JP2985254B2 - Electrophotographic photoreceptor - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a high-performance electrophotographic photosensitive member.

(Prior art) With the development of non-impact printer technology in recent years, electrophotography optical printers capable of high image quality and high speed using laser light or LED as a light source are becoming widespread. The development of a photoreceptor that can be endured is active.

In particular, when a laser is used as a light source, a semiconductor laser is often used, but the oscillation wavelength is limited to a relatively long wavelength in the near infrared region. Therefore, a photoreceptor having sensitivity in the visible region, which has been conventionally used in electrophotography, is inappropriate to be used for a semiconductor laser, and a photoreceptor having photosensitivity up to the near infrared region is required. I have.

As an organic material satisfying this requirement, conventionally, indoline-based dyes, polyazo-based dyes, phthalocyanine-based dyes, naphthoquinone-based dyes, and the like are known, but indoline-based dyes can have a longer wavelength, but lack practical stability. It is difficult to increase the wavelength of polyazo dyes, and there is a disadvantage in production.
At present, naphthoquinone dyes have difficulty in sensitivity. In contrast, phthalocyanine dyes have a peak in spectral sensitivity in the long wavelength region of 600 nm or more, and have high sensitivity, and the spectral sensitivity changes depending on the type of central metal and crystal form. It is considered suitable and is under research and development.

In recent years, the use of titanyl phthalocyanine having electrophotographic characteristics with relatively high photosensitivity has been studied (JP-A-59-49544, JP-A-61-23928, and JP-A-61-23928).
Nos. 1090564 and 62-275272), it is known that there are differences in characteristics depending on various crystal forms. In order to produce these various crystal forms, special purification and special solvent treatment are required. The treatment solvent is different from that used when forming the dispersion coating film. This is because the various crystals obtained are easy to grow in the growth treatment solvent,
If the same solvent is used as a coating solvent, it is difficult to control the crystal form and particle size, and the coating composition is not stable. As a result, the electrostatic properties are deteriorated, which is not suitable for practical use. For this reason, a chlorine-based solvent such as chloroform, which does not easily promote the crystal growth, is usually used when forming a coating material. However, these solvents do not always have good dispersibility in titanyl phthalocyanine, and are problematic in terms of the dispersion stability of the paint.

On the other hand, various photoreceptors utilizing a hydrazone compound, a butadiene compound, poly-N-vinylcarbazole, etc. as a hole transporting substance as a charge transporting material have been proposed, and some of them have been put to practical use. However, among them, those containing a hydrazone compound have excellent electrical properties, but have a problem of deterioration due to light fatigue. In addition, titanyl phthalocyanine generally has a large ionization potential, and when used together with a material such as a hydrazone compound having a small ionization potential, the difference in ionization potential is large.
Since the injection of holes from the titanyl phthalocyanine into the hydrazone compound easily occurs, the chargeability is reduced, and the surface potential is significantly reduced due to repeated use and light fatigue. Even in the case of using a photoreceptor of a dispersion system containing a charge generation material and a charge transfer material in a single layer, there is a problem that it is difficult to include a large amount of the charge generation material for improving the sensitivity while maintaining the chargeability. . Those containing a butadiene compound as a main component are resistant to light fatigue, but have drawbacks in electrical characteristics.
Further, the hydrazone compound and the butadiene compound do not have a film-forming property and are used after being dissolved in a suitable solvent together with the resin (binder). When poly-2,3-epoxypropylcarbazole is used alone, the film-forming property is poor, and the ionization potential is larger than that of phthalocyanine, so that injection of holes is less likely to occur, so that the mobility in negative charging is slow and the residual potential tends to accumulate. is there.

(Problems to be Solved by the Invention) The present invention has been made in view of the above-mentioned conventional circumstances, and has as its object to have a crystal stability in a solvent used for forming a coating, and a dispersing property. And to provide an electrophotographic photoreceptor having good light sensitivity. Another object of the present invention is to provide an electrophotographic photoreceptor having photosensitivity suitable for a semiconductor laser and capable of controlling characteristics by using an organic photoconductive material in combination.

(Means for Solving the Problems) In order to achieve the above object, in the electrophotographic photoreceptor according to the present invention, a stable crystal form is obtained by using a novel titanyl phthalocyanine composition crystal and an α-type titanyl phthalocyanine crystal. A photoconductor having high sensitivity characteristics can be obtained. Furthermore, by using a charge transfer material obtained by combining poly-2,3-epoxypropylcarbazole with a hydrazone compound and / or a butadiene compound, a high-sensitivity electrophotographic photoreceptor having excellent electrical characteristics can be obtained. .

