JPH0748324A - Terphenyl derivative and electrophotographic photoreceptor using the same - Google Patents

Abstract

PURPOSE:To obtain a new terphenyl derivative extremely useful as a material for providing an electrophotographic photoreceptor having high sensitivity as a photoconductive material and excellent stability of electrical characteristics during repeated use. CONSTITUTION:A compound of formula I (R1 and R2 are H or alkyl which may contain a substituent group; R3 and R4 are phenyl which may contain a substituent group) such as N,N-di(4-methylphenyl)-1,1':3',1'-terphenyl-4'-amine. The compound is obtained by reacting a 4'-iodo-1,1':3',1W'-terphenyl derivative of formula II with a diarylamino compound of formula III in the absence of a solvent or in a solvent such as N,N-dimethhylformamide or sulfolane in the presence of a catalyst such as copper powder or a copper halide and a basic inorganic salt such as an alkali metal carbonate at 150-250 deg.C under heating. The compound is contained as a charge transporting material in a photosensitive layer of an electrophotographic photoreceptor having a sensitive layer on an electrically conductive substrate.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a novel terphenyl derivative useful as a photoconductive material and an electrophotographic photoreceptor containing the compound in a photosensitive layer.

[0002]

2. Description of the Related Art Various photoconductive materials such as poly-N-vinylcarbazole have been proposed as photoconductive materials used in electrophotographic photoreceptors, and research and development have been actively conducted.

Such an organic compound type electrophotographic photoconductor is easier to form a film than an inorganic compound type electrophotographic photoconductor using selenium, cadmium sulfide, zinc oxide or the like, and has extremely high productivity. It has the advantage of being able to provide a high and inexpensive electrophotographic photoreceptor.

However, for example, with respect to photoconductive polymers such as poly-N-vinylcarbazole, the polymer alone has poor coating properties, flexibility, adhesiveness and the like, and in order to improve these drawbacks, it is plastic. Agent, binder resin, etc. are added, but this causes problems such as a decrease in sensitivity and an increase in residual potential.

In recent years, in order to solve the drawbacks and problems of these electrophotographic photoreceptors, the functions of generating electric charges and most of the charge transporting functions of the electrophotographic photoreceptors are carried out by separate substances. A separation type electrophotographic photoreceptor has been proposed. In such a function-separated type electrophotographic photosensitive member, a charge generating material having a charge generating function, or a charge transporting material exhibiting a charge transporting function, each of which has a wide selection range, and in combination thereof, charging characteristics, It is possible to provide a high-performance electrophotographic photosensitive member by controlling electrophotographic characteristics such as charge retention ability in a dark place, sensitivity, repeated stability, and durability.

That is, by selecting an appropriate material for the charge generating material, it is possible to provide an electrophotographic photosensitive member having a photosensitive wavelength characteristic adapted to the spectral wavelength of the light source. Specifically, azo pigments, phthalocyanine pigments, condensed polycyclic pigments, squarylium dyes, azurenium dyes, thiapyrylium dyes, cyanine dyes and the like have been proposed.

Many organic compounds have been proposed as charge transport materials. For example, US Pat.
JP-A-0,730 discloses an electrophotographic photoreceptor using a triphenylamine derivative substituted with an alkyl group, an alkoxy group, a nitro group, a halogen atom or the like. US Pat. No. 3,739,000, US Pat.
Japanese Patent No. 4,000 discloses triarylmethane compounds and diarylmethane compounds substituted with an alkylamino group. JP-A-3-114058 and JP-A-3-127765 disclose triphenylamine compounds substituted with a specific alkyl group.
However, when these arylmethane compounds and triphenylamine compounds are used as charge transport materials for electrophotographic photoconductors, although dark decay is small and chargeability is excellent, residual potential is high and sufficient sensitivity cannot be obtained. However, there are drawbacks such that electrical characteristics change due to repeated use and stable characteristics cannot be obtained.

Further, JP-A-1-280763 and JP-A-2-36156 disclose 4-diphenylamino-1,1'-biphenyl compounds, and JP-A-2-13463 discloses them. , A terphenyl derivative having a substituted amino group is disclosed.
The electrophotographic photosensitive member used as the charge transport material has drawbacks such that sufficient sensitivity cannot be obtained and electric characteristics change due to repeated use so that stable characteristics cannot be obtained.

In addition, it has been proposed to use a photoconductive material such as a hydrazone compound and a styryl compound for an electrophotographic photoreceptor, but it is not satisfactory in terms of sensitivity and stabilization of characteristics upon repeated use.

[0010]

As described above, many organic compounds have been proposed for the charge transport material, but in reality, there are various problems. That is, even in these electrophotographic photoreceptors, those satisfying all the following characteristics required for the electrophotographic photoreceptors such as sensitivity have not always been easily obtained, and further Improvement is required.

(1) It can be charged to an appropriate potential in a dark place. (2) The ability to retain electric charges in a dark place is large. (3) Charges can be rapidly dissipated by light irradiation. (4) An electrophotographic photosensitive member having an appropriate area can be easily manufactured. (5) Repeatability is good. (6) It has durability. (7) It is inexpensive.

