JP2013033915A - Organic electroluminescent element, display device, and lighting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To achieve a reduction in driving voltage and an improvement in emission life.SOLUTION: An organic electroluminescent element comprises: an anode 107; a cathode 105; and an organic layer 106 composed of one or a plurality of layers including at least a light-emitting layer. The organic layer 106 is disposed between the anode 107 and the cathode 105. At least one layer of the organic layer 106 contains a specific hexadentate coordination type iridium ortho-metal complex.

Description

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

  An organic electroluminescence element (hereinafter also referred to as an organic EL element) has a structure in which a light emitting layer containing a light emitting compound is sandwiched between a cathode and an anode, and recombines by injecting electrons and holes into the light emitting layer. Is an element that emits light by using the emission of light (fluorescence / phosphorescence) when excitons are generated by excitons, and can emit light at a voltage of several volts to several tens of volts. Therefore, it is attracting attention as a next-generation flat display and illumination.

  Since an organic EL device using phosphorescence emission from an excited triplet whose upper limit of internal quantum efficiency is 100% has been reported by Princeton University (for example, see Non-Patent Document 1), a material that exhibits phosphorescence at room temperature (See, for example, Non-Patent Document 2 and Patent Document 1).

  Further, iridium complex-based heavy metal complexes have been studied as materials that exhibit phosphorescence at room temperature (see, for example, Non-Patent Document 3).

  For example, a tris (2-phenylpyridine) iridium complex is widely known (see Non-Patent Document 2), and a tris (2-phenylpyridine) skeleton has a silyl group for the purpose of improving the durability and luminous efficiency of the dopant. An iridium complex having a ligand into which a group is introduced is disclosed (for example, see Patent Document 2).

  However, even in an organic EL device using these dopants, sufficient device performance including a light emission lifetime has not been obtained.

  In addition to tris (2-phenylpyridine) iridium complexes, iridium complexes having phenylimidazole ligands or carbene ligands are disclosed (see, for example, Patent Documents 3 and 4).

  These materials have a shallower HOMO than a complex composed of phenylpyridine ligands, increase the hole-injection barrier, and reorient as molecules when a bulky substituent is introduced to shorten the wavelength. There is a problem that energy is increased, charge transport ability is lowered, and driving voltage is increased as a result.

  On the other hand, a complex in which a ligand of an iridium complex is bonded is disclosed (see Patent Documents 5 and 6).

  In these complexes, the thermal stability of the material itself is improved and the lifetime of the device is also improved. However, there is no disclosure regarding improvement of the driving voltage especially when light having a short wavelength is obtained using a material having a shallow HOMO. Absent.

US Pat. No. 6,097,147 JP 2005-327526 A International Publication No. 2006/046980 International Publication No. 2005/019373 International Publication No. 2005/76380 International Publication No. 2004/81017

M.M. A. Baldo et al. , Nature, 395, 151-154 (1998) M.M. A. Baldo et al. , Nature, 403, 17, 750-753 (2000) C. Adachi et al. , Appl. Phys. Lett. 79, 2082-2084 (2001)

A main object of the present invention is to provide an organic electroluminescence element that exhibits high light emission efficiency and can reduce drive voltage and light emission life.
Another object of the present invention is to provide an organic electroluminescence element material used for forming such an element, and an illumination device and a display device including the element.

In order to solve the above problems, according to the present invention,
In an organic electroluminescence device comprising an anode, a cathode, and an organic layer composed of one or more layers having at least a light emitting layer, wherein the organic layer is disposed between the anode and the cathode.
There is provided an organic electroluminescence device characterized in that at least one of the organic layers contains a constant hexadentate iridium orthometal complex.

  ADVANTAGE OF THE INVENTION According to this invention, the organic electroluminescent element which shows high luminous efficiency and can aim at the reduction of a drive voltage and the improvement of the light emission lifetime can be provided.

It is the schematic of the illuminating device concerning an Example sample. It is sectional drawing of the illuminating device concerning an Example sample.

  Hereinafter, it is preferable embodiment of this invention, Comprising: The detail of each component of the organic electroluminescent element of this invention is demonstrated one by one.

An ortho metal iridium complex having a 5-membered ring as a component of the ligand is interesting because it can emit light at a shorter wavelength than a phenylpyridine-based ortho metal iridium complex composed of only a 6-membered ring. However, the device life and high light emission efficiency that can still be put into practical use have not been obtained.
The present inventors have found that the ortho metal iridium complex of a ligand having a 5-membered ring has a shallow HOMO as compared with a phenyl pyridine type ortho metal iridium complex, poor hole injection, and increased driving voltage. In addition, conventionally known ortho metal iridium complexes are prone to agglomeration of metal complexes in the constituent layers of the organic EL device, and the device life and high luminous efficiency that can be put to practical use are not obtained. We estimated that the problem was intensively studied.

  As a result, in the ortho metal iridium complex having a 5-membered ring as a component of the ligand, the device lifetime is improved by using a certain compound represented by the general formula (1) (see below), and It has been found that the drive voltage can be reduced.

  Rather than linking the aromatic ring, which is a component of the ligand, with a single linking group, the adjacent ligands are linked together to suppress aggregation of metal complexes in the constituent layers of the organic EL device. Since it was possible to suppress TT annihilation occurring between exciton triplets of the metal complex, it was estimated that the lifetime of the device was improved.

  In addition, the introduction of these substituents seems to increase the reorientation energy. However, by combining each of the three ligands in the manner of the present invention, the driving voltage of the organic EL element is reduced, and the emission luminance is increased. It was also found that the emission lifetime is improved.

《Orthometal Iridium Complex》
The ortho metal iridium complex of the present invention will be described.

  The ortho metal iridium complex of the present invention can be used in any one of the constituent layers (organic compound layers) of the organic EL device of the present invention. However, the effect of the present invention (light emission efficiency of the device (specifically, external extraction) From the viewpoint of sufficiently improving (quantum efficiency, also simply referred to as efficiency), increasing half-life, and lowering driving voltage), as a light-emitting dopant (also simply referred to as a dopant) in the light-emitting layer of the device and further in the light-emitting layer It is preferable to use it.

  The constituent layers of the organic EL element of the present invention will be described in detail later.

  The ortho metal iridium complex of the present invention is specifically represented by the general formula (1).

  In the general formula (1), L1, L2, and L3 each have a bidentate ligand structure, and are bonded to iridium at two positions by the coordinating atoms of each.

