JPH08283598A - Indium phthalocyanine bromide and electrophotographic photoreceptor - Google Patents

Abstract

PURPOSE: To obtain an electrophotographic photosensitive material high in sensitivity and excellent in electrical property stability repeated use, by using indiumphthalocyanine bromide having diffraction peaks at specified Bragg's angles in the X-ray diffraction diagram. CONSTITUTION: Indium tribromide and 1,3-diiminoisoindoline in a mole ratio of 1:2 to 1:6 are dissolved in 1,3-dimethyl-2-imidazolidinone so that 1 pt.wt. 1,3-diiminoisoindoline is present for 1 pt.wt. or more 1,3-dimethyl-2- imidazolidinone and the indium tribromide and the 1,3-diiminoisoindoline are reacted at 80 to 300 deg.C for 10min to 30 hours to obtain the indiumphthalocyanine bromide as a charge generating material having diffraction peaks at Bragge's angles (2θ+0.2 degree) of 9.1, 9.7, 16.5, and 27.2 degrees in the X-ray diffraction diagram. A binder and a solvent are added to and mixed with the charge generating material to disperse it and the resulting mixture is applied on a conductive support and is dried to form a charge generating layer. The charge generating layer is coated with a mixed paint of a charge carrying material, a binder, and a solvent to form a charge carrying layer to produce the electrophotographic photosensitive material.

Description

Detailed Description of the Invention

[0001]

The present invention has a novel crystal form,
The present invention relates to indium phthalocyanine bromide useful as a photoconductive material and an electrophotographic photoreceptor containing the compound in a photoconductive layer.

[0002]

2. Description of the Related Art In recent years, electrophotographic printers and copying machines using a semiconductor laser as a light source have been actively developed. As an electrophotographic photosensitive member to be mounted on these, one using a phthalocyanine pigment having high absorption efficiency for light around 800 nm which is an oscillation region of a semiconductor laser in a photoconductive layer is known.

It is known that the phthalocyanine pigments used in these electrophotographic photoreceptors have different crystal types depending on the manufacturing method, processing method, etc., and the electrophotographic characteristics such as sensitivity differ depending on the crystal type. .

Of the phthalocyanine pigments, indium phthalocyanine has been extensively studied because it exhibits high electrophotographic characteristics with respect to light around 800 nm, which is the oscillation wavelength region of a semiconductor laser.

JP-A-59-155851 discloses β-phase indium phthalocyanine as a pigment having high sensitivity in the near infrared region. However, the indium phthalocyanine pigment disclosed in this publication has a problem that it is preferable to purify the pigment by sublimation in order to obtain a high dark potential holding ratio and high sensitivity, and its productivity is low. Further, in JP-A-59-174847, a vapor-deposited film of indium phthalocyanine bromide is exposed to a vapor of tetrahydrofuran on a conductive support, and an absorption maximum peak of an electronic spectrum is 800 nm which is a semiconductor laser oscillation wavelength region. A function-separated type electrophotographic photosensitive member is disclosed in which a charge generation layer and a charge transport layer, which are formed by shifting a film in the front-rear direction, are sequentially laminated. However, the technique disclosed in this publication is to form an electric charge generating layer by vapor deposition of indium phthalocyanine bromide and then exposing it to a solvent vapor, but the vapor deposition method requires a large amount of equipment investment as compared with the coating method. In addition, there is a problem in that it cannot be mass-produced inexpensively because it is inferior in mass productivity.

