JP2000268963A - Organic electroluminescent element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an organic electroluminescent(EL) element of high fluorescent intensity, high resistance to electrons and holes and carrier trap capability capable of attaining light emittance of sufficient brightness and long wavelength in particular due to recombination probability of electrons with holes and of holding excellent light emitting performance. SOLUTION: This organic EL element has positive and negative electrodes and one kind or more of organic compound layers disposed between these electrodes. At least one layer or preferably a luminous layer of these organic compound layers contains a compound expressed by a formula. In the formula, respective R1-R6 represent any one of an aryl group, alkyl group, amino group or hydrogen atom. At least one of R1-R3 is the aryl group, at least one of R4-R6 is an aryl group and respective R7-R10 express any one of an aryl group, alkyl group, alkenyl group, alkoxy group, aryloxy group or hydrogen atom.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an organic EL (electroluminescence) element.

[0002]

2. Description of the Related Art An organic EL device has a structure in which a thin film containing a fluorescent organic compound is sandwiched between a cathode and an anode, and electrons and holes are injected into the thin film and recombined to form excitons (exciton). ), And emits light by utilizing light emission (fluorescence / phosphorescence) when the exciton is deactivated.

[0003] The organic EL element can operate at a low voltage of 10 V or less.
Surface emission with a high luminance of about 100 to 100,000 cd / m ² is possible. Further, by selecting the type of the fluorescent substance, light emission from blue to red is possible.

[0004] A doping method is known as a technique for obtaining an arbitrary luminescent color in an EL element, and a report has been made that the luminescent color is changed from blue to green by doping a small amount of tetracene into an anthracene crystal (Jpn. J. Appl. . Phys., 10,527 (197
1)) Further, in an organic thin film EL element having a stacked structure, a light emitting layer is formed by mixing a small amount of a fluorescent dye which emits light of a color different from that of the host material in response to the light emission into a host material having a light emitting function as a dopant. Report that the emission color is changed from green to orange to red
64692).

For long-wavelength light emission from yellow to red, a laser dye (EPO 281381) that emits red light, a compound showing exciplex light emission (JP-A-2-255788), a perylene compound (e.g. JP-A-3-791), coumarin compounds (JP-A-3-792), dicyanomethylene compounds (JP-A-3-162481), thioxanthene compounds (JP-A-3-177486), conjugated compounds A mixture of a polymer and an electron transporting compound (JP-A-6-73374), a squarylium compound (JP-A-6-93257), an oxadiazole-based compound (JP-A-6-136359), and an oxynate derivative (JP-A-6-136359) JP-A-6-145146), pyrene-based compounds (JP-A-6-24024) JP) there is.

As other light emitting materials, condensed polycyclic aromatic compounds (JP-A-5-32966, JP-A-5-2143)
No. 34) is also disclosed. Also, various condensed polycyclic aromatic compounds (Japanese Patent Laid-Open No.
No. 8859).

[0007] However, no sufficient luminance or stable light emission performance is obtained in any of the light emission. In general, a coumarin compound used as a dopant that changes emitted light to green is very weak to heat, and may not emit light due to heat generated at the time of forming a light emitting layer or driving. In addition, the stability in the state where the carrier is injected, that is, the electrochemical radical ion state is low,
The resistance to radiation such as an electron beam is low, and the fluorescence is reduced due to hydrolysis by water and particularly ionic components such as acids and alkalis. Further, further improvement in luminance or durability of the dopant material is desired. In particular, it is desired to increase the fluorescence intensity, increase the recombination probability of electrons and holes, and increase the generation probability of singlet excitons.

[0008]

The main objects of the present invention are to have a high fluorescence intensity, a high resistance to electrons and holes, a high carrier trapping property, and a high recombination probability of electrons and holes. It is an object of the present invention to provide an organic EL device which emits light of sufficient luminance, in particular, emits light of a long wavelength, and has excellent durability in which good light emitting performance is maintained for a long period of time.

[0009]

This and other objects are achieved by the present invention described below. (1) An anode, a cathode, and at least one organic compound layer provided between these electrodes, wherein at least one of the organic compound layers is a compound represented by the following general formula (I) An organic EL device containing:

[0010]

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(In the general formula (I), R _{1 to} R ₆ each represent an aryl group, an alkyl group, an amino group or a hydrogen atom, at least one of R _{1 to} R ₃ is an aryl group, ₄ at least one is an aryl group to R _6, R ₇ to R ₁₀ are each an aryl group, an alkyl group, an alkenyl group, an alkoxy group, and an aryloxy group or a hydrogen atom.) (2) the organic compound The organic EL device according to the above (1), wherein at least one of the layers is a light emitting layer, and the light emitting layer contains the compound represented by the general formula (I). (3) The organic EL device according to (1) or (2), wherein the compound represented by the general formula (I) is a dopant of a host substance having a light emitting function by itself. (4) The organic EL device according to (3), wherein the host substance is a triarylamine derivative. (5) The organic EL device according to (3), wherein the host substance is a quinolinol derivative. (6) The light emitting layer is a mixed layer of at least one or more hole injecting and transporting compounds and at least one or more electron injecting and transporting compounds, and the compound represented by the general formula (I) is: The organic EL device according to any one of (2) to (5), which is a dopant of the mixed layer having a light emitting function. (7) The organic EL device according to (6), wherein the hole injecting and transporting compound is a tetraaryl arylenediamine derivative and / or a triarylamine derivative, and the electron injecting and transporting compound is a quinolinol derivative.

[0012]

The organic EL device of the present invention has an anode, a cathode, and one or more organic compound layers provided between these electrodes, and at least one organic compound layer, preferably a light emitting layer, is provided. And a compound represented by the above general formula (I).
Therefore, a wavelength range of about 460 to 600 nm, especially 520
It has a maximum emission wavelength in the green emission region around nm. In particular, the compound of the general formula (I) has a light-emitting function in a light-emitting layer formed as a dopant of a host substance having a light-emitting function by itself, or formed of an electron injecting and transporting compound and a hole injecting and transporting compound. By using the mixed layer as a dopant, blue to red light emission, particularly long wavelength light emission, can be obtained, sufficient luminance can be obtained, and good light emission performance can be maintained for a long time.

The present inventors have disclosed in Japanese Patent Application Laid-Open No. H8-3114.
No. 42, a double bond-containing group represented by the general formula (I)

[0014]

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Instead of the above, a compound having an aryl group has been proposed, but the compound of the general formula (I) is superior to this in terms of luminance. In particular, it is a highly efficient material with small concentration quenching of fluorescence in a high concentration region.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a specific configuration of the present invention will be described. <Compound of the Present Invention> In the organic EL device of the present invention, at least one organic compound layer, preferably a light emitting layer, contains the compound represented by the above general formula (I). This organic EL device has a maximum emission wavelength in a wavelength range of about 460 to 600 nm, particularly in a green emission range around 520 nm. In particular, the compound of the general formula (I) is used as a dopant of a host substance having a light emitting function by itself in the light emitting layer, or
By using as a dopant of a mixed layer having a light emitting function formed of an electron injecting and transporting compound and a hole injecting and transporting compound, blue to red light emission, particularly long wavelength light emission, is possible, and sufficient Brightness is obtained, and light emission performance is maintained.

In the general formula (I), R _{1 to} R ₆ each represent any one of an aryl group, an alkyl group, an amino group and a hydrogen atom.

The aryl group may be monocyclic or polycyclic, and may be phenyl, biphenyl, terphenyl, alkylphenyl, alkoxyphenyl,
Examples thereof include an arylphenyl group, an aryloxyphenyl group, an alkenylphenyl group, an aminophenyl group, a naphthyl group, an anthryl group, a pyrenyl group, and a perylenyl group. The non-monovalent residue of the condensed polycyclic aromatic group may further have a substituent, but is generally preferably unsubstituted.

The alkylphenyl group preferably has 1 to 10, more preferably 1 to 6, and particularly preferably 1 to 4 carbon atoms in the alkyl portion. The alkyl group is branched even if it is linear. It may be something. Methyl group, ethyl group, (n, i) -propyl group, (n, i, sec, t
ert) -butyl group, (n, i, neo, tert)-
Examples include an alkyl group such as a pentyl group and a (n, i, neo) -hexyl group. The substitution position of these alkyl groups in the phenyl group may be any of the o, m, and p positions. Specific examples of such an alkylphenyl group include:
(O, m, p) -tolyl group, 4-n-butylphenyl group, 4-t-butylphenyl group and the like.

The alkoxyphenyl group preferably has 1 to 10 carbon atoms in the alkyl portion, and the carbon chain of the alkoxy group may be linear or branched. Methoxy, ethoxy, (n, i) -propoxy, (n, i, sec, tert) -butoxy, (n, i, neo, tert) -pentyloxy, (n, i, neo)- An alkoxy group such as a hexyloxy group is exemplified. The substitution position of these alkoxy groups in the phenyl group may be any of the o, m and p positions. Specific examples of such an alkoxyphenyl group include (o, m, p) -methoxyphenyl group, p-butoxyphenyl group, p-ethoxyphenyl group, p-isopropylphenyl group, p-hexylphenyl group and the like. Can be

As the arylphenyl group, those in which the aryl moiety is a phenyl group are preferred. Such a phenyl group may be substituted, and the substituent at this time is preferably an alkyl group. Specific examples include the alkyl groups exemplified above for the alkylphenyl group. Further, the aryl moiety may be a phenyl group substituted by an aryl group such as a phenyl group. Specific examples of such an arylphenyl group include (o,
m, p) -biphenylyl group, 4-tolylphenyl group, 3
-Tolylphenyl group, terephenylyl group and the like.

As the aryloxyphenyl group, those in which the aryl moiety is a phenyl group are preferred. Such a phenyl group may be substituted, and the substituent at this time is preferably the above-mentioned alkyl group. Further, the aryl moiety may be a phenyl group substituted by an aryl group such as a phenyl group. Specific examples of such an aryloxyphenyl group include a phenoxyphenyl group, a biphenoxyphenyl group, a naphthoxyphenyl group, and the like.

