JP2657839B2 - Electrophotographic photoreceptor - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic photoreceptor, and more particularly to an electrophotographic photoreceptor used for a printer, a copying machine, etc., and particularly effective for LED light and semiconductor laser light It is about.

(Prior art)

Conventionally, electrophotographic photosensitive members having photosensitivity to visible light have been widely used in copiers, printers, and the like.

As such an electrophotographic photosensitive member, an inorganic photosensitive member provided with a photosensitive layer mainly containing an inorganic photoconductive substance such as selenium, zinc oxide, and cadmium sulfide is widely used. However, such an inorganic photoreceptor is required for an electrophotographic photoreceptor such as a copying machine or the like, and has sensitivity, heat stability, moisture resistance,
It is not always satisfactory in characteristics such as durability.

For example, selenium crystallizes due to heat, fingerprint stains when touched by hand, and the like, so that the above characteristics as an electrophotographic photosensitive member are likely to deteriorate.

Further, an electrophotographic photosensitive member using cadmium sulfide has poor humidity resistance and durability, and an electrophotographic photosensitive member using zinc oxide has a problem in durability. In addition, selenium and cadmium sulfide electrophotographic photosensitive members have great restrictions on production and handling.

In order to improve the problems of such inorganic photoconductive substances, various kinds of organic photoconductive substances have been tried to be used in the photosensitive layer of the electrophotographic photoreceptor, and research and development have been actively conducted in recent years. ing.

For example, Japanese Patent Publication No. Sho 50-10496 describes an organic photoreceptor having a photosensitive layer containing poly-N-vinylcarbazole and 2,4,7-trinitro-9-fluorenone. However, this photoreceptor is also insufficient in sensitivity and durability. Therefore, a function-separated electrophotographic photoreceptor has been developed in which the photosensitive layer is divided into two layers, the carrier generating layer and the carrier transporting layer are separately formed, and the carrier generating substance and the carrier transporting substance are respectively contained therein.

This is because the carrier generating function and the carrier transporting function can be individually assigned to different substances, and a substance exhibiting each function can be selected from a wide range. The body is relatively easy to obtain. Therefore, it is expected that an organic photoreceptor having high sensitivity and high durability can be obtained.

Numerous substances have conventionally been proposed as carrier generating substances effective for the carrier generating layer of such a function-separated type electrophotographic photoreceptor.

Examples of using an inorganic substance include, for example, Japanese Patent Publication No. 43-1619.
As described in No. 8, amorphous selenium is mentioned. The carrier generating layer containing the amorphous selenium is used in combination with the carrier transporting layer containing the organic carrier transporting substance. However, there is a problem that the carrier generation layer made of amorphous selenium is crystallized by heat or the like as described above and its characteristics are deteriorated.

Further, examples of using an organic substance as the above-mentioned carrier generating substance include an organic dye and an organic pigment.

Among these, it is known that the phthalocyanine-based compound, which is one of the organic photoconductive materials, has a longer photosensitive range than other compounds. Examples of these photoconductive phthalocyanine-based compounds include, for example,
Α-titanyl phthalocyanine described in 239248.

This α-type titanyl phthalocyanine has a Cu Kα of 1.541Å
Angle of X-ray is 7.5, 12.3 ゜, 16.3 ゜,
It has peaks at 25.3 ゜ and 28.7 ゜. However, the α-type titanyl phthalocyanine has low sensitivity, poor potential stability against repeated use, and has problems such as easy fogging in an electrophotographic process using reversal development.

[Object of the invention]

Accordingly, an object of the present invention is to provide an electrophotographic photoreceptor using titanyl phthalocyanine having good chargeability, high sensitivity, and high potential stability when used repeatedly.

