JP3185280B2 - Novel benzyldiphenyl compound, photoreceptor and electroluminescent device using the benzyldiphenyl compound - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a novel compound having a benzyldiphenyl structure. The benzyldiphenyl compound can be used as a light-sensitive material, and more specifically, can be used as a charge-transporting substance for a photoreceptor or an electroluminescent device.

[0002]

2. Description of the Related Art Various organic compounds which can be used as a light-sensitive material or a charge transport material are conventionally known, for example, anthracene derivatives, anthraquinone derivatives, imidazole derivatives, carbazole derivatives, hydrazone derivatives, styryl derivatives and the like. JP-A-142646 discloses the following general formula:

Embedded image [Wherein R _{1 to} R ₆ represent those described in the above publication], and JP-A-58-58551 discloses the following general formula:

Embedded image [Wherein, R _{1 to} R ₈ represent those described in the above publication]. However, when the above-mentioned materials are applied to, for example, a photoreceptor, it is basically required that they have excellent photosensitivity or charge transportability,
Furthermore, compatibility with other members, durability, weather resistance, and the like are also required, and there is no material that satisfies such characteristics.

[0003]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to provide a novel benzyldiphenyl compound which is different from any of the above structures. Another object of the present invention is to provide a photoreceptor using the novel benzyldiphenyl compound. Another object of the present invention is to provide an electroluminescent device using the novel benzyldiphenyl compound for a charge transport layer.

[0004]

Means for Solving the Problems The present invention provides the following general formula [I]:

[0005]

Embedded image A benzyldiphenyl compound represented by the formula:

In the general formula [I], Ar ₁ , Ar ₂ , Ar ₃ ,
Ar ₄ is independently an alkyl group such as a methyl group or an ethyl group, an aralkyl group such as a benzyl group or a phenethyl group, an aryl group such as a phenyl group, a naphthyl group , a biphenyl group, a heterocyclic group. Groups such as thiophene, furan,
It shows residues such as pyridine and thiazole. These groups include an alkyl group such as a methyl group, an alkoxy group such as methoxy,
It may have a halogen atom such as a chlorine atom or a substituent such as a hydroxy group. Desirable Ar ₁ and Ar ₃ are biphenyl groups, which are more effective for improving sensitivity.

Ar ₁ and Ar ₂ and / or Ar ₃ and Ar ₄
Is an integral ring, for example,

Embedded image May be formed.

R ₁ , R ₂ and R _{3 each} independently represent a hydrogen atom, an alkyl group such as a methyl group or an ethyl group, an alkoxy group,
For example, it represents a halogen atom such as a methoxy group or an ethoxy group, for example, a chlorine atom or a bromine atom.

Specific examples of the compound having a benzyldiphenyl structure represented by the general formula [I] include those having the following structural formulas.

[0010]

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[0011]

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[0012]

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[0013]

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[0014]

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[0015]

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[0016]

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[0017]

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[0018]

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[0019]

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[0020]

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[0021]

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The benzyldiphenyl compound represented by the general formula [I] can be synthesized by the following method.

That is, the following general formula [II]:

[0024]

Embedded image [Wherein R ₁ , R ₂ and R ₃ have the same meaning as in the general formula [I]]
And an iodide represented by the following general formulas [III] and [IV]:

[0025]

Embedded image [Wherein Ar ₁ , Ar ₂ , Ar ₃ and Ar ₄ have the same meaning as in the above general formula [I]], and the amino compound represented by Ull is added in the presence of a basic compound or a transition metal compound catalyst and a solvent.
It can be synthesized by a mann reaction.

As the basic compound used in the present invention, hydroxides, carbonates, bicarbonates, and alcoholates of alkali metals are generally used, and quaternary ammonium compounds, aliphatic amines and aromatic amines are used. It is also possible to use organic bases such as amines. Of these, carbonates and bicarbonates of alkali metals and quaternary ammoniums are preferably used. Furthermore, alkali metal carbonates and bicarbonates are most preferred from the viewpoints of reaction rate and thermal stability.