The problem to be solved by the present invention is (1)
To provide a novel and useful terphenyl derivative having excellent durability as a photoconductive material, and (2) to overcome the drawbacks of conventional inorganic compound type electrophotographic photoreceptors and to propose organic compounds. An object of the present invention is to provide an electrophotographic photosensitive member which is improved in the drawbacks of the compound-based electrophotographic photosensitive member and has high sensitivity enough to be put to practical use and stability of electric characteristics upon repeated use.

[0013]

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

That is, in order to solve the above problems, the present invention provides (1) general formula (I)

[0015]

[Chemical 2]

(In the formula, R ₁ and R ₂ each independently represent hydrogen or an alkyl group which may have a substituent, and R ₃
And R ₄ each independently represent a phenyl group which may have a substituent. ) A terphenyl derivative represented by
And (2) an electrophotographic photoreceptor having a photosensitive layer on a conductive support, wherein the photosensitive layer contains a compound represented by the general formula (I). To do.

The present invention will be described in detail below.

The terphenyl derivative represented by the general formula (I) of the present invention can be produced by the following method.

That is, the general formula (II)

[0020]

[Chemical 3]

(Wherein R ₁ and R ₂ are the same as those in the above general formula (I)), and 4'-iodo-1,
1 ′: 3 ′, 1 ″ -terphenyl derivative and the general formula (II
I)

[0022]

[Chemical 4] (In the formula, R ₃ and R ₄ are the same as those in the general formula (I).) And a diarylamino compound represented by the general formula (I) without solvent or N, N-dimethylformamide, N, N
1) in a solvent such as dimethyl sulfoxide, sulfolane or nitrobenzene in the presence of a catalyst such as copper powder, copper halide or copper oxide and a basic inorganic salt such as an alkali metal carbonate.
It can be produced by heating and reaction at 50 to 250 ° C.

The 4'-iodo-1,1 ': 3', 1 "-terphenyl derivative represented by the general formula (II) is, for example," ORGANIC PREPARATIONS AND PROCEDURES INT. "1
978, Vol. 10, No. 3, page 143, and the method described in the literature and "BULLETIN DE LA SOCIETECHIMIQUE DE FRANCE" 19
The method shown in the literature on page 276, No. 3-4, or "BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN" 1
It can be manufactured by applying the method described in the literature described in 966, Vol. 39, No. 1, p. 128. If necessary, the general formula (IV)

[0024]

[Chemical 5]

(Wherein R ₁ and R ₂ are the same as those in the general formula (I)), 1,1 ′: 3 ′,
1 ″ -terphenyl-4′-amine derivative and general formula (V)

[0026]

[Chemical 6]

(In the formula, R ₃ represents a phenyl group which may have a substituent, and X represents a halogen atom.)
Or a halogenated aryl compound of
In a solvent such as N, N-dimethylformamide, N, N-dimethylsulfoxide, sulfolane, nitrobenzene,
It can also be produced by heating to 150 to 250 ° C. and reacting with a catalyst such as copper powder, copper halide, or copper oxide in the presence of a basic inorganic salt such as an alkali metal carbonate.

However, the method for producing the terphenyl derivative of the present invention is not necessarily limited to this.

When R ₃ or R ₄ in the terphenyl derivative represented by the general formula (I) of the present invention is a phenyl group having a substituent, the substituent is an alkyl group, a substituted alkyl group, an alkoxy group or a substituted group. Examples thereof include an alkoxy group and a halogen atom. Among them, the alkyl group and the alkoxy group having 1 to 4 carbon atoms are particularly preferable as the photoconductive material.

Examples of compounds of the terphenyl derivative of the present invention are shown below by structural formulas, but the present invention is not necessarily limited to these examples.

In the structural formulas below, Me is a methyl group, Et is an ethyl group, Pr is a propyl group, i-Pr is an isopropyl group, Bu is a butyl group, and sec-Bu is se.
c-Butyl group and t-Bu represent tert-butyl group, respectively, and the number on the left side of the structural formula represents the compound No.

[0032]

[Chemical 7]

[0033]

[Chemical 8]

[0034]

[Chemical 9]

[0035]

[Chemical 10]

[0036]

[Chemical 11]

[0037]

[Chemical 12]

[0038]

[Chemical 13]

[0039]

[Chemical 14]

[0040]

[Chemical 15]

[0041]

[Chemical 16]

[0042]

[Chemical 17]

[0043]

[Chemical 18]

[0044]

[Chemical 19]

[0045]

[Chemical 20]

[0046]

[Chemical 21]

[0047]

[Chemical formula 22]

[0048]

[Chemical formula 23]

[0049]

[Chemical formula 24]

[0050]

[Chemical 25]

[0051]

[Chemical formula 26]

Various materials can be used as the charge generating material used in the electrophotographic photosensitive member of the present invention. For example, azo pigments such as monoazo pigments, disazo pigments and trisazo pigments; various metal phthalocyanines and metal-free metals. Phthalocyanine pigments such as phthalocyanine and naphthalocyanine;
Examples thereof include condensed polycyclic pigments such as perinone pigments, perylene pigments, anthraquinone pigments, and quinacridone pigments; squarylium dyes; azurenium dyes; thiapyrylium dyes; cyanine dyes.

