloromethane, 1,
Examples thereof include 1,2-trichloroethane, trichloroethylene, tetrahydrofuran, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, ethyl acetate, and butyl acetate.

Examples of the binder resin used for the charge generation layer or the charge transport layer include polyethylene, polyvinyl butyral, polyvinyl formal, polystyrene resin, polypropylene, acrylic resin, methacrylic resin, vinyl chloride resin, vinyl acetate resin, and epoxy resin. Resin, polyurethane resin, phenol resin, polyester resin, alkyd resin, polycarbonate resin, polyamide resin, silicone resin, addition polymerization type resin such as melamine resin, polyaddition type resin, polycondensation type resin, and repeating units of these resins Copolymer resins containing two or more of them, for example, vinyl chloride-vinyl acetate copolymer, styrene-acrylic copolymer, vinyl chloride-vinyl acetate-maleic anhydride copolymer resin, and other insulating resins, −
A high-molecular organic semiconductor such as N-vinylcarbazole may be used.

[0041]

EXAMPLES The present invention will be described below with reference to examples, but the embodiments of the present invention are not limited thereto.
First, a specific synthesis example of the oxytitanyl phthalocyanine pigment used in the examples will be described.

(Synthesis Example 1) 52.5 g of phthalodinitrile
(0.41 mol) and 300 ml of 1-chloronaphthalene
Are stirred and mixed, and 19.0 g of titanium tetrachloride is added under a nitrogen stream.
(0.1 mol) is added dropwise. After dropping, gradually add 20
The temperature was raised to 0 ° C, and the mixture was stirred and reacted for 5 hours while maintaining the reaction temperature at 190 to 210 ° C. After the completion of the reaction, the mixture was allowed to cool to 130 ° C., filtered while hot, washed with 1-chloronaphthalene until the powder turned blue, further washed with hot water at 80 ° C. several times, and dried and dried. As a result, 0.2 g (yield: 73.3%) of a crude oxytitanyl phthalocyanine pigment was obtained. 4 g of the obtained crude oxytitanyl phthalocyanine pigment was gradually dissolved in 80 g of 98% sulfuric acid at 5 ° C.
The mixture is stirred for about 1 hour while maintaining the temperature below 5 ° C. Subsequently, the sulfuric acid solution is slowly poured into 800 ml of ice water with high-speed stirring, and the precipitated crystals are filtered. The crystals were washed with distilled water until no acid remained, purified with acetone, and dried to obtain 3.6 g of an amorphous oxytitanyl phthalocyanine pigment.

(Synthesis Example 2) 6 g of the crude oxytitanyl phthalocyanine pigment obtained in the same manner as in Synthesis Example 1 was added at 5 ° C.
The mixture is gradually dissolved in 120 g of 98% sulfuric acid, and the mixture is stirred for about 1 hour while maintaining the temperature at 5 ° C. or less.
Subsequently, the sulfuric acid solution is slowly poured into 1200 ml of ice water with high-speed stirring, and the precipitated crystals are filtered. Crystal
The residue was washed with distilled water until no acid remained, to obtain a wet cake of an oxytitanyl phthalocyanine pigment. After 100 ml of 1,2-dichloroethane was added to the wet cake and stirred at room temperature for 2 hours, 300 ml of methanol was further added, stirred and filtered. This was washed with methanol and dried to obtain 4.9 g of a crystalline oxytitanyl phthalocyanine pigment. The X-ray diffraction spectrum of the obtained oxytitanyl phthalocyanine pigment was measured under the following conditions. X-ray tube Cu voltage 40 kV Current 20 mA Scanning speed 1 deg / min Scanning range 3-40 deg Time constant 2 sec

FIG. 1 shows an X-ray diffraction spectrum of the amorphous oxytitanyl phthalocyanine pigment obtained in Synthesis Example 1. There is no strong diffraction peak as shown in the X-ray diffraction diagram of FIG. FIG. 2 shows an X-ray diffraction spectrum of the crystalline oxytitanyl phthalocyanine pigment obtained in Synthesis Example 2. As shown in the X-ray diffraction diagram of FIG. 2, the Bragg angle 2θ 9.5 de
g and a major peak at 27.2 deg.

