JP2012094823A - Pyridylphenyl-substituted anthracene compound and organic electroluminescent element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an organic electroluminescent element which is excellent in lifetime and driving voltage.SOLUTION: An organic electroluminescent element is manufactured using an anthracene compound having a pyridylphenyl group as an electron transport material. The electron transport material is especially suitable for a blue light-emitting element, and thus allows manufacturing of a blue light-emitting element having an element lifetime equal to those of red and green light-emitting elements. Also, a display device having high-performance such as full-color display or the like can be obtained by using the organic electroluminescent element.

Description

  The present invention relates to pyridylphenyl substituted anthracene compounds, more particularly 9,10-bis (4- (pyridin-4-yl) phenylanthracene compounds or 9,10-bis (3- (pyridin-4-yl) phenylanthracene. The present invention relates to a compound, and an organic electroluminescent element, a display device, and a lighting device using the compound.

  2. Description of the Related Art Conventionally, display devices using light emitting elements that emit electroluminescence have been studied variously because they can be reduced in power and thinned. Further, organic electroluminescent elements made of organic materials can be easily reduced in weight and size. Therefore, it has been actively studied. In particular, the development of organic materials with light emission characteristics such as blue, which is one of the three primary colors of light, and organic materials that have charge transporting ability (such as semiconductors and superconductors) such as holes and electrons The development of materials has been actively studied so far, regardless of whether it is a high molecular compound or a low molecular compound.

  For example, a method for synthesizing a compound having a pyridylphenyl structure in the molecule and an organic electroluminescent device using the compound in an organic compound layer have been reported (Japanese Patent Laid-Open No. 2003-282270 (Patent Document 1)). Patent Document 1 reports an organic electroluminescent device using a compound having a pyridylphenyl structure in the molecule as an electron transport material. An organic electroluminescence device using a compound in which a pyridylphenyl group is substituted on the central skeleton of anthracene has also been reported (Japanese Patent Laid-Open No. 2009-173642 (Patent Document 2)).

JP 2003-282270 A JP 2009-173642 A

  As described above, several electron transport materials of compounds having a pyridylphenyl structure in the molecule are known, but these known materials are generally used for electron transport materials (materials for electron transport layers and electron injection layers). From the viewpoint of prolonging the life of the light-emitting element, which is required in particular, it has not had sufficient characteristics. Under such circumstances, development of an electron transport material that can improve the element lifetime of the light emitting element is desired. In particular, for blue light-emitting elements, an electron transport material having superior characteristics compared to red and green light-emitting elements has not been obtained, and development of an electron transport material suitable for extending the life of blue light-emitting elements is desired. It is rare.

  As a result of intensive studies to solve the above-mentioned problems, the inventors of the present invention have made the organic electroluminescence device provided with an organic layer containing a compound represented by the following general formula (1) as an electron transport material. The inventors have found that an organic electroluminescent device having excellent device life characteristics can be obtained, and have completed the present invention.

式（１）中、Ａｒは炭素数１０〜２４のアリールであり、当該アリールは、炭素数１〜１２のアルキル、炭素数３〜１２のシクロアルキルまたは炭素数６〜２０のアリールで置換されていてもよく、４−ピリジル基は共にフェニルの３位または４位に連結し、また、式（１）で表される化合物における少なくとも１つの水素が重水素で置換されていてもよい。 [1] An electron transport material containing a compound represented by the following general formula (1).

In the formula (1), Ar is aryl having 10 to 24 carbon atoms, and the aryl is substituted with alkyl having 1 to 12 carbons, cycloalkyl having 3 to 12 carbons, or aryl having 6 to 20 carbons. The 4-pyridyl group may be linked to the 3- or 4-position of phenyl, and at least one hydrogen in the compound represented by the formula (1) may be substituted with deuterium.

式（１−１）中、Ａｒは炭素数１０〜２４のアリールであり、当該アリールは、炭素数１〜１２のアルキル、炭素数３〜１２のシクロアルキルまたは炭素数６〜２０のアリールで置換されていてもよく、また、式（１−１）で表される化合物における少なくとも１つの水素が重水素で置換されていてもよい。 [2] An electron transport material containing a compound represented by the following general formula (1-1).

In Formula (1-1), Ar is aryl having 10 to 24 carbon atoms, and the aryl is substituted with alkyl having 1 to 12 carbons, cycloalkyl having 3 to 12 carbons, or aryl having 6 to 20 carbons. In addition, at least one hydrogen in the compound represented by the formula (1-1) may be substituted with deuterium.

式（１−２）中、Ａｒは炭素数１０〜２４のアリールであり、当該アリールは、炭素数１〜１２のアルキル、炭素数３〜１２のシクロアルキルまたは炭素数６〜２０のアリールで置換されていてもよく、また、式（１−２）で表される化合物における少なくとも１つの水素が重水素で置換されていてもよい。 [3] An electron transport material containing a compound represented by the following general formula (1-2).

In Formula (1-2), Ar is aryl having 10 to 24 carbon atoms, and the aryl is substituted with alkyl having 1 to 12 carbons, cycloalkyl having 3 to 12 carbons, or aryl having 6 to 20 carbons. In addition, at least one hydrogen in the compound represented by the formula (1-2) may be substituted with deuterium.

[4] The electron transport material according to any one of [1] to [3], wherein Ar is biphenylyl, terphenylyl, or naphthyl, and the naphthyl may be substituted with phenyl.

[5] The electron transport according to any one of [1] to [3], wherein Ar is 3-biphenylyl, 4-biphenylyl, m-terphenyl-5′-yl, 1-naphthyl, or 2-naphthyl. material.

[6] A pair of electrodes composed of an anode and a cathode, a light emitting layer disposed between the pair of electrodes, and disposed between the cathode and the light emitting layer, and any one of [1] to [5] An organic electroluminescent device having an electron transport layer and / or an electron injection layer containing the electron transport material described in 1.

[7] At least one of the electron transport layer and the electron injection layer further contains at least one selected from the group consisting of a quinolinol-based metal complex, a bipyridine derivative, a phenanthroline derivative, a borane derivative, and a benzimidazole derivative. Organic electroluminescent element as described in said [6].

[8] At least one of the electron transport layer and the electron injection layer further includes an alkali metal, an alkaline earth metal, a rare earth metal, an alkali metal oxide, an alkali metal halide, an alkaline earth metal oxide, At least one selected from the group consisting of alkaline earth metal halides, rare earth metal oxides, rare earth metal halides, alkali metal organic complexes, alkaline earth metal organic complexes and rare earth metal organic complexes The organic electroluminescent element as described in [6] or [7] above.

[9] A display device comprising the organic electroluminescent element according to any one of [6] to [8].

[10] An illumination device including the organic electroluminescent element according to any one of [6] to [8].

  According to a preferred embodiment of the present invention, an organic electroluminescent element having a particularly long driving life can be obtained. Further, the preferred electron transport material of the present invention is particularly suitable for a blue light emitting element, and according to this electron transport material, a blue light emitting element having an element life comparable to a red or green light emitting element can be produced. Can do. Furthermore, by using this organic electroluminescent element, a high-performance display device such as a full-color display can be obtained.

It is a schematic sectional drawing which shows the organic electroluminescent element which concerns on this embodiment.

1. Compounds represented by general formula (1), formula (1-1), and formula (1-2) Hereinafter, 9,10-bis (4- (pyridine-4-) represented by general formula (1-1) Yl) phenylanthracene compound and the 9,10-bis (3- (pyridin-4-yl) phenylanthracene compound represented by the general formula (1-2) will be described in detail. The structure of the present invention is a superordinate formula combining the structures of the formula (1-1) and the formula (1-2) .The compound of the present invention is particularly “4- (pyridin-4-yl)” among the pyridylphenyl groups. The “phenyl group” or “3- (pyridin-4-yl) phenyl group” is substituted at the 9th and 10th positions of the anthracene structure, and among the aryl groups, the “aryl group that is more bulky than the phenyl group” is particularly Compound substituted at the 2-position There, by selecting such substituents, the compounds that have achieved excellent device lifetime by the case of using an organic EL element.

  Ar in Formula (1-1) or Formula (1-2) is aryl having 10 to 24 carbon atoms, and the aryl is alkyl having 1 to 12 carbons, cycloalkyl having 3 to 12 carbons, or carbon. It may be substituted with an aryl of 6 to 20, and at least one hydrogen in the compound represented by formula (1-1) or formula (1-2) may be substituted with deuterium.

  As for “aryl having 10 to 24 carbon atoms” which is Ar, aryl having 12 to 24 carbon atoms is preferable, and aryl having 18 to 24 carbon atoms is particularly preferable.

  Specific examples of “aryl having 10 to 24 carbon atoms” include (2-, 3-, 4-) biphenylyl which is bicyclic aryl, (1-, 2-) naphthyl which is condensed bicyclic aryl, three Ring system aryl terphenylyl (m-terphenyl-2'-yl, m-terphenyl-4'-yl, m-terphenyl-5'-yl, o-terphenyl-3'-yl, o-tel Phenyl-4′-yl, p-terphenyl-2′-yl, m-terphenyl-2-yl, m-terphenyl-3-yl, m-terphenyl-4-yl, o-terphenyl-2 -Yl, o-terphenyl-3-yl, o-terphenyl-4-yl, p-terphenyl-2-yl, p-terphenyl-3-yl, p-terphenyl-4-yl), condensation Anthracene- (1- 2-, 9-) yl, acenaphthylene- (1-, 3-, 4-, 5-) yl, fluorene- (1-, 2-, 3-, 4-, 9-) yl, phenalene- (1- , 2-) yl, (1-, 2-, 3-, 4-, 9-) phenanthryl, condensed tetracyclic aryl triphenylene- (1-, 2-) yl, pyrene- (1-, 2- , 4-) yl, tetracene- (1-, 2-, 5-) yl, condensed pentacyclic aryl, perylene- (1-, 2-, 3-) yl, and the like.

  Preferred “aryl having 10 to 24 carbon atoms” is biphenylyl, terphenylyl or naphthyl, more preferably m-terphenyl-5′-yl or 1-naphthyl.

  “Alkyl having 1 to 12 carbon atoms” as a substituent for Ar may be either a straight chain or a branched chain. That is, it is a linear alkyl having 1 to 12 carbons or a branched alkyl having 3 to 12 carbons. More preferably, it is C1-C6 alkyl (C3-C6 branched alkyl), More preferably, it is C1-C4 alkyl (C3-C4 branched alkyl). is there. Specific examples include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, s-butyl, t-butyl, n-pentyl, isopentyl, neopentyl, t-pentyl, n-hexyl, 1-methylpentyl, 4-methyl-2-pentyl, 3,3-dimethylbutyl, 2-ethylbutyl and the like are listed, and methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, s-butyl, or t-butyl is preferable. More preferred are methyl, ethyl, or t-butyl.

  Specific examples of “cycloalkyl having 3 to 12 carbon atoms” which is a substituent of Ar include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, methylcyclopentyl, cycloheptyl, methylcyclohexyl, cyclooctyl, and dimethylcyclohexyl.

  As the “aryl having 6 to 20 carbon atoms” which is a substituent of Ar, aryl having 6 to 12 carbon atoms is preferable, and aryl having 6 to 10 carbon atoms is particularly preferable. Specific examples include those described in the above specific examples of “aryl having 10 to 24 carbon atoms” in addition to the phenyl group, preferably phenyl, (2-, 3-, 4-) biphenylyl, (1 -, 2-) naphthyl and the like, particularly preferably phenyl.

  When Ar has a substituent, the number of substituents is, for example, the maximum number of substituents, preferably 1 to 3, more preferably 1 to 2, and still more preferably 1.

Specific examples of Ar (structure including a substituent) include the following groups.

  Further, all or part of the hydrogen atoms in the anthracene skeleton, the hydrogen atoms in the pyridylphenyl group, and the hydrogen atoms in Ar constituting the compounds represented by the general formulas (1-1) and (1-2) are deuterium. There may be. When the compound is deuterated, it is preferable that the hydrogen atom in the pyridylphenyl group or the hydrogen atom in Ar is deuterated.

  Specific examples of the compound represented by the general formula (1-1) include compounds represented by the following formula (1-1-1) to formula (1-1-12). Among the following compounds, compounds represented by the following formula (1-1-2) to formula (1-1-4), formula (1-1-7) and formula (1-1-10) are preferable.

  Specific examples of the compound represented by the general formula (1-2) include compounds represented by the following formulas (1-2-1) to (1-2-12). Among the following compounds, the following formula (1-2-1), formula (1-2-2), formula (1-2-4), formula (1-2-7), and formula (1-2-10) The compound represented by these is preferable.

2. Process for Producing Compounds Represented by General Formulas (1-1) and (1-2) Next, the process for producing the compound of the present invention will be described. The compound of the present invention basically comprises a known compound and a known synthesis method such as Suzuki coupling reaction or Negishi coupling reaction (for example, “Metal-Catalyzed Cross-Coupling Reactions-Second, Completely Revised and It can be synthesized using “Enlarged Edition”. It can also be synthesized by combining both reactions. A scheme for synthesizing the compounds represented by the general formulas (1-1) and (1-2) by Suzuki coupling reaction or Negishi coupling reaction is illustrated below.

  When producing the compound of the present invention, (1) a method of synthesizing a group in which pyridyl (terminal group) and phenyl (intermediate group) are bonded, and bonding this to the 9,10 position of anthracene, (2 ) A method in which a phenyl group is bonded to the 9th and 10th positions of anthracene, and a pyridyl group is bonded to this phenyl group. In addition, the bond between the phenyl group and the pyridyl group and the bond between the anthracene and the phenyl group in these methods basically include a halogen functional group or a trifluoromethanesulfonate functional group, a zinc chloride complex, or a boronic acid (boron). A coupling reaction with an acid ester) can be used.

  First, (1) a method of synthesizing a group in which pyridyl (terminal group) and phenyl (intermediate group) are bonded and bonding them to the 9th and 10th positions of anthracene will be described. Note that (2) a method of bonding a phenyl group to the 9th and 10th positions of anthracene and bonding a pyridyl group to this phenyl group, referring to various coupling reactions described in the method of (1), A phenyl group may be bonded to the 9th and 10th positions of anthracene, and a pyridyl group may be bonded to this phenyl group.

<Method for Synthesizing Compounds Represented by General Formulas (1-1) and (1-2) (Part 1)>
<Synthesis of 4- (4-bromophenyl) pyridine or 4- (3-bromophenyl) pyridine>
First, a zinc chloride complex of pyridine is synthesized by the following reaction formula (1), and then a zinc chloride complex of pyridine is reacted with 1,4-dibromobenzene or 1,3-dibromobenzene by the following reaction formula (2). Can synthesize 4- (4-bromophenyl) pyridine or 4- (3-bromophenyl) pyridine. In the reaction formula (1), “ZnCl ₂ · TMEDA” is a tetramethylethylenediamine complex of zinc chloride. Here, a synthesis method using 4-bromopyridine as a raw material is exemplified, but 4- (4-bromophenyl) pyridine or 4- (3-bromophenyl) pyridine can also be obtained by using 4-iodopyridine as a raw material. Can be synthesized. Further, although 1,4-dibromobenzene or 1,3-dibromobenzene was used as a raw material here, it can also be synthesized by using 1-bromo-4-iodobenzene or 1-bromo-3-iodobenzene. In addition, instead of reacting 1,4-dibromobenzene or 1,3-dibromobenzene with a zinc chloride complex of pyridine, it can also be obtained by a coupling reaction in which 4-pyridineboronic acid or 4-pyridineboronic acid ester is reacted. Can do.