V1, V2, and V3 represent a divalent linking group.
Examples of the divalent linking group include an alkylene group (eg, methylene group, ethylene group, trimethylene group, propylene group, etc.), a cycloalkylene group (eg, 1,2-cyclobutanediyl group, 1,2-cyclopentanediyl group, 1,3-cyclopentanediyl group, 1,2-cyclohexanediyl group, 1,3-cyclohexanediyl group, 1,4-cyclohexanediyl group, 1,2-cycloheptanediyl group, 1,3-cycloheptanediyl group , 1,4-cycloheptanediyl group, etc.), arylene group (for example, o-phenylene group, m-phenylene group, p-phenylene group, 1,2-naphthylene group, 2,3-naphthylene group, 1,3 -Naphthylene group, 1,4-naphthylene group, 2,7-naphthylene group, etc.), heteroarylene group (for example, thiophene-2,5-diyl group, 2,6-pyridinediyl group, 2,3-pyridinediyl group) 2,4-pyridinediyl group, 2,4-dibenzofuran Yl group, 2,8-dibenzofurandiyl group, 4,6-dibenzofurandiyl group, 3,7-dibenzofurandiyl group, 2,4-dibenzothiophenediyl group, 2,8-dibenzothiophenediyl group, 4,6-dibenzo Thiophenediyl group, 3,7-dibenzothiophenediyl group, 1,3-carbazolediyl group, 1,8-carbazolediyl group, 3,6-carbazolediyl group, 2,7-carbazolediyl group, 1,9-carbazole Diyl group, 2,9-carbazolediyl group, 3,9-carbazolediyl group, 4,9-carbazolediyl group, etc.), -O- group, -CO- group, -O-CO- group, -CO- And a group formed by combining a plurality of O-groups, -O-CO-O- groups, -S- groups, -SO- groups, -SO2- groups, and -NR- groups.
Here, R is an optionally substituted alkyl group (for example, methyl group, ethyl group, propyl group, isopropyl group, tert-butyl group, pentyl group, hexyl group, octyl group, dodecyl group, tridecyl group, tetradecyl group). Group, pentadecyl group, etc.), cycloalkyl group (eg, cyclopentyl group, cyclohexyl group, etc.), arylalkyl group (benzyl group, phenethyl group, diphenylmethyl group, 1,1-diphenylethyl group, 1,2-diphenylethyl group) Etc.), aryl group (for example, phenyl group, p-chlorophenyl group, mesityl group, tolyl group, xylyl group, naphthyl group, anthryl group, azulenyl group, acenaphthenyl group, fluorenyl group, phenanthryl group, indenyl group, pyrenyl group, biphenylyl Group), heteroaryl group (for example, pyridyl group) Pyrimidinyl group, furyl group, pyrrolyl group, imidazolyl group, benzimidazolyl group, pyrazolyl group, pyrazinyl group, triazolyl group (for example, 1,2,4-triazol-1-yl group, 1,2,3-triazol-1-yl group) Group), oxazolyl group, benzoxazolyl group, thiazolyl group, isoxazolyl group, isothiazolyl group, furazanyl group, thienyl group, quinolyl group, benzofuryl group, dibenzofuryl group, benzothienyl group, dibenzothienyl group, indolyl group, carbazolyl Group, carbolinyl group, diazacarbazolyl group (in which one of the carbon atoms constituting the carboline ring of the previous carbolinyl group is replaced by a nitrogen atom), quinoxalinyl group, pyridazinyl group, triazinyl group, quinazolinyl group, phthalazinyl group Etc.), non-aromatic carbonization Hydrogen ring group (for example, 1,2,3,4-tetrahydronaphthalen-5-yl group, 9,9,10,10-tetramethyl-9,10-dihydroanthracen-2-yl group, biphenylene-1-yl group) Or non-aromatic heterocyclic group (for example, pyrrolidyl group, imidazolidyl group, oxazolidyl group, morpholyl group, thiomorpholinyl group, tetrahydrofuran-2-yl group, 10H-phenoxazin-3-yl group, phenoxathiin-3 -Yl group, chroman-2-one-6-yl group, 2,3,4,9-tetrahydro-1H-carbazol-7-yl group and the like.

  The linking group is preferably an alkylene group, a group in which two alkylene groups are linked by a cycloalkylene group, a group in which two alkylene groups are linked by an arylene group or a heteroarylene group, two alkylene groups are -O- groups,- A group selected from the group consisting of CO-, -O-CO-, -CO-O-, -O-CO-O-, -S-, -SO-, -SO2- and -NR- Two alkylene groups connected by an alkylene group, an arylene group or a heteroarylene group and an -O- group, -CO- group, -O-CO- group, -CO-O- group, -O-CO-O A group connected by a combination of groups selected from -group, -S- group, -SO- group, -SO2- group, and -NR- group, a group in which two cycloalkylene groups are connected by an alkylene group, and two cycloalkylenes A group in which a group is connected by an arylene group or a heteroarylene group, and two cycloalkylene groups are -O- group, -CO- group, -O-CO- group, -CO-O- group, -O-CO-O- Group, -S- group, -SO- group, -SO2- group, -NR- group Or a group linked by a combination thereof, an alkylene group, an arylene group or a heteroarylene group and an —O— group, an —CO— group, an —O—CO— group, an —CO—O— group. , —O—CO—O— group, —S— group, —SO— group, —SO 2 — group, a group linked by a combination of groups selected from —NR— group.

The linking group may have a substituent.
Examples of the substituent include a halogen atom, a cyano group, or an optionally substituted alkyl group (for example, methyl group, ethyl group, propyl group, isopropyl group, tert-butyl group, pentyl group, hexyl group, octyl group, dodecyl group). Group, tridecyl group, tetradecyl group, pentadecyl group, etc.), cycloalkyl group (eg, cyclopentyl group, cyclohexyl group, etc.), alkenyl group (eg, vinyl group, allyl group, etc.), alkynyl group (eg, ethynyl group, propargyl group, etc.) Etc.), alkoxy groups (for example, methoxy group, ethoxy group, propyloxy group, pentyloxy group, hexyloxy group, octyloxy group, dodecyloxy group, etc.), cycloalkyloxy groups (for example, cyclopentyloxy group, cyclohexyloxy group) Etc.), amino group (for example, amino Group, ethylamino group, dimethylamino group, butylamino group, cyclopentylamino group, 2-ethylhexylamino group, dodecylamino group, anilino group, naphthylamino group, 2-pyridylamino group, etc.), silyl group (for example, trimethylsilyl group, Triisopropylsilyl group, triphenylsilyl group, phenyldiethylsilyl group, etc.), arylalkyl group (benzyl group, phenethyl group, diphenylmethyl group, 1,1-diphenylethyl group, 1,2-diphenylethyl group, etc.), aryl Groups (for example, phenyl group, p-chlorophenyl group, mesityl group, tolyl group, xylyl group, naphthyl group, anthryl group, azulenyl group, acenaphthenyl group, fluorenyl group, phenanthryl group, indenyl group, pyrenyl group, biphenylyl group, etc.), Heteroaryl groups (eg, Pyridyl group, pyrimidinyl group, furyl group, pyrrolyl group, imidazolyl group, benzoimidazolyl group, pyrazolyl group, pyrazinyl group, triazolyl group (for example, 1,2,4-triazol-1-yl group, 1,2,3-triazole- 1-yl group, etc.), oxazolyl group, benzoxazolyl group, thiazolyl group, isoxazolyl group, isothiazolyl group, furazanyl group, thienyl group, quinolyl group, benzofuryl group, dibenzofuryl group, benzothienyl group, dibenzothienyl group, indolyl Group, carbazolyl group, carbolinyl group, diazacarbazolyl group (in which one of the carbon atoms constituting the carboline ring of the previous carbolinyl group is replaced by a nitrogen atom), quinoxalinyl group, pyridazinyl group, triazinyl group, quinazolinyl group , Phthalazinyl group, etc.) A reeloxy group (for example, phenoxy group, p-chlorophenoxy group, mesityloxy group, tolyloxy group, xylyloxy group, naphthyloxy group, anthryloxy group, azulenyloxy group, acenaphthenyloxy group, fluorenyloxy group, phenane Tolyloxy group, indenyloxy group, pyrenyloxy group, biphenylyloxy group, etc.), heteroaryloxy group (for example, pyridyloxy group, pyrimidinyloxy group, furyloxy group, pyrrolyloxy group, imidazolyloxy group, benzoimidazolyloxy group) Group, pyrazolyloxy group, pyrazinyloxy group, triazolyloxy group (for example, 1,2,4-triazol-1-yloxy group, 1,2,3-triazol-1-yloxy group, etc.), oxazolyloxy group, Benzoo Sazolyloxy, thiazolyloxy, isoxazolyloxy, isothiazolyloxy, furazanyloxy, thienyloxy, quinolyloxy, benzofuryloxy, dibenzofuryloxy, benzothienyloxy, dibenzothienyloxy, in Drilloxy, carbazolyloxy, carbolinyloxy, etc.), non-aromatic hydrocarbon ring groups (eg 1,2,3,4-tetrahydronaphthalen-5-yl group, 9,9,10, 10-tetramethyl-9,10-dihydroanthracen-2-yl group, biphenylene-1-yl group, etc.) or non-aromatic heterocyclic group (eg pyrrolidyl group, imidazolidyl group, oxazolidyl group, morpholyl group, thiomorpholinyl group, Tetrahydrofuran-2-yl group, 10H-phenoxazin-3-yl group, phenoxathiin-3-yl group, chroman-2-one-6- Yl group, 2,3,4,9-tetrahydro-1H-carbazol-7-yl group, etc.).

