JPH11305465A - Electrophotographic photoreceptor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrophotographic photoreceptor having good well- balanced electrification ability, sensitivity, dark attenuation, residual potential, environmental characteristics and repetitive characteristics. SOLUTION: Relating to an electrophotographic photoreceptor obtd. by forming a photosensitive layer on an electrically conductive substrate, a monoclinic dihydroxy-silicon phthalocyanine compd. having lattice constants a=12.8±1 Å, b=14.5±1 Å, c=6.8±1 Å and β=94.4±1 Å or a dihyroxy-silicon phthalocyanine compd. having peaks at 9.2 deg., 14.1 deg., 15.3 deg., 19.7 deg. and 27.1 deg. Bragg angles 2 θ(±0.3 deg.) in its X-ray diffraction spectrum is used as an electric charge generating material and a compd. having a stilbene skeleton is used as an electric charge transferring material.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic photoreceptor, and more particularly, to an electrophotographic photoreceptor having high sensitivity and excellent characteristics from a visible region to a near-infrared wavelength region. is there. Hereinafter, the electrophotographic photosensitive member is abbreviated as a photosensitive member.

[0002]

2. Description of the Related Art In recent years, laser light has been used as a light source to increase the speed,
2. Description of the Related Art Laser printers, which have advantages of high image quality and non-impact, have come into widespread use, and photoconductors capable of meeting the demands have been actively developed. In particular, a method using a semiconductor laser as a light source is mainly used, and the wavelength of the light source is 780 nm.
There is a strong demand for a photoreceptor having high sensitivity to long wavelength light before and after.

Under the circumstances described above, phthalocyanine compounds are (1) relatively easily synthesized;
(2) having an absorption peak in a long wavelength region of 600 nm or more; (3) the spectral sensitivity varies depending on the central metal and crystal form;
Several compounds exhibiting high sensitivity in the wavelength range of semiconductor lasers have been published, and research and development are being vigorously conducted.

In the case of phthalocyanine compounds such as copper phthalocyanine, α, γ, ε, π,
Crystal forms such as χ, τ, ρ, and δ are known, and these crystal forms can be mutually transferred by mechanical strain, sulfuric acid treatment, organic solvent treatment, heat treatment, etc. (Organic Electronics Materials Series) 6 "Phthalocyanine"). The absorption spectrum and photoconductivity of the phthalocyanine compound vary depending not only on the type of the central metal but also on the crystal form as described above. Are different.

Japanese Patent Application Laid-Open No. 50-38543 discloses that, with respect to the crystal form and electrophotographic properties of copper phthalocyanine, the ε form shows the highest sensitivity in comparison with the α, β, γ and ε forms. ing. On the other hand, as for hydroxymetal phthalocyanine, a photoreceptor using dihydroxygermanium phthalocyanine, dihydroxytin phthalocyanine or dihydroxysilicon phthalocyanine is described in U.S. Pat. No. 4,557,989. Japanese Patent Application Laid-Open No. 6-214415 also discloses hydroxymetal phthalocyanine (Al, Ga, In, Si, Ge, S
There is a report on an electrophotographic photoreceptor using n),
One crystal form has been proposed for dihydroxysilicon phthalocyanine.

[0006]

However, dihydroxysilicon phthalocyanine having a conventionally known crystal form has problems in dispersibility, applicability of a dispersion, and storage stability, and is not necessarily sufficient in electrophotographic characteristics. Absent. The present invention has been made in view of such circumstances, and its object is to provide a chargeability, sensitivity, dark decay, residual potential,
It is an object of the present invention to provide a photoreceptor having good environmental characteristics, good repetition characteristics, and the like and a good balance.

[0007]

Means for Solving the Problems As a result of diligent studies, the present inventor has found that if a novel crystalline dihydroxysilicon phthalocyanine is used as a charge generating material and a compound having a stilbene skeleton is used as a charge transporting material. For example, they have found that the above object can be easily achieved, and have completed the present invention.

