JP4200152B2 - Organic EL device - Google Patents

Description

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

  There is a doping method as a method for obtaining an arbitrary emission color of an EL element, and there is a report (for example, Non-Patent Document 1) in which an emission color is changed from blue to green by doping a trace amount of tetracene in an anthracene crystal. is there. In addition, in an organic thin film EL element having a laminated structure, a light emitting layer is formed by mixing a small amount of a fluorescent dye that emits light emitted from a host material having a light emitting function in response to the light emission as a dopant. There has been a report (for example, Patent Document 1) in which the emission color is changed from orange to red.

  Regarding long-wavelength emission of yellow to red, as a light emitting material or a dopant material, a laser dye that oscillates red (for example, Patent Document 2), a compound that exhibits exciplex light emission (for example, Patent Document 3), a perylene compound (for example, Patent Document 4), coumarin compounds (for example, Patent Document 5), dicyanomethylene compounds (for example, Patent Document 6), thioxanthene compounds (for example, Patent Document 7), mixtures of conjugated polymers and electron transport compounds ( For example, Patent Document 8), squarylium compounds (for example, Patent Document 9), oxadiazole compounds (for example, Patent Document 10), oxynate derivatives (for example, Patent Document 11), pyrene compounds (for example, Patent Document 12) There is.

  As other light-emitting materials, condensed polycyclic aromatic compounds (for example, Patent Document 13 and Patent Document 14) are also disclosed. Also, various condensed polycyclic aromatic compounds (for example, Patent Document 15) have been proposed as dopant materials.

However, sufficient luminance and stable light emission performance are not obtained in any light emission, and further improvement in luminance or durability is desired.
Jpn. J. Appl. Phys., 10,527 (1971) Japanese Unexamined Patent Publication No. 63-264692 European Patent No. 281381 JP-A-2-255788 JP-A-3-791 JP-A-3-792 Japanese Patent Laid-Open No. 3-162481 JP-A-3-177486 JP-A-6-73374 JP-A-6-93257 JP-A-6-136359 JP-A-6-145146 JP-A-6-240246 JP-A-5-32966 JP-A-5-214334 Japanese Patent Application Laid-Open No. 5-258859

  The main object of the present invention is to provide an organic EL device having excellent durability that can emit light with sufficient luminance, particularly light emission at a long wavelength, and has good light emission performance for a long period of time.

The above object is achieved by any one of the following configurations (1) to ( 10 ).
(1) An organic EL device having at least one organic compound layer containing a compound represented by the following general formula (I).
Formula (I)
(Ar) m-L
(In the general formula (I), Ar is an alkylphenyl group or an arylphenyl group, m is 2, and L is a divalent residue derived from pentacene. )
( 2 ) The organic EL device according to any one of (1 ), wherein the organic compound layer containing the compound represented by the general formula (I) is a light emitting layer.
( 3 ) The organic EL device according to ( 2 ), wherein the light emitting layer contains a quinoline derivative.
( 4 ) The organic EL device according to ( 3 ), wherein the quinoline derivative is tris (8-quinolinolato) aluminum.
( 5 ) The organic EL according to any one of ( 2) to (4 ), wherein the light emitting layer is a mixed layer of at least one kind of hole injecting and transporting compound and at least one kind of electron injecting and transporting compound. element.
( 6 ) The organic EL device according to any one of ( 2 ) to ( 5 ), wherein the compound represented by the general formula (I) is contained in the light emitting layer at a concentration of 0.01 wt% to 20 wt%. .
( 7 ) The organic EL element according to any one of ( 2 ) to ( 6 ), which has at least one hole injection transport layer.
( 8 ) The organic EL according to ( 7 ), wherein the hole injection transport layer comprises at least one hole injection layer and at least one hole transport layer, and the light emitting layer is in contact with the hole transport layer. element.
( 9 ) The organic EL device according to any one of ( 2 ) to ( 8 ), which has at least one electron injecting and transporting layer.
( 10 ) The organic EL device according to ( 9 ), wherein the electron injection / transport layer comprises at least one electron injection layer and at least one electron transport layer, and the light emitting layer is in contact with the electron transport layer.

  In the present invention, the organic compound layer, particularly the light emitting layer, contains the compound represented by the general formula (I). Therefore, an organic EL element having a maximum emission wavelength in a wavelength range of about 460 to 700 nm, particularly a long wavelength range, can be obtained. In particular, the compound of the general formula (I) has a light emitting function in the light emitting layer as a dopant of a host material 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 it as a dopant for the mixed layer, blue to red light emission, in particular, long wavelength light emission is possible, and sufficient luminance is obtained and the light emission performance is sustained.

  Various condensed polycyclic aromatic compounds are disclosed in JP-A-63-264692, JP-A-5-32966, JP-A-5-198377, JP-A-5-214334, JP-A-5-258859, and the like. However, the structure is clearly different from the compound represented by formula (I) in the present invention.

  According to the present invention, it is possible to obtain an organic EL device having excellent durability in which long-wavelength light emission particularly from yellow to red is obtained with sufficient luminance and the light emission performance is sustained for a long time.

  Hereinafter, a specific configuration of the present invention will be described. The organic EL device of the present invention has at least one organic compound layer containing an organic compound, and at least one of the organic compound layers contains a compound represented by the general formula (I).

Formula (I)
(Ar) m-L

  In general formula (I), Ar represents an aromatic residue, m is an integer of 2 to 6, and each Ar may be the same or different.

  Examples of the aromatic residue include an aromatic hydrocarbon residue and an aromatic heterocyclic residue. The aromatic hydrocarbon residue may be any hydrocarbon group containing a benzene ring, such as a monocyclic or polycyclic aromatic hydrocarbon residue, and also includes a condensed ring and a ring assembly.

  The aromatic hydrocarbon residue preferably has a total carbon number of 6 to 30, and may have a substituent. Examples of the substituent in the case of having a substituent include an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an amino group, and a heterocyclic group. Aromatic hydrocarbon residues include phenyl, alkylphenyl, alkoxyphenyl, arylphenyl, aryloxyphenyl, alkenylphenyl, aminophenyl, naphthyl, anthryl, pyrenyl, perylenyl, etc. Can be mentioned. Further, it may be an arylalkynyl group derived from an alkynylarene (arylalkyne).

  The aromatic heterocyclic residue preferably contains O, N, or 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.

  Ar is preferably an aromatic hydrocarbon residue, particularly preferably a phenyl group, an alkylphenyl group, an arylphenyl group, an alkenylphenyl group, an aminophenyl group, a naphthyl group, or an arylalkynyl group.