  Examples of the linking groups V1, V2, and V3 are given below, but the present invention is not limited thereto.

  L1 and L2 are linked by a linking group V1, L2 and L3 are linked by a linking group V2, and L3 and L1 are linked by a linking group V3 to form a hexadentate ligand (Lig) represented by the general formula (2). doing. n represents 0 or 1, and when n = 0, the linking group V3 does not exist.

  In general formula (2), L1, L2, and L3 each have a partial structure shown in general formula (3). L1, L2, and L3 may be the same or different from each other.

In general formula (3), CyD1, CyD2, and CyD3 may be the same as or different from each other, and represent an aromatic heterocycle that is coordinated to iridium by a nitrogen atom or a carbene carbon atom, and CyC1 , CyC2, and CyC3 may be the same or different from each other, and each represents an aromatic hydrocarbon ring or an aromatic heterocycle in which a carbon atom is bonded to iridium by a covalent bond.
CyD1 and CyC1 are covalently linked by a linking group or a single bond V11 to form a bidentate ligand structure, and CyD2 and CyC2 are covalently linked by a linking group or a single bond V12 to be bidentate-coordinated. It becomes a child structure, and CyD3 and CyC3 are linked by a covalent bond with V13 which is a linking group or a single bond to form a bidentate ligand structure.

V11, V12 and V13 may be the same as or different from each other, and each represents a single bond or a linking group.
When V11, V12 and V13 are linking groups, the linking groups are> CH2 group,> CHR 'group,>CR'R"group,>SiR'R"group,> BR group,> NR group,> PR group. , —O— group, —S— group, and> C═O group.
Here, R is an optionally substituted alkyl group (for example, methyl group, ethyl group, propyl group, isopropyl group, tert-butyl group, pentyl group, hexyl group, octyl group, dodecyl group, tridecyl group, tetradecyl group). Group, pentadecyl group, etc.), cycloalkyl group (eg, cyclopentyl group, cyclohexyl group, etc.), arylalkyl group (benzyl group, phenethyl group, diphenylmethyl group, 1,1-diphenylethyl group, 1,2-diphenylethyl group) Etc.), aryl group (for example, phenyl group, p-chlorophenyl group, mesityl group, tolyl group, xylyl group, naphthyl group, anthryl group, azulenyl group, acenaphthenyl group, fluorenyl group, phenanthryl group, indenyl group, pyrenyl group, biphenylyl Group), heteroaryl group (for example, pyridyl group) Pyrimidinyl group, furyl group, pyrrolyl group, imidazolyl group, benzimidazolyl group, pyrazolyl group, pyrazinyl group, triazolyl group (for example, 1,2,4-triazol-1-yl group, 1,2,3-triazol-1-yl group) Group), oxazolyl group, benzoxazolyl group, thiazolyl group, isoxazolyl group, isothiazolyl group, furazanyl group, thienyl group, quinolyl group, benzofuryl group, dibenzofuryl group, benzothienyl group, dibenzothienyl group, indolyl group, carbazolyl Group, carbolinyl group, diazacarbazolyl group (in which one of the carbon atoms constituting the carboline ring of the previous carbolinyl group is replaced by a nitrogen atom), quinoxalinyl group, pyridazinyl group, triazinyl group, quinazolinyl group, phthalazinyl group Etc.), non-aromatic carbonization Hydrogen ring group (for example, 1,2,3,4-tetrahydronaphthalen-5-yl group, 9,9,10,10-tetramethyl-9,10-dihydroanthracen-2-yl group, biphenylene-1-yl group) Or non-aromatic heterocyclic group (for example, pyrrolidyl group, imidazolidyl group, oxazolidyl group, morpholyl group, thiomorpholinyl group, tetrahydrofuran-2-yl group, 10H-phenoxazin-3-yl group, phenoxathiin-3 -Yl group, chroman-2-one-6-yl group, 2,3,4,9-tetrahydro-1H-carbazol-7-yl group and the like.
R ′ and R ″ each independently represents an alkyl group which may be substituted (for example, methyl group, ethyl group, propyl group, isopropyl group, tert-butyl group, pentyl group, hexyl group, octyl group, dodecyl group, Tridecyl group, tetradecyl group, pentadecyl group, etc.), cycloalkyl group (eg, cyclopentyl group, cyclohexyl group, etc.), alkoxy group (eg, methoxy group, ethoxy group, propyloxy group, pentyloxy group, hexyloxy group, octyloxy group) Group, dodecyloxy group, etc.), cycloalkyloxy group (eg, cyclopentyloxy group, cyclohexyloxy group, etc.), amino group (eg, amino group, ethylamino group, dimethylamino group, butylamino group, cyclopentylamino group, 2 -Ethylhexylamino group, dodecylamino Group, anilino group, naphthylamino group, 2-pyridylamino group, etc.), arylalkyl group (benzyl group, phenethyl group, diphenylmethyl group, 1,1-diphenylethyl group, 1,2-diphenylethyl group, etc.), aryl group (For example, phenyl group, p-chlorophenyl group, mesityl group, tolyl group, xylyl group, naphthyl group, anthryl group, azulenyl group, acenaphthenyl group, fluorenyl group, phenanthryl group, indenyl group, pyrenyl group, biphenylyl group, etc.), hetero An aryl group (for example, pyridyl group, pyrimidinyl group, furyl group, pyrrolyl group, imidazolyl group, benzoimidazolyl group, pyrazolyl group, pyrazinyl group, triazolyl group (for example, 1,2,4-triazol-1-yl group, 1,2 , 3-triazol-1-yl group, etc.), oxazolyl group, Nzooxazolyl, thiazolyl, isoxazolyl, isothiazolyl, furazanyl, thienyl, quinolyl, benzofuryl, dibenzofuryl, benzothienyl, dibenzothienyl, indolyl, carbazolyl, carbolinyl, diazacarbazolyl A group (in which one of the carbon atoms constituting the carboline ring of the previous carbolinyl group is replaced by a nitrogen atom), a quinoxalinyl group, a pyridazinyl group, a triazinyl group, a quinazolinyl group, a phthalazinyl group, etc.), an aryloxy group (for example, phenoxy Group, p-chlorophenoxy group, mesityloxy group, tolyloxy group, xylyloxy group, naphthyloxy group, anthryloxy group, azulenyloxy group, acenaphthenyloxy group, fluorenyloxy group, phenanthryloxy group Si group, indenyloxy group, pyrenyloxy group, biphenylyloxy group, etc.), heteroaryloxy group (for example, pyridyloxy group, pyrimidinyloxy group, furyloxy group, pyrrolyloxy group, imidazolyloxy group, benzoimidazolyloxy group) , Pyrazolyloxy group, pyrazinyloxy group, triazolyloxy group (for example, 1,2,4-triazol-1-yloxy group, 1,2,3-triazol-1-yloxy group, etc.), oxazolyloxy group, benzo Oxazolyloxy, thiazolyloxy, isoxazolyloxy, isothiazolyloxy, furazanyloxy, thienyloxy, quinolyloxy, benzofuryloxy, dibenzofuryloxy, benzothienyloxy, dibenzothienyloxy , Indolyloxy group, carbazolyloxy group, carbolinyloxy group, etc.), non-aromatic hydrocarbon ring group (for example, 1,2,3,4-tetrahydronaphthalen-5-yl group, 9,9, 10,10-tetramethyl-9,10-dihydroanthracen-2-yl group, biphenylene-1-yl group, etc., or non-aromatic heterocyclic group (eg pyrrolidyl group, imidazolidyl group, oxazolidyl group, morpholyl group, thiomorpholinyl) Group, tetrahydrofuran-2-yl group, 10H-phenoxazin-3-yl group, phenoxathiin-3-yl group, chroman-2-one-6-yl group, 2,3,4,9-tetrahydro- 1H-carbazol-7-yl group and the like.

  V11, V12, and V13 are preferably a single bond,> CH2 group,> CHR 'group,> CR'R "group, or> NR group.