  In the above reaction formula (1), R represents a linear or branched alkyl group, preferably a linear or branched alkyl group having 1 to 4 carbon atoms.

<Synthesis of anthracene-9,10-diboronic acid (or boronic ester) substituted at position 2 with Ar>
First, as shown in the following reaction formula (3), 2- (naphthalen-2-yl) -9,10-dibromo is obtained by brominating anthracene substituted at the 2-position using an appropriate brominating agent. Anthracene is obtained. Suitable brominating agents include bromine or N-brominated succinimide (NBS). Here, anthracene substituted at the 2-position with a 2-naphthyl group is exemplified, but 9,10-dibromoanthracene into which various Ars are introduced can be obtained by appropriately changing the raw materials.

  Anthracene having a substituent at the 2-position (2-naphthyl group in the above reaction formula (3)) is anthracene substituted at the 2-position with halogen or triflate and a boronic acid (or boron) of a group corresponding to the substituent. Anthracene having a substituent at the 2-position can be synthesized by Suzuki coupling with (acid ester). Another method is a synthesis method by Negishi coupling between anthracene substituted at the 2-position with halogen or triflate and a zinc complex of a group corresponding to the substituent. Further, a synthesis method by Suzuki coupling of 2-anthraceneboronic acid (or boronate ester) and a group corresponding to the substituent substituted with halogen or triflate, and further, with 2-anthracene zinc complex and halogen or triflate A synthesis method by Negishi coupling with a group corresponding to the substituted group is also included.

  Next, as shown in the following reaction formula (4), 2- (naphthalen-2-yl) -9,10-dibromoanthracene is lithiated using an organic lithium reagent, or magnesium or an organic magnesium reagent is used. Thus, 2- (naphthalen-2-yl) anthracene-9,10-diboronic acid ester can be synthesized by reacting with trimethyl borate, triethyl borate or triisopropyl borate as a Grignard reagent. Further, this 2- (naphthalen-2-yl) anthracene-9,10-diboronic acid ester is hydrolyzed by the following reaction formula (5) to give 2- (naphthalen-2-yl) anthracene-9,10- Diboronic acid can be synthesized.

  In the above reaction formula (4), R represents a linear or branched alkyl group, preferably a linear or branched alkyl group having 1 to 4 carbon atoms.

  Further, as shown in the following reaction formula (6), 2- (naphthalen-2-yl) -9,10-dibromoanthracene is lithiated using an organic lithium reagent, or using magnesium or an organic magnesium reagent. By reacting with bis (pinacolato) diboron or 4,4,5,5-tetramethyl-1,3,2-dioxaborolane as a Grignard reagent, other 2- (naphthalen-2-yl) anthracene-9,10 -Diboronic acid esters can be synthesized. Further, as shown in the following reaction formula (7), 2- (naphthalen-2-yl) -9,10-dibromoanthracene and bis (pinacolato) diboron or 4,4,5,5-tetramethyl-1,3 , 2-Dioxaborolane can be synthesized using a palladium catalyst and a base to produce a similar 2- (naphthalen-2-yl) anthracene-9,10-diboronic acid ester.

  In the above reaction formula (6), R represents a linear or branched alkyl group, preferably a linear or branched alkyl group having 1 to 4 carbon atoms.

  In the reaction formula (4), (6) or (7), chloride, iodide or triflate is used instead of bromide such as 2- (naphthalen-2-yl) -9,10-dibromoanthracene. Even if it uses, it can synthesize | combine similarly.

<Synthesis of the compound according to the present invention by Suzuki coupling reaction>
Finally, as shown in the following reaction formula (8), 2- (naphthalen-2-yl) anthracene-9,10-diboronic acid or 2- (naphthalen-2-yl) anthracene synthesized as described above. The present invention is made by reacting -9,10-diboronic acid esters with 2-fold moles of 4- (4-bromophenyl) pyridine or 4- (3-bromophenyl) pyridine in the presence of a palladium catalyst and a base. The compound which concerns on can be synthesize | combined.

  Further, as shown in the following reaction formula (9), 2- (naphthalen-2-yl) -9,10-dibromoanthracene is added to a 2-fold mole of boronic acid or boronic acid ester of pyridylbenzene with a palladium catalyst and a base. By reacting in the presence of, the compound according to the present invention can be synthesized. The boronic acid or boronic acid ester of pyridylbenzene was synthesized from 4- (4-bromophenyl) pyridine or 4- (3-bromophenyl) pyridine by a method according to the above reaction formulas (4) to (7). can do.

Specific examples of the palladium catalyst used in the Suzuki coupling reaction include tetrakis (triphenylphosphine) palladium (0): Pd (PPh ₃ ) ₄ , bis (triphenylphosphine) palladium (II) dichloride: PdCl ₂ (PPh ₃ ) ₂ , palladium (II) acetate: Pd (OAc) ₂ , tris (dibenzylideneacetone) dipalladium (0): Pd ₂ (dba) ₃ , tris (dibenzylideneacetone) dipalladium (0) chloroform complex: Pd ₂ (Dba) ₃ · CHCl ₃ , or bis (dibenzylideneacetone) palladium (0): Pd (dba) ₂ .

  In order to accelerate the reaction, a phosphine compound may be added to these palladium compounds in some cases. Specific examples of the phosphine compound include tri (t-butyl) phosphine, tricyclohexylphosphine, 1- (N, N-dimethylaminomethyl) -2- (di-t-butylphosphino) ferrocene, 1- (N, N-dibutylaminomethyl) -2- (di-t-butylphosphino) ferrocene, 1- (methoxymethyl) -2- (di-t-butylphosphino) ferrocene, 1,1′-bis (di-t-butylphos Fino) ferrocene, 2,2′-bis (di-t-butylphosphino) -1,1′-binaphthyl, 2-methoxy-2 ′-(di-t-butylphosphino) -1,1′-binaphthyl, or An example is 2-dicyclohexylphosphino-2 ′, 6′-dimethoxybiphenyl.

  Specific examples of the base used in the reaction include sodium carbonate, potassium carbonate, cesium carbonate, sodium bicarbonate, sodium hydroxide, potassium hydroxide, barium hydroxide, sodium ethoxide, sodium t-butoxide, sodium acetate, phosphoric acid. Examples include tripotassium or potassium fluoride.

  Specific examples of the solvent used in the reaction include benzene, toluene, xylene, 1,2,4-trimethylbenzene, N, N-dimethylformamide, tetrahydrofuran, diethyl ether, t-butyl methyl ether, 1,4- Examples include dioxane, methanol, ethanol, cyclopentyl methyl ether, and isopropyl alcohol. These solvents can be appropriately selected and may be used alone or as a mixed solvent.

<Method for Synthesizing Compounds Represented by General Formulas (1-1) and (1-2) (Part 2)>
<Synthesis of anthracene-9,10-dizinc complex substituted at position 2 with Ar>
First, as shown in the following reaction formula (10), 2- (naphthalen-2-yl) -9,10-dibromoanthracene is lithiated using an organic lithium reagent, or using magnesium or an organic magnesium reagent. A 2- (naphthalen-2-yl) anthracene-9,10-dizinc complex can be synthesized by reacting with zinc chloride or zinc chloride tetramethylethylenediamine complex (ZnCl ₂ · TMEDA) as a Grignard reagent.

  In the above reaction formula (10), R represents a linear or branched alkyl group, preferably a linear or branched alkyl group having 1 to 4 carbon atoms. In addition, it can synthesize | combine similarly even if it uses a chloride or iodide instead of bromide like 2- (naphthalen-2-yl) -9,10-dibromoanthracene. The method for introducing another substituent (Ar) at the 2-position of anthracene is as described in the above-mentioned column of the Suzuki coupling reaction.

<Synthesis of the compound according to the present invention by Negishi coupling reaction>
Finally, as shown in the following reaction formula (11), 2- (naphthalen-2-yl) anthracene-9,10-dizinc complex synthesized as described above was added to 2-fold mole of 4- (4 The compound according to the present invention can be synthesized by reacting -bromophenyl) pyridine or 4- (3-bromophenyl) pyridine in the presence of a palladium catalyst.

  In addition, as shown in the following reaction formula (12), 2- (naphthalen-2-yl) -9,10-dibromoanthracene, 4- (4-bromophenyl) pyridine or 4- (3-bromophenyl) pyridine The compound according to the present invention can be synthesized by reacting 2-fold mol of 4-pyridylbenzenezinc complex synthesized by a method according to the above reaction formula (10) in the presence of a palladium catalyst.

Specific examples of the palladium catalyst used in the Negishi coupling reaction include tetrakis (triphenylphosphine) palladium (0): Pd (PPh ₃ ) ₄ , bis (triphenylphosphine) palladium (II) dichloride: PdCl ₂ (PPh ₃ ) ₂ , palladium (II) acetate: Pd (OAc) ₂ , tris (dibenzylideneacetone) dipalladium (0): Pd ₂ (dba) ₃ , tris (dibenzylideneacetone) dipalladium (0) chloroform complex: Pd ₂ (Dba) ₃ · CHCl ₃ , bis (dibenzylideneacetone) palladium (0): Pd (dba) ₂ , bis (tri-t-butylphosphino) palladium (0), or (1,1′-bis (diphenylphosphine) Fino) ferrocene) dichloropalladium (II).

  Specific examples of the solvent used in the reaction include benzene, toluene, xylene, 1,2,4-trimethylbenzene, N, N-dimethylformamide, tetrahydrofuran, diethyl ether, t-butyl methyl ether, cyclopentyl methyl ether or 1,4-dioxane. These solvents can be appropriately selected and may be used alone or as a mixed solvent.

  In addition, the compounds of the present invention include those in which at least a part of the hydrogen atoms are substituted with deuterium. Such a compound can be obtained by using a raw material in which a desired position is deuterated. It can be synthesized in the same way.

3. Organic Electroluminescent Device The anthracene compound having a pyridylphenyl group according to the present invention can be used as a material for an organic electroluminescent device, for example. Below, the organic electroluminescent element which concerns on this embodiment is demonstrated in detail based on drawing. FIG. 1 is a schematic cross-sectional view showing an organic electroluminescent element according to this embodiment.

<Structure of organic electroluminescence device>
An organic electroluminescent device 100 shown in FIG. 1 includes a substrate 101, an anode 102 provided on the substrate 101, a hole injection layer 103 provided on the anode 102, and a hole injection layer 103. A hole transport layer 104 provided on the light emitting layer 105, a light emitting layer 105 provided on the hole transport layer 104, an electron transport layer 106 provided on the light emitting layer 105, and an electron transport layer 106. And the cathode 108 provided on the electron injection layer 107.

  The organic electroluminescent element 100 is manufactured in the reverse order, for example, the substrate 101, the cathode 108 provided on the substrate 101, the electron injection layer 107 provided on the cathode 108, and the electron injection layer. An electron transport layer 106 provided on 107, a light-emitting layer 105 provided on the electron transport layer 106, a hole transport layer 104 provided on the light-emitting layer 105, and a hole transport layer 104 A structure including the hole injection layer 103 provided above and the anode 102 provided on the hole injection layer 103 may be employed.

  Not all of the above-described layers are necessary, and the minimum structural unit is composed of the anode 102, the light emitting layer 105, the electron transport layer 106 and / or the electron injection layer 107 and the cathode 108. The hole transport layer 104 is an arbitrarily provided layer. Moreover, each said layer may consist of a single layer, respectively, and may consist of multiple layers.

  As an aspect of the layer constituting the organic electroluminescence device, in addition to the above-described configuration aspect of “substrate / anode / hole injection layer / hole transport layer / light emitting layer / electron transport layer / electron injection layer / cathode”, "Substrate / anode / hole transport layer / light emitting layer / electron transport layer / electron injection layer / cathode", "substrate / anode / hole injection layer / light emitting layer / electron transport layer / electron injection layer / cathode", "substrate / Anode / hole injection layer / hole transport layer / light emitting layer / electron injection layer / cathode ”,“ substrate / anode / hole injection layer / hole transport layer / light emitting layer / electron transport layer / cathode ”,“ substrate ” / Anode / light emitting layer / electron transport layer / electron injection layer / cathode ”,“ substrate / anode / hole transport layer / light emitting layer / electron injection layer / cathode ”,“ substrate / anode / hole transport layer / light emitting layer / “Electron transport layer / cathode”, “substrate / anode / hole injection layer / light emitting layer / electron injection layer / cathode”, “substrate / anode / hole injection layer / light emitting layer / electron transport” Layer / cathode "," substrate / anode / light emitting layer / electron transporting layer / cathode "may be configured aspect of the" substrate / anode / light emitting layer / electron injection layer / cathode ".

<Substrate in organic electroluminescence device>
The substrate 101 serves as a support for the organic electroluminescent device 100, and usually quartz, glass, metal, plastic, or the like is used. The substrate 101 is formed into a plate shape, a film shape, or a sheet shape according to the purpose. For example, a glass plate, a metal plate, a metal foil, a plastic film, a plastic sheet, or the like is used. Of these, glass plates and transparent synthetic resin plates such as polyester, polymethacrylate, polycarbonate, polysulfone and the like are preferable. In the case of a glass substrate, soda lime glass, non-alkali glass, or the like is used, and the thickness only needs to be sufficient to maintain the mechanical strength. The upper limit value of the thickness is, for example, 2 mm or less, preferably 1 mm or less. The glass material is preferably alkali-free glass because it is better to have less ions eluted from the glass. However, soda lime glass with a barrier coat such as SiO ₂ is also commercially available, so it can be used. it can. Further, the substrate 101 may be provided with a gas barrier film such as a dense silicon oxide film on at least one surface in order to improve the gas barrier property, and a synthetic resin plate, film or sheet having a low gas barrier property is used as the substrate 101. When used, it is preferable to provide a gas barrier film.

<Anode in organic electroluminescence device>
The anode 102 serves to inject holes into the light emitting layer 105. When the hole injection layer 103 and / or the hole transport layer 104 are provided between the anode 102 and the light emitting layer 105, holes are injected into the light emitting layer 105 through these layers. .

  Examples of the material for forming the anode 102 include inorganic compounds and organic compounds. Examples of inorganic compounds include metals (aluminum, gold, silver, nickel, palladium, chromium, etc.), metal oxides (indium oxide, tin oxide, indium-tin oxide (ITO), indium-zinc oxide). Products (IZO), metal halides (copper iodide, etc.), copper sulfide, carbon black, ITO glass, Nesa glass, and the like. Examples of the organic compound include polythiophene such as poly (3-methylthiophene), conductive polymer such as polypyrrole and polyaniline, and the like. In addition, it can select suitably from the substances currently used as an anode of an organic electroluminescent element, and can use it.

  The resistance of the transparent electrode is not limited as long as it can supply a sufficient current for light emission of the light emitting element, but is preferably low resistance from the viewpoint of power consumption of the light emitting element. For example, an ITO substrate of 300Ω / □ or less functions as an element electrode. However, since it is now possible to supply a substrate of about 10Ω / □, for example, 100-5Ω / □, preferably 50-5Ω. It is particularly desirable to use a low resistance product of / □. The thickness of ITO can be arbitrarily selected according to the resistance value, but is usually used in a range of 100 to 300 nm.

<Hole injection layer and hole transport layer in organic electroluminescence device>
The hole injection layer 103 plays a role of efficiently injecting holes moving from the anode 102 into the light emitting layer 105 or the hole transport layer 104. The hole transport layer 104 plays a role of efficiently transporting holes injected from the anode 102 or holes injected from the anode 102 through the hole injection layer 103 to the light emitting layer 105. The hole injection layer 103 and the hole transport layer 104 are each formed by laminating and mixing one kind or two or more kinds of hole injection / transport materials or a mixture of the hole injection / transport material and the polymer binder. Is done. In addition, an inorganic salt such as iron (III) chloride may be added to the hole injection / transport material to form a layer.