Among the charge generation materials used in the present invention, phthalocyanine compounds and naphthalocyanine compounds are known methods such as Moser and Thomas's "phthalocyanine compound" (Linehold Co., Ltd., 1963) and "phthalocyanine" (CRC publication 1983) and other known methods. Use those obtained by an appropriate method.

For example, titanyl phthalocyanine can be easily synthesized from 1,2-dicyanobenzene (o-phthalodinitrile) or a derivative thereof and a metal or metal compound according to a known method.

For example, in the case of oxytitanium phthalocyanines,
It can be easily synthesized according to the reaction formula shown in the following (1) or (2).

Nitrobenzene, quinoline, α-
High-boiling organic solvents which are inert to the reaction such as chloronaphthalene, β-chloronaphthalene, α-methylnaphthalene, methoxynaphthalene, diphenylether, diphenylmethane, diphenylethane, ethylene glycol dialkyl ether, diethylene glycol dialkyl ether, and triethylene glycol dialkyl ether are preferred. The reaction temperature is usually from 150 ° C to 300 ° C, particularly preferably from 200 ° C to 250 ° C.

In the present invention, the crude titanyl phthalocyanine compound thus obtained is treated with tetrahydrofuran after the non-crystallization treatment. At that time, after removing the organic solvent used for the condensation reaction using an appropriate organic solvent in advance, for example, an alcohol such as methanol, ethanol, or isopropyl alcohol, or an ether such as tetrahydrofuran or 1,4-dioxane, Water treatment is preferred. In particular, it is preferable to wash until the washing liquid pH after the hot water treatment becomes about 5 to 7.

Subsequently, 2-ethoxyethanol, diglyme,
It is more desirable to treat with an electron-donating solvent such as 1,4-dioxane, tetrahydrofuran, N, N-dimethylformamide, N-methylpyrrolidone, pyridine and morpholine.

Examples of the phthalocyanine nitrogen isotope include various porphines, for example, tetrapyridinoporphyrazine in which one or more benzene nuclei of phthalocyanine are replaced with a quinoline nucleus, and metal phthalocyanines include
Various materials such as copper, nickel, cobalt, zinc, tin, aluminum, and titanium can be mentioned.

Further, phthalocyanines and naphthalocyanines as a substituent include an amino group, a nitro group, an alkyl group, an alkoxy group, a cyano group, a mercapto group, a halogen atom, and the like, a sulfonic acid group, a carboxylic acid group, and a metal salt thereof. ,
Ammonium salts, amine salts and the like can be exemplified as relatively simple ones. Furthermore, various substituents can be introduced into the benzene nucleus via an alkylene group, a sulfonyl group, a carbonyl group, an imino group, and the like, and these are conventionally known as an anti-aggregation agent or a crystal conversion inhibitor in the technical field of these phthalocyanine pigments. (For example, see U.S. Pat. Nos. 3,973,981 and 4,088,507).

In the present invention, the composition ratio of titanyl phthalocyanine and a phthalocyanine nitrogen isoform or a metal-free and metal phthalocyanine which may have a substituent on the benzene nucleus, and a metal-free and metal naphthalocyanine which may have a substituent on the naphthyl nucleus are: The ratio may be 100/50 (weight ratio) or more, but is desirably 100/20 to 0.1 (weight ratio). Above this ratio, the crystals will contain many single crystals in addition to the mixed crystal composition, and it will be difficult to identify the novel material of the present invention in the infrared absorption spectrum or X-ray diffraction image (hereinafter, these mixed compositions Is referred to as a titanyl phthalocyanine composition.)

The amorphous titanyl phthalocyanine composition can be obtained by a single chemical method or mechanical method, but more preferably by a combination of various methods. For example, non-crystalline particles can be obtained by weakening agglomeration between particles by a method such as an acid pasting method or an acid slurry method and then grinding by a mechanical treatment method.
The equipment used during grinding is kneader, Banbury mixer, attritor, edge runner mill, roll mill, ball mill, sand mill, homomixer, SPEX
Examples include, but are not limited to, mills, dispersers, agitators, jaw crushers, stamp mills, cutter mills, micronizers, and the like. The acid pasting method, which is well known as a chemical treatment method, is a method in which a pigment is dissolved in 95% or more sulfuric acid or a sulfate is poured into water or ice water to reprecipitate. Is desirably maintained at 5 ° C. or lower, and sulfuric acid is slowly injected into the rapidly stirred water,
Further, amorphous particles can be obtained under good conditions.