Particularly, phthalocyanines are suitable because they have high sensitivity in an electrophotographic system using a long-wavelength light source such as a semiconductor laser or a light emitting diode.

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

In the charge transporting material for the electrophotographic photosensitive member of the present invention, other known charge transporting materials can be used in combination with the terphenyl derivative of the present invention, if necessary.

Examples of charge transport materials of low molecular weight compounds which can be used in combination include pyrene; carbazoles such as N-ethylcarbazole, N-isopropylcarbazole and N-phenylcarbazole; N-methyl-N-phenylhydrazino. -3-Methylidene-9-ethylcarbazole, N, N-diphenylhydrazino-3-methylidene-
9-ethylcarbazole, p- (N, N-dimethylamino) benzaldehyde diphenylhydrazone, p-
(N, N-diethylamino) benzaldehyde diphenylhydrazone, p- (N, N-diphenylamino) benzaldehyde diphenylhydrazone, 1- [4- (N,
N-Diphenylamino) benzylideneimino] -2,3
-Dimethylindoline, N-ethylcarbazole-3-
Hydrazones such as methylidene-N-aminoindoline and N-ethylcarbazole-3-methylidene-N-aminotetrahydroquinoline; oxa such as 2,5-bis (p-diethylaminophenyl) -1,3,4-oxadiazole Diazoles; 1-phenyl-3- (p-diethylaminostyryl) -5- (p-diethylaminophenyl) pyrazoline, 1- [quinolyl- (2)]-3- (p
-Diethylaminophenyl) pyrazolins and other pyrazolines; tri-p-tolylamine, N, N'-diphenyl-
Aryl amines such as N, N'-bis (3-methylphenyl) -1,1'-biphenyl-4,4'-diamine;
1,1-bis (p-diethylaminophenyl) -4,4
Butadienes such as diphenyl-1,3-butadiene;
Examples thereof include styryls such as 4- (2,2-diphenylethenyl) -N, N-diphenylbenzenamine and 4- (1,2,2-triphenylethenyl) -N, N-diphenylbenzenamine. .

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

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

When these charge transporting materials are used in combination with the terphenyl derivative of the present invention, the content of the terphenyl derivative of the present invention in the total charge transporting material is 5 by weight.
% Or more, preferably 10% or more.

The electrophotographic photosensitive member of the present invention comprises a conductive support and a photosensitive layer containing the terphenyl derivative represented by the general formula (I) formed on the conductive support. Can be taken. Examples thereof are shown in FIGS. 1 to 3.

The electrophotographic photosensitive member of FIGS. 1 and 2 has a charge generating layer 2 mainly composed of a charge generating material on a conductive support 1.
And a charge-transporting material and a charge-transporting layer 3 made of a binder resin as necessary for forming the photosensitive layer.
Are provided respectively. In the electrophotographic photoreceptor of FIG. 3, the charge generating material 5 is provided on the conductive support 1 and the charge transfer medium 6 is used.
A photosensitive layer 4c dispersed therein is provided.

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

The electrophotographic photosensitive member of FIG. 1 is obtained by vapor deposition of a charge generating material or by applying a dispersion obtained by dispersing fine particles of the charge generating material in a solvent in which a binder resin is dissolved, if necessary.
It can be manufactured by drying, and then applying a solution in which the charge transport material is used alone or, if necessary, a binder resin is used in combination and dissolved, and dried.

In the electrophotographic photosensitive member of FIG. 2, a solution in which a charge transporting material is used alone or, if necessary, a binder resin is used in combination is applied onto a conductive support and dried, and then the charge generating material is applied. Or the dispersion of fine particles of the charge generation material in a solvent or a binder resin solution is applied and dried.

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

In the case of the electrophotographic photoreceptors shown in FIGS. 1 and 2, the thickness of the photosensitive layer is not more than 5 μm, preferably 0.01 to 2 μm, and the thickness of the charge transporting layer. The length is 3 to 50 μm, preferably 5 to 30 μm. In the case of the electrophotographic photoreceptor of FIG. 3, the thickness of the photosensitive layer is 3 to 50.
μm, preferably 5 to 30 μm.

The proportion of the charge transport material in the charge transport layer in the electrophotographic photoreceptor of FIGS. 1 and 2 is 5 to 100% by weight.
Can be selected in a timely manner, and preferably in a range of 30 to 80% by weight. The ratio of the charge generation material in the charge generation layer of the electrophotographic photosensitive member of FIGS.
It can be appropriately selected within the range of 100% by weight, and preferably within the range of 30 to 80% by weight. In the electrophotographic photoreceptor of FIG. 3, the proportion of the charge transport material in the photosensitive layer can be appropriately selected within the range of 5 to 99% by weight, and the proportion of the charge generating material is 1 to 50% by weight, preferably Three
Is about 20% by weight. It should be noted that a plasticizer and a sensitizer can be used together with the binder resin in the production of any of the electrophotographic photoreceptors shown in FIGS.