In order to solve such a problem, Japanese Patent Application Laid-Open No. 61-124951 discloses that the Bragg angle (2θ ± 0.2 °) in the X-ray diffraction spectrum of CuKα is
Disclosed is an electrophotographic photoreceptor comprising a photoconductive layer containing a brominated indium phthalocyanine having diffraction peaks at 6.0 degrees, 12.4 degrees, 25.4 degrees and 27.8 degrees provided on a conductive support. In Japanese Patent Laid-Open No. 63-27562, the Bragg angle (2θ ± 0.2 °) in the X-ray diffraction spectrum of CuKα is 7.4 °, 16.7 °, 25.
An electrophotographic photosensitive member is disclosed in which a photoconductive layer containing brominated indium phthalocyanine having diffraction peaks at 3 degrees, 27.5 degrees and 28.4 degrees is provided on a conductive support, and JP-A-5-98179 discloses. In the publication, the Bragg angle (2θ ± 0.2 degrees) in the X-ray diffraction spectrum of CuKα is disclosed.
, 7.0 degrees, 9.4 degrees, 14.0 degrees, 15.4 degrees, 1
8.0 degrees, 19.4 degrees, 23.8 degrees, 26.1 degrees, 2
An electrophotographic photosensitive member is disclosed in which a photoconductive layer containing brominated indium phthalocyanine having diffraction peaks at 7.9 degrees and 30.2 degrees is provided on a conductive support, and JP-A-5-98180 discloses it. Has a Bragg angle (2θ ± 0.2 degrees) of 6.7 in the X-ray diffraction spectrum of CuKα.
Degree, 7.4 degrees, 13.5 degrees, 14.9 degrees, 15.9 degrees,
An electrophotographic photosensitive member is disclosed in which a photoconductive layer containing brominated indium phthalocyanine having diffraction peaks at 24.8 degrees and 26.2 degrees is provided on a conductive support.

[0007]

However, even with these techniques, the high sensitivity in the semiconductor laser oscillation region and the stability during repeated use are still not sufficiently satisfactory, and further development is desired. ing.

The problem to be solved by the present invention is to provide a novel crystal type having high sensitivity in the semiconductor laser oscillation region and stability during repeated use by using it in the photoconductive layer of an electrophotographic photoreceptor. Providing indium phthalocyanine bromide.

[0009]

Means for Solving the Problems The inventors of the present invention have made extensive studies to solve the above problems, and as a result, have completed the present invention.

That is, according to the present invention, in order to solve the above problems, in the X-ray diffraction diagram, the Bragg angle (2θ ± 0.2
Indium phthalocyanine bromide having diffraction peaks at 9.1 degrees, 9.7 degrees, 16.5 degrees, and 27.2 degrees.

In order to solve the above-mentioned problems, the present invention has a Bragg angle (2θ ± 0.2 °) of 9.1 °, 9.7 ° on an X-ray diffraction pattern on a conductive support. 16.5
And a photoconductive layer containing indium phthalocyanine bromide having a diffraction peak at 27.2 degrees.

The present invention will be described in detail below.

The Bragg angle (2θ ± 0.2 degrees) in the X-ray diffraction pattern of the present invention is the Cu-Kα ray (wavelength 1.541).
Ångström).

The indium bromide phthalocyanine of the present invention is produced by heating indium tribromide and 1,3-diiminoisoindoline in a solvent containing 1,3-dimethyl-2-imidazolidinone. can do. The molar ratio of indium tribromide and 1,3-diiminoisoindoline is preferably 1: 2 to 1: 6, and particularly preferably 1: 4. The 1,3-dimethyl-2-imidazolidinone used as a solvent in the reaction is 1 part by weight or more, preferably 3 parts by weight or more, based on 1 part by weight of 1,3-diiminoisoindoline, also from the economical aspect. It is preferably used in the range of 3 to 50 parts by weight.

When synthesizing indium phthalocyanine bromide, it is possible to use a solvent other than 1,3-dimethyl-2-imidazolidinone as a solvent. As such a solvent, for example, quinoline, tri-n-butylamine, N-methylpyrrolidone, N, N-dimethylformamide, dimethylsulfoxide, tetralin, α-chloronaphthalene, etc. which have been conventionally used for the synthesis of phthalocyanines are used. Known materials can be used.

Although the temperature and time during the reaction can be arbitrarily set, increasing the reaction temperature more than necessary and prolonging the reaction time will cause the characteristics of the reaction product due to the decomposition of the chemical species in the reaction system. The reaction temperature is preferably in the range of 80 ° C. to 300 ° C. and the reaction time is preferably in the range of 10 minutes to 30 hours because of the risk of lowering.

