JPH03231971A - New hydrazone compound - Google Patents

Abstract

NEW MATERIAL:A compound of formula I [R<1> is (substituted) phenyl or (substituted) naphthyl; R<2> and R<3> are each H or 1-4C alkyl, except that R<1> is (substituted) phenyl and also R<2> is H]. EXAMPLE:4-Diphenylamino-2-methylbenzaldehyde-1,1-diphenylhydrazone. USE:A charge transfer material in electrophotographic photosensitizers with a system using both charge-generating material and charge transfer material. PREPARATION:An iodide of formula II and a secondary amine compound of formula III are dissolved in an organic solvent such as nitrobenzene, and e.g. potassium carbonate as a dehydrohalogenating agent and copper powder as a catalyst are added to the system, which is then reacted under reflux while stirring, thus obtaining a tertiary amine compound of formula IV. This compound is dissolved in an organic solvent such as chloroform, and the resulting system is reacted by dripping phosphorus oxychloride in the presence of DMF into an aldehyde compound of formula V, which is then reacted with 1,1- diphenylhydrazine hydrochloride under heating, thus obtaining the objective compound of the formula I.

Description

Detailed Description of the Invention (Field of Application of Industry-1-) The present invention relates to a novel hydrazone compound. More specifically, the present invention relates to a novel hydrazone compound that effectively functions as a charge transport substance in an electrophotographic photoreceptor using a charge generation substance and a charge transport substance.

(Prior Art) In recent years, electrophotographic photoreceptors have been used not only in the field of electrophotographic copying machines, but also in laser printers powered by 1ie-Ne lasers, semiconductor laser printers powered by semiconductor lasers, and light emitting diodes. Applications to light-emitting diode printers, etc., which use input signals, are being considered.

Electrophotographic photoreceptors used in electrophotographic copying machines have conventionally been made of inorganic photoconductive materials such as selenium, tellurium, cadmium sulfide, and zinc oxide that are sensitive to wavelength light in the visible light range (370 to 720 nm). (feeling like you have a self) and set up a layer (
However, since these substances are hazardous substances, they pose problems in terms of safety and health during manufacturing. In recent years, to compensate for this, electrophotographic photoreceptors using various organic substances have been proposed and are beginning to be put into practical use.

An organic photoreceptor made of such an organic photoconductive substance uses, as a charge generation layer, a resin dispersion layer in which a phthalocyanine or azo compound, which is known as a charge generation substance, is dispersed in a resin on a conductive substrate. Laminated negatively charged photoreceptors, which are formed by coating the second layer with a charge transport layer, have become mainstream. Furthermore, in order to obtain an excellent photoreceptor, the proportion of this transport layer is particularly important.

In many cases, the compounds used in the charge transport layer are low-molecular organic compounds and do not have film-forming ability. Therefore, a film must be formed using a polymer binder such as polyester resin or polycarbonate resin. In order to rapidly transport charge carriers generated in the charge generation layer, the charge transport layer needs to be uniform.

Here, the solubility of the charge transport material in the solvent that dissolves the binder becomes a problem. A substance with low solubility cannot increase the concentration of the charge transport substance in the binder, resulting in a decrease in charge carrier transport ability and poor affinity with the binder resin, which is why it is difficult to use electrophotography. It is not possible to obtain products with good characteristics.

Hitherto, as a charge transport substance, hydrazone compounds have been disclosed, for example, in JP-A-51-59,143 and JP-A-57-1.
1. Compounds disclosed in JP-A-58-199.353 and the like are known. However, these conventional charge transport materials do not necessarily have a sufficiently high solubility and also have poor affinity with binder resins, so the electrophotographic properties such as sensitivity are not always satisfied. It is.

(Problems to be Solved by the Invention) Therefore, an object of the present invention is to provide a novel hydrazone compound, particularly a novel hydrazone compound that effectively functions as a transport substance in an electrophotographic photoreceptor using a charge generating substance and a charge transport substance. The objective is to provide compounds.

(Means for Solving the Problems) These objectives are based on the following general formula [wherein R1 is a phenyl group, a naphthyl group, or a phenyl group or a naphthyl group substituted with an alkyl group having 1 to 4 carbon atoms] R2 is a hydrogen atom or has 1 to 4 carbon atoms
an alkyl group, and R3 is a hydrogen atom or has 1 to 1 carbon atoms.
This is achieved by a novel hydrazone compound represented by 4, which is an alkyl group (excluding compounds in which R1 is a substituted or unsubstituted phenyl group and R2 is a hydrogen atom).

(Function) The hydrazone compound according to the present invention is a compound represented by the above general formula I, where R1 is a phenyl group, a naphthyl group, or a phenyl group or a naphthyl group substituted with an alkyl group having 1 to 4 carbon atoms. , preferably a phenyl group or a naphthyl group, and R3 is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, preferably 1 to 2 carbon atoms (provided that R1 is a substituted or unsubstituted phenyl group and R2 is a hydrogen atom) (excluding compounds).

Examples of such hydrazone compounds include the following.

(CT-1,) (CT-2) (CT-3) (CT-4) (CT-5) (CT-6) CI+3 (CT-7) (CT-8) (CT-9) (CT-10) H3 (CT-11) 113 (CT-12) 0 (CT-14) ・A talented person expressed in the general formula■ The drazine compound is example For example, It can be produced by the following reaction route.

・An iodide represented by the general formula ■ t, / (wherein 2 is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms), and a shipper ■ 171・' (however, 5 , where 1 is a phenyl group, a naphthyl group, or a phenyl group substituted with an alkyl group having 1 to 4 carbon atoms, < is a naphthyl group, and R3 is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. ) is dissolved in an i′J-organic solvent such as nitrobenzene or 0-dichlorobenzene, and a secondary amine compound represented by By adding alkali carbonate and copper powder as a catalyst, and reacting by refluxing under stirring, the general formula (excluding compounds in which R2 is a phenyl group and R2 is a hydrogen atom) are obtained.

The obtained tertiary amine compound represented by general 2) is dissolved in an organic solvent such as chloroform, and N,
By dropping phosphorus oxychloride in the presence of N-dimethylpolamide and reacting by heating, the general 2 unsubstituted phenyl group and R
(excluding compounds in which 2 is a hydrogen atom) are obtained.

The obtained aldehyde compound represented by general formula V and hydrochloric acid 1. ]-Diphenylhydrazine is added to 11 alcoholic solvents such as ethanol, methanol, butanol,
By heating and reacting, a hydrazone compound represented by general formula I is obtained.

The novel hydrazone compound according to the present invention functions extremely effectively as a charge transport agent in an electrophotographic photoreceptor.

A photoreceptor using the hydrazone compound of the present invention can be formed by laminating a charge generating layer and a charge transporting layer by coating a conductive support in the form of a thin film. In this case, since the hydrazone compound in the present invention does not have film-forming ability by itself, it can be used in combination with a binder and dissolved in a white organic solvent to prepare a photoreceptor. The resin used as a binder at that time is, for example, polyester resin,
Polyamide resin, acrylic resin, polyvinyl chloride resin,
Examples include FJNol resin, polycarbonate resin, polystyrene resin, and polysulfone resin, with polycarbonate being preferred. Poly-N-vinylcarbazole, which itself has charge transporting ability, can also be used as a binder. The organic solvents used in this case include alcohols such as methanol, ethanol, and isopropanol, ketones such as acetone, methyl ethyl ketone, and cyclohexanone, N,N-dimethylpolamide,
Amides such as N, N dimethylacetamide, sulfoxides such as dimethyl sulfoxide, ethers such as tetrahydrofuran, dioxane, ethylene glycol methyl ether, methyl acetate, convex
1 acid J, esters such as del, aliphatic halogenated hydrocarbons such as chloroform, methylene chloride, dichloroethylene, dichloroethane, carbon tetrachloride, trichloroethylene, or benzene, l-luene, xylonone, Examples include aromatic compounds such as monochlorobenzene, monochlorobenzene, and dichlorobenzene, with dichloroethane being preferred. The amount of the hydrazone compound to be used is preferably 10 to 30% by weight of TiT, particularly 50 to 200% by weight, based on the resin used as the binder.

If the amount of the charge transport material is less than 10% by weight, the charge transporting ability will decrease, and if it exceeds 300% by weight, the mechanical strength of the photoreceptor will be poor, which is not preferred in practice.

The thickness of the charge transport layer is 5 to 50 μm, particularly 10 to 25 μm.
tyn is preferred.

The present inventors have discovered a charge transport substance that is highly soluble in the solvent that dissolves the binder resin, which has the effect of increasing the affinity with the binder resin, thereby causing charge transport. We thought that it would be able to function effectively as a drug, and we conducted extensive studies. Consequently, in fact, the hydrazone compound according to the invention is
For example, the hydrazone compound C"r-1 of the present invention, which has high solubility in the organic solvent, and JP-A-57-11,35
Comparing the solubility of the hydrazone compound (abbreviated as TPAH) disclosed in No. 0 in dichloroethane, which is a solvent capable of dissolving the polycarbonate resin suitably used as a binder resin, the former dissolves at 64.1% by weight in dichloroethane. In contrast, the latter dissolves only 13.6% by weight. After all, this is the difference in the electrophotographic properties (see Reference Example 9 and Comparative Example 2), which will be described later.

The charge transporting substance of the present invention can be used particularly in a laminated type electrophotographic photoreceptor consisting of a charge generation layer and a charge transporting layer. Phenyl group, naphthyl group or carbon number 1 to 5 whose nucleus is not substituted
a phenyl group substituted with an alkyl group, preferably a substituted or unsubstituted phenyl group), and a charge transport layer containing the novel hydrazone compound of the present invention. By providing the layer on the conductive support 1-, it functions extremely effectively as an electrophotographic photoreceptor.

7 The charge-generating substance used in the present invention is represented by the above-mentioned -. Funato (2). Specific examples of the zinc phthalocyanine represented by the above-mentioned general formula include the following. In the following examples, fluorine atoms are 1.4, 5° 8.9, 12.13 and 1-6 of the phthalocyanine nucleus represented by formula (■).
A total of eight compounds have been introduced. Also, zinc phthalocyanine [F8 octafluoro-off zinc phthalocyanine [I? 8 octafluoro-off zinc phthalonanine [I゛8] (PhS)s ZnPc octafluoro -octakis(p-)lylthio)zinc phthalocyanine [Fs (p-MePhS) s ZnP
c], octafluoro-octakis(2,4-xylylthio)zinc phthalocyanine 0's (2,4-MePhS) s ZnPe
, octafluoro-octakis (2,3-xylylthio) zinc phthalocyanine [Pa (2,3-MePhS) a ZnPc1, octafluoro-octakis (0-ethylphenylthio)
Zinc phthalocyanine [Fa (o-EtPhS) 8 ZnPc co
, octafluoro-octakis (p-ethylphenylthio) zinc phthalocyanine [Fa (p-EtPhS) s ZnPc , octafluoro-octakis (0-isopropylphenylthio) zinc phthalocyanine [Ps (o-IPrPhS) s ZnPc ,
Octafluoro-octakis (p-isopropylphenylthio) zinc phthalocyanine [Fe (p-IPrPhS) s ZnPc1,9 Octafluoro-octakis (0-butylphenylthio) zinc phthalocyanine [Ps (o-BuPhS) s ZnPc1, octafluoro- Octakis (m-butylphenylthio) zinc phthalocyanine [FB (m-BuPhS) B ZnPc], octafluoro-octakis (p-butylphenylthio) zinc phthalocyanine [Ps (p-BuPhS) e ZnPc1
, octafluoro-octakis(p-tert-butylphenylthio)zinc phthalocyanine [:Pa (p-
BuPhS) s ZnPc], octafluoro-octakis(naphthylthio)zinc phthalocyanine [Fs (NPhS) s ZnPe1, and the like.

The charge-generating substance can be used by being dispersed in a binder dissolved or dispersed in an organic solvent in preparing the photoreceptor, and then applied to the conductive support -1-.

Examples of the resin used as a binder in this case include polyvinyl butyral resin, silicone resin, acrylic resin, epoxy resin, polyester resin,
Examples include polyamide resin, phenol resin, alkyd resin, urethane resin, and polycarbonate resin.

Organic solvents used in this case include aromatic hydrocarbons such as benzene and toluene, cyclic ethers such as tetrahydrofuran and dioxane, hydrocarbons such as chloroform, dichloromethane, and dichloroethane, ketones such as acetone, methyl ethyl ketone, and cyclohexanone, and ethyl acetate. and cellosolves such as methyl cellosolve. These may be used in combination depending on the case. Alternatively, the solvent for dissolving or dispersing the binder and the solvent for dispersing the phthalocyanine may be different, and then the two may be mixed. The ratio of the phthalocyanine compound to the resin used as a binder is 10 to 300% by weight, preferably 50 to 200% by weight.
Good to use.

The ratio of the phthalocyanine compound to the organic solvent is preferably 10.5 to 50% by weight, preferably 2 to 20% by weight.

If the amount of the charge generating material is less than 10% by weight, the charge generating ability will be small, and if it exceeds 300% by weight, there will be problems such as poor adhesion. The thickness of the charge generation layer is preferably 0.1 to 10 μm, particularly 0.62 to 2 μm.

In the present invention, the conductive support is, for example, aluminum,
A polymer film or the like on which a metal such as copper or nickel, aluminum oxide, indium oxide, or tin oxide is vapor-deposited or laminated can be used. As the coating method, known methods such as dip coating, spray coating, spinner coating, blade coating, roller coating, wire bar coating, etc. can be used.

(Example) Next, the present invention will be explained in more detail by giving examples.

Example 1 (1) Synthesis of N,N-diphenyl-3-methylphenyl 2 amine 18.6 g of diphenylamine and 24.2 g of 3-iodotoluene were dissolved in 100 ml of nitrobenzene, and 15.3 g of potassium carbonate and copper powder were dissolved therein. 0.6 g was added and refluxed for 24 hours with stirring. After the reaction, nitrobenzene was distilled off by steam distillation.

The residue was extracted with benzene, washed with filtered water, and concentrated to obtain crude crystals. Recrystallize and purify with acetone to obtain N,N-
22.0 g of diphenyl-methylphenylamine was obtained.

Yield 76.5%, mp, 68-69°C0 Elemental analysis value C (%) H (%) N (%) Theoretical value 87.98 6.62 5.40 Actual value
88. 01 6. 68 5. 31(2)4-(
Synthesis of N,N-dimethylamino)-2-methylbenzaldehyde 9 g of N,N-diphenyl-3-methylphenylamine was dissolved in 50 g of dimethylformamide, and the mixture was stirred and cooled with water for 2 hours.
5.3 g of phosphorus oxychloride was added dropwise over 0 minutes. After stirring at room temperature for 1 hour, the mixture was stirred at 80°C for 5 hours. The reaction solution was poured into 250 ml of water, neutralized with sodium hydroxide, extracted with chloroform, washed with water, and concentrated to obtain crude crystals. After recrystallization and purification with ethanol, 4-
7.1 g of (N,N-dimethylamino)-2-methylbenzaldehyde was obtained. Yield 71.2%, mp, 157~
158℃.

・Elemental analysis value C (%) H (%) N (%) 0 (%) Theoretical value 8
3.58 5.97 4.88 5.57 Actual value
83.62 5.95 4.91 5.52 (3)
4-diphenylamino-2-methylbenzaldehyde
Synthesis of 1,1-diphenylhydrazone (CT-1) 3 g of 4-(N,N-diphenylamino)-2-methylbenzaldehyde and 2.3 g of 1,1-diphenylhydrazine hydrochloride were added to 60 ml of ethanol, and the mixture was heated at room temperature for 1 hour. After stirring, the mixture was stirred under reflux for 3 hours.

The reaction solution was concentrated and cooled, and the formed crystals were collected by filtration and purified by recrystallization with ethyl acetate-ethanol to obtain 3.5 g of 4-diphenylamino-2-methylbenzaldehyde-1,1-diphenylhydrazone. Ta. Yield 73.3%, mp, 146-147°C.

・Element bone i value C (%) H (%) N (%) Theoretical value 84
．． 72 6.01 9. 27 actual d (value 84.8
0 6.00 9.20・Infrared absorption spectrum (FT-
IR) The infrared absorption spectrum of this substance is shown in Figure 1.

Example 2 (1) Synthesis of N,N-diphenyl-α-naphthylamine 17.6 g of diphenylamine and 25.4 g of 1-iodonaphthalene were dissolved in 100 ml of nitrobenzene,
Add 13.8g of potassium carbonate and 0.5g of copper powder to this,
The mixture was refluxed for 12 hours with stirring, and after the reaction, nitrobenzene was distilled off by steam distillation. The residue was extracted with benzene,
After filtration, it was washed with water and concentrated to obtain crude crystals. Purified by recrystallization with acetone to obtain N,N-diphenyl-α-naphthylamine 22.2
I got g. Yield 75.3%, mp.

139-141°C.

・Elemental analysis value C (%) Theoretical value 89.44 Actual value 89. 53 (2) Synthesis of 4-(N-naphthylnobenzaldehyde) 9 g of N,N-diphenyl-α-naphthylamine was dissolved in 50 g of dimethylformamide, and 6 g of phosphorus oxychloride was added dropwise over 20 minutes while stirring and cooling with water.

After stirring at room temperature for 1 hour, the mixture was stirred at 80°C for 5 hours.

The reaction solution was poured into 250 ml of water, neutralized with sodium hydroxide, extracted with chloroform, washed with water, and concentrated to obtain crude crystals. Perform recrystallization purification using ethanol to obtain 4-(N-
Naphthyl-N-phenyl)aminobenzaldehyde6.
9g was obtained. Yield 70°0%, mp, 115-116°
C0 6 H (%) N (%) 5, 81 4. 74 5, 85 4. 62 N-Phenyl) Amide Elemental analysis value C (%) H (%) N (%) 0 (%) Theoretical value
85.41 5.31 4.33 4.95 Actual value 85.50 5.36 4.25 4.89 (3
)l (N-naphthyl-N-phenyl)aminobenzaldehyde-14,1-diphenylhydrazone (CT-1
Synthesis of 2) 3.0 g of 4-(N-naphthyl-N-phenyl)aminobenzaldehyde and 2.0 g of 1,1-diphenylhydrazine hydrochloride were added to 60 ml of ethanol, stirred at room temperature for 1 hour, and then stirred under reflux for 3 hours.

The reaction solution was concentrated and cooled, and the formed crystals were collected by filtration and purified by recrystallization with ethyl acetate-ethanol to obtain 4-(N-naphthyl-N-phenyl)aminobenzaldehyde-1,
3.2 g of 1-diphenylhydrazone was obtained. Yield 71.
4%, mp, 95-96°C.

7 ・Elemental analysis value C (%) H (%) N (%) Theoretical value 8
5.85 5. 57 8. 58 Actual value 85.8
9 5. 62 8.49・Infrared absorption spectrum (FT
-IR) The infrared absorption spectrum of this substance is shown in Figure 2.

Example 3 (1) Synthesis of N-(3-methylphenyl)-bis(,/1methylphenyl)amine 21.7 g of bis(4-methylphenyl)amine and 3
-Iodotoluene 24.2g- was dissolved in 100ml of nitrobenzene, 15.3g of potassium carbonate and 0.6g of copper powder were added thereto, and the mixture was refluxed for 24 hours with stirring. After the reaction, 2L lobenzene was extracted by steam distillation. Distilled away. The residue was extracted with benzene, washed with filtered condensed water, and concentrated to obtain crude crystals. The product was purified by recrystallization using acetone to obtain 23.1 g of N-(3-methylphenyl)-bis(4-methylphenyl)amine. Yield 73.0%.

(2) 4-bis(p-methylphenyl)amino 8 Synthesis of 2-methylbenzaldehyde 11-(3--Methylphenyl)-bis(4-methylphenyl)amine 9.5g was dissolved in dimethylformamide 50g.
Phosphorus oxychloride was dissolved in
．． 3 g was added dropwise. After stirring at room temperature for 1 hour, the mixture was stirred at 80°C for 5 hours. The reaction solution was poured into 250 ml of water, neutralized with sodium hydroxide, extracted with chloroform, washed with water, and concentrated to obtain crude crystals.

4-bis(p-
7.4 g of methylphenyl)amino-2-methylbenzaldehyde was obtained. Yield 71.0%.

(3) 4-bis(p-methylphenyl)amino 2-methylbenzaldehyde-1,1-diphenylhydrazone (
Synthesis of CT-4) 3.3 g of 4-bis(p-methylphenyl)amino-2methylbenzaldehyde and 2.3 g of 1,1-diphenylhydrazine hydrochloride were added to 60 ml of ethanol, stirred at room temperature for 1 hour, and then refluxed for 3 hours. Stirred. The reaction solution was concentrated and cooled, and the formed crystals were collected by filtration and purified twice by recrystallization with ethyl acetate-ethanol to obtain 4-bis(p-methylphenyl)amino-2-methylbenzaldehyde-1,1 diphenylhydrazone. 3.6g was obtained. Yield 7].

4%, mpl, 13-114°C.

- Elemental analysis value C (%) H (%) Theoretical value 84.79 6.49 Actual chain 84.71 6.50 Reference example 1. Synthesis of Fs (PhS) a ZnPc/starting material 3.4. 5. 6 te 1
Herafluorophthalonitrile19. 6 g (98 mmol), 21.6 g (196 mmol) of thiophenol, 17.1 g (294 mmol) of potassium fluoride (KF) and ml of acetonitrile were added, and the mixture was heated at 50°C for 1 ml.
It was kept under stirring for 2 hours. It was then cooled to room temperature, the yellow solid obtained was filtered, and the resulting cake was purified by washing with methanol and then with warm water, 3,6-difluoro-4,5
-34.5 g of bisphenylthiophthalonitrile (vs. ON (%) 8, 72 8, 78 3.4,5.6-titrafluorophthalonitrile yield 9
2.5 mol%) was obtained.

Synthesis of FB (Phi) B ZnPc 100ml 4
A Tulo flask was charged with 10 g (26.2 mmol) of 3,6-difluoro-4.5-bisphenylthiophthalonitrile, 3.14 g (9.8 mmol) of zinc iodide, and 50 mt of benzonitrile. .75℃
The mixture was kept under stirring for 6 hours. After cooling, the resulting green solid was filtered and then washed with Soxhlet in the order of methanol, benzene, and acetone, and Ps (
Phi)s ZnPc3 2. 1 g (vs. 3,6
-difluoro-4.

5-bisphenylthiophthalonitrile yield: 79.

4 mol%) was obtained.

Sanka Example 2 Pa (PhS)a ZnPcO. 30g, butyral resin (S-LEC BM-2. manufactured by Sekisui Chemical Co., Ltd.)
0.

30 g., 4.0 ml of nclohexane, and methyl edyl ketone 4. Oml and paint shaker disperser 2
Spread out time. This dispersion was applied to an aluminum plate I- using a bar coater 1 and dried with hot air at 60° C. for 2 hours to form a charge generation layer. At this time, the film thickness is 0,
5 μn).

Next, the hydrazone compound [C1'-1
] 1.0g and polycarbonate resin (Panrai hL
1250 (manufactured by Teijin Kasei Ltd.)]-, a solution of Og mixed in 10 g of dichloroethane was coated on an aluminum substrate using a bar coater, and then dried with hot air at 60°C for 2 hours and then dried at 100°C for 12 hours. A charge transport layer was formed. The film thickness at that time was 1-5 μm.

The electrophotographic photoreceptor thus prepared was tested using an electrostatic charging tester (Jll+-1 Denki Sr-428).
It was negatively charged at 6.0 kV.

After that, it was held in a dark place for 5 seconds, and then exposed to white light (tungsten lamp) at an illumination intensity of 5ρUX for 5 seconds, and the charging characteristics [surface potential (Vo), potential after being held in the dark for 5 seconds (V5), The potential before exposure is changed to 1-/2 by exposure.
Exposure amount required to attenuate (E1/2) (ΩUX
-SCC), 2 residual potential (VR) after exposure for 15 pux'' sec, and monochromatic light spectrally separated by a spectral filter were irradiated, and the half-reduced exposure energy sensitivity (/lJ/cJ) at each wavelength was determined.

The results are shown in Table 1.