The alkenylphenyl group is preferably one having a total of 2 to 20 carbon atoms in the alkenyl portion, and the alkenyl group is preferably a triarylalkenyl group or a diarylalkenyl group, for example, a triphenylvinyl group, a tolylvinyl group, Examples include a tribiphenylvinyl group, a diphenylvinyl group, a ditolylvinyl group, and a dibiphenylvinyl group. Specific examples of such an alkenylphenyl group include a triphenylvinylphenyl group.

The aminophenyl group preferably has an amino moiety as a diarylamino group. Examples of the diarylamino group include a diphenylamino group and a phenyltolylamino group.

As the naphthyl group, 1-naphthyl group, 2
-A naphthyl group or the like.

The anthryl group may be a 1-anthryl group, a 2-anthryl group, a 9-anthryl group or the like.

As the pyrenyl group, 1-pyrenyl group, 2
-A pyrenyl group or the like.

The perylenyl group may be a 1-perylenyl group, a 2-perylenyl group or the like.

As the aryl group, among the above, a phenyl group, a biphenylyl group, a naphthyl group, an unsubstituted phenyl group and a biphenylyl group are particularly preferable.

The alkyl group has 1 to 12 carbon atoms, more preferably 1 to 6 carbon atoms, and especially 1 to 6 carbon atoms.
It is preferably four, and may be linear or branched, and specifically, a methyl group, an ethyl group, a (n, i) -propyl group, a (n, i, sec, te
rt) -butyl group and the like are preferred.

As the amino group, a substituted amino group is preferable, and a disubstituted product of the above-mentioned alkyl group and / or aryl group, particularly a diarylamino group such as a diphenylamino group and a phenyltolylamino group is preferable.

R _{1 to} R ₆ may be the same or different.
Further, at least one of R _{1 to} R ₃ is an aryl group,
Moreover, at least one of R _{4 to} R ₆ is an aryl group. In this case, it is preferable that at least R ₂ and R ₅ are aryl groups. The number of aryl groups among R _{1 to} R ₃ and R _{4 to} R ₆ is preferably 1 to 3, and more preferably 2 to 3.

R _{7 to} R ₁₀ each represent any of an aryl group, an alkyl group, an alkenyl group, an alkoxy group, an aryloxy group and a hydrogen atom.

As the aryl group and the alkyl group, the same groups as those described above for R _{1 to} R ₆ can be mentioned, and preferred ones are also the same.

The alkenyl group is preferably a triarylalkenyl group or a diarylalkenyl group, for example, a triphenylvinyl group, a tolylvinyl group, a tribiphenylvinyl group, a diphenylvinyl group, a ditolylvinyl group, a dibiphenylvinyl group and the like. . The alkenyl group preferably has 6 to 50 carbon atoms in total, and may be unsubstituted or substituted.

The alkoxy group preferably has 1 to 6 carbon atoms in the alkyl group, and specific examples include a methoxy group, an ethoxy group and a t-butoxy group. The alkoxy group may be further substituted.

As the aryloxy group, a phenoxy group,
Examples include a biphenyloxy group, a naphthyloxy group, a pyrenyloxy group, a perylenyloxy group, and the like. The aryloxy group may be further substituted.

R _{7 to} R ₁₀ may be the same or different. Preferably, at least two R ₇ to R ₁₀ is a hydrogen atom, and more preferably all are hydrogen atoms.

In the general formula (I), two phenyl groups bonded to the 5- and 12-positions of naphthacene have a double bond-containing group.

[0040]

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Although high properties can be obtained with respect to naphthacene even when bonded to the o-position and m-position, those bonded to the p-position have higher luminance and longer half-life of luminance. Become.

Hereinafter, specific examples of the compound represented by formula (I) will be shown, but the present invention is not limited to these. In addition, chemical formula 5, chemical formula 6, chemical formula 7, chemical formula 8, chemical formula 9, chemical formula 10,
Chemical formula 11 is shown using the general formula (I) of Chemical formula 1.

[0043]

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[0044]

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[0045]

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[0046]

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[0047]

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[0048]

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[0049]

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The compounds of the general formula (I) may be used alone or in combination of two or more.

<Content of Compound of the Present Invention as a Dopant> The content of the compound of the general formula (I) in the light emitting layer is preferably at least 0.01 wt%, more preferably at least 0.1 wt%.

In particular, the compound of the formula (I) is preferably used in combination with a host substance, particularly a host substance capable of emitting light by itself, and is preferably used as a dopant. In such a case, the content of the compound of the general formula (I) in the light emitting layer is preferably 0.01 to 20% by weight, more preferably 0.1 to 15% by weight. When used in combination with a host substance, the emission wavelength characteristics of the host substance can be changed, light emission of a long wavelength becomes possible, and the luminous efficiency and stability of the device are improved.

<Method of synthesizing compound of the present invention> The compound represented by the general formula (I) is prepared by reacting an aromatic compound having a quinone structure with a Grignard reagent or a lithiation reagent and further reducing the compound (Maulding, DR, et al., J. Org. Che
m., 34 , 1734 (1969) and Hanhela, PJ, et al., Aust.
J. Chem., 34 , 1687 (1981)) or according to this method. The following are synthesis examples.

[Synthesis Example 1] 5,12-bis [-4- (2-phenylethenyl) phenyl
Synthesis of phenyl] naphthacene It was synthesized according to the following formula (A).

[0055]

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In a flask purged with argon, 4.0 g of 4-bromostilbene, 20 ml of toluene and 20 ml of diethyl ether were added and stirred. Here, 1.6 mol / l of n
9.4 ml of a hexane solution of -butyllithium was added, and 30
After stirring for 4 minutes, 4-lithiostilbene was prepared. The prepared lithium solution was slowly added to another container containing 1.4 g of naphthacenequinone, 30 ml of toluene, and 30 ml of diethyl ether. After stirring until the reaction was completed, the mixture was hydrolyzed, extracted with toluene, dried over magnesium sulfate, and the solvent was distilled off. The residue was purified by column and reprecipitation (acetone-hexane) to obtain 2.0 g of a white diol.

2.0 g of this white diol was added to 300 ml
Into an eggplant flask, and add tetrahydrofuran (THF)
50 ml, 4.0 g of tin chloride and 50 ml of hydrochloric acid were added and stirred for about 1 hour. After extraction with toluene, the organic layer was washed well with water, and the solvent was distilled off. After passing through a silica gel column, reprecipitation (chloroform-hexane) was performed three times to obtain 1.6 g of an orange solid. This orange solid was purified by sublimation to obtain 1.4 g of a fluorescent target substance.

[Synthesis Example 2] 5,12-bis [-4- (2,2-diphenylethenyl)
L) Phenyl] naphthacene was synthesized according to the following formula (B).

[0059]

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5.0 g of 1- (4-bromophenyl) -2,2-diphenylethylene was placed in a flask purged with argon.
And 20 ml of toluene and 20 ml of diethyl ether.
Stirred. To this, 9.0 ml of a 1.6 mol / l n-butyllithium hexane solution was added and stirred for 30 minutes to prepare a lithium reagent. The prepared lithium reagent was
-Slowly added to another vessel containing 1.3 g of naphthacenequinone, 30 ml of toluene and 30 ml of diethyl ether. After stirring until the reaction was completed, the mixture was hydrolyzed, extracted with toluene, dried over magnesium sulfate, and the solvent was distilled off. The residue was passed through a column and reprecipitated (acetone-hexane) three times to obtain 3.3 g of a white diol.

The white diol compound (3.0 g) was added to 300 ml.
Into 50 ml of THF, 50 ml of THF, tin (II) chloride
5.0 g and 50 ml of hydrochloric acid were added and stirred for about 1 hour. After extraction with toluene, the organic layer was washed well with water, and the solvent was distilled off. After passing through a silica gel column, reprecipitation (chloroform-hexane) was performed three times to obtain 2.2 g of an orange solid.
I got This orange solid is purified by sublimation and 2.0 g
This yielded an orange fluorescent target product.

[Synthesis Example 3] 5,12-bis [-4- (2,2,1-triphenyle
Synthesis of [tenyl) phenyl] naphthacene It was synthesized according to the following formula (C).

[0063]

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In a flask purged with argon, 5.0 g of 1,4-dibromobenzene, 20 ml of toluene and 20 ml of diethyl ether were added and stirred. Here, 1.6 mol / l
12 ml of a hexane solution of n-butyllithium
The mixture was stirred for 0 minutes to prepare 4-bromophenyllithium.
The prepared 4-bromophenyllithium was slowly added to another container containing 1.8 g of 5,12-naphthacenequinone, 30 ml of toluene, and 30 ml of diethyl ether.
After stirring until the reaction was completed, the mixture was hydrolyzed, extracted with toluene, dried with calcium chloride, and the solvent was distilled off. The obtained solid is recrystallized with an acetone-hexane mixed solvent,
2.9 g of a white solid diol was obtained.

The white diol was placed in a 300 ml eggplant-shaped flask, and 50 ml of THF and 5.0 g of tin (II) chloride were added.
And 50 ml of hydrochloric acid, and the mixture was stirred for about 1 hour. After extraction with toluene, the organic layer was washed well with water, and the solvent was distilled off. After passing through a silica gel column, reprecipitation (chloroform-hexane) gave 2.1 g of 5,12-bis (4-bromophenyl) naphthacene as an orange solid.

A flask equipped with a reflux tube and a dropping funnel was charged with 0.36 g of magnesium and 50 ml of THF, and a solution of 5.0 g of 1,1,2-triphenyl-2-bromoethylene dissolved in 20 ml of THF was dropped from the dropping funnel. I do.
After completion of the dropwise addition, the mixture was stirred with heating for about 1 hour to prepare a Grignard reagent. In a separate container, 2.0 g of the orange solid obtained above, 0.40 g of diphenylphosphinoethane nickel chloride and 50 ml of THF were added, and the Grignard reagent was slowly added thereto. This solution was heated and stirred until the reaction was completed. Thereafter, the product was hydrolyzed, extracted with toluene, passed through a column, and reprecipitated to obtain 1.5 g of the desired product as an orange solid.

