JP5750988B2 - ORGANIC ELECTROLUMINESCENT ELEMENT MATERIAL, ORGANIC ELECTROLUMINESCENT ELEMENT, DISPLAY DEVICE AND LIGHTING DEVICE - Google Patents

Description

  The present invention relates to an organic electroluminescent element material, an organic electroluminescent element, a display device, and a lighting device.

Conventionally, there is an electroluminescence display (ELD) as a light-emitting electronic display device. As a component of ELD, an inorganic electroluminescence element and an organic electroluminescence element (hereinafter also referred to as “organic EL element”) can be given. Inorganic electroluminescent elements have been used as planar light sources, but an alternating high voltage is required to drive the light emitting elements.
On the other hand, an organic EL element has a configuration in which a light emitting layer containing a compound that emits light is sandwiched between a cathode and an anode, and injects electrons and holes into the light emitting layer to recombine excitons. This is an element that emits light by utilizing the emission of light (fluorescence / phosphorescence) when this exciton is deactivated, and can emit light at a voltage of several volts to several tens of volts. Therefore, it has a wide viewing angle, high visibility, and since it is a thin-film type completely solid element, it has attracted attention from the viewpoints of space saving and portability.

For the development of organic EL elements for practical application, M.M. A. Baldo et al. , Nature, 395, 151-154 (1998), since Princeton University reported on an organic EL device using phosphorescence emission from an excited triplet. A. Baldo et al. , Nature, 403, 17, 750-753 (2000), US Pat. No. 6,097,147, research on materials that exhibit phosphorescence at room temperature has become active.
In addition, recently discovered organic EL devices that use phosphorescence can realize a luminous efficiency that is approximately four times that of previous devices that use fluorescence. Research and development of light-emitting element layer configurations and electrodes are performed all over the world. For example, S.M. Lamansky et al. , J .; Am. Chem. Soc. , 123, 4304 (2001), a number of compounds have been studied for synthesis centering on heavy metal complexes such as iridium complexes.
In a light emitting layer of an organic EL element using these phosphorescent light emitting materials, a technique using an organic germanium compound as a host material is disclosed (for example, see Patent Documents 1 to 4). However, there is no description regarding the compound group as in the present invention, and these disclosed materials are still insufficient in terms of the stability of the compound, the light emission lifetime and the like from a practical viewpoint, and further improvement techniques are not available. It was sought after.

International Publication Number WO07 / 111176 A1 International Publication Number WO07 / 142083 A1 International Publication Number WO06 / 173552 A1 International Publication Number WO08 / 153088 A1

  The present invention has been made in view of the above-described problems and circumstances, and the problem to be solved is a material for an organic electroluminescent element and an organic electroluminescent element, particularly a white organic electroluminescent element, which have excellent thermal stability and a long emission lifetime. Is to provide. Moreover, it is providing the display apparatus and illuminating device with which the said organic electroluminescent element was comprised.

一般式（１）
（一般式（１）中、Ａｒ_１及びＡｒ_２は、それぞれ芳香族炭化水素基又は芳香族複素環基を表す。Ｙ_１〜Ｙ₈は、それぞれ窒素原子又はＣＲ₁〜ＣＲ₈を表す。Ｒ₁、Ｒ₂、Ｒ₄、Ｒ₅、Ｒ₇、Ｒ₈は、それぞれ水素原子、アルキル基、芳香族炭化水素基、芳香族複素環基、アミノ基、シリル基、ゲルミル基、又はスタニル基を表す。Ｒ₃ 及びＲ₆はそれぞれ水素原子を表す。Ｘは単結合、-ＣＲ₉Ｒ₁₀-、-ＣＲ₁₁＝ＣＲ₁₂-、-ＳｉＲ₁₃Ｒ₁₄-、-Ｏ-、-ＮＲ₁₅-、-Ｓ-、-ＰＲ₁₆-、-Ｐ（＝Ｏ）Ｒ₁₇-、-ＧｅＲ₁₈Ｒ₁₉-、又は-ＳｎＲ₂₀Ｒ₂₁-を表す。Ｒ₉〜Ｒ₂₁は、それぞれ水素原子、芳香族炭化水素基、又は芳香族複素環基を表す。Ａｒ _１ 、Ａｒ _２ 及びＲ _１ 〜Ｒ _８ のいずれか一つ以上が、カルバゾールを部分構造として有する置換基を表す。） In order to solve the above problems, the invention of claim 1 is a material for an organic electroluminescence element,
It is represented by the following general formula (1).

General formula (1)
(In General Formula (1), Ar ₁ and Ar ₂ each represent an aromatic hydrocarbon group or an aromatic heterocyclic group . Y _{1 to} Y ₈ each represent a nitrogen atom or CR _{1 to} CR ₈ . ₁ , R ₂ , R ₄ , R ₅ , R ₇ , R ₈ are each a hydrogen atom, an alkyl group, an aromatic hydrocarbon group, an aromatic heterocyclic group, an amino group, a silyl group, a germyl group, or a stannyl group. . represents R ₃ and R ₆ .X each represent a hydrogen atom is a single _{bond, -CR 9 R 10 -, -} CR 11 = CR 12 -, - SiR 13 R 14 -, - O -, - NR 15 -, Represents —S—, —PR ₁₆ —, —P (═O) R ₁₇ —, —GeR ₁₈ R ₁₉ —, or —SnR ₂₀ R ₂₁ —, wherein R _{9 to} R ₂₁ represent a hydrogen atom and aromatic carbonization, respectively. hydrogen radical, or an aromatic heterocyclic group. Ar _1, any one or more of Ar ₂ and _R 1 to R ₈ is a substituent having a carbazole as a partial structure It is.)

The invention of claim 2 is the organic electroluminescent element material according to claim 1,
In the general formula (1), X is a single bond.

Invention of Claim 3 in the material for organic electroluminescent elements of Claim 1 or 2,
In the general formula (1), Ar ₁ and Ar ₂ are bonded to each other to form a condensed ring.

The invention of claim 4 is an organic electroluminescence device comprising a plurality of organic functional layers including a light emitting layer containing at least a host compound and a phosphorescent compound between an anode and a cathode,
It contains the organic electroluminescent element material as described in any one of Claims 1-3 as said host compound.

一般式（２）
（一般式（２）中、Ｑ１は、５員又は６員の芳香族環若しくは芳香族複素環を表す。Ａｒ_３は、芳香族炭化水素基又は芳香族複素環基を表す。ｋは、２又は３の整数を示し、イリジウムの価数を満たすようにｍ個の副配位子Ｌを有する。ｍは０又は１を表す。） The invention of claim 5 is the organic electroluminescence device according to claim 4,
At least one of the phosphorescent compounds is an iridium compound represented by the following general formula (2).

General formula (2)
(In General Formula (2), Q1 represents a 5- or 6-membered aromatic ring or aromatic heterocyclic ring. Ar ₃ represents an aromatic hydrocarbon group or an aromatic heterocyclic group. K represents 2 Or, it represents an integer of 3 and has m subligands L so as to satisfy the valence of iridium. M represents 0 or 1.)

The invention of claim 6 provides the organic electroluminescent device according to claim 4 or 5,
The organic electroluminescence element is a white organic electroluminescence element that emits white light.

The invention of claim 7 is a display device,
The organic electroluminescent element as described in any one of Claims 4-6 is comprised.

Invention of Claim 8 is an illuminating device, Comprising:
The organic electroluminescent element as described in any one of Claims 4-6 is comprised.

  ADVANTAGE OF THE INVENTION According to this invention, the organic electroluminescent element material which is excellent in stability and has a long light emission lifetime, an organic electroluminescent element, especially a white organic electroluminescent element can be provided. In addition, a display device and a lighting device including the organic electroluminescence element can be provided.

It is the schematic diagram which showed an example of the display apparatus comprised from an organic EL element. It is a schematic diagram of a display part. It is a schematic diagram of a pixel. It is a schematic diagram of a passive matrix type full color display device. It is the schematic of an illuminating device. It is sectional drawing of an illuminating device.

The organic electroluminescence element material of the present invention (hereinafter referred to as organic EL element material) is represented by the general formula (1). This feature is a technical feature common to the inventions according to claims 1 to 8.
As an embodiment of the present invention, from the viewpoint of manifesting the effects of the present invention, in the general formula (1), X is preferably a single bond, and Ar ₁ and Ar ₂ are bonded to each other to form a condensed ring. It is preferable to form.
In the organic electroluminescence device of the present invention (hereinafter referred to as organic EL device), a plurality of organic compound layers having a light emitting layer containing at least a host compound and a phosphorescent compound are sandwiched between an anode and a cathode. Therefore, it is preferable that the host compound contains an organic EL element material which is a compound represented by the general formula (1). The phosphorescent compound is preferably an iridium compound represented by the general formula (2).
As an embodiment of the present invention, the organic EL element is preferably a white organic EL element that emits white light.
The organic EL element of the present invention can be suitably included in a display device and a lighting device.
Hereinafter, the present invention, its components, and modes and modes for carrying out the present invention will be described in detail. In addition, in this application, "-" is used in the meaning which includes the numerical value described before and behind that as a lower limit and an upper limit.

一般式（１）
（一般式（１）中、Ａｒ_１及びＡｒ_２は、それぞれ芳香族炭化水素基又は芳香族複素環基を表わし、Ｙ_１〜Ｙ₈は、それぞれ窒素原子又はＣＲ₁〜ＣＲ₈を表わす。Ｒ₁、Ｒ₂、Ｒ₄、Ｒ₅、Ｒ₇、Ｒ₈は、それぞれ水素原子、アルキル基、芳香族炭化水素基、芳香族複素環基、アミノ基、シリル基、ゲルミル基、スタニル基を表わし、Ｒ₃、Ｒ₆はそれぞれ水素原子を表わす。Ｘは単結合、-ＣＲ₉Ｒ₁₀-、-ＣＲ₁₁＝ＣＲ₁₂-、-ＳｉＲ₁₃Ｒ₁₄-、-Ｏ-、-ＮＲ₁₅-、-Ｓ-、-ＰＲ₁₆-、-Ｐ（＝Ｏ）Ｒ₁₇-、-ＧｅＲ₁₈Ｒ₁₉-、-ＳｎＲ₂₀Ｒ₂₁-を表わす。Ｒ₉〜Ｒ₂₁は、それぞれ水素原子又は芳香族炭化水素基、芳香族複素環基を表わす。）
本発明に係る一般式（１）で表される化合物は、後述する本発明の有機ＥＬ素子の構成層である有機機能層の少なくとも一層に含有されるが、高い外部取り出し量子効率及び発光寿命の向上の観点からは、発光層に含有されることが好ましく、更に好ましくは該発光層においてホスト化合物として含有されることが好ましい。 [Materials for organic EL elements]
<< Compound Represented by Formula (1) >>
The organic EL device material of the present invention is a compound represented by the following general formula (1).