Table 1 Reference Examples 3 to 8 Photoreceptors were prepared in the same manner as in Reference Example 2, except that the phthalocyanine and hydrazone compounds shown in Table 2 below were used instead of the phthalocyanine and hydrazone compounds in Reference Example 2, and photoreceptors were prepared in the same manner as in Reference Example 2. r Photographic properties were measured.

The results are shown in Table 2.

3 Comparative Example 1 A photoreceptor was prepared in the same manner as in Reference Example 2 except that the following diethylaminobenzaldehyde and 1-diphenylhydrazone were used instead of the hydrazone compound in Reference Example 2.

The electrophotographic photoreceptor characteristics were measured in the same manner as in Reference Example 2.

The results are shown below.

5 Reference Example 9 Octafluoro-octakis(phenylthio)zinc phthalocyanine and butyral resin (S-LEC BLS-5,
Sekisui Chemical Shigyo Co., Ltd.) and 0.15 g of each were added to a cyclohexanone/methyl ethyl ketone mixed solvent (
Volume ratio 1:1) Put it in a sample tube with 4 ml and disperse it with a paint shaker for 2 hours, then apply the obtained solution to aluminum PET and dry it for 30 minutes at a temperature of 60°C until the dry film thickness is 0. A charge generation layer of .8 μm was prepared. Then, 4-diphenylamino-2-methylbenzaldehyde-1゜1-diphenylhydrazone (C''1-1) obtained in Example 1 and polycarbonate resin (C-1300, manufactured by Teijin Kasei Ltd.) were mixed in a 1:1 ratio.
The resulting solution was applied to the surface of the charge generation layer, and then heated at 100°C for 10 minutes.
Dry for 2 hours under reduced pressure of 0 torr to obtain a dry film thickness of approximately 1
A photoreceptor was prepared by forming a 3 μm charge transport layer.

The photoconductor thus prepared was mounted on a laser beam printer, and the potential charged by corona discharge (Vo) when unexposed, the potential after laser exposure (V), and V, ρ The potential (V') after being subjected to static elimination exposure was measured.

Furthermore, changes in each potential after repeating charging exposure 20,000 times were also measured. The results are shown in Table 3.

Comparative Example 2 In place of the hydrazone compound (C”r-1) in Reference Example 9, the following 4-(N,N-diphenylamino)benzaldehyde-1,1-diphenylhydrazone (TPA
VO1V in the same manner as Reference Example 9 except that H) was used.
ρ and Vr were measured.

The results are shown in Table 3.

Table 7 (Effects of the Invention) The hydrazone compound according to the present invention is a new compound as shown in ``-'' and is extremely effective as a charge transport material in an electrophotographic photoreceptor using a charge generation material and a charge transport material. Furthermore, such an electrophotographic photoreceptor has, for example, a photoreceptor (Reference Example 9) using the charge transport material of Example 1, which has a low potential (Vρ) 8 after exposure as an initial characteristic; Since the initial potential (Vo) is almost the same as that of the photoreceptor using TPAH (Comparative Example 2), the difference (Vo-vρ) is large, and as a result, the contrast of the image is high. Furthermore, a relatively stable potential can be obtained even after repeated exposure 20,000 times. Therefore, even after repeated use 20,000 times, compared to photoconductors using TPAH,
It has excellent stability.

[Brief explanation of drawings]

FIG. 1 is a diagram showing an infrared absorption spectrum of one example of a hydrazone compound according to the present invention, and FIG. 2 is a diagram showing an infrared absorption spectrum of another example of a hydrazone compound.

Claims (1)

[Claims] (1) A novel hydrazone compound represented by the following general formula I. ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (I) [In the formula, R^1 is a phenyl group, a naphthyl group, or a phenyl group or a naphthyl group substituted with an alkyl group having 1 to 4 carbon atoms, R^ 2 is a hydrogen atom or carbon number 1
~4 alkyl group, and R^3 is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms (provided that compounds in which R^1 is a substituted or unsubstituted phenyl group and R^2 is a hydrogen atom) )] (2) In general formula I, R^1
is a phenyl group or a naphthyl group, R^2 is a carbon number of 1 to 4
The hydrazone compound according to claim 1, wherein R^3 is an alkyl group, and R^3 is a hydrogen atom.