[Structure of the invention and its effects]

The electrophotographic photoreceptor of the present invention uses Cu Kα characteristic X-rays (wavelength
The main peak of the Bragg angle 2θ for 1.541Å is 7.4 ゜ ± 0.2 ゜, 11.01 ± 0.2 ゜, 17.91 ± 0.2 ゜, 20.1 ゜ ± 0.2,2
An electrophotographic photoreceptor containing titanyl phthalocyanine at 6.4 ± 0.2 °, 29.0 ± 0.2 °, and particularly preferably 7.4 ° ± 0.2 °, 8.9 ° ± 0.2 °, 11.0 ° ± 0.2 having a Bragg angle of 2θ.
゜, 17.3 ゜ ± 0.2 ゜, 17.9 ゜ ± 0.2 ゜, 20.1 ゜ ± 0.2 ゜, 26.4
The photosensitive layer contains titanyl phthalocyanine having peaks at {± 0.2} and 29.0 ± 0.2.

However, the peak in the present invention is a sharp acute-angle protrusion different from noise.

The basic structure of the titanyl phthalocyanine of the present invention is represented by the following general formula.

General formula X ¹ , X ² , X ³ , and X ⁴ represent a hydrogen atom, a halogen atom, an alkyl group, or an alkoxy group, and n, m, l, and k are 0 to 4.
Represents an integer.

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

X-ray tube Cu voltage 40.0 KV current 100 mA Start angle 6.00 deg. Stop angle 35.00 deg. Step angle 0.020 deg. Measurement time 0.50 sec. Furthermore, the electrophotographic photoreceptor of the present invention containing the above titanyl phthalocyanine has an absorption spectrum At 500nm ~ 900
It is desirable that the maximum absorption wavelength in the nm region is located in the range of 620 to 860 nm, more desirably in the range of 720 to 820 nm.

The above absorption spectrum is a reflection type absorption spectrum obtained by measuring the photoreceptor prepared by the method of Example 1 described later using a “320 type self-recording spectrophotometer (manufactured by Hitachi, Ltd.)”.

Next, the method for producing titanyl phthalocyanine of the present invention will be illustratively described.

First, for example, titanium tetrachloride and phthalodinitrile
Reacting in chlornaphthalene solvent to obtain titanyl phthalocyanine (TiOPc);

Thereafter, in order to complete the reaction, an operation of hydrolysis with aqueous ammonia or the like may be inserted.

Subsequently, it is preferable to carry out treatment with a solvent such as 2-ethoxyethanol, dioxane, tetrahydrofuran, acetone, N, N-dimethylformamide, N-methylpyrrolidone, α-chloronaphthalene or the like. Next, after the TiOPc is treated by an acid paste method as described in Moser and Thomas's "phthalocyanine compound", in a solvent such as an aromatic solvent or a halogen-based solvent, at 20 ° C to 10 ° C.
Milling with stirring or mechanical shear for a time sufficient to effect crystal exchange at a temperature of 0 ° C. produces the TiOPc of the present invention. The solvent used in this case can be used by mixing with a solvent such as water, an alcohol solvent, or an ether solvent.

Typical examples of the apparatus used in the crystal transition step include a general stirring apparatus such as a homomixer, a disperser, an agitator, a stirrer, a kneader, a Banbury mixer, a ball mill, a sand mill, and an attritor.

In the present invention, other carrier generating substances may be used in addition to the above-mentioned TiOPc. The content of the other carrier-generating substance is not particularly limited, but is preferably 100 parts by weight or less, particularly preferably 50 parts by weight or less based on 100 parts by weight of TiOPc. Examples of the carrier-generating substance that can be used in combination include TiOPc having a crystal form different from that of the phthalocyanine of the present invention, specifically, TiOPc having a crystal form such as α-type, β-type, αβ-mixed type, and amorphous type. Other examples include phthalocyanine pigments, azo pigments, anthraquinone pigments, perylene pigments, polycyclic quinone pigments, and methyl squarate pigments other than those described above.