  As a hole injection / transport material, it is necessary to efficiently inject and transport holes from the positive electrode between electrodes to which an electric field is applied. The hole injection efficiency is high, and the injected holes are transported efficiently. It is desirable to do. For this purpose, it is preferable to use a substance that has a low ionization potential, a high hole mobility, excellent stability, and is less likely to generate trapping impurities during production and use.

  As a material for forming the hole injection layer 103 and the hole transport layer 104, in a photoconductive material, a compound conventionally used as a charge transport material for holes, a p-type semiconductor, and a hole injection of an organic electroluminescent element are used. Any known material used for the layer and the hole transport layer can be selected and used. Specific examples thereof include carbazole derivatives (N-phenylcarbazole, polyvinylcarbazole, etc.), biscarbazole derivatives such as bis (N-arylcarbazole) or bis (N-alkylcarbazole), triarylamine derivatives (aromatic tertiary class). Polymer having amino group in main chain or side chain, 1,1-bis (4-di-p-tolylaminophenyl) cyclohexane, N, N′-diphenyl-N, N′-di (3-methylphenyl)- 4,4′-diaminobiphenyl, N, N′-diphenyl-N, N′-dinaphthyl-4,4′-diaminobiphenyl, N, N′-diphenyl-N, N′-di (3-methylphenyl)- 4,4′-diphenyl-1,1′-diamine, N, N′-dinaphthyl-N, N′-diphenyl-4,4′-diphenyl- , 1′-diamine, 4,4 ′, 4 ″ -tris (3-methylphenyl (phenyl) amino) triphenylamine, and the like, starburstamine derivatives, and the like, stilbene derivatives, phthalocyanine derivatives (metal-free, Copper phthalocyanine), pyrazoline derivatives, hydrazone compounds, benzofuran derivatives, thiophene derivatives, heterocyclic compounds such as oxadiazole derivatives, porphyrin derivatives, polysilanes, etc. Styrene derivatives, polyvinyl carbazole, polysilane, and the like are preferable, but there is no particular limitation as long as it is a compound that forms a thin film necessary for manufacturing a light-emitting element, can inject holes from the anode, and can further transport holes. .

  It is also known that the conductivity of organic semiconductors is strongly influenced by the doping. Such an organic semiconductor matrix material is composed of a compound having a good electron donating property or a compound having a good electron accepting property. Strong electron acceptors such as tetracyanoquinone dimethane (TCNQ) or 2,3,5,6-tetrafluorotetracyano-1,4-benzoquinone dimethane (F4TCNQ) are known for doping of electron donor materials. (For example, the document “M. Pfeiffer, A. Beyer, T. Fritz, K. Leo, Appl. Phys. Lett., 73 (22), 3202-3204 (1998)”) and the document “J. Blochwitz, M Pheiffer, T. Fritz, K. Leo, Appl. Phys. Lett., 73 (6), 729-731 (1998)). These generate so-called holes by an electron transfer process in an electron donating base material (hole transport material). Depending on the number and mobility of holes, the conductivity of the base material varies considerably. Known matrix substances having hole transporting properties include, for example, benzidine derivatives (TPD and the like), starburst amine derivatives (TDATA and the like), and specific metal phthalocyanines (particularly zinc phthalocyanine ZnPc and the like). 2005-167175).

<Light emitting layer in organic electroluminescent element>
The light emitting layer 105 emits light by recombining holes injected from the anode 102 and electrons injected from the cathode 108 between electrodes to which an electric field is applied. The material for forming the light-emitting layer 105 may be a compound that emits light by being excited by recombination of holes and electrons (a light-emitting compound), can form a stable thin film shape, and is in a solid state It is preferable that the compound exhibits a high emission (fluorescence and / or phosphorescence) efficiency.

  The light emitting layer may be either a single layer or a plurality of layers, and each is formed of a light emitting material (host material, dopant material). Each of the host material and the dopant material may be one kind or a plurality of combinations. The dopant material may be included in the host material as a whole, or may be included partially. As a doping method, it can be formed by a co-evaporation method with a host material, but it may be pre-mixed with the host material and then simultaneously deposited.

  The amount of the host material used varies depending on the type of the host material, and may be determined according to the characteristics of the host material. The amount of the host material used is preferably 50 to 99.999% by weight of the entire light emitting material, more preferably 80 to 99.95% by weight, and still more preferably 90 to 99.9% by weight. .

  The amount of dopant material used depends on the type of dopant material, and may be determined according to the characteristics of the dopant material. The standard of the amount of the dopant used is preferably 0.001 to 50% by weight, more preferably 0.05 to 20% by weight, and further preferably 0.1 to 10% by weight of the entire light emitting material. The above range is preferable in that, for example, the concentration quenching phenomenon can be prevented.

  The light emitting material of the light emitting element according to the present embodiment may be either fluorescent or phosphorescent.

  The host material is not particularly limited, but has previously been known as a light emitter, such as fused ring derivatives such as anthracene and pyrene, metal chelated oxinoid compounds such as tris (8-quinolinolato) aluminum, bis Bisstyryl derivatives such as styryl anthracene derivatives and distyrylbenzene derivatives, tetraphenylbutadiene derivatives, coumarin derivatives, oxadiazole derivatives, pyrrolopyridine derivatives, perinone derivatives, cyclopentadiene derivatives, oxadiazole derivatives, thiadiazolopyridine derivatives, pyrrolopyrrole In derivatives, fluorene derivatives, benzofluorene derivatives, and polymer systems, polyphenylene vinylene derivatives, polyparaphenylene derivatives, and polythiophene derivatives are preferably used.

  In addition, as a host material, it can select and use suitably from the compound etc. which were described in the chemical industry June, 2004 issue page 13, and the reference cited up.

  Moreover, it does not specifically limit as dopant material, A known compound can be used and it can select from various materials according to a desired luminescent color. Specifically, for example, condensed ring derivatives such as phenanthrene, anthracene, pyrene, tetracene, pentacene, perylene, naphthopylene, dibenzopyrene, rubrene and chrysene, benzoxazole derivatives, benzothiazole derivatives, benzimidazole derivatives, benzotriazole derivatives, oxazoles Derivatives, oxadiazole derivatives, thiazole derivatives, imidazole derivatives, thiadiazole derivatives, triazole derivatives, pyrazoline derivatives, stilbene derivatives, thiophene derivatives, tetraphenylbutadiene derivatives, cyclopentadiene derivatives, bisstyrylanthracene derivatives, distyrylbenzene derivatives, etc. (JP-A-1-245087), bisstyrylarylene derivatives (JP-A-2-24727) Gazette), diazaindacene derivatives, furan derivatives, benzofuran derivatives, phenylisobenzofuran, dimesitylisobenzofuran, di (2-methylphenyl) isobenzofuran, di (2-trifluoromethylphenyl) isobenzofuran, phenylisobenzofuran, etc. Isobenzofuran derivatives, dibenzofuran derivatives, 7-dialkylaminocoumarin derivatives, 7-piperidinocoumarin derivatives, 7-hydroxycoumarin derivatives, 7-methoxycoumarin derivatives, 7-acetoxycoumarin derivatives, 3-benzothiazolylcoumarin derivatives, 3 -Benzimidazolyl coumarin derivatives, coumarin derivatives such as 3-benzoxazolyl coumarin derivatives, dicyanomethylenepyran derivatives, dicyanomethylenethiopyran derivatives, polymethine derivatives, Nin derivatives, oxobenzoanthracene derivatives, xanthene derivatives, rhodamine derivatives, fluorescein derivatives, pyrylium derivatives, carbostyril derivatives, acridine derivatives, oxazine derivatives, phenylene oxide derivatives, quinacridone derivatives, quinazoline derivatives, pyrrolopyridine derivatives, furopyridine derivatives, 1, Examples include 2,5-thiadiazolopyrene derivatives, pyromethene derivatives, perinone derivatives, pyrrolopyrrole derivatives, squarylium derivatives, violanthrone derivatives, phenazine derivatives, acridone derivatives, deazaflavin derivatives, fluorene derivatives, and benzofluorene derivatives.

  Illustrated for each color light, blue to blue-green dopant materials include naphthalene, anthracene, phenanthrene, pyrene, triphenylene, perylene, fluorene, indene, chrysene and other aromatic hydrocarbon compounds and derivatives thereof, furan, pyrrole, thiophene, Aromatic heterocycles such as silole, 9-silafluorene, 9,9'-spirobisilafluorene, benzothiophene, benzofuran, indole, dibenzothiophene, dibenzofuran, imidazopyridine, phenanthroline, pyrazine, naphthyridine, quinoxaline, pyrrolopyridine, thioxanthene Ring compounds and their derivatives, distyrylbenzene derivatives, tetraphenylbutadiene derivatives, stilbene derivatives, aldazine derivatives, coumarin derivatives, imidazoles, thiazoles, thiadiazos Azole derivatives such as sulfazole, carbazole, oxazole, oxadiazole, triazole and metal complexes thereof and N, N′-diphenyl-N, N′-di (3-methylphenyl) -4,4′-diphenyl-1,1 Examples include aromatic amine derivatives represented by '-diamine.

  Examples of the green to yellow dopant material include coumarin derivatives, phthalimide derivatives, naphthalimide derivatives, perinone derivatives, pyrrolopyrrole derivatives, cyclopentadiene derivatives, acridone derivatives, quinacridone derivatives, and naphthacene derivatives such as rubrene, and the above blue A compound in which a substituent capable of increasing the wavelength such as an aryl group, a heteroaryl group, an arylvinyl group, an amino group, or a cyano group is introduced into the compound exemplified as the blue-green dopant material is also a suitable example.

  Further, examples of the orange to red dopant material include naphthalimide derivatives such as bis (diisopropylphenyl) perylenetetracarboxylic imide, perinone derivatives, rare earth complexes such as Eu complexes having acetylacetone, benzoylacetone and phenanthroline as ligands, 4 -(Dicyanomethylene) -2-methyl-6- (p-dimethylaminostyryl) -4H-pyran and its analogs, metal phthalocyanine derivatives such as magnesium phthalocyanine and aluminum chlorophthalocyanine, rhodamine compounds, deazaflavin derivatives, coumarin derivatives, quinacridone Derivatives, phenoxazine derivatives, oxazine derivatives, quinazoline derivatives, pyrrolopyridine derivatives, squarylium derivatives, violanthrone derivatives, phenazine derivatives, phenoxazones Conductors and thiadiazolopyrene derivatives, etc., and longer wavelengths such as aryl groups, heteroaryl groups, arylvinyl groups, amino groups, and cyano groups can be added to the compounds exemplified above as blue to blue-green and green to yellow dopant materials. A compound into which a substituent is introduced is also a suitable example. Furthermore, a phosphorescent metal complex having iridium represented by tris (2-phenylpyridine) iridium (III) or platinum as a central metal is also a suitable example.

  In addition, as a dopant, it can select and use suitably from the compound etc. which were described in the chemical industry June, 2004 issue page 13, and the reference cited up.

  Among the dopant materials described above, perylene derivatives, borane derivatives, amine-containing styryl derivatives, aromatic amine derivatives, coumarin derivatives, pyran derivatives, iridium complexes, or platinum complexes are particularly preferable.

Examples of perylene derivatives include 3,10-bis (2,6-dimethylphenyl) perylene, 3,10-bis (2,4,6-trimethylphenyl) perylene, 3,10-diphenylperylene, 3,4- Diphenylperylene, 2,5,8,11-tetra-t-butylperylene, 3,4,9,10-tetraphenylperylene, 3- (1'-pyrenyl) -8,11-di (t-butyl) perylene 3- (9′-anthryl) -8,11-di (t-butyl) perylene, 3,3′-bis (8,11-di (t-butyl) perylenyl), and the like.
JP-A-11-97178, JP-A-2000-133457, JP-A-2000-26324, JP-A-2001-267079, JP-A-2001-267078, JP-A-2001-267076, Perylene derivatives described in JP-A No. 2000-34234, JP-A No. 2001-267075, JP-A No. 2001-217077 and the like may be used.

Examples of the borane derivative include 1,8-diphenyl-10- (dimesitylboryl) anthracene, 9-phenyl-10- (dimesitylboryl) anthracene, 4- (9′-anthryl) dimesitylborylnaphthalene, 4- (10 ′). -Phenyl-9'-anthryl) dimesitylborylnaphthalene, 9- (dimesitylboryl) anthracene, 9- (4'-biphenylyl) -10- (dimesitylboryl) anthracene, 9- (4 '-(N-carbazolyl) phenyl) -10- (Dimesitylboryl) anthracene and the like.
Moreover, you may use the borane derivative described in the international publication 2000/40586 pamphlet.

Examples of the amine-containing styryl derivative include N, N, N ′, N′-tetra (4-biphenylyl) -4,4′-diaminostilbene, N, N, N ′, N′-tetra (1-naphthyl). -4,4'-diaminostilbene, N, N, N ', N'-tetra (2-naphthyl) -4,4'-diaminostilbene, N, N'-di (2-naphthyl) -N, N'-Diphenyl-4,4'-diaminostilbene, N, N'-di (9-phenanthryl) -N, N'-diphenyl-4,4'-diaminostilbene, 4,4'-bis [4 "-bis ( Diphenylamino) styryl] -biphenyl, 1,4-bis [4′-bis (diphenylamino) styryl] -benzene, 2,7-bis [4′-bis (diphenylamino) styryl] -9,9-dimethylfluorene 4,4′-bis (9-ethyl-3-carboxy And rubazovinylene) -biphenyl and 4,4′-bis (9-phenyl-3-carbazovinylene) -biphenyl.
In addition, amine-containing styryl derivatives described in JP2003-347056A and JP2001-307884A may be used.

Examples of the aromatic amine derivative include N, N, N, N-tetraphenylanthracene-9,10-diamine, 9,10-bis (4-diphenylamino-phenyl) anthracene, and 9,10-bis (4- Di (1-naphthylamino) phenyl) anthracene, 9,10-bis (4-di (2-naphthylamino) phenyl) anthracene, 10-di-p-tolylamino-9- (4-di-p-tolylamino-1) -Naphthyl) anthracene, 10-diphenylamino-9- (4-diphenylamino-1-naphthyl) anthracene, 10-diphenylamino-9- (6-diphenylamino-2-naphthyl) anthracene, [4- (4-diphenyl) Amino-phenyl) naphthalen-1-yl] -diphenylamine, [4- (4-diphenylamino-phenyl) Naphthalen-1-yl] -diphenylamine, [6- (4-diphenylamino-phenyl) naphthalen-2-yl] -diphenylamine, 4,4′-bis [4-diphenylaminonaphthalen-1-yl] biphenyl, 4, 4'-bis [6-diphenylaminonaphthalen-2-yl] biphenyl, 4,4 "-bis [4-diphenylaminonaphthalen-1-yl] -p-terphenyl, 4,4" -bis [6-diphenyl Aminonaphthalen-2-yl] -p-terphenyl and the like.
Moreover, you may use the aromatic amine derivative described in Unexamined-Japanese-Patent No. 2006-156888.

Examples of the coumarin derivative include coumarin-6 and coumarin-334.
Moreover, you may use the coumarin derivative described in Unexamined-Japanese-Patent No. 2004-43646, Unexamined-Japanese-Patent No. 2001-76876, and Unexamined-Japanese-Patent No. 6-298758.

また、特開2005-126399号公報、特開2005-097283号公報、特開2002-234892号公報、特開2001-220577号公報、特開2001-081090号公報、および特開2001-052869号公報などに記載されたピラン誘導体を用いてもよい。 Examples of the pyran derivative include the following DCM and DCJTB.