In the general formula (1) or (2), the linking groups V1, V2, and V3 are bonded to any of CyD1, CyC1, CyD2, CyC2, CyD3, and CyC3 constituting the bidentate ligands L1, L2, and L3, respectively. Alternatively, it may be bonded to only one of the two rings constituting each bidentate ligand L1, L2, or L3, or may be bonded to one of both of the two rings.
Specific binding modes of L1, L2, L3 and V1, V2, V3 constituting the hexadentate ligand (Lig) are as follows.

Preferred as the bonding mode of L1, L2, L3 and V1, V2, V3 constituting the hexadentate ligand (Lig) are the general formulas (A) to (F), (G), (K), (L ), (M), (O), (Q), (S) to (AA), (AD) to (AJ).
More preferably, the general formulas (A), (B), (D), (E), (G), (K), (O), (T), (X), (Z), (AE), (AG).
More preferably, they are general formula (A), (B), (O), (T), (X), (Z), (AE), (AG).

  In the hexadentate ligand, the linking groups V1, V2, and V3 are not conjugated with each aromatic ring with respect to CyD1, CyC1, CyD2, CyC2, CyD3, and CyC3 constituting the bidentate ligands L1, L2, and L3. Bonding is preferably via an aromatic ring substituent.

  Preferred structures as the bidentate ligands L1, L2, and L3 according to the present invention are the structures shown below.

In general formula (4) and general formula (5), ring A, ring B, ring C, ring D and ring E represent a 5-membered or 6-membered aromatic hydrocarbon ring or aromatic heterocycle, and X1, X2 And X3 represents a carbon atom or a nitrogen atom.
The 6-membered aromatic hydrocarbon ring is a benzene ring, the 5-membered aromatic heterocycle is a 6-membered aromatic heterocycle such as a furan ring, a thiophene ring, an oxazole ring, a pyrrole ring, an imidazole ring, an oxazole ring, or a thiazole ring. Examples thereof include a pyridine ring, a pyridazine ring, a pyrimidine ring, a pyrazine ring, and a triazine ring.

Cy represents a 5- or 6-membered aromatic hydrocarbon ring, aromatic heterocycle, non-aromatic hydrocarbon ring or non-aromatic heterocycle, and n0 represents 0 or 1.
The 6-membered aromatic hydrocarbon ring is a benzene ring, the 5-membered aromatic heterocycle is an oxazole ring, thiazole ring, oxadiazole ring, oxatriazole ring, isoxazole ring, tetrazole ring, thiadiazole ring, thiatriazole ring, 6-membered aromatic heterocycles such as isothiazole ring, thiophene ring, furan ring, pyrrole ring, imidazole ring, pyrazole ring, triazole ring, tetrazole ring, pyridine ring, pyridazine ring, pyrimidine ring, pyrazine ring, triazine ring, etc. The 5-membered non-aromatic hydrocarbon ring includes cyclopentane ring and cyclopentene ring, and the 6-membered non-aromatic hydrocarbon ring includes cyclohexane ring, cyclohexene ring, 1,2,3,4-tetrahydronaphthalene ring, 9,9 , 10,10-Tetramethyl-9,10-dihydroanthracene, biphenylene, etc. Examples of aromatic heterocycles include pyrrolidine, imidazolidine, and oxazolidine rings, and six-membered non-aromatic heterocycles include piperidine, piperazine, morpholyl, thiomorpholine, tetrahydrofuran, 10H-phenoxazine, and phenoxathi. In ring, chroman-2-one ring, 2,3,4,9-tetrahydro-1H-carbazole ring, and the like.

  R1, R2, R3 and R4 each independently represents a hydrogen atom, a halogen atom or a cyano group, or an optionally substituted alkyl group (for example, a methyl group, ethyl group, propyl group, isopropyl group, tert- Butyl group, 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) Etc.), alkynyl groups (eg ethynyl group, propargyl group etc.), alkoxy groups (eg methoxy group, ethoxy group, propyloxy group, pentyloxy group, hexyloxy group, octyloxy group, dodecyloxy group etc.), cyclo An alkyloxy group (for example, a cyclopentyloxy group, Cyclohexyloxy group, etc.), amino group (for example, amino group, ethylamino group, dimethylamino group, butylamino group, cyclopentylamino group, 2-ethylhexylamino group, dodecylamino group, anilino group, naphthylamino group, 2- Pyridylamino group, etc.), silyl groups (eg, trimethylsilyl group, triisopropylsilyl group, triphenylsilyl group, phenyldiethylsilyl group, etc.), arylalkyl groups (benzyl group, phenethyl group, diphenylmethyl group, 1,1-diphenylethyl) Group, 1,2-diphenylethyl group, etc.), aryl group (for example, phenyl group, p-chlorophenyl group, mesityl group, tolyl group, xylyl group, naphthyl group, anthryl group, azulenyl group, acenaphthenyl group, fluorenyl group, phenanthryl) Group, indenyl group, pyrenyl Group, biphenylyl group, etc.), heteroaryl group (for example, pyridyl group, pyrimidinyl group, furyl group, pyrrolyl group, imidazolyl group, benzoimidazolyl group, pyrazolyl group, pyrazinyl group, triazolyl group (for example, 1,2,4-triazole- 1-yl group, 1,2,3-triazol-1-yl group, etc.), oxazolyl group, benzoxazolyl group, thiazolyl group, isoxazolyl group, isothiazolyl group, furazanyl group, thienyl group, quinolyl group, benzofuryl group, Dibenzofuryl group, benzothienyl group, dibenzothienyl group, indolyl group, carbazolyl group, carbolinyl group, diazacarbazolyl group (in which one of the carbon atoms constituting the carboline ring of the previous carbolinyl group is replaced by a nitrogen atom) ), Quinoxalinyl, pyridazinyl, Azinyl, quinazolinyl, phthalazinyl, etc.), aryloxy groups (for example, phenoxy, p-chlorophenoxy, mesityloxy, tolyloxy, xylyloxy, naphthyloxy, anthryloxy, azulenyloxy, acenaphthenyl) Oxy group, fluorenyloxy group, phenanthryloxy group, indenyloxy group, pyrenyloxy group, biphenylyloxy group, etc.), heteroaryloxy group (for example, pyridyloxy group, pyrimidinyloxy group, furyloxy) Group, pyrrolyloxy group, imidazolyloxy group, benzoimidazolyloxy group, pyrazolyloxy group, pyrazinyloxy group, triazolyloxy group (for example, 1,2,4-triazol-1-yloxy group, 1,2,3-triazole-1) Yloxy group, etc.), oxazolyloxy group, benzoxazolyloxy group, thiazolyloxy group, isoxazolyloxy group, isothiazolyloxy group, furazanyloxy group, thienyloxy group, quinolyloxy group, benzofuryloxy group, dibenzo Furyloxy group, benzothienyloxy group, dibenzothienyloxy group, indolyloxy group, carbazolyloxy group, carbolinyloxy group, etc.), non-aromatic hydrocarbon ring group (eg 1,2,3,4) -Tetrahydronaphthalen-5-yl group, 9,9,10,10-tetramethyl-9,10-dihydroanthracen-2-yl group, biphenylene-1-yl group etc.) or non-aromatic heterocyclic group (eg pyrrolidyl) Group, imidazolidyl group, oxazolidyl group, morpholyl group, thiomorpholinyl group, tetrahydrofuran-2-yl group, 10H-phenoxazine-3- Yl group, phenoxathiin-3-yl group, chroman-2-one-6-yl group, 2,3,4,9-tetrahydro-1H-carbazol-7-yl group).