In the photoreceptor of the present invention, the carrier transporting substance used in the case of a function-separated type is not particularly limited, but typical examples thereof include oxazole derivatives, oxadiazole derivatives, thiazole derivatives, thiadiazole derivatives, triazole derivatives, and imidazole. Derivatives, imidazolone derivatives, imidazolidine derivatives, bisimidazolidine derivatives, styryl compounds, hydrazone compounds, pyrazoline derivatives, oxazolone derivatives, benzothiazole derivatives,
Benzimidazole derivatives, quinazoline derivatives, benzofuran derivatives, acridine derivatives, phenazine derivatives,
Examples include aminostilbene derivatives, poly-N-vinylcarbazole, poly-1-vinylpyrene, poly-9-vinylanthracene, and the like.

 More typically, the following compounds are mentioned.

In order to form the photosensitive layer of the photoreceptor of the present invention, a layer in which the above carrier generating substance is dispersed in a binder may be provided on a conductive support. Alternatively, the carrier generating substance and the carrier transporting substance may be combined to provide a laminated or single layer type so-called function separation type photosensitive layer.

When a function-separated type photosensitive layer is used, usually, FIGS.
As shown in the figure. That is, the layer configuration shown in FIG. 9 is obtained by forming a carrier generating layer 2 containing TiOPc according to the present invention on a conductive support 1 and laminating a carrier transporting layer 3 containing the above carrier transporting substance. FIG. 10 shows a photosensitive layer 4 'formed by inverting the carrier generating layer 2 and the carrier transporting layer 3, and FIG.
9 has an intermediate layer 5 between the photosensitive layer 4 having the layer structure shown in FIG. 9 and the conductive support 1, and FIG. 12 shows the photosensitive layer 4 'having the layer structure shown in FIG. An intermediate layer 5 is provided between the conductive support 1 and each of the intermediate supports 5 to prevent injection of free electrons into the conductive support 1. The layer configuration shown in FIG. A photosensitive layer 4 "containing a substance 6 and a carrier transporting substance 7 combined therewith is formed, and the layer structure shown in FIG. 14 is formed between the photosensitive layer 4" and the conductive support 1. This is provided with an intermediate layer 5.

The carrier generating layer 2 and the carrier transporting layer 3 in the case of forming a two-layered photosensitive layer can be provided by the following method.

(A) A method in which a carrier-generating substance and a carrier-transporting substance are each dissolved in an appropriate solvent, or a solution in which a binder is added thereto and mixed and dissolved is applied.

(B) A method in which a carrier-generating substance and a carrier-transporting substance are each made into fine particles in a dispersion medium by a ball mill, a homomixer, ultrasonic waves or the like, and a binder is added, if necessary, and then mixed and dispersed to apply a dispersion.

Solvents or dispersion media used for forming the carrier generation layer and the carrier transport layer include butylamine, N, N-dimethylformamide, acetone, methyl ethyl ketone, cyclohexanone, benzene, toluene, xylene, chloroform, 1,2-dichloroethane, Examples thereof include dichloromethane, tetrahydrofuran, dioxane, methanol, ethanol, isopropanol, ethyl acetate, butyl acetate, and dimethyl sulfoxide. When a binder is used for forming the carrier generation layer or the carrier transport layer, any binder can be used, but in particular, a polymer that is hydrophobic and has a high dielectric constant and an electrical insulating film-forming ability. Polymers are preferred. Examples of such polymers include, but are not limited to, the following.

1) Polycarbonate 2) Polyester 3) Methacrylic resin 4) Acrylic resin 5) Polyvinyl chloride 6) Polyvinylidene chloride 7) Polystyrene 8) Polyvinyl acetate 9) Styrene-butadiene copolymer 10) Vinylidene chloride-acrylonitrile copolymer 11) Vinyl chloride-vinyl acetate copolymer 12) vinyl chloride-vinyl acetate-maleic anhydride copolymer 13) silicone resin 14) silicone-alkyd resin 15) phenol-formaldehyde resin 16) styrene-acrylic copolymer resin 17) styrene- Alkyd resin 18) Poly-N-vinyl carbazole 19) Polyvinyl butyral 20) Polycarbonate Z resin These binders can be used alone or as a mixture of two or more. The ratio of the carrier generating substance to the binder 100 is 10 to 600 wt / wt, preferably 50 to 40 wt / wt.
0 wt / wt and the carrier transporting material is preferably 10 to 500 wt / wt.