As the transition metal or transition metal compound used in the present invention, for example, Cu, Fe, Co, Ni, Cr, V, Pd,
Metals such as Pt and Ag and their compounds are used,
Copper and palladium and their compounds are preferred in terms of yield. The copper compound is not particularly limited, and most copper compounds are used, but cuprous iodide, cuprous chloride, cuprous oxide, cuprous bromide, cuprous cyanide, cuprous sulfate ,
Cupric sulfate, cupric chloride, cupric hydroxide, cupric oxide,
Cupric bromide, cupric phosphate, cuprous nitrate, cupric nitrate,
Copper carbonate, cuprous acetate, cupric acetate and the like are preferred. Among them, especially, CuCl, CuCl ₂ , CuBr, CuBr ₂ , CuI, Cu
O, Cu ₂ O, CuSO ₄ , and Cu (OCOCH ₃ ) ₂ are preferred in that they are easily available. As a palladium compound,
A halide, a sulfate, a nitrate, an organic acid salt, or the like can be used. The amount of the transition metal and the compound to be used is from 0.5 to 50 of the benzyldiphenyl halide to be reacted.
0 mol%.

The solvent used in the present invention may be any commonly used solvent, but aprotic polar solvents such as nitrobenzene, dimethylformamide, dimethylsulfoxide and N-methylpyrrolidone are preferably used. The reaction of the present invention is generally performed under normal pressure at 100 to 250.
The reaction is carried out at a temperature of ° C., but may be carried out under pressure. After the completion of the reaction, a solid substance precipitated in the reaction solution is removed, and then the solvent is removed to obtain a product.

The benzyldiphenyl compound represented by the general formula [I] can be used as a photosensitive material, and is particularly excellent in charge transportability.

The benzyldiphenyl compound represented by the general formula [I] of the present invention can be used as a photosensitive material for a photoreceptor, particularly as a charge transporting substance. Further, it can be used for a charge transporting layer of an electroluminescent element by utilizing its charge transporting property.

First, the case where the benzyldiphenyl compound represented by the general formula [I] is used as a charge transporting material for a photoreceptor will be described. Various types of photoreceptors are known as photoreceptors, and the benzyldiphenyl-based compound of the present invention can be applied to any type of photoreceptor. For example, a single-layer photoreceptor having a photosensitive layer formed by dispersing a charge generating material and a charge transport material in a resin binder on a support, or a charge generating layer having a charge generating material as a main component is provided on a support. And a so-called laminated photoreceptor provided with a charge transport layer thereon. One or more benzyldiphenyl compounds of the present invention are used as a charge transport material. The benzyldiphenyl compound acts as a charge transporting substance, and can transport the charge carriers generated by absorbing light extremely efficiently.

Further, the benzyldiphenyl compound of the present invention is excellent in ozone resistance and light stability, so that a photosensitive member excellent in durability can be obtained. Furthermore, the benzyldiphenyl compound of the present invention has good compatibility with the binder resin, hardly precipitates crystals, and contributes to improvement in sensitivity and repetition characteristics.

As the charge generating material, bisazo pigments,
Triarylmethane dye, thiazine dye, oxazine dye, xanthene dye, cyanine dye, styryl dye, thiapyrylium dye, pyrylium dye,
Azo pigments, quinacridone pigments, indigo pigments, perylene pigments, polycyclic quinone pigments, bisbenzimidazole pigments, indathrone pigments, squarium salt pigments, azulene pigments, phthalocyanine pigments, pyrrolopyrrole pigments Selenium alloys such as selenium, selenium / tellurium, selenium / arsenic, cadmium sulfide,
Inorganic substances such as cadmium selenide, zinc oxide, and amorphous silicon. In addition, any material that absorbs light and generates charge carriers at an extremely high probability can be used.

Examples of suitable binder resins include, but are not limited to, saturated polyester resins, polyamide resins, acrylic resins, ethylene-vinyl acetate resins, ionically crosslinked olefin copolymers (ionomers), styrene −
Thermoplastic resins such as butadiene block copolymer, polycarbonate, vinyl chloride-vinyl acetate copolymer, cellulose ester, polyimide, styrene resin; epoxy resin, urethane resin, silicone resin, phenol resin, melamine resin, xylene resin, alkyd resin Thermosetting resin such as thermosetting acrylic resin; photocurable resin; and photoconductive resin such as polyvinyl carbazole, polyvinyl pyrene, polyvinyl anthracene, and polyvinyl pyrrole. These can be used alone or in combination. These electrically insulating resins were measured alone to be 1 × 10
It is desirable to have a volume resistance of ¹² Ω · cm or more.