  Ra, Rb, Rc and Rd are each independently a hydrogen atom, a halogen atom or a cyano group, or an optionally substituted alkyl group (for example, a methyl group, an ethyl group, a propyl group, an isopropyl group, a tert-butyl group, Pentyl group, hexyl group, octyl group, dodecyl group, tridecyl group, tetradecyl group, pentadecyl group, etc.), cycloalkyl group (for example, cyclopentyl group, cyclohexyl group, etc.), alkenyl group (for example, vinyl group, allyl group, etc.), Alkynyl group (for example, ethynyl group, propargyl group, etc.), alkoxy group (for example, methoxy group, ethoxy group, propyloxy group, pentyloxy group, hexyloxy group, octyloxy group, dodecyloxy group, etc.), cycloalkyloxy group (For example, cyclopentyloxy group, cyclohexane Siloxy group, etc.), amino group (for example, amino group, ethylamino group, dimethylamino group, butylamino group, cyclopentylamino group, 2-ethylhexylamino group, dodecylamino group, anilino group, naphthylamino group, 2-pyridylamino group) ), Silyl groups (for example, trimethylsilyl group, triisopropylsilyl group, triphenylsilyl group, phenyldiethylsilyl group, etc.), arylalkyl groups (benzyl group, phenethyl group, diphenylmethyl group, 1,1-diphenylethyl group, 1,2-diphenylethyl group), aryl group (for example, phenyl group, p-chlorophenyl group, mesityl group, tolyl group, xylyl group, naphthyl group, anthryl group, azulenyl group, acenaphthenyl group, fluorenyl group, phenanthryl group, Indenyl, pyrenyl, bif Enylyl group, etc.), heteroaryl group (for example, pyridyl group, pyrimidinyl group, furyl group, pyrrolyl group, imidazolyl group, benzimidazolyl group, pyrazolyl group, pyrazinyl group, triazolyl group (for example, 1,2,4-triazole-1- Yl, 1,2,3-triazol-1-yl, etc.), oxazolyl, benzoxazolyl, thiazolyl, isoxazolyl, isothiazolyl, furazanyl, thienyl, quinolyl, benzofuryl, dibenzofuryl Group, benzothienyl group, dibenzothienyl group, indolyl group, carbazolyl group, carbolinyl group, diazacarbazolyl group (indicating that one of the carbon atoms constituting the carboline ring of the previous carbolinyl group is replaced by a nitrogen atom), Quinoxalinyl group, pyridazinyl group, triazini Group, quinazolinyl group, phthalazinyl group, etc.), aryloxy group (for example, phenoxy group, p-chlorophenoxy group, mesityloxy group, tolyloxy group, xylyloxy group, naphthyloxy group, anthryloxy group, azulenyloxy group, acenaphthenyloxy group) Group, fluorenyloxy group, phenanthryloxy group, indenyloxy group, pyrenyloxy group, biphenylyloxy group, etc.), heteroaryloxy group (for example, pyridyloxy group, pyrimidinyloxy group, furyloxy group) Pyrrolyloxy group, imidazolyloxy group, benzoimidazolyloxy group, pyrazolyloxy group, pyrazinyloxy group, triazolyloxy group (for example, 1,2,4-triazol-1-yloxy group, 1,2,3-triazol-1-ylo Oxazolyloxy group, benzoxazolyloxy group, thiazolyloxy group, isoxazolyloxy group, isothiazolyloxy group, furazanyloxy group, thienyloxy group, quinolyloxy group, benzofuryloxy group, dibenzo Furyloxy group, benzothienyloxy group, dibenzothienyloxy group, indolyloxy group, carbazolyloxy group, carbolinyloxy group, etc.), non-aromatic hydrocarbon ring group (eg 1,2,3,4) -Tetrahydronaphthalen-5-yl group, 9,9,10,10-tetramethyl-9,10-dihydroanthracen-2-yl group, biphenylene-1-yl group etc.) or non-aromatic heterocyclic group (eg pyrrolidyl) Group, imidazolidyl group, oxazolidyl group, morpholyl group, thiomorpholinyl group, tetrahydrofuran-2-yl group, 10H-phenoxazin-3-yl group, Phenoxathiin-3-yl group, chroman-2-one-6-yl group, 2,3,4,9-tetrahydro-1H-carbazol-7-yl group).

na, nb, nc and nd represent an integer of 1 to 3, and nc preferably represents 1 or 2.
A plurality of Ra, Rb, Rc and Rd may be the same as or different from each other.
Ra and ring A, Rb and ring B, Rc and ring C, Rd and ring D, and Ra and ring E may be bonded at two positions to form a condensed ring.
n1 and n2 represent 0 or 1, and n1 + n2> 1.

V10 represents a linking group or a single bond.
When V10 is a linking group, the linking group is> CH2 group,> CHR 'group,>CR'R"group,>SiR'R"group,> BR group,> NR group,> PR group, -O- Group, -S- group,> C = O group.
Here, R is an optionally substituted alkyl group (for example, methyl group, ethyl group, propyl group, isopropyl group, tert-butyl group, pentyl group, hexyl group, octyl group, dodecyl group, tridecyl group, tetradecyl group). Group, pentadecyl group, etc.), cycloalkyl group (eg, cyclopentyl group, cyclohexyl group, etc.), arylalkyl group (benzyl group, phenethyl group, diphenylmethyl group, 1,1-diphenylethyl group, 1,2-diphenylethyl group) Etc.), aryl group (for example, phenyl group, p-chlorophenyl group, mesityl group, tolyl group, xylyl group, naphthyl group, anthryl group, azulenyl group, acenaphthenyl group, fluorenyl group, phenanthryl group, indenyl group, pyrenyl group, biphenylyl Group), heteroaryl group (for example, pyridyl group) Pyrimidinyl group, furyl group, pyrrolyl group, imidazolyl group, benzimidazolyl group, pyrazolyl group, pyrazinyl group, triazolyl group (for example, 1,2,4-triazol-1-yl group, 1,2,3-triazol-1-yl group) Group), oxazolyl group, benzoxazolyl group, thiazolyl group, isoxazolyl group, isothiazolyl group, furazanyl group, thienyl group, quinolyl group, benzofuryl group, dibenzofuryl group, benzothienyl group, dibenzothienyl group, indolyl group, carbazolyl Group, carbolinyl group, diazacarbazolyl group (in which one of the carbon atoms constituting the carboline ring of the previous carbolinyl group is replaced by a nitrogen atom), quinoxalinyl group, pyridazinyl group, triazinyl group, quinazolinyl group, phthalazinyl group Etc.), non-aromatic carbonization Hydrogen ring group (for example, 1,2,3,4-tetrahydronaphthalen-5-yl group, 9,9,10,10-tetramethyl-9,10-dihydroanthracen-2-yl group, biphenylene-1-yl group) Or non-aromatic heterocyclic group (for example, pyrrolidyl group, imidazolidyl group, oxazolidyl group, morpholyl group, thiomorpholinyl group, tetrahydrofuran-2-yl group, 10H-phenoxazin-3-yl group, phenoxathiin-3 -Yl group, chroman-2-one-6-yl group, 2,3,4,9-tetrahydro-1H-carbazol-7-yl group and the like.
R ′ and R ″ are each independently an optionally substituted alkyl group (for example, methyl group, ethyl group, propyl group, isopropyl group, tert-butyl group, pentyl group, hexyl group, octyl group, dodecyl group, Tridecyl group, tetradecyl group, pentadecyl group, etc.), cycloalkyl group (eg, cyclopentyl group, cyclohexyl group, etc.), alkoxy group (eg, methoxy group, ethoxy group, propyloxy group, pentyloxy group, hexyloxy group, octyloxy group) Group, dodecyloxy group, etc.), cycloalkyloxy group (eg, cyclopentyloxy group, cyclohexyloxy group, etc.), amino group (eg, amino group, ethylamino group, dimethylamino group, butylamino group, cyclopentylamino group, 2 -Ethylhexylamino group, dodecyla Mino group, anilino group, naphthylamino group, 2-pyridylamino group, etc.), arylalkyl group (benzyl group, phenethyl group, diphenylmethyl group, 1,1-diphenylethyl group, 1,2-diphenylethyl group, etc.), aryl Groups (for example, phenyl group, p-chlorophenyl group, mesityl group, tolyl group, xylyl group, naphthyl group, anthryl group, azulenyl group, acenaphthenyl group, fluorenyl group, phenanthryl group, indenyl group, pyrenyl group, biphenylyl group, etc.), A heteroaryl group (for example, pyridyl group, pyrimidinyl group, furyl group, pyrrolyl group, imidazolyl group, benzoimidazolyl group, pyrazolyl group, pyrazinyl group, triazolyl group (for example, 1,2,4-triazol-1-yl group, 1, 2,3-triazol-1-yl group), oxazolyl , Benzoxazolyl, thiazolyl, isoxazolyl, isothiazolyl, furazanyl, thienyl, quinolyl, benzofuryl, dibenzofuryl, benzothienyl, dibenzothienyl, indolyl, carbazolyl, carbolinyl, dia Zacarbazolyl group (indicating that one of the carbon atoms constituting the carboline ring of the previous carbolinyl group is replaced by a nitrogen atom), quinoxalinyl group, pyridazinyl group, triazinyl group, quinazolinyl group, phthalazinyl group, etc.), aryloxy group (For example, phenoxy group, p-chlorophenoxy group, mesityloxy group, tolyloxy group, xylyloxy group, naphthyloxy group, anthryloxy group, azulenyloxy group, acenaphthenyloxy group, fluorenyloxy group, phenanthryl Oxy group, indenyloxy group, pyrenyloxy group, biphenylyloxy group, etc.), heteroaryloxy group (for example, pyridyloxy group, pyrimidinyloxy group, furyloxy group, pyrrolyloxy group, imidazolyloxy group, benzimidazolyloxy group) , Pyrazolyloxy group, pyrazinyloxy group, triazolyloxy group (for example, 1,2,4-triazol-1-yloxy group, 1,2,3-triazol-1-yloxy group, etc.), oxazolyloxy group, benzo Oxazolyloxy, thiazolyloxy, isoxazolyloxy, isothiazolyloxy, furazanyloxy, thienyloxy, quinolyloxy, benzofuryloxy, dibenzofuryloxy, benzothienyloxy, dibenzothienyl Si group, indolyloxy group, carbazolyloxy group, carbolinyloxy group, etc.), non-aromatic hydrocarbon ring group (for example, 1,2,3,4-tetrahydronaphthalen-5-yl group, 9, 9,10,10-tetramethyl-9,10-dihydroanthracen-2-yl group, biphenylene-1-yl group, etc., or non-aromatic heterocyclic group (eg pyrrolidyl group, imidazolidyl group, oxazolidyl group, morpholyl group) Thiomorpholinyl group, tetrahydrofuran-2-yl group, 10H-phenoxazin-3-yl group, phenoxathiin-3-yl group, chroman-2-one-6-yl group, 2,3,4,9- A tetrahydro-1H-carbazol-7-yl group and the like.
V10 is preferably a single bond,> CH2 group,> CHR 'group,>CR'R"groupor> NR group.
The linking groups V1, V2, and V3 are bonded to the bidentate ligands L1, L2, and L3 as any two selected from R1 to R4.