General formula (1)
(In General Formula (1), Ar ₁ and Ar ₂ each represent an aromatic hydrocarbon group or an aromatic heterocyclic group, and Y _{1 to} Y ₈ each represent a nitrogen atom or CR _{1 to} CR _{8. 1} , R ₂ , R ₄ , R ₅ , R ₇ and R ₈ represent a hydrogen atom, an alkyl group, an aromatic hydrocarbon group, an aromatic heterocyclic group, an amino group, a silyl group, a germyl group, and a stannyl group, respectively. , R ₃ and R ₆ each represent a hydrogen atom, X is a single bond, —CR ₉ R ₁₀ —, —CR ₁₁ ═CR ₁₂ —, —SiR ₁₃ R ₁₄ —, —O—, —NR ₁₅ —, — S—, —PR ₁₆ —, —P (═O) R ₁₇ —, —GeR ₁₈ R ₁₉ —, —SnR ₂₀ R ₂₁ —, wherein R _{9 to} R ₂₁ are each a hydrogen atom or an aromatic hydrocarbon group. Represents an aromatic heterocyclic group.)
The compound represented by the general formula (1) according to the present invention is contained in at least one organic functional layer that is a constituent layer of the organic EL device of the present invention described later, but has high external extraction quantum efficiency and light emission lifetime. From the viewpoint of improvement, it is preferably contained in the light emitting layer, and more preferably contained as a host compound in the light emitting layer.

<< Description of Ar ₁ and Ar ₂ >>
In the general formula (1), examples of the aromatic hydrocarbon group represented by Ar ₁ and Ar ₂ include a phenyl group, a p-chlorophenyl group, a mesityl group, a tolyl group, a xylyl group, a naphthyl group, an anthryl group, an azulenyl group, Examples include acenaphthenyl group, fluorenyl group, phenanthryl group, indenyl group, pyrenyl group, biphenylyl group and the like.
Examples of the aromatic heterocyclic group represented by Ar ₁ and Ar ₂ include pyridyl group, pyridazinyl group, pyrimidinyl group, pyrazinyl group, triazinyl group, triazolyl group, imidazolyl group, pyrazolyl group, thiazolyl group, quinazolinyl group, carbazolyl group, carbolinyl group Group, diazacarbazolyl group, pyrrolidyl group, oxazolidyl group, furyl group, pyrrolyl group, benzoimidazolyl group, oxazolyl group, benzoxazolyl group, isoxazolyl group, isothiazolyl group, furazanyl group, thienyl group, quinolyl group, benzofuryl group , Dibenzofuryl group, benzothienyl group, dibenzothienyl group, indolyl group, quinoxalinyl group, phthalazinyl group and the like.
More preferred aromatic hydrocarbon groups include phenyl group, naphthyl group, fluorenyl group, phenanthryl group, biphenylyl group, fluorenonyl group, and similarly preferred aromatic heterocyclic groups include pyridyl group, pyrimidyl group, imidazolyl group, A pyrazolyl group, a thienyl group, a quinolyl group, a dibenzofuryl group, a carbazolyl group, a carbolinyl group, a diazacarbolinyl group, and more preferably a phenyl group, a naphthyl group, a fluorenyl group, a dibenzofuryl group, a carbazolyl group, and a carbolinyl group Is mentioned.

Ar ₁ and Ar ₂ may be further substituted with a substituent. Examples of such a substituent include an alkyl group (for example, a methyl group, an ethyl group, a propyl group, an isopropyl group, a tert-butyl group, a pentyl group). Hexyl group, octyl group, dodecyl group, tridecyl group, tetradecyl group, pentadecyl group, etc.), cycloalkyl group (eg, cyclopentyl group, cyclohexyl group etc.), alkenyl group (eg, vinyl group, allyl group, 1-propenyl group) , 2-butenyl group, 1,3-butadienyl group, 2-pentenyl group, isopropenyl group, etc.), alkynyl group (for example, ethynyl group, propargyl group, etc.), aromatic hydrocarbon group (aromatic hydrocarbon ring group, Also called aromatic carbocyclic group, allyl group, etc., for example, phenyl group, p-chlorophenyl group, mesityl group, tolyl , Xylyl group, naphthyl group, anthryl group, azulenyl group, acenaphthenyl group, fluorenyl group, phenanthryl group, indenyl group, pyrenyl group, biphenylyl group, etc.), aromatic heterocyclic group (for example, furyl group, thienyl group, pyridyl group, Pyridazinyl group, pyrimidinyl group, pyrazinyl group, triazinyl group, imidazolyl group, pyrazolyl group, thiazolyl group, quinazolinyl group, carbazolyl group, carbolinyl group, diazacarbazolyl group (any carbon atom constituting the carboline ring of the carbolinyl group) One of these is replaced by a nitrogen atom), a phthalazinyl group, etc.), a heterocyclic group (eg, pyrrolidyl group, imidazolidyl group, morpholyl group, oxazolidyl group, etc.), an alkoxy group (eg, methoxy group, ethoxy group, propyl) Oxy group, pentylo Xy group, hexyloxy group, octyloxy group, dodecyloxy group, etc.), cycloalkoxy group (eg, cyclopentyloxy group, cyclohexyloxy group, etc.), aryloxy group (eg, phenoxy group, naphthyloxy group, etc.), alkylthio group (For example, methylthio group, ethylthio group, propylthio group, pentylthio group, hexylthio group, octylthio group, dodecylthio group, etc.), cycloalkylthio group (for example, cyclopentylthio group, cyclohexylthio group, etc.), arylthio group (for example, phenylthio group, Naphthylthio group, etc.), alkoxycarbonyl groups (eg, methyloxycarbonyl group, ethyloxycarbonyl group, butyloxycarbonyl group, octyloxycarbonyl group, dodecyloxycarbonyl group, etc.), aryloxy Rubonyl group (eg, phenyloxycarbonyl group, naphthyloxycarbonyl group, etc.), sulfamoyl group (eg, aminosulfonyl group, methylaminosulfonyl group, dimethylaminosulfonyl group, butylaminosulfonyl group, hexylaminosulfonyl group, cyclohexylaminosulfonyl group) Octylaminosulfonyl group, dodecylaminosulfonyl group, phenylaminosulfonyl group, naphthylaminosulfonyl group, 2-pyridylaminosulfonyl group, etc.), acyl group (for example, acetyl group, ethylcarbonyl group, propylcarbonyl group, pentylcarbonyl group, cyclohexyl) Carbonyl group, octylcarbonyl group, 2-ethylhexylcarbonyl group, dodecylcarbonyl group, phenylcarbonyl group, naphthylcarbonyl group, pyridi Carbonyl group etc.), acyloxy group (eg acetyloxy group, ethylcarbonyloxy group, butylcarbonyloxy group, octylcarbonyloxy group, dodecylcarbonyloxy group, phenylcarbonyloxy group etc.), amide group (eg methylcarbonylamino group) , Ethylcarbonylamino group, dimethylcarbonylamino group, propylcarbonylamino group, pentylcarbonylamino group, cyclohexylcarbonylamino group, 2-ethylhexylcarbonylamino group, octylcarbonylamino group, dodecylcarbonylamino group, phenylcarbonylamino group, naphthylcarbonyl Amino group, etc.), carbamoyl group (for example, aminocarbonyl group, methylaminocarbonyl group, dimethylaminocarbonyl group, propylaminocarbonyl group) Pentylaminocarbonyl group, cyclohexylaminocarbonyl group, octylaminocarbonyl group, 2-ethylhexylaminocarbonyl group, dodecylaminocarbonyl group, phenylaminocarbonyl group, naphthylaminocarbonyl group, 2-pyridylaminocarbonyl group, etc.), ureido group (for example, Methylureido group, ethylureido group, pentylureido group, cyclohexylureido group, octylureido group, dodecylureido group, phenylureido group, naphthylureido group, 2-pyridylaminoureido group, etc.), sulfinyl group (for example, methylsulfinyl group, ethyl) Sulfinyl group, butylsulfinyl group, cyclohexylsulfinyl group, 2-ethylhexylsulfinyl group, dodecylsulfinyl group, phenylsulfinyl group, Phthalylsulfinyl group, 2-pyridylsulfinyl group, etc.), alkylsulfonyl group (for example, methylsulfonyl group, ethylsulfonyl group, butylsulfonyl group, cyclohexylsulfonyl group, 2-ethylhexylsulfonyl group, dodecylsulfonyl group, etc.), arylsulfonyl group Or heteroarylsulfonyl group (for example, phenylsulfonyl group, naphthylsulfonyl group, 2-pyridylsulfonyl group, etc.), amino group (for example, amino group, ethylamino group, dimethylamino group, butylamino group, cyclopentylamino group, 2- Ethylhexylamino group, dodecylamino group, amino group, naphthylamino group, 2-pyridylamino group, diphenylamino group, etc.), halogen atom (for example, fluorine atom, chlorine atom, bromine atom, etc.), fluorinated hydrocarbon group (example) For example, fluoromethyl group, trifluoromethyl group, pentafluoroethyl group, pentafluorophenyl group, etc.), cyano group, nitro group, hydroxy group, mercapto group, silyl group (for example, trimethylsilyl group, triisopropylsilyl group, triphenyl) Silyl group, phenyldiethylsilyl group, etc.), phosphono group and the like. Each substituent may further have a substituent.
Preferred substituents are alkenyl groups, alkynyl groups, aromatic hydrocarbon groups, aromatic heterocyclic groups, and amino groups. More preferred substituents are aromatic hydrocarbon groups, aromatic heterocyclic groups, amino groups. Groups.
When having a plurality of substituents, they may be the same or different, may be further substituted with the above substituents, and the substituents may be linked to each other to form a ring. Good.

In the present invention, Ar ₁ and Ar _{2 in} formula (1) are preferably bonded to each other to form a condensed ring, and particularly preferably Ar ₁ and Ar ₂ are bonded by a single bond to form a condensed ring. This is the case.
Ar ₁ and Ar ₂ are bonded to each other to form a condensed ring, so that the thermal stability of the compound is further improved, and further, T1 (the lowest excited triplet energy level) is made higher than that of the phosphorescent compound. It becomes easy. In addition, Ar ₁ and Ar ₂ are bonded to each other to form a condensed ring, thereby having a spiro structure joined with Ge. This spiro structure also improves the amorphous property of the film after film formation, and more It is considered that it is possible to provide an element having a high light emission lifetime.

