JPH04282349A - Distyryl compound and its production - Google Patents

Abstract

PURPOSE:To obtain a new distyryl compound useful as photosensitive units excellent in characteristics thereof and durability or electroluminescent elements, having high luminous intensity and excellent in durability in which the aforementioned new distyryl compound is used as a charge transport material. CONSTITUTION:A compound expressed by formula I (R1 is alkyl or aryl which may have substituent group; R2 is respective groups in R1 or aralkyl; R3 is respective groups in R1, vinyl, ethynyl, benzyl, furyl, thienyl, alkoxy, aralkyloxy, phenoxy, thioalkyl, thioaralkyl or thiophenyl), e.g. a compound expressed by formula II. The aforementioned compound can be produced by reacting a compound expressed by formula III (R4 is lower alkyl) with a compound expressed by formula IV. Furthermore, the above-mentioned compound can be utilized as electrophotographic organic photoconductive materials, fluorescent brighteners, optical recording materials, electrochromic elements or electroluminescent elements and photosensitive units containing the aforementioned compound applied to a charge transport layer are excellent in characteristics thereof such as sensitivity, charge transportability, initial surface potential and dark decay without any optical fatigue even by repeated use.

Description

[Detailed description of the invention]

0001

TECHNICAL FIELD The present invention relates to a novel distyryl compound and a method for producing the same. Specifically, the distyryl compound of the present invention is an organic photoconductive material for electrophotography,
Fluorescent brighteners, optical recording materials, electrochromic devices,
Alternatively, it can be used as an electroluminescent element.

0002

BACKGROUND OF THE INVENTION Various organic compounds that can be used as photoconductive materials have been known, such as anthracene derivatives, anthraquinone derivatives, imidazole derivatives, carbazole derivatives, hydrazone derivatives, and styryl derivatives. Asymmetric distyryl compounds are disclosed in JP-A No. 175052 or JP-A-62-120346. However, the current situation is that fully satisfactory characteristics have not been obtained.

0003

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a novel distyryl compound having a structure different from any of the above-described structures. A further object of the present invention is to provide a photoreceptor using the novel distyryl compound in a charge transport layer. A further object of the present invention is to provide an electroluminescent device using the novel distyryl compound in a charge transport layer.

0004

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

[Formula, R1 represents an alkyl group or an aryl group which may have a substituent; R2 represents an alkyl group, an aralkyl group, or an aryl group which may have a substituent; R3 represents an alkyl group , vinyl group, ethynyl group, benzyl group, aryl group which may have a substituent, furyl group, thienyl group, alkoxy group, aralkyloxy group, phenoxy group, thioalkyl group, thioaralkyl or thiophenyl group. ] A distyryl compound represented by the following and a method for producing the same are provided.

The distyryl compound represented by the general formula [I] has excellent charge transport properties.

In the general formula [I], R1 represents an alkyl group such as a methyl group or an ethyl group, or an aryl group such as a phenyl group or naphthyl group. The aryl group may have a substituent such as a lower alkyl group, a lower alkoxy group, a phenyl group, or a halogen atom. R2 represents an alkyl group such as a methyl group or an ethyl group, an aralkyl group such as benzyl or phenethyl, or an aryl group such as a phenyl group or a naphthyl group. The aryl group may have a substituent such as a lower alkyl group, a lower alkoxy group, a phenyl group, or a halogen atom. R3 is an alkyl group such as a methyl group, an ethyl group or a propyl group, an alkenyl group such as a vinyl group,
Alkynyl group such as ethynyl group, aralkyl group such as benzyl group or phenethyl group, aryl group such as phenyl group or naphthyl group, furan, thiophene or 1,
Heterocyclic residues such as 3-dioxaindane, alkoxy groups such as methoxy or ethoxy, aralkyloxy groups such as benzyloxy and phenethyloxy groups, thioalkyl groups such as phenoxy, thiomethyl and thioethyl groups, and thioaralkyl such as thiobenzyl groups. Or represents a thiophenyl group. The aryl group is a C1 to C4 alkyl group or a substituent such as an alkoxy group, a halogen atom, or a hydroxyl group.
It may have one or two or more.