  Preferred as the bidentate ligands L1, L2, and L3 according to the present invention are ligand compounds having a partial structure represented by the general formula (4-1) or (5-1).

In general formula (4-1) and general formula (5-1), ring A, ring B, ring C, ring D and ring E represent a 5-membered or 6-membered aromatic hydrocarbon ring or aromatic heterocycle. , X1, X2 and X3 represent a carbon atom or a nitrogen atom.
Cy represents a 5- or 6-membered aromatic hydrocarbon ring, aromatic heterocycle, non-aromatic hydrocarbon ring or non-aromatic heterocycle, and n0 represents 0 or 1.

R1, R2, R3 and R4 each independently represents a hydrogen atom, a halogen atom or a cyano group, or an optionally substituted alkyl group, cycloalkyl group, alkenyl group, alkynyl group, alkoxy group, cycloalkyloxy Represents a group, amino group, silyl group, arylalkyl group, aryl group, heteroaryl group, aryloxy group, heteroaryloxy group, non-aromatic hydrocarbon ring group or non-aromatic heterocyclic group.
Ra, Rb, Rc and Rd each independently represents a hydrogen atom, a halogen atom or a cyano group, or an optionally substituted alkyl group, cycloalkyl group, alkenyl group, alkynyl group, alkoxy group, amino group, A silyl group, an arylalkyl group, an aryl group, a heteroaryl group, an aryloxy group, a heteroaryloxy group, a non-aromatic hydrocarbon ring group, or a non-aromatic heterocyclic group is represented.
na, nb, nc and nd represent an integer of 1 to 3, and nc preferably represents 1 or 2.
A plurality of Ra, Rb, Rc and Rd may be the same as or different from each other.
Ra and ring A, Rb and ring B, Rc and ring C, Rd and ring D, and Ra and ring E may be bonded at two positions to form a condensed ring.
n1 and n2 represent 0 or 1, and n1 + n2> 1.
The linking groups V1, V2, and V3 are bonded to the bidentate ligands L1, L2, and L3 as any two selected from R1 to R4.

  In general formula (4-1) and general formula (5-1), regarding ring A, ring B, ring C, ring D, ring E, Cy, R1, R2, R3, R4, Ra, Rb, Rc, Rd The detailed description is the same as in the description of the general formulas (4) and (5).

  More preferred as the bidentate ligands L1, L2, and L3 according to the present invention are ligand compounds having a partial structure represented by the general formula (4-2) or (5-2).

In general formulas (4-2) and (5-2), ring B, ring C and ring D represent a 5-membered or 6-membered aromatic hydrocarbon ring or aromatic heterocycle, and X1, X2, X3 , X4 and X5 represent a carbon atom or a nitrogen atom.
Cy represents a 5- or 6-membered aromatic hydrocarbon ring, aromatic heterocycle, non-aromatic hydrocarbon ring or non-aromatic heterocycle, and n0 represents 0 or 1.
R1, R2, R3 and R4 each independently represents a hydrogen atom, a halogen atom or a cyano group, or an optionally substituted alkyl group, cycloalkyl group, alkenyl group, alkynyl group, alkoxy group, cycloalkyloxy Represents a group, amino group, silyl group, arylalkyl group, aryl group, heteroaryl group, aryloxy group, heteroaryloxy group, non-aromatic hydrocarbon ring group or non-aromatic heterocyclic group.