The thickness of the carrier generation layer 2 thus formed is
It is preferably 0.01 to 20 μm, more preferably
0.05 to 5 μm. The thickness of the carrier transport layer is 2 to 100
μm, preferably 5 to 30 μm.

When the photosensitive layer is formed by dispersing the carrier generating substance, the carrier generating 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, and in some cases, discharge occurs at the protruding portion of the particles, or The toner film adheres easily to cause toner filming phenomenon.

Further, the photosensitive layer may contain one or more electron accepting substances for the purpose of improving sensitivity, reducing residual potential or reducing fatigue when used repeatedly. Examples of the electron-accepting substance that can be used here include succinic anhydride, maleic anhydride, dibromosuccinic anhydride, phthalic anhydride, tetrachlorophthalic anhydride, tetrabromophthalic anhydride, 3-nitrophthalic anhydride, and 4-nitrophthalic anhydride. Nitro phthalic anhydride, pyromellitic anhydride, melitic anhydride, tetracyanoethylene, tetracyanoquinodimethane, o-dinitrobenzene, m-dinitrobenzene, 1,3,5-trinitrobenzene, paranitrobenzonitrile, picryl Chloride, quinone chlorimide, chloranil, bulmanil, dichlorodicyanoparabenzoquinone, anthraquinone, dinitroanthraquinone, 9-fluorenylidene [dicyanomethylenemalonodinitrile], polynitro-
9-fluorenylidene- [dicyanomethylenemalonodinitrile], picric acid, o-nitrobenzoic acid, p-nitrobenzoic acid, 3,5-dinitrobenzoic acid, pentafluorobenzoic acid, 5-nitrosalicylic acid, 3,5-dinitro Examples thereof include salicylic acid, phthalic acid, melitic acid, and other compounds having a high electron affinity.

Further, the addition ratio of the electron-accepting substance is such that the carrier-generating substance: electron-accepting substance is 100: 0.01 to 200, preferably 1 by weight.
00: 0.1 to 100.

The photosensitive layer may contain a deterioration inhibitor such as an antioxidant or a light stabilizer for the purpose of improving storage stability, durability, and dependence on the band environment. Compounds used for such purposes include, for example, chromanol derivatives such as tocopherol and etherified or esterified compounds thereof, polyarylalkane compounds, hydroquinone derivatives and mono- and dietherified compounds thereof, benzophenone derivatives, benzotriazole derivatives, thioethers Compounds, phosphonates, phosphites,
A phenylenediamine derivative, a phenol compound, a hindered phenol compound, a linear amine compound, a cyclic amine compound, a hindered amine compound, and the like are effective.
Specific examples of particularly effective compounds include “IRGANOX101
0 "," IRGANOX565 "manufactured by Ciba-Gaiky)" Sumilyzer BHT "," Sumilyzer MDP "(manufactured by Sumitomo Chemical Co., Ltd.)
Hindered phenol compounds such as "Sanol LS-262"
And "Sanol LS622LD" (manufactured by Sankyo).

As the binder used for the intermediate layer, the protective layer, and the like, those described above for the carrier generation layer and the carrier transport layer can be used.Other polyamide resins, nylon resins, ethylene-vinyl acetate copolymers, Polyvinyl alcohol, cellulose derivatives and the like are effective.