In addition, there are a method of directly grinding the crystalline particles by mechanical treatment for an extremely long time, and a method of treating the particles obtained by the acid pasting method with the above-mentioned solvent or the like and then grinding.

Amorphous particles can also be obtained by sublimation. For example,
Raw materials obtained by various methods under vacuum 500 ° C ~ 6
It can be obtained by sublimation by heating to 00 ° C. and rapid co-evaporation deposition on a substrate.

The amorphous titanyl phthalocyanine composition obtained as described above is treated in tetrahydrofuran,
Obtain new stable crystals. As a method for treating tetrahydrofuran, 5-300 parts by weight of tetrahydrofuran is added to 1 part by weight of the amorphous titanyl phthalocyanine composition and stirred in various stirring tanks. The temperature can be either heating or cooling, but heating will speed up the crystal growth,
Slow at low temperatures. As the stirring tank, in addition to a normal stirrer, an ultrasonic ball mill, a sand mill, a homomixer, a disperser, an agitator, a micronizer and the like, which are used for dispersion, and a mixer such as a concal blender V-type mixer are appropriately used. However, it is not limited to these. After these stirring steps, filtration, washing and drying are usually performed to obtain stabilized titanyl phthalocyanine crystals. At this time, a resin or the like can be added to the dispersion liquid as required without filtering and drying to form a coating material. When used as a coating film of an electrophotographic photoreceptor or the like, the process is omitted and is extremely effective. The infrared absorption spectrum of the titanyl phthalocyanine composition of the present invention thus obtained is shown in the first.
Shown in the figure. This titanyl phthalocyanine composition has an absorption wave number (cm ⁻¹ , which includes an error of ± 2) of 16.
09, 1480, 1458, 1365, 1332, 1165, 1072, 961, 876,
It shows a characteristic strong peak at point 730.

FIG. 4 shows an X-ray diffraction pattern using CuK. This titanyl phthalocyanine composition showed a maximum peak at 27.3 degrees in the X-ray diffraction diagram at a Bragg angle 2θ (including an error range of ± 0.2 degrees), and showed a peak at 9.7 degrees and 29.7 degrees.
One showing a strong peak at 4.1 degrees and the largest peak at 27.3 degrees, 7.4 degrees, 9.7 degrees, 11.7 degrees, 13.3 degrees, 15.0 degrees, 2
Some show strong peaks at 4.1 degrees and 28.5 degrees. These differences are generally considered to be due to the fact that the intensity of the diffraction line is substantially proportional to the size of each crystal face, and therefore the degree of growth of each crystal face of the same structure crystal is different.

The titanyl phthalocyanine composition of the present invention is a very stable and excellent crystal which does not show a large change in the infrared absorption spectrum even when the crystal growth is promoted by further heating and stirring in tetrahydrofuran.

Next, α-type titanyl phthalocyanine can be obtained by subjecting the obtained crude titanyl phthalocyanine compound to an amorphous treatment, followed by a treatment with methyl ethyl ketone, and a treatment similar to the case of the titanyl phthalocyanine composition. FIG. 2 shows the infrared absorption spectrum of the α-type titanyl phthalocyanine thus obtained. This α-type titanyl phthalocyanine has an absorption wave number (cm ⁻¹ , including an error of ± 2) of 1611, 1476, 1463, 1430, 1335, 1168, 10
Strong peaks at 60, 971, 965, 940, 879, 839 and 773 are characteristic points.

FIG. 5 shows an X-ray diffraction pattern using CuK. This α-type titanyl phthalocyanine has a Bragg angle 2θ (including an error range of ± 0.2 degrees) of 7.5 degrees, 10.2 degrees, 12.6 degrees, 16.3 degrees, and 18.3 in an X-ray diffraction diagram.
It shows strong peaks at degrees, 22.4 degrees, 24.3 degrees, 25.4 degrees, and 28.6 degrees.

By mixing with the titanyl phthalocyanine composition of the present invention, α-type titanifurthalocyanine does not show a large change in the infrared absorption spectrum even when heating and stirring are further added in tetrahydrofuran, and crystal growth is promoted.
Very stable and good crystals.

By coating titanyl phthalocyanine with a suitable binder as the charge generation layer of the present invention, a charge generation layer having extremely good dispersibility and extremely high photoelectric conversion efficiency can be obtained.