Ra, Rb, Rc and Rd each independently represents a hydrogen atom, a halogen atom or a cyano group, or an optionally substituted alkyl group, cycloalkyl group, alkenyl group, alkynyl group, alkoxy group, amino group, A silyl group, an arylalkyl group, an aryl group, a heteroaryl group, an aryloxy group, a heteroaryloxy group, a non-aromatic hydrocarbon ring group or a non-aromatic heterocyclic group is represented.
Re represents an alkyl group which may be substituted (for example, methyl group, ethyl group, propyl group, isopropyl group, tert-butyl group, pentyl group, hexyl group, octyl group, dodecyl group, tridecyl group, tetradecyl group, pentadecyl group). Group), cycloalkyl group (eg, cyclopentyl group, cyclohexyl group, etc.), alkenyl group (eg, vinyl group, allyl group, etc.), alkynyl group (eg, ethynyl group, propargyl group, etc.), alkoxy group (eg, methoxy) Group, ethoxy group, propyloxy group, pentyloxy group, hexyloxy group, octyloxy group, dodecyloxy group, etc.), cycloalkyloxy group (for example, cyclopentyloxy group, cyclohexyloxy group, etc.), amino group (for example, amino Group, ethylamino group, dimethylamino group, Tylamino group, cyclopentylamino group, 2-ethylhexylamino group, dodecylamino group, anilino group, naphthylamino group, 2-pyridylamino group, etc., silyl group (for example, trimethylsilyl group, triisopropylsilyl group, triphenylsilyl group, phenyl) Diethylsilyl group, etc.), arylalkyl groups (benzyl group, phenethyl group, diphenylmethyl group, 1,1-diphenylethyl group, 1,2-diphenylethyl group, etc.), aryl groups (eg, phenyl group, p-chlorophenyl group) , Mesityl group, tolyl group, xylyl group, xylyl group, anthryl group, azulenyl group, acenaphthenyl group, fluorenyl group, phenanthryl group, indenyl group, pyrenyl group, biphenylyl group, etc.), heteroaryl group (for example, pyridyl group, pyrimidinyl group) , Furyl group, pi Loryl group, imidazolyl group, benzoimidazolyl group, pyrazolyl group, pyrazinyl group, triazolyl group (for example, 1,2,4-triazol-1-yl group, 1,2,3-triazol-1-yl group, etc.), oxazolyl group , Benzoxazolyl, thiazolyl, isoxazolyl, isothiazolyl, furazanyl, thienyl, quinolyl, benzofuryl, dibenzofuryl, benzothienyl, dibenzothienyl, indolyl, carbazolyl, carbolinyl, dia Zacarbazolyl group (indicating that one of the carbon atoms constituting the carboline ring of the previous carbolinyl group is replaced by a nitrogen atom), quinoxalinyl group, pyridazinyl group, triazinyl group, quinazolinyl group, phthalazinyl group, etc.), aryloxy group (For example, phenoxy group, -Chlorophenoxy, mesityloxy, tolyloxy, xylyloxy, naphthyloxy, anthryloxy, azulenyloxy, acenaphthenyloxy, fluorenyloxy, phenanthryloxy, indenyloxy, pyrenyloxy Group, biphenylyloxy group, etc.), heteroaryloxy group (for example, pyridyloxy group, pyrimidinyloxy group, furyloxy group, pyrrolyloxy group, imidazolyloxy group, benzoimidazolyloxy group, pyrazolyloxy group, pyrazinyloxy group, triazolyl group) Ruoxy group (for example, 1,2,4-triazol-1-yloxy group, 1,2,3-triazol-1-yloxy group, etc.), oxazolyloxy group, benzoxazolyloxy group, thiazolyloxy group, Soxazolyloxy, isothiazolyloxy, furazanyloxy, thienyloxy, quinolyloxy, benzofuryloxy, dibenzofuryloxy, benzothienyloxy, dibenzothienyloxy, indolyloxy, carbazolyl Luoxy group, carbolinyloxy group, etc.), non-aromatic hydrocarbon ring group (for example, 1,2,3,4-tetrahydronaphthalen-5-yl group, 9,9,10,10-tetramethyl-9 , 10-dihydroanthracen-2-yl group, biphenylene-1-yl group, etc.) or non-aromatic heterocyclic group (eg pyrrolidyl group, imidazolidyl group, oxazolidyl group, morpholyl group, thiomorpholinyl group, tetrahydrofuran-2-yl group) , 10H-phenoxazin-3-yl group, phenoxathiin-3-yl group, chroman-2-one-6-yl group, 2,3,4,9-tetrahydro-1H-carbazole -7-yl group and the like.

na, nb, nc and nd represent an integer of 1 to 3, and nc preferably represents 1 or 2.
A plurality of Ra, Rb, Rc and Rd may be the same as or different from each other.
Ra and a ring connected thereto, Rb and a ring B, Rc and a ring C, Rd and a ring D, Re and a ring connected to it may be bonded at two positions to form a condensed ring.
n1 and n2 represent 0 or 1, and n1 + n2> 1.
The linking groups V1, V2, and V3 are bonded to the bidentate ligands L1, L2, and L3 as any two selected from R1 to R4.

  In the general formula (4-2) and the general formula (5-2), the detailed description regarding the ring B, the ring C, the ring D, Cy, R1, R2, R3, R4, Ra, Rb, Rc, and Rd is the general formula. This is the same as that described in (4) and (5).

  Particularly preferred as the bidentate ligands L1, L2, and L3 according to the present invention are ligand compounds having a partial structure represented by the general formula (4-3) or (5-3).

In general formulas (4-3) and (5-3), ring B, ring C and ring D represent a 5- or 6-membered aromatic hydrocarbon ring or aromatic heterocycle, and X1 represents CH or N Represents.
Cy represents a 5- or 6-membered aromatic hydrocarbon ring, aromatic heterocycle, non-aromatic hydrocarbon ring or non-aromatic heterocycle, and n0 represents 0 or 1.
R1, R2, R3 and R4 each independently represents a hydrogen atom, a halogen atom or a cyano group, or an optionally substituted alkyl group, cycloalkyl group, alkenyl group, alkynyl group, alkoxy group, cycloalkyloxy Represents a group, amino group, silyl group, arylalkyl group, aryl group, heteroaryl group, aryloxy group, heteroaryloxy group, non-aromatic hydrocarbon ring group or non-aromatic heterocyclic group.
Ra, Rb, Rc and Rd each independently represents a hydrogen atom, a halogen atom or a cyano group, or an optionally substituted alkyl group, cycloalkyl group, alkenyl group, alkynyl group, alkoxy group, amino group, A silyl group, an arylalkyl group, an aryl group, a heteroaryl group, an aryloxy group, a heteroaryloxy group, a non-aromatic hydrocarbon ring group, or a non-aromatic heterocyclic group is represented.
Re represents an optionally substituted alkyl group, cycloalkyl group, alkenyl group, alkynyl group, arylalkyl group, aryl group, heteroaryl group, non-aromatic hydrocarbon ring group or non-aromatic heterocyclic group.
na, nb, nc and nd represent an integer of 1 to 3, and nc preferably represents 1 or 2.
A plurality of Ra, Rb, Rc and Rd may be the same as or different from each other.
Ra and a ring connected thereto, Rb and a ring B, Rc and a ring C, Rd and a ring D, Re and a ring connected to it may be bonded at two positions to form a condensed ring.
n2 represents 0 or 1.
The linking groups V1, V2, and V3 are bonded to the bidentate ligands L1, L2, and L3 as any two selected from R1 to R4. ]

  In the general formula (4-3) and the general formula (5-3), the detailed explanation about ring B, ring C, ring D, Cy, R1, R2, R3, R4, Ra, Rb, Rc, Rd, Re This is the same as in the description of the general formulas (4), (5), (4-2), and (5-2).

  Hereinafter, although the specific example of the iridium ortho metal complex represented by the said General formula (1) based on this invention is shown, this invention is not limited to these.

  These metal complexes are described in, for example, Organic Letter, vol. 16, 2579-2581 (2001), Inorganic Chemistry, Vol. 30, No. 8, 1685-1687 (1991), J. Am. Am. Chem. Soc. , 123, 4304 (2001), Inorganic Chemistry, Vol. 40, No. 7, 1704-1711 (2001), Inorganic Chemistry, Vol. 41, No. 12, 3055-3066 (2002) , New Journal of Chemistry. 26, 1171 (2002), Organic Letter, vol. 3, pages 415 to 418 (2006), and further by applying methods such as references described in these documents.

  Although the synthesis example of the typical compound of the metal complex based on this invention is shown below, this invention is not limited to these.

(1) Synthesis of complex A-1

  Under a nitrogen atmosphere, 850 mg of ligand A-1 (0.50 mmol) and 250 mg of trisacetylacetonatoiridium (0.51 mmol) were suspended in 30 ml of ethylene glycol. The reaction was carried out at reflux temperature for 48 hours under a nitrogen atmosphere. The reaction solution was cooled, 30 ml of methanol was added, and the precipitated crystals were collected by filtration. The obtained crystals were further washed with methanol and dried to obtain 710 mg (yield 75%) of a crude product. This crude product was purified by column gel chromatography (hexane-tetrahydrofuran = 10: 1 to 4: 1) to obtain 610 mg (yield 65%) of complex A-1.

It was confirmed by MASS and 1H-NMR that the purified compound was the target product.
1H-NMR (400 MHz, deuterated tetrahydrofuran)
(Chemical shift δ, peak shape, proton number)
: Δ = 0.98 (d, 9H, CH3-),
1.03 (d, 9H, CH3-),
1.11 (d, 9H, CH3-),
1.29 (d, 9H, CH3-),
1.90-2.90 (m, 30H,> CH2),
2.93 (m, 3H,> CH-),
6.00 (d, 3H,> CH of imidazole ring)
6.31 (d, 3H,> CH of benzene ring),
6.80 (m, 6H,> CH of benzene ring),
6.86 (m, 3H,> CH of benzene ring),
6.92 (m, 3H,> CH of benzene ring),
6.95 (d, 3H,> CH of imidazole ring)
7.08 (s, 3H,> CH of benzene ring),
7.30 (m, 3H,> CH of benzene ring),
7.35 to 7.45 (m, 18H,> CH of benzene group)

  The PL (photoluminescence) emission maximum wavelength in the solution of Exemplified Compound A-1 measured using Hitachi F-4500 is 466 nm (T = 77 K in 2-methyltetrahydrofuran), 475 nm (room temperature in methylene chloride). Met.