  The alkylphenyl group preferably has 1 to 10 carbon atoms in the alkyl moiety, and the alkyl group may be linear or branched, and may be a methyl group, an ethyl group, (n, i ) -Propyl group, (n, i, sec, tert) -butyl group, (n, i, neo, tert) -pentyl group, (n, i, neo) -hexyl group, and other alkyl groups, and these The substitution position of the alkyl group 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.

  As the arylphenyl group, those in which the aryl moiety is a phenyl group are preferable, and such a phenyl group may be substituted, and the substituent at this time is preferably an alkyl group, specifically, The alkyl group illustrated in the alkylphenyl group can be mentioned. Furthermore, the aryl moiety may be a phenyl group substituted with 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, and terphenylyl group.

  The alkenylphenyl group preferably has 2 to 20 carbon atoms in the alkenyl moiety, and the alkenyl group is preferably a triarylalkenyl group, such as a triphenylvinyl group, a tolylvinyl group, or a tribiphenylvinyl group. It is done. Specific examples of such an alkenylphenyl group include a triphenylvinylphenyl group.

  As the aminophenyl group, those in which the amino moiety is a diarylamino group are preferable, and examples of the arylamino group include a diphenylamino group and a phenyltolylamino group. Specific examples of such an aminophenyl group include a diphenylaminophenyl group and a phenyltolylaminophenyl group.

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

  As the arylalkynyl group, those having a total carbon number of 8 to 20 are preferable, and phenylethynyl group, tolylethynyl group, biphenylylethynyl group, naphthylethynyl group, diphenylaminophenylethynyl group, N-phenyltolylaminophenylethynyl group, phenylpropynyl group. Nyl group etc. are mentioned.

  L in the general formula (I) represents a m (2-6) -valent residue of a condensed polycyclic aromatic having 3 to 10 rings, preferably 3 to 6 rings. A condensed ring refers to a cyclic structure formed by a carbocycle, a heterocycle, or the like in which two or more atoms among ring constituent atoms are bonded and shared with other rings. Examples of the condensed polycyclic aromatic include condensed polycyclic aromatic hydrocarbons and condensed polycyclic aromatic heterocycles.

  Examples of the condensed polycyclic aromatic hydrocarbon include anthracene, phenanthrene, naphthacene, pyrene, chrysene, triphenylene, benzo [c] phenanthrene, benzo [a] anthracene, pentacene, perylene, dibenzo [a, j] anthracene, dibenzo [a, h] anthracene, benzo [a] naphthacene, hexacene, anthanthrene and the like.

  Examples of the condensed polycyclic aromatic heterocycle include naphtho [2,1-f] isoquinoline, α-naphthaphenanthridine, phenanthrooxazole, quinolino [6,5-f] quinoline, benzo [b] thiophantrene, Examples include benzo [g] thiophantolene, benzo [i] thiophantolene, and benzo [b] thiophanthraquinone.

  In particular, condensed polycyclic aromatic hydrocarbons are preferred, and L is preferably a 2-6 valent, further 2-4 valent residue derived from these condensed polycyclic aromatic hydrocarbons.

  Specific examples of such a condensed polycyclic aromatic divalent to hexavalent residue L are shown below.

  The condensed polycyclic aromatic divalent to hexavalent residue represented by L may further have a substituent, but is usually preferably unsubstituted.

  In particular, L is preferably a divalent to hexavalent, particularly divalent to tetravalent residue derived from naphthacene, pentacene or hexacene in which a benzene ring is linearly condensed. However, when L is a tetravalent residue derived from naphthacene, a 5,6,11,12-naphthacene-tetrayl group, the four Ars do not simultaneously become a phenyl group.

  L is preferably a divalent to hexavalent residue derived from anthracene, more preferably a divalent to tetravalent residue. However, when L is a divalent or trivalent residue derived from anthracene, at least one of two or three Ars is a residue derived from an alkynylarene (arylalkyne). Furthermore, it is preferable that two or more of Ar are such residues. In particular, L is preferably a trivalent residue derived from anthracene, and the compound of general formula (I) is such L, wherein two Ar are an arylalkynyl group, one Ar Is preferably a bis (arylalkynyl) anthryl group, particularly preferably represented by the general formula (I-1).

Formula (I-1)
(Ar ₁ ) ₂ -L ₁ -L _2- (Ar ₂ ) ₂

In the formula, L ₁ and L ₂ each represent a trivalent residue derived from anthracene, which are usually the same, but may be different. Ar ₁ and Ar ₂ each represent an arylalkynyl group, which are usually the same but may be different. The binding position of the arylalkynyl group in the anthracene is preferably the 9th and 10th positions of the anthracene, and the anthracene is preferably bonded in the 1st position or the 2nd position. Specific examples of the arylalkynyl group include those described above.

Specific examples of the compound represented by formula (I) are shown below, but the present invention is not limited to these. Among them, chemical formula 4, chemical formula 7, chemical formula 10, chemical formula 13 and chemical formula 15 are general formulas, and chemical formula 5, chemical formula 6, chemical formula 8, chemical formula 9, chemical formula 11, chemical formula 12, chemical formula 12, chemical formula 14, chemical formula 16, and chemical formula 16 have these. A combination of R _{1 and the} like is shown. In addition, in the chemical formula 5 and the like, those collectively shown as R _{1 to} R _{4 and} the like are indicated as H unless otherwise specified, and when all are H, they are indicated as H.

The compound represented by the general formula (I) is a method in which an aromatic compound having a quinone structure is reacted with a Grignard reagent or a lithiation reagent and further reduced (Maulding, DR, et al., J. Org. Chem., 34 1734 (1969) and Hanhela, PJ, et al., Aust. J. Chem., 34, 1687 (1981), etc.) or according to this method. In addition, the compound represented by the general formula (I-1) is a method in which a halogenated bis (arylalkynyl) anthracene compound is coupled with Ni (cod) ₂ [cod: 1,5-cyclooctadiene]. Can be synthesized.

  A synthesis example is shown below.

Synthesis example 1
Synthesis of 5,12-bis (m-biphenylyl) naphthacene (Compound No. 1-1) A nitrogen-substituted 200 ml Schlenk flask was charged with 2.58 g (10 mmol) of 5,12-naphthacenequinone and 100 ml of toluene. To this solution, a toluene / ether solution of 3.5 g (21.8 mmol) of m-biphenyllithium separately synthesized from m-bromobiphenyl and butyllithium was added dropwise over 1 hour. After dropping, the mixture was stirred at room temperature for 12 hours and poured into ice water. This reaction solution was extracted 5 times with toluene, washed with water, dried over magnesium sulfate, the solvent was distilled off, and the residue was washed with methanol and hexane to obtain 3.5 g of a diol.