Description of «Y ₁ ~Y ₈ »
Y _{1 to} Y ₈ each represent a nitrogen atom or CR _{1 to} CR ₈ (the same number corresponds to the Y suffix and the R suffix. For example, when Y ₅ is a carbon atom, CR ₅ corresponds). , R ₁ , R ₂ , R ₄ , R ₅ , R ₇ and R ₈ are each a hydrogen atom, an alkyl group, an aromatic hydrocarbon group, an aromatic heterocyclic group, an amino group, a silyl group, a germyl group, or a stannyl group. R ₃ and R ₆ each represent a hydrogen atom. R ₁ , R ₂ , R ₄ , R ₅ , R ₇ and R ₈ are preferably a hydrogen atom, an aromatic hydrocarbon group or an aromatic heterocyclic group.
Aromatic hydrocarbon groups include phenyl, p-chlorophenyl, mesityl, tolyl, xylyl, naphthyl, anthryl, azulenyl, acenaphthenyl, fluorenyl, phenanthryl, indenyl, pyrenyl, biphenylyl Groups and the like.
As the aromatic heterocyclic group, pyridyl group, pyridazinyl group, pyrimidinyl group, pyrazinyl group, triazinyl group, triazolyl group, imidazolyl group, pyrazolyl group, thiazolyl group, quinazolinyl group, carbazolyl group, carbolinyl group, diazacarbazolyl group , Pyrrolidyl group, oxazolidyl group, furyl group, pyrrolyl group, benzimidazolyl group, oxazolyl group, benzoxazolyl group, isoxazolyl group, isothiazolyl group, furazanyl group, thienyl group, quinolyl group, benzofuryl group, dibenzofuryl group, benzothienyl group , Dibenzothienyl group, indolyl group, quinoxalinyl group, phthalazinyl group, etc., but preferred aromatic hydrocarbon groups include phenyl group, naphthyl group, fluorenyl group, phenanthryl group, biphenylyl group, fluorinyl group. Nonyl groups can be mentioned, and similarly preferred aromatic heterocyclic groups include pyridyl group, pyrimidyl group, imidazolyl group, pyrazolyl group, thienyl group, quinolyl group, dibenzofuryl group, carbazolyl group, carbolinyl group, diazacarbolinyl Group, more preferably phenyl group, naphthyl group, fluorenyl group, dibenzofuryl group, carbazolyl group, carbolinyl group.

By making Y ₃ and Y ₆ a nitrogen atom or CH (R ₃ and R ₆ are each a hydrogen atom), that is, to the condensed ring Ge bonded through X in the general formula (1) By replacing the p-position without substitution, the amorphousness of the film after film formation is maintained, but the crystallinity as a compound is improved and a high-purity compound can be isolated. Therefore, it is represented by the general formula (1). The organic EL device of the present invention containing the above compound is expected to have a long lifetime.

≪Explanation of X≫
X is a single _{bond, -CR 9 R 10 -, -} CR 11 = CR 12 -, - SiR 13 R 14 -, - O -, - NR 15 -, - S -, - PR 16 -, - P (= O _{) R 17 -, - GeR 18} R 19 -, - SnR 20 R 21 - represents preferably a single _{bond, -CR 9 R 10 -, -} CR 11 = CR 12 -, - SiR 13 R 14 - and is, More preferably, it is a single bond.
In the present invention, since the general formula (1) has a condensed ring structure via X, the stability as a compound is improved, and T1 (the lowest excited triplet energy level) is changed to a phosphorescent compound. On the other hand, it is considered that it is easy to adjust the height appropriately. In particular, when X is a single bond, the thermal stability as a compound is more excellent.
R _{9 to} R ₂₁ are hydrogen atoms or substituents, and examples of such substituents include substituents that may be further substituted with Ar ₁ and Ar ₂ described above. Preferred substituents are an aromatic hydrocarbon group and an aromatic heterocyclic group. R ₉ and R ₁₀ , R ₁₁ and R ₁₂ , R ₁₃ and R ₁₄ , R ₁₈ and R ₁₉ , R ₂₀ and R ₂₁ may be connected to each other to form a ring.

Although the specific example of a compound represented by the said General formula (1) below is shown, the compound in this invention is not limited to these.

窒素雰囲気下、2,2‘-ジヨード-4-ブロモビフェニル 4.85ｇを50mlのテトラヒドロフランに溶解し-78℃に冷却した溶液に、n-ブチルリチウムヘキサン溶液（1.6M） 7.5mlを滴下した後、-78℃で１時間撹拌した。この溶液を、-78℃に冷却した四塩化ゲルマニウム 2.14ｇのテトラヒドロフラン溶液 50ml中に滴下し、滴下後室温まで昇温し、約４時間撹拌した。この反応溶液を減圧蒸留し、3-ブロモ-5,5-ジクロロジベンゾゲルモールを2.29ｇ（61％）得た。
窒素雰囲気下、-78℃にてフェニルリチウムブチルエーテル溶液（1.6M） 4.6mlを、上記で得られたジクロロゲルモール2.29ｇ中に滴下し、滴下後室温まで昇温し、約２時間撹拌した。この反応液に水 100mlを加え、酢酸エチルで抽出し濃縮した後、シリカゲルカラムクロマトグラフィーで精製することで3-ブロモ-5,5-ジフェニルジベンゾゲルモールを2.18ｇ（78％）得た。
窒素雰囲気下、上記で得られた3-ブロモ-5,5-ジフェニルジベンゾゲルモール 2.18ｇ、及び、カルバゾール 0.89ｇ、酸化銅 0.10ｇ、ジピバロイルメタン 0.27ｇ、リン酸三カリウム 1.82ｇをジメチルスルホキシド 50ml中に加え、160℃で８時間加熱した。この反応液に水50mlを加え、濾過した後、シリカゲルカラムクロマトグラフィーで精製することで例示化合物G-１を1.45ｇ（56％）得た。 Although the synthesis example of compound G-1 and G-4 represented by the said General formula (1) below is shown, the other compound of this invention is compoundable by the same method.
<Synthesis example>
Synthesis Example 1 Synthesis of Exemplary Compound G-1

In a nitrogen atmosphere, 7.5 ml of n-butyllithium hexane solution (1.6 M) was added dropwise to a solution obtained by dissolving 4.85 g of 2,2′-diiodo-4-bromobiphenyl in 50 ml of tetrahydrofuran and cooling to −78 ° C. Stir at -78 ° C for 1 hour. This solution was added dropwise to 50 ml of a tetrahydrofuran solution of 2.14 g of germanium tetrachloride cooled to −78 ° C. After the dropwise addition, the mixture was warmed to room temperature and stirred for about 4 hours. This reaction solution was distilled under reduced pressure to obtain 2.29 g (61%) of 3-bromo-5,5-dichlorodibenzogermol.
Under a nitrogen atmosphere, 4.6 ml of a phenyl lithium butyl ether solution (1.6M) was added dropwise at -78 ° C. into 2.29 g of the dichlorogermole obtained above. After the dropwise addition, the temperature was raised to room temperature and stirred for about 2 hours. 100 ml of water was added to the reaction solution, extracted with ethyl acetate, concentrated and purified by silica gel column chromatography to obtain 2.18 g (78%) of 3-bromo-5,5-diphenyldibenzogermol.
Under a nitrogen atmosphere, 2.18 g of 3-bromo-5,5-diphenyldibenzogermol obtained above, 0.89 g of carbazole, 0.10 g of copper oxide, 0.27 g of dipivaloylmethane, and 1.82 g of tripotassium phosphate. Dimethyl sulfoxide was added to 50 ml and heated at 160 ° C. for 8 hours. 50 ml of water was added to the reaction solution, filtered, and purified by silica gel column chromatography to obtain 1.45 g (56%) of Exemplary Compound G-1.

窒素雰囲気下、2,2‘-ジブロモビフェニル 3.12ｇを50mlのテトラヒドロフランに溶解し-78℃に冷却した溶液に、n-ブチルリチウムヘキサン溶液（1.6M） 7.5mlを滴下した後、-78℃で１時間撹拌した。この溶液を、-78℃に冷却した四塩化ゲルマニウム 2.14ｇのテトラヒドロフラン溶液 50ml中に滴下し、滴下後室温まで昇温し、約４時間撹拌した。この反応溶液を減圧蒸留し、5,5-ジクロロジベンゾゲルモールを2.25ｇ（76％）得た。
窒素雰囲気下、Ｎ-（3-ブロモフェニル）カルバゾール 4.89ｇを100mlのジエチルエーテルに溶解し-78℃に冷却した溶液に、n-ブチルリチウムヘキサン溶液（1.6M） 11.4mlを滴下した後、-78℃で１時間撹拌した。この溶液を-78℃で、上記で得られた5,5-ジクロロジベンゾゲルモール 2.25ｇ中に滴下し、滴下後室温まで昇温し、約２時間撹拌した。この反応液に水 100mlを加え、酢酸エチルで抽出し濃縮した後、シリカゲルカラムクロマトグラフィーで精製することで例示化合物G-４を2.80ｇ（52％）得た。 Synthesis Example 2 Synthesis of Exemplary Compound G-4

In a nitrogen atmosphere, 7.5 ml of n-butyllithium hexane solution (1.6M) was added dropwise to a solution obtained by dissolving 3.12 g of 2,2'-dibromobiphenyl in 50 ml of tetrahydrofuran and cooling to -78 ° C. Stir for 1 hour. This solution was added dropwise to 50 ml of a tetrahydrofuran solution of 2.14 g of germanium tetrachloride cooled to −78 ° C. After the dropwise addition, the mixture was warmed to room temperature and stirred for about 4 hours. This reaction solution was distilled under reduced pressure to obtain 2.25 g (76%) of 5,5-dichlorodibenzogermol.
In a nitrogen atmosphere, 11.4 ml of n-butyllithium hexane solution (1.6M) was added dropwise to a solution obtained by dissolving 4.89 g of N- (3-bromophenyl) carbazole in 100 ml of diethyl ether and cooling to -78 ° C. Stir at 78 ° C. for 1 hour. This solution was added dropwise at −78 ° C. to 2.25 g of the 5,5-dichlorodibenzogermol obtained above, and after the addition, the temperature was raised to room temperature and stirred for about 2 hours. To this reaction solution was added 100 ml of water, extracted with ethyl acetate, concentrated, and purified by silica gel column chromatography to obtain 2.80 g (52%) of Exemplified Compound G-4.

[Organic EL device]
Next, details of each component of the organic EL element of the present invention will be sequentially described.
<< Layer structure of organic EL element >>
Although the preferable specific example of the layer structure of the organic EL element of this invention is shown below, this invention is not limited to these.
(I) Anode / light emitting layer unit / electron transport layer / cathode (ii) Anode / hole transport layer / light emitting layer unit / electron transport layer / cathode (iii) Anode / hole transport layer / light emitting layer unit / hole blocking Layer / electron transport layer / cathode (iv) anode / hole transport layer / light emitting layer unit / hole blocking layer / electron transport layer / cathode buffer layer / cathode (v) anode / anode buffer layer / hole transport layer / light emission Layer unit / hole blocking layer / electron transport layer / cathode buffer layer / cathode The layer excluding the anode and cathode in the present invention is the organic functional layer referred to in the present invention.
In the organic EL element of the present invention, the light emitting layer unit may have any number of layers as long as it has at least one light emitting layer, but preferably comprises only one light emitting layer.