Coating is performed using a spin coater, an applicator, a spray coater, a bar coater, an immersion coater, a doctor blade, a rotor coater, a curtain coater, a bead coater device, and drying is desirably heated to 40 to 200 ° C. for 10 minutes. It is performed under static or blowing conditions for a period of up to 6 hours. After drying, the film thickness is 0.01 to 5 μm, preferably 0.1 μm.
Coating is performed so as to be 1 to 1 μm.

The mixing ratio between the titanyl phthalocyanine composition and the α-type titanyl phthalocyanine is 100%.
Α-type titanyl phthalocyanine is 5 to 100 parts by weight
Parts by weight, preferably 20 to 80 parts by weight.

The resin that can be used when forming the charge generation layer by coating can be selected from a wide range of insulating resins, and can be selected from organic photoconductive polymers such as polyvinyl anthracene and polyvinyl pyrene. Also preferably, polyvinyl butyral, polyarylate (such as a condensation polymer of bisphenol A and phthalic acid), polycarbonate, polyester, phenoxy resin, polyvinyl acetate, acrylic resin,
Polyacrylamide resin, polyamide, polyvinyl pyridine, cellulose resin, urethane resin, epoxy resin, silicone resin, polystyrene, polyketone, polyvinyl chloride, polyvinyl chloride copolymer, polyvinyl acetal, polyacrylonitrile, phenol resin, melamine resin, Examples include insulating resins such as casein and polyvinylpyrrolidone. The resin contained in the charge generation layer is
100% by weight or less, preferably 40% by weight or less is suitable. 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 is preferably selected from those that do not affect the charge transfer layer or the undercoat layer described later. Specifically, aromatic hydrocarbons such as benzene, xylene, ligroin, monochlorobenzene and dichlorobenzene, ketones such as acetone, methyl ethyl ketone and cyclohexanone, alcohols such as methanol, ethanol and isopropanol, acetate esters and methyl cellosolve etc. Esters, carbon tetrachloride, chloroform, dichloromethane, dichloroethane, fatty halogenated hydrocarbons such as trichlorethylene, tetrahydrofuran, 1,4-dioxane, ethers such as ethylene glycol monomethyl ether, N, N-dimethylformamide, Amides such as N, N-dimethylacetamide and sulfoxides such as dimethylsulfoxide are used.

Hole transporting substance (charge transporting material) used in the present invention
One of them is poly-2,3- represented by the following structural formula [A].
Epoxypropyl carbazole.

The other is a hydrazone compound represented by the following general formula [I], Preferred specific examples are as follows.

[P-dimethylaminobenzaldehyde- (diphenylhydrazone)] [P-Diethylaminobenzaldehyde- (diphenylhydrazone)] [P-diphenylaminobenzaldehyde- (diphenylhydrazone)] [P-Dibenzylaminobenzaldehyde- (diphenylhydrazone)] [P- (benzyl-methoxyphenyl) aminobenzaldehyde- (diphenylhydrazone)] [O-methyl-p-diethylaminobenzaldehyde-
(Diphenylhydrazone)] [O-methyl-p-dibenzylaminobenzaldehyde- (diphenylhydrazone)] [O-methoxy-p-diethylaminobenzaldehyde- (diphenylhydrazone)] [O-benzyloxy-p-diethylaminobenzaldehyde- (diphenylhydrazone)] [P-Diethylaminobenzaldehyde- (methyl-phenylhydrazone)] [O-methyl-p-dibenzylaminobenzaldehyde- (methyl-phenylhydrazone)] [O-methyl-p-dibenzylaminobenzaldehyde- (benzyl-phenylhydrazone)] A butadiene compound represented by the following general formula [II], Preferred specific examples are as follows.

[1,1-bis- (p-dimethylaminophenyl) -4,4-
Diphenyl-1,3-butadiene] [1,1-bis- (p-diethylaminophenyl) -4,4-
Diphenyl-1,3-butadiene] Among the hydrazone compounds and butadiene compounds, p-diethylaminobenzaldehyde-
(Diphenylhydrazone), p-diphenylaminobenzaldehyde- (diphenylhydrazone) or o-methyl-p-dibenzylaminobenzaldehyde- (diphenylhydrazone), and 1,1-bis- (p-diethylaminophenyl) -4,4 -Diphenyl-1,3-butadiene.