  Next, 3.5 g of this diol and 100 ml of acetic acid were charged into a 300 ml flask and dissolved. To this solution, a solution of 1.0 g of tin (II) chloride dissolved in 10 ml of hydrochloric acid was added dropwise, stirred at 100 ° C. for 1 hour, cooled to room temperature, this reaction solution was extracted with 400 ml of toluene, and then added with water. Washed twice and dried over magnesium sulfate. After distilling off the solvent, it was purified 3 times on a silica gel column using toluene and hexane as extraction solvents while shielding from light, and then recrystallized from toluene to obtain 3.0 g of orange crystals. When 1 g of this crystal was purified by sublimation, an orange crystal (0.6 g) was obtained.

Synthesis example 2
Synthesis of 5,12-bis (o-biphenylyl) naphthacene (Compound No. 1-2) A nitrogen-substituted 200 ml Schlenk flask was charged with 2.58 g (10 mmol) of 5,12-naphthacenequinone and 100 ml of toluene. To this solution was added dropwise a toluene / ether solution of 3.5 g (21.8 mmol) of o-biphenyllithium separately synthesized from o-iodobiphenyl and butyllithium over 1 hour. After dropping, the mixture was stirred at room temperature for 12 hours and poured into ice water. This reaction solution was extracted 5 times with toluene, washed with water, dried over magnesium sulfate, the solvent was distilled off, and the residue was washed with methanol and hexane to obtain 3.5 g of a diol.

  Next, 3.5 g of this diol and 100 ml of acetic acid were charged into a 300 ml flask and dissolved. To this solution, a solution of 1.0 g of tin (II) chloride dissolved in 10 ml of hydrochloric acid was added dropwise, stirred at 100 ° C. for 1 hour, cooled to room temperature, this reaction solution was extracted with 600 ml of toluene, and then extracted with water. Washed twice and dried over magnesium sulfate. After distilling off the solvent, the mixture was purified three times on a silica gel column using toluene and hexane as extraction solvents while shielding from light, and then recrystallized from toluene to obtain 2.5 g of orange crystals. When 1 g of this crystal was purified by sublimation, an orange crystal (0.6 g) was obtained.

Synthesis example 3
Synthesis of 5,12-bis (4-n-butylphenyl) naphthacene (Compound No. 1-3) A nitrogen-substituted 200 ml Schlenk flask was charged with 2.58 g (10 mmol) of 5,12-naphthacenequinone and 100 ml of toluene. To this solution, a toluene / ether solution of 3.0 g (21.2 mmol) of 4-n-butylphenyllithium separately synthesized from 4-n-butyliodobenzene and butyllithium was added dropwise over 1 hour. After dropping, the mixture was stirred at room temperature for 12 hours and poured into ice water. This reaction solution was extracted 5 times with toluene, washed with water, dried over magnesium sulfate, the solvent was distilled off, and the residue was washed with methanol and hexane to obtain 3.0 g of a diol.

Next, in a 300 ml flask, 3.0 g of this diol and 100 ml of acetic acid were added and dissolved. To this solution, a solution of 1.0 g of tin (II) chloride dissolved in 10 ml of hydrochloric acid was added dropwise, stirred at 100 ° C. for 1 hour, cooled to room temperature, this reaction solution was extracted with 400 ml of toluene, and then added with water. Washed twice and dried over magnesium sulfate. After the solvent was distilled off, the residue was purified three times on a silica gel column using toluene and hexane as extraction solvents and then recrystallized from toluene to obtain 3.0 g of orange crystals. When 1 g of this crystal was purified by sublimation, an orange crystal (0.8 g) was obtained.
Mass spectrometry: m / e 492 (M +)
Infrared absorption spectrum: Fig. 2
NMR spectrum: FIG.

Synthesis example 4
Synthesis of 6,13-bis (o-biphenylyl) pentacene (Compound No. 2-1) A nitrogen-substituted 200 ml Schlenk flask was charged with 3.08 g (10 mmol) of 6,13-pentacenequinone and 100 ml of toluene. To this solution was added dropwise a toluene / ether solution of 3.5 g (21.8 mmol) of o-biphenyllithium separately synthesized from o-bromobiphenyl and butyllithium over 1 hour. After dropping, the mixture was stirred at room temperature for 12 hours and poured into ice water. The reaction solution was filtered, and the residue was washed with water and toluene to obtain 4.0 g of a diol.

Next, 4.0 g of this diol and 100 ml of acetic acid were charged into a 300 ml flask and dissolved. To this solution, a solution of 1.0 g of tin (II) chloride dissolved in 10 ml of hydrochloric acid was added dropwise, stirred at 100 ° C. for 1 hour, cooled to room temperature, this reaction solution was extracted with 400 ml of toluene, and then added with water. Washed twice and dried over magnesium sulfate. After the solvent was distilled off, the residue was purified three times on a silica gel column using toluene and hexane as extraction solvents and then recrystallized from toluene to obtain 2.0 g of blue-violet crystals. Sublimation purification of 0.8 g of this crystal gave brown purple crystals (0.3 g and 0.1 g).
Mass spectrometry: m / e 583 (M +)
Infrared absorption spectrum: Fig. 4
NMR spectrum: FIG.

Synthesis example 5
Synthesis of 6,13-bis (m-biphenylyl) pentacene (Compound No. 2-2) A nitrogen-substituted 200 ml Schlenk flask was charged with 3.08 g (10 mmol) of 6,13-pentacenequinone and 100 ml of toluene. To this solution, a toluene / ether solution of 3.5 g (21.8 mmol) of m-biphenyllithium separately synthesized from m-bromobiphenyl and butyllithium was added dropwise over 1 hour. After dropping, the mixture was stirred at room temperature for 12 hours and poured into ice water. After filtering this reaction solution, the residue was washed with water and toluene to obtain 5.0 g of a diol.

  Next, in a 300 ml flask, 5.0 g of this diol and 100 ml of acetic acid were added and dissolved. To this solution, a solution of 1.0 g of tin (II) chloride dissolved in 10 ml of hydrochloric acid was added dropwise, stirred at 100 ° C. for 1 hour, cooled to room temperature, and the reaction solution was extracted with 400 ml of toluene and 200 ml of chloroform. Washed 5 times with water and dried over magnesium sulfate. After the solvent was distilled off, the residue was purified three times on a silica gel column using toluene and hexane as extraction solvents, and then recrystallized from toluene to obtain 3.0 g of blue-violet crystals. Sublimation purification of 1 g of this crystal gave brown purple crystals (0.6 g).