Also, JP 2005-126399, JP 2005-097283, JP 2002-234892, JP 2001-220577, JP 2001-081090, and JP 2001-052869. Alternatively, pyran derivatives described in the above may be used.

また、特開2006-089398号公報、特開2006-080419号公報、特開2005-298483号公報、特開2005-097263号公報、および特開2004-111379号公報などに記載されたイリジウム錯体を用いてもよい。 Examples of the iridium complex include Ir (ppy) _{3 described} below.

Further, the iridium complexes described in JP-A-2006-089398, JP-A-2006-080419, JP-A-2005-298483, JP-A-2005-097263, JP-A-2004-111379, etc. It may be used.

また、特開2006-190718号公報、特開2006-128634号公報、特開2006-093542号公報、特開2004-335122号公報、および特開2004-331508号公報などに記載された白金錯体を用いてもよい。 Examples of the platinum complex include the following PtOEP.

Further, the platinum complexes described in JP-A-2006-190718, JP-A-2006-128634, JP-A-2006-093542, JP-A-2004-335122, JP-A-2004-331508, etc. It may be used.

<Electron injection layer and electron transport layer in organic electroluminescence device>
The electron injection layer 107 plays a role of efficiently injecting electrons moving from the cathode 108 into the light emitting layer 105 or the electron transport layer 106. The electron transport layer 106 plays a role of efficiently transporting electrons injected from the cathode 108 or electrons injected from the cathode 108 through the electron injection layer 107 to the light emitting layer 105. The electron transport layer 106 and the electron injection layer 107 are each formed by laminating and mixing one or more electron transport / injection materials or a mixture of the electron transport / injection material and the polymer binder.

  The electron injection / transport layer is a layer that is responsible for injecting electrons from the cathode and further transporting the electrons. It is desirable that the electron injection efficiency is high and the injected electrons are transported efficiently. For this purpose, it is preferable to use a substance that has a high electron affinity, a high electron mobility, excellent stability, and is unlikely to generate trapping impurities during production and use. However, considering the transport balance between holes and electrons, if the role of effectively preventing the holes from the anode from flowing to the cathode side without recombination is mainly played, the electron transport capability is much higher. Even if it is not high, the effect of improving the luminous efficiency is equivalent to that of a material having a high electron transport capability. Therefore, the electron injection / transport layer in this embodiment may include a function of a layer that can efficiently block the movement of holes.

  As a material (electron transport material) for forming the electron transport layer 106 or the electron injection layer 107, a compound represented by the above general formula (1) can be used. The content of the compound represented by the general formula (1) in the electron transport layer 106 or the electron injection layer 107 differs depending on the type of the compound and may be determined according to the characteristics of the compound. The standard of the content of the compound represented by the general formula (1) is preferably 1 to 100% by weight of the total amount of the electron transport layer material (or electron injection layer material), more preferably 10 to 100%. % By weight, more preferably 50 to 100% by weight, and particularly preferably 80 to 100% by weight. When the compound represented by the general formula (1) is not used alone (100% by weight), other materials described in detail below may be mixed.

  Other materials for forming the electron transport layer or electron injection layer include compounds conventionally used as electron transport compounds in photoconductive materials, and known materials used for electron injection layers and electron transport layers of organic electroluminescent devices. Any of these compounds can be selected and used.

  Materials used for the electron transport layer or the electron injection layer include compounds composed of aromatic rings or heteroaromatic rings composed of one or more atoms selected from carbon, hydrogen, oxygen, sulfur, silicon, and phosphorus, and pyrrole derivatives. And at least one selected from the condensed ring derivatives thereof and metal complexes having electron-accepting nitrogen. Specifically, condensed ring aromatic ring derivatives such as naphthalene and anthracene, styryl aromatic ring derivatives represented by 4,4′-bis (diphenylethenyl) biphenyl, perinone derivatives, coumarin derivatives, naphthalimide derivatives, anthraquinones And quinone derivatives such as diphenoquinone, phosphorus oxide derivatives, carbazole derivatives, and indole derivatives. Examples of metal complexes having electron-accepting nitrogen include hydroxyazole complexes such as hydroxyphenyloxazole complexes, azomethine complexes, tropolone metal complexes, flavonol metal complexes, and benzoquinoline metal complexes. These materials can be used alone or in combination with different materials. Among them, anthracene derivatives such as 9,10-bis (2-naphthyl) anthracene, styryl aromatic ring derivatives such as 4,4′-bis (diphenylethenyl) biphenyl, 4,4′-bis (N-carbazolyl) biphenyl A carbazole derivative such as 1,3,5-tris (N-carbazolyl) benzene is preferably used from the viewpoint of durability.

  Specific examples of other electron transfer compounds include pyridine derivatives, naphthalene derivatives, anthracene derivatives, phenanthroline derivatives, perinone derivatives, coumarin derivatives, naphthalimide derivatives, anthraquinone derivatives, diphenoquinone derivatives, diphenylquinone derivatives, perylene derivatives, oxadiazoles. Derivatives (1,3-bis [(4-t-butylphenyl) 1,3,4-oxadiazolyl] phenylene, etc.), thiophene derivatives, triazole derivatives (N-naphthyl-2,5-diphenyl-1,3,4- Triazole, etc.), thiadiazole derivatives, metal complexes of oxine derivatives, quinolinol metal complexes, quinoxaline derivatives, polymers of quinoxaline derivatives, benzazole compounds, gallium complexes, pyrazole derivatives, perfluorinated phen Lene derivatives, triazine derivatives, pyrazine derivatives, benzoquinoline derivatives (2,2′-bis (benzo [h] quinolin-2-yl) -9,9′-spirobifluorene, etc.), imidazopyridine derivatives, borane derivatives, benzo Imidazole derivatives (such as tris (N-phenylbenzimidazol-2-yl) benzene), benzoxazole derivatives, benzothiazole derivatives, quinoline derivatives, oligopyridine derivatives such as terpyridine, bipyridine derivatives, terpyridine derivatives (1,3-bis (4 '-(2,2': 6'2 "-terpyridinyl)) benzene), naphthyridine derivatives (bis (1-naphthyl) -4- (1,8-naphthyridin-2-yl) phenylphosphine oxide), aldazine Derivatives, carbazole derivatives, India Le derivatives, phosphorus oxide derivatives, such as bis-styryl derivatives.

  In addition, metal complexes having electron-accepting nitrogen can also be used, such as hydroxyazole complexes such as quinolinol-based metal complexes and hydroxyphenyloxazole complexes, azomethine complexes, tropolone metal complexes, flavonol metal complexes, and benzoquinoline metal complexes. can give.

  Although the above-mentioned materials are used alone, they may be mixed with different materials.

  Among the materials described above, quinolinol-based metal complexes, bipyridine derivatives, phenanthroline derivatives, or borane derivatives are preferable.

式中、Ｒ^１〜Ｒ^６は水素または置換基であり、ＭはＬｉ、Ａｌ、Ｇａ、ＢｅまたはＺｎであり、ｎは１〜３の整数である。 The quinolinol-based metal complex is a compound represented by the following general formula (E-1).

In the formula, R ^{1 to} R ⁶ are hydrogen or a substituent, M is Li, Al, Ga, Be, or Zn, and n is an integer of 1 to 3.

  Specific examples of the quinolinol-based metal complex include 8-quinolinol lithium, tris (8-quinolinolato) aluminum, tris (4-methyl-8-quinolinolato) aluminum, tris (5-methyl-8-quinolinolato) aluminum, tris (3 , 4-dimethyl-8-quinolinolato) aluminum, tris (4,5-dimethyl-8-quinolinolato) aluminum, tris (4,6-dimethyl-8-quinolinolato) aluminum, bis (2-methyl-8-quinolinolato) ( Phenolate) aluminum, bis (2-methyl-8-quinolinolato) (2-methylphenolato) aluminum, bis (2-methyl-8-quinolinolato) (3-methylphenolato) aluminum, bis (2-methyl-8- Quinolinolato) (4-me Ruphenolate) aluminum, bis (2-methyl-8-quinolinolato) (2-phenylphenolate) aluminum, bis (2-methyl-8-quinolinolato) (3-phenylphenolate) aluminum, bis (2-methyl-8- Quinolinolato) (4-phenylphenolate) aluminum, bis (2-methyl-8-quinolinolato) (2,3-dimethylphenolate) aluminum, bis (2-methyl-8-quinolinolato) (2,6-dimethylphenolate) ) Aluminum, bis (2-methyl-8-quinolinolato) (3,4-dimethylphenolate) aluminum, bis (2-methyl-8-quinolinolato) (3,5-dimethylphenolate) aluminum, bis (2-methyl) -8-quinolinolate) (3,5-di-tert-butyl) Ruphenolate) aluminum, bis (2-methyl-8-quinolinolato) (2,6-diphenylphenolate) aluminum, bis (2-methyl-8-quinolinolato) (2,4,6-triphenylphenolate) aluminum, bis (2-Methyl-8-quinolinolato) (2,4,6-trimethylphenolate) aluminum, bis (2-methyl-8-quinolinolato) (2,4,5,6-tetramethylphenolate) aluminum, bis ( 2-methyl-8-quinolinolato) (1-naphtholato) aluminum, bis (2-methyl-8-quinolinolato) (2-naphtholato) aluminum, bis (2,4-dimethyl-8-quinolinolato) (2-phenylphenolate) ) Aluminum, bis (2,4-dimethyl-8-quinolinolate) ) (3-phenylphenolate) aluminum, bis (2,4-dimethyl-8-quinolinolato) (4-phenylphenolate) aluminum, bis (2,4-dimethyl-8-quinolinolato) (3,5-dimethylphenol) Lat) aluminum, bis (2,4-dimethyl-8-quinolinolato) (3,5-di-t-butylphenolate) aluminum, bis (2-methyl-8-quinolinolato) aluminum-μ-oxo-bis (2 -Methyl-8-quinolinolato) aluminum, bis (2,4-dimethyl-8-quinolinolato) aluminum-μ-oxo-bis (2,4-dimethyl-8-quinolinolato) aluminum, bis (2-methyl-4-ethyl) -8-quinolinolato) aluminum-μ-oxo-bis (2-methyl-4-ethyl-8) Quinolinolato) aluminum, bis (2-methyl-4-methoxy-8-quinolinolato) aluminum-μ-oxo-bis (2-methyl-4-methoxy-8-quinolinolato) aluminum, bis (2-methyl-5-cyano- 8-quinolinolato) aluminum-μ-oxo-bis (2-methyl-5-cyano-8-quinolinolato) aluminum, bis (2-methyl-5-trifluoromethyl-8-quinolinolato) aluminum-μ-oxo-bis ( 2-methyl-5-trifluoromethyl-8-quinolinolato) aluminum, bis (10-hydroxybenzo [h] quinoline) beryllium and the like.

式中、Ｇは単なる結合手またはｎ価の連結基を表し、ｎは２〜８の整数である。また、ピリジン−ピリジンまたはピリジン−Ｇの結合に用いられない炭素原子は置換されていてもよい。 A bipyridine derivative is a compound represented by the following general formula (E-2).

In the formula, G represents a simple bond or an n-valent linking group, and n is an integer of 2 to 8. Carbon atoms that are not used for bonding of pyridine-pyridine or pyridine-G may be substituted.

Examples of G in the general formula (E-2) include the following structural formulas. In addition, R in the following structural formula is each independently hydrogen, methyl, ethyl, isopropyl, cyclohexyl, phenyl, 1-naphthyl, 2-naphthyl, biphenylyl, or terphenylyl.

  Specific examples of the pyridine derivative include 2,5-bis (2,2′-pyridin-6-yl) -1,1-dimethyl-3,4-diphenylsilole, 2,5-bis (2,2′- Pyridin-6-yl) -1,1-dimethyl-3,4-dimesitylsilole, 2,5-bis (2,2′-pyridin-5-yl) -1,1-dimethyl-3,4 Diphenylsilole, 2,5-bis (2,2′-pyridin-5-yl) -1,1-dimethyl-3,4-dimesitylsilole 9,10-di (2,2′-pyridine-6- Yl) anthracene, 9,10-di (2,2′-pyridin-5-yl) anthracene, 9,10-di (2,3′-pyridin-6-yl) anthracene, 9,10-di (2, 3'-Pyridin-5-yl) anthracene, 9,10-di (2,3'-pyridine-6) Yl) -2-phenylanthracene, 9,10-di (2,3′-pyridin-5-yl) -2-phenylanthracene, 9,10-di (2,2′-pyridin-6-yl) -2 -Phenylanthracene, 9,10-di (2,2'-pyridin-5-yl) -2-phenylanthracene, 9,10-di (2,4'-pyridin-6-yl) -2-phenylanthracene, 9,10-di (2,4′-pyridin-5-yl) -2-phenylanthracene, 9,10-di (3,4′-pyridin-6-yl) -2-phenylanthracene, 9,10- Di (3,4'-pyridin-5-yl) -2-phenylanthracene, 3,4-diphenyl-2,5-di (2,2'-pyridin-6-yl) thiophene, 3,4-diphenyl- 2,5-di (2,3′-pyridine- - yl) thiophene, 6'6 "- di (2-pyridyl) 2,2 ': 4', 4": 2 ", 2" '- like quaterphenyl pyridine.

式中、Ｒ^１〜Ｒ^８は水素または置換基であり、隣接する基は互いに結合して縮合環を形成してもよく、Ｇは単なる結合手またはｎ価の連結基を表し、ｎは２〜８の整数である。また、一般式（Ｅ−３−２）のＧとしては、例えば、ビピリジン誘導体の欄で説明したものと同じものがあげられる。 A phenanthroline derivative is a compound represented by the following general formula (E-3-1) or (E-3-2).

In the formula, R ^{1 to} R ⁸ are hydrogen or a substituent, adjacent groups may be bonded to each other to form a condensed ring, G represents a simple bond or an n-valent linking group, and n represents 2 It is an integer of ~ 8. Moreover, as G of general formula (E-3-2), the same thing as what was demonstrated in the column of the bipyridine derivative is mention | raise | lifted, for example.

  Specific examples of the phenanthroline derivative include 4,7-diphenyl-1,10-phenanthroline, 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline, 9,10-di (1,10-phenanthroline- 2-yl) anthracene, 2,6-di (1,10-phenanthroline-5-yl) pyridine, 1,3,5-tri (1,10-phenanthroline-5-yl) benzene, 9,9′-difluor -Bis (1,10-phenanthroline-5-yl), bathocuproin, 1,3-bis (2-phenyl-1,10-phenanthroline-9-yl) benzene and the like.

  In particular, the case where a phenanthroline derivative is used for an electron transport layer and an electron injection layer will be described. In order to obtain stable light emission over a long period of time, a material excellent in thermal stability and thin film formation is desired, and among phenanthroline derivatives, the substituent itself has a three-dimensional structure, or a phenanthroline skeleton or Those having a three-dimensional structure by steric repulsion with an adjacent substituent or those having a plurality of phenanthroline skeletons linked to each other are preferred. Furthermore, when linking a plurality of phenanthroline skeletons, a compound containing a conjugated bond, a substituted or unsubstituted aromatic hydrocarbon, or a substituted or unsubstituted aromatic heterocycle in the linking unit is more preferable.