In order to produce a single-layer type photoreceptor, fine particles of a charge generating material are dispersed in a resin solution or a solution in which a charge transporting material and a resin are dissolved, and this is coated on a conductive support and dried. Good. At this time, the thickness of the photosensitive layer is 3 to 3
0 μm, preferably 5 to 20 μm. If the amount of the charge generating material used is too small, the sensitivity is poor, and if it is too large, the chargeability is deteriorated, the mechanical strength of the photosensitive layer is reduced, and the proportion in the photosensitive layer is 1 part by weight of the resin. 0.
The range is from 0.01 to 2 parts by weight, preferably from 0.2 to 1.2 parts by weight.

In order to prepare a laminated photoreceptor, a charge generation material is vacuum-deposited on a conductive support, or dissolved in a solvent such as an amine, and applied. After coating and drying the coating solution prepared by dispersing in the solution in which the binder resin is dissolved if any,
A solution containing a charge transporting material and a binder is coated thereon and dried. At this time, the thickness of the charge generation layer is 4
The thickness is preferably 3 μm or less, more preferably 2 μm or less, and the thickness of the charge transport layer is 3 to 30 μm, and preferably 5 to 50 μm. The proportion of the charge transporting material in the charge transporting layer is 0.2 to 2 parts by weight, preferably 0.3 to 2 parts by weight per 1 part by weight of the binder resin.
1.3 parts by weight.

The photoreceptor of the present invention can be used together with a binder resin together with a plasticizer such as halogenated paraffin, polybiphenyl chloride, dimethylnaphthalene, dibutylphthalate, O-terphenyl, chloranyl, tetracyanoethylene,
Electron-withdrawing sensitizers such as 2,4,7-trinitrofluorenone, 5,6-dicyanobenzoquinone, tetracyanoquinodimethane, tetrachlorophthalic anhydride, 3,5-dinitrobenzoic acid, methyl violet, rhodamine B; Sensitizers such as cyanine dyes, pyrylium salts and thiapyrylium salts may be used. As the electrically insulating binder resin used in the present invention, a binder such as a thermoplastic resin or a thermosetting resin, a photocurable resin, or a photoconductive resin known per se, which is electrically insulating, can be used. . As the conductive support used in the photoreceptor of the present invention, a foil or plate of copper, aluminum, silver, iron, nickel or the like in the form of a sheet or a drum is used, or these metals are used as a plastic film. Etc. that are vacuum-deposited, electroless-plated, etc., or those in which a layer of a conductive compound such as a conductive polymer, indium oxide, or tin oxide is applied or deposited on a support such as paper or a plastic film. Can be

FIGS. 1 to 5 schematically show examples of the constitution of a photoreceptor using the benzylphenyl compound of the present invention. FIG.
Consists of a charge generation material (3) and a charge transport material (2) on a substrate (1).
Is a photoreceptor having a photosensitive layer (4) formed by mixing the compound with a binder, and the benzyldiphenyl compound of the present invention is used as a charge transporting material. FIG. 2 shows a function-separated type photoconductor having a charge generation layer (6) as a photosensitive layer and a charge transport layer (5). The charge transport layer (5) is formed on the surface of the charge generation layer (6). I have. The charge transport layer (5) contains the benzyldiphenyl compound of the present invention. FIG. 3 shows a function-separated type photoreceptor having a charge generation layer (6) and a charge transport layer (5) as in FIG. 2, but the charge transfer layer (5) has a surface opposite to FIG. A generation layer (6) is formed. FIG. 4 shows the photoreceptor of FIG. 1 further provided with a surface protective layer (7). The photosensitive layer (4) has a charge generation layer (6) and a functional separation layer having a charge transport layer (5). It may be a type photoreceptor. FIG. 5 shows that an intermediate layer (8) is provided between the substrate (1) and the photosensitive layer (4). The intermediate layer (8) has improved adhesiveness, improved coating properties, protected the substrate, It can be provided to improve the charge injection property from the substrate to the photosensitive layer.

As the material used for the intermediate layer, polyimide, polyamide, nitrocellulose, polyvinyl butyral, polyvinyl alcohol, aluminum oxide and the like are suitable, and the film thickness is desirably 1 μm or less.

The benzyl diphenyl compound represented by the general formula [I] of the present invention can be applied to a charge transport layer of an electroluminescence device by utilizing its charge transport property. Hereinafter, a case where the benzyldiphenyl compound of the present invention is applied to a charge transport layer of an electroluminescence device will be described. The organic electroluminescent device is composed of at least an organic light emitting layer and a charge transport layer containing a benzyldiphenyl compound between electrodes. FIG. 6 schematically shows an electroluminescent element. In the figure, (11)
Denotes an anode, on which a charge transport layer (12), an organic light emitting layer (13), and a cathode (14) are sequentially laminated, and the charge transport layer is represented by the above general formula [I]. Contains the represented benzyldiphenyl compound. Anode (1) and cathode
By applying a voltage to (4), the organic light emitting layer (3) develops color.