The electrophotographic photosensitive member of the present invention has a Bragg angle (2θ ± 0.2 in an X-ray diffraction pattern on a conductive support.
The photoconductive layer containing indium phthalocyanine bromide having a diffraction peak at 9.1 degrees, 9.7 degrees, 16.5 degrees, and 27.2 degrees is provided. The structure can be adopted. Examples thereof are shown in FIGS. 1 to 3.

The electrophotographic photosensitive member of FIGS. 1 and 2 has a charge generating layer 2 composed mainly of a charge generating material on a conductive support 1.
And a photoconductive layer 4a or 4b consisting of a charge transporting material and a charge transporting layer 3 made of a binder resin as necessary for forming the charge transporting layer. The electrophotographic photosensitive member shown in FIG. 3 has a photoconductive layer 4c in which a charge generating material 5 is dispersed in a charge transfer medium 6 provided on a conductive support 1.

In the case of the electrophotographic photoreceptors of FIGS. 1 and 2, the charge generating material contained in the charge generating layer 2 generates charges, while the charge transporting layer 3 receives the injection of charges and transports the charges. To do. That is, the charges required for light attenuation are generated in the charge generating material, and the charges are transported in the charge transport medium. In the electrophotographic photosensitive member of FIG. 3, the charge generating material generates charges with respect to light, and the charges are transferred by the charge transfer medium.

In the electrophotographic photoreceptor of FIG. 1, fine particles of the charge generating material are dispersed in a solvent in which a binder resin is dissolved, if necessary, and the resulting dispersion is applied and dried, and then the charge transporting material is applied. Can be prepared by coating a solution obtained by dissolving the above alone or, if necessary, together with a binder resin and dissolving it, followed by drying.

In the electrophotographic photosensitive member of FIG. 2, a solution in which a charge transport material is used alone or, if necessary, a binder resin is used in combination is applied on a conductive support and dried, and then the charge generating material is applied. It can be manufactured by coating and drying a dispersion liquid obtained by dispersing the fine particles of (1) in a solvent or a binder resin solution.

In the electrophotographic photoreceptor of FIG. 3, fine particles of the charge generating material are dispersed in a solution in which the charge transporting material is used alone or, if necessary, a binder resin is also used in combination, and the resulting solution is dispersed on a conductive support. It can be manufactured by coating and drying.

In the case of the electrophotographic photoconductors shown in FIGS. 1 and 2, the photoconductive layer has a thickness of 5 μm or less.
The thickness is preferably 0.01 to 2 μm, and the thickness of the charge transport layer is 3 to 50 μm, preferably 5 to 30 μm. FIG.
In the case of the electrophotographic photosensitive member of, the thickness of the photoconductive layer is 3 to
The thickness is 50 μm, preferably 5 to 30 μm.

The proportion of the charge transport material in the charge transport layer in the electrophotographic photoreceptor of FIGS. 1 and 2 is 5 to 100% by weight.
Can be appropriately selected within the range of, preferably 40 to 80% by weight. The ratio of the charge generation material in the charge generation layer of the electrophotographic photosensitive member of FIGS.
It can be selected appropriately in the range of 100% by weight, and preferably in the range of 40 to 80% by weight. In the electrophotographic photoreceptor of FIG. 3, the proportion of the charge transport material in the photoconductive layer can be appropriately selected within the range of 5 to 99% by weight, and the proportion of the charge generating material is preferably 1 to 50% by weight. Is 3 to 20% by weight. It should be noted that a plasticizer and a sensitizer can be used together with the binder resin in the production of any of the electrophotographic photoreceptors shown in FIGS.

The conductive support used in the electrophotographic photosensitive member of the present invention includes, for example, aluminum, copper, zinc,
Stainless steel, chrome, titanium, nickel, molybdenum,
Metals or alloys such as vanadium, indium, gold and platinum,
Alternatively, a conductive polymer, a conductive compound such as indium oxide; a paper, a plastic film, a ceramic, or the like, which is coated, vapor-deposited or laminated with a metal or alloy such as aluminum, palladium, or gold, and the like, may be a conductive support. The body surface may be subjected to chemical or physical treatment.