式中、Ｒ^１１およびＲ^１２は、それぞれ独立して、水素原子、アルキル基、置換されていてもよいアリール基、置換シリル基、置換されていてもよい窒素含有複素環基、またはシアノ基の少なくとも一つであり、Ｒ^１３〜Ｒ^１６は、それぞれ独立して、置換されていてもよいアルキル基、または置換されていてもよいアリール基であり、Ｘは、置換されていてもよいアリーレン基であり、Ｙは、置換されていてもよい炭素数１６以下のアリール基、置換ボリル基、または置換されていてもよいカルバゾール基であり、そして、ｎはそれぞれ独立して０〜３の整数である。 The borane derivative is a compound represented by the following general formula (E-4), and is disclosed in detail in JP-A-2007-27587.

In the formula, each of R ¹¹ and R ¹² independently represents a hydrogen atom, an alkyl group, an optionally substituted aryl group, a substituted silyl group, an optionally substituted nitrogen-containing heterocyclic group, or a cyano group. At least one, R ^{13 to} R ¹⁶ are each independently an optionally substituted alkyl group or an optionally substituted aryl group, and X is an optionally substituted arylene group And Y is an optionally substituted aryl group having 16 or less carbon atoms, a substituted boryl group, or an optionally substituted carbazole group, and n is each independently an integer of 0 to 3 is there.

式中、Ｒ^１１およびＲ^１２は、それぞれ独立して、水素原子、アルキル基、置換されていてもよいアリール基、置換シリル基、置換されていてもよい窒素含有複素環基、またはシアノ基の少なくとも一つであり、Ｒ^１３〜Ｒ^１６は、それぞれ独立して、置換されていてもよいアルキル基、または置換されていてもよいアリール基であり、Ｒ^２１およびＲ^２２は、それぞれ独立して、水素原子、アルキル基、置換されていてもよいアリール基、置換シリル基、置換されていてもよい窒素含有複素環基、またはシアノ基の少なくとも一つであり、Ｘ^１は、置換されていてもよい炭素数２０以下のアリーレン基であり、ｎはそれぞれ独立して０〜３の整数であり、そして、ｍはそれぞれ独立して０〜４の整数である。 Among the compounds represented by the general formula (E-4), the compounds represented by the following general formula (E-4-1), and further the following general formulas (E-4-1-1) to (E-4) The compound represented by -1-4) is preferable. Specific examples include 9- [4- (4-Dimesitylborylnaphthalen-1-yl) phenyl] carbazole, 9- [4- (4-Dimesitylborylnaphthalen-1-yl) naphthalen-1-yl. Carbazole and the like.

In the formula, each of R ¹¹ and R ¹² independently represents a hydrogen atom, an alkyl group, an optionally substituted aryl group, a substituted silyl group, an optionally substituted nitrogen-containing heterocyclic group, or a cyano group. At least one, R ^{13 to} R ¹⁶ are each independently an optionally substituted alkyl group or an optionally substituted aryl group, and R ²¹ and R ²² are each independently , A hydrogen atom, an alkyl group, an optionally substituted aryl group, a substituted silyl group, an optionally substituted nitrogen-containing heterocyclic group, or a cyano group, and X ¹ is a substituted Or an arylene group having 20 or less carbon atoms, n is each independently an integer of 0 to 3, and m is each independently an integer of 0 to 4.

各式中、Ｒ^３１〜Ｒ^３４は、それぞれ独立して、メチル、イソプロピルまたはフェニルのいずれかであり、そして、Ｒ^３５およびＲ^３６は、それぞれ独立して、水素、メチル、イソプロピルまたはフェニルのいずれかである。

In each formula, R ^{31 to} R ³⁴ are each independently methyl, isopropyl or phenyl, and R ³⁵ and R ³⁶ are each independently hydrogen, methyl, isopropyl or phenyl. It is.

式中、Ｒ^１１およびＲ^１２は、それぞれ独立して、水素原子、アルキル基、置換されていてもよいアリール基、置換シリル基、置換されていてもよい窒素含有複素環基、またはシアノ基の少なくとも一つであり、Ｒ^１３〜Ｒ^１６は、それぞれ独立して、置換されていてもよいアルキル基、または置換されていてもよいアリール基であり、Ｘ^１は、置換されていてもよい炭素数２０以下のアリーレン基であり、そして、ｎはそれぞれ独立して０〜３の整数である。 Among the compounds represented by the general formula (E-4), a compound represented by the following general formula (E-4-2), and a compound represented by the following general formula (E-4-2-1) Is preferred.

In the formula, each of R ¹¹ and R ¹² independently represents a hydrogen atom, an alkyl group, an optionally substituted aryl group, a substituted silyl group, an optionally substituted nitrogen-containing heterocyclic group, or a cyano group. At least one, R ^{13 to} R ¹⁶ are each independently an optionally substituted alkyl group or an optionally substituted aryl group, and X ¹ is an optionally substituted carbon. An arylene group having a number of 20 or less, and each n is independently an integer of 0 to 3.

式中、Ｒ^３１〜Ｒ^３４は、それぞれ独立して、メチル、イソプロピルまたはフェニルのいずれかであり、そして、Ｒ^３５およびＲ^３６は、それぞれ独立して、水素、メチル、イソプロピルまたはフェニルのいずれかである。

In the formula, R ^{31 to} R ³⁴ are each independently any of methyl, isopropyl or phenyl, and R ³⁵ and R ³⁶ are each independently any of hydrogen, methyl, isopropyl or phenyl It is.

式中、Ｒ^１１およびＲ^１２は、それぞれ独立して、水素原子、アルキル基、置換されていてもよいアリール基、置換シリル基、置換されていてもよい窒素含有複素環基、またはシアノ基の少なくとも一つであり、Ｒ^１３〜Ｒ^１６は、それぞれ独立して、置換されていてもよいアルキル基、または置換されていてもよいアリール基であり、Ｘ^１は、置換されていてもよい炭素数１０以下のアリーレン基であり、Ｙ^１は、置換されていてもよい炭素数１４以下のアリール基であり、そして、ｎはそれぞれ独立して０〜３の整数である。 Among the compounds represented by the general formula (E-4), a compound represented by the following general formula (E-4-3-3), and further, the following general formula (E-4-3-1) or (E-4) The compound represented by -3-2) is preferable.

In the formula, each of R ¹¹ and R ¹² independently represents a hydrogen atom, an alkyl group, an optionally substituted aryl group, a substituted silyl group, an optionally substituted nitrogen-containing heterocyclic group, or a cyano group. At least one, R ^{13 to} R ¹⁶ are each independently an optionally substituted alkyl group or an optionally substituted aryl group, and X ¹ is an optionally substituted carbon. It is an arylene group having several tens or less, Y ¹ is an optionally substituted aryl group having 14 or less carbon atoms, and n is each independently an integer of 0 to 3.

各式中、Ｒ^３１〜Ｒ^３４は、それぞれ独立して、メチル、イソプロピルまたはフェニルのいずれかであり、そして、Ｒ^３５およびＲ^３６は、それぞれ独立して、水素、メチル、イソプロピルまたはフェニルのいずれかである。

In each formula, R ^{31 to} R ³⁴ are each independently methyl, isopropyl or phenyl, and R ³⁵ and R ³⁶ are each independently hydrogen, methyl, isopropyl or phenyl. It is.

式中、Ａｒ^１〜Ａｒ^３はそれぞれ独立に水素または置換されてもよい炭素数６〜３０のアリールである。特に、Ａｒ^１が置換されてもよいアントリルであるベンゾイミダゾール誘導体が好ましい。 The benzimidazole derivative is a compound represented by the following general formula (E-5).

In the formula, Ar ^{1 to} Ar ³ are each independently hydrogen or aryl having 6 to 30 carbon atoms which may be substituted. In particular, a benzimidazole derivative which is anthryl optionally substituted with Ar ¹ is preferable.

  Specific examples of the aryl having 6 to 30 carbon atoms include phenyl, 1-naphthyl, 2-naphthyl, acenaphthylene-1-yl, acenaphthylene-3-yl, acenaphthylene-4-yl, acenaphthylene-5-yl, and fluorene-1- Yl, fluoren-2-yl, fluoren-3-yl, fluoren-4-yl, fluoren-9-yl, phenalen-1-yl, phenalen-2-yl, 1-phenanthryl, 2-phenanthryl, 3-phenanthryl, 4-phenanthryl, 9-phenanthryl, 1-anthryl, 2-anthryl, 9-anthryl, fluoranthen-1-yl, fluoranthen-2-yl, fluoranthen-3-yl, fluoranthen-7-yl, fluoranthen-8-yl, Triphenylene-1-yl, triphenylene-2-yl, pyreth -1-yl, pyren-2-yl, pyren-4-yl, chrysen-1-yl, chrysen-2-yl, chrysen-3-yl, chrysen-4-yl, chrysen-5-yl, chrysene-6 -Yl, naphthacene-1-yl, naphthacene-2-yl, naphthacene-5-yl, perylene-1-yl, perylene-2-yl, perylene-3-yl, pentacene-1-yl, pentasen-2-yl , Pentacene-5-yl and pentacene-6-yl.

  Specific examples of the benzimidazole derivative include 1-phenyl-2- (4- (10-phenylanthracen-9-yl) phenyl) -1H-benzo [d] imidazole, 2- (4- (10- (naphthalene-2) -Yl) anthracen-9-yl) phenyl) -1-phenyl-1H-benzo [d] imidazole, 2- (3- (10- (naphthalen-2-yl) anthracen-9-yl) phenyl) -1- Phenyl-1H-benzo [d] imidazole, 5- (10- (naphthalen-2-yl) anthracen-9-yl) -1,2-diphenyl-1H-benzo [d] imidazole, 1- (4- (10 -(Naphthalen-2-yl) anthracen-9-yl) phenyl) -2-phenyl-1H-benzo [d] imidazole, 2- (4- (9,10-di (naphthalene) 2-yl) anthracen-2-yl) phenyl) -1-phenyl-1H-benzo [d] imidazole, 1- (4- (9,10-di (naphthalen-2-yl) anthracen-2-yl) phenyl ) -2-phenyl-1H-benzo [d] imidazole, 5- (9,10-di (naphthalen-2-yl) anthracen-2-yl) -1,2-diphenyl-1H-benzo [d] imidazole is there.

  The electron transport layer or the electron injection layer may further contain a substance capable of reducing the material forming the electron transport layer or the electron injection layer. As this reducing substance, various substances can be used as long as they have a certain reducing ability. For example, alkali metal, alkaline earth metal, rare earth metal, alkali metal oxide, alkali metal halide, alkali From the group consisting of earth metal oxides, alkaline earth metal halides, rare earth metal oxides, rare earth metal halides, alkali metal organic complexes, alkaline earth metal organic complexes and rare earth metal organic complexes At least one selected can be suitably used.

  Preferred reducing substances include alkali metals such as Na (work function 2.36 eV), K (2.28 eV), Rb (2.16 eV) or Cs (1.95 eV), and Ca (2. 9eV), Sr (2.0 to 2.5 eV) or Ba (2.52 eV), and alkaline earth metals such as those having a work function of 2.9 eV or less are particularly preferable. Among these, a more preferable reducing substance is an alkali metal of K, Rb or Cs, more preferably Rb or Cs, and most preferably Cs. These alkali metals have particularly high reducing ability, and by adding a relatively small amount to the material forming the electron transport layer or the electron injection layer, the luminance of the organic EL element can be improved and the lifetime can be extended. Further, as a reducing substance having a work function of 2.9 eV or less, a combination of two or more alkali metals is also preferable. Particularly, a combination containing Cs, such as Cs and Na, Cs and K, Cs and Rb, or A combination of Cs, Na and K is preferred. By containing Cs, the reducing ability can be efficiently exhibited, and by adding to the material for forming the electron transport layer or the electron injection layer, the luminance of the organic EL element can be improved and the lifetime can be extended.

<Cathode in organic electroluminescence device>
The cathode 108 serves to inject electrons into the light emitting layer 105 through the electron injection layer 107 and the electron transport layer 106.

  The material for forming the cathode 108 is not particularly limited as long as it can efficiently inject electrons into the organic layer, but the same material as that for forming the anode 102 can be used. Among them, metals such as tin, magnesium, indium, calcium, aluminum, silver, copper, nickel, chromium, gold, platinum, iron, zinc, lithium, sodium, potassium, cesium and magnesium or alloys thereof (magnesium-silver alloy) , Magnesium-indium alloys, aluminum-lithium alloys such as lithium fluoride / aluminum) are preferred. Lithium, sodium, potassium, cesium, calcium, magnesium, or alloys containing these low work function metals are effective for increasing the electron injection efficiency and improving device characteristics. However, these low work function metals are often often unstable in the atmosphere. In order to improve this point, for example, a method is known in which an organic layer is doped with a small amount of lithium, cesium or magnesium and a highly stable electrode is used. As other dopants, inorganic salts such as lithium fluoride, cesium fluoride, lithium oxide, and cesium oxide can also be used. However, it is not limited to these.

  Furthermore, for electrode protection, metals such as platinum, gold, silver, copper, iron, tin, aluminum and indium, or alloys using these metals, and inorganic materials such as silica, titania and silicon nitride, polyvinyl alcohol, vinyl chloride Lamination of hydrocarbon polymer compounds and the like is a preferred example. The method for producing these electrodes is not particularly limited as long as conduction can be achieved, such as resistance heating, electron beam, sputtering, ion plating, and coating.

<Binder that may be used in each layer>
The materials used for the hole injection layer, hole transport layer, light emitting layer, electron transport layer and electron injection layer can form each layer alone, but as a polymer binder, polyvinyl chloride, polycarbonate, Polystyrene, poly (N-vinylcarbazole), polymethyl methacrylate, polybutyl methacrylate, polyester, polysulfone, polyphenylene oxide, polybutadiene, hydrocarbon resin, ketone resin, phenoxy resin, polyamide, ethyl cellulose, vinyl acetate resin, ABS resin, polyurethane resin It can also be used by dispersing it in solvent-soluble resins such as phenol resins, xylene resins, petroleum resins, urea resins, melamine resins, unsaturated polyester resins, alkyd resins, epoxy resins, silicone resins, etc. is there.

<Method for producing organic electroluminescent element>
Each layer constituting the organic electroluminescent element is formed by a method such as vapor deposition, resistance heating vapor deposition, electron beam vapor deposition, sputtering, molecular lamination method, printing method, spin coating method or cast method, coating method, etc. It can be formed by using a thin film. The thickness of each layer formed in this way is not particularly limited and can be appropriately set according to the properties of the material, but is usually in the range of 2 nm to 5000 nm. The film thickness can usually be measured with a crystal oscillation type film thickness measuring device or the like. When a thin film is formed using a vapor deposition method, the vapor deposition conditions vary depending on the type of material, the target crystal structure and association structure of the film, and the like. Deposition conditions generally include boat heating temperature +50 to + 400 ° C., vacuum degree 10 ⁻⁶ to 10 ⁻³ Pa, deposition rate 0.01 to 50 nm / sec, substrate temperature −150 to + 300 ° C., film thickness 2 nm to 5 μm. It is preferable to set appropriately within the range.

  Next, as an example of a method for producing an organic electroluminescent device, an organic electric field composed of an anode / hole injection layer / hole transport layer / a light emitting layer composed of a host material and a dopant material / electron transport layer / electron injection layer / cathode. A method for manufacturing a light-emitting element will be described. A thin film of an anode material is formed on a suitable substrate by vapor deposition or the like to produce an anode, and then a thin film of a hole injection layer and a hole transport layer is formed on the anode. A host material and a dopant material are co-evaporated to form a thin film to form a light emitting layer. An electron transport layer and an electron injection layer are formed on the light emitting layer, and a thin film made of a cathode material is formed by vapor deposition. By forming it as a cathode, a desired organic electroluminescent element can be obtained. In the preparation of the above-described organic electroluminescence device, the order of preparation may be reversed, and the cathode, electron injection layer, electron transport layer, light emitting layer, hole transport layer, hole injection layer, and anode may be fabricated in this order. Is possible.