Anode of organic electroluminescence element
As the conductive material used as (11), those having a work function of more than 4 eV are preferable, and carbon, aluminum, vanadium, iron, cobalt, nickel, copper, zinc,
Tungsten, silver, tin, gold and their alloys,
Tin oxide and indium oxide are used. The metal forming the cathode 14 preferably has a work function of less than 4 eV, and magnesium, calcium, titanium, yttrium, lithium, gadolinium, ytterbium, ruthenium, manganese, and alloys thereof are used. In the organic electroluminescence element, at least the anode (11) or the cathode (14) is a transparent electrode so that light emission can be seen. At this time, if a transparent electrode is used for the cathode, the transparency is likely to be impaired. Therefore, it is preferable to use the anode as the transparent electrode. In the case of forming a transparent electrode, a conductive material as described above may be formed on a transparent substrate by means of vapor deposition, sputtering, or the like so as to secure a desired light-transmitting property. As a transparent substrate, it has a moderate strength, when producing an electroluminescent element,
It is not adversely affected by heat due to vapor deposition and the like, and is not particularly limited as long as it is transparent.Examples of such a material include a glass substrate and a transparent resin such as polyethylene, polypropylene, polyether sulfone, and polyether ether ketone. It is also possible to use. As a transparent electrode formed on a glass substrate, commercially available products such as ITO and NESA are known, and those may be used.

The charge transport layer (12) is made of the above-mentioned general formula [I]
May be formed by vapor deposition, or may be formed by spin coating a suitable resin solution of the benzyl diphenyl compound. When formed by a vapor deposition method, the thickness is usually 0.01 to 0.3 μm, and when formed by a spin coating method, the content of the benzyldiphenyl compound is about 20 to 80% by weight based on the binder resin. It may be formed to a thickness of about 0.05 to 1.0 μm so as to have an appropriate amount.

An organic light emitting layer is formed on the charge transport layer (12) thus formed. As the organic light-emitting material used for the organic light-emitting layer, known materials can be used. For example, epidolidine, 2,5-bis [5,7-di-t-pentyl-2-benzoxazolyl] thiophene, 2,2′- (1,
4-phenylenedivinylene) bisbenzothiazole, 2,
2 ′-(4,4′-biphenylene) bisbenzothiazole,
5-methyl-2- {2- [4- (5-methyl-2-benzoxazolyl) phenyl] vinyl} benzoxazole,
5-bis (5-methyl-2-benzoxazolyl) thiophene, anthracene, naphthalene, phenanthrene, pyrene, chrysene, perylene, perinone, 1,4-diphenylbutadiene, tetraphenylbutadiene, coumarin,
Macridine stilbene, 2- (4-biphenyl) -6-phenylbenzoxazole, aluminum trisoxine, magnesium bisoxin, bis (benzo-8-quinolinol) zinc, bis (2-methyl-8quinolinolate) aluminum oxide, indium tris Oxine, aluminum tris (5-methyloxin), lithium oxine, gallium trioxin, calcium bis
(5-chlorooxin), polyzinc-bis (8-hydroxy-5-quinolinonyl) methane) dilithium epindridione, zinc bisoxin, 1,2-phthaloperinone,
Examples thereof include 2-naphthaloperinone. Also, common fluorescent dyes such as fluorescent coumarin dye, fluorescent perylene dye, fluorescent pyran dye, fluorescent thiopyran dye,
Fluorescent polymethine dyes, fluorescent merocyanine dyes, fluorescent imidazole dyes and the like can also be used. Among them, particularly preferred are chelated oxinoid compounds. The organic light-emitting layer may have a single-layer structure of the above-described light-emitting substance, or in order to adjust characteristics such as the color of light emission and the intensity of light emission,
It may have a multilayer structure. Next, the above-described cathode is formed on the organic light emitting layer.

As described above, the charge transport layer (12) is provided on the anode (11).
The case where the light emitting layer (13) and the cathode (14) are sequentially laminated to form an organic luminescence element has been described.
A light emitting layer (13), a charge transport layer (12) and an anode may be sequentially laminated on (14). One set of transparent electrodes is suitable for each electrode such as nichrome wire, gold wire, copper wire, platinum wire, etc. (15)
And the organic luminescence element is connected to both electrodes with an appropriate voltage.
Light is emitted by applying (Vs). The organic electroluminescence element of the present invention is applicable to various display devices, display devices, and the like. Hereinafter, the present invention will be described with reference to specific examples. In the following examples, “parts” means “parts by weight” unless otherwise specified.