Synthesis Example 6
Synthesis of 6,13-bis (4-n-butylphenyl) pentacene (Compound No. 2-3) A nitrogen-substituted 200 ml Schlenk flask was charged with 3.08 g (10 mmol) of 6,13-pentacenequinone and 100 ml of toluene. To this solution, a toluene / ether solution of 3.0 g (21.2 mmol) of 4-n-butylphenyllithium separately synthesized from 4-n-butyliodobenzene and butyllithium was added dropwise over 1 hour. After dropping, the mixture is stirred at room temperature for 12 hours, poured into ice water, extracted with toluene, washed with water three times, dried over magnesium sulfate, the solvent is distilled off, the solid is washed with methanol, and washed with a silica gel column. After purification, 4.0 g of a diol was obtained.

  Next, 4.0 g of this diol and 100 ml of acetic acid were charged into a 300 ml flask and dissolved. To this solution, a solution of 1.0 g of tin (II) chloride dissolved in 10 ml of hydrochloric acid was added dropwise, stirred at 100 ° C. for 1 hour, cooled to room temperature, this reaction solution was extracted with 400 ml of toluene, and then added with water. This was washed with a 10% aqueous sodium hydrogen carbonate solution and dried over magnesium sulfate. After the solvent was distilled off, toluene and hexane were used as extraction solvents for purification on a silica gel column three times to obtain 3.0 g of blue-violet crystals. Sublimation purification of 1 g of this crystal gave brown purple crystals (0.7 g).

Synthesis example 7
Synthesis of 5,7,12,14-tetrakis (m-biphenylyl) pentacene (Compound No. 2-5) In a nitrogen-substituted 200 ml Schlenk flask, 3.38 g (10 mmol) of 5,7,12,14-pentacentetron and toluene 100 ml was charged. To this solution was added dropwise a toluene / ether solution of 7.0 g (43.7 mmol) of m-biphenyllithium separately synthesized from m-bromobiphenyl and butyllithium over 1 hour. After dropping, the mixture was stirred at room temperature for 12 hours and poured into ice water. The reaction solution was filtered, and the solid was washed with water and toluene to obtain 5.5 g of a diol.

  Next, 5.5 g of this diol and 100 ml of acetic acid were put into a 300 ml flask and dissolved. To this solution, a solution of 1.0 g of tin (II) chloride dissolved in 10 ml of hydrochloric acid was added dropwise, stirred at 100 ° C. for 1 hour, cooled to room temperature, 200 ml of toluene was added to the reaction solution, and 5 times with water. Washed. This reaction solution was filtered, further washed with water and toluene, and recrystallized from chloroform to obtain 3.0 g of blue-violet crystals. Sublimation purification of 1 g of this crystal gave brown purple crystals (0.6 g).

Synthesis example 8
Synthesis of 5,7,12,14-tetrakis (4-n-butylphenyl) pentacene (Compound No. 2-6) In a nitrogen-substituted 200 ml Schlenk flask, 3.38 g (10 mmol) of 5,7,12,14-pentacentetron ) And 100 ml of toluene. To this solution was added dropwise a toluene / ether solution of 6.0 g (42.5 mmol) of 4-n-butylphenyllithium separately synthesized from 4-n-butylbenzene and butyllithium over 1 hour. After dropping, the mixture was stirred at room temperature for 12 hours, then poured into ice water and extracted with toluene. The reaction solution was washed with water and dried over magnesium sulfate, and the solvent was distilled off to obtain 6.5 g of a diol.

  Next, 6.5 g of this diol and 100 ml of acetic acid were charged into a 300 ml flask and dissolved. To this solution, a solution of 1.0 g of tin (II) chloride dissolved in 10 ml of hydrochloric acid was added dropwise, stirred at 100 ° C. for 1 hour, cooled to room temperature, 800 ml of toluene was added to the reaction solution, and 5 times with water. After washing and drying with magnesium sulfate, the solvent was distilled off to obtain blue-violet crystals. This blue-violet crystal was purified by a silica gel column three times using hexane and toluene as extraction solvents, and recrystallized from toluene / hexane to obtain 3.0 g of blue-violet crystal. When 1 g of this crystal was purified by sublimation, blue-violet crystal (0.6 g) was obtained.

Synthesis Example 9
Synthesis of Compound No. 4-1 Bis (1,5-cyclooctadiene) nickel (Ni (cod) ₂ ) 0.37 g (1.35 mmol), 2,2′-bipyridine 0.20 g (1.28 mmol) 1,5-cyclooctadiene (0.20 ml) is mixed with 20 ml of N, N-dimethylformamide in a nitrogen atmosphere, and further 1.23 g (2.74 mmol) of 2-chloro-9,10-bis (phenylethynyl) anthracene. ) And stirred at 60 ° C. for 24 hours. This reaction solution was poured into a 1N aqueous hydrochloric acid solution, extracted with toluene and chloroform, washed with water, and dried over magnesium sulfate. The obtained product was reprecipitated with acetone, recrystallized three times from chloroform, and purified on a silica column using toluene as an extraction solvent to obtain 0.8 g of an orange solid. The obtained orange solid 0.8 g was purified by sublimation to obtain 0.52 g of orange solid.

Synthesis Example 10
Synthesis of Compound No. 5-1. Bis (1,5-cyclooctadiene) nickel (Ni (cod) ₂ ) 0.37 g (1.35 mmol), 2,2′-bipyridine 0.20 g (1.28 mmol) 1,5-cyclooctadiene 0.20 ml is mixed with 20 ml of N, N-dimethylformamide in a nitrogen atmosphere, and 1.23 g (3.00 mmol) of 1-chloro-9,10-bis (phenylethynyl) anthracene is added. ) And stirred at 60 ° C. for 24 hours. This reaction solution was poured into a 1N aqueous hydrochloric acid solution, extracted with toluene and chloroform, washed with water, and dried over magnesium sulfate. The obtained product was reprecipitated with acetone, recrystallized from chloroform three times, and purified on a silica column using toluene as an extraction solvent to obtain 0.53 g of an orange solid. 0.5 g of the obtained orange solid was purified by sublimation to obtain 0.23 g of an orange solid having yellow fluorescence.
Mass spectrometry: m / e 754 (M +)

  The compounds of the general formula (I) have some data shown above, but can be identified by elemental analysis, mass spectrometry, infrared absorption spectrum (IR), 1H nuclear magnetic resonance spectrum (NMR) and the like.