Specific examples of the distyryl compound represented by the general formula [I] include those having the following structural formula.

[0008]

[Chemical formula 10]

[0009]

[Chemical formula 11]

0010

[Chemical formula 12]

[0011]

[Chemical formula 13]

0012

[Chemical formula 14]

[0013]

[Chemical formula 15]

[0014]

[Chemical formula 16]

[0015]

[Chemical formula 17]

[0016]

[Chemical formula 18]

[0017]

[Chemical formula 19]

The distyryl compound represented by the general formula [I] can be synthesized by the following two methods. That is, the distyryl compound represented by the general formula [I] has the following general formula [II]:

[In the formula, R1 has the same meaning as R1 in general formula [I], R
4 represents a lower alkyl group] and the following general formula [III]

embedded image [wherein R2 and R3 have the same meanings as R2 and R3 in general formula [I] of claim 1. ] It can be synthesized by reacting with an aldehyde compound represented by the following general formula [IV] or [V]:

embedded image [wherein, R3 has the same meaning as R3 in general formula [I]; R5 represents a lower alkyl group. ]

[In the formula, R3 has the same meaning as R3 in the general formula [I]; X represents a halogen atom] and the following general formula [VI]:

embedded image [wherein R1 and R2 are R1 and R2 in general formula [I]
It has the same meaning as ] It can be synthesized by reacting with an aldehyde compound represented by. The phosphorus compound represented by the general formula [II] or [IV] used in the synthesis of the present invention can be easily obtained by heating the corresponding halomethyl compound and trialkyl phosphite directly or in a solvent such as toluene or xylene. can be manufactured. The trialkyl phosphite is preferably an alkyl group having 1 to 4 carbon atoms, particularly a methyl group or an ethyl group. General formula [V]
The phosphorus compound represented by
It can be easily produced by heating in a solvent such as xylene. General formula [I
A phosphorus compound represented by I], [IV] or [V] and an aldehyde compound represented by general formula [III] or [VI] are reacted at a temperature from room temperature to about 1000C in the presence of a basic catalyst. let As the solvent in this reaction,
For example, hydrocarbons, alcohols, and ethers are good;
Methanol, ethanol, isopropanol, butanol, 2-methoxyethanol, 1,2-dimethoxyethane, bis(2-methoxyethyl) ether, dioxane, tetrahydrofuran, toluene, xylene, dimethyl sulfoxide, N,N-dimethylformamide, N-methyl Examples include pyrrolidone and 1,3-dimethyl-2-imidazolidinone. Among them, polar solvents such as N,N
-Dimethylformamide and dimethylsulfoxide are preferred. As the basic catalyst (condensing agent), caustic soda, caustic potash, sodium amide, sodium hydroxide, and alcoholates such as sodium methylate and potassium t-butoxide are used. The reaction temperature can be selected from a wide range of about 00C to about 1000C. Preferably it is 100C to about 800C. The distyryl compound represented by the general formula [I] of the present invention can be used as a charge transport material for a photoreceptor by utilizing its charge transport properties, particularly its high photoconductivity upon irradiation with light. Also,
Taking advantage of its conductivity, it can be used in charge transport layers of electroluminescent devices.

First, the case where the distyryl compound represented by the general formula [I] is used as a charge transport material for a photoreceptor will be explained. Various types of photoreceptors are known as photoreceptors, and the distyryl-based charge transport material of the present invention can be applied to any of these types of photoreceptors. For example, a single-layer photoreceptor in which a photosensitive layer made of a charge-generating material and a charge-transporting material dispersed in a resin binder is provided on a support;
There is a so-called laminated photoreceptor in which a charge generation layer containing a charge generation material as a main component is provided on a support, and a charge transport layer is provided thereon. One or more distyryl compounds of the present invention are used in a charge transport material. The distyryl compound acts as a photoconductive substance and can very efficiently transport charge carriers generated by absorbing light.

Furthermore, since the distyryl compound of the present invention has excellent ozone resistance and light stability, a photoreceptor with excellent durability can be obtained. Furthermore, the distyryl compound of the present invention has good compatibility with the binder resin, is less likely to cause crystal precipitation, and contributes to improved sensitivity.

