JP2003005399A - Electrophotographic photoreceptor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrophotographic photoreceptor capable of forming an image from the first rotation and less liable to double charging. SOLUTION: In the electrophotographic photoreceptor obtained by stacking an electric charge generating layer 3 and an electric charge transporting layer 4 on an electrically conductive support 1, the electric charge generating layer 3 contains a phthalocyanine composition and a diphenoquinone derivative.

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 mounted on an electrophotographic apparatus (printer, copying machine, etc.) by the Carlson method.

[0002]

2. Description of the Related Art Conventionally, electrophotographic photoconductors mounted on an electrophotographic apparatus (printer, copier, etc.) by the Carlson method include selenium, zinc oxide, titanium oxide, cadmium oxide,
Inorganic photoconductive materials such as amorphous silicon have been mainly used. However, in recent years, organic photoconductive materials, which are excellent in terms of safety and manufacturing cost, have become the mainstream. Among them, the laminated electrophotographic photosensitive member in which the functions of charge generation and charge transport are separated is currently being mass-produced because of the sensitizing action and high material selectivity due to the separated functions.

The charge generating material of the laminated type photoreceptor is 780 nm which is a semiconductor laser oscillation wavelength and 660 which is an LED light.
It has been widely studied to use a phthalocyanine compound that has sensitivity to near infrared light such as nm and is relatively easy to synthesize,
It has been put to practical use. Phthalocyanine compounds differ not only in their absorption spectra and photoconductivity depending on the type of central metal, but also in their physical properties depending on the crystal type. Several examples have been reported that have been selected for photoreceptors.

For example, various crystal forms of titanyl phthalocyanine exist, and it has been reported that there are large differences in chargeability, darkness and sensitivity due to the difference in the crystal forms.
Japanese Unexamined Patent Publication No. 59-49544 discloses a crystal form of titanyl phthalocyanine which has a Bragg angle (2θ ± 0.2).
Degree) is 9.2 degrees, 13.1 degrees, 20.7 degrees, 26.2 degrees
It is described that a substance giving a strong diffraction peak at 27.1 degrees is suitable, and its X-ray diffraction spectrum diagram is shown. Japanese Unexamined Patent Publication No. 59-166959 discloses a film in which a vapor-deposited film of titanyl phthalocyanine is left in saturated steam of tetrahydrofuran for 1 to 24 hours to change its crystal form to form a charge generation layer. The X-ray diffraction spectrum has a small number of peaks and a wide width, and has black angles (2θ) of 7.5 degrees, 12.6 degrees, 13.0 degrees,
It has been shown to give strong diffraction peaks at 25.4, 26.2 and 28.6 degrees. Japanese Patent Laid-Open No. 64-1706
No. 6, as a crystal form of titanyl phthalocyanine, a main peak of Bragg angle (2θ ± 0.2 degrees) is at least 9.5 degrees, 9.7 degrees, 11.7 degrees, 15.0 degrees, 2
Those having 3.5 degrees, 24.1 degrees and 27.3 degrees are described as being suitable. In JP-A-2-131243 and JP-A-2-214867, the crystal form of titanyl phthalocyanine has a Bragg angle of 27.
Those having a main diffraction peak at 3 degrees are described as being suitable.

An electrophotographic photosensitive member using such a phthalocyanine compound as a charge generating material for a charge generating layer has high sensitivity to near infrared light and has excellent characteristics. A phenomenon called double charge occurs in which the charging potential of the first rotation is lower than the charging potential of the second and subsequent rotations when the charging is performed by the above method. Due to this phenomenon, in reversal development, fog is likely to occur in the first rotation, and the gradation of the image changes between the first rotation and the second rotation. Therefore, a process design is generally used in which the data processing time is used to perform warming up for one rotation or more, and image formation is performed after the charging potential is stabilized.

However, in recent years, the data processing time has been greatly shortened as the operation speed and the like have been greatly improved.
An image is formed from the first rotation without warming up,
There is a market demand to reduce the first copy speed,
There is a demand for electrophotographic photoconductors with a low double charge.

[0007]

The inventions described in claims 1 to 3 provide an electrophotographic photosensitive member with a small double charge capable of forming an image from the first rotation.