The electrophotographic photoreceptor of the present invention is obtained by dissolving poly-2,3-epoxycarbazole, a hydrazone compound of the general formula [I] and a butadiene compound of the general formula [II] together with a resin (adhesive) in a suitable solvent, Photoconductive substances that absorb light and generate electric charges as necessary, sensitizing dyes, electron-absorbing materials,
A coating solution obtained by adding various additives such as a deterioration preventing substance or a plasticizer is coated on a conductive substrate, dried, and then dried.
A photosensitive layer having a thickness of about 30 μm can be formed. The mixing ratio of poly-2,3-epoxypropylcarbazole and a hydrazone compound, or a butadiene compound, or a combination group of a hydrazone compound and a butadiene compound, and the resin is 30 to 300 parts by weight, preferably 100 parts by weight of the resin. Is 50 to 200 parts by weight. Furthermore, the mixing ratio of the hydrazone compound or the butadiene compound, or the combination group of the hydrazone compound and the butadiene compound, and the poly-2,3-epoxycarbazole is such that the hydrazone compound, the butadiene compound, or the hydrazone compound and the butadiene compound, 3 to 1000 parts by weight of poly-2,3-epoxypropylcarbazole to parts by weight
Parts by weight, preferably 10 to 100 parts by weight. The resin used for the charge transfer layer is a silicone resin, a ketone resin,
Insulating resins such as polymethyl methacrylate, polyvinyl chloride, acrylic resin polyarylate, polyester, polycarbonate, polystyrene, acrylonitrile-styrene copolymer, acrylonitrile-butadiene copolymer, polyvinyl butyral, polyvinyl formal, polysulfone, polyacrylamide, polyamide, chlorinated rubber, Polyvinyl anthracene, polyvinyl pyrene and the like are used.

These resins may be used alone or in combination of two or more. Coating method is spin coater, applicator,
Spray coater, bar coater, immersion coater, doctor blade, roller coater, curtain coater,
It is performed using a bead coater or the like.
It is preferable to apply the coating so as to have a thickness of 50 μm, preferably 10 to 30 μm.

In addition to these layers, an undercoat layer having a barrier function and an adhesive function may be provided between the conductive substrate and the photosensitive layer.

As an undercoat layer, nylon 6, nylon 66,
Alcohol-soluble polyamides such as nylon 11, nylon 610, copolymerized nylon and alkoxymethylated nylon, casein, polyvinyl alcohol, nitrocellulose, ethylene-acrylic acid copolymer, gelatin, polyurethane, polyvinyl butyral, and metal oxides such as aluminum oxide are used. Can be It is also effective to include conductive particles such as metal oxide and carbon black in the resin.

The thickness of the undercoat layer is 0.05 to 10 μm, preferably
About 0.1 to 1 μm is appropriate.

Further, the electrophotographic photoreceptor of the present invention, on a conductive substrate,
It is desirable that the undercoat layer, the charge generation layer, and the charge transfer layer are stacked in this order, but the undercoat layer, the charge transfer layer, the charge transfer layer that is stacked in this order, and the charge generation material on the undercoat layer The charge transfer material may be dispersedly coated with a suitable resin. Further, these undercoat layers can be omitted as necessary.

Further, the electrophotographic photoreceptor of the present invention has an absorption peak at a wavelength near 800 nm as shown in the spectral sensitivity characteristics of FIG.
It is suitable not only for use in copying machines and printers as an electrophotographic photosensitive member, but also as an absorbing material for solar cells, photoelectric conversion elements and optical disks.

Hereinafter, the present invention will be described specifically, but the present invention is not limited to the following examples unless it exceeds the gist.

(Example) An example of the present invention will be described. In the examples, the division is
Indicates parts by weight.

Synthesis Example 1 After 20.4 parts of o-phthalodinitrile and 7.6 parts of titanium tetrachloride were heated and reacted in 50 parts of quinoline at 200 ° C. for 2 hours, the solvent was removed by steam distillation, followed by a 2% aqueous hydrochloric acid solution, followed by 2% aqueous hydroxide. The product was purified with an aqueous sodium solution, washed with methanol and N, N-dimethylformamide, and then dried to obtain 21.3 parts of titanyl phthalocyanine.

Synthesis Example 2 Aminoiminoisoindolenine (14.5 parts) was heated in 50 parts of quinoline at 200 for 2 hours, and after the reaction, the solvent was removed by steam distillation, followed by purification with a 2% aqueous hydrochloric acid solution and subsequently with a 2% aqueous sodium hydroxide solution. Thereafter, the resultant was sufficiently washed with methanol and N, N-dimethylformamide, and dried to obtain 8.8 parts of a metal-free phthalocyanine.

Synthesis Example 3 20 parts of o-naphthalodinitrile were mixed with 50 parts of quinoline in 20 parts.
After heating at 0 ° C. for 4 hours, the mixture was purified with a 2% hydrochloric acid aqueous solution.
After washing with methanol and N, N-dimethylformamide, it was dried to obtain 15 parts of a metal-free naphthalocyanine.

Synthesis Example 4 10 parts of 4-nitro-1,2-phthalonitrile and 20 parts of 1,8-diazabicyclo [5.4.0] -7-undecene in 100 parts of 2,4-dichlorotoluene at 70 ° C. for 6 hours. After the heating reaction, the precipitated crystals were filtered, washed with methanol and benzene, and then dried to obtain 11.5 parts of metal-free methoxyphthalocyanine.

Synthesis Example 5 Metal-free methoxyphthalocyanine obtained in Synthesis Example 4 18.4
Parts, 10 parts of titanium tetrachloride in 200 parts of quinoline at 200 ° C.
After the reaction with heating for a period of time, the solvent is removed by steam distillation, and the mixture is purified with a 2% aqueous hydrochloric acid solution and subsequently with a 2% aqueous sodium hydroxide solution, washed with methanol and N, N-dimethylformamide, and dried, and 17.4 parts of titanylmethoxyphthalocyanine is added. Obtained.

Example 1 1 part of titanyl phthalocyanine obtained in Synthesis Example 1 and 0.05 part of metal-free phthalocyanine obtained in Synthesis Example 2 were gradually dissolved in 30 parts of 98% sulfuric acid at 5 ° C., and the mixture was stirred for about 1 hour.
Stir while keeping the temperature below 5 ° C. Subsequently, the sulfuric acid solution was slowly poured into 500 parts of ice water with high-speed stirring,
The precipitated crystals are filtered. The crystals are washed with distilled water until no acid remains, to obtain a wet cake. The cake (assuming that the content of phthalocyanine contained is 1 part) is stirred in 100 parts of tetrahydrofuran (THF) for about 1 hour, filtered, washed with THF to obtain a titanyl phthalocyanine composition having a pigment content of 0.95 part. A THF dispersion was obtained. After drying partially, the infrared absorption spectrum and the X-ray diffraction image were examined.
As a result, the infrared absorption spectrum was new as shown in FIG. 1, and the X-ray diffraction pattern was as shown in FIG.

Next, 1 part of titanyl phthalocyanine obtained in Synthesis Example 1 is treated in the same manner as in obtaining the titanyl phthalocyanine composition to obtain a wet cake. After filtering the cake once, in 100 parts of methyl ethyl ketone for about 1 hour,
The mixture was stirred at ℃ and filtered to obtain α-type titanyl phthalocyanine containing 0.95 parts of pigment. After drying, the infrared absorption spectrum and the X-ray diffraction image were examined. As a result, the infrared absorption spectrum was as shown in FIG. 2, and the X-ray diffraction pattern was as shown in FIG.

And the titanyl phthalocyanine composition is dry weight
1.2 parts, α-type titanyl phthalocyanine is 0.3% by dry weight
Part, butyral resin (Sekisui Chemical; BX-1) 1 part, THF80
The coating composition was adjusted using an ultrasonic disperser so as to be a part.
This dispersion is mixed with a polyamide resin (manufactured by Toray; CM-8000) for 0.5 part.
0.3μm dry film thickness on μm coated aluminum plate
To form a charge generation layer. As a result of examining the infrared absorption spectrum and the X-ray diffraction image at this time, the results were as shown in FIGS. 3 and 6.

Furthermore, as a charge transfer material, 30 parts of poly-2,3-epoxypropylcarbazole, 100 parts of p-diethylaminobenzaldehyde- (diphenylhydrazone) of the hydrazone compound (b) of the general formula [I], and a polycarbonate resin (Mitsubishi Gas Chemical; Z-200) 50 parts, 2,4-bis-
(N-octylthio) -6- (4-hydroxy-3,5-
A solution dissolved in 5 parts of di-t-butylanilino-1,3,5-triazine and 600 parts of a toluene / THF (1/1) mixed solution is applied to a dry film thickness of 15 μm to form a charge transfer layer. did.

Thus, an electrophotographic photosensitive member having a laminated photosensitive layer was obtained. The half-life exposure (E1 / 2) of this photoreceptor was measured by an electrostatic copying paper tester (Kawaguchi Electric Works; EPA-8100). That is, it was charged by a corona discharge of -5 kv in a dark place, and then exposed with white light having an illuminance of 5 lux, and an exposure amount E1 / 2 (lux · sec) required for attenuating the surface potential by half was obtained.