Synthesis Example 1 Synthesis Example of Compound [2] 50 g of 4-iododiphenyl-4'-p-iodobenzyl
(0.10 mol), 3-methyldiphenylamine 44 g
(0.24 mol), 35 g (0.3 mol) of potassium carbonate, 10 g (0.16 mol) of copper powder and 400 g of nitrobenzene were charged into a 1-liter four-necked flask equipped with a reflux condenser, and the mixture was placed under a nitrogen stream. At 200 ° C. for 18 hours. After completion of the reaction, 200 g of tetrahydrofuran was added to the reaction solution, and the solid was filtered. After the filtrate was separated by silica gel column chromatography, the separated product was purified by recrystallization in a mixed solvent of toluene and ethanol to obtain white crystals having a melting point of 75 to 76 ° C. The results of the elemental analysis are as follows (C ₄₅ H ₃₈ N ₂
As). ───────────────────── C (%) H (%) N (%) ─────────────────計算 Calculated 89.11 6.27 4.62 ───────────────────── Experimental 89.06 6.24 4.60 ─────────────────────赤 外 Further, the infrared absorption spectrum of the obtained compound is shown in FIG. Synthesis Example 2 Synthesis Example of Compound [5] In the same manner as in Synthesis Example 1, except that 47 g of 4.4′-dimethyldiphenylamine was used instead of 3-methyldiphenylamine, and after the reaction was completed, tetrahydrofuran was added to the reaction solution. 200 g was added, then the solid was filtered. After the filtrate was separated by silica gel column chromatography, the separated product was purified by recrystallization in a mixed solvent of toluene and ethanol to obtain oily white crystals. The results of the elemental analysis are as follows (as C ₄₇ H ₄₂ N ₂ ): C (%) H (%) N ( %) 計算 Calculated value 88.96 6.62 4.42 ──────────────────── ─ Experimental value 88.91 6.57 4.38 赤 外 The infrared absorption spectrum of the obtained compound is shown in FIG.

Synthesis Example 3 Synthesis Example of Compound [43] The synthesis was performed in the same manner as in Synthesis Example 1, except that 62.2 g of Np-tolyl-N-biphenylamine was used instead of 3-methyldiphenylamine. After the reaction, nitrobenzene was distilled off by steam distillation, and toluene 400
g was added and the solid was filtered. After the filtrate was separated by silica gel column chromatography, the separated product was purified by recrystallization from isopropyl ether to obtain 4.9 g of white crystals.
The melting point was 148~149 ⁰ C. The results of the elemental analysis are as follows (as C ₅₇ H ₄₆ N ₂ ): C (%) H (%) N ( %) ───────────────────── Calculated 90.24 6.07 6.69 ───────────────────── Experiment Value 90.21 6.05 3.66 赤 外 The infrared absorption spectrum of the compound obtained is shown in FIG.

Application of Separable Function Photoreceptor to Charge Transport Material Example 1 Bisazo compound represented by the following general formula [A]

Embedded image 0.45 parts of a polyester resin (Vylon 200; manufactured by Toyobo Co., Ltd.) and 0.45 parts of the resin were dispersed together with 50 parts of cyclohexanone by a sand mill. Using a film applicator, apply a dry film thickness of 0.3 g to the obtained dispersion of the bisazo compound on a 100 μm-thick aluminized mylar.
/ M ² and dried.

On the charge generation layer thus obtained, 50 parts of a benzyldiphenyl compound [1] and a polycarbonate resin (Panlite K-1300; manufactured by Teijin Chemicals Ltd.) 5
A solution prepared by dissolving 0 parts in 400 parts of 1,4-dioxane was applied so as to have a dry film thickness of 16 μm, and dried to form a charge transport layer. Thus, an electrophotographic photoreceptor having two photosensitive layers was obtained.

The photoreceptor thus obtained was applied to a commercially available electrophotographic copying machine (EP-450Z, manufactured by Minolta Camera Co., Ltd.).
Was corona charged at -6 kV, the initial surface potential V ₀ (V), the exposure amount required to initial potential to the _{1/2 E 1/2 (lux ·} se
c) Decay rate DD of initial potential when left in the dark for 1 second
R ₁ (%) was measured.