<Light emitting layer>
The light emitting layer according to the present invention is a layer that emits light by recombination of electrons and holes injected from the electrode, the electron transport layer, or the hole transport layer, and the light emitting portion is in the layer of the light emitting layer. May be the interface between the light emitting layer and the adjacent layer.
The thickness of the light emitting layer is not particularly limited, but from the viewpoint of improving the uniformity of the film to be formed, preventing the application of unnecessary high voltage during light emission, and improving the stability of the emitted color against the drive current. It is preferable to adjust to the range of 2-200 nm, More preferably, it adjusts to the range of 5-100 nm.
The light emitting layer of the organic EL device of the present invention preferably contains at least one kind of a light emitting host compound and a light emitting dopant as a guest material, and more preferably contains a light emitting host compound and three or more kinds of light emitting dopants.
Hereinafter, a host compound (also referred to as “light-emitting host” or the like) and a light-emitting dopant (also referred to as “light-emitting dopant compound”) included in the light-emitting layer will be described.

(Host compound)
In the present application, the “host compound” means that the compound contained in the light emitting layer has a mass ratio of 20% or more in the layer, and the phosphorescence quantum yield of phosphorescence emission at room temperature (25 ° C.) It is defined as a compound of less than 0.1. The phosphorescence quantum yield is preferably less than 0.01. Moreover, it is preferable that the mass ratio in the layer is 20% or more among the compounds contained in a light emitting layer.
As the host compound, the organic EL device material of the present invention represented by the above general formula (1) can be used, and specific examples include the compounds of G-1 to G-36. Moreover, the organic EL element material of this invention may be used independently, and multiple types of well-known host compounds may be used together. By using a plurality of types of host compounds, it is possible to adjust the movement of charges, and the organic EL element can be made highly efficient. Moreover, it becomes possible to mix different light emission by using multiple types of light emission dopants mentioned later, and, thereby, arbitrary luminescent colors can be obtained.
As the known host compound that may be used in combination, a compound that has a hole transporting ability and an electron transporting ability, prevents the emission of light from becoming longer, and has a high Tg (glass transition temperature) is preferable.
Specific examples of known host compounds include compounds described in the following documents.
JP-A-2001-257076, 2002-308855, 2001-313179, 2002-319491, 2001-357777, 2002-334786, 2002-8860, 2002-334787, 2002-15871, 2002-334788, 2002-43056, 2002-334789, 2002-75645, 2002-338579, 2002-105445 gazette, 2002-343568 gazette, 2002-141173 gazette, 2002-352957 gazette, 2002-203683 gazette, 2002-363227 gazette, 2002-231453 gazette, No. 003-3165, No. 2002-234888, No. 2003-27048, No. 2002-255934, No. 2002-286061, No. 2002-280183, No. 2002-299060, No. 2002. -302516, 2002-305083, 2002-305084, 2002-308837, and the like.
Hereinafter, specific examples of compounds preferably used other than G-1 to G-36 described above are given as host compounds of the light emitting layer of the organic EL device of the present invention, but the present invention is not limited thereto.

(Luminescent dopant)
Examples of the luminescent dopant according to the present invention include a fluorescent luminescent dopant (also referred to as a “fluorescent compound”), a phosphorescent luminescent dopant (“phosphorescent emitter”, “phosphorescent compound”, “phosphorescent luminescent property”). From the viewpoint of obtaining an organic EL device with higher luminous efficiency, a luminescent dopant (simply used in the light-emitting layer or the light-emitting unit of the white organic EL device of the present invention (simply referred to as “compound”)) can be used. , "Light emitting material"), it is preferable to contain a phosphorescent dopant simultaneously with the host compound.

(Phosphorescent dopant)
The phosphorescent dopant according to the present invention is a compound in which light emission from an excited triplet is observed. Specifically, it is a compound that emits phosphorescence at room temperature (25 ° C.) and has a phosphorescence quantum yield. The phosphorescence quantum yield is preferably 0.1 or more, although it is defined as a compound of 0.01 or more at 25 ° C.
The phosphorescence quantum yield can be measured by the method described in Spectroscopic II, page 398 (1992 edition, Maruzen) of Experimental Chemistry Course 4 of the 4th edition. Although the phosphorescence quantum yield in a solution can be measured using various solvents, the phosphorescence emitting dopant according to the present invention achieves the above phosphorescence quantum yield (0.01 or more) in any solvent. It only has to be done.
There are two types of light emission of phosphorescent dopants in principle. One is the recombination of carriers on the host compound to which carriers are transported to generate an excited state of the host compound, and this energy is transferred to the phosphorescent dopant. Energy transfer type to obtain light emission from the phosphorescent dopant, and the other is that the phosphorescent dopant becomes a carrier trap, carrier recombination occurs on the phosphorescent dopant, and the phosphorescent dopant In any case, the excited state energy of the phosphorescent dopant is required to be lower than the excited state energy of the host compound.
The phosphorescent dopant can be appropriately selected from known materials used for the light emitting layer of the organic EL device.

一般式（２）
（一般式（２）中、Ｑ１は、５員又は６員の芳香族環若しくは芳香族複素環を表す。Ａｒ３は、芳香族炭化水素基又は芳香族複素環基を表す。ｋは、２又は３の整数を示し、イリジウムの価数を満たすようにｍ個の副配位子Ｌを有する。ｍは０又は１を表す。）
好ましいイリジウム化合物の具体例については後述する。 The phosphorescent dopant according to the present invention is preferably a complex compound containing a group 8-10 metal in the periodic table of elements, more preferably an iridium compound, an osmium compound, or a platinum compound (platinum complex system). Compound) and rare earth complexes, and most preferred is an iridium compound.
The iridium compound as the phosphorescent compound is preferably an iridium compound represented by the following general formula (2).

General formula (2)
(In General Formula (2), Q1 represents a 5-membered or 6-membered aromatic ring or aromatic heterocyclic ring. Ar3 represents an aromatic hydrocarbon group or an aromatic heterocyclic group. K represents 2 or 3 represents an integer of 3 and has m secondary ligands L so as to satisfy the valence of iridium. M represents 0 or 1.)
Specific examples of preferable iridium compounds will be described later.

(Fluorescent dopant)
Fluorescent light emitting dopants (also referred to as “fluorescent compounds”) include coumarin dyes, pyran dyes, cyanine dyes, croconium dyes, squalium dyes, oxobenzanthracene dyes, fluorescein dyes, rhodamine dyes. And pyrylium dyes, perylene dyes, stilbene dyes, polythiophene dyes, and rare earth complex phosphors.

Hereinafter, although the specific example of the light emission dopant which may be used for formation of the light emitting layer of the organic EL element of this invention is given, this invention is not limited to these.

Next, a charge injection layer, a blocking layer, an electron transport layer, and the like used as a constituent layer of the organic EL element according to the present invention will be described.
<< Charge injection layer: electron injection layer, hole injection layer >>
The charge injection layer according to the present invention is provided as necessary, and includes an electron injection layer and a hole injection layer, and as described above, between the anode and the light emitting layer or the hole transport layer, and the cathode and the light emitting layer or the electron transport layer. May exist between the two.
The “injection layer” is a layer provided between the electrode and the organic functional layer for lowering the driving voltage and improving the light emission luminance. “The organic EL element and its industrialization front line (November 30, 1998, NT. 2) Chapter 2 “Electrode Materials” (pages 123 to 166) of the 2nd volume of “S. Co., Ltd.”. The hole injection layer (anode buffer layer) and the electron injection layer (cathode buffer layer) are is there.
The details of the anode buffer layer (hole injection layer) are described in JP-A-9-45479, JP-A-9-260062, JP-A-8-288069 and the like. As a specific example, copper phthalocyanine is used. Examples thereof include a phthalocyanine buffer layer represented by an oxide, an oxide buffer layer represented by vanadium oxide, an amorphous carbon buffer layer, and a polymer buffer layer using a conductive polymer such as polyaniline (emeraldine) or polythiophene.
The details of the cathode buffer layer (electron injection layer) are described in JP-A-6-325871, JP-A-9-17574, JP-A-10-74586, and the like. Specifically, strontium, aluminum, etc. Metal buffer layer typified by lithium, alkali metal compound buffer layer typified by lithium fluoride, alkaline earth metal compound buffer layer typified by magnesium fluoride, oxide buffer layer typified by aluminum oxide, etc. . The buffer layer (injection layer) is preferably a very thin film, and the film thickness is preferably in the range of 0.1 nm to 5 μm although it depends on the material.

<Blocking layer: hole blocking layer, electron blocking layer>
The “blocking layer” is provided as necessary in addition to the basic constituent layer of the organic compound thin film as described above. For example, it is described in JP-A Nos. 11-204258, 11-204359, and “Organic EL elements and their forefront of industrialization” (issued by NTT, Inc. on November 30, 1998). There is a hole blocking (hole blocking) layer.

“Hole blocking layer” has a function of an electron transport layer in a broad sense, and is made of a hole blocking material having a function of transporting electrons while having a remarkably small ability to transport holes, and transports electrons. While blocking holes, the recombination probability of electrons and holes can be improved.
Moreover, the structure of the electron carrying layer mentioned later can be used as a hole-blocking layer concerning this invention as needed.
The hole blocking layer of the organic EL device according to the present invention is preferably provided adjacent to the light emitting layer.
The hole blocking layer preferably contains the azacarbazole derivative mentioned as the host compound.

In the present invention, when a plurality of light emitting layers having different light emission colors are provided, the light emitting layer having the shortest wavelength of light emission is preferably closest to the anode among all the light emitting layers. In this case, it is preferable to additionally provide a hole blocking layer between the shortest wave layer and the light emitting layer next to the anode next to the shortest wave layer.
Furthermore, it is preferable that 50% by mass or more of the compound contained in the hole blocking layer provided at the position has an ionization potential of 0.3 eV or more higher than the host compound of the shortest wave emitting layer.

The ionization potential is defined by the energy required to emit an electron at the HOMO (highest occupied molecular orbital) level of the compound to the vacuum level, and can be obtained by the following method, for example.
(1) Using Gaussian 98 (Gaussian 98, Revision A.11.4, MJ Frisch, et al, Gaussian, Inc., Pittsburgh PA, 2002.), a molecular orbital calculation software manufactured by Gaussian, USA The ionization potential can be obtained as a value obtained by rounding off the second decimal place of the value (eV unit converted value) calculated by performing structural optimization using B3LYP / 6-31G *. This calculation value is effective because the correlation between the calculation value obtained by this method and the experimental value is high.
(2) The ionization potential can also be obtained by a method of directly measuring by photoelectron spectroscopy. For example, a method known as ultraviolet photoelectron spectroscopy can be suitably used by using a low energy electron spectrometer “Model AC-1” manufactured by Riken Keiki Co., Ltd.