[Synthesis Example 4] 5,12-bis [-4- (4-phenyl-1,4-buta)
Synthesis of [dienyl) phenyl] naphthacene was synthesized according to the following formula (D).

[0068]

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In a flask purged with argon, 10 g of 4-bromotoluene, 25 ml of toluene, and 25 ml of diethyl ether
ml and stirred. 35 ml of a 1.6 mol / l n-butyllithium hexane solution was added thereto, followed by stirring for 30 minutes to prepare 4-lithiotoluene. The prepared 4-lithiotoluene was slowly added to another container containing 4.8 g of 5,12-naphthacenequinone, 50 ml of toluene, and 50 ml of diethyl ether. After stirring until the reaction was completed, the mixture was hydrolyzed, extracted with toluene, dried over magnesium sulfate, and the solvent was distilled off. The residue was purified by column and reprecipitation (acetone-hexane) to obtain 6.6 g of a diol as a white solid.

6.5 g of this white solid was placed in a 300 ml eggplant flask, and 50 ml of THF, 10 g of tin (II) chloride,
50 ml of hydrochloric acid was added and stirred for about 1 hour. After extraction with toluene, the organic layer was washed well with water, and the solvent was distilled off. After passing through a silica gel column, reprecipitation (chloroform-hexane) gave 5,12-bis (4) as an orange solid.
5.0 g of (-methylphenyl) naphthacene were obtained.

To 5.0 g of this orange solid was added 2.1 g of N-bromosuccinimide, and the mixture was heated and refluxed for 3 hours in carbon tetrachloride. Filtering the insoluble succinimide,
The product was separated by a column to obtain 5.9 g of bis (4-bromomethylphenyl) naphthacene.

To 5.8 g of bis (4-bromomethylphenyl) naphthacene was added 4.1 g of triethyl phosphite, and the mixture was heated and stirred. Upon cooling of the reaction, the desired product solidifies. This was filtered, recrystallized and purified by column to obtain 6.0 g of phosphoric ester.

3.0 g of phosphate ester, 1.4 g of trans-cinnamaldehyde, T
10 ml of HF was added and stirred. 20 ml of a THF solution of potassium t-butoxide (concentration: 1.0 mol / l) was slowly added dropwise at room temperature. After stirring overnight, hydrolyze,
After extraction with toluene and drying over magnesium sulfate, the solvent was distilled off. Purification by column and recrystallization gave 2.0 g of the desired product.

[Synthesis Example 5] 5,12-bis {-4-[-2- (N, N-dimethyl-
Synthesis of 4-aminophenyl) etheniyl] {naphthacene It was synthesized according to the following formula (E).

[0075]

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In a flask purged with argon, 3.0 g of the phosphoric ester obtained in Synthesis Example 4, 1.6 g of 4- (N, N-dimethylamino) benzaldehyde and 10 ml of THF were placed.
And stirred. Here, the T of potassium t-butoxide
20 ml of an HF solution (concentration: 1.0 mol / l) was slowly added dropwise at room temperature. After stirring overnight, the mixture was hydrolyzed, extracted with toluene, dried over magnesium sulfate, and the solvent was distilled off. The residue was purified by column and recrystallization to obtain 2.0 g of the target compound substituted with dimethylamino.

[Synthesis Example 6] 5,12-bis {-4-[-2- (N, N-diphenyl)
-4-aminophenyl) etheniyl]
The compound was synthesized according to the following formula (F).

[0078]

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In a flask purged with argon, 3.0 g of the phosphate ester obtained in Synthesis Example 4, 1.6 g of 4- (N, N-diphenylamino) benzaldehyde, THF10
ml was added and stirred. 20 ml of a THF solution of potassium t-butoxide (concentration: 1.0 mol / l) was slowly added dropwise at room temperature. After stirring overnight, the mixture was hydrolyzed, extracted with toluene, dried over magnesium sulfate, and the solvent was distilled off. Purification by column and recrystallization gave 2.0 g of the desired product.

The compound of the present invention can be identified by mass spectrometry, infrared absorption spectrum (IR), ¹ H, ¹³ C nuclear magnetic resonance spectrum (NMR) and the like. As an example, FIG. 1 shows a Mass (mass spectrometry) spectrum of 5,12-bis [-4- (2-phenylethenyl) phenyl] naphthacene (No. 2 of Chemical Formula 5), and FIG. 2 shows a ¹ H-NMR spectrum thereof. FIG. 3 shows the ¹³ C-NMR spectrum and FIG. 4 shows the IR spectrum.

<Structural Example of Organic EL Element>
FIG. 5 shows an example of the configuration of the L element.
The organic EL device shown in FIG.
It has a hole injection transport layer 3, a light emitting layer 4, an electron injection transport layer 5, and a cathode 6 in that order. Depending on the function of the light emitting layer, the hole injection transport layer 3 and / or the electron injection transport layer 5 can be omitted.

<Light Emitting Layer, Hole Injecting / Transporting Layer, Electron Injecting / Transporting Layer> The light emitting layer has a hole (hole) and electron injecting function,
They have a transport function and a function of generating excitons by recombination of holes and electrons. It is preferable to use a relatively electronically neutral compound for the light emitting layer, that is, a compound that can stably and easily inject electrons and holes. Further, the recombination efficiency is maximized in order to improve the luminous efficiency of the light emitting layer, but it is important to provide a carrier trapping property to such an extent that the driving voltage of the element does not increase.

The hole injecting / transporting layer has a function of facilitating hole injection from the anode, a function of transporting holes, and a function of hindering electrons. The electron injecting / transporting layer has a function of injecting electrons from the cathode. , A function of transporting electrons, and a function of blocking holes. These layers increase and confine holes and electrons injected into the light emitting layer, optimize the recombination region, and improve luminous efficiency. The hole injecting / transporting layer and the electron injecting / transporting layer are provided as necessary in consideration of the height of the functions of the compound used in the light emitting layer for hole injection, hole transport, electron injection, and electron transport. For example, when the compound used for the light-emitting layer has a high hole-injection-transport function or an electron-injection-transport function, the light-emitting layer may be provided without the hole-injection-transport layer or the electron-injection-transport layer. It can be configured to also serve as a transport layer. In some cases, neither the hole injection transport layer nor the electron injection transport layer may be provided. In addition, the hole injection / transport layer and the electron injection / transport layer may be separately provided in a layer having an injection function and a layer having a transport function.

The thickness of the light emitting layer, the thickness of the hole injecting and transporting layer, and the thickness of the electron injecting and transporting layer are not particularly limited, and vary depending on the design and formation method of the recombination region and the light emitting region. The thickness is preferably about 1000 nm, especially about 10 to 200 nm.

The thickness of the hole injecting / transporting layer and the thickness of the electron injecting / transporting layer depend on the design of the recombination / light emitting region, but may be about the same as the thickness of the light emitting layer or about 1/100 to 100 times. I just need. When separating the injection layer and the transport layer for each electron or hole, the injection layer is 1 nm or more and the transport layer is 20 nm.
It is preferable to make the above. At this time, the upper limit of the thickness of the injection layer and the transport layer is usually about 1000 nm for the injection layer and about 1000 nm for the transport layer. For such a film thickness,
The same applies when two injection / transport layers are provided.

Also, by controlling the film thickness in consideration of the carrier mobility and carrier density (determined by ionization potential and electron affinity) of the combined light emitting layer, electron injection transport layer and hole injection transport layer, the recombination region・
It is possible to freely design a light emitting region, and it is possible to design a light emitting color, control a light emission luminance and a light emission spectrum by an interference effect between both electrodes, and control a spatial distribution of light emission.

The compound of the general formula (I) is preferably used for a light emitting layer, and the organic compound layer containing the compound of the general formula (I) is preferably a light emitting layer.

<Host substance> By using the compound of the general formula (I) of the present invention in combination with a host substance, the emission wavelength characteristics of the host substance can be changed, and long-wavelength light emission becomes possible. At the same time, the luminous efficiency and stability of the device are improved. As the host substance, a triarylamine derivative described below is preferable.

As the host substance, a quinoline derivative is preferable, and more preferably, an aluminum complex having 8-quinolinol or a derivative thereof as a ligand. Such an aluminum complex is disclosed in JP-A-63-264.
No. 692, JP-A-3-255190, JP-A-5-70
733, JP-A-5-258859, JP-A-6-21
No. 5,874, for example.

Specifically, first, tris (8-quinolinolato) aluminum, bis (8-quinolinolato) magnesium, bis (benzo {f} -8-quinolinolato) zinc, bis (2-methyl-8-quinolinolato) aluminum Oxide, tris (8-quinolinolato) indium,
Tris (5-methyl-8-quinolinolato) aluminum, 8-quinolinolatolithium, tris (5-chloro-
8-quinolinolato) gallium, bis (5-chloro-8-
Quinolinolato) calcium, 5,7-dichloro-8-quinolinolatoaluminum, tris (5,7-dibromo-
8-hydroxyquinolinolato) aluminum and poly [zinc (II) -bis (8-hydroxy-5-quinolinyl) methane].