  These compounds have a molecular weight of about 400 to 1500, a melting point of about 100 to 400 ° C., and a glass transition temperature of about 80 to 250 ° C. For this reason, the amorphous state which is transparent and stable even at room temperature or higher is formed by ordinary vacuum deposition or the like, and is obtained as a smooth and good film, which is maintained for a long period of time. Moreover, it can be made into a thin film by itself without using a binder resin.

  The compound of general formula (I) may use only 1 type, or may use 2 or more types together.

  As a structural example of the organic EL device of the present invention having at least one organic compound layer containing the compound of the general formula (I), the one shown in FIG. The organic EL element 1 shown in the figure has an anode 3, a hole injection / transport layer 4, a light emitting layer 5, an electron injection / transport layer 6, and a cathode 7 in this order on a substrate 2.

  The light emitting layer has a hole and electron injection function, a transport function thereof, 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. The hole injecting and transporting layer has the function of facilitating the injection of holes from the anode, the function of transporting holes and the function of blocking electrons, and the electron injecting and transporting layer facilitates the injection of electrons from the cathode. These layers have the function of transporting electrons, transporting electrons, and blocking holes. These layers increase and confine holes and electrons injected into the light-emitting layer, optimize the recombination region, and emit light. Improve efficiency. The hole injecting and transporting layer and the electron injecting and transporting layer are provided as necessary in consideration of the height of each function of the hole injection, hole transport, electron injection and electron transport of the compound used for the light emitting layer. For example, when the hole injection / transport function or electron injection / transport function of the compound used in the light-emitting layer is high, the light-emitting layer is not provided with the hole injection / transport layer or the electron injection / transport layer, but the hole injection / transport layer or the electron injection It can be set as the structure which serves 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 injecting and transporting layer and the electron injecting and transporting layer may be separately provided in the layer having an injection function and the layer having a transport function, respectively.

  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 may vary depending on the formation method, but is usually about 5 to 1000 nm, and particularly 10 to 200 nm. preferable.

  The thickness of the hole injecting and transporting layer and the thickness of the electron injecting and transporting layer may be about the same as the thickness of the light emitting layer or about 1/10 to 10 times depending on the design of the recombination / light emitting region. When the injection layer and the transport layer for electrons or holes are separated, the injection layer is preferably 1 nm or more, and the transport layer is preferably 20 nm or more. In this case, the upper limit of the thickness of the injection layer and the transport layer is usually about 100 nm for the injection layer and about 1000 nm for the transport layer. Such a film thickness is the same when two injection transport layers are provided.

  In addition, the recombination region and light emission can be controlled by controlling the film thickness while considering the carrier mobility and carrier density (determined by the ionization potential and electron affinity) of the combined light-emitting layer, electron injection transport layer, and hole injection transport layer. The region can be designed freely, and it is possible to design the light emission color, control the light emission luminance / light emission spectrum by the interference effect of both electrodes, and control the spatial distribution of light emission.

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

  In the present invention, the fluorescent layer may contain other fluorescent material in addition to the compound of the general formula (I). Examples of such a fluorescent substance include at least one selected from compounds such as those disclosed in JP-A 63-264692, such as quinacridone, rubrene, and styryl dyes. Further, quinoline derivatives such as metal complex dyes having 8-quinolinol or a derivative thereof such as tris (8-quinolinolato) aluminum as a ligand, tetraphenylbutadiene, anthracene, perylene, coronene, 12-phthaloperinone derivatives, and the like can be given. Furthermore, a phenylanthracene derivative of Japanese Patent Application No. 6-110569, a tetraarylethene derivative of Japanese Patent Application No. 6-114456, and the like are also included.

  The content of the compound of general formula (I) in the light emitting layer is preferably 0.01 wt% or more, more preferably 0.1 wt% or more.

  In particular, the compound of the general formula (I) is preferably used in combination with a host material, particularly a host material 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 wt%, more preferably 0.1 to 15 wt%. When used in combination with a host material, the emission wavelength characteristic of the host material can be changed, light emission shifted to a longer wavelength can be achieved, and the light emission efficiency and stability of the device can be improved.

  The host material is preferably a quinoline derivative, and more preferably an aluminum complex having 8-quinolinol or a derivative thereof as a ligand. Examples of such aluminum complexes are those disclosed in JP-A-63-264692, JP-A-3-255190, JP-A-5-70733, JP-A-5-258859, JP-A-6-215874, and the like. Can be mentioned.

  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-quinolinolato aluminum, tris (5,7-dibromo-8-hydroxyquinolinolato) aluminum, poly [zinc (II) -bis (8-hydroxy-5-quinolinyl) methane], Etc.

  In addition to 8-quinolinol or a derivative thereof, an aluminum complex having another ligand may be used, and examples thereof include bis (2-methyl-8-quinolinolato) (phenolato) aluminum (III). Bis (2-methyl-8-quinolinolato) (ortho-cresolato) aluminum (III), bis (2-methyl-8-quinolinolato) (meta-cresolato) aluminum (III), bis (2-methyl-8-quinolinolato) ( Para-cresolato) aluminum (III), bis (2-methyl-8-quinolinolato) (ortho-phenylphenolato) aluminum (III), bis (2-methyl-8-quinolinolato) (meta-phenylphenolato) aluminum ( III), bis (2-methyl-8-quinolinolato) (para-phenylphenolato) aluminum (III), bis ( -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-trimethylphenola) ) Aluminum (III), bis (2-methyl-8-quinolinolato) (2,3,5,6-tetramethylphenolato) Aluminum (III), bis (2-methyl-8-quinolinolato) (1-naphtholato) Aluminum (III), bis (2-methyl-8-quinolinolato) (2-naphtholato) aluminum (III), 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 -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-naphtholato) aluminum (III) and the like.

  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-methoxyquinolino) Lato) aluminum (III), bis (5-cyano-2-methyl-8-quinolinolato) aluminum (III) -μ-oxo-bis (5-cyano-2-methyl-8-quinolinolato) a Luminium (III), bis (2-methyl-5-trifluoromethyl-8-quinolinolato) aluminum (III) -μ-oxo-bis (2-methyl-5-trifluoromethyl-8-quinolinolato) aluminum (III) Etc.