Example 2 o-Methyl-dibenzylaminobenzaldehyde- (diphenylhydrazone) of a hydrazone compound (g) instead of the hydrazone compound (b) used in Example 1 above
A photoreceptor was manufactured in the same manner as in Example 1 except for using.

Example 3 The 1,1-bis- (p-diethylaminophenyl) -4,4-diphenyl-1,3-butadiene of the butadiene compound (n) was used in place of the hydrazone compound (b) used in Example 1. A photoreceptor was manufactured in the same manner as in Example 1 except for the above.

Example 4 Synthesis Example 4 in place of the metal-free phthalocyanine of Example 1
The titanyl phthalocyanine composition was obtained using 0.12 part of the metal-free methoxyphthalocyanine obtained in the above. A photoreceptor was produced in the same manner as in Example 1 as a charge transfer layer on the charge generation layer using the same.

Example 5 Synthesis Example 3 in place of the metal-free phthalocyanine of Example 1
The titanyl phthalocyanine composition was obtained using 0.05 parts of the metal-free naphthalocyanine obtained in the above. On the charge generation layer using the same, as a charge transfer layer, 40 parts of poly-2,3-epoxypropylcarbazole and 80 parts of o-methyl-p-dibenzylaminobenzaldehyde- (diphenylhydrazone) of a hydrazone compound (g), 1,1 of butadiene compound (n)
-Bis- (p-diethylaminophenyl) -4,4-diphenyl-1,3-butadiene 40 parts, polycarbonate resin 4
0 parts, 2,4-bis- (n-octylthio) -6- (4-hydroxy-3,5-di-t-butylanilino-1,3,5-triazine 3 parts, 2-hydroxy-4-methoxybenzophenone A photoconductor was prepared in the same manner as in Example 1, except that a solution dissolved in 2 parts and 600 parts of a toluene / THF (1/1) mixed solution was used.

Example 6 Synthesis Example 5 in place of the metal-free phthalocyanine of Example 1
Using 0.09 part of the titanyl methoxy phthalocyanine obtained in the above, a titanyl phthalocyanine composition was obtained. As a charge transfer layer on the charge generation layer using the same, 75 parts of the poly-2,3-epoxypropyl carbazole used in Example 5 above,
A photoconductor was prepared in the same manner as in Example 5, except that a solution prepared by using 25 parts of a polycarbonate resin was used.

Comparative Example 1 100 parts of a hydrazone compound (b), 100 parts of a polycarbonate resin and toluene were placed on the charge generation layer used in Example 1.
A photoreceptor coated with a solution consisting of 600 parts of a / THF (1/1) mixture was prepared.

Comparative Example 2 In Comparative Example 1, a photoconductor was prepared using a butadiene compound (n) instead of the hydrazone compound (b).

Comparative Example 3 In Comparative Example 1, a photoconductor was prepared by applying a solution composed of 100 parts of poly-2,3-epoxypropylcarbazole and 400 parts of dichloromethane on the charge generation layer.

Comparative Example 4 A photoconductor was prepared in the same manner as in Comparative Example 1, except that the titanyl phthalocyanine composition was used as the charge generation layer.

Comparative Example 5 A photoconductor was prepared in the same manner as in Comparative Example 1, except that α-titanyl phthalocyanine was used as the charge generation layer.

Table 1 shows the results of evaluating various characteristics of the electrophotographic photosensitive members manufactured in Examples 1 to 6 and Comparative Examples 1 to 5 described above.

(Effects of the Invention) As is clear from Table 1, the chargeability is increased and the dark decay rate is improved as compared with the case of using the titanyl phthalocyanine composition or the α-type titanyl phthalocyanine alone component.

Further, the titanyl phthalocyanine composition of the present invention and α
By making the component mixed with the type titanyl phthalocyanine, it becomes a crystal which is stable for a longer period and is stable to the solvent. Since a paint is obtained, it is easy to form a homogeneous film, which is important in the production of a photoconductor.

In addition, when poly-2,3-epoxypropylcarbazole, hydrazone compound, or butadiene compound is used alone as a charge transfer material, it shows disadvantages such as a large residual potential remaining and a large dark decay. Although not desirable, poly-2,3-epoxypropylcarbazole and a hydrazone compound or a butadiene compound, or a combination of poly-2,3-epoxypropylcarbazole and a hydrazone compound and a butadiene compound,
Since the binding property is increased and the photoconductive material can be used while keeping the concentration thereof high, an electrophotographic photosensitive member having excellent electric characteristics can be obtained.