In addition to 8-quinolinol or a derivative thereof, an aluminum complex having another ligand may be used, such as bis (2-methyl-
8-quinolinolato) (phenolato) aluminum (III)
, Bis (2-methyl-8-quinolinolato) (ortho-
Cresolato) aluminum (III), bis (2-methyl-
8-quinolinolato) (meth-cresolate) aluminum
(III), bis (2-methyl-8-quinolinolato) (para-cresolato) aluminum (III), bis (2-methyl-8-quinolinolato) (ortho-phenylphenolate)
Aluminum (III), bis (2-methyl-8-quinolinolato) (meth-phenylphenolato) aluminum (II
I), bis (2-methyl-8-quinolinolato) (para-
Phenylphenolato) aluminum (III), bis (2-
Methyl-8-quinolinolato) (2,3-dimethylphenolato) aluminum (III), bis (2-methyl-8-quinolinolato) (2,6-dimethylphenolato) aluminum (III), bis (2-methyl- 8-quinolinolato)
(3,4-dimethylphenolato) aluminum (III),
Bis (2-methyl-8-quinolinolato) (3,5-dimethylphenolato) aluminum (III), bis (2-methyl-8-quinolinolato) (3,5-di-tert-butylphenolato) aluminum (III) ), Bis (2-methyl-8)
-Quinolinolato) (2,6-diphenylphenolato) aluminum (III), bis (2-methyl-8-quinolinolato) (2,4,6-triphenylphenolato) aluminum (III), bis (2-methyl- 8-quinolinolato)
(2,3,6-trimethylphenolato) aluminum (I
II), bis (2-methyl-8-quinolinolato) (2,
3,5,6-tetramethylphenolato) aluminum (I
II), bis (2-methyl-8-quinolinolato) (1-naphthrat) aluminum (III), bis (2-methyl-8
-Quinolinolato) (2-naphthrat) aluminum (II
I), bis (2,4-dimethyl-8-quinolinolato)
(Ortho-phenylphenolato) aluminum (III),
Bis (2,4-dimethyl-8-quinolinolato) (para-
Phenylphenolato) aluminum (III), bis (2,
4-dimethyl-8-quinolinolato) (meta-phenylphenolato) aluminum (III), bis (2,4-dimethyl-8-quinolinolato) (3,5-dimethylphenolato) aluminum (III), bis (2 4-dimethyl-8
-Quinolinolato) (3,5-di-tert-butylphenolato) aluminum (III), bis (2-methyl-4-ethyl-8-quinolinolato) (para-cresolato) aluminum (III), bis (2-methyl) -4-methoxy-8-quinolinolato) (para-phenylphenolato) aluminum (III), bis (2-methyl-5-cyano-8-quinolinolato) (ortho-cresolato) aluminum (III),
Bis (2-methyl-6-trifluoromethyl-8-quinolinolato) (2-naphthrat) aluminum (III);

In addition, bis (2-methyl-8-quinolinolato) aluminum (III) -μ-oxo-bis (2-
Methyl-8-quinolinolato) aluminum (III), bis (2,4-dimethyl-8-quinolinolato) aluminum
(III) -μ-oxo-bis (2,4-dimethyl-8-quinolinolato) aluminum (III), bis (4-ethyl-
2-methyl-8-quinolinolato) aluminum (III)-
μ-oxo-bis (4-ethyl-2-methyl-8-quinolinolato) aluminum (III), bis (2-methyl-4
-Methoxyquinolinolato) aluminum (III) -μ-oxo-bis (2-methyl-4-methoxyquinolinolato)
Aluminum (III), bis (5-cyano-2-methyl-
8-quinolinolato) aluminum (III) -μ-oxo-
Bis (5-cyano-2-methyl-8-quinolinolato) aluminum (III), bis (2-methyl-5-trifluoromethyl-8-quinolinolato) aluminum (III) -μ
-Oxo-bis (2-methyl-5-trifluoromethyl-8-quinolinolato) aluminum (III) and the like.

Among these, in the present invention, it is particularly preferable to use tris (8-quinolinolato) aluminum (AlQ3).

Other host materials are disclosed in
Also preferred are phenylanthracene derivatives described in JP-A-012600 and tetraarylethene derivatives described in JP-A-8-012969.

The phenylanthracene derivative is represented by the following general formula (II). General formula (II) A ₁ −
LA- ₂

In the general formula (II), A ₁ and A
₂ represents a monophenylanthryl group or a diphenylanthryl group, which may be the same or different.

The monophenylanthryl group or diphenylanthryl group represented by A ₁ and A ₂ may be unsubstituted or have a substituent. When it has a substituent, examples of the substituent include an alkyl group, an aryl group, an alkoxy group, an aryloxy group, and an amino group, and these substituents may be further substituted. These substituents will be described later. Further, the substitution position of such a substituent is not particularly limited, but is not an anthracene ring,
It is preferably a phenyl group bonded to the anthracene ring.

Further, the bonding position of the phenyl group on the anthracene ring is preferably at the 9th and 10th positions of the anthracene ring.

In the formula (II), L represents a single bond or a divalent group, and the divalent group represented by L is preferably an arylene group optionally interposed with an alkylene group or the like. Such an arylene group will be described later.

Of the phenylanthracene derivatives represented by the formula (II), those represented by the following formulas (III) and (IV) are preferable.

[0101]

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[0102]

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In the formula (III), R ₀₁ and R ₀₂ are
Each represents an alkyl group, a cycloalkyl group, an aryl group, an alkoxy group, an aryloxy group, an amino group or a heterocyclic group.

The alkyl group represented by R ₀₁ and R ₀₂ may be linear or branched, and may be a substituted or unsubstituted alkyl having 1 to 10 carbon atoms, further having 1 to 4 carbon atoms. Groups are preferred. In particular, an unsubstituted alkyl group having 1 to 4 carbon atoms is preferable, and specifically, a methyl group, an ethyl group,
(N-, i-) propyl group, (n-, i-, s-, t
-) Butyl group and the like.

Examples of the cycloalkyl group represented by R ₀₁ and R ₀₂ include a cyclohexyl group and a cyclopentyl group.

The aryl group represented by R ₀₁ and R ₀₂ preferably has 6 to 20 carbon atoms, and may further have a substituent such as a phenyl group or a tolyl group. Specific examples include a phenyl group, an (o-, m-, p-) tolyl group, a pyrenyl group, a naphthyl group, an anthryl group, a biphenyl group, a phenylanthryl group, and a tolyl anthryl group.

The alkoxy group represented by R ₀₁ and R ₀₂ is preferably an alkoxy group having 1 to 6 carbon atoms in the alkyl group, and specific examples include a methoxy group and an ethoxy group. The alkoxy group may be further substituted.

Examples of the aryloxy group represented by R ₀₁ and R ₀₂ include a phenoxy group and the like.

The amino group represented by R ₀₁ and R ₀₂ may be unsubstituted or substituted, but preferably has a substituent. In this case, the substituent is preferably an alkyl group (methyl Group, an ethyl group, etc.) and an aryl group (a phenyl group, etc.). Specific examples include a diethylamino group and a diphenylamino group.

As the heterocyclic groups represented by R ₀₁ and R ₀₂ ,
Examples include a bipyridyl group, a pyrimidyl group, a quinolyl group, a pyridyl group, a thienyl group, a furyl group, and an oxadiazoyl group. These may have a substituent such as a methyl group or a phenyl group.

In the formula (III), r01 and r02
Represents 0 or an integer of 1 to 5, and preferably 0 or 1. r01 and r02 are each an integer of 1 to 5, when in particular 1 or 2, R ₀₁ and R ₀₂ are each an alkyl group, an aryl group, an alkoxy group, an aryloxy group, or an amino group.

[0112 formula (III), may be different even in the same and R ₀₁ and R _02, when a R _{0 1} and R ₀₂ there are a plurality each, R ₀₁ comrades, R ₀₂ comrades are each identical However, they may be different.

In the formula (III), L ₁ represents a single bond or an arylene group. The arylene group represented by L ₁ is preferably unsubstituted. Specifically, in addition to a normal arylene group such as a phenylene group, a biphenylene group, and an anthrylene group, two or more arylene groups may be directly substituted. And linked ones. L ₁ is preferably a single bond, a p-phenylene group, a 4,4′-biphenylene group or the like.

The arylene group represented by L ₁ is 2
One or more arylene groups are alkylene groups, -O
-, -S- or -NR- may be interposed and linked. Here, R represents an alkyl group or an aryl group. Examples of the alkyl group include a methyl group and an ethyl group, and examples of the aryl group include a phenyl group. Among them, the aryl group is preferred, other phenyl group of the above, A _1, may be A _2, further it may be those A ₁ or A ₂ is substituted in the phenyl group.

Further, as the alkylene group, a methylene group,
Ethylene groups and the like are preferred. Specific examples of such an arylene group are shown below.

[0116]

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Next, the formula (IV) will be described. The formula (I
In V), R ₀₃ and R ₀₄ correspond to R ₀₁ in formula _{( II)}
And R ₀₂ , r03 and r04 represent r01 and r02 in the formula (III), and L ₂ represents a compound represented by the formula (III)
Has the same meaning as L _1, and preferred ones are also the same.

[0118 formula (IV), may be one that is different even in the same and R ₀₃ and R _04, when R ₀₃ and R ₀₄ there are a plurality each, R ₀₃ comrades, R ₀₄ comrades in each identical It may be different.

The compounds represented by the formulas (III) and (IV) are exemplified below, but are not limited thereto.
In addition, Chemical Formula 21, Chemical Formula 23, Chemical Formula 25, Chemical Formula 27, Chemical Formula 29, Chemical Formula 3
1, Formula 33 shows a general formula, and Chemical Formulas 22, 24, and 2
6, Chemical Formula 28, Chemical Formula 30, Chemical Formula 32, Chemical Formula 34, R _{11 to} R ₁₅ , R _{21 to} R ₂₅ or R _{31 to} R ₃₅ ,
This is indicated by a combination of R _{41 to} R ₄₅ .

[0120]

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[0121]

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[0122]

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[0123]

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[0124]

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[0125]

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[0126]

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[0127]

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[0128]

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[0129]

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[0130]

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[0131]

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[0132]

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[0133]

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[0134]

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[0135]

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[0136]

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[0137]

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Further, the tetraarylethene derivative is a compound represented by the following general formula (V).

[0139]

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In the general formula (V), Ar ₅₁ , Ar ₅₂ and Ar ₅₃ each represent an aromatic residue, which may be the same or different.