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

  As other host substances, a phenylanthracene derivative described in Japanese Patent Application No. 6-110568 and a tetraarylethene derivative described in Japanese Patent Application No. 6-114456 are also preferable.

  The phenylanthracene derivative is represented by the general formula (II).

Formula (II)
A ¹ -L ¹ -A ²

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

The monophenylanthryl group or diphenylanthryl group represented by A ¹ or A ² may be unsubstituted or may have a substituent. In the case of having a substituent, examples of the substituent include an alkyl group, aryl Group, alkoxy group, aryloxy group, amino group and the like, and these substituents may be further substituted. The substitution position of such a substituent is not particularly limited, but is preferably not a anthracene ring but a phenyl group bonded to the anthracene ring. Moreover, it is preferable that the bonding position of the phenyl group in the anthracene ring is the 9th or 10th position of the anthracene ring.

In the general formula (II), L1 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 are directly formed. The connected thing is mentioned. 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 may be ^{one in} which two or more arylene groups are linked via an alkylene group, —O—, —S—, or —NR—. 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, an aryl group is preferable, and in addition to the above phenyl group, A ¹ and A ² may be used, and further, A ¹ or A ² may be substituted on the phenyl group. The alkylene group is preferably a methylene group or an ethylene group. Specific examples of such an arylene group are shown below.

  Further, the tetraarylethene derivative is represented by Chemical Formula 22.

In Chemical Formula 22, Ar ¹ , Ar ² and Ar ³ each represent an aromatic residue, and these may be the same or different.

Examples of the aromatic residue represented by Ar ^{1 to} Ar ³ 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 preferably has a total carbon number of 6 to 30, and may have a substituent. In the case of having a substituent, examples of the substituent include an alkyl group, an aryl group, an alkoxy group, an aryloxy group, and an amino group. Examples of the aromatic hydrocarbon group include a phenyl group, an alkylphenyl group, an alkoxyphenyl group, an arylphenyl group, an aryloxyphenyl group, an aminophenyl group, a biphenyl group, a naphthyl group, an anthryl group, a pyrenyl group, and a perylenyl group. It is done.

  The aromatic heterocyclic group preferably includes 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 ^{1 to} Ar ³ , a phenyl group is particularly preferable.

  n is an integer of 2 to 6, and preferably an integer of 2 to 4.

L ² represents an n-valent aromatic residue, particularly a 2-6 valent residue derived from an aromatic hydrocarbon, an aromatic heterocycle, an aromatic ether or an aromatic amine, particularly a 2-4 valent residue. Preferably there is. These aromatic residues may further have a substituent, but are preferably unsubstituted.

  As the light emitting layer using the compound of the general formula (I), in addition to the above-mentioned host substance, a mixed layer of at least one kind of hole injecting and transporting compound and at least one kind of electron injecting and transporting compound It is also preferable that the compound of general formula (I) is contained as a dopant in the mixed layer. The content of the compound of general formula (I) in such a mixed layer is preferably 0.01 to 20 wt%, more preferably 0.1 to 15 wt%.

  In the mixed layer, a carrier hopping conduction path is formed, so that each carrier moves in a polar dominant substance, and carrier injection of the opposite polarity is less likely to occur. However, by including the compound of general formula (I) in such a mixed layer, the emission wavelength characteristic of the mixed layer itself can be changed, and the emission wavelength is shifted to a longer wavelength. In addition, the emission intensity is increased and the stability of the device is improved.

  The hole injecting and transporting compound and the electron injecting and transporting compound used in the mixed layer may be selected from a compound for a hole injecting and transporting layer and a compound for an electron injecting and transporting layer described later. Among these, as the electron injecting and transporting compound, it is preferable to use a quinoline derivative, a metal complex having 8-quinolinol or a derivative thereof as a ligand, particularly tris (8-quinolinolato) aluminum.

  The mixing ratio in this case depends on the carrier mobility, but the weight ratio of the compound having a hole injecting and transporting compound / the compound having an electron injecting and transporting function is 30/70 to 70/30, more preferably 40/60 to 60 / 40, especially about 50/50).

  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, specifically 1 to 85 nm, more preferably 5 to 60 nm, In particular, the thickness is preferably 5 to 50 nm.

  In addition, as a method for forming the mixed layer, co-evaporation is preferably performed by evaporating from different evaporation sources, but when the vapor pressure (evaporation temperature) is the same or very close, the mixture is previously mixed in the same evaporation board, It can also be deposited. In the mixed layer, it is preferable that the compounds are uniformly mixed, but in some cases, the compounds may be present in an island shape. In general, the light emitting layer is formed to have a predetermined thickness by depositing an organic fluorescent material or coating the light emitting layer by dispersing it in a resin binder.

  In the present invention, an electron injecting and transporting layer may be provided. For the electron injecting and transporting layer, quinoline derivatives such as organometallic complexes having 8-quinolinol or its derivatives such as tris (8-quinolinolato) aluminum 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 or the like. The electron injecting and transporting layer may be formed by vapor deposition or the like as in the light emitting layer.

  When the electron injecting and transporting layer is divided into an electron injecting layer and an electron transporting layer, a preferred combination can be selected from the compounds for the electron injecting and transporting layer. At this time, it is preferable to laminate in the order of a compound layer having a large electron affinity value 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.

  In the present invention, a hole injection transport layer may be provided. The hole injecting and transporting layer includes various organic compounds described in JP-A-63-295695, JP-A-2-191694, JP-A-3-792, etc., for example, aromatic tertiary amine, hydrazone. Derivatives, carbazole derivatives, triazole derivatives, imidazole derivatives, oxadiazole derivatives having an amino group, polythiophene, and the like can be used. These compounds may be used as a mixture of two or more kinds, or may be used in a stacked manner.

  When the hole injecting and transporting layer is divided into 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 laminate in order of a compound layer having a small ionization potential from the anode (ITO or the like) side, and 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. Moreover, it is preferable to use a compound having a good thin film property on the anode surface. The relationship between the ionization potential and the stacking order is the same when two or more hole injection / transport layers are provided. By adopting such a stacking order, the drive voltage is lowered, and the occurrence of current leakage and the generation / growth of dark spots can be prevented. In addition, in the case of forming an element, since vapor deposition is used, a thin film of about 1 to 10 nm can be made uniform and pinhole-free, so that the ion injection potential is small in the hole injection layer and the visible portion has absorption. Even if such a compound is used, it is possible to prevent a decrease in efficiency due to a change in color tone of light emission and reabsorption.