Example 1 3 parts of an alcohol-soluble polyamide (CM-8000, manufactured by Toray Industries, Inc.) was dissolved by heating in 100 parts of a mixed solvent of methanol / n-butanol = 8/2 (vol ratio), and coated for undercoat layer. A working solution was prepared. This is 75μ
m at 100 ° C.
After drying for 0 minutes, an undercoat layer having a thickness of 0.1 μm was prepared. Next, 2 parts of the crystalline oxytitanyl phthalocyanine pigment obtained in Synthesis Example 2 and a polycrown ether compound [poly (dibenzo-18-crown-6) formaldehyde:
Aldrich] 0.1 part, polyvinyl butyral resin (BM-S manufactured by Sekisui Chemical Co., Ltd.) 2 parts n-butyl acetate 4
The mixture was added to 6 parts and dispersed in a sand mill using 1 mmφ glass beads for 12 hours. After the dispersion is completed, acetic acid n-
150 parts of butyl was added and diluted to prepare a coating solution for a charge generation layer. This was applied on the undercoat layer and dried at 80 ° C. for 5 minutes to form a 0.2 μm-thick charge generation layer. Next, 8 parts of a hole transport material (the following formula (D-1)) and 1 part of a polycarbonate resin (Iupilon Z200 manufactured by Mitsubishi Gas Chemical Company)
0 parts, silicone oil (KF-50 manufactured by Shin-Etsu Chemical Co., Ltd.)
002 parts were dissolved in 100 parts of tetrahydrofuran to prepare a coating solution for a charge transport layer. This was applied on the charge generation layer and dried at 110 ° C. for 10 minutes to form a charge transport layer having a thickness of 20 μm. Thus, an electrophotographic photosensitive member of Example 1 was obtained.

Embedded image

Example 2 The polycrown ether compound [poly (dibenzo-18-crown-6) formaldehyde: Aldrich Co., Ltd.] used in Example 1 was changed to 0.4 part instead of 0.1 part. An electrophotographic photosensitive member was produced in the same manner as in Example 1.

Comparative Example 1 A polycrown ether compound [poly (dibenzo-18-crown-6) formaldehyde: manufactured by Aldrich] used in Example 1 was used in the same manner as in Example 1 except that it was not added. An electrophotographic photosensitive member was manufactured.

Example 3 As a hole transport material, the compound represented by the formula (D-
An electrophotographic photosensitive member was prepared in the same manner as in Example 1, except that the following formula (D-2) was used instead of using the compound of 1).

Embedded image

Comparative Example 2 A polycrown ether compound [poly (dibenzo-18-crown-6) formaldehyde: manufactured by Aldrich] used in Example 3 was used in the same manner as in Example 3 except that it was not added. An electrophotographic photosensitive member was manufactured.

Example 4 Synthesis Example 2 Used in Example 1
In the same manner as in Example 1 except that 2 parts of the amorphous oxytitanyl phthalocyanine pigment obtained in Synthesis Example 1 was used instead of 2 parts of the crystalline oxytitanyl phthalocyanine pigment obtained in A photoreceptor was obtained.

Comparative Example 3 A method similar to that of Example 4 was used except that the polycrown ether compound [poly (dibenzo-18-crown-6) formaldehyde: manufactured by Aldrich] used in Example 4 was not added. An electrophotographic photosensitive member was manufactured.

The electrophotographic photosensitive member obtained as described above was evaluated for electrostatic characteristics in a dynamic mode using EPA 8200 (manufactured by Kawaguchi Electric Works). First, the photosensitive member is negatively charged by performing a −6 KV corona discharge for 5 seconds, and the surface potential V ₂ (−V) after 2 seconds is measured.
When the voltage reaches 800 V, light (5.0 μW / cm ² ), which has been spectrally dispersed at 780 nm, is exposed using a band-pass filter, and an exposure amount E _1/2 (μJ) required for attenuating the surface potential to −400 V is obtained. / Cm ² ) and surface potential Vr after 30 seconds of exposure
(−V) was measured. In addition, -6 KV corona discharge and exposure to a tungsten lamp 45lux having a color temperature of 2856 K were repeated 10,000 times, and then the same measurement was performed to evaluate the electrostatic characteristics after fatigue. Table 2 shows the evaluation results.

[0053]

[Table 2]

Example 5 An intermediate layer and a charge generation layer were formed on a 75 μm aluminum-deposited PET base in the same manner as in Example 1. Next, 8 parts of an electron transport material represented by the following formula (A-1), 10 parts of a polycarbonate resin (Iupilon Z200 manufactured by Mitsubishi Gas Chemical Co., Ltd.), and 0.02 parts of silicon oil (KF50 manufactured by Shin-Etsu Chemical Co., Ltd.) were added to tetrahydrofuran 1
Of the charge generating layer, and
After drying at 10 ° C. for 10 minutes, a charge transport layer having a thickness of 20 μm was provided to produce an electrophotographic photosensitive member.

Embedded image

Example 6 The polycrown ether compound [poly (dibenzo-18-crown-6) formaldehyde: Aldrich Co.] used in Example 5 was changed from 0.1 part to 0.4 part. An electrophotographic photosensitive member was produced in the same manner as in Example 5.

Comparative Example 4 Example 5 was repeated except that the polycrown ether compound used in Example 5 was not added.
An electrophotographic photoreceptor was produced in the same manner as described above.

Example 7 Synthesis Example 2 Used in Example 5
An electrophotographic photoreceptor was prepared in the same manner as in Example 5, except that 2 parts of the amorphous oxytitanyl phthalocyanine pigment obtained in Synthesis Example 1 was used instead of 2 parts of the crystalline oxytitanyl phthalocyanine pigment obtained in Obtained.

Comparative Example 5 A method similar to that of Example 7 was used except that the polycrown ether compound [poly (dibenzo-18-crown-6) formaldehyde: manufactured by Aldrich] used in Example 7 was not added. An electrophotographic photosensitive member was manufactured.