Examples of the aromatic residue represented by Ar _{51 to} Ar ₅₃ include an aromatic hydrocarbon group (aryl group) and an aromatic heterocyclic group. The aromatic hydrocarbon group may be a monocyclic or polycyclic aromatic hydrocarbon group, and includes a condensed ring and a ring assembly. The aromatic hydrocarbon group has a total carbon number of 6 to
Those having 30 are preferred, and those having a substituent may be used. When it has a substituent, examples of the substituent include an alkyl group, an aryl group, an alkoxy group, an aryloxy group, and an amino group. This substituent will be described later.
As the aromatic hydrocarbon group, for example, phenyl group, alkylphenyl group, alkoxyphenyl group, arylphenyl group, aryloxyphenyl group, aminophenyl group, biphenyl group, naphthyl group, anthryl group, pyrenyl group,
And a perylenyl group.

The aromatic heterocyclic group preferably contains O, N and S as a hetero atom, and may be a 5-membered ring or a 6-membered ring. Specific examples include a thienyl group, a furyl group, a pyrrolyl group, and a pyridyl group.

As the aromatic group represented by Ar _{51 to} Ar ₅₃ , a phenyl group is particularly preferred.

N51 is an integer of 2 to 6, especially 2 to 4
Is preferably an integer.

L ₅₁ represents an n-valent aromatic residue, and is preferably a divalent to hexavalent, particularly divalent to tetravalent, derivative derived from an aromatic hydrocarbon, an aromatic heterocycle, an aromatic ether or an aromatic amine. It is preferably a residue. These aromatic residues may further have a substituent, but are preferably unsubstituted.

Of the tetraarylethene derivatives represented by the formula (V), those represented by the following formula (VI) are preferable.

[0147]

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In the formula (VI), R ₆₁ , R ₆₂ and R ₆₃
Represents an alkyl group, an aryl group, an alkoxy group, an aryloxy group or an amino group, which may be the same or different.

The alkyl group represented by R _{61 to} R ₆₃ is preferably an alkyl group having 1 to 10 carbon atoms, which may be linear or branched, and further having a substituent. May be included, for example, a methyl group, an ethyl group, an n-propyl group, an i-propyl group, an n-butyl group,
and a t-butyl group.

The aryl group represented by R _{61 to} R ₆₃ preferably has 6 to 20 carbon atoms and may have a substituent, for example, a phenyl group, an o-tolyl group, and an m-tolyl group. Group, p-tolyl group, naphthyl group, anthryl group and the like.

The alkoxy group represented by R _{61 to} R ₆₃ is preferably an alkoxy group having 1 to 6 carbon atoms in the alkyl group of the alkoxy group. For example, methoxy, ethoxy, t-
Butoxy group and the like.

The aryloxy groups represented by R _{61 to} R ₆₃ include a phenoxy group, a 4-methylphenoxy group,
(T-butyl) phenoxy group and the like.

The amino groups represented by R _{61 to} R ₆₃ include:
Those having a substituent are preferable, and examples thereof include a dimethylamino group, a diethylamino group, a diphenylamino group, and a bis (biphenyl) amino group.

S, t and u are each 0 or 1 to 5
When s, t, and u are integers of 2 or more,
R ₆₁ , R ₆₂ , and R ₆₃ may be the same or different.

In the formula (VI), s, t and u are each preferably 0 or 1, particularly preferably 0, that is, an unsubstituted phenyl group.

[0156] L ₆₁ represents an arylene group, Arentoriiru group, a heterocyclic diyl group, triarylamine tri-yl group or diaryl heterocyclic tetrayl group. Arylene group represented by L ₆₁ is preferably an oxy group (-O-), a thio group (-
S-), a heterocyclic diyl group or an alkylene group may be interposed.

Such an arylene group has a total carbon number of 6
-20, and specific examples include a phenylene group, a biphenylene group, a naphthylene group, a diphenyletherdiyl group, a diphenylthioetherdiyl group, a diphenylmethyldiyl group, a diphenyloxadiazolediyl group, and a terphenylene group.

[0158] As Arentoriiru group represented by L ₆₁ is benzenetriyl group, quaterphenyl tri-yl group and the like.

[0159] As heterocyclic diyl group represented by L ₆₁ are,
Thiophendiyl group, furandiyl group, pyridinediyl group, bithiophendiyl group, bifurandiyl group, bipyridinediyl group, pyrazinediyl group, pyrrolediyl group,
Examples include a bipyrrolediyl group, a quinolinediyl group, an oxadiazolediyl group, a quinoxalinediyl group, and a diphenylquinoxalinediyl group.

[0160] As triarylamine tri-yl group represented by L _61, the triphenylamine tri-yl group and the like.

[0161] As the diaryl heterocyclic tetrayl group represented by L ₆₁ include diphenyl quinoxaline tetrayl group.

[0162] Although the following preferred examples of L _61, but is not limited thereto.

[0163]

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[0164]

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[0165] formula (VI), n61 is dependent on the valence of L _61, an integer of 2 to 4, further 2,3, especially 2
It is preferred that

Preferred examples of the tetraarylethene derivative are shown below, but it should not be construed that the invention is limited thereto. In addition,
Chemical formula 43 is a general formula, and chemical formulas 44, 45, and 46 are shown using the chemical formula 43. R _{71 to} R ₇₅ , R _{81 to} R
_{As for 85} and R _{91 to} R ₉₅ , when all are hydrogen, it is H, and when any one is a substituent, only a substituent is shown.

[0167]

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[0168]

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[0169]

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[0170]

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[0171]

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[0172]

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<Other Fluorescent Substance> In the present invention, the light emitting layer may contain another fluorescent substance in addition to the compound of the formula (I). Examples of such a fluorescent substance include compounds disclosed in JP-A-63-264892, for example, at least one selected from compounds such as quinacridone, rubrene, and styryl dyes.
In addition, tris (8-quinolinolato) aluminum or the like
And quinoline derivatives such as metal complex dyes having -quinolinol or a derivative thereof as a ligand, tetraphenylbutadiene, anthracene, perylene, coronene, and 12-phthaloperinone derivatives. Further, Japanese Unexamined Patent Publication No.
Phenylanthracene derivative of JP-A-012600 and tetraarylethene derivative of JP-A-8-012969.

<Mixed layer> The light-emitting layer containing the compound of the formula (I) may be combined with the above-mentioned host substance, or may be combined with at least one kind of hole injecting / transporting compound and at least one kind of electron. It is also preferable to form a mixed layer with an injection-transporting compound, and it is preferable that the compound of the general formula (I) is contained in the mixed layer as a dopant. The content of the compound of the general formula (I) in such a mixed layer is 0.01 to 20% by weight, more preferably 0.1 to 20% by weight.
It is preferably 15 wt%.

In the mixed layer, a carrier hopping conduction path is formed, so that each carrier moves in a material having a favorable polarity, and carrier injection of the opposite polarity is unlikely to occur, so that the organic compound is less likely to be damaged. This has the advantage that the element life is extended. By including the compound of the general formula (I) in such a mixed layer, the emission wavelength characteristics of the mixed layer itself can be changed, the emission wavelength can be shifted to a longer wavelength, and the emission intensity can be reduced. And the stability of the element is improved.

The hole injecting and transporting compound and the electron injecting and transporting compound used in the mixed layer may be selected from the following compounds for the hole injecting and transporting layer and the compounds for the electron injecting and transporting layer, respectively. Among them, as the electron injecting and transporting compound, it is preferable to use a quinoline derivative, furthermore, a metal complex having 8-quinolinol or a derivative thereof as a ligand, particularly tris (8-quinolinolato) aluminum (AlQ3). It is also preferable to use a phenylanthracene derivative or a tetraarylamine derivative. Examples of the compound for the hole injecting and transporting layer include amine derivatives having strong fluorescence, for example, a tetraaryl arylenediamine derivative which is a hole transporting material, a styrylamine derivative, an amine derivative having an aromatic condensed ring, and a triarylamine. It is preferred to use derivatives.

The above tetraaryl arylenediamine derivative is represented by the following general formula (101).

[0178]

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In the formula (101), Are represents an arylene group, n100 is an integer of 1 to 4, and A ₁₀₁ to
A ₁₀₄ represents an aryl group. A _{101 to} A ₁₀₄ may be the same or different.

The arylene group represented by Are may further have a substituent such as an alkyl group, an alkoxy group, an aryl group, an aryloxy group and a halogen atom. Preferred examples of the arylene group represented by Are include a phenylene group, a biphenylene group, a terphenylene group, a thienylene group, and a bithienylene group.

The aryl group represented by A _{101 to} A ₁₀₄ is
Further, it may have a substituent such as an alkyl group, an alkoxy group, an aryl group, an aryloxy group and a halogen atom. A _{101 to} A ₁₀₄ are preferably phenyl, biphenyl, diarylaminophenyl, diarylaminobiphenyl, methoxyphenyl, phenoxyphenyl and the like.

Specific examples of the tetraaryl arylenediamine derivative include JP-A-63-295695, JP-A-2-191694, JP-A-3-792, and JP-A-5-792.
JP-A-234681, JP-A-5-239455, JP-A-5-299174, JP-A-7-126225, JP-A-7-126226, JP-A-8-100172, E
P0650955A1 (Corresponding Japanese Patent Application No. Hei 7-43564)
And the like.

Among them, compounds represented by the following formulas (102) to (105) are preferred as the tetraarylarylenediamine derivative.

[0184]

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In the formula (102), R ₁₀₇ , R ₁₀₈ ,
R ₁₀₉ and R ₁₁₀ each represent an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an amino group, or a halogen atom, which may be the same or different. r107, r108, r109 and r110 are each an integer of 0 to 4. R ₁₁₁ ,
R ₁₁₂ , R ₁₁₃ and R ₁₁₄ each represent an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an amino group or a halogen atom, which may be the same or different. r111, r112, r1
13 and r114 are each an integer of 0 to 5. R
₁₀₅ and R ₁₀₆ each represent an alkyl group, an alkoxy group, an amino group or a halogen atom, which may be the same or different. r105 and r106 are each an integer of 0 to 4.