Examples 2 to 4 In the same manner as in Example 1, but having the same constitution, except that the benzyldiphenyl compound [1] used in Example 1 was replaced with benzyldiphenyl compounds [2] and [3] And [4] were prepared. About the photoreceptor thus obtained,
It was measured _{V 0, E 1/2,} DDR 1 in the same manner as in Example 1.

Example 5 Bisazo compound represented by the following general formula [B]

Embedded image 0.45 parts, polystyrene resin (molecular weight 40000)
45 parts were dispersed together with 50 parts of cyclohexanone by a sand mill.

The obtained dispersion of the bisazo compound was applied to a thickness of 1
Using a film applicator, the film was coated on a 00 μm aluminized mylar using a film applicator to a dry film thickness of 0.3 g / m ² and then dried. On the charge generation layer thus obtained, 50 parts of a benzyldiphenyl compound [5] and 50 parts of a polyarylate resin (U-100; manufactured by Unitika) were placed in 1,
A solution dissolved in 400 parts of 4-dioxane has a dry film thickness of 2
It was applied so as to have a thickness of 0 μm and dried to form a charge transport layer. Thus, an electrophotographic photosensitive member having a two-layer photosensitive layer was produced.

Examples 6 to 9 In the same manner as in Example 5, but with the same constitution, except that the benzyldiphenyl compound [5] used in Example 5 was replaced with a benzyldiphenyl compound [6], [7] , [8] and [43] were prepared. The thus obtained photosensitive member, in the same manner as in Example _{1 V 0, E 1/2} , DD
It was measured R _1.

Example 10 Polycyclic quinone pigment represented by the following general formula [C]

[0055]

Embedded image 0.45 parts, polycarbonate resin (Panlite K-1
3000: Teijin Chemicals Ltd.) 0.45 part of dichloroethane 5
It was dispersed by a sand mill together with 0 parts. The resulting dispersion of the polycyclic quinone pigment was applied onto a 100-μm-thick aluminized mylar using a film applicator so that the dry film thickness was 0.4 g / m ^2, and then dried. On the charge generation layer thus obtained, 60 parts of a benzyldiphenyl compound [9] and a polyarylate resin (U-1)
00; manufactured by Unitika Ltd.) and 50 parts of 1,4-dioxane 400
The solution dissolved in the portion was applied so as to have a dry film thickness of 18 μm, and dried to form a charge transport layer. Thus, an electrophotographic photosensitive member having a two-layer photosensitive layer was produced.

Examples 11 to 14 In the same manner as in Example 10, but with the same constitution, except that the benzyl diphenyl compound [9] used in Example 10 was replaced with benzyl diphenyl compounds [10] and [11] , [4
8] and [54]. The photoconductor obtained in this manner was subjected to V
_0, was measured E _1/2, DDR _1.

Example 15 A perylene pigment represented by the following general formula [D]

Embedded image 0.45 part of butyral resin (BX-1; manufactured by Sekisui Chemical Co., Ltd.) was dispersed in a sand mill together with 50 parts of dichloroethane. The resulting perylene pigment dispersion was applied on a 100 μm-thick aluminized mylar using a film applicator so that the dry film thickness was 0.4 g / m ^2, and then dried. A solution prepared by dissolving 50 parts of a benzyldiphenyl compound [12] and 50 parts of a polycarbonate resin (PC-Z; manufactured by Mitsubishi Gas Chemical Company) in 400 parts of 1,4-dioxane on the charge generation layer thus obtained. Was applied to a dry film thickness of 18 μm to form a charge transport layer. Thus, an electrophotographic photosensitive member having a two-layer photosensitive layer was produced.

Examples 16 to 19 In the same manner as in Example 15, but having the same constitution, except that the benzyl diphenyl compound [12] used in Example 15 was replaced with benzyl diphenyl compounds [13] and [14] , [3
0] and [42]. The photoconductor obtained in this manner was subjected to V
_0, was measured E _1/2, DDR _1.

Example 20 0.45 part of titanyl phthalocyanine, butyral resin
0.45 part (BX-1; manufactured by Sekisui Chemical Co., Ltd.) was dispersed together with 50 parts of dichloroethane by a sand mill. Using a film applicator, the obtained dispersion of the phthalocyanine pigment was put on an aluminized mylar having a thickness of 100 μm.
The coating was applied so that the dry film thickness became 0.3 g / m ^2, and then dried. A solution obtained by dissolving 50 parts of a benzyldiphenyl compound [15] and 50 parts of a polycarbonate resin (PC-Z; manufactured by Mitsubishi Gas Chemical Company) in 400 parts of 1,4-dioxane on the charge generation layer thus obtained. Was applied to a dry film thickness of 18 μm to form a charge transport layer. Thus, an electrophotographic photosensitive member having a two-layer photosensitive layer was produced.