  On the other hand, the “electron blocking layer” has a function of a hole transport layer in a broad sense, and is made of a material that has a function of transporting holes and has an extremely small ability to transport electrons, and transports holes. However, the probability of recombination of electrons and holes can be improved by blocking electrons. Moreover, the structure of the positive hole transport layer mentioned later can be used as an electron blocking layer as needed. The film thickness of the hole blocking layer and the electron transporting layer according to the present invention is preferably 3 to 100 nm, and more preferably 5 to 30 nm.

<< Charge transport layer: electron transport layer, hole transport layer >>
Examples of the charge transport layer according to the present invention include an electron transport layer and a hole transport layer. Hereinafter, the electron transport layer and the hole transport layer according to the present invention will be described in detail.

《Hole transport layer》
The “hole transport layer” is made of a hole transport material having a function of transporting holes, and in a broad sense, a hole injection layer and an electron blocking layer are also included in the hole transport layer. The hole transport layer can be provided as a single layer or a plurality of layers.
The hole transport material has any of hole injection or transport and electron barrier properties, and may be either organic or inorganic. For example, triazole derivatives, oxadiazole derivatives, imidazole derivatives, polyarylalkane derivatives, pyrazoline derivatives and pyrazolone derivatives, phenylenediamine derivatives, arylamine derivatives, amino-substituted chalcone derivatives, oxazole derivatives, styrylanthracene derivatives, fluorenone derivatives, hydrazone derivatives, Examples thereof include stilbene derivatives, silazane derivatives, aniline copolymers, and conductive polymer oligomers, particularly thiophene oligomers.
The above-mentioned materials can be used as the hole transport material, but it is preferable to use a porphyrin compound, an aromatic tertiary amine compound and a styrylamine compound, particularly an aromatic tertiary amine compound.

Representative examples of aromatic tertiary amine compounds and styrylamine compounds include N, N, N ', N'-tetraphenyl-4,4'-diaminophenyl; N, N'-diphenyl-N, N'- Bis (3-methylphenyl)-[1,1′-biphenyl] -4,4′-diamine (TPD); 2,2-bis (4-di-p-tolylaminophenyl) propane; 1,1-bis (4-di-p-tolylaminophenyl) cyclohexane; N, N, N ′, N′-tetra-p-tolyl-4,4′-diaminobiphenyl; 1,1-bis (4-di-p-tolyl) Aminophenyl) -4-phenylcyclohexane; bis (4-dimethylamino-2-methylphenyl) phenylmethane; bis (4-di-p-tolylaminophenyl) phenylmethane; N, N'-diphenyl-N, N ' − (4-methoxyphenyl) -4,4'-diaminobiphenyl; N, N, N ', N'-tetraphenyl-4,4'-diaminodiphenyl ether; 4,4'-bis (diphenylamino) quadriphenyl; N, N, N-tri (p-tolyl) amine; 4- (di-p-tolylamino) -4 '-[4- (di-p-tolylamino) styryl] stilbene; 4-N, N-diphenylamino- (2-diphenylvinyl) benzene; 3-methoxy-4′-N, N-diphenylaminostilbenzene; N-phenylcarbazole, and also two of those described in US Pat. No. 5,061,569. Having a condensed aromatic ring in the molecule, for example, 4,4'-bis [N- (1-naphthyl) -N-phenylamino] biphenyl (NPD), JP-A-4-3086 4,4 ', 4 "-tris [N- (3-methylphenyl) -N-phenylamino] triphenylamine in which three triphenylamine units described in Japanese Patent No. 8 are linked in a starburst type ( MTDATA) and the like.
Furthermore, a polymer material in which these materials are introduced into a polymer chain or these materials are used as a polymer main chain can also be used. In addition, inorganic compounds such as p-type-Si and p-type-SiC can also be used as the hole injection material and the hole transport material.

JP-A-11-251067, J. Org. Huang et. al. A so-called p-type hole transport material as described in a book (Applied Physics Letters 80 (2002), p. 139) can also be used. In the present invention, these materials are preferably used because a light-emitting element with higher efficiency can be obtained.
The hole transport layer can be formed by thinning the hole transport material by a known method such as a vacuum deposition method, a spin coating method, a casting method, a printing method including an ink jet method, or an LB method. it can. About the film thickness of a positive hole transport layer, it is preferable that it is the range of 5 nm-5 micrometers, More preferably, it is 5-200 nm. The hole transport layer may have a single layer structure composed of one or more of the above materials.
Alternatively, a hole transport layer having a high p property doped with impurities can be used. Examples thereof include JP-A-4-297076, JP-A-2000-196140, 2001-102175, J. Pat. Appl. Phys. 95, 5773 (2004), and the like.
In the present invention, it is preferable to use a hole transport layer having such a high p property because a device with lower power consumption can be produced.

Hereinafter, although the specific example of the compound preferably used for formation of the positive hole transport layer of the organic EL element of this invention is given, this invention is not limited to these.

《Electron transport layer》
The “electron transport layer” is made of a material having a function of transporting electrons, and in a broad sense, an electron injection layer and a hole blocking layer are also included in the electron transport layer. The electron transport layer can be provided as a single layer or a plurality of layers.
Conventionally, when a single electron transport layer and a plurality of layers are used, an electron transport material (also serving as a hole blocking material) used for an electron transport layer adjacent to the cathode side with respect to the light emitting layer is injected from the cathode. As long as it has a function of transmitting the generated electrons to the light-emitting layer, any material selected from conventionally known compounds can be selected and used. For example, nitro-substituted fluorene derivatives, diphenylquinone Derivatives, thiopyran dioxide derivatives, carbodiimides, fluorenylidenemethane derivatives, anthraquinodimethane and anthrone derivatives, oxadiazole derivatives, and the like.

In the oxadiazole derivative, a thiadiazole derivative in which the oxygen atom of the oxadiazole ring is substituted with a sulfur atom, and a quinoxaline derivative having a quinoxaline ring known as an electron-withdrawing group can also be used as an electron transport material.
Furthermore, a polymer material in which these materials are introduced into a polymer chain or these materials are used as a polymer main chain can also be used.
In addition, metal complexes of 8-quinolinol derivatives such as tris (8-quinolinol) aluminum (Alq), tris (5,7-dichloro-8-quinolinol) aluminum, tris (5,7-dibromo-8-quinolinol) aluminum. Tris (2-methyl-8-quinolinol) aluminum, tris (5-methyl-8-quinolinol) aluminum, bis (8-quinolinol) zinc (Znq), and the like, and the central metals of these metal complexes are In, Mg, Metal complexes replaced with Cu, Ca, Sn, Ga, or Pb can also be used as the electron transport material.
In addition, metal-free or metal phthalocyanine, or those having terminal ends substituted with an alkyl group or a sulfonic acid group can be preferably used as the electron transporting material.
In addition, the distyrylpyrazine derivative exemplified as the material of the light emitting layer can also be used as an electron transport material, and an inorganic semiconductor such as n-type-Si, n-type-SiC, etc. as in the case of the hole injection layer and the hole transport layer. Can also be used as an electron transporting material.

The electron transport layer can be formed by thinning the electron transport material by a known method such as a vacuum deposition method, a spin coating method, a casting method, a printing method including an ink jet method, or an LB method. .
Although there is no restriction | limiting in particular about the film thickness of an electron carrying layer, Usually, 5 nm-about 5 micrometers, Preferably it is 5 nm-200 nm. The electron transport layer may have a single layer structure composed of one or more of the above materials.
Alternatively, an electron transport layer with high n property doped with impurities as a guest material can be used. Examples thereof include JP-A-4-297076, JP-A-10-270172, JP-A-2000-196140, 2001-102175, J.A. Appl. Phys. 95, 5773 (2004), and the like.
In the present invention, it is preferable to use an electron transport layer having such a high n property because an element with lower power consumption can be manufactured.

Hereinafter, although the specific example of the compound (electron transport material) preferably used together for formation of the electron carrying layer of the white organic EL element of this invention is given, this invention is not limited to these.

"anode"
As the anode in the organic EL element, an electrode material made of a metal, an alloy, an electrically conductive compound, or a mixture thereof having a high work function (4 eV or more) is preferably used. Specific examples of such an electrode substance include metals such as Au, and conductive transparent materials such as CuI, indium tin oxide (ITO), SnO2, and ZnO. Alternatively, an amorphous material such as IDIXO (In2O3-ZnO) that can form a transparent conductive film may be used.
For the anode, a thin film may be formed by depositing these electrode materials by a method such as vapor deposition or sputtering, and a pattern having a desired shape may be formed by photolithography, or when the pattern accuracy is not so high (about 100 μm or more) ), A pattern may be formed through a mask having a desired shape when the electrode material is deposited or sputtered.
Or when using the substance which can be apply | coated like an organic electroconductivity compound, wet film-forming methods, such as a printing system and a coating system, can also be used. When light emission is extracted from the anode, it is desirable that the transmittance be greater than 10%, and the sheet resistance as the anode is preferably several hundred Ω / □ or less.
Further, the film thickness is preferably in the range of 10 to 1000 nm, more preferably in the range of 10 to 200 nm, although it depends on the material.

"cathode"
As the cathode, a material having a work function (4 eV or less) metal (referred to as an electron injecting metal), an alloy, an electrically conductive compound, and a mixture thereof as an electrode material is used. Specific examples of such electrode materials include sodium, sodium-potassium alloy, magnesium, lithium, magnesium / copper mixture, magnesium / silver mixture, magnesium / aluminum mixture, magnesium / indium mixture, aluminum / aluminum oxide (Al2O3) mixture. , Indium, lithium / aluminum mixtures, rare earth metals and the like.
Among these, from the point of durability against electron injection and oxidation, etc., a mixture of an electron injecting metal and a second metal which is a stable metal having a larger work function than this, for example, a magnesium / silver mixture, Magnesium / aluminum mixtures, magnesium / indium mixtures, aluminum / aluminum oxide (Al2O3) mixtures, lithium / aluminum mixtures, aluminum and the like are preferred.
The cathode can be produced by forming a thin film of these electrode materials by a method such as vapor deposition or sputtering. The sheet resistance as the cathode is preferably several hundred Ω / □ or less, and the film thickness is preferably in the range of 10 nm to 5 μm, more preferably in the range of 50 nm to 200 nm.
In order to transmit the emitted light, if either one of the anode or the cathode of the organic EL element is transparent or translucent, the emission luminance is advantageously improved.
Moreover, after producing the said metal by the film thickness of 1 nm-20 nm to a cathode, the transparent or semi-transparent cathode can be produced by producing the electroconductive transparent material quoted by description of the anode on it, By applying this, an element in which both the anode and the cathode are transmissive can be manufactured.