[0186]

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In the formula (103), R ₁₀₇ , R ₁₀₈ ,
R ₁₀₉ and R ₁₁₀ each represent an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an amino group, or a halogen atom, which may be the same or different. r107, r108, r109 and r110 are each an integer of 0 to 4. R ₁₁₁ ,
R ₁₁₂ , R ₁₁₃ and R ₁₁₄ each represent an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an amino group or a halogen atom, which may be the same or different. r111, r112, r1
13 and r114 are each an integer of 0 to 5. R
₁₀₅ and R ₁₀₆ each represent an alkyl group, an alkoxy group, an amino group or a halogen atom, which may be the same or different. r105 and r106 are each an integer of 0 to 4.

[0188]

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In the formula (104), R ₁₀₇ , R ₁₀₈ ,
R ₁₀₉ and R ₁₁₀ each represent an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an amino group, or a halogen atom, which may be the same or different. r107, r108, r109 and r110 are each an integer of 0 to 4. R ₁₁₁ ,
R ₁₁₂ , R ₁₁₃ and R ₁₁₄ each represent an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an amino group or a halogen atom, which may be the same or different. r111, r112, r1
13 and r114 are each an integer of 0 to 5. R
₁₀₅ and R ₁₀₆ each represent an alkyl group, an alkoxy group, an amino group or a halogen atom, which may be the same or different. r105 and r106 are each an integer of 0 to 4.

[0190]

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In the formula (105), Ar ₁₀₄ and A
r ₁₀₅ represents a diarylaminoaryl group,
These may be the same or different. R ₁₁₅ and R ₁₁₆ each represent an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an amino group or a halogen atom, which may be the same or different. r115 and r116 are each 0 to 4
Is an integer. R ₁₁₇ and R ₁₁₈ each represent any of an alkyl group, an alkoxy group, an aryloxy group, an amino group, and a halogen atom, which may be the same or different. r117 and r118 are each an integer of 0 to 5. R ₁₀₅ and R ₁₀₆ each represent an alkyl group, an alkoxy group, an amino group, or a halogen atom, which may be the same or different. r105 and r106 are each 0
-4.

The formulas (102) to (104) will be further described. In each of the formulas (102) to (104), R _{111 to} R ₁₁₄ represent an aryl group, an alkyl group, an alkoxy group, and an aryloxy group, respectively. , An amino group or a halogen atom, which may be the same or different.

The aryl group represented by R _{111 to} R ₁₁₄ may be monocyclic or polycyclic, and includes condensed rings and ring assemblies. The total carbon number is preferably 6 to 20, and may have a substituent. Examples of the substituent in this case include an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an amino group, and a halogen atom.

Specific examples of the aryl group represented by R _{111 to} R ₁₁₄ include a phenyl group, an (o-, m-, p-) tolyl group, a pyrenyl group, a perylenyl group, a coronenyl group, a naphthyl group and an anthryl group , A biphenylyl group, a phenylanthryl group, a tolylanthryl group and the like, and a phenyl group is particularly preferred. The bonding position of the aryl group, particularly the phenyl group, is preferably at the 3-position (meta-position relative to the N-bonding position) or the 4-position (para position relative to the N-bonding position).

The alkyl group represented by R _{111 to} R ₁₁₄ may be linear or branched, preferably has 1 to 10 carbon atoms, and may have a substituent. Good. In this case, examples of the substituent include those similar to the aryl group.

Examples of the alkyl group represented by R _{111 to} R ₁₁₄ include a methyl group, an ethyl group, an (n-, i-) propyl group,
(N-, i-, s-, t-) butyl group and the like.

The alkoxy group represented by R _{111 to} R ₁₁₄ preferably has 1 to 6 carbon atoms in the alkyl portion.
Specific examples include a methoxy group, an ethoxy group, and a t-butoxy group. The alkoxy group may be further substituted.

The aryloxy groups represented by R _{111 to} R ₁₁₄ include a phenoxy group, a 4-methylphenoxy group,
— (T-butyl) phenoxy group and the like.

The amino group represented by R _{111 to} R ₁₁₄ may be unsubstituted or may have a substituent.
Those having a substituent are preferable, and specifically, a dimethylamino group, a diethylamino group, a diphenylamino group, a ditolylamino group, a dibiphenylylamino group, an N-phenyl-N-tolylamino group, an N-phenyl-N-naphthylamino group , N-phenyl-N-biphenylylamino group, N
-Phenyl-N-anthrylamino group, N-phenyl-
Examples thereof include an N-pyrenylamino group, a dinaphthylamino group, a dianthrylamino group, and a dipyrenylamino group.

Examples of the halogen atom represented by R _{111 to} R ₁₁₄ include a chlorine atom and a bromine atom.

Each of r111 to r114 is an integer of 0 to 5, and is preferably 0 in any of formulas (102) to (104).

[0202] Note that when r111~r114 are each an integer of 2 or more, each R ₁₁₁ to R ₁₁₄ each other may be the same or different.

In the formulas (102) to (104), R
_105, the alkyl group represented by R _106, an alkoxy group, an amino group, a halogen atom include the same groups at the R ₁₁₁ to R _114.

Both r105 and r106 are preferably 0, and the biphenylene group linking two arylamino groups is preferably unsubstituted.

In the formulas (102) to (104), R
₁₀₇ to R ₁₁₀ are each an alkyl group, an alkoxy group, an aryl group, an aryloxy group, or an amino group or a halogen atom, it may be be the same or different. Specific examples thereof include the same ones as those described for R _{111 to} R ₁₁₄ .

Each of r107 to r110 is an integer of 0 to 4, and is preferably 0.

The equation (105) will be further described.
In the formula (105), Ar ₁₀₄ and Ar ₁₀₅ each represent a diarylaminoaryl group, which may be the same or different. As the diarylaminoaryl group, a diarylaminophenyl group is preferable, and specifically, a diphenylaminophenyl group, a bis (biphenyl) aminophenyl group, a biphenylphenylaminophenyl group, a ditolylaminophenyl group, a phenyltolylaminophenyl group, and a naphthyl Examples include a phenylaminophenyl group, a dinaphthylaminophenyl group, and a phenylpyrenylaminophenyl group.

In the formula (105), R ₁₁₅ and R ₁₁₆
Represents an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an amino group, or a halogen atom, which may be the same or different. Formulas (102) to (104) are specific examples of these.
And the same ones as those described for R _{111 to} R ₁₁₄ can be used.

[0209] r115 and r116 are each an integer of 0 to 4, preferably 0.

In the formula (105), R ₁₁₇ and R ₁₁₈ are
An alkyl group, an alkoxy group, an aryloxy group,
Represents either an amino group or a halogen atom, which may be the same or different. Specific examples thereof include the same ones as those described for R _{111 to} R ₁₁₄ .

Each of r117 and r118 is an integer of 0 to 5, preferably 0.

In the equation (105), r115,
When r116 are each an integer of 2 or more, R ₁₁₅ to each other,
R ₁₁₆ may be the same or different, and when r ₁₁₇ and r ₁₁₈ are each an integer of 2 or more, R ₁₁₇ and R ₁₁₈ may be the same or different.

In the formula (105), R ₁₀₅ , R ₁₀₆ ,
r105 and r106 have the same meanings as those in formulas (102) to (104), and r105 and r106 are preferably 0.

Hereinafter, specific examples of the tetraarylarylenediamine derivative will be shown, but the invention is not limited thereto. Specific examples include the general formulas (102a) to (1)
Indicated 05a), shows a combination of R ^101, etc. In these formulas. In this notation, except for Ar _{101 to} Ar ₁₀₆ , all Hs are indicated by H, and when a substituent is present, only the substituent is indicated; ing.

[0215]

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[0216]

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[0219]

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[0218]

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[0219]

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[0220]

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[0221]

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[0222]

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[0223]

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[0224]

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[0225]

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[0226]

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[0227]

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[0228]

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[0229]

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[0230]

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[0231]

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[0232]

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[0233]

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[0234]

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[0235]

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The following compounds are also preferred.

[0237]

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Further, a triarylamine polymer having a phenylenediamine skeleton used as a hole injection material described later is also preferable.

In the case where the light emitting layer is a mixed layer of at least one or more hole injecting and transporting compounds and at least one or more electron injecting and transporting compounds, the mixing ratio depends on the respective carrier mobilities and carrier concentrations. In general, the weight ratio of the compound having a hole injecting and transporting compound / the compound having an electron injecting and transporting function is 1/99 to 99/1, and more preferably 10/99.
It is preferable that the ratio be about 90 to 90/10, particularly about 20/80 to 80/20.

Further, the thickness of the mixed layer is preferably less than the thickness of the organic compound layer from the thickness corresponding to one molecular layer, more preferably 1 to 85 nm.
Further, the thickness is preferably 5 to 60 nm, particularly preferably 5 to 50 nm.

As a method of forming a mixed layer, co-evaporation in which evaporation is performed from different evaporation sources is preferable. However, when the vapor pressures (evaporation temperatures) are approximately the same or very close, they are mixed in advance in the same evaporation board. Alternatively, it can be deposited. In the mixed layer, it is preferable that the compounds are uniformly mixed, but in some cases, the compounds may exist in an island shape. The light-emitting layer is generally formed to a predetermined thickness by vapor-depositing an organic fluorescent substance or by dispersing and coating the resin in a resin binder.