Examples 21 to 24 In the same manner as in Example 20, but having the same constitution, except that the benzyl diphenyl compound [15] used in Example 20 was replaced with benzyl diphenyl compounds [16] and [17] , [4
8] and [58] were prepared. The photoconductor obtained in this manner was subjected to V
_0, was measured E _1/2, DDR _1.

Example 25 50 parts of copper phthalocyanine and 0.2 parts of tetranitro copper phthalocyanine were dissolved in 500 parts of 98% concentrated sulfuric acid with sufficient stirring, and the mixture was poured into 5000 parts of water. After precipitating the conductive material composition, it was filtered, washed with water, and dried at 120 ° C. under reduced pressure. 10 parts of the photoconductive composition thus obtained were mixed with 22.5 parts of a thermosetting acrylic resin (Acrydic A405; manufactured by Dainippon Ink) and a melamine resin (Super Beckamine J).
820; manufactured by Dainippon Ink Co., Ltd.) 7.5 parts and 15 parts of a benzyldiphenyl compound [18] are put in a ball mill pot together with 100 parts of a mixed solvent prepared by mixing methyl ethyl ketone and xylene in the same amount, and dispersed for 48 hours. A coating solution was prepared, and the coating solution was applied on an aluminum substrate and dried to form a photosensitive layer having a thickness of about 15 μm, thereby producing a photoreceptor. The thus obtained photosensitive member performs the same method as that in Example 1, except that the corona charging at _{+ 6Kv, V 0, E 1} /2,
DDR ₁ was measured.

Examples 26 to 30 In the same manner as in Example 25, but with the same constitution, except that the benzyl diphenyl compound [18] used in Example 25 was replaced with a benzyl diphenyl compound [21], [23] , [2
6], [42] and [45] were prepared. The thus obtained photosensitive member was measured _{V 0, E 1/2,} DDR 1 in the same manner as in Example 25.

Comparative Examples 1 to 4 In the same manner as in Example 25, but having the same constitution, except that the benzyldiphenyl compound used in Example 25 was replaced by the following compounds [E], [F], [G], A photoconductor was prepared in the same manner as that of Example 25 except that each of [H] was used.

Embedded image The thus obtained photosensitive member was measured _{V 0, E 1/2,} DDR 1 in the same manner as in Example 25.

Comparative Examples 5 to 7 In the same manner as in Example 25, but having the same constitution, except that the benzyldiphenyl compound [18] used in Example 25 was replaced with the following compounds [I], [J], and [J]. A photosensitive member was produced in exactly the same manner as in Example 18 except that each of [K] was used.

Embedded image The thus obtained photosensitive member was measured _{V 0, E 1/2,} DDR 1 in the same manner as in Example 25. Examples 1-3
0, V ₀ of the resulting photosensitive member in Comparative Example 1~7, E _1/2, D
The measurement results of DR ₁ are summarized in Table 1 and Table 2.

[0065]

[Table 1]

[0066]

[Table 2]

As can be seen from Tables 1 and 2, the photoreceptor of the present invention has a sufficient charge retention ability, whether it is a laminated type or a single layer type, and has a dark decay rate small enough to be used as a photoreceptor. And the sensitivity is excellent. Furthermore, a commercially available electrophotographic copying machine (Minolta Camera Co., Ltd .; EP-350Z)
Was carried out on the photoreceptor of Example 25 by using the photoreceptor of Example 25. Even when 1000 copies were made, the initial and final images were excellent in gradation, no change in sensitivity, and a clear image was obtained. This indicates that the photoreceptor of the present invention has stable repetition characteristics.

[0068]

The present invention provides a novel benzyldiphenyl compound. The benzyl diphenyl compound provided by the present invention can be used for a photoreceptor and a charge transport layer of an electroluminescence device. The photoreceptor in which the benzyldiphenyl compound of the present invention is applied to the charge transport layer has sensitivity,
Excellent photoreceptor characteristics such as charge transportability, initial surface potential, and dark decay rate, and less light fatigue due to repeated use.