Example 8 1 part of the crystalline oxytitanyl phthalocyanine pigment obtained in Synthesis Example 2, 4 parts of a polycarbonate resin (Iupilon Z200 manufactured by Mitsubishi Gas Chemical Company), a polycrown ether compound [poly (dibenzo-18-crown- 6) Formaldehyde: manufactured by Aldrich]
Add 0.1 part of tetrahydrofuran 45 parts and add 1 mm
Dispersion was performed for 12 hours with a sand mill using φ glass beads. After the dispersion is completed, the hole transport material (D-1) 7
Part, silicone oil (KF-50 manufactured by Shin-Etsu Chemical Co., Ltd.) 0.0
Two parts and 55 parts of tetrahydrofuran were added and redispersed to prepare a coating solution for a photoreceptor. This was applied on a 75 μm aluminum-deposited PET base and dried at 110 ° C. for 10 minutes to provide a photosensitive layer having a thickness of 20 μm, thereby obtaining a single-layer type electrophotographic photosensitive member.

Comparative Example 6 The same procedure as in Example 8 was carried out except that the polycrown ether compound [poly (dibenzo-18-crown-6) formaldehyde: manufactured by Aldrich] used in Example 8 was not added. An electrophotographic photosensitive member was manufactured.

The electrophotographic photosensitive member obtained as described above was evaluated for electrostatic characteristics in a dynamic mode using EPA 8200 (manufactured by Kawaguchi Electric Works). First, the photosensitive member is positively charged by performing a corona discharge of +5.3 KV for 5 seconds, and the surface potential V ₂ (+ V) after 2 seconds is measured. Further, when the surface potential becomes +800 V, a band pass filter is used. Light separated at 780 nm (5.0 μW / c
m ² ) was exposed, and the exposure E _1/2 (μJ / cm ² ) required for the surface potential to attenuate to +400 V and the surface potential Vr (+ V) 30 seconds after the exposure were measured. In addition, + 5.3KV
Was repeatedly performed 5000 times with a corona discharge and a tungsten lamp 45lux having a color temperature of 2856K, and then the same measurement was performed to evaluate the electrostatic characteristics after fatigue. Table 3 shows the evaluation results.

[0062]

[Table 3]

[0063]

As described above, an oxytitanyl phthalocyanine pigment is used as a charge generator on a conductive support.
By providing a photosensitive layer containing at least the pigment and a polycrown ether compound represented by the general formula (1), the photosensitive layer has good sensitivity to a semiconductor laser, has little change in chargeability even when used repeatedly, and has a residual potential. An electrophotographic photoreceptor having a small increase in the electric potential and having excellent potential stability can be obtained.

[Brief description of the drawings]

FIG. 1 is an X-ray diffraction spectrum of the amorphous oxytitanyl phthalocyanine pigment obtained in Synthesis Example 1.

FIG. 2 is an X-ray diffraction spectrum of the crystalline oxytitanyl phthalocyanine pigment obtained in Synthesis Example 2.

Claims (6)

[Claims] An oxytitanyl phthalocyanine pigment is used as a charge generating material on a conductive support, and a photosensitive layer containing at least the pigment and a polycrown ether compound represented by the following general formula (1) is provided. Electrophotographic photoreceptor. Embedded image In the formula, ring A and ring B each independently represent a benzene ring or a cyclohexyl ring. L and m each independently represent an integer of 0 to 3. 2. A charge-generating layer and a hole-transporting material comprising an oxytitanyl phthalocyanine pigment as a charge-generating material on a conductive support, the pigment and the polycrown ether compound represented by the general formula (1). A negatively-charged electrophotographic photosensitive member, comprising a charge transport layer containing 3. The negatively charged electrophotographic photoreceptor according to claim 2, wherein said hole transporting substance is a stilbene compound represented by the following general formula (2). . Embedded image In the formula, r ₁ and r ₂ are a substituted or unsubstituted alkyl group,
Represents a substituted or unsubstituted aryl group, and r ₃ and r ₄ are
Represents a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group or a heterocyclic group. Also,
r ₁ and r ₂ may form a ring. 4. An oxytitanyl phthalocyanine pigment is used as a charge-generating material on a conductive support, and a charge-generating layer and an electron-transporting material containing the pigment, the polycrown ether compound represented by the general formula (1) are used. A positively chargeable electrophotographic photoreceptor characterized in that a charge transport layer to be contained is laminated and provided in this order. 5. The positively charged electrophotographic photosensitive member according to claim 4, wherein the electron transporting substance is (2,3-diphenyl-1-indenylidene) malononitrile represented by the following formula (3). Positively charged electrophotographic photosensitive member. Embedded image 6. An electroconductive support comprising an oxytitanyl phthalocyanine pigment as a charge-generating substance, containing the pigment, an electron transporting substance or a hole transporting substance, and a polycrown ether compound represented by the above general formula (1). An electrophotographic photoreceptor comprising a single photosensitive layer.