  When a DC voltage is applied to the organic electroluminescent device thus obtained, the anode may be applied with a positive polarity and the cathode with a negative polarity. When a voltage of about 2 to 40 V is applied, the organic electroluminescent device is transparent or translucent. Luminescence can be observed from the electrode side (anode or cathode, and both). The organic electroluminescence device emits light when a pulse current or an alternating current is applied. The alternating current waveform to be applied may be arbitrary.

<Application examples of organic electroluminescent devices>
The present invention can also be applied to a display device provided with an organic electroluminescent element or a lighting device provided with an organic electroluminescent element.
A display device or an illuminating device including an organic electroluminescent element can be manufactured by a known method such as connecting the organic electroluminescent element according to the present embodiment and a known driving device. It can be driven by appropriately using a known driving method such as driving.

  Examples of the display device include a panel display such as a color flat panel display, and a flexible display such as a flexible color organic electroluminescence (EL) display (for example, JP-A-10-335066 and JP-A-2003-321546). Gazette, JP-A-2004-281086, etc.). Examples of the display method of the display include a matrix and / or segment method. Note that the matrix display and the segment display may coexist in the same panel.

  A matrix means a pixel in which pixels for display are two-dimensionally arranged such as a lattice or a mosaic, and displays a character or an image with a set of pixels. The shape and size of the pixel are determined by the application. For example, a square pixel with a side of 300 μm or less is usually used for displaying images and characters on a personal computer, monitor, TV, and a pixel with a side of mm order for a large display such as a display panel. become. In monochrome display, pixels of the same color may be arranged. However, in color display, red, green, and blue pixels are displayed side by side. In this case, there are typically a delta type and a stripe type. The matrix driving method may be either a line sequential driving method or an active matrix. The line-sequential driving has an advantage that the structure is simple. However, the active matrix may be superior in consideration of the operation characteristics, so that it is necessary to properly use it depending on the application.

  In the segment system (type), a pattern is formed so as to display predetermined information, and a predetermined region is caused to emit light. For example, the time and temperature display in a digital clock or a thermometer, the operation state display of an audio device or an electromagnetic cooker, the panel display of an automobile, and the like can be mentioned.

  Examples of the illuminating device include an illuminating device such as indoor lighting, a backlight of a liquid crystal display device, and the like (for example, JP 2003-257621 A, JP 2003-277741 A, JP 2004-119211 A). Etc.) The backlight is used mainly for the purpose of improving the visibility of a display device that does not emit light, and is used for a liquid crystal display device, a clock, an audio device, an automobile panel, a display board, a sign, and the like. In particular, as a backlight for liquid crystal display devices, especially personal computers for which thinning is an issue, considering that conventional methods are made of fluorescent lamps and light guide plates, it is difficult to reduce the thickness. The backlight using the light emitting element according to the embodiment is thin and lightweight.

  First, synthesis examples of pyridylphenyl-substituted anthracene compounds used in the examples are described below.

<Synthesis Example of Compound Represented by Formula (1-1-10)>

<Synthesis of 4- (4-bromophenyl) pyridine>
To a flask containing 4-iodopyridine (7.0 g) and THF (32 ml), a 2M isopropylmagnesium chloride THF solution (18.8 ml) was cooled in an ice bath and added dropwise with stirring under a nitrogen atmosphere. After completion of the dropwise addition, zinc chloride tetramethylethylenediamine complex (9.1 g) was added while cooling with ice water and stirring. Thereafter, the mixture was stirred at room temperature for 0.5 hour, 1,4-dibromobenzene (12.1 g) and Pd (PPh ₃ ) ₄ (0.2 g) were added, and the mixture was stirred at reflux temperature for 2 hours. In order to cool the reaction solution to room temperature and remove the metal ions of the catalyst, a solution of ethylenediaminetetraacetic acid / tetrasodium salt dihydrate corresponding to approximately 2 moles of the target compound in an appropriate amount of water ( Hereinafter, abbreviated as EDTA · 4Na aqueous solution). Further, ethyl acetate was added to carry out a liquid separation operation. The organic layer was concentrated with an evaporator and purified by silica gel chromatography (toluene / ethyl acetate = 80/20 (volume ratio)), and then washed with heptane to give 4- (4-bromophenyl) pyridine (5.6 g). Obtained.

<2,2 ′-(2-([1,1 ′: 3 ′, 1 ″ -terphenyl] -5′-yl) anthracene-9,10-diyl) bis (4,4,5,5- Synthesis of tetramethyl-1,3,2-dioxaborolane)
This boronic ester was synthesized according to Scheme 1-1 to Scheme 1-5 described in JP-A-2009-275013 (see pages 7 to 10 of the publication, paragraphs [0014] to [0017]).

<Synthesis of Compound Represented by Formula (1-1-10)>
2,2 ′-(2-([1,1 ′: 3 ′, 1 ″ -terphenyl] -5′-yl) anthracene-9,10-diyl) bis (4,4,5,5-tetra Methyl-1,3,2-dioxaborolane) (67.0 g), 4- (4-bromophenyl) pyridine (57.4 g), Pd (PPh ₃ ) ₄ (5.9 g), tripotassium phosphate (86. 6 g), 1,2,4-trimethylbenzene (350 ml), t-butyl alcohol (70 ml) and water (14 ml) were placed in a flask and stirred at reflux temperature for 2 hours under a nitrogen atmosphere. After completion of heating, the reaction solution was cooled to room temperature, and water and heptane were added and filtered. The obtained solid was washed with water and methanol, and further washed with toluene and chlorobenzene. Further, the compound “4,4 ′-((2- [1,1 ′: 3 ′, 1 ″ -terphenyl] -5′-yl represented by (1-1-10) was recrystallized from chlorobenzene. ) Anthracene-9,10-diyl) bis (4,1-phenylene) dipyridine "(22.1 g).

The structure of the pyridylphenyl substituted anthracene compound obtained by NMR measurement was confirmed.
¹ H-NMR (CDCl ₃ ): δ = 8.76 (m, 4H), 8.01 (m, 1H), 7.93 (t, 4H), 7.86 (d, 1H), 7.65 −7.81 (m, 14H), 7.62 (m, 4H), 7.35 to 7.45 (m, 8H).

<Synthesis Example of Compound Represented by Formula (1-1-7)>

<Synthesis of 2- (naphthalen-2-yl) anthracene>
2-bromoanthracene (31.1 g), 2-naphthaleneboronic acid, bis (dibenzylideneacetone) palladium (0) (0.35 g), tricyclohexylphosphine (0.34 g), tripotassium phosphate (77.1 g) 1,2,4-trimethylbenzene (311 ml), t-butyl alcohol (62 ml) and water (12 ml) were placed in a flask and stirred at reflux temperature for 1.5 hours under a nitrogen atmosphere. After completion of heating, the reaction solution was cooled to room temperature, and water and heptane were added and filtered. The obtained solid was further washed with water and heptane, and further washed with methanol to obtain 2- (naphthalen-2-yl) anthracene (36.7 g).

<Synthesis of 9,10-dibromo-2- (naphthalen-2-yl) anthracene>
Bromine (40.0 g) was added dropwise to a flask containing 2- (naphthalen-2-yl) anthracene (36.7 g) and chloroform (600 ml). After completion of the dropwise addition, the mixture was stirred at room temperature for 9 and a half hours, and water, sodium bisulfite and sodium hydrogen carbonate were added to stop the reaction. Chloroform was distilled off from the reaction solution under reduced pressure, followed by filtration. The resulting solid was washed with water, heptane, then with methanol, and further with toluene. Then, recrystallization from xylene gave 9,10-dibromo-2- (naphthalen-2-yl) anthracene (32.1 g).

<Synthesis of 2,2 ′-(2- (naphthalen-2-yl) anthracene-9,10-diyl) bis (4,4,5,5-tetramethyl-1,3,2-dioxaborolane)>
9,10-dibromo-2- (naphthalen-2-yl) anthracene (32.1 g), bispinacolatodiboron (44.2 g), bis (dibenzylideneacetone) palladium (0) (2.0 g), tri A flask containing cyclohexylphosphine (2.0 g), potassium acetate (27.3 g), potassium carbonate (19.2 g) and anisole (420 ml) was heated and stirred at 130 ° C. for 3 hours under a nitrogen atmosphere. After completion of the heating, the reaction solution was cooled to room temperature, and suction filtered using a Kiriyama funnel with celite. Crystals obtained by adding heptane to the filtrate were filtered off, and 2,2 ′-(2- (naphthalen-2-yl) anthracene-9,10-diyl) bis (4,4,5,5-tetramethyl) was obtained. -1,3,2-dioxaborolane) (31.5 g) was obtained.

<Synthesis of Compound Represented by Formula (1-1-7)>
2,2 ′-(2- (naphthalen-2-yl) anthracene-9,10-diyl) bis (4,4,5,5-tetramethyl-1,3,2-dioxaborolane) (36.5 g), 4- (4-bromophenyl) pyridine (36.9 g), Pd (PPh ₃ ) ₄ (3.8 g), tripotassium phosphate (55.7 g), 1,2,4-trimethylbenzene (185 ml), t -Butyl alcohol (37 ml) and water (7.4 ml) were placed in a flask and stirred at reflux temperature for 1 hour under a nitrogen atmosphere. After completion of heating, the reaction solution was cooled to room temperature, and water and heptane were added and filtered. The obtained solid was washed with water and methanol and then recrystallized from nitrobenzene to give the compound “4,4 ′-((2-naphthalen-2-yl) anthracene-9 represented by (1-1-7)”. , 10-diyl) bis (4,1-phenylene) dipyridine "(25.0 g).

The structure of the pyridylphenyl substituted anthracene compound obtained by NMR measurement was confirmed.
¹ H-NMR (CDCl ₃ ): δ = 8.78 (m, 4H), 8.03 (m, 1H), 8.00 (m, 1H), 7.95 (d, 4H), 7.65 -7.90 (m, 16H), 7.37-7.50 (m, 4H).

<Synthesis Example of Compound Represented by Formula (1-1-2)>

<Synthesis of 2-([1,1′-biphenyl] -3-yl) anthracene>
2-bromoanthracene (31.1 g), 3-biphenylboronic acid (18.5 g), bis (dibenzylideneacetone) palladium (0) (0.22 g), tricyclohexylphosphine (0.22 g), tripotassium phosphate (49.5 g), 1,2,4-trimethylbenzene (200 ml), t-butyl alcohol (40 ml) and water (8 ml) were placed in a flask and stirred at reflux temperature for 1.5 hours under a nitrogen atmosphere. After completion of the heating, the reaction solution was cooled to room temperature and suction filtered with a Kiriyama funnel with celite. The obtained filtrate was distilled off under reduced pressure and then washed with heptane to obtain 2-([1,1′-biphenyl] -3-yl) anthracene (32.0 g).

<Synthesis of 2-([1,1′-biphenyl] -3-yl) -9,10-dibromoanthracene>
Bromine (25.0 g) was added dropwise to a flask containing 2-([1,1′-biphenyl] -3-yl) anthracene (32.0 g) and chloroform (300 ml). After completion of the dropwise addition, the mixture was stirred at room temperature overnight, and water, sodium bisulfite and sodium hydrogen carbonate were added to stop the reaction. Chloroform was distilled off from the reaction solution under reduced pressure, followed by filtration. The resulting solid was washed with water, heptane, and then with methanol to give 2-([1,1′-biphenyl] -3-yl)- 9,10-dibromoanthracene (34.0 g) was obtained.

<2,2 ′-(2-([1,1′-biphenyl] -3-yl) anthracene-9,10-diyl) bis (4,4,5,5-tetramethyl-1,3,2- Synthesis of dioxaborolane>
2-([1,1′-biphenyl] -3-yl) -9,10-dibromoanthracene (34.0 g), bispinacolatodiboron (44.2 g), bis (dibenzylideneacetone) palladium (0) (2.0 g), tricyclohexylphosphine (2.0 g), potassium acetate (27.4 g), potassium carbonate (19.2 g) and anisole (360 ml) were heated at 130 ° C. for 2 hours under a nitrogen atmosphere. Stir. After completion of the heating, the reaction solution was cooled to room temperature, and suction filtered using a Kiriyama funnel with celite. Crystals obtained by adding heptane to the filtrate were filtered off and 2,2 ′-(2- [1,1′-biphenyl] -3-yl) anthracene-9,10-diyl) bis (4,4,4). 5,5-tetramethyl-1,3,2-dioxaborolane) (31.0 g) was obtained.

<Synthesis of Compound Represented by Formula (1-1-2)>
2,2 ′-(2- [1,1′-biphenyl] -3-yl) anthracene-9,10-diyl) bis (4,4,5,5-tetramethyl-1,3,2-dioxaborolane) (24.3 g), 4- (4-bromophenyl) pyridine (23.4 g), Pd (PPh ₃ ) ₄ (2.4 g), tripotassium phosphate (35.4 g), 1,2,4-trimethyl Benzene (120 ml), t-butyl alcohol (24 ml) and water (5 ml) were placed in a flask and stirred at reflux temperature for 1 hour under a nitrogen atmosphere. After completion of heating, the reaction solution was cooled to room temperature, and water and heptane were added and filtered. The obtained solid was washed with water and methanol and then recrystallized from nitrobenzene to give the compound “4,4 ′-((2- [1,1′-biphenyl]- 3-yl) anthracene-9,10-diyl) bis (4,1-phenylene) dipyridine "(12.5 g) was obtained.

The structure of the pyridylphenyl substituted anthracene compound obtained by NMR measurement was confirmed.
¹ H-NMR (CDCl ₃ ): δ = 8.76 (m, 4H), 7.98 (m, 1H), 7.93 (m, 4H), 7.86 (d, 1H), 7.77 (M, 3H), 7.65 to 7.73 (m, 9H), 7.52 to 7.58 (m, 4H), 7.47 (t, 1H), 7.34-7.43 (m , 5H).

<Synthesis of Compound Represented by Formula (1-1-3)>

2,2 ′-(2-([1,1′-biphenyl] -4-yl) anthracene-9,10-diyl) bis (4,4,5,5-tetramethyl-1,3,2-dioxaborolane ) (58.2 g), 4- (4-bromophenyl) pyridine (56.2 g), Pd (PPh ₃ ) ₄ (2.31 g), tripotassium phosphate (106.0 g), 1,2,4- Trimethylbenzene (320 ml), t-butyl alcohol (65 ml) and water (65 ml) were placed in a flask and stirred at reflux temperature for 2 hours under a nitrogen atmosphere. After heating, the reaction solution was cooled to room temperature, water was added, and a solid was collected by suction filtration. The obtained solid was washed with methanol and heated orthodichlorobenzene. Further, recrystallization from orthodichlorobenzene gave a compound represented by formula (1-1-3) “4,4 ′-((2-([1,1′-biphenyl] -4-yl) anthracene-9, 10-diyl) bis (4,1-phenylene) dipyridine "(48.0 g) was obtained.

The structure of the pyridylphenyl substituted anthracene compound obtained by NMR measurement was confirmed.
¹ H-NMR (CDCl ₃ ): δ = 8.77 (m, 4H), 7.99 (m, 1H), 7.94 (m, 4H), 7.86 (d, 1H), 7.77 (M, 2H), 7.63-7.74 (m, 13H), 7.60 (m, 2H), 7.38-7.45 (m, 4H), 7.35 (t, 1H).