  When laminating two or more hole injection / transport layers, or when laminating a hole injection layer and a hole transport layer, a polythiophene with good thin film properties is placed on the anode on the hole injection layer or the first hole injection. It is preferable to use it for a transport layer, and an aromatic tertiary amine such as N, N′-bis (m-tolyl) -N, N′-diphenyl-1,1′-biphenyl-4,4′-diamine is used as a hole. It is preferably used for the transport layer or the second hole injection transport layer.

As such a polythiophene, those described in EP 634118 A1 (Japanese Patent Application No. Hei 6-17312) are preferably used, and one of thiophene-2,5-diyl and thiophene-2,4-diyl is used as a polymer structural unit. preferably those containing above, even repeating units are the same a homopolymer, may be a repeating unit different copolymers, the weight average molecular weight M _W is about 300 to 10,000, polymerization degree of 4 to 100 Degree. Specific examples include poly (thiophene-2,5-diyl), poly (thiophene-2,4-diyl), (thiophene-2,5-diyl)-(thiophene-2,4-diyl) copolymer, and the like. Of these, poly (thiophene-2,5-diyl) is preferred. Polythiophene may be used alone or in combination of two or more. The polythiophene used in the present invention has a melting point of 300 ° C. or higher, or has no melting point, and a high-quality film in an amorphous state or a microcrystalline state can be obtained by vacuum deposition.

  On the other hand, 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-methyl) Phenylamino) 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] benzidi Etc. The.

  In the present invention, the organic compound layer may contain a singlet oxygen quencher. Such quenchers include rubrene, nickel complexes, diphenylisobenzofuran, tertiary amines and the like.

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

  In order to cause the organic EL element to emit light, at least one of the electrodes needs to be transparent or translucent, and the cathode material is limited as described above. Therefore, the transmittance of emitted light is preferably 80%. It is preferable to determine the material and thickness of the anode so as to achieve the above. Specifically, for example, ITO, SnO2, Ni, Au, Pt, Pd, polypyrrole doped with a dopant, or the like is preferably used for the anode. The thickness of the anode is preferably about 10 to 500 nm. In addition, the driving voltage needs to be low in order to improve the reliability of the device, and preferable examples include ITO of 10 to 30Ω / □ or 10Ω / □ or less (usually 0.1 to 10Ω / □). .

  The substrate material is not particularly limited, but in the illustrated example, a transparent or translucent material such as glass or resin is used 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.

  Note that when an opaque material is used for the substrate, the stacking order shown in FIG. 1 may be reversed.

  Next, the manufacturing method of the organic EL element of this invention is demonstrated.

  The cathode and the anode are preferably formed by vapor deposition such as vapor deposition or sputtering.

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

The conditions for vacuum deposition are not particularly limited, but it is preferable that the degree of vacuum is 10 ⁻³ Pa or less and the deposition rate is about 0.1 to 1 nm / sec. Moreover, it is preferable to form each layer continuously in a vacuum. If formed continuously in a vacuum, impurities can be prevented from adsorbing to the interface of each layer, so that high characteristics can be obtained. In addition, the driving voltage of the element can be lowered.

  In the case of using a vacuum deposition method for forming each of these layers, when a plurality of compounds are contained in one layer, it is preferable to co-deposit each boat containing the compounds by controlling the temperature individually. Vapor deposition may be performed. In addition, a solution coating method (spin coating, dip, casting, etc.), a Langmuir-Blodget (LB) method, or 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 element of the present invention is usually used as a direct current drive type EL element, but can also be alternating current driven or pulse driven. The applied voltage is usually about 2 to 20V.

  Hereinafter, specific examples of the present invention will be shown to describe the present invention in more detail.

[Example 1]
A glass substrate having an ITO transparent electrode (anode) having a thickness of 200 nm was subjected to ultrasonic cleaning using a neutral detergent, acetone, and ethanol. The substrate was lifted from boiling ethanol, dried, washed with UV / O ₃ , fixed to a substrate holder of a vacuum deposition apparatus, and the vacuum chamber was depressurized to 1 × 10 ⁻⁴ Pa or less.

  First, poly (thiophene-2,5-diyl) was deposited to a thickness of about 10 nm at a deposition rate of about 0.1 nm / sec to form a hole injection layer. Next, N, N′-bis (m-tolyl) -N, N′-diphenyl-1,1′-biphenyl-4,4′-diamine (hereinafter referred to as TPD) was deposited at a deposition rate of 0.1 to 0.2 nm. The film was deposited at a thickness of about 65 nm at / sec to form a hole transport layer.

  Then, while maintaining the reduced pressure, tris (8-quinolinolato) aluminum (hereinafter referred to as Alq3) and 6,13-bis (o-biphenylyl) pentacene (compound No. 2-1) were deposited at a deposition rate of 0.1 to 0, respectively. Co-evaporated to a thickness of about 20 nm at 2 nm / sec and 0.0005 to 0.001 nm / sec (0.542 wt%) to form a light emitting layer.

  Next, Alq3 was deposited at a deposition rate of 0.1 to 0.2 nm / sec to a thickness of about 30 nm to form an electron injecting and transporting layer.

  Furthermore, while maintaining the reduced pressure state, Mg and Ag are deposited to a total thickness of about 200 nm at a deposition rate of 0.1 to 0.2 nm / sec and 0.02 to 0.04 nm / sec (weight ratio 10: 1), respectively. Co-evaporation was used as a cathode to obtain an EL element.

When a DC voltage of 8 V was applied to the EL element, a current flowed about 90 mA / cm ² , and a light emission luminance of 1100 cd / m ² and a light emission efficiency of 0.51 m / W were obtained. The emission color was yellow, the peak wavelengths were 630 nm, 680 nm and 515 nm, and the CIE chromaticity coordinates were x = 0.45 and y = 0.46. The device was continuously driven at a constant current density of 10 mA / cm ^{2 in} a dry atmosphere. Initially, it was 110 cd / m ² at 6.2 V, the luminance half-life was about 500 hours, and the drive voltage increase during that period was 2.9 V.

  When the light emitting layer was composed only of Alq3, the emission color was green and the peak wavelength was 510 nm.

[Example 2]
Alq3 and Compound No. 2-1 were co-deposited to a total thickness of about 21 nm at a deposition rate of 0.1 to 0.2 nm / sec and 0.003 to 0.007 nm / sec (3.40 wt%), respectively, to emit light. An EL element was obtained in the same manner as in Example 1 except that the layer was used.