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

The shape of the electrophotographic photosensitive member of the present invention varies depending on the support used, but various shapes such as a drum shape, a flat plate shape, a sheet shape and a belt shape are possible.

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

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

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

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

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

Any known sensitizer can be used as the sensitizer used in the photosensitive layer as needed.

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

Further, in the electrophotographic photoreceptor of the present invention, in order to improve the storage stability, durability and environmental resistance, a deterioration preventing agent such as an antioxidant or a light stabilizer is contained in the photosensitive layer. You can also Examples thereof include phenol compounds, hydroquinone compounds, amine compounds and the like.

Further, in the present invention, in order to improve the adhesion between the conductive support and the photosensitive layer and prevent the injection of free charge from the conductive support to the photosensitive layer, the conductive support and the photosensitive layer If necessary, an adhesive layer or a barrier layer may be provided between the layers.

Materials used for these layers include polymer compounds used for the binder resin, casein, gelatin, ethyl cellulose, nitrocellulose,
Carboxy-methyl cellulose, vinylidene chloride-based polymer latex, styrene-butadiene-based polymer latex, polyvinyl alcohol, polyamide, polyurethane, phenol resin, aluminum oxide, tin oxide,
Titanium oxide or the like can be used, and the film thickness is preferably 1 μm or less.

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

Examples of the coating method include dip coating method, spray coating method, spinner coating method, bead coating method, wire bar coating method, blade coating method, roller coating method and curtain coating method.

The terphenyl derivative of the present invention has excellent durability as a photoconductive material, and the electrophotographic photoreceptor containing this compound in the photosensitive layer has the above-mentioned constitution. As is clear from the above, the electrophotographic photosensitive member has high sensitivity and excellent electrical property stability during repeated use.

[0083]

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

<Example 1> [N, N-di (4-methylphenyl) -1,1 ':
3 ', 1 "-terphenyl-4'-amine (Compound No.
Production of charge transport material 4)] In a 300 ml four-necked flask equipped with a reflux condenser, a thermometer and a stirrer, 4'-iodo-1,1 ': 3', 1 "
-Terphenyl 18.0 g (0.051 mol), p,
p'-ditolylamine 10.0 g (0.051 mol), sulfolane 150 g, potassium carbonate 7.0 g
(0.0826 mol), copper powder 1.0g, 220 ℃
The mixture was heated and stirred for 30 hours. After cooling the reaction mixture to 80 ° C., 300 ml of water was added to the reaction mixture, and the mixture was stirred at 90 ° C. for 1 hour. After stirring, the mixture was left to stand and the supernatant was removed by decantation. Further, add 300 ml of water to the reaction mixture,
After heating and stirring at 90 ° C. for 1 hour and allowing to stand, the supernatant was removed by decantation. 200 ml of dichloromethane was added to the black solid to disperse and dissolve it while applying ultrasonic waves, and the insoluble matter was removed by filtration. Anhydrous sodium sulfate was added to the filtrate, the filtrate was dried, and then the black dye component was removed by column chromatography on silica gel using a hexane-dichloromethane (3: 1) mixed eluent to obtain a pale brown oily substance. It was Again, by column chromatography on silica gel, isolating and purifying with a mixed eluent of hexane-dichloromethane (5: 1),

[0085]

[Chemical 27]

(In the formula, Me represents a methyl group), N, N-di (4-methylphenyl) as a white solid.
6.6 g of -1,1 ': 3', 1 "-terphenyl-4'-amine (charge transport material of compound No. 4) was obtained.
The yield from iodo-1,1 ': 3', 1 "-terphenyl was 30%.

The obtained N, N-di (4-methylphenyl) -1,1 ': 3', 1 "-terphenyl-4'-amine was used as an infrared spectrophotometer IR- manufactured by JASCO Corporation. 810
4 shows the infrared absorption spectrum (KBr tablet method) measured by the method shown in FIG. 4, and FIG. 5 shows the proton NMR spectrum (carbon tetrachloride solution) measured by the high speed sweep correlation nuclear magnetic resonance apparatus RS-1200 manufactured by Hitachi, Ltd. It was

<Example 2> 2 parts of α-type titanyl phthalocyanine and butyral resin (trade name "ESREC BH-3")
1 part of Sekisui Chemical Co., Ltd.) was added to a mixed solution of 52 parts of dichloromethane and 78 parts of 1,1,2-trichloroethane, and the mixture was dispersed and mixed in a sand mill to obtain a charge generation material dispersion liquid. X of the coating film obtained by coating and drying this dispersion liquid
The line diffraction spectrum is shown in FIG.