<Synthesis of Compound Represented by Formula (1-1-4)>

2,2 ′-(2- (naphthalen-1-yl) anthracene-9,10-diyl) bis (4,4,5,5-tetramethyl-1,3,2-dioxaborolane) (54.8 g), 4- (4-Bromophenyl) pyridine (55.3 g), Pd (PPh ₃ ) ₄ (5.69 g), tripotassium phosphate (83.6 g), 1,2,4-trimethylbenzene (300 ml), t -Butyl alcohol (60 ml) and water (12 ml) were placed in a flask and stirred at reflux temperature for 1 hour under a nitrogen atmosphere. After heating, the reaction solution was cooled to room temperature, water was added, and the precipitate was collected by suction filtration. The resulting solid was washed with methanol and then with ethyl acetate. Further, after washing with heated orthodichlorobenzene, the product was purified by activated carbon column chromatography (chlorobenzene), and the compound “4,4 ′-((2-naphthalen-1-yl) represented by the formula (1-1-4)” was obtained. ) Anthracene-9,10-diyl) bis (4,1-phenylene) dipyridine "(8.19 g).

The structure of the pyridylphenyl substituted anthracene compound obtained by NMR measurement was confirmed.
¹ H-NMR (CDCl ₃ ): δ = 8.77 (dd, 2H), 8.70 (dd, 2H), 7.95 (d, 2H), 7.82-7.92 (m, 7H) , 7.75-7.81 (m, 2H), 7.71 (m, 4H), 7.66 (d, 2H), 7.62 (dd, 2H), 7.57 (dd, 1H), 7.39-7.52 (m, 6H).

<Synthesis Example of Compound Represented by Formula (1-2-10)>

<Synthesis of 4- (3-bromophenyl) pyridine>
To a flask containing 4-iodopyridine (6.0 g) and THF (30 ml), 2M isopropylmagnesium chloride THF solution (16.1 ml) was added dropwise with stirring and cooling in an nitrogen atmosphere. After completion of dropping, the mixture was stirred at room temperature for 0.5 hour. The flask was cooled again with ice water and zinc chloride tetramethylethylenediamine complex (8.1 g) was added with stirring. Thereafter, the mixture was stirred at room temperature for 1 hour, 1-bromo-3-iodobenzene (8.2 g) and Pd (PPh ₃ ) ₄ (1.0 g) were added, and the mixture was stirred at reflux temperature for 2 hours. In order to cool the reaction solution to room temperature and remove the metal ions of the catalyst, a solution of ethylenediaminetetraacetic acid / tetrasodium salt dihydrate corresponding to approximately 2 moles of the target compound in an appropriate amount of water ( Hereinafter, abbreviated as EDTA · 4Na aqueous solution). Further, ethyl acetate was added to carry out a liquid separation operation. The organic layer was concentrated with an evaporator and purified by silica gel chromatography (toluene / ethyl acetate = 80/20 (volume ratio)) to obtain 4- (3-bromophenyl) pyridine (6.2 g).

<2,2 ′-(2-([1,1 ′: 3 ′, 1 ″ -terphenyl] -5′-yl) anthracene-9,10-diyl) bis (4,4,5,5-tetra Synthesis of methyl-1,3,2-dioxaborolane)
This boronic ester was synthesized according to Scheme 1-1 to Scheme 1-5 described in JP-A-2009-275013 (see pages 7 to 10 of the publication, paragraphs [0014] to [0017]).

<Synthesis of Compound Represented by Formula (1-2-10)>
2,2 ′-(2-([1,1 ′: 3 ′, 1 ″ -terphenyl] -5′-yl) anthracene-9,10-diyl) bis (4,4,5,5-tetramethyl -1,3,2-dioxaborolane (35.0 g), 4- (3-bromophenyl) pyridine (29.9 g), Pd (PPh ₃ ) ₄ (6.2 g), tripotassium phosphate (45.2 g) ), 1,2,4-trimethylbenzene (175 ml), t-butyl alcohol (35 ml) and water (7 ml) were stirred in a nitrogen atmosphere at reflux temperature for 1 hour. The mixture was cooled to room temperature, and water and toluene were added to carry out a liquid separation operation. , Formula (1-2-10 The compound represented by the formula “4,4 ′-((2- [1,1 ′: 3 ′, 1 ″ -terphenyl] -5′-yl) anthracene-9,10-diyl) bis (3,1- Phenylene) dipyridine "(14.2 g) was obtained.

The structure of the pyridylphenyl substituted anthracene compound obtained by NMR measurement was confirmed.
¹ H-NMR (CDCl ₃ ): δ = 8.68 (m, 4H), 8.14 (m, 1H), 7.82-7.90 (m, 5H), 7.70-7.80 ( m, 8H), 7.58-7.66 (m, 10H), 7.35-7.45 (m, 8H).

<Synthesis Example of Compound Represented by Formula (1-2-7)>

<Synthesis of 2- (naphthalen-1-yl) anthracene>
2-bromoanthracene (10.0 g), 1-naphthaleneboronic acid (12.5 g), Pd (PPh ₃ ) ₄ (1.1 g), sodium carbonate (10.3 g), toluene (100 ml), ethanol (20 ml) And water (20 ml) were placed in a flask and stirred at reflux temperature for 6 hours under a nitrogen atmosphere. After completion of the heating, the reaction solution was cooled to room temperature, and a liquid separation operation was performed. The organic layer was concentrated under reduced pressure and purified by silica gel chromatography (toluene). The solid obtained by concentrating the eluate under reduced pressure was recrystallized from tetrahydrofuran to obtain 2- (naphthalen-1-yl) anthracene (11.6 g).

<Synthesis of 9,10-dibromo-2- (naphthalen-1-yl) anthracene>
A flask containing 2- (naphthalen-2-yl) anthracene (7.0 g), iodine (30 mg) and tetrahydrofuran (120 ml) was cooled in an ice bath and N-bromosuccinimide (9.8 g) was added. After stirring for 1 hour while cooling in an ice bath, the mixture was stirred at room temperature for 3 and a half hours. The solid in the reaction solution was collected by suction filtration and washed with an aqueous sodium thiosulfate solution. This solid was dissolved in chlorobenzene, and saturated saline was added to carry out a liquid separation operation. The organic layer was concentrated under reduced pressure, and the precipitated solid was collected by suction filtration to obtain 9,10-dibromo-2- (naphthalen-1-yl) anthracene (4.4 g).

<Synthesis of 2,2 ′-(2- (naphthalen-1-yl) anthracene-9,10-diyl) bis (4,4,5,5-tetramethyl-1,3,2-dioxaborolane)>
9,10-dibromo-2- (naphthalen-1-yl) anthracene (3.2 g), bispinacolatodiboron (4.4 g), bis (dibenzylideneacetone) palladium (0) (0.2 g), tri A flask containing cyclohexylphosphine (0.2 g), potassium acetate (2.7 g), potassium carbonate (1.9 g) and anisole (15 ml) was heated and stirred at 130 ° C. for 7 hours under a nitrogen atmosphere. After completion of the heating, the reaction solution was cooled to room temperature, and suction filtered using a Kiriyama funnel with celite. Crystals obtained by adding heptane to the filtrate were collected by suction filtration, and 2,2 ′-(2- (naphthalen-1-yl) anthracene-9,10-diyl) bis (4,4,5,5) was collected. -Tetramethyl-1,3,2-dioxaborolane) (3.0 g) was obtained.

<Synthesis of Compound Represented by Formula (1-2-7)>
2,2 ′-(2- (naphthalen-1-yl) anthracene-9,10-diyl) bis (4,4,5,5-tetramethyl-1,3,2-dioxaborolane) (3.0 g), 4- (3-bromophenyl) pyridine (3.2 g), Pd (PPh ₃ ) ₄ (320 mg), tripotassium phosphate (4.8 g), 1,2,4-trimethylbenzene (10 ml), t-butyl Alcohol (2 ml) and water (0.5 ml) were placed in a flask and stirred at reflux temperature for 4 hours under a nitrogen atmosphere. After completion of the heating, the reaction solution was cooled to room temperature, water and toluene were added, and a liquid separation operation was performed. The solvent was distilled off from the organic layer under reduced pressure, and the residue was purified by silica gel column chromatography (toluene / ethyl acetate = 80/20 (volume ratio)) to obtain the compound “4,4 ′ represented by the formula (1-2-7). -((2-Naphthalen-1-yl) anthracene-9,10-diyl) bis (3,1-phenylene) dipyridine "(2.2 g) was obtained.

The structure of the pyridylphenyl substituted anthracene compound obtained by NMR measurement was confirmed.
¹ H-NMR (CDCl ₃ ): δ = 8.69 (dd, 2H), 8.65 (m, 2H), 7.75-7.91 (m, 12H), 7.60-7.70 ( m, 5H), 7.55 (m, 3H), 7.38-7.50 (m, 5H), 7.30 (t, 1H).

<Synthesis Example of Compound Represented by Formula (1-2-1)>

<Synthesis of 2-([1,1′-biphenyl] -4-yl) anthracene>
2-bromoanthracene (100.0 g), [1,1′-biphenyl] -4-ylboronic acid (92.4 g), bis (dibenzylideneacetone) palladium (0) (1.1 g), tricyclohexylphosphine (1 0.1 g), tripotassium phosphate (310.0 g), 1,2,4-trimethylbenzene (1000 ml), t-butyl alcohol (200 ml) and water (40 ml) were placed in a flask and refluxed under a nitrogen atmosphere. For 3 and a half hours. After completion of the heating, the reaction solution was cooled to room temperature, water was added and stirred, and then a solid was collected by suction filtration. The obtained solid was washed with methanol and then with heptane to obtain 2-([1,1′-biphenyl] -4-yl) anthracene (128.0 g).

<Synthesis of 2-([1,1′-biphenyl] -4-yl) -9,10-dibromoanthracene>
Bromine (100.0 g) was added dropwise to a flask containing 2-([1,1′-biphenyl] -4-yl) anthracene (93.6 g) and chloroform (2000 ml) at room temperature under a nitrogen atmosphere. After stirring at room temperature overnight, chlorobenzene (500 ml) was added, and the mixture was stirred at 80 ° C. for 4 hours. After completion of the reaction, an aqueous sodium hydrogen carbonate solution and then an aqueous sodium sulfite solution were added, and a solid was collected by suction filtration. The obtained solid was washed with methanol and then dissolved in heated chlorobenzene, and the insoluble matter was removed by decantation. The solution was cooled to room temperature, and the precipitated crystals were collected by suction filtration to obtain 2-([1,1′-biphenyl] -4-yl) -9,10-dibromoanthracene (126.0 g). .

<2,2 ′-(2-([1,1′-biphenyl] -4-yl) anthracene-9,10-diyl) bis (4,4,5,5-tetramethyl-1,3,2- Synthesis of dioxaborolane>
2-([1,1′-biphenyl] -4-yl) -9,10-dibromoanthracene (62.0 g), bispinacolatodiboron (77.5 g), bis (dibenzylideneacetone) palladium (0) (7.30 g), tricyclohexylphosphine (8.55 g), potassium acetate (49.9 g), potassium carbonate (35.1 g) and anisole (760 ml) were placed in a flask under nitrogen atmosphere at 150 ° C. for 2.5. Stir for hours. After completion of the heating, the reaction solution was cooled to room temperature, xylene (1000 ml) was added, and suction filtration was performed using a Kiriyama funnel with celite. The filtrate was distilled off under reduced pressure, heptane was added, and the resulting crystals were collected by suction filtration, and 2,2 ′-(2-([1,1′-biphenyl] -4-yl) anthracene-9,10. -Diyl) bis (4,4,5,5-tetramethyl-1,3,2-dioxaborolane) (51.8 g) was obtained.

<Synthesis Example of Compound Represented by Formula (1-2-1)>
2,2 ′-(2-([1,1′-biphenyl] -4-yl) anthracene-9,10-diyl) bis (4,4,5,5-tetramethyl-1,3,2-dioxaborolane ) (46.3 g), 4- (3-bromophenyl) pyridine (44.7 g), Pd (PPh ₃ ) ₄ (1.84 g), tripotassium phosphate (84.4 g), 1,2,4- Trimethylbenzene (260 ml), t-butyl alcohol (52 ml) and water (10 ml) were placed in a flask and stirred at reflux temperature for 2 hours under a nitrogen atmosphere. After heating, the reaction solution was cooled to room temperature, water was added, and a solid was collected by suction filtration. The obtained solid was washed with methanol and heated chlorobenzene. Furthermore, after recrystallizing from orthodichlorobenzene, the product was purified by activated carbon column chromatography (chlorobenzene), and the compound “4,4 ′-((2-([1,1 ′ ′) represented by the formula (1-2-1) -Biphenyl] -4-yl) anthracene-9,10-diyl) bis (3,1-phenylene)) dipyridine "(29.6 g).

The structure of the pyridylphenyl substituted anthracene compound obtained by NMR measurement was confirmed.
¹ H-NMR (CDCl ₃ ): δ = 8.69 (m, 4H), 7.98 (m, 1H), 7.89 (d, 2H), 7.84 (m, 3H), 7.69 -7.81 (m, 5H), 7.58-7.67 (m, 12H), 7.32-7.46 (m, 5H).

<Synthesis of Compound Represented by Formula (1-2-2)>

2,2 ′-(2-([1,1′-biphenyl] -3-yl) anthracene-9,10-diyl) bis (4,4,5,5-tetramethyl-1,3,2-dioxaborolane ) (67.6 g), 4- (3-bromophenyl) pyridine (65.2 g), Pd (PPh ₃ ) ₄ (6.7 g), tripotassium phosphate (98.5 g), 1,2,4- Trimethylbenzene (350 ml), t-butyl alcohol (70 ml) and water (14 ml) were placed in a flask and stirred at reflux temperature for 1 hour under a nitrogen atmosphere. After completion of the heating, the reaction solution was cooled to room temperature and suction filtered with a Kiriyama funnel with celite. After the filtrate was distilled off under reduced pressure, methanol was added to precipitate a precipitate. The precipitate collected by suction filtration was washed with heated ethyl acetate and then purified by activated carbon column chromatography (toluene). Further purification was performed by silica gel column chromatography (toluene / ethyl acetate mixed solvent). At this time, referring to the method described in “Chemical Doujin Shuppan Co., Ltd., page 94”, the ratio of ethyl acetate in the developing solution was gradually increased. The target product was eluted by increasing the amount to 1. The solvent was distilled off under reduced pressure, and the compound represented by formula (1-2-2) “4,4 ′-((2-([1,1′-biphenyl] -3-yl) anthracene-9,10- Diyl) bis (3,1-phenylene)) dipyridine "(21.3 g) was obtained.

The structure of the pyridylphenyl substituted anthracene compound obtained by NMR measurement was confirmed.
¹ H-NMR (CDCl ₃ ): δ = 8.68 (m, 4H), 7.99 (m, 1H), 7.82-7.91 (m, 5H), 7.74-7.80 ( m, 5H), 7.70 (dd, 1H), 7.59-7.66 (m, 6H), 7.50-7.57 (m, 4H), 7.47 (t, 1H), 7 .32-7.43 (m, 5H).

<Synthesis of Compound Represented by Formula (1-2-4)>

2,2 ′-(2- (naphthalen-2-yl) anthracene-9,10-diyl) bis (4,4,5,5-tetramethyl-1,3,2-dioxaborolane) (68.1 g), 4- (3-bromophenyl) pyridine (68.8 g), Pd (PPh ₃ ) ₄ (7.05 g), tripotassium phosphate (104 g), 1,2,4-trimethylbenzene (350 ml), t-butanol (70 ml) and water (14 ml) were placed in a flask and stirred at reflux temperature for 1 hour under a nitrogen atmosphere. After completion of heating, the reaction solution was cooled to room temperature, and water and heptane were added and filtered. The resulting solid was washed with water, methanol and then ethyl acetate. Further, after washing with heated chlorobenzene, the compound "4,4 '-((2-naphthalen-2-yl) anthracene-9, represented by the formula (1-2-4)" was recrystallized from orthodichlorobenzene. 10-diyl) bis (3,1-phenylene) dipyridine "(36.2 g) was obtained.