When a DC voltage of 10 V was applied to the EL element, a current flowed about 215 mA / cm ² , and a light emission luminance of 530 cd / m ² and a light emission efficiency of 0.081 m / W were obtained. The emission color was orange, the peak wavelengths were 630 nm and 685 nm, and the CIE chromaticity coordinates were x = 0.57 and y = 0.38. The device was continuously driven at a constant current density of 10 mA / cm ^{2 in} a dry atmosphere. Initially, it was 22 cd / m ² at 6.8 V, the luminance half-life was about 200 hours, and the drive voltage increase during that period was 1.5 V.

[Example 3]
Alq3 and Compound No. 2-1 were co-deposited to a total thickness of about 44 nm at a deposition rate of 0.1 to 0.2 nm / sec and 0.003 to 0.007 nm / sec (3.11 wt%), respectively. Then, an EL device was obtained in the same manner as in Example 1 except that Alq3 was deposited at a deposition rate of 0.1 to 0.2 nm / sec to a thickness of about 7 nm to form an electron injecting and transporting layer.

When a DC voltage of 11 V was applied to the EL element, a current flowed about 62 mA / cm ² , and a light emission luminance of 150 cd / m ² and a light emission efficiency of 0.71 m / W were obtained. The emission color was red, the peak wavelengths were 630 nm and 685 nm, and the CIE chromaticity coordinates were x = 0.68 and y = 0.31. The device was continuously driven at a constant current density of 10 mA / cm ^{2 in} a dry atmosphere. Initially, it was 24 cd / m ² at 6.2 V, the luminance half-life was about 150 hours, and the drive voltage increase during that period was 1.6 V.

[Example 4]
An EL device was obtained in the same manner as in Example 3 except that Compound No. 2-1 was replaced with 6,13-bis (m-tolyl) pentacene (Compound No. 2-4). As a result, red light emission having characteristics equivalent to those of Example 3 was obtained.

[Example 5]
A glass substrate having an ITO transparent electrode (anode) having a thickness of 200 nm was subjected to ultrasonic cleaning using a neutral detergent, acetone, and ethanol. The substrate was lifted from boiling ethanol, dried, washed with UV / O ₃ , fixed to a substrate holder of a vacuum deposition apparatus, and the vacuum chamber was depressurized to 1 × 10 ⁻⁴ Pa or less.

  First, poly (thiophene-2,5-diyl) was deposited to a thickness of about 10 nm at a deposition rate of about 0.1 nm / sec to form a hole injection layer. Next, TPD was deposited to a thickness of about 45 nm at a deposition rate of 0.1 to 0.2 nm / sec to form a hole transport layer.

  Next, while maintaining the reduced pressure state, TPD as the hole injecting and transporting compound and Alq3 as the electron injecting and transporting compound were mixed at the same deposition rate (0.1 to 0.2 nm / sec) and at the same time, compound No. 2 -1 was also deposited at a deposition rate of 0.006 to 0.014 nm / sec (3.25 wt%) to form a mixed layer as a light emitting layer with a thickness of about 40 nm.

  Further, while maintaining the reduced pressure state, Alq3 was deposited at a deposition rate of 0.1 to 0.2 nm / sec to a thickness of about 30 nm to form an electron injecting and transporting layer.

  Furthermore, while maintaining the reduced pressure state, Mg and Ag are deposited to a total thickness of about 200 nm at a deposition rate of 0.1 to 0.2 nm / sec and 0.02 to 0.04 nm / sec (weight ratio 10: 1), respectively. Co-evaporation was used as a cathode to obtain an EL element.

When a DC voltage of 10 V was applied to this EL element, a current flowed about 100 mA / cm ² , and an emission luminance of 360 cd / m ² and an emission efficiency of 1.11 m / W were obtained. The emission color was red, the peak wavelengths were 630 nm and 685 nm, and the CIE chromaticity coordinates were x = 0.69 and y = 0.30. The device was continuously driven at a constant current density of 10 mA / cm ^{2 in} a dry atmosphere. Initially, it was 37 cd / m ² at 6.9 V, the luminance half-life was about 1200 hours, and the drive voltage increase during that period was 4.6 V.

[Example 6]
An EL device was obtained in the same manner as in Example 3 except that Compound No. 2-1 was replaced by Compound No. 4-1. In this EL element, green light emission having a peak wavelength of 530 to 540 nm was obtained.

  In Examples 1 to 3 and 5, one or more of the compounds represented by the general formula (I) are used in place of Compound No. 2-1, and Examples 1 to 6 are combinations of compounds. When various EL devices having different values were obtained and the characteristics were examined in the same manner, similar results were obtained according to the device configuration and the like.

It is a side view which shows the structural example of the organic EL element of this invention. It is a graph which shows the infrared absorption spectrum of the compound synthesize | combined by this invention. It is a graph which shows the NMR spectrum of the compound synthesize | combined by this invention. It is a graph which shows the infrared absorption spectrum of the compound synthesize | combined by this invention. It is a graph which shows the NMR spectrum of the compound synthesize | combined by this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Organic EL element 2 Substrate 3 Anode 4 Hole injection transport layer 5 Light emitting layer 6 Electron injection transport layer 7 Cathode

Claims (10)

An organic EL device having at least one organic compound layer containing a compound represented by the following general formula (I).
Formula (I)
(Ar) m-L
(In the general formula (I), Ar is an alkylphenyl group or an arylphenyl group, m is 2, and L is a divalent residue derived from pentacene. ) The organic EL device according to claim 1, wherein the organic compound layer containing the compound represented by the general formula (I) is a light emitting layer. The organic EL device according to claim 2 , wherein the light emitting layer contains a quinoline derivative. The organic EL device according to claim 3 , wherein the quinoline derivative is tris (8-quinolinolato) aluminum. The light-emitting layer is at least one more hole injecting and transporting compound and an organic EL element according to any one of claims 2 to 4 is a mixed layer of at least one or more electron injecting and transporting compound. In the compound represented by said light emitting layer by the general formula (I), an organic EL device according to any one of claims 2 to 5 is contained in a concentration of 0.01 wt% 20 wt%. The organic EL device according to any one of claims 2 to 6 having a positive hole injection transport layer of at least one layer. The organic EL device according to claim 7 , wherein the hole injection / transport layer includes at least one hole injection layer and at least one hole transport layer, and the light emitting layer is in contact with the hole transport layer. The organic EL device according to any one of claims 2 to 8 having an electron injection transport layer of at least one layer. The organic EL device according to claim 9 , wherein the electron injection / transport layer includes at least one electron injection layer and at least one electron transport layer, and the light emitting layer is in contact with the electron transport layer.

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