"substrate"
Examples of substrates that can be used in the organic EL device according to the present invention (hereinafter also referred to as “base”, “base”, “support substrate”, “support”, etc.)) include glass and plastic. There is no particular limitation, and it may be transparent or opaque. When extracting light from the substrate side, the substrate is preferably transparent. Examples of the transparent substrate preferably used include glass, quartz, and a transparent resin film. A particularly preferable substrate is a resin film capable of giving flexibility to the organic EL element.

Examples of the resin film include polyesters such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), polyethylene, polypropylene, cellophane, cellulose diacetate, cellulose triacetate, cellulose acetate butyrate, cellulose acetate propionate (CAP), Cellulose esters such as cellulose acetate phthalate (TAC) and cellulose nitrate or derivatives thereof, polyvinylidene chloride, polyvinyl alcohol, polyethylene vinyl alcohol, syndiotactic polystyrene, polycarbonate, norbornene resin, polymethylpentene, polyether ketone, polyimide , Polyethersulfone (PES), polyphenylene sulfide, polysulfones, Cycloolefin resins such as polyetherimide, polyetherketoneimide, polyamide, fluororesin, nylon, polymethylmethacrylate, acrylic or polyarylate, Arton (trade name, manufactured by JSR) or Appel (trade name, manufactured by Mitsui Chemicals) Can be mentioned.
On the surface of the resin film, an inorganic film, an organic film, or a hybrid film of both may be formed. Water vapor permeability measured by a method in accordance with JIS K 7129-1992 (25 ± 0.5 ° C., It is preferably a barrier film having a relative humidity (90 ± 2)% RH) of 0.01 g / (m 2 · 24 h) or less, and further, the oxygen permeability measured by a method according to JIS K 7126-1987. However, it is preferable that the film has a high barrier property with 1 × 10 −3 ml / (m 2 · 24 h · MPa) or less and a water vapor permeability of 1 × 10 −5 g / (m 2 · 24 h) or less.

As a material for forming the barrier film, any material may be used as long as it has a function of suppressing entry of elements that cause deterioration of elements such as moisture and oxygen. For example, silicon oxide, silicon dioxide, silicon nitride, or the like can be used. Further, in order to improve the brittleness of the film, it is more preferable to have a laminated structure of these inorganic layers and organic material layers. Although there is no restriction | limiting in particular about the lamination | stacking order of an inorganic layer and an organic layer, It is preferable to laminate | stack both alternately several times.
The method for forming the barrier film is not particularly limited. For example, the vacuum deposition method, the sputtering method, the reactive sputtering method, the molecular beam epitaxy method, the cluster ion beam method, the ion plating method, the plasma polymerization method, and the atmospheric pressure plasma. A polymerization method, a plasma CVD method, a laser CVD method, a thermal CVD method, a coating method, and the like can be used, but an atmospheric pressure plasma polymerization method as described in JP-A-2004-68143 is particularly preferable.

Examples of the opaque substrate include a metal plate such as aluminum and stainless steel, a film, an opaque resin substrate, a ceramic substrate, and the like.
The external extraction efficiency at room temperature of light emission of the organic EL device according to the present invention is preferably 1% or more, more preferably 5% or more.
Here, the external extraction quantum efficiency (%) = the number of photons emitted to the outside of the organic EL element / the number of electrons sent to the organic EL element × 100.
In addition, a hue improvement filter such as a color filter may be used in combination, or a color conversion filter that converts the emission color from the organic EL element into multiple colors using a phosphor. In the case of using a color conversion filter, the λmax of light emission of the organic EL element is preferably 480 nm or less.

<Sealing>
As a sealing means of the organic EL element used for this invention, the method of adhere | attaching a sealing member, an electrode, and a support substrate with an adhesive agent can be mentioned, for example.
As a sealing member, it should just be arrange | positioned so that the display area | region of an organic EL element may be covered, and concave plate shape or flat plate shape may be sufficient. Further, transparency and electrical insulation are not particularly limited.
Specific examples include a glass plate, a polymer plate / film, and a metal plate / film. Examples of the glass plate include soda-lime glass, barium / strontium-containing glass, lead glass, aluminosilicate glass, borosilicate glass, barium borosilicate glass, and quartz. Examples of the polymer plate include polycarbonate, acrylic, polyethylene terephthalate, polyether sulfide, and polysulfone. Examples of the metal plate include those made of one or more metals or alloys selected from the group consisting of stainless steel, iron, copper, aluminum, magnesium, nickel, zinc, chromium, titanium, molybdenum, silicon, germanium, and tantalum.
In the present invention, a polymer film and a metal film can be preferably used because the organic EL element can be thinned.
Furthermore, the polymer film has an oxygen permeability measured by a method according to JIS K 7126-1987 of 1 × 10 −3 ml / m 2/24 h or less, a water vapor measured by a method according to JIS K 7129-1992. The transmittance (25 ± 0.5 ° C., relative humidity (90 ± 2)% RH) is preferably 1 × 10 −3 g / (m 2/24 h) or less.

For processing the sealing member into a concave shape, sandblasting, chemical etching, or the like is used.
Specific examples of the adhesive include photocuring and thermosetting adhesives having reactive vinyl groups such as acrylic acid oligomers and methacrylic acid oligomers, and moisture curing adhesives such as 2-cyanoacrylates. be able to. Moreover, heat | fever and chemical curing types (two-component mixing), such as an epoxy type, can be mentioned. Moreover, hot-melt type polyamide, polyester, and polyolefin can be mentioned. Moreover, a cationic curing type ultraviolet curing epoxy resin adhesive can be mentioned.

In addition, since an organic EL element may deteriorate by heat processing, what can be adhesive-hardened from room temperature to 80 degreeC is preferable. A desiccant may be dispersed in the adhesive. Application | coating of the adhesive agent to a sealing part may use commercially available dispenser, and may print like screen printing.
It is also possible to form an inorganic or organic layer as a sealing film by covering the electrode and the organic functional layer on the outside of the electrode facing the substrate with the organic functional layer interposed therebetween, and forming an inorganic or organic layer in contact with the substrate. . In this case, the material for forming the film may be any material that has a function of suppressing intrusion of elements that cause deterioration of elements such as moisture and oxygen. For example, silicon oxide, silicon dioxide, silicon nitride, or the like may be used. it can.
Furthermore, in order to improve the brittleness of the film, it is preferable to have a laminated structure of these inorganic layers and layers made of organic materials. The method for forming these films is not particularly limited. For example, vacuum deposition, sputtering, reactive sputtering, molecular beam epitaxy, cluster ion beam method, ion plating method, plasma polymerization method, atmospheric pressure plasma A polymerization method, a plasma CVD method, a laser CVD method, a thermal CVD method, a coating method, or the like can be used.
In the gap between the sealing member and the display area of the organic EL element, an inert gas such as nitrogen or argon, or an inert liquid such as fluorinated hydrocarbon or silicon oil can be injected in the gas phase and liquid phase. preferable. A vacuum is also possible. Moreover, a hygroscopic compound can also be enclosed inside.

  Examples of the hygroscopic compound include metal oxides (for example, sodium oxide, potassium oxide, calcium oxide, barium oxide, magnesium oxide, aluminum oxide) and sulfates (for example, sodium sulfate, calcium sulfate, magnesium sulfate, cobalt sulfate). Etc.), metal halides (eg calcium chloride, magnesium chloride, cesium fluoride, tantalum fluoride, cerium bromide, magnesium bromide, barium iodide, magnesium iodide etc.), perchloric acids (eg perchloric acid) Barium, magnesium perchlorate, and the like), and anhydrous salts are preferably used in sulfates, metal halides, and perchloric acids.

《Protective film, protective plate》
In order to increase the mechanical strength of the element, a protective film or a protective plate may be provided on the outer side of the sealing film on the side facing the substrate with the organic functional layer interposed therebetween or on the sealing film. In particular, when the sealing is performed by the sealing film, the mechanical strength is not necessarily high, and thus it is preferable to provide such a protective film and a protective plate. As a material that can be used for this, the same glass plate, polymer plate / film, metal plate / film, etc. used for the sealing can be used, but the polymer film is light and thin. Is preferably used.

《Light extraction》
The organic EL element emits light within a layer having a refractive index higher than that of air (refractive index is about 1.7 to 2.1), and can extract only about 15% to 20% of the light generated in the light emitting layer. It is generally said that there is no. This is because light incident on the interface (interface between the transparent substrate and air) at an angle θ greater than the critical angle causes total reflection and cannot be taken out of the device, or between the transparent electrode or light emitting layer and the transparent substrate. This is because the light is totally reflected between the light and the light is guided through the transparent electrode or the light emitting layer, and as a result, the light escapes in the direction of the element side surface.

As a method for improving the light extraction efficiency, for example, a method of forming irregularities on the surface of the transparent substrate to prevent total reflection at the interface between the transparent substrate and the air (US Pat. No. 4,774,435), A method for improving efficiency by giving light condensing property to a substrate (Japanese Patent Laid-Open No. 63-314795), a method for forming a reflective surface on the side surface of an organic EL element (Japanese Patent Laid-Open No. 1-220394), a substrate A method of forming an antireflection film by introducing a flat layer having an intermediate refractive index between the substrate and the light emitter (Japanese Patent Laid-Open No. 62-172691), and lowering the refractive index than the substrate between the substrate and the light emitter. A method of introducing a flat layer having a structure (Japanese Patent Laid-Open No. 2001-202827), a method of forming a diffraction grating between any one of a substrate, a transparent electrode layer, and a light emitting layer (including between the substrate and the outside) No. 283751) .
In the present invention, these methods can be used in combination with the organic EL device according to the present invention. However, a method of introducing a flat layer having a lower refractive index than the substrate between the substrate and the light emitter, or a substrate, A method of forming a diffraction grating between any layers of the transparent electrode layer and the light emitting layer (including between the substrate and the outside) can be suitably used.
In the present invention, by combining these means, it is possible to obtain an organic EL device having further high luminance or durability.

When a medium with a low refractive index is formed between the transparent electrode and the transparent substrate with a thickness longer than the wavelength of light, the light extracted from the transparent electrode has a higher extraction efficiency to the outside as the refractive index of the medium is lower. .
Examples of the low refractive index layer include aerogel, porous silica, magnesium fluoride, and a fluorine-based polymer. Since the refractive index of the transparent substrate is generally about 1.5 to 1.7, the low refractive index layer preferably has a refractive index of about 1.5 or less, more preferably 1.35 or less. .
Further, the thickness of the low refractive index medium is preferably at least twice the wavelength in the medium. This is because the effect of the low refractive index layer is diminished when the thickness of the low refractive index medium is about the wavelength of light and the electromagnetic wave that has exuded by evanescent enters the substrate.
The method of introducing a diffraction grating into an interface or any medium that causes total reflection is characterized by a high effect of improving light extraction efficiency.
This method uses the property that the diffraction grating can change the direction of light to a specific direction different from refraction by so-called Bragg diffraction such as first-order diffraction and second-order diffraction. Light that cannot be emitted due to total internal reflection between layers is diffracted by introducing a diffraction grating in any layer or medium (in a transparent substrate or transparent electrode), and the light is removed. I want to take it out.
The introduced diffraction grating desirably has a two-dimensional periodic refractive index. This is because light emitted from the light-emitting layer is randomly generated in all directions, so in a general one-dimensional diffraction grating having a periodic refractive index distribution only in a certain direction, only light traveling in a specific direction is diffracted. Therefore, the light extraction efficiency does not increase so much.
However, by making the refractive index distribution a two-dimensional distribution, light traveling in all directions is diffracted, and light extraction efficiency is increased.