[0008]

The present invention relates to the following. (1) An electrophotographic photoreceptor having a charge generating layer and a charge transport layer laminated on a conductive support, wherein the charge generating layer contains a phthalocyanine composition and a diphenoquinone derivative. (2) The phthalocyanine composition contains titanyl phthalocyanine and chloroindium phthalocyanine, and Cu
In the X-ray diffraction spectrum of Kα, the Bragg angle (2θ
The electrophotographic photosensitive member according to (1) or (2), which has major diffraction peaks at 17.9 degrees, 24.0 degrees, 26.2 degrees and 27.2 degrees (± 0.2 degrees). (3) The phthalocyanine composition contains titanyl phthalocyanine and chloroindium phthalocyanine, and Cu
In the X-ray diffraction spectrum of Kα, the Bragg angle (2θ
The electrophotographic photosensitive member according to (1) or (2), which has main diffraction peaks at 7.5 °, 24.2 ° and 27.3 ° (± 0.2 °).

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail below.
FIG. 1 is a sectional view showing an embodiment of the electrophotographic photosensitive member according to the present invention. In FIG. 1, a conductive support 1, an undercoat layer 2 applied on the conductive support 1, a charge generation layer 3 applied on the undercoat layer 2, and a charge generation layer 3 applied on the charge generation layer 3. And a charge transport layer 4.

A material having sufficient conductivity is suitable for the conductive support. For example, a drum, sheet, belt or the like made of a metal such as aluminum, titanium, copper, nickel, zinc or chromium or an alloy thereof can be used. In addition, metals such as aluminum, copper, gold, silver, platinum, palladium, and metal oxides such as tin oxide and indium oxide are deposited on insulators such as plastic, glass, and paper, and carbon black and metal powder are bonded. It is possible to use a drum, sheet, belt or the like that has been subjected to a conductive treatment by dispersing and applying it on the resin to be coated.

An undercoat layer may be provided in order to prevent charges from being injected from the conductive support to the charge generation layer and to improve the adhesion of the charge generation layer to the conductive support. Good. As the undercoat layer, polyamide, polyvinyl alcohol, polyvinyl butyral, polyurethane,
A known resin film such as polyacrylic acid, polyimide, polycarbonate, polyester, polyethylene, or epoxy resin can be used. It can also be formed by a resin film in which conductive or semiconductive fine particles of metal or metal oxide are dispersed in these resins, or an anodized film such as alumite. The thickness of the undercoat layer is preferably 0.01 to 20 μm,
More preferably, it is from 05 to 5 μm.

The charge generation layer is formed by dispersing the charge generation material and the charge generation material in a binder resin. A phthalocyanine composition is used as the charge generation material. As the binder resin forming the charge generation layer, polyvinyl chloride, polyvinyl acetate, polyester, vinyl chloride-vinyl acetate copolymer, polyvinyl butyral, polyvinyl acetal,
Polystyrene, polycarbonate, acrylic resin, phenol resin, phenoxy resin, epoxy resin, melamine resin and the like are used. These resins may be used alone or as a mixture. Solvents for the coating liquid used when forming the charge generation layer from these resins include toluene, methylene chloride, monochlorobenzene, methyl alcohol, ethyl alcohol, ethyl acetate, tetrahydrofuran, cyclohexane and the like. These solvents may also be used alone or as a mixture. The thickness of the charge generation layer is 0.05 to 5 μm
And preferably 0.1 to 2 μm. As a method of dispersing the charge generating material and the diphenoquinone derivative in the coating liquid when producing the coating liquid for forming the charge generating layer, a ball mill, a sand mill,
Paint shaker, homomixer, homogenizer,
Known methods such as a disperser, a micronizer, and an ultrasonic wave can be used.

The diphenoquinone derivative in the present invention is
The diphenoquinone derivative can be used alone or as a blend of two or more kinds. less than,
Specific examples of the diphenoquinone derivative are shown below.