The structure of the pyridylphenyl substituted anthracene compound obtained by NMR measurement was confirmed.
¹ H-NMR (CDCl ₃ ): δ = 8.68 (m, 4H), 8.05 (m, 1H), 8.00 (m, 1H), 7.74-7.92 (m, 13H) , 7.61-7.70 (m, 7H), 7.47 (m, 2H), 7.40 (m, 2H).

  By appropriately changing the raw material compound, another pyridylphenyl-substituted anthracene compound of the present invention can be synthesized by a method according to the synthesis example described above.

  Hereinafter, in order to describe the present invention in more detail, examples of the organic EL device using the compound of the present invention are shown, but the present invention is not limited thereto.

<Examples relating to the compound represented by the general formula (1-1)>
The organic EL elements according to Examples 1 to 5 and Comparative Example 1 were prepared, and the drive start voltage (V) in the constant current drive test and the time (hr) for maintaining the luminance of 90% or more of the initial value were measured. went. Hereinafter, examples and comparative examples will be described in detail.

Table 1 below shows the material configuration of each layer in the produced organic EL elements according to Examples 1 to 5 and Comparative Example 1. In all cases, the cathode was composed of quinolinol lithium (Liq) / (magnesium + silver).

In Table 1, “HI” is N4, N4′-diphenyl-N4, N4′-bis (9-phenyl-9H-carbazol-3-yl)-[1,1′-biphenyl] -4,4′-diamine. , “NPD” is N, N′-diphenyl-N, N′-dinaphthyl-4,4′-diaminobiphenyl, compound (A) is 9-phenyl-10- (4-phenylnaphthalen-1-yl) anthracene, compound (B) is ^{N 5, N 5, N 9} , N 9 -7,7- hexaphenyl -7H- benzo [C] fluorene-5,9-diamine, compound (C) is 4,4 '- (( 2-Phenylanthracene-9,10-diyl) bis (4,1-phenylene)) dipyridine, and “Liq” is 8-quinolinol lithium. The chemical structure is shown below.

<Example 1>
<Element Using Compound (1-1-10) for Electron Transport Layer>
A glass substrate of 26 mm × 28 mm × 0.7 mm (manufactured by Optoscience Co., Ltd.) obtained by polishing ITO deposited to a thickness of 180 nm by sputtering to 150 nm was used as a transparent support substrate. This transparent support substrate is fixed to a substrate holder of a commercially available vapor deposition apparatus (manufactured by Vacuum Kiko Co., Ltd.), and a molybdenum vapor deposition boat containing HI, a molybdenum vapor deposition boat containing NPD, and compound (A) are placed therein. Molybdenum deposition boat, molybdenum deposition boat containing compound (B), molybdenum deposition boat containing compound (1-1-10) of the present invention, molybdenum containing quinolinol lithium (Liq) A vapor deposition boat, a molybdenum boat containing magnesium, and a tungsten vapor deposition boat containing silver were mounted.

The following layers were sequentially formed on the ITO film of the transparent support substrate. The vacuum chamber was depressurized to 5 × 10 ⁻⁴ Pa, and first, a vapor deposition boat containing HI was heated and vapor-deposited to a film thickness of 40 nm to form a hole injection layer, and then NPD entered. The vapor deposition boat was heated and vapor-deposited so that it might become a film thickness of 30 nm, and the positive hole transport layer was formed. Next, the vapor deposition boat containing the compound (A) and the vapor deposition boat containing the compound (B) were heated at the same time to form a light emitting layer by vapor deposition to a film thickness of 35 nm. The deposition rate was adjusted so that the weight ratio of compound (A) to compound (B) was approximately 95 to 5. Next, the evaporation boat containing the compound (1-1-10) was heated and evaporated to a thickness of 15 nm to form an electron transport layer. The deposition rate of each layer was 0.01 to 1 nm / second.

  Thereafter, the vapor deposition boat containing quinolinol lithium (Liq) was heated and vapor-deposited at a vapor deposition rate of 0.01 to 0.1 nm / second so as to have a film thickness of 1 nm. Next, a boat containing magnesium and a boat containing silver were heated at the same time to form a cathode with a thickness of 100 nm. At this time, the deposition rate was adjusted so that the atomic ratio of magnesium and silver was 10: 1, and the cathode was formed so that the deposition rate was 0.1 nm to 10 nm / second, thereby obtaining an organic electroluminescent device.

When a direct current voltage was applied using the ITO electrode as the anode and the magnesium / silver electrode as the cathode, blue light emission with a wavelength of about 460 nm was obtained. In addition, a constant current driving test was performed at a current density for obtaining an initial luminance of 2000 cd / m ² . As a result, the drive test start voltage was 4.89 V, and the time for maintaining the luminance of 90% (1800 cd / m ² ) or more of the initial value was 206 hours.

<Example 2>
<Element Using Compound (1-1-7) for Electron Transport Layer>
An organic EL device was obtained by the method according to Example 1 except that the compound (1-1-10) was changed to the compound (1-1-7). A constant current driving test was carried out using an ITO electrode as an anode and a magnesium / silver electrode as a cathode at a current density for obtaining an initial luminance of 2000 cd / m ² . As a result, the drive test start voltage was 5.31 V, and the time for maintaining the luminance of 90% or more of the initial value was 158 hours.

<Example 3>
<Element Using Compound (1-1-2) for Electron Transport Layer>
An organic EL device was obtained by the method according to Example 1 except that the compound (1-1-10) was changed to the compound (1-1-2). A constant current driving test was carried out using an ITO electrode as an anode and a magnesium / silver electrode as a cathode at a current density for obtaining an initial luminance of 2000 cd / m ² . As a result, the driving test start voltage was 5.24 V, and the time for maintaining the luminance of 90% or more of the initial value was 104 hours.

<Example 4>
<Element Using Compound (1-1-3) for Electron Transport Layer>
An organic EL device was obtained by the method according to Example 1 except that the compound (1-1-10) was changed to the compound (1-1-3). A constant current driving test was carried out using an ITO electrode as an anode and a magnesium / silver electrode as a cathode at a current density for obtaining an initial luminance of 2000 cd / m ² . As a result, the driving test start voltage was 5.26 V, and the time for maintaining the luminance of 90% or more of the initial value was 103 hours.

<Example 5>
<Element Using Compound (1-1-4) for Electron Transport Layer>
An organic EL device was obtained by the method according to Example 1 except that the compound (1-1-10) was changed to the compound (1-1-4). A constant current driving test was carried out using an ITO electrode as an anode and a magnesium / silver electrode as a cathode at a current density for obtaining an initial luminance of 2000 cd / m ² . As a result, the driving test start voltage was 5.48 V, and the time for maintaining the luminance of 90% or more of the initial value was 148 hours.

<Comparative Example 1>
An organic EL device was obtained by the method according to Example 1 except that the compound (1-10) was changed to the compound (C). A constant current driving test was carried out using an ITO electrode as an anode and a magnesium / silver electrode as a cathode at a current density for obtaining an initial luminance of 2000 cd / m ² . As a result, the drive test start voltage was 5.13 V, and the time for maintaining the luminance of 90% or more of the initial value was 66 hours.

The above results are summarized in Table 2.

<Examples relating to the compound represented by the general formula (1-2)>
The organic EL elements according to Examples 6 and 7 and Comparative Example 2 were manufactured, and the measurement of the drive start voltage (V) in the constant current drive test and the time (hr) for maintaining the luminance of 90% or more of the initial value, respectively. went. Hereinafter, examples and comparative examples will be described in detail.

Table 3 below shows the material configuration of each layer in the produced organic EL elements according to Examples 6 and 7 and Comparative Example 2. In all cases, the cathode was composed of quinolinol lithium (Liq) / (magnesium + silver).

In Table 3, “HI” is N ⁴ , N ^{4 ′} -diphenyl-N ⁴ , N ^{4 ′} -bis (9-phenyl-9H-carbazol-3-yl)-[1,1′-biphenyl] -4, 4′-diamine, “NPD” is N ⁴ , N ^{4 ′} -di (naphthalen-1-yl) -N ⁴ , N ^{4 ′} -diphenyl- [1,1′-biphenyl] -4,4′-diamine, compound (A) is 9-phenyl-10- (4-phenyl-1-yl) anthracene, the compound (B) is ^{N 5, N 5, N 9} , N 9 -7,7- hexaphenyl -7H- benzo [C] fluorene-5,9-diamine, compound (D) is 4,4 ′-((2-phenylanthracene-9,10-diyl) bis (3,1-phenylene)) dipyridine, and “Liq” is 8-quinolinol lithium. The chemical structure is shown below.

<Example 6>
<Element Using Compound (1-2-10) for Electron Transport Layer>
A glass substrate of 26 mm × 28 mm × 0.7 mm (manufactured by Optoscience Co., Ltd.) obtained by polishing ITO deposited to a thickness of 180 nm by sputtering to 150 nm was used as a transparent support substrate. This transparent support substrate is fixed to a substrate holder of a commercially available vapor deposition apparatus (manufactured by Vacuum Kiko Co., Ltd.), and a molybdenum vapor deposition boat containing HI, a molybdenum vapor deposition boat containing NPD, and compound (A) are placed therein. Molybdenum vapor deposition boat, molybdenum vapor deposition boat with compound (B), molybdenum vapor deposition boat with compound (1-2-10) of the present invention, molybdenum with quinolinol lithium (Liq) A vapor deposition boat, a molybdenum boat containing magnesium, and a tungsten vapor deposition boat containing silver were mounted.

The following layers were sequentially formed on the ITO film of the transparent support substrate. The vacuum chamber was depressurized to 5 × 10 ⁻⁴ Pa, first, a vapor deposition boat containing HI was heated to deposit to a film thickness of 40 nm to form a hole injection layer, and then NPD entered. The vapor deposition boat was heated and vapor-deposited so that it might become a film thickness of 30 nm, and the positive hole transport layer was formed. Next, the vapor deposition boat containing the compound (A) and the vapor deposition boat containing the compound (B) were heated at the same time to form a light emitting layer by vapor deposition to a film thickness of 35 nm. The deposition rate was adjusted so that the weight ratio of compound (A) to compound (B) was approximately 95 to 5. Next, the evaporation boat containing the compound (1-2-10) was heated and evaporated to a film thickness of 15 nm to form an electron transport layer. The deposition rate of each layer was 0.01 to 1 nm / second.

  Thereafter, the vapor deposition boat containing quinolinol lithium (Liq) was heated and vapor-deposited at a vapor deposition rate of 0.01 to 0.1 nm / second so as to have a film thickness of 1 nm. Next, a boat containing magnesium and a boat containing silver were heated at the same time and evaporated to a film thickness of 100 nm to form a cathode. At this time, the deposition rate was adjusted so that the atomic ratio of magnesium and silver was 10: 1, and the cathode was formed so that the deposition rate was 0.1 to 10 nm / second, to obtain an organic electroluminescent device.

When a direct current voltage was applied using the ITO electrode as the anode and the magnesium / silver electrode as the cathode, blue light emission with a wavelength of about 460 nm was obtained. In addition, a constant current driving test was performed at a current density for obtaining an initial luminance of 2000 cd / m ² . As a result, the driving test start voltage was 5.31 V, and the time for maintaining the luminance of 90% (1800 cd / m ² ) or more of the initial value was 140 hours.

<Example 7>
<Device Using Compound (1-2-2) for Electron Transport Layer>
An organic EL device was obtained by the method according to Example 6 except that the compound (1-2-10) was changed to the compound (1-2-2). A constant current driving test was carried out using an ITO electrode as an anode and a magnesium / silver electrode as a cathode at a current density for obtaining an initial luminance of 2000 cd / m ² . As a result, the driving test start voltage was 5.65 V, and the time for maintaining the luminance of 90% or more of the initial value was 216 hours.

<Comparative example 2>
An organic EL device was obtained by the method according to Example 6 except that the compound (1-2-10) was changed to the compound (D). A constant current driving test was carried out using an ITO electrode as an anode and a magnesium / silver electrode as a cathode at a current density for obtaining an initial luminance of 2000 cd / m ² . As a result, the driving test start voltage was 5.15 V, and the time for maintaining the luminance of 90% or more of the initial value was 68 hours.

The above results are summarized in Table 4.

  According to a preferred aspect of the present invention, it is possible to provide an organic electroluminescent element that improves the lifetime of the light emitting element and has an excellent balance with the driving voltage, a display device including the organic electroluminescent element, and a lighting device including the organic electroluminescent element. it can.

DESCRIPTION OF SYMBOLS 100 Organic electroluminescent element 101 Substrate 102 Anode 103 Hole injection layer 104 Hole transport layer 105 Light emitting layer 106 Electron transport layer 107 Electron injection layer 108 Cathode

Claims (10)

An electron transport material containing a compound represented by the following general formula (1).

In the formula (1), Ar is aryl having 10 to 24 carbon atoms, and the aryl is substituted with alkyl having 1 to 12 carbons, cycloalkyl having 3 to 12 carbons, or aryl having 6 to 20 carbons. The 4-pyridyl group may be linked to the 3- or 4-position of phenyl, and at least one hydrogen in the compound represented by the formula (1) may be substituted with deuterium. The electron transport material containing the compound represented by the following general formula (1-1).

In Formula (1-1), Ar is aryl having 10 to 24 carbon atoms, and the aryl is substituted with alkyl having 1 to 12 carbons, cycloalkyl having 3 to 12 carbons, or aryl having 6 to 20 carbons. In addition, at least one hydrogen in the compound represented by the formula (1-1) may be substituted with deuterium. The electron transport material containing the compound represented by the following general formula (1-2).

In Formula (1-2), Ar is aryl having 10 to 24 carbon atoms, and the aryl is substituted with alkyl having 1 to 12 carbons, cycloalkyl having 3 to 12 carbons, or aryl having 6 to 20 carbons. In addition, at least one hydrogen in the compound represented by the formula (1-2) may be substituted with deuterium.   The electron transport material according to claim 1, wherein Ar is biphenylyl, terphenylyl, or naphthyl, and the naphthyl may be substituted with phenyl.   The electron transport material according to any one of claims 1 to 3, wherein Ar is 3-biphenylyl, 4-biphenylyl, m-terphenyl-5'-yl, 1-naphthyl or 2-naphthyl.   The electron transport material according to claim 1, which is disposed between a pair of electrodes composed of an anode and a cathode, a light emitting layer disposed between the pair of electrodes, and the cathode and the light emitting layer. The organic electroluminescent element which has an electron carrying layer and / or an electron injection layer containing this.   The at least one of the electron transport layer and the electron injection layer further contains at least one selected from the group consisting of a quinolinol-based metal complex, a bipyridine derivative, a phenanthroline derivative, a borane derivative, and a benzimidazole derivative. The organic electroluminescent element described in 1.   At least one of the electron transport layer and the electron injection layer may further include an alkali metal, alkaline earth metal, rare earth metal, alkali metal oxide, alkali metal halide, alkaline earth metal oxide, alkaline earth Containing at least one selected from the group consisting of metal halides, rare earth metal oxides, rare earth metal halides, alkali metal organic complexes, alkaline earth metal organic complexes and rare earth metal organic complexes, The organic electroluminescent element according to claim 6 or 7.   The display apparatus provided with the organic electroluminescent element in any one of Claims 6-8.   The illuminating device provided with the organic electroluminescent element in any one of Claims 6-8.

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