The position where the diffraction grating is introduced may be in any interlayer or medium (in the transparent substrate or in the transparent electrode), but is preferably in the vicinity of the organic light emitting layer where light is generated.
At this time, the period of the diffraction grating is preferably about 1/2 to 3 times the wavelength of light in the medium.
The arrangement of the diffraction grating is preferably two-dimensionally repeated such as a square lattice, a triangular lattice, or a honeycomb lattice.

<Condenser sheet>
The organic EL element according to the present invention is processed on the light extraction side of the substrate, for example, so as to provide a microlens array-like structure, or in combination with a so-called condensing sheet, for example, in a specific direction, for example, the element light emitting surface. On the other hand, the brightness | luminance in a specific direction can be raised by condensing in a front direction.
As an example of the microlens array, quadrangular pyramids having a side of 30 μm and an apex angle of 90 degrees are two-dimensionally arranged on the light extraction side of the substrate. One side is preferably 10 μm to 100 μm.
If it becomes smaller than this, the effect of diffraction will generate | occur | produce and color, and if too large, thickness will become thick and is not preferable.

As the condensing sheet, for example, a sheet that is put into practical use in an LED backlight of a liquid crystal display device can be used. As such a sheet, for example, a brightness enhancement film (BEF) manufactured by Sumitomo 3M Limited can be used.
As the shape of the prism sheet, for example, the base material may be formed by forming a △ -shaped stripe having a vertex angle of 90 degrees and a pitch of 50 μm, or the vertex angle is rounded and the pitch is changed randomly. Other shapes may be used.
Moreover, in order to control the light emission angle from a light emitting element, you may use together a light diffusing plate and a film with a condensing sheet. For example, a diffusion film (light-up) manufactured by Kimoto Co., Ltd. can be used.

<Application>
The organic EL element of the present invention can be used as a display device, a display, and various light emission sources. For example, lighting devices (home lighting, interior lighting), clock and liquid crystal backlights, billboard advertisements, traffic lights, light sources of optical storage media, light sources of electrophotographic copying machines, light sources of optical communication processors, light Although the light source of a sensor etc. are mentioned, It is not limited to this, Especially, it can use effectively for the use as a backlight of a liquid crystal display device, and a light source for illumination.

In the organic EL element of the present invention, patterning may be performed by a metal mask, an ink jet printing method, or the like as needed during film formation. In the case of patterning, only the electrode may be patterned, the electrode and the light emitting layer may be patterned, or the entire layer of the element may be patterned. In the fabrication of the element, a conventionally known method is used. Can do.
The light emission color of the organic EL device of the present invention and the compound according to the present invention is shown in FIG. 4.16 on page 108 of “New Color Science Handbook” (edited by the Japan Color Society, University of Tokyo Press, 1985). It is determined by the color applied to the CIE chromaticity coordinates as a result of measurement with a total CS-1000 (manufactured by Konica Minolta Sensing).
Further, when the organic EL element according to the present invention is a white element, white means that the chromaticity in the CIE 1931 color system at 1000 cd / m 2 is measured when the 2 ° viewing angle front luminance is measured by the above method. It is in the region of X = 0.33 ± 0.07 and Y = 0.33 ± 0.1.

[Display device]
The display device according to the present invention includes the organic EL element of the present invention. The display device of the present invention may be single color or multicolor, but here, the multicolor display device will be described. In the case of a multicolor display device, a shadow mask is provided only at the time of forming a light emitting layer, and a film can be formed on one surface by a vapor deposition method, a casting method, a spin coating method, an ink jet method, a printing method, or the like.
In the case of patterning only the light emitting layer, the method is not limited. However, the vapor deposition method, the ink jet method, the spin coating method, and the printing method are preferable.

The configuration of the organic EL element provided in the display device is selected from the above-described configuration examples of the organic EL element as necessary.
Moreover, the manufacturing method of an organic EL element is as having shown to the one aspect | mode of manufacture of the organic EL element of said invention.
In the case of applying a DC voltage to the obtained multicolor display device, light emission can be observed by applying a voltage of about 2V to 40V with the positive polarity of the anode and the negative polarity of the cathode. Further, even when a voltage is applied with the opposite polarity, no current flows and no light emission occurs. Further, when an AC voltage is applied, light is emitted only when the anode is in the + state and the cathode is in the-state. The alternating current waveform to be applied may be arbitrary.
The multicolor display device can be used as a display device, a display, and various light emission sources. In display devices and displays, full-color display is possible by using three types of organic EL elements of blue, red, and green light emission.
Examples of the display device and display include a television, a personal computer, a mobile device, an AV device, a character broadcast display, and an information display in an automobile. In particular, it may be used as a display device for reproducing still images and moving images, and the driving method when used as a display device for reproducing moving images may be either a simple matrix (passive matrix) method or an active matrix method.
Light emitting sources include home lighting, interior lighting, clock and liquid crystal backlights, billboard advertisements, traffic lights, light sources for optical storage media, light sources for electrophotographic copying machines, light sources for optical communication processors, light sources for optical sensors, etc. However, the present invention is not limited to these.

Hereinafter, an example of a display device having the organic EL element of the present invention will be described with reference to the drawings.
FIG. 1 is a schematic diagram illustrating an example of a display device including organic EL elements. It is a schematic diagram of a display such as a mobile phone that displays image information by light emission of an organic EL element.
The display 1 includes a display unit A having a plurality of pixels, a control unit B that performs image scanning of the display unit A based on image information, and the like.
The control unit B is electrically connected to the display unit A, and sends a scanning signal and an image data signal to each of a plurality of pixels based on image information from the outside. The image information is sequentially emitted to scan the image and display the image information on the display unit A.

FIG. 2 is a schematic diagram of the display unit A.
The display unit A includes a wiring unit including a plurality of scanning lines 5 and data lines 6, a plurality of pixels 3 and the like on a substrate. The main members of the display unit A will be described below.
FIG. 2 shows a case where the light emitted from the pixel 3 is extracted in the direction of the white arrow (downward). The scanning lines 5 and the plurality of data lines 6 in the wiring portion are each made of a conductive material, and the scanning lines 5 and the data lines 6 are orthogonal to each other in a grid pattern and are connected to the pixels 3 at orthogonal positions (details are shown in the figure). Not) When a scanning signal is applied from the scanning line 5, the pixel 3 receives an image data signal from the data line 6 and emits light according to the received image data.
Full-color display is possible by appropriately arranging pixels in the red region, the green region, and the blue region on the same substrate.

Next, the light emission process of the pixel will be described.
FIG. 3 is a schematic diagram of a pixel. The pixel includes an organic EL element 10, a switching transistor 11, a driving transistor 12, a capacitor 13, and the like. A full color display can be performed by using red, green, and blue light emitting organic EL elements as the organic EL elements 10 in a plurality of pixels, and juxtaposing them on the same substrate.
In FIG. 3, an image data signal is applied from the control unit B to the drain of the switching transistor 11 through the data line 6. When a scanning signal is applied from the control unit B to the gate of the switching transistor 11 via the scanning line 5, the driving of the switching transistor 11 is turned on, and the image data signal applied to the drain is supplied to the capacitor 13 and the driving transistor 12. Is transmitted to the gate.
By transmitting the image data signal, the capacitor 13 is charged according to the potential of the image data signal, and the drive of the drive transistor 12 is turned on. The drive transistor 12 has a drain connected to the power supply line 7 and a source connected to the electrode of the organic EL element 10, and the power supply line 7 connects to the organic EL element 10 according to the potential of the image data signal applied to the gate. Current is supplied.
When the scanning signal is moved to the next scanning line 5 by the sequential scanning of the control unit B, the driving of the switching transistor 11 is turned off. However, even if the driving of the switching transistor 11 is turned off, the capacitor 13 maintains the potential of the charged image data signal, so that the driving of the driving transistor 12 is kept on and the next scanning signal is applied. Until then, the light emission of the organic EL element 10 continues. When the scanning signal is next applied by sequential scanning, the driving transistor 12 is driven according to the potential of the next image data signal synchronized with the scanning signal, and the organic EL element 10 emits light.
That is, the organic EL element 10 emits light by the switching transistor 11 and the drive transistor 12 that are active elements for the organic EL element 10 of each of the plurality of pixels, and the light emission of the organic EL element 10 of each of the plurality of pixels 3. It is carried out. Such a light emitting method is called an active matrix method.
Here, the light emission of the organic EL element 10 may be light emission of a plurality of gradations by a multi-value image data signal having a plurality of gradation potentials, or by turning on / off a predetermined light emission amount by a binary image data signal. Good. The potential of the capacitor 13 may be maintained until the next scanning signal is applied, or may be discharged immediately before the next scanning signal is applied.
In the present invention, not only the active matrix method described above, but also a passive matrix light emission drive in which the organic EL element emits light according to the data signal only when the scanning signal is scanned.

FIG. 4 is a schematic view of a passive matrix display device.
In FIG. 4, a plurality of scanning lines 5 and a plurality of image data lines 6 are provided in a lattice shape so as to face each other with the pixel 3 interposed therebetween.
When the scanning signal of the scanning line 5 is applied by sequential scanning, the pixels 3 connected to the applied scanning line 5 emit light according to the image data signal.
In the passive matrix system, the pixel 3 has no active element, and the manufacturing cost can be reduced.

[Lighting device]
The organic EL element of the present invention may be used as an organic EL element having a resonator structure. The purpose of use of the organic EL element having such a resonator structure is as follows. The light source of a machine, the light source of an optical communication processing machine, the light source of a photosensor, etc. are mentioned, However, It is not limited to these. Moreover, you may use for the said use by making a laser oscillation.
Further, the organic EL element of the present invention may be used as a kind of lamp for illumination or exposure light source, a projection device for projecting an image, or a display for directly viewing a still image or a moving image. It may be used as a device (display).
The driving method when used as a display device for moving image reproduction may be either a simple matrix (passive matrix) method or an active matrix method. Alternatively, it is possible to produce a full-color display device by using two or more organic EL elements of the present invention having different emission colors.