[0021] As the charge generating material, bisazo pigments,
Triarylmethane dyes, thiazine dyes, oxazine dyes, xanthene dyes, cyanine dyes, styryl dyes, pyrylium dyes, azo pigments, quinacridone pigments, indigo pigments, perylene pigments, polycyclic quinone dyes Organic substances such as pigments, bisbenzimidazole pigments, indathrone pigments, squalium salt pigments, azulene pigments, and phthalocyanine pigments, selenium,
Examples include inorganic substances such as tellurium, selenium alloys such as selenium and arsenic, cadmium sulfide, cadmium selenide, zinc oxide, and amorphous silicon. In addition to these materials, any material can be used as long as it absorbs light and generates charge carriers with an extremely high probability.

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. -butadiene block copolymer, polycarbonate, vinyl chloride-vinyl acetate copolymer, cellulose ester,
Thermoplastic resins such as polyimide and styrene resins; Thermosetting resins such as epoxy resins, urethane resins, silicone resins, phenol resins, melamine resins, xylene resins, alkyd resins, and thermosetting acrylic resins; Photocurable resins; polyvinyl carbazole, Photoconductive resins such as polyvinylpyrene, polyvinylanthracene, and polyvinylpyrrole. These can be used alone or in combination. These electrically insulating resins are 1×1 when measured individually.
It is desirable to have a volume resistance of 0.012 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 containing a charge transporting material and a resin, and this is coated on a conductive support and dried. good. The thickness of the photosensitive layer at this time is 3 to 3
The thickness is preferably 0 μm, preferably 5 to 20 μm. If the amount of the charge generating material used is too small, the sensitivity will be poor, and if it is too large, the charging property will be poor and the mechanical strength of the photosensitive layer will be weakened. Te 0
．． The range is 0.01 to 2 parts by weight, preferably 0.2 to 1.2 parts by weight. The proportion of the charge transport material is 0.2 to 2 parts by weight, preferably 0.3 to 1.3 parts by weight, per 1 part by weight of the resin. If it is less than 0.2 part by weight, the sensitivity will be poor;
Sensitivity changes during repeated use become large, and if the amount exceeds 2 parts by weight, durability deteriorates and surface potential decreases greatly during repeated use.

In order to produce a laminated photoreceptor, a charge generating material is vacuum deposited on a conductive support, or it is dissolved in a solvent such as amine and coated, or a pigment is coated in a suitable solvent or as necessary. After applying and drying a coating solution prepared by dispersing the binder resin in a solution,
It is obtained by applying a solution containing a charge transporting material and a binder thereon and drying it. The thickness of the charge generation layer at this time is 4
The thickness of the charge transport layer is preferably 3 to 30 μm, preferably 5 to 50 μm. The ratio of charge transport material in the charge transport layer is 1 part binder resin
0.2 to 2 parts by weight, preferably 0.3 parts by weight
~1.3 parts by weight.

In addition to the binder resin, the photoreceptor of the present invention contains plasticizers such as halogenated paraffin, polychlorinated biphenyl, dimethylnaphthalene, dibutyl phthalate, and O-terphenyl, as well as chloranil, tetracyanoethylene, and
, 4,7-trinitrofluorenone, 5,6-dicyanobenzoquinone, tetracyanoquinodimethane, tetrachlorophthalic anhydride, 3,5-dinitrobenzoic acid and other electron-withdrawing sensitizers, methyl violet, rhodamine B, cyanine Sensitizers such as dyes, pyrylium salts, thiapyrylium salts, etc. may also be used. As the electrically insulating binder resin used in the present invention, electrically insulating binders such as thermoplastic resins, thermosetting resins, photocuring resins, photoconductive resins, etc., which are known per se, can be used. . As the conductive support used in the photoreceptor of the present invention, a sheet or drum-shaped foil or plate of copper, aluminum, silver, iron, nickel, etc. is used, or a plastic film made of these metals is used. A layer of a conductive compound such as a conductive polymer, indium oxide, or tin oxide is coated or deposited on a support such as paper or a plastic film by vacuum deposition or electroless plating. It will be done.