<Electron Injection / Transport Layer> In the invention, an electron injection / transport layer may be provided. The electron injecting and transporting layer has a thickness of 8 such as tris (8-quinolinolato) aluminum (AlQ3).
Quinolinol derivatives such as organometallic complexes having quinolinol or a derivative thereof as a ligand, oxadiazole derivatives, perylene derivatives, pyridine derivatives, pyrimidine derivatives, quinoxaline derivatives, diphenylquinone derivatives, nitro-substituted fluorene derivatives and the like can be used. . The electron injecting and transporting layer may also serve as the light emitting layer. In such a case, it is preferable to use tris (8-quinolinolato) aluminum (AlQ3) or the like. The electron injecting and transporting layer may be formed by vapor deposition or the like, similarly to the light emitting layer.

When the electron injecting and transporting layer is provided separately for the electron injecting layer and the electron transporting layer, a preferable combination can be selected from the compounds for the electron injecting and transporting layer. At this time, it is preferable to laminate the compounds having the higher electron affinity from the cathode side, and it is preferable to provide an electron injection layer in contact with the cathode and an electron transport layer in contact with the light emitting layer. The relationship between the electron affinity and the stacking order is the same when two or more electron injection / transport layers are provided.

<Hole Injection / Transport Layer> In the invention, a hole injection / transport layer may be provided. In the hole injection transport layer, various organic compounds used in ordinary organic EL devices, for example,
JP-A-63-29569, JP-A-2-1916
94, JP-A-3-792 and the like, specifically, tetraaryl arylenediamine derivatives, triarylamine derivatives, hydrazone derivatives, carbazole derivatives, triazole derivatives, imidazole derivatives, amino acids An oxadiazole derivative having a group, oligothiophene, polythiophene, or the like can be used. In particular, it is preferable to use a tetraaryl arylenediamine derivative or a triarylamine derivative. These compounds may be used as a mixture of two or more kinds, or may be used by laminating.

When the hole injecting and transporting layer is provided separately as a hole injecting layer and a hole transporting layer, a preferred combination can be selected from the compounds for the hole injecting and transporting layer. At this time, it is preferable to stack the compounds in order from the anode (ITO or the like) side with the smaller ionization potential.
It is preferable to provide a hole injection layer in contact with the anode and a hole transport layer in contact with the light emitting layer. Further, it is preferable to use a hole-injecting material having a good thin film property, which can form a uniform thin film even on an ITO surface having a variation in hydrophilicity, and a triarylamine having a phenylenediamine skeleton. Multimers are preferred. The relationship between the ionization potential and the stacking order is the same when two or more hole injection / transport layers are provided. With such a stacking order, the driving voltage is reduced, and the occurrence of current leakage and the occurrence and growth of dark spots can be prevented. In addition, when the device is formed, since evaporation is used, it is 1 to
Even a thin film of about 10 nm can be made uniform and pinhole-free. Therefore, even if a compound having a small ionization potential in the hole injection layer and having absorption in the visible region is used, the change in color tone of the emission color and the A decrease in efficiency due to absorption can be prevented. Further, by adjusting the film thickness, the refractive index, and the like, it is possible to prevent a decrease in efficiency by utilizing an interference light effect such as a light emission color, light emission luminance, and light emission spatial distribution.

When two or more hole injection / transport layers are laminated,
Alternatively, when a hole injecting layer and a hole transporting layer are laminated, a triarylamine polymer having a phenylenediamine skeleton having a good thin film property is used on the anode for the hole injecting layer or the first hole injecting and transporting layer. Preferably, a tetraaryl arylenediamine derivative is used for the hole transport layer or the second hole injection / transport layer.

In addition to the above, preferred aromatic tertiary amines include those described in Japanese Patent Application No. 7-43564. Specifically, N, N, N ', N'-tetra (3-
Biphenylyl) benzidine, N, N'-diphenyl-
N, N'-bis [4 '-(N-phenyl-N-3-methylphenylamino) biphenyl-4-yl] benzidine, N, N'-diphenyl-N, N'-bis [4'-
(N, N-di-3-biphenylylamino) biphenyl-
4-yl] benzidine, N, N'-diphenyl-N,
N'-bis [4 '-(N-phenyl-N-2-naphthylamino) biphenyl-4-yl] benzidine, N, N'
-Diphenyl-N, N'-bis [4 '-(N-phenyl-N-3-biphenylylamino) biphenyl-4-yl] benzidine, N, N'-diphenyl-N, N'-bis [4' -(N, N'-di-3-methylphenylamino) biphenyl-4-yl] benzidine and the like.

<Cathode> In the present invention, a material having a small work function, for example, Li, Na, Mg, Al,
It is preferable to use Ag, In, or an alloy containing one or more of these. The cathode preferably has fine crystal grains, and particularly preferably has an amorphous state. The thickness of the cathode is preferably about 10 to 1000 nm.

In the electron injection layer, Li, Na, K, C
A metal having a small work function such as a may be dispersed.

Also, oxides and halides of Li, Na, K, Mg, and Ca are formed into thin films of 1 nm or less, and
An electrode such as 1 may be formed.

<Anode> At least one electrode needs to be transparent or translucent in order for the organic EL element to emit light from the surface, and the material of the cathode is limited as described above. It is preferable to determine the material and thickness of the anode such that the transmittance of the anode is 80% or more. Specifically, for example, ITO (tin-doped indium oxide), IZO (zinc-doped indium oxide), Sn
It is preferable to use O ₂ , Ni, Au, Pt, Pd, polypyrrole doped with a dopant, or the like for the anode. Further, the thickness of the anode is preferably about 10 to 500 nm. Further, in order to improve the reliability of the element, it is necessary that the driving voltage is low.
30Ω / □ or 10Ω / □ or less (usually 0.1 to 10Ω)
/ □).

A compound that generates hole carriers may be dispersed in the hole injection layer.

<Substrate Material> Although there is no particular limitation on the substrate material, in the illustrated example, a transparent or translucent material such as glass or resin is used in order to extract emitted light from the substrate side. Further, the emission color may be controlled by using a color filter film, a color conversion film containing a fluorescent substance, or a dielectric reflection film on the substrate, or coloring the substrate itself. When an opaque material is used for the substrate, the stacking order shown in FIG. 5 may be reversed.

<Method of Manufacturing Organic EL Element> Next, a method of manufacturing the organic EL element of the present invention will be described. The anode is preferably formed by a vapor phase growth method such as an evaporation method or a sputtering method.

The cathode may be formed by a vapor deposition method, but is preferably formed by a sputtering method. The sputtering method
Even when a mixture of materials having greatly different vapor pressures is used as the target, there is little deviation in the composition between the film to be formed and the target, and there is no limitation on the material used due to the vapor pressure or the like as in the vapor deposition method. Further, as compared with the vapor deposition method, it is not necessary to supply a material for a long time, the film thickness and the film quality are excellent, and the productivity is advantageous.

For forming the hole injecting and transporting layer, the light emitting layer and the electron injecting and transporting layer, it is preferable to use a vacuum evaporation method since a uniform thin film can be formed. When a vacuum deposition method is used, a homogeneous thin film having an amorphous state or a crystal grain size of 0.1 μm or less (the lower limit is usually about 0.001 μm) can be obtained. If the crystal grain size exceeds 0.1 μm, the light emission becomes non-uniform, the driving voltage of the device must be increased, and the charge injection efficiency is significantly reduced.

The conditions for vacuum deposition are not particularly limited.
0 ^-3 Pa or less, preferably a degree of vacuum of 10 ^-5 Pa, the deposition rate is preferably about 0.01 to 1 / sec. Further, it is preferable to form each layer continuously in a vacuum. If they are formed continuously in a vacuum, impurities can be prevented from adsorbing at the interface between the layers, so that high characteristics can be obtained. Further, the driving voltage of the element can be reduced, and the growth and generation of dark spots can be suppressed.

In the case where a plurality of compounds are contained in one layer when the vacuum evaporation method is used for forming each of these layers, it is preferable to co-deposit each boat containing the compounds by controlling the temperature of each boat individually. After that, vapor deposition may be performed.
In addition, the solution coating method (spin coating, dip,
Cast, etc.), the Langmuir-Blodgett (LB) method and the like can also be used. In the solution coating method, each compound may be dispersed in a matrix material such as a polymer.

The organic EL device of the present invention is usually used as a DC-driven EL device, but can be driven by AC or pulse. The applied voltage is usually 2 to 20
V.

[0260]

EXAMPLES Hereinafter, the present invention will be described in more detail by showing specific examples of the present invention. Example 1 A glass substrate on which a 200-nm-thick ITO transparent electrode (anode) was formed was subjected to ultrasonic cleaning using a neutral detergent, acetone, and ethanol. The substrate is taken out of boiling ethanol, dried, washed with UV / O ₃ , fixed to a substrate holder of a vacuum evaporation apparatus, and the
^The pressure was reduced to ^-4 Pa or less.

First, the following HIM34 was deposited at a vapor deposition rate of about 0.1.
It was deposited at a thickness of about 50 nm at 1 nm / sec to form a hole injection layer. Next, TPD (No. 102-1 of Chemical Formula 55) was deposited at a deposition rate of 0.2 nm / sec to a thickness of 20 nm to form a hole transport layer.

[0262]

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While maintaining the reduced pressure, tris (8-quinolinolato) aluminum (hereinafter referred to as AlQ3) and No. 2 of Chemical formula 5 were each deposited at a deposition rate of 0.1 to 0.2 nm /.
A co-evaporation was performed at a rate of 0.002 to 0.004 nm / sec (2.0 wt%) for a total thickness of about 20 nm to form a light emitting layer.

Next, AlQ3 is deposited at a deposition rate of 0.1 to 0.1.
It was deposited at a thickness of about 30 nm at 2 nm / sec to form an electron injecting and transporting layer.

Next, while maintaining the reduced pressure, an AlLi alloy film (Li concentration 0.7 at%) was formed to a thickness of 200 nm to form a cathode.

When a voltage was applied to this organic EL element to cause a current to flow, a drive voltage of 7.8 V, a constant current density of 10 mA / cm ² and a green color of 1200 cd / m ² (maximum emission wavelength λmax =
528 nm).