[Brief description of the drawings]

FIG. 1 is a schematic view of a dispersion type photoconductor in which a photoconductive layer is laminated on a conductive support.

FIG. 2 is a schematic diagram of a function-separated type photoconductor in which a charge generation layer and a charge transport layer are laminated on a conductive support.

FIG. 3 is a schematic view of a function-separated type photoconductor in which a charge transport layer and a charge generation layer are laminated on a conductive support.

FIG. 4 is a schematic diagram of a photosensitive member in which a photosensitive layer and a surface protective layer are formed on a conductive support.

FIG. 5 is a schematic diagram of a photoconductor in which an intermediate layer and a photosensitive layer are formed on a conductive support.

FIG. 6 shows a schematic sectional view of an electroluminescent device.

FIG. 7 is a view showing an infrared absorption spectrum of an example of a benzyldiphenyl compound of the present invention.

FIG. 8 is a view showing an infrared absorption spectrum of an example of a benzyldiphenyl compound of the present invention.

FIG. 9 is a view showing an infrared absorption spectrum of an example of a benzyldiphenyl compound of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Substrate 2 Charge transport material 3 Charge generation material 4 Photosensitive layer 5 Charge transport layer 6 Charge generation layer 7 Surface protective layer 8 Intermediate layer 11 Anode 12 Charge transport layer 13 Organic light emitting layer 14 Cathode

──────────────────────────────────────────────────続 き Continued on the front page (58) Fields investigated (Int. Cl. ⁷ , DB name) C07C 211/00 C07C 217/00 C07D 307/00 C07D 333/00 G03G 5/06 CA (STN) REGISTRY (STN )

Claims (3)

(57) [Claims] 1. The following general formula [I]: [Wherein _{Ar 1, Ar 2, Ar 3} , Ar 4 are independently an alkyl group selected from the main <br/> methyl group or an ethyl group, an aralkyl group selected from benzyl group or a phenethyl group, a phenyl or naphthyl Represents a heterocyclic group selected from an aryl group, a biphenyl group, a thienyl group, a furyl group, a pyridyl group, and a thiazolyl group.
And these groups are methyl, ethyl, methoxy,
Having a substituent selected from a halogen atom or a hydroxy group.
It may be in; Ar ₁ and Ar ₂ and / or Ar ₃
And Ar ₄ together form the following ring: R ₁ , R ₂ and R ₃ independently represent a hydrogen atom, an alkyl group selected from a methyl group or an ethyl group, an alkoxy group selected from a methoxy group or an ethoxy group, or a halogen atom. ] The benzyl diphenyl compound represented by these. 2. The following general formula [I]: [Wherein _{Ar 1, Ar 2, Ar 3} , Ar 4 are independently an alkyl group selected from the main <br/> methyl group or an ethyl group, an aralkyl group selected from benzyl group or a phenethyl group, a phenyl or naphthyl Represents a heterocyclic group selected from an aryl group, a biphenyl group, a thienyl group, a furyl group, a pyridyl group, and a thiazolyl group.
And these groups are methyl, ethyl, methoxy,
Having a substituent selected from a halogen atom or a hydroxy group.
It may be in; Ar ₁ and Ar ₂ and / or Ar ₃
And Ar ₄ together form the following ring: R ₁ , R ₂ and R ₃ independently represent a hydrogen atom, an alkyl group selected from a methyl group or an ethyl group, an alkoxy group selected from a methoxy group or an ethoxy group, or a halogen atom. A photoreceptor comprising a benzyldiphenyl compound represented by the formula: 3. The following general formula [I]: [Wherein _{Ar 1, Ar 2, Ar 3} , Ar 4 are independently an alkyl group selected from the main <br/> methyl group or an ethyl group, an aralkyl group selected from benzyl group or a phenethyl group, a phenyl or naphthyl Represents a heterocyclic group selected from an aryl group, a biphenyl group, a thienyl group, a furyl group, a pyridyl group, and a thiazolyl group.
And these groups are methyl, ethyl, methoxy,
Having a substituent selected from a halogen atom or a hydroxy group.
It may be in; Ar ₁ and Ar ₂ and / or Ar ₃
And Ar ₄ together form the following ring: R ₁ , R ₂ and R ₃ independently represent a hydrogen atom, an alkyl group selected from a methyl group or an ethyl group, an alkoxy group selected from a methoxy group or an ethoxy group, or a halogen atom. An electroluminescent device comprising the benzyldiphenyl compound represented by the formula [1] as a charge transporting substance.