Examples of the structure of a photoreceptor using the distyryl compound of the present invention are schematically shown in FIGS. 1 to 5. Figure 1 shows a photocharge generating material (3) and a charge transporting material (2) on a substrate (1).
This is a photoreceptor on which a photosensitive layer (4) is formed, in which the distyryl compound of the present invention is used as a charge transport material. FIG. 2 shows a charge generation layer (6
) and a charge transport layer (5), and the charge transport layer (5) is formed on the surface of the charge generation layer (6). The distyryl compound of the present invention is blended into the charge transport layer (5). FIG. 3 shows a functionally separated photoreceptor having a charge generation layer (6) and a charge transport layer (5) as in FIG. 2, but contrary to FIG. A generation layer (6) is formed. FIG. 4 shows a photoreceptor shown in FIG. 1 in which a surface protective layer (7) is further provided on the surface of the photoreceptor, and the photosensitive layer (4) includes a charge generation layer (6) and a charge transport layer (
5) may be a functionally separated photoreceptor. In FIG. 5, an intermediate layer (8) is provided between the substrate (1) and the photosensitive layer (4), and the intermediate layer (8) is used to improve adhesion, coatability, protect the substrate, It can be provided to improve charge injection properties from the substrate to the photosensitive layer.

Suitable materials for the intermediate layer include polyimide, polyamide, nitrocellulose, polyvinyl butyral, polyvinyl alcohol, and aluminum oxide, and the film thickness is preferably 1 μm or less.

The distyryl compound represented by the general formula [I] of the present invention can also be applied to a charge transport layer of an electroluminescent device by utilizing its charge transport properties. below,
A case in which the distyryl compound of the present invention is applied to a charge transport layer of an electroluminescent device will be described. An organic electroluminescent device is composed of at least an organic light-emitting layer and a charge transport layer containing a distyryl compound between electrodes. FIG. 6 schematically shows an electroluminescent device. In the figure, (11) is 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 contains a distyryl compound represented by the above general formula [I]. The organic light-emitting layer (3) develops color by applying a voltage to the anode (1) and the cathode (4).

Anode of organic electroluminescent device (
The conductive material used as 1) preferably has a work function larger than 4 eV, and includes carbon, aluminum, vanadium, iron, cobalt, nickel, copper, zinc, tungsten, silver, tin, gold, etc. Alloys, tin oxide, and indium oxide are used. The metal forming the cathode (4) preferably has a work function smaller than 4 eV, such as magnesium, calcium, titanium,
Yttrium, lithium, gadolinium, ytterbium, ruthenium, manganese, and alloys thereof are used. In organic electroluminescent devices,
At least the anode (1) or the cathode (2) is a transparent electrode so that light emission can be seen. At this time, if a transparent electrode is used as the cathode, transparency is likely to be impaired, so it is preferable to use a transparent electrode as the anode. When forming a transparent electrode, a conductive material such as that described above may be used on a transparent substrate, and the electrode may be formed by vapor deposition, sputtering, or the like to ensure desired translucency. The transparent substrate is not particularly limited as long as it has appropriate strength, is not adversely affected by heat caused by vapor deposition, etc. during the production of electroluminescent elements, and is transparent. Examples of such substrates include glass substrates, transparent substrates, etc. It is also possible to use resins such as polyethylene, polypropylene, polyether sulfone, polyether ether ketone, etc. Commercial products such as ITO and NESA are known as glass substrates on which transparent electrodes are formed, and these may be used.

The charge transport layer (12) has the general formula [
It may be formed by vapor deposition of a distyryl compound represented by I], or it may be formed by spin coating a suitable resin solution of the distyryl 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 distyryl compound content is about 20 to 80% by weight based on the binder resin. So that
It may be formed to have a thickness of about 0.05 to 1.0 μm.