This dispersion was applied on a polyester film vapor-deposited with aluminum so that the film thickness after drying would be 0.1 μm to form a charge generation layer. Next, the charge transport material 10 of the compound No. 4 obtained in Example 1
Part, polycarbonate resin (trade name "UPILON Z20
0 "(manufactured by Mitsubishi Gas Chemical Co., Inc.) 10 parts by weight dissolved in 36 parts by weight of 1,1,2-trichloroethane and 54 parts by weight of dichloromethane, and a film thickness after drying was 20 μm on the charge generation layer.
And a charge transport layer were formed to obtain an electrophotographic photosensitive member having the layer structure shown in FIG.

About this electrophotographic photosensitive member, an electrostatic copying paper tester (trade name "SP428" manufactured by Kawaguchi Electric Co., Ltd.)
Is used to charge the electrophotographic photosensitive member in the dark by corona discharge of −6 KV, and the surface potential V of the electrophotographic photosensitive member at this time is charged.
₀ (V) was measured. Next, the surface potential V ₁₀ (V) of the electrophotographic photosensitive member when left as it is for 10 seconds was measured. V ₀ and the potential retention of the surface potential of the electrophotographic photosensitive member than the V ₁₀ was calculated _{(DDR (%) :( V 10} / V 0) × 100). Further, with respect to the surface potential V ₁₀ , a wavelength of 780 nm,
Exposure is performed with light having an exposure energy of 1 μW / cm ^{2, and} the exposure amount E is reduced by half from the time until the surface potential becomes half of V _10.
1/2 (μJ / cm ² ) was determined. Furthermore, the surface potential 15 seconds after the start of exposure, that is, the residual potential V _R (V) was measured.

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

<Comparative Example 1> In Example 2, the compound N
o. Formula (VI) in place of the charge transport material of 4

[0093]

[Chemical 28]

An electrophotographic photosensitive member was prepared in the same manner as in Example 2 except that the charge transporting material represented by the formula (Et represents an ethyl group) was used. The electrophotographic photoreceptor was evaluated. The results are shown in Table 1.

<Comparative Example 2> In Example 2, the compound N
o. Formula (VII) in place of the charge transport material of 4

[0096]

[Chemical 29]

(In the formula, Me represents a methyl group and Et represents an ethyl group.) An electrophotographic photosensitive member was prepared and carried out in the same manner as in Example 2 except that the charge transporting material was used. The electrophotographic photosensitive member was evaluated in the same manner as in Example 2. The results are shown in Table 1.

[0098]

[Table 1]

(In the table, the units of the values of V ₀ and V _R are (-V)
The unit of the value of DDR is (%), and the unit of the value of E _1/2 is (μJ / cm ² ). )

As is clear from the results shown in Table 1, the electrophotographic photosensitive member used in Example 2 has a high surface potential at the time of corona charging, has a good surface potential retention rate, and is halved. The exposure amount was small and the sensitivity was good. Further, it has a good surface potential, a surface potential holding ratio, and a sensitivity even after 1,000 times of repeated operation,
Furthermore, the residual potential after exposure was small.

<Examples 3 to 8> In Example 2, instead of the charge transport material of compound No. 4,

[0102]

[Chemical 30]

(Wherein Me represents a methyl group), the charge transporting material of the compound No. 3 represented by the formula:

[0104]

[Chemical 31]

(Wherein Me represents a methyl group), the charge transporting material of the compound No. 17 represented by the formula:

[0106]

[Chemical 32]

(In the formula, Me represents a methyl group), the charge transport material of compound No. 18, represented by the formula

[0108]

[Chemical 33]

(Wherein Et represents an ethyl group), the charge transporting material of compound No. 20, represented by the formula:

[0110]

[Chemical 34]

(Wherein Et represents an ethyl group), the charge transporting material of the compound No. 21 and the formula

[0112]

[Chemical 35]

(In the formula, Me represents a methyl group and Et represents an ethyl group.) Electrophotographic sensitization was conducted in the same manner as in Example 2 except that the charge transporting material of Compound No. 38 was used. A body was prepared and the electrophotographic photosensitive member was evaluated in the same manner as in Example 2. The results are shown in Table 2.

[0114]

[Table 2]

(In the table, the units of the values of V ₀ and V _R are (-V)
The unit of the value of DDR is (%), and the unit of the value of E _1/2 is (μJ / cm ² ). )

<Example 9> Formula (VIII)

[0117]

[Chemical 36]

A phenoxy resin (commercial name "PKH") prepared by dissolving 2 parts of the disazo pigment represented by
A charge generating material dispersion was prepared using a vibrating mill in a solution of 1 part of "H" manufactured by UNION CARBIDE, USA.

This dispersion was applied on a polyester film on which aluminum was vapor-deposited so that the film thickness after drying would be 1 μm to form a charge generation layer.

Next, 10 parts of the charge transporting material of the compound No. 4 produced in Example 1 and 10 parts of a commercial polyester resin (trade name "Vylon 200" manufactured by Toyobo Co., Ltd.) were added to 40 parts of dichloromethane and 1,1,2,1. A coating solution dissolved in a mixed solvent with 60 parts of trichloroethane is applied on the charge generation layer so that the film thickness after drying is 20 μm, and the charge transport layer is formed to have the layer structure shown in FIG. An electrophotographic photoreceptor was obtained.

About this electrophotographic photosensitive member, an electrostatic copying paper tester (trade name "SP428" manufactured by Kawaguchi Electric Co., Ltd.)
Is used to charge the electrophotographic photosensitive member in the dark by corona discharge of −6 KV, and the surface potential V of the electrophotographic photosensitive member at this time is charged.
₀ (V) was measured. Next, the surface potential V ₁₀ (V) of the electrophotographic photosensitive member when left as it is for 10 seconds was measured. The potential holding ratio (DDR: (V ₁₀ / V ₀ ) × 100) of the surface potential of the electrophotographic photosensitive member was calculated from V ₀ and V ₁₀ . Further, by exposing the surface potential V ₁₀ with white light of 5 lux, the time (sec) until the surface potential is reduced to half of the initial surface potential is obtained, and the photosensitivity E _1/2 (lux · sec) is calculated. I asked. Furthermore, the surface potential 15 seconds after the start of exposure, that is, the residual potential V _R (V) was measured.

The results of measuring the darkness and light decay of the surface potential are shown in Table 4 below. In addition, the process of electrification, leaving in the dark for 1 second, exposure for 1 second, neutralization with white light for 0.1 seconds
The measurement results immediately after repeating 000 times are also shown in Table 3 below.

<Comparative Example 3> In Example 9, the compound N
o. The following structural formula (IX) is used instead of the charge transporting material of 4.

[0124]

[Chemical 37]

An electrophotographic photosensitive member was produced in the same manner as in Example 9 except that the charge transporting material represented by the above was used, and the electrophotographic photosensitive member was evaluated in the same manner as in Example 9.
The results are shown in Table 3.

[0126]

[Table 3]

(In the table, the units of the values of V ₀ and V _R are (-V)
The unit of the value of DDR is (%), and the unit of the value of E _1/2 is (μJ / cm ² ). )

As is clear from the results shown in Table 3, the electrophotographic photosensitive member used in Example 9 has a high surface potential at the time of corona charging, and has a good potential holding ratio of the surface potential. The half-time exposure amount was small, and the residual potential after exposure was small. Also, 1,00
Even after the operation was repeated 0 times, the surface potential retention and sensitivity were good, and the residual potential was small.

Example 10 The following structural formula (X)

[0130]

[Chemical 38]

A solution of 35 parts of the disazo pigment represented by 275 parts of 275 parts of the compound No. 4 charge-transporting material and 275 parts of a polycarbonate resin (trade name "UPILON Z200" manufactured by Mitsubishi Gas Chemical Co., Inc.) in 2475 parts of dichloromethane was added. In addition, the mixture was pulverized and mixed by a vibration mill to obtain a dispersion liquid. This dispersion is applied on a polyester film on which aluminum is vapor-deposited with a wire bar, and the thickness after drying 1
It was coated so as to have a thickness of 0 μm to obtain an electrophotographic photosensitive member having the layer structure shown in FIG.

About this electrophotographic photosensitive member, an electrostatic copying paper testing device (trade name "SP428" manufactured by Kawaguchi Electric Co., Ltd.)
By using an electrophotographic photosensitive member in the dark place at -6KV or + 6K
The electrophotographic characteristics were measured by the same method as in Example 9 except that the film was charged by V corona discharge. The results are shown in Table 4 below.

<Comparative Example 4> The compound of Example 10 was used.
Instead of No. 4 charge transport material, the following structural formula (XI)

[0134]

[Chemical Formula 39]

An electrophotographic photosensitive member was produced in the same manner as in Example 10 except that the charge transporting material represented by
The electrophotographic photosensitive member was evaluated in the same manner as in Example 10. The results are shown in Table 4.

[0136]

[Table 4]

(In the table, the unit of the value of V ₀ and V _R is (V), the unit of the value of DDR is (%), and the unit of the value of E _1/2 is (μJ / cm ² ). It is.)

As is clear from Table 4, the electrophotographic photosensitive member used in Example 10 has a good surface potential retention rate after corona charging, and has a small half-exposure amount at the time of exposure.
Moreover, the residual potential after exposure was small.