The obtained electrophotographic photosensitive member has high photosensitivity to a laser wavelength range, and is particularly effective as a high-speed, high-quality photosensitive member for a printer.

[Brief description of the drawings]

FIG. 1 is an infrared absorption spectrum of the titanyl phthalocyanine composition of the present invention, FIG. 2 is an infrared absorption spectrum of α-type titanyl phthalocyanine, and FIG. 3 is a diagram of the titanyl phthalocyanine composition and α-type titanyl phthalocyanine of the present invention. FIG. 4 shows an X-ray diffraction diagram of the titanyl phthalocyanine composition, FIG. 5 shows an X-ray diffraction diagram of the α-type titanyl phthalocyanine composition, and FIG. 6 shows a titanyl phthalocyanine composition in a coating film state. X-ray diffraction diagram by a mixed component of α-type titanyl phthalocyanine,
FIG. 7 is a spectral characteristic diagram of the electrophotographic photoreceptor of the present invention obtained by the example.

Claims (4)

(57) [Claims] 1. An electrophotographic photoreceptor containing a charge generating material and a charge transfer material, wherein the charge generating material comprises: (a) a metal-free phthalocyanine nitrogen isoform, a metal phthalocyanine nitrogen isoform, metal-free phthalocyanine, metal phthalocyanine, metal-free Naphthalocyanine or metal naphthalocyanine (however, metal-free phthalocyanine nitrogen isoform, metal phthalocyanine nitrogen isoform, metal-free phthalocyanine, metal phthalocyanine may have a substituent on the benzene nucleus. Phthalocyanine may have a substituent in the naphthyl nucleus), and a total of 50 parts by weight or less of the composition crystal containing 100 parts by weight of titanyl phthalocyanine. The absorption spectrum shows that the absorption wave number (cm ^-1 ) is 1609 ±
2, 1480 ± 2, 1458 ± 2, 1365 ± 2, 1332 ± 2, 1165 ±
2,1072 ± 2, 961 ± 2, 876 ± 2, 730 ± 2, a composition crystal having a strong absorption characteristic, and in the X-ray diffraction spectrum using CuK as a source, the Bragg angle (2
θ ± 0.2 °) is 9.7 °, 11.7 °, 13.3 °, 15.0 °, 24.1 °
And a titanyl phthalocyanine composition crystal having a strong diffraction peak at 27.3 degrees, and (b) its infrared absorption spectrum, 1611 ± 2, 1476 ± 2, 1463 ± 2, 1430 ± 2, 13
35 ± 2, 1160 ± 2, 1068 ± 2, 971 ± 2, 965 ± 2, 940
A crystal having characteristic absorptions at ± 2, 879 ± 2, 839 ± 2, and 773 ± 2, and a Bragg angle (2θ ± 0.2 degrees) of 7.5 in an X-ray diffraction spectrum using CuK as a source.
Degrees, 10.2 degrees, 12.6 degrees, 16.3 degrees, 18.3 degrees, 22.4 degrees, 24.3 degrees
And an α-type titanyl phthalocyanine crystal having strong diffraction peaks at 25.4 ° and 28.6 ° as active ingredients. 2. The charge-transporting material is poly-2,3-epoxypropylcarbazole represented by the following structural formula [A]: And a hydrazone compound represented by the following general formula [I] (Wherein, R ¹ may form a carbazono group together with a hydrogen atom, a substituted or unsubstituted alkyl group, or an alkoxyl group, a halogen atom, a substituted or unsubstituted amino group, a morphforno group, a piperidino group or a phenyl group. , R ² is a hydrogen atom, a substituted or unsubstituted alkyl group,
It indicates an alkoxyl group or an aralkyloxy group,, R ³
And R ⁴ may form a hydrogen atom, a substituted or unsubstituted alkyl group, an aryl group, an aralkyl group, or a ring such as a pyridyl group, a pyrrhodino group, or a carbazono group. )
Claim 1 characterized by the following:
Item. 3. A charge-transfer material comprising a poly-2,3-epoxypropylcarbazole represented by the structural formula [A] and a butadiene compound represented by the following general formula [II]: 2. The electrophotographic photoreceptor according to claim 1, wherein R ^{5 to} R ⁸ represent an alkyl group, and may be the same or different from each other. 4. A charge-transfer material comprising a poly-2,3-epoxypropylcarbazole represented by the structural formula [A], a hydrazone compound represented by the general formula [I], and a hydrazone compound represented by the general formula [II]. 2. The electrophotographic photoreceptor according to claim 1, wherein the butadiene compound represented by the formula (1) is used as an active ingredient.