Charge transport layer (12) thus formed
An organic light emitting layer is formed thereon. As the organic light-emitting substance used in the organic light-emitting layer, known ones can be used, such as epidolizine, 2,5-bis[5,7-di-t-
Pentyl-2-benzoxazolyl]thiophene, 2,2
'-(1,4-phenylene divinylene)bisbenzothiazole, 2,2'-(4,4'-biphenylene)bisbenzothiazole, 5-methyl-2-{2-[4-(5-
Methyl-2-benzoxazolyl)phenyl]vinyl}benzoxazole, 2,5-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 bisoxine, bis(benzo-8-quinolinol)zinc, bis(
2-methyl-8quinolinolate) aluminum oxide, indium trisoxine, aluminum tris(
5-methyloxine), lithium oxine, gallium trioxin, calcium bis(5-chlorooxine),
Polyzinc-bis(8-hydroxy-5-quinolinonyl)
Methane) dilithium epindolidione, zinc bisoxine, 1,2-phthaloperinone, 1,2-naphthaloperinone, etc. can be mentioned. In addition, common fluorescent dyes such as fluorescent coumarin dyes, fluorescent perylene dyes, fluorescent pyran dyes, fluorescent thiopyran dyes, fluorescent polymethine dyes,
Fluorescent merocyanine dyes, fluorescent imidazole dyes, etc. can also be used. Among these, particularly preferred are chelated oxinoid compounds. The organic light emitting layer may have a single layer structure of the above-mentioned light emitting substance, or may have a multilayer structure in order to adjust characteristics such as the color of the emitted light and the intensity of the emitted light. Next, the above-described cathode is formed on the organic light emitting layer.

As described above, the charge transport layer (12) is formed on the anode (11).
), a light emitting layer (13) and a cathode (14) are sequentially laminated to form an organic luminescent element.
2) and the anode may be sequentially laminated. One set of transparent electrodes is connected to each electrode with a suitable lead wire (15) such as nichrome wire, gold wire, copper wire, platinum wire, etc., and the organic luminescent element applies a suitable voltage (Vs) to both electrodes. It emits light. The organic electroluminescent device of the present invention can be applied to various display devices or display devices. The present invention will be described below with reference to specific examples. In the following examples, "parts" means "parts by weight" unless otherwise specified.

Synthesis example Synthesis example of compound [1] The following formula:

4.51 g (0.01 mol) of the aldehyde compound represented by the formula and 2.28 g (0.01 mol) of diethyl benzylphosphonate
mol) was added to 50 ml of dimethylformamide (DMF) and dissolved. While cooling the resulting solution to 50C, a suspension containing 1.68 g of potassium t-butoxide in 50 ml of dimethylformamide was added dropwise to the solution. The resulting solution was stirred at room temperature for 4 hours and then treated at 800C for 2 hours to complete the reaction. The resulting mixture was added to 500 ml of water and neutralized with dilute hydrochloric acid. After 30 minutes, the precipitated crystals were filtered. The filtered product was washed with water, dissolved in toluene, and separated and purified using silica gel column chromatography. After distilling off toluene from the effluent, it was recrystallized from ethanol to obtain 3.8 g (yield 72.4%) of pale yellow crystals. The melting point was 76-780C. The results of elemental analysis are as follows (as C40H31N).

[0034]

[Table 1]
Table 1 ──────────
────────────
C (%) H (%)
N (%) ────────────
────────── Calculated value 91.43 5.90
2.67 ──────────
──────────── Experimental value 91.40 5.85
2.75 ─────
──────────────────

The infrared absorption spectrum (KBr tablet method) of the product is shown in FIG. In addition, the infrared absorption spectrum is model 1710FTI
R (manufactured by PerkinElmer), resolution 4cm-
1. Measurement was performed under conditions of 5 scans.

Synthesis Examples 2 to 17 The methods of the present invention were carried out in the same manner as in Synthesis Example 1, except that the aldehyde compounds and phosphorus compounds shown in Tables 2 to 5 were used in place of the aldehyde compounds and phosphorus compounds used in Synthesis Example 1. A distyryl compound was synthesized. The table shows the melting point, recrystallization solvent, and elemental analysis results of each product. Also compounds [2], [4], [9], [21], [23], [24
], [27], and [39], infrared absorption spectra are shown in FIGS. 8 to 15, respectively.

[0037]

[Table 2]

[0038]

[Table 3]

[0039]

[Table 4]

[0040]

[Table 5]

Application of functionally separated photoreceptor to charge transport material Application example 1 A bisazo compound represented by the following general formula [A] as a charge generating substance:

embedded image 1 part of polyvinyl butyral resin (BM-2; manufactured by Sekisui Chemical Co., Ltd.) was dispersed in a sand mill with 50 parts of cyclohexanone and 30 parts of tetrahydrofuran. The resulting bisazo compound dispersion was applied onto an aluminum drum to a dry film thickness of 0.2 μm, and then dried.