Example 11 [4,4 ″ -Di-tert-butyl-N, N-diphenyl-1,1 ′: 3 ′, 1 ″ -terphenyl-4′-
Production of amine (charge transport material of compound No. 70)] In a beaker having a capacity of 2 liters, m-terphenyl 120.0
g (0.521 mol), 2,6-di-tert-butyl-p-cresol 149.25 g (0.677 mol)
And 220 ml of nitromethane were charged and stirred at a liquid temperature of 15 ° C. for a while. Aluminum chloride 118.1 was added to this mixture.
A solution prepared by dissolving 1 g (0.886 mol) in 240 ml of nitromethane was added dropwise over 15 minutes, and after the completion of the addition, another 30
Stir for minutes. After completion of the reaction, the reaction solution was poured into 1.5 liters of distilled water and extracted with methylene chloride. After washing the methylene chloride layer with an aqueous sodium carbonate solution and distilled water in this order,
After drying over sodium sulfate overnight, the solvent was distilled off with an evaporator, and the residue was dried under reduced pressure using a vacuum pump. This gave 239.9 g of an oily product. The oily product was stirred in 620 ml of ethanol at room temperature to precipitate white crystals, and the crystals were suction filtered. The crystals obtained were dissolved in 600 ml of ethanol under reflux to give 3
After stirring for 0 minutes, the mixture was allowed to cool and the crystals were separated by suction filtration. The obtained crystals were washed with a small amount of ethanol and then dried under reduced pressure to obtain 46.7 g of 4,4 ″ -di-tert-butyl-1,1 ′: 3 ′, 1 ″ -terphenyl. Was given.

4,4 ''-di-tertiary-butyl-1,1 ': 3', 1 ''-terphenyl 40.0 g (0.117 mol) thus obtained, orthoperiodate diacid Hydrochloride 6.43 g (0.0282 mol), iodine 14.2
5 g (0.0561 mol), acetic acid 470 ml, distilled water 94
ml and concentrated sulfuric acid 15 ml were placed in a 2 liter eggplant-shaped flask and stirred at a liquid temperature of 80 ° C. for 4 hours,
A pale yellow solid precipitated. After allowing the reaction mixture to cool, the supernatant of the reaction solution was removed by decantation. After washing the light yellow solid with distilled water, 500 ml of methylene chloride
Was dissolved in water, washed with an aqueous solution of sodium thiosulfate, and further washed with distilled water. After the methylene chloride layer was dried with sodium sulfate, methylene chloride was distilled off with an evaporator and further dried under reduced pressure with a vacuum pump to obtain 4'-iodo-4,4 "-di-tert-butyl-1. ，
59.11 g of 1 ′: 3 ′, 1 ″ -terphenyl was obtained.

4'-iodo-4,4 "-di-tert-butyl-1,1 obtained by the above method was placed in a four-necked flask having a capacity of 300 ml equipped with a reflux condenser, a thermometer and a stirrer. ': 3', 1 ''-terphenyl 10.0 g
(0.0213 mol), diphenylamine 5.42 g
(0.032 mol), 90 ml of sulfolane, 3.14 g of potassium carbonate and 2.86 g of copper powder are added, and the mixture is heated at 220 ° C. for 30 minutes.
The mixture was heated and stirred for an hour. After the completion of the reaction, the reaction mixture was cooled to 80 ° C., 1.5 liters of distilled water was added to the reaction mixture, the mixture was stirred at 90 ° C. for 1 hour, allowed to stand, and the supernatant was removed by decantation. Furthermore, distilled water 1.
After adding 5 liters, the mixture was heated with stirring at 90 ° C. for 1 hour and allowed to stand, and then the supernatant was removed by decantation. 200 ml of toluene was added to the black solid, ultrasonic waves were applied to disperse and dissolve it, and insoluble matter was removed by filtration. After the toluene solution was dried over anhydrous sodium sulfate, a pale brown oily matter was obtained by removing the black dye component by column chromatography on silica gel using toluene as an eluent.
The pale brown oily substance was again isolated by column chromatography on silica gel with a mixed eluent of hexane-dichloromethane (5: 1) and then recrystallized from acetonitonil to give a compound of the formula

[0142]

[Chemical 40]

(In the formula, t-Bu represents a tert-butyl group), a white solid 4,4 "-di-
Tertiary-butyl-N, N-diphenyl-1,1 ′:
3 ', 1 "-terphenyl-4'-amine (Compound No.
70 charge-transporting material) 2.66 g.

The obtained 4,4 ″ -di-tertiary-butyl-N, N-diphenyl-1,1 ′: 3 ′, 1 ″ -terphenyl-4′-amine was red produced by JASCO Corporation. An infrared absorption spectrum (KBr tablet method) measured by an external spectrophotometer IR-810 is shown in FIG. 7, and a proton NMR spectrum (carbon tetrachloride) measured by a high-speed sweep correlation nuclear magnetic resonance apparatus RS-1200 manufactured by Hitachi, Ltd. Solution) is shown in FIG.

<Example 12> 2 parts of α-type titanyl phthalocyanine and butyral resin (trade name "ESREC BH-
3 "Sekisui Chemical Co., Ltd.) 1 part, dichloromethane 52
Part and 78 parts of 1,1,2-trichloroethane were added to the mixed solvent and dispersed and mixed in a sand mill to obtain a charge generation material dispersion liquid. This dispersion was applied onto a polyester film on which aluminum was vapor-deposited so that the film thickness after drying would be 0.1 μm to form a charge generation layer.

Next, 90 parts of the charge transport material of the compound No. 70 obtained in Example 11, 100 parts of a polycarbonate resin (trade name "UPILON Z200" manufactured by Mitsubishi Gas Chemical Co., Inc.), 105 parts of chlorobenzene and 420 parts of dichloromethane.
Coating solution obtained by dissolving it in a mixed solvent of 10 parts to form a charge transporting layer on the charge generating layer so that the film thickness after drying is 11 μm, thereby forming the layer structure shown in FIG. An electrophotographic photosensitive member having

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

The measurement results of dark decay and light decay of the surface potential are shown in Table 5 below.

<Example 13> In Example 12, instead of the charge transport material of Compound No. 70,

[0150]

[Chemical 41]

(In the formula, Me represents a methyl group, and t-B
u represents a tertiary butyl group. Example 1 except that the charge transport material of Compound No. 71 represented by
An electrophotographic photosensitive member was produced in the same manner as in 2, and the electrophotographic photosensitive member was evaluated in the same manner as in Example 12. The results are shown in Table 5 below.

<Comparative Example 5> The compound of Example 12 was used.
Formula (XII) instead of No. 70 charge transport material

[0153]

[Chemical 42]

An electrophotographic photosensitive member was prepared in the same manner as in Example 12, except that the charge transporting material represented by the formula (Me represents a methyl group) was used. The electrophotographic photoreceptor was evaluated. The results are shown in Table 5 below.

[0155]

[Table 5]

(In the table, the units of the values of V ₀ and V _R are (-V)
The unit of the value of DDR is (%), and the unit of the value of E _1/2 is (μJ / cm ² ). )

As is clear from the results shown in Table 5, the electrophotographic photosensitive members used in Examples 12 and 13 have a high surface potential at the time of corona charging and a potential holding ratio of the surface potential. The results were good, the half-dose of exposure was small, and the residual potential after exposure was small.

Example 14 In Example 12, instead of 90 parts of the charge transport material of Compound No. 70, the compound of the formula (XIII) was used.

[0159]

[Chemical 43]

(Wherein Et represents an ethyl group) and 36 parts of the charge transport material represented by the formula:

[0161]

[Chemical 44]

(In the formula, Me represents a methyl group, and t-B
u represents a tertiary butyl group. An electrophotographic photosensitive member was prepared in the same manner as in Example 12, except that a mixture of 9 parts of the charge transport material of compound No. 74 represented by
The electrophotographic photosensitive member was evaluated in the same manner as in Example 12. The results are shown in Table 6 below.

Further, charging, leaving in the dark for 1 second, exposure for 1 second,
Table 6 also shows the measurement results immediately after repeating the process of removing static electricity for 0.1 second by white light 1,000 times.

<Comparative Example 6> The compound of Example 12 was used.
An electrophotographic photosensitive member was produced in the same manner as in Example 12 except that 45 parts of the charge transport material represented by the formula (XIII) used in Example 14 was used in place of 90 parts of the charge transport material of No. 70. The electrophotographic photosensitive member was evaluated in the same manner as in Example 12. The results are shown in Table 6 below.

Further, charging, leaving in the dark for 1 second, exposure for 1 second,
The measurement results immediately after repeating the process of removing static electricity by white light for 0.1 second 1,000 times are also shown in Table 6 below.

[0166]

[Table 6]

(In the table, the units of the values of V ₀ and V _R are (-V)
The unit of the value of DDR is (%), and the unit of the value of E _1/2 is (μJ / cm ² ). )

As is clear from Table 6, the electrophotographic photosensitive member used in Example 14 has a high surface potential at the time of corona charging, and has a good potential holding ratio of the surface potential.
The half-exposure amount during exposure was small, and the residual potential after exposure was small. Further, it had a good surface potential, a surface potential holding ratio and a sensitivity even after being repeatedly used 1,000 times, and further, the residual potential after exposure was small.

[0169]

INDUSTRIAL APPLICABILITY The terphenyl derivative of the present invention is extremely useful as a material for providing an electrophotographic photoreceptor having excellent durability as a photoconductive material, high sensitivity, and excellent stability of electric characteristics during repeated use. It is useful.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view showing an example of a layer structure that an electrophotographic photoreceptor of the present invention can have.

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

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

FIG. 4 is an infrared absorption spectrum of the terphenyl derivative of compound No. 4.

FIG. 5 is an NMR spectrum of a terphenyl derivative of compound No. 4.

6 is an X-ray diffraction spectrum of the charge generation layer coating film obtained in Example 3. FIG.

FIG. 7 is an infrared absorption spectrum of the terphenyl derivative of Compound No. 70.

FIG. 8: NMR of terphenyl derivative of compound No. 70
It is a spectrum.

[Explanation of symbols]

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

Claims (2)

[Claims] 1. A compound represented by the general formula (I): (In the formula, R ₁ and R ₂ each independently represent hydrogen or an alkyl group which may have a substituent, and R ₃ and R ₄ each independently represent a phenyl which may have a substituent. A terphenyl derivative represented by the formula (1). 2. An electrophotographic photoreceptor having a photosensitive layer on a conductive support, wherein the photosensitive layer contains the compound according to claim 1.