The support 1 on which the above-mentioned photosensitive layer is to be provided is coated, vapor-deposited with a metal plate, a metal drum or a conductive polymer, a conductive compound such as indium oxide or a conductive thin layer made of a metal such as aluminum, palladium or gold. What is provided on a substrate such as paper or a plastic film by means such as lamination is used.

As the intermediate layer functioning as an adhesive layer or a barrier layer, a layer composed of an organic polymer substance such as a polymer described above as the binder resin, polyvinyl alcohol, ethyl cellulose, carboxymethyl cellulose, or aluminum oxide is used. Can be

According to the present invention, as described above, by using the above-mentioned TiOPc, it is possible to obtain an electrophotosensitive member particularly effective for LED light and semiconductor laser light.

Further, the electrophotographic photoreceptor of the present invention has a feature of being excellent in sensitivity, charging ability and potential stability.

〔Example〕

(Synthesis Example 1) 18 g of titanium tetrachloride was added dropwise to a mixture of 40 g of phthalodinitrile and 500 ml of α-chloronaphthalene under a nitrogen stream, and the temperature was gradually raised to a temperature in the range of 200 ° C to 230 ° C for 3 hours. The reaction was completed by stirring. Thereafter, the mixture was allowed to cool to room temperature and filtered to obtain dichlorotitanium phthalocyanine (TiCl ₂ Pc) as a product.

The obtained dichlorotitanium phthalocyanine was hydrolyzed with 300 ml of concentrated aqueous ammonia, and then washed with acetone and o-dichlorobenzene.

Next, 5 g of the obtained TiOPc was heated at a temperature of 3 to 5 ° C. in 96% sulfuric acid 100.
After stirring for 2 hours in g, filtration was performed. The obtained sulfuric acid solution was dropped into water 3, and the precipitated crystals were collected by filtration. The crystals were repeatedly washed with deionized water until the filtrate became neutral, and dried sufficiently.

Further, sulfuric acid-treated TiOPc 2 g is ethylene glycol 120 cc.
After stirring at a temperature of 180 ° C to 190 ° C for 3 hours, the mixture was filtered and thoroughly washed with methanol. The crystal thus obtained had a Bragg angle 2θ of 7.4 °, 11.0 as shown in FIG.
It was found that the TiOPc of the present invention had peaks at ゜, 17.9 ゜, 20.1 ゜, 26.4 ゜, and 29.0 ゜.

(Synthesis Example 2) 2 g of TiOPc treated with sulfuric acid in Synthesis Example 1 was stirred in 120 cc of 2-butoxyethanol at a temperature of 160 ° C for 3 hours, then filtered, and sufficiently washed with methanol. The crystal thus obtained has a Bragg angle of 2 as shown in FIG.
θ was found to be TiOPc of the present invention having peaks at 7.4 °, 11.0 °, 17.9 °, 20.1 °, 26.4 °, and 29.0 °.

(Synthesis Example 3) As a dispersion medium, 35 g of ethylene glycol and 35 g of o-dichlorobenzene were added to 2.5 g of TiOPc treated with sulfuric acid in Synthesis Example 1, and milling was performed in a temperature range of 40 ° C to 80 ° C with a sand grinder. Subsequently, the dispersion medium was removed, and washing was performed with acetone and methanol. The resulting crystal is the third
As shown in the figure, the Bragg angle 2θ 7.4 °, 11.0 °, 17.9 °,
20.1 ゜, 26.0 ゜, TiOPc of the present invention having a peak at 29.0 ゜
It turned out to be.

(Comparative Synthesis Example) 2 g of TiOPc treated with sulfuric acid in Synthesis Example 1 was heated and refluxed in 120 ml of 2-methoxyethanol for 3 hours, and then filtered and sufficiently washed with methanol. The crystal thus obtained had a Bragg angle of 2θ of 7.7 as shown in FIG.
Α with peaks at 5 ゜, 12.4 ゜, 16.3 ゜, 25.3 ゜, 28.6 ゜
It was found to be type TiOPc.