That is, a first gist of the present invention is to provide an electrophotographic photoreceptor comprising a photosensitive layer formed on a conductive support, as a charge generation material, a monoclinic crystal having a lattice constant a =
12.8 ± 1Å, b = 14.5 ± 1Å, c = 6.8 ± 1Å, β = 94.4 ±
An electrophotographic photoreceptor characterized in that a dihydroxysilicon phthalocyanine compound having 1% is used and a compound having a stilbene skeleton is used as a charge transporting material.

A second gist of the present invention is to provide an electrophotographic photoreceptor having a photosensitive layer formed on a conductive support, as a charge generation material, in the X-ray diffraction spectrum, the Bragg angle 2θ (± 0.3 Ii) 9.2, 14.1, 15.3, 19.
An electrophotographic photoreceptor comprising a dihydroxysilicon phthalocyanine compound having a peak at 7, 27.1 °, and a compound having a stilbene skeleton as a charge transporting material.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail.
First, a charge generation material (a novel crystalline dihydroxysilicon phthalocyanine compound) and a charge transport material (a compound having a stilbene skeleton) in the photoreceptor of the present invention will be described.

The basic structure of the dihydroxysilicon phthalocyanine compound used in the present invention is represented by the following general formula (I).

[0012]

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The dihydroxysilicon phthalocyanine compound used in the present invention has the following characteristics. That is, (1) monoclinic and lattice constant a = 12.8 ± 1 °, b
= 14.5 ± 1 °, c = 6.8 ± 1 °, β = 94.4 ± 1 °.
(2) In the X-ray diffraction spectrum, as shown in FIG. 1, Bragg angles 2θ (± 0.3 °) 9.2, 14.1, 15.3, 19.
It has a peak at 7, 27.1 ゜. In addition, for example, 12.2, 23.
Although there are peaks at 1 and 23.4 °, the ratio and position of the peak intensity may slightly vary depending on the manufacturing conditions, the crystal orientation, the method of measuring the X-ray diffraction spectrum, and the like. In the above dihydroxy silicon phthalocyanine compound,
Alkyl, alkoxy and halogen atom substituted substrates may be included.

The above lattice constant is determined by measuring an X-ray diffraction spectrum under the following conditions and using the method of Ito et al. (Nature, 164, 755).
(1949), "X-ray Studies on Polymorphism", Maru
zen, Tokyo, 187).

[0015]

[Table 1] X-ray Cu Kα1 voltage 50KV current 250mA start angle 5.00deg stop angle 60.00deg step angle 0.01deg measurement time 10.00sec / step slit DS 1deg, SS 1deg, RS 0.1mm

The above X-ray diffraction spectrum was measured under the following conditions.

[0017]

[Table 2] X-ray Cu Kα1 voltage 40KV current 30mA Start angle 3.00deg Stop angle 40.00deg Step angle 0.05deg Measurement time 0.50sec / step Slit DS 1deg, SS 1deg, RS 0.2mm

The above-mentioned novel crystalline dihydroxysilicon phthalocyanine compound can be produced, for example, by the following method (1) or (2).

(1) First, after heating 1,3-diiminoisoindoline or phthalodinitrile and silicon tetrachloride in a solvent, the reaction product is filtered, washed and purified to obtain a dichlorosilicon phthalocyanine compound. Next, N-methylpyrrolidone, ethylene carbonate, propylene carbonate, N, N-dimethylformamide, N, N-dimethylacetamide, dimethyl sulfoxide, hydrolyze by heating in a polar solvent such as sulfolane to dihydroxy silicon phthalocyanine compound. obtain.

(2) First, a dichlorosilicon phthalocyanine compound is treated in the presence of an alcohol to obtain a dialkoxysilicon phthalocyanine compound. Next, by heating with a polar solvent in the same manner as described above, a dihydroxysilicon phthalocyanine compound is obtained.