The device was placed in a dry atmosphere at 50 mA / cm ²
, The initial luminance was 5400 cd / m ² , the initial driving voltage was 8.5 V, the half-life of the luminance was 680 hours or more, and the driving voltage increased during that time was 2.0 V.

When the light emitting layer is composed of only AlQ3, the emission color is green, the peak wavelength is 520 nm, and the emission color is green.
The luminance at a constant current density of mA / cm ² was 300 cd / m ² .

[Example 2] AlQ3 and No. 53 of Chemical formula 11
Was obtained in the same manner as in Example 1 except that a light-emitting layer was obtained by co-evaporation.

When a voltage was applied to the organic EL device to cause a current to flow, a driving voltage of 8.0 V, a constant current density of 10 mA / cm ² and a green color of 1150 cd / m ² (maximum emission wavelength λmax =
530 nm).

The device was placed in a dry atmosphere at 50 mA / cm ²
, The initial luminance was 5200 cd / m ² , the initial driving voltage was 8.8 V, the half-life of the luminance was 650 hours or more, and the driving voltage increased during that time was 1.5 V.

[Example 3] EQ was prepared in the same manner as in Example 1 except that AlQ3 and No. 1 of Chemical formula 5 were co-evaporated to form a light emitting layer.
An L element was obtained.

When a voltage was applied to this organic EL device to cause a current to flow, a drive voltage of 8.1 V, a constant current density of 10 mA / cm ² and a yellow-green color of 1100 cd / m ² (the maximum emission wavelength λmax
= 535 nm).

The device was dried at 50 mA / cm ^{2 in a} dry atmosphere.
, The initial luminance was 4900 cd / m ² , the initial driving voltage was 8.8 V, the half-life of the luminance was 700 hours or more, and the driving voltage rise during that time was 2.0 V.

Example 4 A glass substrate on which a 200-nm-thick ITO transparent electrode (anode) was formed was subjected to ultrasonic cleaning using a neutral detergent, acetone, and ethanol. The substrate was pulled out of boiling ethanol, dried, washed with UV / O ₃ , fixed to a substrate holder of a vacuum evaporation apparatus, and the pressure in the vacuum chamber was reduced to 1 × 10 ⁻⁴ Pa or less.

First, the HIM 34 was deposited at a deposition rate of about 0.1 nm / s.
Evaporation was performed to a thickness of about 10 nm by ec to form a hole injection layer. Next, TPD (No. 102-1 of Chemical Formula 55) was vapor-deposited at a deposition rate of 0.1%.
It was deposited at a thickness of about 45 nm at a rate of 1 to 0.2 nm / sec to form a hole transport layer.

While maintaining the reduced pressure, TPD as a hole injecting and transporting compound (No. 102-
1) and AlQ3 as an electron injecting / transporting compound at almost the same deposition rate (0.1 to 0.2 nm / sec), and at the same time, No. 2 of Chemical formula 5 also has a deposition rate of 0.006 to 0.014 nm / se.
A mixed layer as a light emitting layer was formed to a thickness of about 40 nm by vapor deposition with c (3.3 wt%).

Then, AlQ3 is deposited at a deposition rate of 0.1 to 0.1.
It was deposited at a thickness of about 30 nm at 2 nm / sec to form an electron injecting and transporting layer.

Next, while maintaining the reduced pressure, an AlLi alloy film (Li concentration 0.7 at%) was formed to a thickness of 200 nm to form a cathode.

When a voltage was applied to this organic EL device to cause a current to flow, a drive voltage of 8.2 V, a constant current density of 10 mA / cm ² and a green color of 1280 cd / m ² (maximum emission wavelength λmax =
528 nm).

The device was placed in a dry atmosphere at 50 mA / cm ²
, The initial luminance was 5800 cd / m ² , the initial driving voltage was 8.7 V, the half-life of the luminance was 2,000 hours or more, and the driving voltage increased during that time was 1.6 V.

Example 5 TPD (No. 105 of Chemical Formula 72)
EL-3 in the same manner as in Example 4, except that AlQ3 and No. 2 of Chemical formula 5 were co-evaporated to form a mixed layer as a light emitting layer.
An element was obtained.

When a voltage was applied to this organic EL device to cause a current to flow, a driving voltage of 7.5 V, a constant current density of 10 mA / cm ² and a green color of 1020 cd / m ² (the maximum emission wavelength λmax =
529 nm).

The device was placed in a dry atmosphere at 50 mA / cm ²
, The initial luminance was 4500 cd / m ² , the initial driving voltage was 7.9 V, the half-life of the luminance was 4000 hours or more, and the increase in the driving voltage during that time was 1.0 V.

Example 6 TPD (No. 105 of Chemical Formula 72)
EL-3 in the same manner as in Example 4, except that AlQ3 and No. 1 of Chemical formula 5 were co-evaporated to form a mixed layer as a light emitting layer.
An element was obtained.

When a voltage was applied to this organic EL element to cause a current to flow, a driving voltage of 7.8 V, a constant current density of 10 mA / cm ² and a green color of 1050 cd / m ² (maximum emission wavelength λmax =
535 nm).

The device was placed in a dry atmosphere at 50 mA / cm ²
, The initial luminance was 4300 cd / m ² , the initial driving voltage was 7.8 V, the half-life of the luminance was 3000 hours or more, and the driving voltage rose 1.8 V during that time.

Comparative Example 1 An EL device was obtained in the same manner as in Example 1, except that AlQ3 and 5,12-diphenylnaphthacene were co-evaporated to form a light emitting layer.

When a voltage was applied to the organic EL device to cause a current to flow, a drive voltage of 8.2 V, a constant current density of 10 mA / cm ² and a green color of 450 cd / m ² (maximum emission wavelength λmax = 5)
19 nm) was confirmed.

The device was placed in a dry atmosphere at 50 mA / cm ²
, The initial luminance was 1800 cd / m ² , the initial driving voltage was 8.9 V, the half-life of the luminance was 120 hours or more, and the driving voltage increased during that time was 3.0 V.

[Comparative Example 2] TPD (No. 102 of Chemical Formula 55)
-1), AlQ3 and 5,12-diphenylnaphthacene were co-evaporated to obtain an EL element in the same manner as in Example 4, except that the mixed layer was used as a light emitting layer.

When a voltage was applied to this organic EL device to cause a current to flow, a driving voltage of 8.1 V, a constant current density of 10 mA / cm ² and a green color of 430 cd / m ² (maximum emission wavelength λmax = 5)
18 nm) was confirmed.

The device was placed in a dry atmosphere at 50 mA / cm ²
, The initial luminance was 1900 cd / m ² , the initial driving voltage was 8.7 V, the half-life of the luminance was 900 hours or more, and the driving voltage increased during that time was 3.0 V.

The organic EL device of the present invention has high luminance, can emit light of a long wavelength, has a long half-life, and has excellent durability.

[0295]

According to the present invention, luminescence of sufficient luminance is obtained because the fluorescence intensity is high, the resistance to electrons and holes is high, the carrier trapping property is high, and the recombination probability of electrons and holes is high. In particular, it is possible to obtain an organic EL device which emits light of a long wavelength and has excellent durability, which maintains good light emitting performance for a long time.

[Brief description of the drawings]

FIG. 1 is a Mass (mass spectrometry) spectrum of 5,12-bis [-4- (2-phenylethenyl) phenyl] naphthacene.

FIG. 2. 5,12-Bis [-4- (2-phenyletheni
Yl) phenyl] naphthacene ¹H-NMR spectrum
is there.

FIG. 3. 5,12-Bis [-4- (2-phenyletheni
Yl) phenyl] naphthacene ¹³C-NMR spectrum
It is.

FIG. 4 is an IR spectrum of 5,12-bis [-4- (2-phenylethenyl) phenyl] naphthacene.

FIG. 5 is a schematic sectional view showing a configuration example of an organic EL device of the present invention.

[Explanation of symbols]

 Reference Signs List 1 substrate 2 anode 3 hole injection / transport layer 4 light emitting layer 5 electron injection / transport layer 6 cathode

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Junji Aoya 1-13-1 Nihonbashi, Chuo-ku, Tokyo Inside TDK Corporation (72) Inventor Tetsuji Fujita 1-13-1 Nihonbashi, Chuo-ku, Tokyo TDK F term in the company (reference) 3K007 AB00 AB02 AB06 CA01 CB01 DA00 DA01 DB03 EB00 FA01 FA03

Claims (7)

[Claims] 1. An anode, a cathode, and one or more organic compound layers provided between these electrodes, wherein at least one of the organic compound layers is represented by the following general formula (I). Organic EL device containing a compound represented by the formula: Embedded image (In the general formula (I), R _{1 to} R ₆ each represent an aryl group,
Represents an alkyl group, an amino group or a hydrogen atom, at least one of R _{1 to} R ₃ is an aryl group, at least one of R _{4 to} R ₆ is an aryl group, and R _{7 to} R ₁₀ are each an aryl group. Represents one of a group, an alkyl group, an alkenyl group, an alkoxy group, an aryloxy group and a hydrogen atom. ) 2. The organic EL device according to claim 1, wherein at least one of the organic compound layers is a light emitting layer, and the light emitting layer contains the compound represented by the general formula (I). 3. The compound represented by the above general formula (I)
3. The organic EL device according to claim 1, which is a dopant of a host substance having a light emitting function by itself. 4. The organic EL device according to claim 3, wherein said host substance is a triarylamine derivative. 5. The organic EL device according to claim 3, wherein said host substance is a quinolinol derivative. 6. The compound according to claim 1, wherein the light-emitting layer is a mixed layer of at least one or more hole injecting and transporting compounds and at least one or more electron injecting and transporting compounds. Is the dopant of the mixed layer having a light-emitting function. 7. The organic EL device according to claim 6, wherein the hole injecting and transporting compound is a tetraaryl arylenediamine derivative and / or a triarylamine derivative, and the electron injecting and transporting compound is a quinolinol derivative.