[0014]

[Chemical 1]

[0015]

[Chemical 2]

[0016]

[Chemical 3]

[0017]

[Chemical 4]

[0018]

[Chemical 5]

[0019]

[Chemical 6]

[0020]

[Chemical 7]

When the diphenoquinone derivative is contained in the charge generation layer, it is added to the phthalocyanine composition in an amount of 5 to 5.
It is preferably 200% by weight, more preferably 10 to 100% by weight. If it is less than 5% by weight, the double-charge preventing effect tends to be small, and if it exceeds 100% by weight, the sensitivity tends to be significantly lowered. Further, an electrophotographic photoreceptor containing a phthalocyanine crystal produced by adding a diphenoquinone derivative during the pigmentation step of the phthalocyanine composition as a charge generating material, rather than simply adding the diphenoquinone derivative to the charge generating layer, is extremely high. It shows sensitivity, but the double charge prevention effect is less.

The phthalocyanine composition in the present invention is not particularly limited, and known ones may be used. The phthalocyanine composition is prepared by precipitating a mixture of titanyl phthalocyanine and chloroindium phthalocyanine in water by an acid pasting method. , CuKα X-ray diffraction spectrum, Bragg angle (2θ ± 0.2 degrees)
A precipitate obtained by obtaining a precipitate having a characteristic diffraction peak at 27.2 degrees and subsequently treating the precipitate in a mixed solvent of an aromatic organic solvent and water is preferably used. It

In general, the phthalocyanine mixture is simply a physical mixture of two or more kinds of phthalocyanines used as the raw material, and the X-ray diffraction pattern of the phthalocyanine mixture has a peak pattern of each phthalocyanine simple substance used as the raw material. It consists of overlapping.
On the other hand, the phthalocyanine composition in the present invention is a mixture of titanyl phthalocyanine and chloroindium phthalocyanine at the molecular level, and the X-ray diffraction pattern is different from the superposition of peak patterns of the individual phthalocyanines used as raw materials. It shows a pattern.

The above-mentioned titanyl phthalocyanine can be obtained according to the description of JP-A-3-71144,
For example, it can be manufactured as follows. 18.4 g (0.144 mol) of phthalonitrile is added to 120 ml of α-chloronaphthalene, and then 4 ml (0.0364 mol) of titanium tetrachloride is added dropwise under a nitrogen atmosphere. After the dropping, the temperature is raised and the mixture is reacted with stirring at 200 to 220 ° C. for 3 hours, filtered while hot at 100 to 130 ° C., and washed with α-chloronaphthalene and then with methanol. 140 ml
Hydrolyze (90 ℃, 1 hour) with the ion-exchanged water of
This procedure is repeated until the solution becomes neutral and then washed with methanol. Then, it is thoroughly washed with N-methylpyrrolidone heated to 100 ° C., followed by washing with methanol. The compound thus obtained is dried under vacuum at 60 ° C. to obtain titanyl phthalocyanine. (Yield 46%).

The above-mentioned method for synthesizing chloroindium phthalocyanine is based on the inorganic chemistry [Ino
organic / Chemistry19, 3131 (1
980)] and JP-A-59-44054. Chloroindium phthalocyanine can be produced, for example, as follows. Phtharonitrile 78.2 mmol and trichloroindium 15.
Quinoline 100m purified by distilling 8 mmol twice
After being placed in 1 and heated under reflux for 0.5 to 3 hours,
After cooling to room temperature, it is filtered, washed with toluene, acetone, and then with methanol, further washed with methanol using a Soxhlet extractor, and then dried under vacuum heating at 60 ° C. to obtain chloroindium phthalocyanine. it can.

The composition ratio of titanyl phthalocyanine and chloroindium phthalocyanine used for producing the above phthalocyanine composition is such that the content of titanyl phthalocyanine is 20 to 95% by weight from the viewpoint of electrophotographic characteristics such as charging property, dark decay and sensitivity. %, Preferably 5
It is more preferably in the range of 0 to 90% by weight, and 65
To 90% by weight is particularly preferred, 75 to 90% by weight
Most preferably, it is within the range. If the content of titanyl phthalocyanine is less than 20% by weight, the sensitivity may decrease, and if it exceeds 95% by weight, the dark attenuation rate may decrease. In the production of the above-mentioned preferred phthalocyanine composition, first, a mixture of titanyl phthalocyanine and chloroindium phthalocyanine is precipitated in water by the acid pasting method to make it amorphous. Amorphization by the acid pasting method can be suitably performed as follows, for example.

First, 1 g of the phthalocyanine mixture was dissolved in 50 ml of concentrated sulfuric acid, stirred at room temperature, and then added dropwise to 1 liter of ion-exchanged water cooled with ice water in about 1 hour, preferably 40 to 50 minutes. The precipitate is collected by filtration. After that, it is washed with ion-exchanged water, and the pH of the wash water after washing is preferably pH 2 to 5, more preferably pH 3 and the conductivity is 5 to 500 μS /
The precipitate was repeatedly washed until it reached cm, then thoroughly washed with methanol, and then dried by heating under vacuum at 60 ° C.
An amorphous powder is obtained.

The powder of the precipitate composed of titanyl phthalocyanine and chloroindium phthalocyanine thus produced showed a clear Bragg angle (2θ ± 0.2 degrees) of 27.2 degrees in the X-ray diffraction spectrum of CuKα. Except for the diffraction peak, the peak is broad and its value cannot be clearly defined. When the pH of the washing water after the washing exceeds 5, the Bragg angle (2θ ± 0.2 in the X-ray diffraction spectrum of CuKα).
27.2 degree characteristic peak intensity decreases, and a new peak stronger than the peak intensity of 27.2 degree occurs at 6.8 degree. This powder is used as a mixed solvent of an aromatic organic solvent and water. The phthalocyanine composition in the present invention tends not to be obtained even when crystal conversion is performed using, and when the pH of the wash water after washing is less than 2 or more than 5, the chargeability, the dark decay rate, Sensitivity tends to be poor. If the conductivity of the wash water after washing is less than 5 μS / cm or more than 50 μS / cm, the chargeability, dark decay rate, sensitivity, etc. tend to be poor.

Then, the powder of the precipitate (amorphized phthalocyanine) obtained above is treated in a mixed solvent of an aromatic organic solvent and water to convert the crystal form, whereby the present invention A phthalocyanine composition suitable for can be obtained.

Examples of the organic solvent used at the time of converting the crystal form in the mixed solvent of an aromatic organic solvent and water include benzene, toluene, xylene and o-dichlorobenzene. At this time, the ratio of aromatic organic solvent and water used is 1/99 to 99 of aromatic organic solvent / water.
/ (Weight ratio) is preferably 95/5 to 5 /
More preferably, it is 95. The crystal form conversion treatment in a mixed solvent of an aromatic organic solvent and water is, for example, 40 ° C.
To 100 ° C., preferably 60 to 80 ° C., 100 parts by weight of the total amount of the mixed solvent of the aromatic organic solvent and water is added to the precipitate 1
It can be carried out by contacting with 5 parts by weight for 1 to 24 hours.

As a method of contacting the precipitate with the mixed solvent, heating and stirring, or crushing and heating and stirring at the same time are carried out to obtain stable electrophotography when used as a charge generating material for an electrophotographic photoreceptor. The characteristics can be obtained. Examples of the method of simultaneously performing pulverization and heating and stirring include heating milling treatment, homogenizing, paint shaking, and the like. Among them, the heating milling treatment is preferable from the viewpoint that more stable electrophotographic characteristics can be obtained. As a medium used for crushing treatment such as heat milling treatment, for example, beads using a material having a specific gravity of 3 or more such as zirconia beads and alumina beads are preferable, and the diameter of the beads is preferably 0.2 to 3 mm. Preferably, it is more preferably φ 0.5 to 2 mm, and φ
Particularly preferably, it is 0.8 to 1.5 mm.

For example, the treatment with concentrated sulfuric acid of the phthalocyanine mixture in the previous step is performed with a blending ratio of the phthalocyanine mixture / concentrated sulfuric acid of 0.015 or less, and then the crystal form conversion treatment of the precipitate (amorphized phthalocyanine). In an X-ray diffraction spectrum of CuKα, the Bragg angle (2θ ± 0.2 °) of 17.9 ° and 24. A phthalocyanine composition having major diffraction peaks at 0 °, 26.2 ° and 27.2 ° is obtained.

Further, the treatment of the phthalocyanine mixture with concentrated sulfuric acid in the previous step is performed with a compounding ratio of the phthalocyanine mixture / concentrated sulfuric acid of 0.015 or less, and then the crystal form conversion of the precipitate (amorphous phthalocyanine). By performing the treatment by heating and stirring in a mixed solvent of an aromatic organic solvent and water, the Bragg angle (2θ ± 0.2 °) of 7.5 in the X-ray diffraction spectrum of CuKα.
A phthalocyanine composition having major diffraction peaks at degrees, 24.2 degrees and 27.3 degrees is obtained.

In the X-ray diffraction spectrum of CuKα, the phthalocyanine composition of the present invention has a Bragg angle (2θ ± 0.2 °) of 17.9 °, 24.0 °, and 24.0 °.
It is effective to use those having major diffraction peaks at 6.2 degrees and 27.2 degrees or those having major diffraction peaks at 7.5 degrees, 24.2 degrees and 27.3 degrees.

If necessary, the charge generating material containing the phthalocyanine composition of the present invention may be used in combination with a charge generating material other than the phthalocyanine composition as long as the characteristics of the electrophotographic photoreceptor of the present invention are not deteriorated. be able to.

Examples of charge generating materials (organic pigments that generate charges) other than the phthalocyanine composition include azoxybenzene-based, disazo-based, trisazo-based, benzimidazole-based, polycyclic quinone-based, indigoid-based, and anthanthrone-based materials. , Quinacridone type pigments, perylene type pigments, methine type pigments and the like which are known to generate electric charges.

The charge transport layer is formed by dissolving the charge transport material in the binder resin. Examples of the charge transport material include polymer compounds such as poly-N-vinylcarbazole, halogenated poly-N-vinylcarbazole, polyvinylpyrene, polyvinylindroquinoxaline, polyvinylbenzothiophene, polyvinylanthracene, polyvinylacridine, and polyvinylpyrazoline. And low molecular compounds include fluorenone, fluorene, 2,
7-Dinitro-9-fluorenone, 4H-indeno (1,2,6) thiophen-4-one, 3,7-dinitro-dibenzothiophen-5-oxide, 1-bromopyrene, 2-phenylpyrene, carbazole, N -Ethylcarbazole, 3-phenylcarbazole, 3- (N
-Methyl-N-phenylhydrazone) methyl-9-ethylcarbazole, 2-phenylindole, 2-phenylnaphthalene, oxadiazole, 2,5-bis (4-
Diethylaminophenyl) -1,3,4-oxadiazole, 1-phenyl-3- (4-diethylaminostyryl) -5- (4-diethylaminostyryl) -5- (4
-Diethylaminophenyl) pyrazoline, 1-phenyl-3- (p-diethylaminophenyl) pyrazoline, p
-(Dimethylamino) -stilbene, 2- (4-dipropylaminophenyl) -4- (4-dimethylaminophenyl) -5- (2-chlorophenyl) -1,3-oxazole, 2- (4-dimethylamino) Phenyl) -4-
(4-Dimethylaminophenyl) -5- (2-fluorophenyl) -1,3-oxazole, 2- (4-diethylaminophenyl) -4- (4-dimethylaminophenyl) -5- (2-fluorophenyl) -1,3-Oxazole, 2- (4-dipropylaminophenyl) -4-
There are (4-dimethylaminophenyl) -5- (2-fluorophenyl) -1,3-oxazole, imidazole, chrysene, tetraphene, aclidene, triphenylamine, benzidine, derivatives thereof, and the like, and known charge transports thereof. The materials may be used alone or in combination of two or more.

Binder resins usable in the charge transport layer include silicone resins, polyamide resins, polyurethane resins, polyester resins, epoxy resins, polyketone resins, polycarbonate resins, polyacrylic resins, polystyrene resins, styrene-butadiene copolymers. , Polymethylmethacrylate resin, polyvinyl chloride, ethylene-vinyl acetate copolymer, vinyl chloride-vinyl acetate copolymer,
Examples thereof include polyacrylamide resin, polyvinylcarbazole, polyvinylpyrazoline, polyvinylpyrene and the like. Further, a thermosetting resin and a photocuring resin which are crosslinked by heat and / or light can also be used. In any case, there is no particular limitation as long as it is an insulating resin capable of forming a coating film in a normal state and a resin which is cured by heat and / or light to form a coating film. These resins are used alone or as a mixture.

Further, various additives usually used, such as an ultraviolet absorber and an antioxidant, can be appropriately added to these resins. Tetrahydrofuran, dioxane, cyclohexane, toluene, dichloroethane, methylene chloride, monochlorobenzene and the like can be used as the solvent of the coating liquid when the charge transport layer is formed of these resins. These solvents can also be used alone or in combination.
The thickness of the charge transport layer is preferably 5 to 40 μm, more preferably 15 to 30 μm.

If necessary, additives such as a plasticizer, a fluidity imparting agent and a pinhole suppressor can be added to the coating liquid for the charge generating layer and the coating liquid for the charge transporting layer. Examples of the plasticizer include halogenated paraffin, dimethylnaphthalene, dibutyl phthalate, and the like, and as the fluidity-imparting agent,
Examples include Modaflow (manufactured by Monsanto Chemical Co., Ltd.) and Acronal 4F (manufactured by Basuf Co.), and examples of the pinhole inhibitor include benzoin and dimethyl phthalate. These may be appropriately selected and used, and the amount thereof may be appropriately determined.

As a method for forming the charge generation layer or the charge transport layer with a coating solution, known methods such as spin coating, dipping, roll coating, applicator coating and wire bar coating can be used. The applied charge generation layer or charge transport layer is dried by heating with hot air, infrared rays, or the like or holding under vacuum. The electrophotographic photosensitive member of the present invention may have a protective layer on the surface from the viewpoint of abrasion resistance.

[0042]

EXAMPLES Next, the present invention will be described in detail with reference to examples, but the present invention is not limited thereto.

Production Example 1 [Preparation of Phthalocyanine Composition (I)] 36 g of titanyl phthalocyanine and 12 indium phthalocyanine chloride.
48 g of a phthalocyanine mixture consisting of g
After dissolving in liter and stirring at room temperature for 30 minutes, this was added dropwise to 48 liters of ion-exchanged water cooled with ice water over 50 minutes to reprecipitate. Furthermore, after stirring for 30 minutes under cooling, the precipitate was separated by filtration. As the first washing, 4 liters of ion-exchanged water was added to the precipitate as washing water, the mixture was stirred, and then the precipitate was collected by filtration. Repeat the same washing operation 4 times in succession, and
In the second operation, the pH and conductivity of the filtered wash water (that is, wash water after washing) were measured (23 ° C.). The pH of the wash water was 3.4 and the conductivity was 65.0 μS / cm. In addition, for the measurement of pH, Model PH manufactured by Yokogawa Electric Corporation
51 was used, and the conductivity was measured using a model SC-17A manufactured by Shibata Scientific Instruments Co., Ltd. After this, methanol 4
After washing 3 times with liter, vacuum heating and drying was performed at 60 ° C. for 4 hours, and the obtained precipitate was dried. The obtained dried product X
As a result of measuring the line diffraction spectrum, the Bragg angle (2θ ±
(0.2 degree) showed a clear peak at 27.2 degrees.
The X-ray diffraction spectrum is RAD manufactured by Rigaku Denki Co., Ltd.
-Measured using IIIA. Then, this dried product 1
To 0 g, add 700 g of ion-exchanged water, 250 g of toluene and 1 kg of 1 mmφ zirconia beads, and add 60 to 70 ° C.
Mill for 5 hours and heat and stir it. After cooling, filter and centrifuge to remove the solvent, wash thoroughly with methanol,
The crystals were vacuum dried at 0 ° C. for 4 hours to obtain crystals of the phthalocyanine composition (I). As a result of measuring the X-ray diffraction spectrum of the obtained crystal of the phthalocyanine composition (I), the Bragg angle (2θ ± 0.2 degrees) was 17.9 degrees and 24.0 degrees.
The main diffraction peaks were shown at 26.2 degrees and 27.2 degrees. The X-ray diffraction spectrum is shown in FIG.

Production Example 2 [Preparation of Phthalocyanine Composition (II)] The precipitate was dried in the same manner as in Production Example 1, and 2 g of this dried product was added with 140 g of ion-exchanged water and 50 g of toluene to give a mixture of 60 to 70.
After heating and stirring at 5 ° C for 5 hours, centrifugation was performed, the supernatant was removed, the mixture was thoroughly washed with methanol, and dried by heating under vacuum at 60 ° C for 4 hours to obtain crystals of the phthalocyanine composition (II). X of the crystal of the obtained phthalocyanine composition (II)
As a result of measuring the line diffraction spectrum, the Bragg angle (2θ ±
The main diffraction peaks were shown at 7.5 degrees, 24.2 degrees and 27.3 degrees (0.2 degrees). The X-ray diffraction spectrum is shown in FIG.

Production Example 3 [Preparation of Phthalocyanine Composition (III)] 48 g of a phthalocyanine mixture and the diphenoquinone derivative (7) 1
6 g were mixed and dissolved in 2.4 liters of sulfuric acid,
A phthalocyanine composition was produced in the same manner as in Production Example 1. As a result of measuring the X-ray diffraction spectrum of the obtained crystal of the phthalocyanine composition (III), the same spectrum diagram as that of the phthalocyanine composition (I) was shown.

Example 1 [Formation of undercoat layer] 26.6 parts by weight of alcohol-soluble polyamide resin (M1276 manufactured by Nippon Rilsan Co., Ltd.), melamine resin (ML2000 manufactured by Hitachi Chemical Co., Ltd., solid content 50) % By weight) and 2.8 parts by weight of trimellitic anhydride (manufactured by Wako Pure Chemical Industries, Ltd.), 620 parts by weight of ethanol and 930 of 1,1,2-trichloroethane.
A coating solution was prepared by dissolving in parts by weight. The obtained coating liquid is applied onto a cylindrical aluminum support by a dip coating method and dried at 140 ° C. for 30 minutes to give a thickness of 0.3 μm.
m undercoat layer was formed.

[Formation of Charge Generation Layer] 9 parts by weight of the phthalocyanine composition (I) obtained in Production Example 1, 3 parts by weight of the diphenoquinone derivative (7), polyvinyl butyral resin (Sekisui Chemical Co., Ltd .: S-REC BL) -S) 12 parts by weight, 250 parts by weight of 2-ethoxyethanol and 250 parts by weight of tetrahydrofuran were mixed and dispersed in a ball mill for 20 hours. The thus-obtained coating liquid for charge generation layer was applied onto the undercoat layer of the above aluminum support by a dipping method and dried at 120 ° C. for 1 hour to give a thickness of 0.2 μm.
The charge generation layer of was formed.

[Formation of Charge Transport Layer] Next, the following formula (I
15 parts by weight of the charge-transporting material represented by I) and a polycarbonate resin (manufactured by Mitsubishi Gas Chemical Co., Inc .: Iupilon S-300).
0) 15 parts by weight of methylene chloride was dissolved in 155 parts by weight of methylene chloride to obtain a charge transport layer coating solution, which was applied onto the above charge generating layer by a dipping method and dried at 120 ° C. for 1 hour to give a thickness of 20.
A μm charge transport layer was formed to obtain an electrophotographic photoreceptor.

[0049]

[Chemical 8]

Example 2 Example 1 was repeated except that 6 parts by weight of the phthalocyanine composition (I) and 6 parts by weight of the diphenoquinone derivative (7) were used.
A photoconductor was prepared in the same manner as in.

Example 3 A photoconductor was prepared in the same manner as in Example 1 except that the phthalocyanine composition (II) obtained in Production Example 2 was used instead of the phthalocyanine composition.

Example 4 Example 1 was repeated except that 9 parts by weight of the phthalocyanine composition (I) and 3 parts by weight of the diphenoquinone derivative (2) were used.
A photoconductor was prepared in the same manner as in.

Example 5 12 parts by weight of phthalocyanine composition (III), polyvinyl butyral resin (Sekisui Chemical Co., Ltd .: S-REC B)
(LS) (12 parts by weight), 2-ethoxyethanol (250 parts by weight) and tetrahydrofuran (250 parts by weight) were mixed and dispersed in a ball mill for 20 hours. A photoconductor was manufactured in the same manner as in Example 1 except for the above.

Comparative Example 1 12 parts by weight of phthalocyanine composition (I), polyvinyl butyral resin (Sekisui Chemical Co., Ltd .: S-REC BL-)
S) 12 parts by weight, 2-ethoxyethanol 250 parts by weight and tetrahydrofuran 250 parts by weight were mixed and dispersed for 20 hours in a ball mill. A photoconductor was manufactured in the same manner as in Example 1 except for the above.

Comparative Example 2 A photoconductor was prepared in the same manner as in Comparative Example 1 except that the phthalocyanine composition (II) obtained in Production Example 2 was used instead of the phthalocyanine composition. The double charge amount of the obtained electrophotographic photosensitive member, that is, the difference between the charging potentials in the first rotation and the second rotation, and the electrostatic characteristics were measured by an electrophotographic characteristic evaluation device PDT-2000.
(Manufactured by QEA). Charging potential is about -600
The voltage applied to the charging roller is adjusted to V, and the double charge amount (ΔV0 = V01 is calculated from the charging potential V01 of the first rotation and the charging potential V02 of the second rotation at the initial stage and after 10,000 cycles.
-V02) was determined. As for electrostatic characteristics, the charging potential is about -60.
The voltage applied to the charging roller was adjusted to 0 V, the charge retention ratio DDR5 (%) after 5 seconds, the half-exposure amount E1 / 2 (mJ / m2) and the light amount 20 mJ / m2 when exposed to monochromatic light having a wavelength of 780 nm. Potential Vr after irradiation with the light
(-V) was determined. Table 1 shows the evaluation results in Examples 1 to 5 and Comparative Examples 1 and 2.

[0056]

[Table 1]

The electrophotographic photosensitive members of Examples 1 to 5 have a smaller double charge amount than the photosensitive members of Comparative Examples 1 and 2 in which the diphenoquinone derivative is not contained in the charge generation layer, and thus the double charge amount of the present invention is reduced. You have achieved your purpose.

[0058]

INDUSTRIAL APPLICABILITY The electrophotographic photoreceptor of the present invention contains the phthalocyanine composition and the diphenoquinone derivative in the charge generation layer, so that the double layer after the stress is applied at the initial stage and after 10,000 cycles without damaging the electrostatic characteristics. Since the charge is improved, an image can be formed from the first rotation without a process such as preliminary charging.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of an electrophotographic photosensitive member of the present invention.

FIG. 2 is an X-ray diffraction spectrum of CuKα of the phthalocyanine composition (I) obtained in Production Example 1.

FIG. 3 is an X-ray diffraction spectrum of CuKα of the phthalocyanine composition (II) obtained in Production Example 2.

[Explanation of symbols]

1 Conductive support 2 Undercoat layer 3 Charge generation layer 4 Charge transport layer

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Susumu Kaneko             Hitachi, Ichiba, Ibaraki Prefecture             Seikou Co., Ltd. Yamazaki Office F-term (reference) 2H068 AA14 AA19 AA21 AA34 BA12                       BA39 FA12 FA19 FA30 FB07

Claims (3)

[Claims] 1. An electrophotographic photoreceptor having a charge generation layer and a charge transport layer laminated on a conductive support, wherein the charge generation layer contains a phthalocyanine composition and a diphenoquinone derivative. 2. The phthalocyanine composition contains titanyl phthalocyanine and chloroindium phthalocyanine, and in the X-ray diffraction spectrum of CuKα, the Bragg angle (2θ ± 0.2 °) is 17.9 °, 24.0 °, and 2 °.
The electrophotographic photosensitive member according to claim 1, which has major diffraction peaks at 6.2 degrees and 27.2 degrees. 3. The phthalocyanine composition contains titanyl phthalocyanine and chloroindium phthalocyanine, and in the X-ray diffraction spectrum of CuKα, Bragg angles (2θ ± 0.2 degrees) of 7.5 degrees, 24.2 degrees and 2 degrees.
The compound having a main diffraction peak at 7.3 degrees.
Or the electrophotographic photosensitive member according to 2.