On the other hand, the compound having a stilbene skeleton used in the present invention includes, for example, the following chemical formulas (1) to
The compound represented by (126) is mentioned.

The photoreceptor of the present invention comprises a photosensitive layer formed on a conductive support, and a charge generation material (dihydroxysilicon phthalocyanine compound) and a charge transport material (compound having a stilbene skeleton) in the photosensitive layer. And The photosensitive layer is usually configured as a laminated type, but may be a single layer (single layer) type.

The laminated photosensitive layer is formed by laminating a charge generation layer and a charge transport layer in an arbitrary order. The charge generation layer is formed by a vapor deposition method or a coating method using a dispersion of a charge generation material and a binder, and the charge transport layer is formed by a casting method from an organic solvent solution or the above-described coating method. On the other hand, the single-layer photosensitive layer is formed by a coating method using a dispersion of a charge generation material, a charge transport material, and a binder. And the photoreceptor of the present invention has an adhesive layer,
In addition to an intermediate layer such as a blocking layer, a protective layer for improving electric characteristics and mechanical characteristics may be provided.

Examples of the conductive support include metal drums and sheets of aluminum, copper, nickel and the like, and laminates and vapor-deposits of these metal foils. Furthermore, conductive materials (metal powder, carbon black, copper iodide, polymer electrolyte, etc.) are applied together with a suitable binder, and the conductive material is contained in addition to conductive films, plastic drums, paper, etc. And a plastic film having on its surface a layer of a conductive metal oxide (such as tin oxide or indium oxide).

The blocking layer is formed on the surface of the conductive support, and is effective in preventing unnecessary charge injection from the conductive support. Further, the blocking layer has an effect of increasing the charge of the photosensitive layer and also an effect of increasing the adhesion between the photosensitive layer and the conductive support.

Examples of the constituent materials of the blocking layer include aluminum anodic oxide films, aluminum oxide, aluminum hydroxide, titanium oxide, surface-treated titanium oxide and other inorganic substances, polyvinyl alcohol, casein, polyvinylpyrrolidone, polyacrylic acid, celluloses, gelatin. And organic layers of starch, polyurethanes, polyimides, polyamides, etc., and other organic zirconium compounds, titanium chelate compounds, titanium alkoxide compounds, organic titanium compounds, silane coupling agents, and the like. The thickness of the blocking layer is usually 0.1 to 20 mm,
Preferably it is in the range of 0.1 to 10 mm.

In the case of the laminated photosensitive layer, the charge generation layer formed by the coating method includes, in addition to the charge generation material and the binder,
If necessary, the composition contains an organic photoconductive compound, a coloring matter, and an electron-withdrawing compound.

Examples of the organic photoconductive compound include phthalocyanine compounds such as dialkoxy silicon phthalocyanine, titanyl phthalocyanine, gallium phthalocyanine, indium phthalocyanine, and metal-free phthalocyanine, azo compounds, anthraquinone compounds, perylene compounds, and polycyclic quinones. And methine squaric acid-based compounds.

Examples of the binder (binder resin) include vinyl compounds such as styrene, vinyl acetate, vinyl chloride, vinylidene chloride, acrylate, methacrylate, acrylamide, acrylonitrile, vinyl alcohol, ethyl vinyl ether and vinyl pyridine. Polymers and copolymers, phenoxy resins, polysulfone resins, polyvinyl acetal resins, polyvinyl butyral resins, polycarbonate resins, polyester resins,
Examples include polyamide resin, polyurethane resin, cellulose ester resin, cellulose ether resin, epoxy resin, silicon resin, alkyd resin, polyarylate resin, and the like.

The coating solution for the charge generation layer is prepared by dispersing (partially dissolving) the charge generation material in a binder solution. Examples of the organic solvent include ethers such as tetrahydrofuran, dioxane and ethylene glycol monomethyl ether; ketones such as acetone, methyl ethyl ketone and cyclohexanone; aromatic hydrocarbons such as toluene and xylene; halogenated aromatics such as monochlorobenzene and dichlorobenzene. Aliphatic hydrocarbons, methylene chloride, chloroform, carbon tetrachloride, dichloroethane, halogenated aliphatic hydrocarbons such as trichloroethane, methanol, ethanol, alcohols such as isopropanol, methyl acetate,
Esters such as ethyl acetate; amides such as N, N-dimethylformamide and N, N-dimethylacetamide; and sulfoxides such as dimethyl sulfoxide.

The ratio of the binder used is as follows.
It is usually in the range of 1 to 1000 parts by weight, preferably 10 to 400 parts by weight, based on 00 parts by weight. Examples of the dispersion method include a method using a ball mill, a sand grind mill, a planetary mill, a roll mill, a paint shaker, and the like.

Examples of the coating method include dip coating, spray coating, spinner coating, bead coating, wire bar coating, blade coating, roller coating, curtain coating, and ring coating.

Drying after coating is carried out, for example, at 25 to 250 ° C.
At a temperature of 5 minutes to 3 hours in a stationary or blown state. Further, the thickness of the formed charge generation layer is
Usually, the range of 0.1 to 5 mm is appropriate.

The charge transport layer of the laminated photosensitive layer contains, if necessary, additives such as an antioxidant in addition to the charge transport material and the binder. As the binder, the same insulating resin as described above can be used. The binder is used in an amount of usually 20 to 3000 parts by weight, preferably 50 to 1000 parts by weight, based on 100 parts by weight of the charge transporting material. The charge transport layer is formed by applying and drying a coating solution prepared using the same organic solvent as described above, and the thickness of the charge transport layer is usually in the range of 5 to 50 mm.

The photosensitive layer of the single-layer type photosensitive layer contains a charge generating material, a charge transporting material, and a binder. A charge generating substance other than the dihydroxysilicon phthalocyanine compound may be used in combination. As the binder, the same insulating resin as described above can be used. Further, if necessary, various additives such as an antioxidant and a sensitizer may be contained.

The binder is generally used in an amount of 2 to 300 parts by weight based on 10 parts by weight of the charge generating material and the charge transporting material, and the charge transporting material is generally used in an amount of 0.01 based on 1 part by weight of the charge generating material. A suitable range is from 100 to 100 parts by weight. The single-layer type photosensitive layer is formed by applying and drying a coating solution prepared using the same organic solvent as described above.

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[0061]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to the following examples unless it exceeds the gist of the present invention.

Synthesis Example 1 (Synthesis of dichlorosilicon phthalocyanine) 43.5 g of 1,3-diiminoisoindoline and 73.5 g of silicon tetrachloride were added to 500 ml of quinoline, and heated at 210 to 220 ° C. for 1 hour under a nitrogen atmosphere. Reacted. The product was hot-filtered at 180 ° C., and washed with quinoline and acetone in this order. Then, the mixture was heated under reflux in 300 ml of acetone, and the crystals were separated by filtration and dried to obtain 38.7 g of dichlorosilicon phthalocyanine.

The structural analysis was performed by mass spectrum (negative measurement), IR (KBr method), and elemental analysis. FIG. 2 shows a mass spectrum of dichlorosilicon phthalocyanine, and FIG. 3 shows an IR spectrum. M / z in mass spectrum:
At 610, a peak of dichlorosilicon phthalocyanine was confirmed. m / z: 575 is a fragment peak from which one chlorine atom has deviated.

In the IR spectrum, 1533, 1079, 1060 cm
^-1 showed an absorption characteristic of dichlorosilicon phthalocyanine (E. Cilibertoetal., J. Am. Chem. Soc., 106, 7748 (19
84)). The results of the elemental analysis are shown below, which are almost the same as the calculated values. As a result of structural analysis, the synthesized product was identified as dichlorosilicon phthalocyanine.

[0065]

Table 3 C (%) H (%) N (%) Si (%) Cl (%) Found 62.65 2.58 18.12 4.48 12.21 Calculated 62.85 2.62 18 .33 4.58 11.62

FIG. 4 shows an X-ray diffraction spectrum of the above-mentioned dichlorosilicon phthalocyanine. 2θ = 10.7, 12.3, 1
It has peaks at 5.5, 17.6, 19.9, 24.6, 26.8, and 27.6 °, respectively.

Synthesis Example 2 (Synthesis of dimethoxysilicon phthalocyanine) Dichlorosilicon phthalocyanine 1 synthesized in Synthesis Example 1
0 g of sodium methoxide 1.86 g, methanol 1
The mixture was added to a mixture of 00 ml and 100 ml of pyridine and reacted under reflux for 3 hours. The product is filtered hot, methanol,
Washing was performed in the order of water and acetone. Then, after repeating washing several times in 100 ml of water, the neutrality was confirmed, and the crystals were separated by filtration.
After drying, 9.7 g of dimethoxysilicon phthalocyanine was obtained.

The structural analysis was performed in the same manner as in Synthesis Example 1. FIG. 5 shows a mass spectrum of dimethoxysilicon phthalocyanine. In the mass spectrum, a peak of dimethoxysilicon phthalocyanine was confirmed at m / z: 602. m / z:
571 is a fragment peak from which one methoxy group has been removed. The results of the elemental analysis are shown below, which are almost the same as the calculated values. As a result of structural analysis, the synthesized product was identified as dimethoxysilicon phthalocyanine.

[0069]

Table 4 C (%) H (%) N (%) Si (%) Found 68.02 3.72 18.71 4.70 Calculated 67.78 3.65 18.60 4.65

FIG. 6 shows an X-ray diffraction spectrum of the above dimethoxysilicon phthalocyanine. 2θ = 8.1, 12.2,
It has peaks at 13.0, 17.0, 18.7, 23.3, 26.0, 27.8, and 30.4 °, respectively.

Synthesis Example 3 (Synthesis of dihydroxysilicon phthalocyanine) Dichlorosilicon phthalocyanine 1 synthesized in Synthesis Example 1
0 g, water 5 g and N-methylpyrrolidone 95 g (95% NMP
Aqueous solution) and reacted at 130 ° C. for 8 hours. The product was filtered hot and washed with NMP and acetone in this order. Then, after stirring at room temperature in 50 ml of acetone, the crystals were filtered off and dried to obtain dihydroxysilicon phthalocyanine.
4 g were obtained.

The structural analysis was performed in the same manner as in Synthesis Example 1. FIG.
Shows a mass spectrum of dihydroxysilicon phthalocyanine, and FIG. 8 shows an IR spectrum. In the mass spectrum, a peak of dihydroxysilicon phthalocyanine was confirmed at m / z: 574. m / z: 557 is a fragment peak from which one hydroxyl group has been removed. 15 in the IR spectrum
Absorption specific to dihydroxysilicon phthalocyanine was observed at 19, 1066, and 839 cm ^-1 (see the above paper). The results of the elemental analysis are shown below, which are almost the same as the calculated values. As a result of structural analysis, the compound was identified as dihydroxysilicon phthalocyanine.

[0073]

Table 5 C (%) H (%) N (%) Si (%) Cl (%) Found 62.70 3.10 19.10 4.94 0.03 Calculated 66.89 3.16 19 .50 4.89 0

The structural analysis of the above-mentioned dihydroxysilicon phthalocyanine was carried out according to the method of Ito. As a result, the dihydroxysilicon phthalocyanine was monoclinic and had lattice constants a = 12.78 °, b = 14.61 °, and c = 6.79.
Β, β = 94.4 ゜, and the X-ray diffraction spectrum (FIG. 1) has a main peak of 2 ゜ at 9.2 ゜.
Dihydroxysilicon phthalocyanine having peaks at 2.2, 14.0, 15.3, 19.7, 23.4, and 27.1 °, respectively.

Synthesis Example 4 (Synthesis of dihydroxysilicon phthalocyanine) 10 g of dimethoxysilicon phthalocyanine synthesized in Synthesis Example 2 was added to 200 g of N-methylpyrrolidone.
The reaction was performed at 0 ° C. for 2 hours. The product was subjected to hot filtration, and the same treatment was further repeated twice. The product was hot filtered, and washed with NMP and acetone in this order. Then, after stirring at room temperature in 100 ml of acetone, the crystals were separated by filtration and dried to obtain 8.0 g of dihydroxysilicon phthalocyanine. As a result of structural analysis by mass spectrum (negative measurement) and IR (KBr method), a spectrum similar to that of Synthesis Example 3 was obtained, and it was confirmed to be dihydroxysilicon phthalocyanine. The results of the elemental analysis are shown below, which are almost the same as the calculated values.

[0076]

Table 6 C (%) H (%) N (%) Si (%) Found 62.70 3.10 19.10 4.94 Calculated 66.89 3.16 19.50 4.89

The structural analysis of the above-mentioned dihydroxysilicon phthalocyanine was carried out according to the method of Ito. As a result, it was found that the dihydroxysilicon phthalocyanine was monoclinic, had lattice constants a = 12.82 °, b = 14.63 °, and c = 6.79.
Β, β = 94.4 ゜, and in the X-ray diffraction spectrum (FIG. 9), it had a main peak of 9.2 ゜ at 2θ, and 1
Dihydroxysilicon phthalocyanine having peaks at 2.2, 14.0, 15.3, 19.7, 23.4, and 27.1 °, respectively.

Synthesis Example 5 (Synthesis of dihydroxy silicon phthalocyanine) 10 g of dimethoxy silicon phthalocyanine synthesized in Synthesis Example 2 was mixed with 5 g of water and 95 g of N-methylpyrrolidone (95% NMP).
Aqueous solution) and reacted at 148 ° C. for 3 hours. The product was filtered hot and washed with NMP and acetone in this order. Then, after stirring in 100 ml of acetone at room temperature, the crystals are filtered off and dried to obtain dihydroxysilicon phthalocyanine.
0 g was obtained.

Mass spectrum (negative measurement), IR
As a result of structural analysis by (KBr method), a spectrum similar to that of Synthesis Example 3 was obtained, and it was confirmed to be dihydroxysilicon phthalocyanine. Structural analysis of the obtained dihydroxysilicon phthalocyanine was carried out according to the method of Ito. As a result, it was found that the obtained dihydroxysilicon phthalocyanine was monoclinic and had a lattice constant a of 12.79 ° and b of 14.61.
Å, c = 6.79Å, β = 94.4 ゜, and in the X-ray diffraction spectrum (FIG. 10), it had a main peak of 2 ゜ at 9.2 ゜, and others, 12.2, 14.0, 15.3, 19.7, 23.4, 27.1 ゜Of dihydroxysilicon phthalocyanine each having a peak at

Comparative Example Synthesis Example 1 (Prior Art 1: JBDavisi
on etal., Macromol., 1978, 11, 186) The dichlorosilicon phthalocyanine obtained in Synthesis Example 1 4.4.
g was added to a mixture of 1.1 g of NaOH, 100 ml of water and 26 ml of pyridine, and the mixture was reacted at reflux for 1 hour. The product was filtered hot and washed with pyridine, acetone and water in this order. Subsequently, stirring at room temperature was repeated several times in 50 ml of water, and after confirming neutrality, the crystals were separated by filtration and dried to obtain 3.2 g of dihydroxysilicon phthalocyanine.

Mass Spectrum (Negative Measurement) and IR
As a result of structural analysis by (KBr method), a peak of dihydroxysilicon phthalocyanine was confirmed at m / z: 574 in the mass spectrum, and dihydroxy at 1519, 1070 and 829 cm ^-1 in the IR spectrum as shown in FIG. Absorption unique to silicon phthalocyanine was observed, and it was confirmed to be dihydroxysilicon phthalocyanine. However, the dihydroxysilicon phthalocyanine obtained in the present synthesis example is different from the synthesis example 1
Compared with the dihydroxysilicon phthalocyanine obtained in Nos. To 5 (1066, absorption at 838 cm ^-1 ), there is a difference in the crystal form due to the shift in absorption. FIG. 12 shows the X of the dihydroxysilicon phthalocyanine obtained in this synthesis example.
2 shows a line diffraction spectrum. 2θ = 7.1, 9.3, 12.8, 15.
It has peaks at 8, 17.2, 25.6, and 26.9 °, respectively. As a result of the structural analysis, it was confirmed that the synthesized product of Comparative Example Synthesis Example 1 was dihydroxysilicon phthalocyanine whose lattice constant was clearly different from the dihydroxysilicon phthalocyanine defined in the present invention.

Comparative Synthesis Example 2 (Prior Art 2: JP-A-6-2
Synthesis Example 10 of No. 14415) 3 g of the dichlorosilicon phthalocyanine obtained in Synthesis Example 1 was dissolved in 80 g of concentrated sulfuric acid at 5 ° C., and then 450 g of water at 0 ° C.
Crystals were precipitated by dropping gradually into the mixture. Thereafter, the resultant was sequentially washed with water, diluted ammonia water and water, and dried to obtain 2.6 g of dihydroxysilicon phthalocyanine.

Mass Spectrum (Negative Measurement) and IR
As a result of structural analysis by (KBr method), a spectrum similar to that of dichlorosilicon phthalocyanine obtained in Synthesis Example 1 was obtained, and it was confirmed to be dihydroxysilicon phthalocyanine. 2.5 g of this dihydroxy silicon phthalocyanine
Was ball milled for 24 hours in 60 g of methylene chloride with 100 g of glass beads having a diameter of 1 mm and then separated.

Next, the resultant was washed with methylene chloride and dried to obtain 1.8 g of dihydroxysilicon phthalocyanine. FIG. 13 shows an X-ray diffraction spectrum of the obtained dihydroxysilicon phthalocyanine. 2θ = 7.0, 9.2, 1
It has peaks at 0.6, 12.7, 17.1, 25.6, and 26.6 °, respectively. As a result of the structural analysis, it was confirmed that the synthetic product of Comparative Synthesis Example 2 was dihydroxysilicon phthalocyanine whose lattice constant was clearly different from the dihydroxysilicon phthalocyanine defined in the present invention.

Example 1 0.4 g of dihydroxysilicone phthalocyanine produced in Synthesis Example 3 was pulverized together with 30 g of 4-methoxy-4-methylpentanone-2 by a sand grind mill for 6 hours, and subjected to fine particle dispersion treatment. Next, polyvinyl butyral (Denka Butyral # 6000C, manufactured by Denki Kagaku Kogyo KK)
0.1 g and phenoxy resin (Union Carbide Co., Ltd.)
(UCAR), 0.1 g of 4-methoxy-4-methylpentanone-2 solution (10%) to prepare a dispersion. This dispersion was applied onto a polyester film on which aluminum was deposited by a bar coater and dried to form a charge generation layer (film thickness after drying: 0.4 mm). Next, on this charge generation layer, the following stilbene compound (a) 7.
A solution in which 0 g and 10 g of a polycarbonate resin were dissolved in 62 g of THF was applied by an applicator and dried to form a charge transport layer (film thickness after drying: 20 mm).

Examples 2 to 4 and Comparative Example 1 Photoconductors were prepared in the same manner as in Example 1 except that the charge generating materials and stilbene compounds shown in Table 7 below were used. In Table 7, (a) and (b) represent the following stilbene compounds.

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[Table 7]

Next, using an electrostatic copying paper tester ("Model EPA-8100" manufactured by Kawaguchi Electric Works), the initial electric characteristics (charging potential, dark decay, half-exposure sensitivity,
(Residual potential). As an evaluation method, the photoreceptor is negatively charged by corona discharge at an applied voltage set so that the corona current becomes 22 mA in a dark place (the surface potential at this time is referred to as a charged potential). Monochromatic light (1.0mW
/ cm ² ) was continuously exposed for 10 seconds and the decay of the surface potential was measured (the surface potential after 10 seconds of exposure was defined as the residual potential). The dark decay was defined as a potential which decreased one second after charging, and the half-exposure sensitivity was determined by the exposure (E1 / 2) required for the surface potential to decrease from -450 V to -225 V. Table 8 shows the results.

[0090]

[Table 8]

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According to the present invention described above, an electrophotographic photoreceptor having particularly excellent sensitivity characteristics and charge retention is provided. The electrophotographic photoreceptor of the present invention is effectively used for printers, facsimile machines, and copiers. It can be suitably used.

[Brief description of the drawings]

FIG. 1 is an X-ray diffraction diagram of a dihydroxysilicon phthalocyanine compound obtained in Synthesis Example 3.

FIG. 2 is a mass spectrum diagram of the dichlorosilicon phthalocyanine compound obtained in Synthesis Example 1.

FIG. 3 is an IR spectrum of the dichlorosilicon phthalocyanine compound obtained in Synthesis Example 1.

FIG. 4 is an X-ray diffraction diagram of the dichlorosilicon phthalocyanine compound obtained in Synthesis Example 1.

FIG. 5 is a mass spectrum diagram of the dimethoxysilicon phthalocyanine compound obtained in Synthesis Example 2.

FIG. 6 is an X-ray diffraction diagram of the dimethoxysilicon phthalocyanine compound obtained in Synthesis Example 2.

FIG. 7 is a mass spectrum diagram of the dihydroxysilicon phthalocyanine compound obtained in Synthesis Example 3.

FIG. 8 is an IR spectrum of the dihydroxysilicon phthalocyanine compound obtained in Synthesis Example 3.

FIG. 9 is an X-ray diffraction diagram of the dihydroxysilicon phthalocyanine compound obtained in Synthesis Example 4.

FIG. 10 is an X-ray diffraction diagram of the dihydroxysilicon phthalocyanine compound obtained in Synthesis Example 5.

FIG. 11 is an IR spectrum of the dihydroxysilicon phthalocyanine compound obtained in Comparative Synthesis Example 1.

FIG. 12 is an X-ray diffraction diagram of the dihydroxysilicon phthalocyanine compound obtained in Comparative Synthesis Example 1.

FIG. 13 is an X-ray diffraction diagram of the dihydroxysilicon phthalocyanine compound obtained in Comparative Synthesis Example 2.

Claims (2)

[Claims] 1. An electrophotographic photoreceptor comprising a photosensitive layer formed on a conductive support, wherein the charge generating material is monoclinic and has a lattice constant a = 12.8 ± 1 °, b = 14.5 ± 1 °, c =
An electrophotographic photoreceptor comprising a dihydroxysilicon phthalocyanine compound having 6.8 ± 1 ° and β = 94.4 ± 1 °, and a compound having a stilbene skeleton as a charge transporting material. 2. An electrophotographic photoreceptor comprising a photosensitive layer formed on a conductive support, wherein, as a charge generating material, a Bragg angle 2θ (± 0.3 °) in an X-ray diffraction spectrum.
An electrophotographic photoreceptor comprising a dihydroxysilicon phthalocyanine compound having peaks at 2, 14.1, 15.3, 19.7, and 27.1 °, and a compound having a stilbene skeleton as a charge transporting material.