On the charge generation layer thus obtained, 2 parts of distyryl compound [2] as a charge transport substance and 2 parts of polycarbonate resin (Panlite K-1300; manufactured by Teijin Chemicals) were added to 16 parts of tetrahydrofuran. The mixed and dissolved solution was applied to a dry film thickness of 20 μm,
It was dried to form a charge transport layer. In this way, 2
An electrophotographic photoreceptor having a photosensitive layer consisting of layers was obtained. This photoconductor has photoconductor No. Add 1.

Application Examples 2 to 8 Photoreceptors were produced in the same manner as in Application Example 1, except that distyryl compounds shown in Table 6 below were used in place of distyryl compound [2] in Application Example 1. Each of the photoreceptors obtained in these application examples was coated with photoreceptor No. Give 2 to 8.

[0044]

[Table 6]
Table 6------------
------------------- Photoreceptor N
o. 2 3 4
5 6 7 8
−−−−−−−−−−−−−−−−−−−−−−
--------------Distyryl [3]
[9] [15] [21] [23]
[30] [39] Compound No. −−−−−−−−−−−−−−−−−−−−−−−−−
−−−−−−−−−−

Comparative Examples 1 to 4 Application Example 1 except that the charge transport substances shown in Table 7 below were used in place of the distyryl compound [2] in Application Example 1.
A photoreceptor was produced in the same manner as described above. The photoreceptors obtained in these comparative examples were designated as photoreceptor No. Assign 9 to 11.

[0046]

[Table 7]

Photoreceptor No. thus obtained. 1 to 12 are commercially available electrostatic copying machines (manufactured by Minolta Camera Co., Ltd.; EP-47
0Z), corona charged at -6KV, initial surface potential V0 (V), exposure amount E1/2 (lux sec) required to reduce the initial potential to 1/2, and left in the dark for 1 second. The attenuation rate DDR1 (%) of the initial potential was measured. The measurement results are summarized in Table 8.

[0048]

[Table 8]
Table 8 ----------
−−−−−−−−−−−−−−−−−−− Photoreceptor No. V0 (V) E1/2 (lux・
sec) DDR1 (%) --------
−−−−−−−−−−−−−−−−−−−−−−−−−
-1 -650
0.8 3.0
2 -650
0.6 3.1
3 -640 0.5
3.4 4
-650 0.7
2.9 5
-650 0.6
3.0 6
-650 0.5
3.2 7
-660 0.6
2.7 8 -65
0 0.7 2
．． 9 9 -650
5.6 3.0
10 -660
3.2 2.5 1
1 -650 1.8
3.1 12
-650 3.5
2.9 ------------------------
−−−−−−−−−−−−−−−−−−−−−

004
9] As is clear from the above, by applying the distyryl compound of the present invention to a charge transport material for a photoreceptor, it has sufficient charge retention ability in both a laminated type and a single layer type, and the dark decay rate is sufficient for use as a photoreceptor. It is possible to obtain a photoreceptor that is as small as possible and also has excellent sensitivity.

Application of electroluminescent device to charge transport material Application example 9 A thin film with a thickness of 500 Å was formed by vapor deposition of distyryl compound [2] on glass coated with indium tin oxide. Next, aluminum trisoxine was deposited to a thickness of 500 Å.
A thin film was formed to have a thickness of . Next, a thin film with a thickness of 2000 Å was formed as a cathode using Mg and Ag at an atomic ratio of 10:1. In this way, an organic electroluminescent device was produced.

Application Examples 10 to 15 In Application Example 9, instead of using distyryl compound [2], distyryl compounds [3], [9], [15]
, [21], [23], and [30], an organic electroluminescent device was produced in exactly the same manner as in Application Example 1 except that the values were changed to [21], [23], and [30].