Example 1 Ti having the X-ray diffraction pattern of FIG. 1 obtained in Synthesis Example 1
3 parts (wt) of OPc, 20 parts of a silicone resin (“KR-5240, 15% xylene butanol solution” manufactured by Shin-Etsu Chemical Co., Ltd.) and 100 parts (wt) of methyl ethyl ketone were pulverized and dispersed by a sand grinder to obtain a dispersion. The resulting dispersion is applied to an aluminum plate by a dip (dipping) coating method, and a film thickness of about 0.2 μm
Was formed.

On the other hand, 1 part of the carrier transporting substance (1), 2 parts (wt) of a polycarbonate resin ("Iupilon Z200" manufactured by Mitsubishi Gas Chemical Company) and silicone oil ("KF-54" manufactured by Shin-Etsu Chemical Co., Ltd.) were mixed with 1,2-dichloroethane 15 (Wt), and applied on the carrier generating layer by dipping.
The carrier was dried at 0 ° C. for 30 minutes to form a carrier transporting layer having a thickness of 18 μm, thereby preparing a photoreceptor. This photoconductor is referred to as Sample 1. FIG. 5 shows the absorption spectrum of this photoreceptor.

(Example 2) Synthesis example 2 in place of TIOPC of synthesis example 1 in example 1
A photoconductor was prepared in the same manner as in Example 1, except that the TiOPc shown in FIG. 2 was used. This is designated as Sample 2. FIG. 6 shows the absorption spectrum of this photoreceptor.

(Example 3) Synthesis example 3 in place of TIOPC of synthesis example 1 in example 1
A photoconductor was prepared in the same manner as in Example 1, except that the TiOPc shown in FIG. 3 was used. This is designated as Sample 3. FIG. 7 shows the absorption spectrum of this photoreceptor.

Comparative Example 1 A photoconductor was prepared in the same manner as in Example 1, except that the α-TiOPc of FIG. 4 obtained in Comparative Synthesis Example 1 was used instead of the TiOPc of Synthesis Example 1 in Example 1. . This is designated as Comparative Sample (1).

 FIG. 8 shows the absorption spectrum of this photoreceptor.

(Evaluation) Each sample obtained above was evaluated as follows. Using a paper analyzer EPA-8100 (manufactured by Kawaguchi Electric Co., Ltd.), the surface was charged for 5 seconds under a discharge condition of -80 μA, and the surface potential immediately after the charging [Va], the surface potential after being left in the dark for 5 seconds [Vi], and the surface illuminance were Exposure to 2 (lux)
Exposure [E 1/2] (lux · s) until surface potential becomes 1 / 2Vi
ec) The dark decay rate [D] was determined from the following equation.

 Table 1 shows these results.

From this result, it can be seen that the TiOPc of the present invention has particularly high sensitivity and good chargeability.

On the other hand, the α-type TiOPc of Comparative Sample (1) has low sensitivity, large dark decay rate, and is inferior in chargeability to the electrophotographic photoreceptor of the present invention.

Next, a normal Carlson process was carried out using these photoreceptors, and a difference [ΔVb] between the initial surface and the surface potential immediately after charging 10,000 times [ΔVb] and a residual potential [Vr] after 10,000 times were obtained.

In addition, the initial value and the value after 10,000 times of the surface potential [Vw] after irradiation with a constant amount of light were determined.

 Table 2 shows these results.

From these results, it can be seen that the electrophotographic photoreceptor of the present invention has excellent potential stability during repeated use.

From the above, the electrophotographic photoreceptor of the present invention has high sensitivity, good chargeability, and excellent potential stability during repeated use.

(Example 4) A solution prepared by dissolving 1 part of a carrier transporting substance (1) and 1.5 parts of a polyester resin "Vylon 200" (manufactured by Toyobo Co., Ltd.) in 15 parts of 1,2-dichloroethane was applied on an aluminum drum by dip coating. After coating and drying, a carrier transport layer having a thickness of 15 μm was formed.

On the other hand, 1 part of TioPC of Synthesis Example 3 of the present invention, 3 parts of polycarbonate "Panlite L-1250" (manufactured by Teijin Chemicals Ltd.) as a binder resin, 15 parts of monochlorobenzene as a dispersion medium, and 35 parts of 1,2-dichloroethane were used in a ball mill. Then, the carrier transporting substance (1) was further added so as to be 75 wt% with respect to the binder resin. The dispersion thus obtained was applied onto the carrier transporting layer by a spray coating method to form a carrier generating layer having a thickness of 5 μm.

The photoreceptor thus obtained was evaluated in the same manner as in Evaluation 1, except that the charging polarity was set to a positive polarity.

Va = 1400 (V) Vi = 1120 (V) D = 20.0 (%) E 1/2 = 1.37 (lux · sec) (Example 5) On an aluminum drum, vinyl chloride-vinyl acetate-
An intermediate layer having a thickness of 0.1 μm and comprising a maleic anhydride copolymer “S-LEC MF-10” (manufactured by Sekisui Chemical Co., Ltd.) was formed.

On the other hand, 1 part of TiOPc of Synthesis Example 3 of the present invention was ball-milled, and then polycarbonate resin “PANLITE L-125”.
0 ", 3 parts of monochlorobenzene, and 35 parts of 1,2-dichloroethane were added and dispersed.

To the obtained dispersion, 2 parts of the carrier transporting substance (1) was further added, and the mixture was applied on the intermediate layer by a spray coating method and dried to form a photosensitive layer having a thickness of 20 μm.

The photoreceptor thus obtained was evaluated in the same manner as in Evaluation 1, except that the charging polarity was set to a positive polarity.

Va = 1375 (V) Vi = 1095 (V) D = 20.4 (%) E1 / 2 = 1.59 (lux · sec)

[Brief description of the drawings]

FIGS. 1 and 5 show X of TiOPc used in Example 1, respectively.
Line diffraction diagram and absorption spectrum of the photoreceptor. FIGS. 2 and 6 show X of TiOPc used in Example 2, respectively.
Line diffraction diagram and absorption spectrum of the photoreceptor. FIGS. 3 and 7 show X of TiOPc used in Example 3, respectively.
Line diffraction diagram and absorption spectrum of the photoreceptor. 4 and 8 show the α-type TiOPc used in Comparative Example 1, respectively.
FIG. 1 shows an X-ray diffraction pattern and an absorption spectrum of the photosensitive member. 9 to 14 are cross-sectional views showing specific examples of the layer constitution of the electrophotographic photosensitive member of the present invention. DESCRIPTION OF SYMBOLS 1 ... Conductive support 2 ... Carrier generation layer 3 ... Carrier transport layer 4, 4 ', 4 "... Photosensitive layer 5 ... Intermediate layer

 ──────────────────────────────────────────────────続 き Continuation of front page (72) Inventor Kiyoshi Sawada 1 Sakuracho, Hino-shi, Tokyo Examiner in Konica Corporation Toshihiko Nakazawa (56) References JP-A-1-1533757 (JP, A) JP-A Sho 62-67094 (JP, A) JP-A-1-207755 (JP, A) JP-A-62-272272 (JP, A) JP-A-63-210942 (JP, A) JP-A-63-116158 (JP, A) A)

Claims (1)

(57) [Claims] At least 7.4 K ± 0.2 ゜, 11.0 ゜ ± 0.2 ゜, 17.9 ゜ ± 0.2 ゜, 20.1 ゜ ± 0.2 ゜, 26.4 ゜ ± of Bragg angle 2θ with respect to characteristic X-ray (wavelength 1.541 °) of Cu Kα. 0.2 ゜,
An electrophotographic photoreceptor containing a crystalline form of titanyl phthalocyanine giving a main peak at 29.0 ° ± 0.2 °.