The organic EL material of the present invention can be applied to an organic EL element that emits substantially white light as a lighting device. A plurality of light emitting colors are simultaneously emitted by a plurality of light emitting materials to obtain white light emission by color mixing. The combination of a plurality of emission colors may include three emission maximum wavelengths of three primary colors of blue, green, and blue, or two of the complementary colors such as blue and yellow, blue green and orange, etc. The thing containing the light emission maximum wavelength may be used.
In addition, a combination of light emitting materials for obtaining a plurality of emission colors is a combination of a plurality of phosphorescent or fluorescent materials, a light emitting material that emits fluorescence or phosphorescence, and excitation of light from the light emitting materials. Any combination with a dye material that emits light as light may be used, but in the white organic EL device according to the present invention, it is only necessary to mix and mix a plurality of light emitting dopants.
It is only necessary to provide a mask only when forming a light emitting layer, a hole transport layer, an electron transport layer, etc., and simply arrange them separately by coating with the mask. Since other layers are common, patterning of the mask or the like is not necessary. In addition, for example, an electrode film can be formed by a vapor deposition method, a cast method, a spin coating method, an ink jet method, a printing method, or the like, and productivity is also improved.
According to this method, unlike a white organic EL device in which light emitting elements of a plurality of colors are arranged in parallel in an array, the elements themselves are luminescent white.
There is no restriction | limiting in particular as a luminescent material used for a light emitting layer, For example, if it is a backlight in a liquid crystal display element, the metal complex which concerns on this invention so that it may adapt to the wavelength range corresponding to CF (color filter) characteristic, Any one of known luminescent materials may be selected and combined to whiten.

<< One Embodiment of Lighting Device of the Present Invention >>
One aspect of the lighting device of the present invention that includes the organic EL element of the present invention will be described.
The non-light-emitting surface of the organic EL device of the present invention is covered with a glass cover, a 300 μm thick glass substrate is used as a sealing substrate, and an epoxy-based photocurable adhesive (LUX The track LC0629B) is applied, and this is overlaid on the cathode and brought into close contact with the glass substrate, irradiated with UV light from the glass substrate side, cured and sealed, and an illumination device as shown in FIGS. Can be formed.
FIG. 5 shows a schematic view of the lighting device, and FIG. 6 shows a cross-sectional view of the lighting device. As shown in FIG. 5, the lighting device 100 is configured by covering an organic EL element 101 with a glass cover 102. (The sealing operation with the glass cover 102 was performed in a glove box under a nitrogen atmosphere (in an atmosphere of high-purity nitrogen gas having a purity of 99.999% or more) without bringing the organic EL element 101 into contact with the atmosphere. ).
As shown in FIG. 6, the organic EL element 101 includes an anode 107 provided on a glass substrate 103 and a cathode 105, and includes an organic function including a light emitting layer provided between the anode 107 and the cathode 105. Layer 106. The glass cover 101 is sealed on the glass substrate 103 via an adhesive layer 104 or the like. The glass cover 102 is filled with nitrogen gas 108 and a water catching agent 109 is provided.

比較化合物Ａ

比較化合物Ｂ EXAMPLES Hereinafter, although an Example demonstrates this invention, this invention is not limited to these.
The structures of the compounds used in the examples are shown below.

Comparative compound A

Comparative compound B

(1) Example 1
<< Production of Organic EL Element 1-1 >>
Patterning was performed so that a light emitting area of 50 mm × 50 mm was obtained on a substrate (NH-Techno Glass NA-45) formed by depositing 100 nm of ITO (indium tin oxide) on a 100 mm × 100 mm × 1.1 mm glass substrate as an anode. Thereafter, the transparent support substrate provided with the ITO transparent electrode was ultrasonically cleaned with isopropyl alcohol, dried with dry nitrogen gas, and subjected to UV ozone cleaning for 5 minutes.
This transparent support substrate was put into a commercially available vacuum deposition apparatus, and after reducing the pressure to 4 × 10 −4 Pa or less, CuPc (copper phthalocyanine) was deposited as a hole injection layer to provide a 20 nm hole injection layer.
Subsequently, HT-2 was evaporated to a thickness of 20 nm to form a hole transport layer, and a light emitting layer having a dopant concentration of 6% as a host material and compound G-1 as a dopant material and PD-12 as a dopant material was formed thereon. 30 nm was deposited. Further, 30 nm of ET-5 was deposited to form an electron transport layer, 0.5 nm of lithium fluoride was subsequently deposited to form an electron injection layer, 120 nm of aluminum was deposited to form a cathode, and the organic EL device 1-1 was formed. did.

<< Production of Organic EL Elements 1-2 to 1-20 >>
In the production of the organic EL device 1-1, the host compound and the luminescent dopant (phosphorescent compound) were mixed with the compounds shown in Table 1 below (equal to the weights of G-1 and PD-12 of the organic EL device 1-1). Organic EL elements 1-2 to 1-20 were respectively produced in the same manner except that the above was changed.

<< Evaluation of Organic EL Elements 1-1 to 1-20 >>
When evaluating the obtained organic EL elements 1-1 to 1-20, the non-light-emitting surface of each organic EL element after production was covered with a glass case, and a glass substrate having a thickness of 300 μm was used as a sealing substrate. In addition, an epoxy-based photo-curing adhesive (Lux Track LC0629B manufactured by Toagosei Co., Ltd.) is applied as a sealing material in the periphery, and this is placed on the cathode so as to adhere to the transparent support substrate, and UV light is emitted from the glass substrate side. Irradiation, curing and sealing were carried out, and an illumination device as shown in FIGS. 5 and 6 was formed and evaluated.

"efficiency"
About the produced organic EL element, external extraction quantum efficiency (%) when ^2.5 mA / cm ² constant current was applied in a dry nitrogen gas atmosphere at 23 ° C. was measured. For the measurement, a spectral radiance meter CS-1000 (manufactured by Konica Minolta Sensing) was used. The measurement results are shown in Table 1 below.

<Luminescent life>
When driving at a constant current of ^2.5 mA / cm ^{2 in} a dry nitrogen gas atmosphere at 23 ° C., the time required for the luminance to drop to half of the luminance immediately after the start of light emission (initial luminance) was measured. Was used as an index of life as half-life time (τ0.5). The obtained results are shown in Table 1 below.
Similarly, a spectral radiance meter CS-1000 (manufactured by Konica Minolta Sensing) was used for the measurement. The results of the external extraction quantum efficiency and the light emission lifetime of the organic EL elements 1-1 to 1-20 were evaluated relative to the organic EL element 1-19 as 100.

《Thermal stability》
After storing at 85 ° C. for 24 hours, the brightness when driven at a constant current of ^2.5 mA / cm ² before and after storage was measured, and the brightness ratio before and after storage was determined according to the following formula, which was used as a measure of heat resistance. .
Heat resistance (%) = luminance after storage (2.5 mA / cm 2) / luminance before storage (2.5 mA / cm 2) × 100
The obtained results are shown in Table 1 below.

(2) Example 2
<< Production of White Light-Emitting Element and White Light-Emitting Lighting Device-1 >>
In the production of the organic EL element 1-1 produced in Example 1, the white light-emitting organic EL element 1-1W was similarly obtained except that PD-12 was changed to a mixture of PD-1, PD-10 and PD-12. Was made.
The obtained organic EL device 1-1W was covered with a glass case on the non-light-emitting surface in the same manner as in the above-described example to obtain a lighting device. When this lighting device was energized, it was found that substantially white light was obtained and it could be used as a lighting device.

≪Production of comparative white light emitting element and white lighting device≫
A white light emitting device was prepared in the same manner except that Compound G-1 of the present invention was replaced with Comparative Compound A and Comparative Compound B in Preparation of White Light Emitting Device and White Lighting Device-1, respectively. When a device using Comparative Compound A and Comparative Compound B was energized, white light emission was not obtained, and only light emission close to red was obtained.

DESCRIPTION OF SYMBOLS 1 Display 3 Pixel 5 Scan line 6 Data line 7 Power supply line 10 Organic EL element 11 Switching transistor 12 Drive transistor 13 Capacitor A Display part B Control part 100 Illuminating device 101 Organic EL element 102 Glass cover 103 Glass substrate 104 Adhesive layer 105 Cathode 106 Organic functional layer 107 Anode 108 Nitrogen gas 109 Water trapping agent

Claims (8)

An organic electroluminescent element material represented by the following general formula (1).

General formula (1)
(In General Formula (1), Ar ₁ and Ar ₂ each represent an aromatic hydrocarbon group or an aromatic heterocyclic group . Y _{1 to} Y ₈ each represent a nitrogen atom or CR _{1 to} CR ₈ . ₁ , R ₂ , R ₄ , R ₅ , R ₇ and R ₈ are each a hydrogen atom, an alkyl group, an aromatic hydrocarbon group, an aromatic heterocyclic group, an amino group, a silyl group, a germyl group, or a stannyl group. . the representative R ₃ and R ₆ .X each represent a hydrogen atom is a single _{bond, -CR 9 R 10 -, -} CR 11 = CR 12 -, - SiR 13 R 14 -, - O -, - NR 15 - _{, -S -, - PR 16 -} , - P (= O) R 17 -, - GeR 18 R 19 -, or _{-SnR 20 R 21 - .R 9 ~R} 21 representing a are each a hydrogen atom, an aromatic substituted hydrocarbon group, or an aromatic heterocyclic group. Ar _1, Ar ₂ and any one or more of _R 1 to R ₈ has a carbazole as a partial structure A representative.)   In the said General formula (1), X is a single bond, The organic electroluminescent element material of Claim 1 characterized by the above-mentioned. In the general formula (1), an organic electroluminescence device material according to claim 1 or 2, characterized in that Ar ₁ and Ar ₂ are bonded to form a condensed ring. An organic electroluminescent device comprising a plurality of organic functional layers including a light emitting layer containing at least a host compound and a phosphorescent compound between an anode and a cathode,
The organic electroluminescent element characterized by containing the organic electroluminescent element material as described in any one of Claims 1-3 as said host compound. The organic electroluminescence device according to claim 4, wherein at least one of the phosphorescent compounds is an iridium compound represented by the following general formula (2).

General formula (2)
(In General Formula (2), Q1 represents a 5- or 6-membered aromatic ring or aromatic heterocyclic ring. Ar ₃ represents an aromatic hydrocarbon group or an aromatic heterocyclic group. K represents 2 Or, it represents an integer of 3 and has m subligands L so as to satisfy the valence of iridium. M represents 0 or 1.)   6. The organic electroluminescence element according to claim 4, wherein the organic electroluminescence element is a white organic electroluminescence element that emits white light.   The organic electroluminescent element as described in any one of Claims 4-6 is comprised, The display apparatus characterized by the above-mentioned.   The organic electroluminescent element as described in any one of Claims 4-6 is comprised, The illuminating device characterized by the above-mentioned.

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