The electrophotographic photosensitive member of the present invention may have various shapes such as a drum shape, a flat plate shape, a sheet shape and a belt shape, although it depends on the support used.

In the electrophotographic photosensitive member of the present invention, the Bragg angle (2θ ± 2
0.2 degrees) is 9.1 degrees, 9.7 degrees, 16.5 degrees, 2
If necessary, a known charge generating material can be used in combination with the indium phthalocyanine bromide of the present invention having a diffraction peak at 7.2 degrees.

Examples of the charge generating material which can be used in combination with the indium phthalocyanine bromide of the present invention include:
Azo pigments such as monoazo pigments, disazo pigments and trisazo pigments; phthalocyanine pigments such as various metal phthalocyanines, metal-free phthalocyanines and naphthalocyanines; condensed polycyclic pigments such as perinone pigments, perylene pigments, anthraquinone pigments, quinacridone pigments; squares There can be mentioned, for example, lithium dyes, azurenium dyes, thiapyrylium dyes, cyanine dyes and the like. The charge generating materials used in combination are not limited to those described here, and in use thereof, in addition to the indium phthalocyanine bromide of the present invention, used alone or in combination of two or more kinds. be able to.

The charge transport material used in the electrophotographic photoreceptor of the present invention can be broadly classified into low molecular weight compounds and high molecular weight compounds.

Examples of the charge transporting material of the low molecular weight compound include pyrene; carbazoles such as N-ethylcarbazole, N-isopropylcarbazole and N-phenylcarbazole; N-methyl-N-phenylhydrazino-3.
-Methylidene-9-ethylcarbazole, N, N-diphenylhydrazino-3-methylidene-9-ethylcarbazole, p- (N, N-dimethylamino) benzaldehyde diphenylhydrazone, p- (N, N-diethylamino) benzaldehyde diphenyl Hydrazone, p-
(N, N-diphenylamino) benzaldehyde diphenylhydrazone, 1- [4- (N, N-diphenylamino) benzylideneimino] -2,3-dimethylindoline, N-ethylcarbazole-3-methylidene-N-aminoindoline, Hydrazones such as N-ethylcarbazole-3-methylidene-N-aminotetrahydroquinoline; 2,5-bis (p-diethylaminophenyl)-
Oxadiazoles such as 1,3,4-oxadiazole; 1-phenyl-3- (p-diethylaminostyryl) -5- (p-diethylaminophenyl) pyrazoline, 1- [quinolyl- (2)]-3 Pyrazolines such as-(p-diethylaminophenyl) pyrazolin; tri-p
-Tolylamine, N, N'-diphenyl-N, N'-bis (3-methylphenyl) -1,1'-biphenyl-
Aryl amines such as 4,4′-diamine; butadienes such as 1,1-bis (p-diethylaminophenyl) -4,4-diphenyl-1,3-butadiene; 4- (2,
2-diphenylethenyl) -N, N-diphenylbenzenamine, 4- (1,2,2-triphenylethenyl)
Examples thereof include styryls such as -N, N-diphenylbenzenamine.

Examples of the charge transport material of the polymer compound include poly-N-vinylcarbazole, halogenated poly-N-vinylcarbazole, polyvinylpyrene,
Examples thereof include polyvinyl anthracene, polyvinyl acridine, poly-9-vinylphenyl anthracene, pyrene-formamide resin, ethylcarbazole-formaldehyde resin, triphenylmethane polymer, and polyphenylalkylsilane.

The charge transport material is not limited to those described here, and may be used alone or in combination of two or more when used.

As the binder resin which can be used if necessary, it is preferable to use a hydrophobic and electrically insulating polymer compound capable of forming a film. Examples of such high molecular weight polymers include polycarbonate, polyester, methacrylic resin, acrylic resin, polyvinyl chloride,
Polyvinylidene chloride, polystyrene, polyvinyl acetate, polyvinyl butyral, styrene-butadiene copolymer, vinyl chloride-vinyl acetate-maleic anhydride copolymer, silicone resin, silicone-alkyd resin, phenol-formaldehyde resin, styrene-alkyd resin, Examples thereof include poly-N-vinylcarbazole, polyvinyl formal, and polysulfone.

The binder resin is not limited to those described here, and may be used alone or in combination with the binder resin.
It can also be used as a mixture of two or more species.

Further, the electrophotographic photosensitive member has film-forming properties, flexibility,
In order to improve mechanical strength, well-known additives such as a plasticizer and a surface modifier may be used together with these binder resins.

Examples of the plasticizer include biphenyl, biphenyl chloride, o-terphenyl, p-terphenyl,
Dibutyl phthalate, diethyl glycol phthalate,
Examples thereof include dioctyl phthalate, triphenyl phosphoric acid, methylnaphthalene, benzophenone, chlorinated paraffin, polypropylene, polystyrene and various fluorohydrocarbons.

Examples of the surface modifier include silicone oil and fluorine resin.

Any known sensitizer can be used as the sensitizer which is optionally used in the photoconductive layer.

Examples of the sensitizer include chloranil, tetracyanoethylene, methyl violet, rhodamine B, cyanine dye, merocyanine dye, pyrylium dye and thiapyrylium dye.

In the electrophotographic photosensitive member of the present invention, in order to improve storage stability, durability and environmental resistance, the photoconductive layer contains a deterioration inhibitor such as an antioxidant or a light stabilizer. You can also let it. Examples thereof include phenol compounds, hydroquinone compounds, amine compounds and the like.

Further, in the present invention, in order to improve the adhesion between the electroconductive support and the photoconductive layer and prevent the injection of free charges from the electroconductive support to the photoconductive layer, the electroconductive support is provided. If necessary, an adhesive layer or a barrier layer may be provided between the photoconductive layer and the photoconductive layer.

Materials used for these layers include polymer compounds used for the binder resin, casein, gelatin, ethyl cellulose, nitrocellulose,
Carboxy-methyl cellulose, vinylidene chloride-based polymer latex, styrene-butadiene-based polymer latex, polyvinyl alcohol, polyamide, polyurethane, phenol resin, aluminum oxide, tin oxide,
Titanium oxide and the like are mentioned, and the film thickness is preferably 5 μm or less.

When the laminated electrophotographic photosensitive member is formed by coating, the solvent that dissolves the binder resin varies depending on the type of the binder resin, but it is desirable to select from those that do not dissolve the lower layer. Specific examples of the organic solvent include alcohols such as methanol, ethanol and n-propanol; acetone, methyl ethyl ketone,
Ketones such as cyclohexanone; amides such as N, N-dimethylformamide, N, N-dimethylacetamide; ethers such as tetrahydrofuran, dioxane, methylcellosolve; esters such as methyl acetate, ethyl acetate; dimethyl sulfoxide, sulfolane, etc. Sulfoxides and sulfones; dichloromethane, chloroform,
Aliphatic halogenated hydrocarbons such as carbon tetrachloride and trichloroethane; aromatics such as benzene, toluene, xylene, monochlorobenzene, and dichlorobenzene.

Examples of the coating method include dip coating method, spray coating method, spinner coating method, bead coating method, wire bar coating method, blade coating method, roller coating method and curtain coating method. In order to obtain a more uniform coating thickness, it is desirable to use the dip coating method.

The indium phthalocyanine bromide of the present invention has high sensitivity in the semiconductor laser oscillation region and excellent stability during repeated use, and the electrophotographic photoreceptor containing this compound in the photoconductive layer has the above constitution. Therefore, as is clear from the examples described below, the electrophotographic photosensitive member is excellent in high sensitivity and electric property stability during repeated use.

[0046]

EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to the examples. In the examples, "part" means "part by weight".

<Example 1> [Production of indium phthalocyanine bromide] In a reactor, 1,3-diiminoisoindoline 25.2
Part, indium tribromide 15.3 parts, 1,3-dimethyl-
150 parts of 2-imidazolidinone was taken, heated to 200 ° C. under stirring in a nitrogen atmosphere, and then reacted at the same temperature for 6 hours. The reaction mixture was cooled to 100 ° C. and then filtered while hot to recover a crude reaction product. The crude reaction product obtained was added to 100 parts of methanol and stirred at room temperature for 30 minutes.
It was stirred for minutes and filtered. This washing operation with methanol was performed twice, and then the same washing operation was performed twice with 100 parts of acetone, and after vacuum drying at 50 ° C., 10.8 parts by weight of indium phthalocyanine bromide was obtained.

An X-ray powder diffraction pattern of the obtained indium phthalocyanine bromide measured by an X-ray diffractometer RAD-B system manufactured by Rigaku Denki Co., Ltd. is shown in FIG. 4, and an infrared spectrophotometer IR manufactured by JASCO Corporation The infrared absorption spectrum (KBr tablet method) measured at −810 is shown in FIG.

Example 2 The indium phthalocyanine bromide obtained in Example 1 was dry-ground for 10 hours using a planetary mill containing agate balls. FIG. 6 shows a powder X-ray diffraction pattern of fine powder of dry-ground indium phthalocyanine bromide measured by an X-ray diffractometer RAD-B system manufactured by Rigaku Denki Co., Ltd.

<Example 3> 2 parts of indium phthalocyanine bromide obtained in Example 2 and 1 part of butyral resin (trade name "ESREC BH-3" manufactured by Sekisui Chemical Co., Ltd.), 52 parts of dichloromethane and 1, 1,2-trichloroethane 7
The mixture was added to 8 parts of the mixed solvent and dispersed and mixed using a paint shaker to obtain a charge generation material dispersion liquid. This dispersion was applied on a polyester film on which aluminum was vapor-deposited so that the film thickness after drying was 0.1 μm, and then dried to form a charge generation layer.

Next, 10 parts of 1- [4- (N, N-diphenylamino) benzylideneimino] -2,3-dimethylindoline and 10 parts of a polycarbonate resin (trade name "Upilon Z200" manufactured by Mitsubishi Gas Chemical Co., Inc.) are used. , 1, 1,
A coating material obtained by dissolving in a mixed solvent of 36 parts of 2-trichloroethane and 54 parts of dichloromethane is applied on the charge generation layer so that the film thickness after drying is 20 μm, and then dried to form the charge transport layer. Was formed to obtain an electrophotographic photosensitive member having a photoconductive layer having the layer structure shown in FIG.

About this electrophotographic photosensitive member, an electrostatic copying paper tester (trade name "SP428" manufactured by Kawaguchi Electric Co., Ltd.)
Is used to charge the electrophotographic photosensitive member in the dark by corona discharge of −6 KV, and the surface potential V of the electrophotographic photosensitive member at this time is charged.
₀ (V) was measured. Next, the surface potential V ₁₀ (V) of the electrophotographic photosensitive member when left as it is for 10 seconds was measured. The potential holding ratio (%; (V ₁₀ / V ₀ ) × 100) of the surface potential of the electrophotographic photosensitive member was calculated from V ₀ and V ₁₀ .
Further, the surface potential V ₁₀ is exposed to light having a wavelength of 780 nm and an exposure energy of 1 μW / cm ² , and the surface potential is V ₁₀
Exposure time E _1/2 (μJ / c
m ² ) was calculated. Furthermore, the surface potential 15 seconds after the start of exposure, that is, the residual potential V _R (V) was measured.

Table 1 shows the measurement results of the dark decay and the light decay of the surface potential. In addition, the process of electrification, leaving in the dark for 1 second, exposure for 1 second, and neutralization by white light for 0.1 seconds is performed for 50 seconds.
The measurement results immediately after repeating 0 times are also shown in Table 1.

Example 4 On the charge generation layer formed in Example 3, instead of 1- [4- (N, N-diphenylamino) benzylideneimino] -2,3-dimethylindoline of Example 3 was used. , N, N'-diphenyl-N, N'-
Bis (3-methylphenyl) -1,1'-biphenyl-
An electrophotographic photoreceptor having a photoconductive layer having the layer structure shown in FIG. 1 was obtained in the same manner as in Example 3 except that 4,4′-diamine was used.

The electrophotographic characteristics of this electrophotographic photosensitive member were measured in the same manner as in Example 3, and the results are shown in Table 1.

Comparative Example 1 Indium phthalocyanine bromide was obtained according to the production example disclosed in JP-A-63-27562. That is, in a three-neck dropper equipped with a stirrer and a condenser, 87 g of diiminoisoindoline,
After adding 57 g of anhydrous indium tribromide and 700 ml of 1-methyl-2-pyrrolidinone, the mixture was heated to a reflux temperature under a nitrogen stream and reacted at the same temperature for 5 hours. The reaction mixture was filtered while hot under a nitrogen stream and then cooled to room temperature.
The residue was separated and slurried with 350 ml of ethanol for 0.5 hour, and this operation was repeated. The same operation was replaced with ethanol, and 350 ml of distilled water was used twice and 2 times with acetone.
After repeating the process once, it was dried in a vacuum oven at 110 ° C. for 24 hours to obtain 33 g of bluish violet crystalline indium phthalocyanine bromide.

The powder X-ray diffraction pattern of the indium phthalocyanine bromide thus obtained was measured by an X-ray diffractometer RAD-B system manufactured by Rigaku Denki Co., Ltd. is shown in FIG.

Comparative Example 2 An electrophotographic photosensitive member was prepared in the same manner as in Example 3, except that the indium phthalocyanine bromide of Comparative Example 1 was used in place of the indium phthalocyanine bromide of Example 3. The electrophotographic photosensitive member was evaluated in the same manner as in Example 3. The results are shown in Table 1.

[0059]

[Table 1]

As is clear from Table 1, the electrophotographic photosensitive member used in Example 3 has a high surface potential at the time of corona charging, has a good retention rate of the surface potential, and has a small half-exposure amount. The sensitivity was good. Also, 5
Even after the operation was repeated 00 times, the surface potential, the surface potential holding ratio and the sensitivity were good, and the residual potential after exposure was small.

[0061]

INDUSTRIAL APPLICABILITY The indium phthalocyanine bromide of the present invention is extremely useful as a photoconductive material for providing an electrophotographic photoreceptor having high sensitivity and excellent stability of electric characteristics during repeated use. .

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view showing an example of a layer structure that can be taken by an electrophotographic photosensitive member of the present invention.

FIG. 2 is a schematic cross-sectional view showing an example of a layer structure that the electrophotographic photosensitive member of the present invention can take.

FIG. 3 is a schematic cross-sectional view showing an example of a layer structure that the electrophotographic photosensitive member of the present invention can take.

FIG. 4 is an X-ray diffraction diagram of indium phthalocyanine bromide obtained in Example 1.

5 is an infrared absorption spectrum diagram of indium phthalocyanine bromide obtained in Example 1. FIG.

FIG. 6 is an X-ray diffraction diagram of indium phthalocyanine bromide obtained in Example 2.

FIG. 7 is an X-ray diffraction diagram of indium phthalocyanine bromide obtained in Comparative Example 1.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Conductive support 2 Charge generation layer 3 Charge transport layer 4a Photoconductive layer 4b Photoconductive layer 4c Photoconductive layer 5 Charge generation material 6 Charge transfer medium 7 Electrophotographic photoreceptor

Claims (2)

[Claims] In the X-ray diffraction diagram, the Bragg angle (2θ)
± 0.2 degree) is indium phthalocyanine bromide having diffraction peaks at 9.1 degrees, 9.7 degrees, 16.5 degrees and 27.2 degrees. 2. The Bragg angle (2θ ± 0.2 degrees) in the X-ray diffraction pattern on the conductive support is 9.1 degrees and 9.7 degrees.
An electrophotographic photoreceptor comprising a photoconductive layer containing indium phthalocyanine bromide having diffraction peaks at 16.5 degrees, 16.5 degrees and 27.2 degrees.