Comparative Examples 5 to 7 In Application Example 9, an organic electroluminescent device was produced in exactly the same manner as in Example 1 except that the following compound was used instead of distyryl compound [2]. (Comparative Example 5): N-ethylcarbazole-3-carbaldehyde-N-methyl, N-phenylhydrazone (Comparative Example 6): 2,5-bis(p-diethylaminophenyl)
-1,3,4-oxadiazole (Comparative Example 7): N,N,N-tri(p-tolyl)amine

Evaluation The electroluminescent device obtained in Application Example 9 was operated for 1 hour at a current density of 5 mA/cm 2 while applying a bias voltage using the glass electrode as an anode. Initial output is 0.1mW/cm2 to 0.095mW/c
m2. After operating for another hour, 0.09
It decreased to 0 mW/cm2. Similarly, application example 10~
Operation tests were conducted on the electroluminescent devices of Comparative Examples 12 and 5 to 7. The results are shown in Table 9.

[0054]

[Table 9]

According to the present invention, by incorporating a specific distyryl compound into the charge transport layer, it is possible to obtain an organic electroluminescent device with high emission intensity and excellent durability.

[0056]

[Effects of the Invention] The present invention provides a novel distyryl compound. The distyryl compound provided by the present invention can be used in charge transport layers of photoreceptors and electroluminescent devices. A photoreceptor in which the distyryl compound of the present invention is applied to the charge transport layer has excellent photoreceptor characteristics such as sensitivity, charge transportability, initial surface potential, and dark decay rate, and has little optical fatigue due to repeated use.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of a dispersion type photoreceptor comprising a photosensitive layer laminated on a conductive support.

FIG. 2 is a schematic diagram of a functionally separated photoreceptor in which a charge generation layer and a charge transport layer are laminated on a conductive support.

FIG. 3 is a schematic diagram of a functionally separated photoreceptor 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 photoreceptor in which a photosensitive layer and a surface protective layer are formed on a conductive support.

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

FIG. 6 represents a schematic cross-sectional view of an electroluminescent device.

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

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

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

FIG. 10 is a diagram showing an infrared absorption spectrum of an example of a distyryl compound of the present invention.

FIG. 11 is a diagram showing an infrared absorption spectrum of an example of a distyryl compound of the present invention.

FIG. 12 is a diagram showing an infrared absorption spectrum of an example of a distyryl compound of the present invention.

FIG. 13 is a diagram showing an infrared absorption spectrum of an example of a distyryl compound of the present invention.

FIG. 14 is a diagram showing an infrared absorption spectrum of an example of a distyryl compound of the present invention.

FIG. 15 is a diagram showing an infrared absorption spectrum of an example of a distyryl compound of the present invention.

Claims (3)

[Claims] Claim 1: The following general formula [I]: [Formula, R1 represents an alkyl group or an aryl group which may have a substituent; R2 represents an alkyl group, an aralkyl group, or a substituent-bearing aryl group; R3 is an alkyl group, a vinyl group, an ethynyl group, a benzyl group, an aryl group which may have a substituent, a furyl group, a thienyl group, an alkoxy group, an aralkyloxy group, a phenoxy group, a thioalkyl group. represents a group, thioaralkyl or thiophenyl group. ] A distyryl compound represented by. [Claim 2] A phosphorus represented by the following general formula [II]: [Formula 2] [wherein, R1 has the same meaning as R1 in the general formula [I] of claim 1, and R4 represents a lower alkyl group] Compound and the following general formula [III]: [Formula 3] [In the formula, R2 and R3 have the same meanings as R2 and R3 in the general formula [I] of claim 1. ] The following general formula [I] is characterized by reacting with an aldehyde compound represented by
: [Chemical formula 4] A method for producing a distyryl compound represented by: [Claim 3] The following general formula [IV] or [V]: [
[In the formula, R3 has the same meaning as R3 in the general formula [I] of claim 1; R5 represents a lower alkyl group. ] [C6
] [Wherein, R3 has the same meaning as R3 in the general formula [I] of claim 1; X represents a halogen atom] and the following general formula [VI]: [Chem. 7] In the formula, R1 and R2 have the same meanings as R1 and R2 in the general formula [I] of claim 1. ] The following general formula [I] is characterized by reacting with an aldehyde compound represented by
: [Chemical formula 8] A method for producing a distyryl compound represented by: