JP2512081B2 - R-type titanium phthalocyanine compound, method for producing the same, and electrophotographic photoreceptor using the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Field of Industrial Application) The present invention relates to a γ-type titanium phthalocyanine compound, and further uses the present optical semiconductor material having excellent exposure sensitivity characteristics and wavelength characteristics. The present invention relates to an electrophotographic photoreceptor.

(Prior Art) Conventionally, as an electrophotographic photoconductor, a photoconductor using an inorganic photoconductor such as selenium, a selenium alloy, zinc oxide, cadmium sulfide, and tellurium has been mainly used. In recent years, the development of semiconductor lasers has been remarkable, and small, stable laser oscillators have become available at low cost, and they are beginning to be used as light sources for electrophotography. However, using a semiconductor laser that oscillates short-wavelength light in these devices has many problems in terms of life, output, and the like. Therefore, materials that have been used in the short wavelength region, which have been used in the past, are not suitable for use in semiconductor lasers, and there is a need to study materials that have high sensitivity in the long wavelength region (780 nm or more). Was. Recently, research has been actively conducted on a laminated organic photoconductor in which an organic material, particularly phthalocyanine, which is expected to have sensitivity in a long wavelength region, is used and laminated. For example, divalent phthalocyanines include ε-type copper phthalocyanine (ε-CuPc), X-type metal-free phthalocyanine (X-H2Pc), τ-type metal-free phthalocyanine (τ-H2P).
c) has sensitivity in the long wavelength region. Trivalent and tetravalent metal phthalocyanines include chloroaluminum phthalocyanine (AlPcCl), chloroaluminum phthalocyanine chloride (ClAlPcCl), oxotitanium phthalocyanine (TiOPc) or chloroindium phthalocyanine (InP).
cCl) and then contacting it with vapor of a soluble solvent to increase the wavelength and sensitivity (JP-A-57-39484, JP-A-59-166959), Ti, Sn as Group IV metals And P
Long-wavelength treatment of b-containing phthalocyanine with a shift agent such as various substituents, derivatives or crown ethers (Japanese Patent Application Nos. 59-36254 and 59-20404).
No. 5) has obtained sensitivity in the long wavelength region.

An electrophotographic photoreceptor provided with a charge generation layer prepared by vapor-depositing oxotitanium phthalocyanine or indium chlorophthalocyanine on a substrate and then contacting it with a vapor of a soluble solvent is disclosed in JP-A-59-166959. Since the vapor-deposited layer is crystallized, the film thickness becomes non-uniform, causing various electrophotographic characteristics and image defects. Further, a charge generation layer was prepared using oxotitanium phthalocyanine described in JP-A-59-49544, and 2,6
An electrophotographic photosensitive member provided with a charge transfer layer composed mainly of polyester made of -dimethoxy-9,10-dihydroxyanthracene as a raw material has a high residual potential, and its usage is often restricted.

Conventionally known oxotitanium phthalocyanine is agglomerated particles that are strongly aggregated, a large amount of impurities are contained between the aggregated particles, and the crystals always grow during crystallization.
Also, due to the large pigment particle size, the charge generation layer deposited and dispersed using them lacked uniformity and dispersion stability. As a result, it was difficult to obtain a uniform charge generation layer, and it was not possible to obtain a beautiful image or a stable photoreceptor.

For example, as is clear from the X-ray diffraction patterns disclosed in JP-A-59-49544 and JP-A-59-166959, the oxotitanium phthalocyanine used has insufficient light absorption efficiency, and the charge generation is not sufficient. Decrease in carrier generation efficiency of layer,
There was a drawback that the efficiency of injecting carriers into the charge transfer layer was lowered, and that electrophotographic properties such as deterioration resistance, printing durability, and image stability during repeated use over a long period were not sufficiently satisfied.

In addition, according to JP-A-61-109056, JP-A-61-171771, and USP 4.664.997, a charge generation layer containing a titanium phthalocyanine compound and a binder polymer purified by hot water treatment and then N-methylpyrrolidone treatment was prepared. In the electrophotographic photoreceptor, the alcohols and ethers used before and after the thermal suspension treatment with N-methylpyrrolidone have strong polarities, so that the crystal particles of the titanium phthalocyanine compound strongly aggregated during the refining process. Purification becomes difficult. Acids and intermediate impurities generated during synthesis tend to remain in the agglomerated particles and on the surface, so that N-methylpyrrolidone used in the next step decomposes and causes a reaction, which inevitably reduces electrical characteristics. .

In these cases, the light absorption efficiency is not sufficient, the carrier generation efficiency of the charge generation layer is reduced, the injection efficiency of carriers into the charge transfer layer is reduced, and the deterioration resistance, printing durability, and It has a drawback that it does not sufficiently satisfy various electrophotographic characteristics such as image stability.

LEDs have also been put into practical use as digital light sources for printers. Although LEDs in the visible light range are also used, those that are generally put into practical use have an oscillation wavelength of 650 nm or more, typically 660 nm. Azo compounds, perylene compounds,
It cannot be said that selenium and zinc oxide have sufficient photosensitivity around 650 nm. The maximum sensitivity wavelength of the electrophotographic photosensitive material 1 using oxotitanium phthalocyanine as a charge generating agent that has been reported so far is only 780 to 830 (nm), and 600 to
The sensitivity of 700 (nm) was low, which was insufficient as a photoreceptor for LEDs.

(Problems to be Solved by the Invention) An object of the present invention is to provide electrophotography having excellent exposure sensitivity characteristics and spectral sensitivity, as well as deterioration resistance characteristics during repeated use over a long period of time, printing durability, and image stability. To obtain a photoconductor.

[Structure of Invention]

(Means and Actions for Solving Problems) The present invention relates to a Bragg angle (2θ) in an X-ray diffraction diagram.
± 0.2 °) 7.3 °, 17.7 °, 24.0 °, 27.2 ° and 28.6 °
Is a γ-type titanium phthalocyanine compound having a clear X-ray diffraction peak, and the X-ray diffraction peak at 27.2 ° is the strongest among these X-ray diffraction peaks, and the X-ray diffraction at the Bragg angle of 8 ° to 15 °. X with a line diffraction peak intensity of 27.2 °
It is a γ-type titanium phthalocyanine compound having a line diffraction peak intensity of 10% or less.

Further, in the electrophotographic photosensitive member using a charge generating agent and a charge transfer agent on a conductive support, the charge generating agent is the γ-type titanium phthalocyanine compound, preferably a charge generating agent. The above object was achieved by an electrophotographic photoreceptor in which the transfer agent is a styryl compound, and more specifically, the styryl compound is a compound represented by the general formula [I].

(In the formula, R ₁ and R ₂ are hydrogen atoms, alkyl groups, alkoxy groups or aryl groups, R ₃ , R ₄ and R ₅ are hydrogen atoms or -NR
₁ (R ₂ ) group is shown, and n is 0 or 1. ) The titanium phthalocyanine compound used in the present invention may have any substituent and any number of substituents. Further, it may be a single or a mixture of titanium phthalocyanine compounds having two or more chemical structural formulas.

Conventionally reported electrophotographic photoreceptors containing coarse crystalline particles in the charge generation layer have the following problems:
The number of carriers generated decreases and the photosensitivity decreases. In addition, since the charge generation layer is non-uniform, the efficiency of carrier injection into the charge transport layer is also reduced. As a result, the electrostatic characteristics cause an induction phenomenon, a decrease in surface potential, and potential stability during repeated use. A phenomenon that is unfavorable in terms of the sensitivity of the photoreceptor, such as poor image quality, occurs. In addition, the image lacks homogeneity and causes minute defects.

The oxotitanium phthalocyanine used as the charge generation layer is 2θ (± 2 °) = 9.2 °, 13.1 °, 20.7 °, 26.2 ° and 27.1 ° (θ is Bragg) by using Cukα radiation of λ = 1.5418 (AU). Angle) having an X-ray diffraction peak (JP-A-59-49544), 2θ = 7.5 °, 12.6 °, 13.0 °, 2
Those having X-ray diffraction peaks at 5.4 °, 26.2 ° and 28.6 ° (JP-A-59-166959), 2θ = 7.5 °, 12.3 °, 1.3 °, 25.
Α type having X-ray diffraction peaks at 3 ° and 28.7 °
1-239248), 2θ = 9.3 °, 10.6 °, 13.2 °, 15.1 °, 15.7
Β type having X-ray diffraction peaks at °, 16.1 °, 20.8 °, 23.3 °, 26.3 ° and 27.1 ° (Japanese Patent Laid-Open No. 62-67094; USP 4.664.997).
No.) is known, but the materials synthesized by each method and purified by a solvent have many problems for the reasons described above, and it is hard to say that they are high-quality photoreceptors. The photoconductor using the titanium phthalocyanine compound of the present invention as a charge generating agent has better sensitivity at light exposure than the above-mentioned oxotitanium phthalocyanine and has a spectral sensitivity of 600 to 800 (nm).
It shows a good value which is almost constant in the range.

The method for producing the γ-type titanium phthalocyanine compound of the present invention is shown below.

Generally, phthalocyanine is a phthalodinitrile method in which phthalodinitrile and a metal chloride are heated and melted or heated in the presence of an organic solvent, and phthalic anhydride is heated and melted with urea and a metal chloride or heated in the presence of an organic solvent. There are, but not limited to, the Wyler method, the method of reacting cyanobenzamide with a metal salt at a high temperature, and the method of reacting dilithium phthalocyanine with a metal salt. As the organic solvent, α-chloronaphthalene, β-chloronaphthalene, α-methylnaphthalene, methoxynaphthalene, diphenylethane, ethylene glycol, dialkyl ether, quinoline, sulfolane, dichlorobenzene, N-methyl-2-pyrrolidone, dichlorotoluene. A solvent having a high boiling point that is inert to the reaction, such as That is, the titanium phthalocyanine compound of the present invention is, for example, phthalodinitrile and titanium compound (preferably titanium tetrachloride which is low in by-product and low in cost) and heated and stirred in the temperature range of 150 to 300 ° C. in the above organic solvent. Can be synthesized. Also, instead of phthalodinitrile, an indoline compound such as diiminoisoindoline, or 1
An indolenine compound such as -amino-3-iminoisoindolenine can also be used, and the titanium compound is not limited to titanium tetrachloride and may be titanium trichloride, titanium tetrabromide or the like.

The titanium-containing phthalocyanine used in the present invention is the Moser and Thomas “Phthalocyanine Compound”.
s ") and other known methods and compounds obtained by the above-mentioned appropriate methods are used as acids, alkalis, acetone, methyl ethyl ketone, tetrahydrofuran, pyridine, quinoline, sulfolane, α-chloronaphthalene, toluene, dioxane, xylene, chloroform, tetrachloromethane, It is obtained by purification with carbon chloride, dichloromethane, dichloroethane, trichloropropane, N, N'-dimethylacetamide, N-methylpyrrolidone, N, N'-dimethylformamide, etc. Purification methods include washing, recrystallization and soxhlet. It is also possible to purify by sublimation, etc. The purification method is not limited to these, and the action of removing unreacted substances, reaction by-products and impurities Any of them will do.

The titanium phthalocyanine compound according to the present invention is a phthalocyanine compound whose main nucleus is TiO 2. However, TiCl _2, TiBr but those centered core ₂ or the like can be used as starting materials, TiCl _2, TiBr ₂ to easily central core by various processing is TiO
It is difficult to stably obtain those whose cores are etc. Further, the titanium phthalocyanine compound may be a low halogenated titanium phthalocyanine compound.

The titanium phthalocyanine compound obtained by the above method does not have sufficient sensitivity and various characteristics.
Therefore, the target crystal can be obtained by further adding the crystal transition step. The γ-type titanium phthalocyanine compound of the present invention preferably has a primary particle size of 0.2 μm or less, and when it is used as a charge generating agent, it is preferably further refined by a mechanical grinding method.

The titanium phthalocyanine compound of this method requires a step of making the particles uniform for the purpose of improving the coatability of the charge generation layer and stably obtaining high sensitivity. That is, particles immediately after chemical treatment of titanium phthalocyanine compound, or particles whose crystals have been adjusted with alcohol, halogen, ether, cellusolve-based solvent after treatment are adjusted by adding mechanical straining force and shearing force. To be done.

The equipment used is a kneader, Banbury mixer, attritor, edge runner mill, roll mill, ball mill, sand mill, SPEX mill, homomixer, disperser, agitator, jaw crusher,
There are stamp mills, cutter mills, micronizers, etc., but not limited to these.

Examples of the dispersion medium used include glass beads, steel beads, zirconia beads, alumina balls, zirconia balls, steel balls, and flint stone, but they are not always necessary.

In addition, if necessary, it is possible to use a grinding aid such as salt or Bog's salt. For the particle adjustment, a dry method in which strain or shearing force is most efficiently applied to the sample or a wet method in which uniform adjustment of particles is easy is selected. The wet method uses a liquid solvent during milling. For example, at least one selected from alcohol solvents such as methanol, ethanol, butanol, glycerin, ethylene glycol, diethylene glycol, polyethylene glycol, halogen solvents, cellosolve solvents, ether solvents and the like.

In order to obtain the titanium phthalocyanine compound of the present invention, a temperature of 50 ° C or lower is preferable. The temperature rises to 40 to 50 ° C due to the heat generated during milling, but a stable temperature can be obtained by continuing milling without external heating. That is, the crystal plane of the X-ray diffraction peak of the titanium phthalocyanine compound of the present invention can be obtained by suppressing the crystal growth by heating and transferring the crystal by milling.

The charge generation layer using the titanium phthalocyanine compound obtained according to the present invention is a uniform layer having a high light absorption efficiency, and it is formed between particles in the charge generation layer, between the charge generation layer and the charge transfer layer, and below the charge generation layer. There are few voids between the pulling layer or the conductive substrate, and the characteristics as an electrophotographic photosensitive member such as potential stability and prevention of rise in bright area potential during repeated use, reduction of image defects, printing durability, etc. ， It is possible to obtain an electrophotographic photoreceptor that satisfies many requirements.

The n-type photoreceptor is formed by sequentially laminating an undercoat layer, a charge generation layer, and a charge transfer layer on a conductive substrate. The p-type photoconductor is prepared by stacking a charge transfer layer and a charge generation layer on an undercoat layer in this order, or by dispersing and coating a charge transfer agent and a charge transfer agent together with an appropriate resin on the undercoat layer. There was something that was done. If necessary, an overcoat layer can be provided on both photoconductors for the purpose of protecting the surface and preventing filming with toner. Also, the undercoat layer can be removed if not necessary.

The titanium phthalocyanine compound of the present invention is preferably used for all the above-mentioned various photoconductors. The charge generation layer can be obtained by dispersion-coating a titanium phthalocyanine compound and a resin with an appropriate solvent, but if necessary, it can be used by dispersion-coating only the solvent without the resin.

The titanium phthalocyanine compound of the present invention is
When a dispersion coating liquid is formed with a resin and a solvent, some crystal transitions may occur, but a mixture of the γ-type crystal form and other crystal forms can also be used. Further, a crystal transition inhibitor may be used in combination.

Although it is known that the charge generation layer is obtained by vapor deposition, the material obtained by the present invention is extremely efficient in vapor deposition because fine primary particles are processed and impurities existing between particles are removed. It is also effective as a vapor deposition material.

Coating of photoreceptor is done by spin coater, applicator,
Spray coater, bar coater, immersion coater, doctor blade, roller coater, curtain coater,
Use a bead coater device. Drying is 40 to 200
C., 10 minutes to 6 hours, under static or blown conditions. After drying the film thickness is 0.01 to 5 microns, preferably 0.1
To 1 micron.

The binder that can be used when forming the charge generation layer by coating can be selected from a wide range of insulating resins, and can also be selected from organic photoconductive polymers such as poly-N-vinylcarbazole, pyrivinylanthracene and pyrivinylpyrene. . Preferably, polyvinyl butyral, polyarylate (condensation polymer of bisphenol A and phthalic acid, etc.), polycarbonate, polyester, phenoxy resin, polyvinyl acetate, acrylic resin, polyacrylamide resin, polyamide resin, polyvinyl pyridine, cellulosic resin, urethane Resin, epoxy resin, silicone resin, polystyrene, polyketone resin, polyvinyl chloride,
Vinyl chloride-vinyl chloride copolymer, polyvinyl acetal, polyvinyl formal, polyacrylonitrile, phenol resin, melamine resin, casein, polyvinyl alcohol,
An insulating resin such as polyvinylpyrrolidone can be used. The resin contained in the charge generation layer is 100% by weight or less,
It is preferably 40% by weight or less. These resins may be used alone or in combination of two or more. The solvent for dissolving these resins differs depending on the type of the resin, and it is preferable to select a charge generation layer or an undercoat layer, which will be described later, from those that do not affect the coating. Specifically, aromatic hydrocarbons such as benzene, xylene, ligroin, monochlorobenzene, dichlorobenzene, ketones such as acetone, methyl ethyl ketone, cyclohexanone, alcohols such as methanol, ethanol, isopropanol, ethyl acetate, methyl cellosolve, etc. Esters, carbon tetrachloride, chloroform, dichloromethane, dichloroethane, trichloroethylene and other aliphatic halogenated hydrocarbons, tetrahydrofuran, dioxane, ethylene glycol monomethyl ether and other ethers,
Amides such as N, N-dimethylformamide and N, N-dimethylacetamide, and sulfoxides such as dimethylsulfoxide are used. The charge generation layer can also be formed by a vapor deposition method, which is vapor-deposited under a vacuum of about 10 ^-5 to 10 ^-6 Torr and has a film thickness of 0.01 to 5 μm, preferably 0.05 to 0.5
μm is good.

The charge transfer layer is formed by dissolving and dispersing the charge transfer agent alone or in a binder resin. The charge transfer substance is preferably a styryl compound, preferably the compound represented by the above general formula [I], but any substance having a charge transfer ability may be used. Other than styryl-based compounds, hydrazone-based, pyrazoline-based, oxazole-based, oxadiazole-based, stilbene-based, thiazole-based, triarylmethane-based, carbazole-based compounds and the like are mentioned, but are not limited thereto. Also, these potential transfer agents may be used alone or in combination.
A combination of two or more species can be used. The binder used in the charge transfer layer is selected from the above resins used in coating the charge generation layer. Solvents that dissolve the resin and charge transfer agent are also selected from the above solvents. Two or more kinds of resins and solvents can be used in combination.

The film thickness after drying is 5 to 50 μm, preferably 10 to 20 μm
What is coated so that it becomes. In addition to these layers, an undercoat layer can be provided on the conductive substrate for the purpose of preventing a decrease in chargeability and improving adhesion. As a subbing layer, nylon 6, nylon 66, nylon 11, nylon 610,
Copolymerized nylon, polyamide such as alkoxymethylated nylon, casein, polyvinyl alcohol, nitrocellulose, ethylene-acrylic acid copolymer, gelatin, polyurethane, polyvinyl butyral and metal oxides such as aluminum oxide are used. It is also possible to adjust by incorporating a metal oxide such as zinc oxide and titanium oxide, conductive and inductive particles such as silicon nitride, silicon carbide and carbon Bragg into the resin.

The material of the present invention has an absorption peak at a wavelength of 600 to 800 nm, and is suitable not only for use as an electrophotographic photoreceptor in copying machines and printers, but also as an absorption material for solar cells, photoelectric conversion elements and optical disks.

(Examples) Examples of the present invention will be specifically described below. Parts in the examples indicate parts by weight.

Examples 1 to 7 Phthalodinitrile 20.4 parts and titanium tetrachloride 7.6 parts were heated and reacted in quinoline 150 parts at 220 ° C. for 4 hours, and then the solvent was removed by steam distillation. Then, the product was purified with a 2% aqueous solution of hydrochloric acid and then with a 2% aqueous solution of sodium hydroxide and then with acetone, and the sample was dried to obtain 21.3 parts of oxytitanium phthalocyanine (TiOPc).

10 parts of this TiOPc is gradually dissolved in 200 parts of 97% sulfuric acid at 2 ° C., and the mixture is stirred for 1 hour while keeping the temperature at 5 ° C. or lower. Then, this sulfuric acid solution is slowly poured into 2000 parts of ice water stirred at a high speed to filter the precipitated crystals.
The crystals were washed with distilled water until no acid remained, and then dried to obtain 9.6 parts of a sample.

The sample obtained by the above method was crystallized into γ-type TiOPc by the method and conditions shown in Table 1.

The samples prepared under the conditions shown in Table 1 were measured by X-ray diffraction and
After confirming the transfer to the mold, it was taken out of the grinder and washed with 2% dilute sulfuric acid and 2% ammonium hydroxide. The samples of Examples 1 to 7 obtained by the above method were all Bragg angles (2θ ± 0.2 °) of 7.3 °, 17.7 °, 24.0 °, 2
Γ with distinct X-ray diffraction peaks at 7.2 ° and 28.6 °
It was a type titanium phthalocyanine compound. The primary particle sizes of the samples obtained in Examples 1 to 7 are all 0.
The particles were uniform particles of 2 μm or less.

The X-ray diffraction patterns of the γ-type titanium phthalocyanine compounds produced in Examples 1 to 7 measured using CuKα rays are shown in FIGS. 1 to 7.

Next, a method for producing an electrophotographic photoreceptor using the γ-type titanium phthalocyanine compound produced in Examples 1 to 7 as a charge generating agent will be described.

Polyethylene terephthalate (PE) was prepared by mixing 10 parts of copolymerized nylon (Amylan CM-8000 manufactured by Toray) with 190 parts of ethanol in a ball mill for 3 hours and dissolving.
T) On the sheet where aluminum is vapor-deposited on the film,
After applying with a wire bar, it was dried to obtain a sheet having an undercoat layer with a film thickness of 0.5 μm.

2 parts of the γ-type titanium phthalocyanine compound obtained in this example was sufficiently miniaturized with a sand mill, and then 97 parts of THF and 1 part of vinyl chloride-vinyl acetate copolymer resin (VMCH manufactured by Union Carbide Co.)
Was dispersed in a ball mill for 6 hours together with the resin solution in which

This dispersion is applied on the undercoat layer, dried and
A micron charge generation layer was formed.

Next, as a charge transfer agent, 1 part of an exemplified compound (Ia) of the compound of the general formula [I], 1 part of a polycarbonate resin (Panlite L-1250 manufactured by Teijin Chemicals Ltd.) and 8 parts of methylene chloride were used.
The mixture was mixed and dissolved in parts. This solution was applied on the charge generation and dried, then a charge transfer layer of 15 μm was formed, and the electrophotographic characteristics were measured.

The electrophotographic characteristics of the photoreceptor were measured by the following method.

Electrostatic copying paper tester SP-428 (made by Kawaguchi Denki)
Static mode 2, corona charging is -5.2KV, surface potential and 5Lux white light or 1μW of light adjusted to 800nm is applied, and white light half exposure sensitivity ( E1 / 2) was investigated. As a charge transfer agent (I
Second, the electrophotographic characteristics of the electrophotographic photosensitive member using
Shown in the table.

From the results in Table 2, it was confirmed that the γ-type titanium phthalocyanine compound of the present invention has extremely excellent sensitivity as a charge generating material for an electrophotographic photoreceptor.

Comparative Example 1 20.4 parts of phthalodinitrile and 7.6 parts of titanium tetrachloride were added at 230 ° C.
After stirring in 150 parts of α-chloronaphthalene for 3 hours at
It was allowed to cool, filtered while hot at 100 to 130 ℃, and heated to 100 ℃.
Wash with chloronaphthalene. After filtering with methanol, washing with water is repeated until the pH becomes 6-8.

The obtained wet cake was added to N-methylpyrrolidone.
After heating and stirring at 140 to 150 ° C. for 2 hours, the mixture was filtered, washed with methanol, and dried to obtain 15.8 parts of TiOPc. When the X-ray diffraction pattern of this TiOPc was measured, it had the β-type X-ray diffraction pattern shown in FIG. Further, a photoconductor was prepared in the same manner as in Example 1 by using this TiOPc as a charge generating agent, and the electrophotographic characteristics were measured.

Comparative Example 2 20.4 parts of phthalodinitrile and 7.6 parts of titanium tetrachloride were added at 220 ° C.
After stirring in 150 parts of α-chloronaphthalene for 3 hours at
I passed. Further, the mixture was heated under reflux with 200 parts of concentrated ammonia water for 1 hour, washed with acetone, and then dried to 20.0.
Part of TiOPc was obtained. The X-ray diffraction pattern of this TiOPc is shown in FIG. From the X-ray diffraction peak, it was found to be α type. Using this TiOPc as a charge generating agent, a photoconductor was prepared in the same manner as in Example 1 and the electrophotographic characteristics were measured. The result is the third
Shown in the table.

From the above results, it is understood that the β and α type TiOPc of Comparative Examples 1 and 2 are inferior in sensitivity to the γ type TiOPc.

The absorption spectra of the charge generation layers of the electrophotographic photoreceptors prepared in Example 1 and Comparative Examples 1 and 2 are shown in FIGS. 10, 11 and 12, respectively. The gamma type of Example 1 has a range of 600 to 820 nm,
Although almost constant absorption values are obtained, the β-type of Comparative Example 1 has λmax = 770 nm, and the α-type of Comparative Example 2 has λmax = 830 nm, which has a constant absorption in the range of 600 to 800 nm. There were no drawbacks.

FIG. 13 shows the spectral sensitivity of the electrophotographic photoconductors produced in Example 1 and Comparative Examples 1 and 2. In Example 1 in which γ-type TiOPc was used as the charge generation agent, it had a substantially constant high sensitivity in the range of 600 to 800 nm. Further, the photoconductors produced in Examples 1 to 7 were mounted on a commercially available copying machine and subjected to an image test. As a result, extremely good images were obtained.

〔The invention's effect〕

By using the γ-type octitanium phthalocyanine compound obtained by the present invention as a charge generating agent, it was possible to obtain an electrophotographic photoreceptor having high sensitivity and good stability in repeated use. As a result, it is possible to obtain a stable and beautiful image.
High sensitivity in semiconductor lasers and LEDs
It is most suitable as a photoconductor for a printer that uses as a light source.

[Brief description of drawings]

1 to 7 are X-ray diffraction patterns measured using CuKα rays of the γ-type titanium phthalocyanine compounds produced in Examples 1 to 7, respectively, and FIG. 8 is a β-type Ti produced in Comparative Example 1.
X-ray diffraction pattern of OPc, FIG. 9 shows α-type TiO 2 prepared in Comparative Example 2.
X-ray diffraction pattern of Pc, FIGS. 10, 11 and 12 are absorption spectra of charge generation layers of the photoconductors prepared in Example 1, Comparative Examples 1 and 2,
FIG. 13 shows the spectral sensitivities of the photoconductors of Example 1, Comparative Examples 1 and 2, respectively.

Claims (7)

(57) [Claims] 1. A Bragg angle (2
θ ± 0.2 °) 7.3 °, 17.7 °, 24.0 °, 27.2 ° and 2
A γ-type titanium phthalocyanine compound having a clear X-ray diffraction peak at 8.6 °. 2. On the X-ray diffraction diagram, the Bragg angle (2
θ ± 0.2 °) 7.3 °, 17.7 °, 24.0 °, 27.2 ° and 2
It has a clear X-ray diffraction peak at 8.6 °, of which 27.2 °
Has the strongest X-ray diffraction peak and a Bragg angle of 8
The intensity of the X-ray diffraction peak at ° to 15 ° is 10% or less of the intensity of the X-ray diffraction peak at 27.2 ° γ
Type titanium phthalocyanine compound. 3. The γ-type titanium phthalocyanine compound according to claim 1, wherein the compound crystal has a primary particle diameter of 0.2 μm or less. 4. An electrophotographic photoreceptor comprising a charge generating agent and a charge transferring agent on a conductive support, wherein the charge generating agent is the γ-type titanium phthalocyanine compound according to any one of claims 1 to 3. And an electrophotographic photoreceptor. 5. An electrophotographic photosensitive member comprising a conductive support and a charge generating agent and a charge transfer agent, wherein the charge generating agent is the γ-type titanium phthalocyanine compound according to any one of claims 1 to 3. An electrophotographic photoreceptor, wherein the agent is a styryl compound. 6. The electrophotographic photosensitive member according to claim 5, wherein the styryl compound is a compound represented by the general formula [I]. (In the formula, R ₁ and R ₂ are hydrogen atoms, alkyl groups, alkoxy groups or aryl groups, R ₃ , R ₄ and R ₅ are hydrogen atoms or -NR ₁
(R ₂ ) group is shown, and n is 0 or 1. ) 7. The electrophotographic photosensitive member according to claim 4, which has an inorganic or organic intermediate layer on the conductive support.