(2) Synthesis of complex B-1

  Under a nitrogen atmosphere, 590 mg (0.50 mmol) of ligand B-1 and 250 mg (0.51 mmol) of trisacetylacetonatoiridium were suspended in 30 ml of ethylene glycol. The reaction was carried out at reflux temperature for 48 hours under a nitrogen atmosphere. The reaction solution was cooled, 30 ml of methanol was added, and the precipitated crystals were collected by filtration. The obtained crystals were further washed with methanol, and after drying, a yield of 530 mg (yield 78%) was obtained. This crude product was purified by column gel chromatography (hexane-tetrahydrofuran = 10: 1 to 4: 1) to obtain 480 mg (yield 70%) of complex B-1.

It was confirmed by MASS and 1H-NMR that the purified compound was the target product.
1H-NMR (400 MHz, deuterated tetrahydrofuran)
(Chemical shift δ, peak shape, proton number)
: Δ = 1.90-2.90 (m, 42H,> CH2),
6.03 (d, 3H,> CH of imidazole ring)
6.32 (d, 3H,> CH of benzene ring),
6.78 (m, 6H,> CH of benzene ring),
6.85 (m, 3H,> CH of benzene ring),
6.90 (m, 3H,> CH of benzene ring),
6.94 (d, 3H,> CH of imidazole ring)
7.06 (s, 3H,> CH of benzene ring),
7.25 (m, 3H,> CH of benzene ring),
7.30-7.45 (m, 9H,> CH of benzene group)

  The PL emission maximum wavelength in the solution of Exemplified Compound B-1 measured using Hitachi F-4500 was 465 nm (T = 77 K, in 2-methyltetrahydrofuran) and 474 nm (room temperature, in methylene chloride).

  Other compounds of the present invention can also be synthesized with good yield by using the same synthesis method as in the above synthesis examples and using appropriate raw materials.

<< Constituent layers of organic EL elements >>
The constituent layers of the organic EL element of the present invention will be described.
In this invention, although the preferable specific example of the layer structure of an organic EL element is shown below, this invention is not limited to these.

(I) Anode / light emitting layer / electron transport layer / cathode (ii) Anode / hole transport layer / light emitting layer / electron transport layer / cathode (iii) Anode / hole transport layer / light emitting layer / hole blocking layer / electron Transport layer / cathode (iv) Anode / hole transport layer / light emitting layer / hole blocking layer / electron transport layer / cathode buffer layer / cathode (v) Anode / anode buffer layer / hole transport layer / light emitting layer / hole Blocking layer / electron transport layer / cathode buffer layer / cathode

  In the organic EL device of the present invention, the light emitting maximum wavelength of the blue light emitting layer is preferably 430 nm to 480 nm, the green light emitting layer has a light emitting maximum wavelength of 510 nm to 550 nm, and the red light emitting layer has a light emitting maximum wavelength of 600 nm to 640 nm. A monochromatic light emitting layer in the range is preferable, and a display device using these is preferable. Alternatively, a white light emitting layer may be formed by laminating at least three light emitting layers. Further, a non-light emitting intermediate layer may be provided between the light emitting layers. The organic EL element of the present invention is preferably a white light emitting layer, and is preferably a lighting device using these.

  Each layer which comprises the organic EL element of this invention is demonstrated.

<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 total film thickness of the light emitting layer is not particularly limited, but from the viewpoint of improving the uniformity of the film, preventing unnecessary application of high voltage during light emission, and improving the stability of the emission color with respect to the drive current. It is preferable to adjust in the range of 2 nm to 5 μm, more preferably in the range of 2 nm to 200 nm, and particularly preferably in the range of 10 nm to 20 nm.

  For the production of the light-emitting layer, a light-emitting dopant or a host compound can be formed by a known thinning method such as a vacuum deposition method, a spin coating method, a casting method, an LB method, or an ink jet method.

  The light emitting layer of the organic EL device of the present invention preferably contains a light emitting host compound and at least one kind of light emitting dopant (such as a phosphorescent dopant (also referred to as a phosphorescent dopant) or a fluorescent dopant).

(1) Host compound (also referred to as light-emitting host)
The host compound used in the present invention will be described.

  Here, the host compound in the present invention is a phosphorescent quantum yield of phosphorescence emission at a room temperature (25 ° C.) having a mass ratio of 20% or more in the compound contained in the light emitting layer. 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, known host compounds may be used alone or in combination of two or more. By using a plurality of types of host compounds, it is possible to adjust the movement of charges, and the efficiency of the organic EL element can be further increased. Moreover, it becomes possible to mix different light emission by using multiple types of light emission dopants, and, thereby, arbitrary luminescent colors can be obtained.

  The light emitting host used in the present invention may be a low molecular compound or a high molecular compound having a repeating unit, and a low molecular compound having a polymerizable group such as a vinyl group or an epoxy group (evaporation polymerizable light emitting host). Alternatively, one or a plurality of such compounds may be used.

  Although the specific example of the host compound preferably used for this invention below is shown, this invention is not limited to these.

  As a 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 being increased in wavelength, 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.

(2) Luminescent dopant A luminescent dopant is demonstrated.

  As the light-emitting dopant, a fluorescent dopant (also referred to as a fluorescent compound) or a phosphorescent dopant (also referred to as a phosphorescent emitter, a phosphorescent compound, a phosphorescent compound, or the like) can be used, but the emission efficiency is higher. From the viewpoint of obtaining an organic EL device, the light-emitting dopant used in the light-emitting layer or light-emitting unit of the organic EL device of the present invention (sometimes simply referred to as a light-emitting material) contains the above host compound, and at the same time It is preferable to contain a light dopant.

(2.1) Phosphorescent dopant The phosphorescent dopant will be described.

  A phosphorescent dopant 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.). Although defined as being a compound of 01 or more, a preferable phosphorescence quantum yield is 0.1 or more.

  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 dopant according to the present invention achieves the phosphorescence quantum yield (0.01 or more) in any solvent. That's fine.

  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. The energy transfer type that obtains 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 light emission from the phosphorescent dopant is obtained. Although it is a trap type, 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.

  The phosphorescent dopant 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, a platinum compound (platinum complex compound), or a rare earth complex. Of these, iridium compounds are most preferred.

  As a compound used as a phosphorescence dopant, the transition metal complex compound represented by the general formulas (1) to (3) according to the present invention is preferable.

  Moreover, you may use together a conventionally well-known light emission dopant as shown below.

(2.2) Fluorescent dopant (also called fluorescent compound)
Fluorescent dopants (fluorescent compounds) include coumarin dyes, pyran dyes, cyanine dyes, croconium dyes, squalium dyes, oxobenzanthracene dyes, fluorescein dyes, rhodamine dyes, pyrylium dyes, perylene dyes Examples thereof include dyes, stilbene dyes, polythiophene dyes, and rare earth complex phosphors.

  Next, an injection layer, a blocking layer, an electron transport layer and the like used as the constituent layers of the organic EL element of the present invention will be described.

<< Injection layer: electron injection layer, hole injection layer >>
The injection layer is provided as necessary, and there are an electron injection layer and a hole injection layer, and as described above, it exists between the anode and the light emitting layer or the hole transport layer and between the cathode and the light emitting layer or the electron transport layer. May be.

  An injection layer is a layer provided between an electrode and an organic layer in order to reduce drive voltage and improve light emission luminance. “Organic EL element and its forefront of industrialization (issued by NTT Corporation on November 30, 1998) 2), Chapter 2, “Electrode Materials” (pages 123 to 166) in detail, and includes a hole injection layer (anode buffer layer) and an electron injection layer (cathode buffer layer).

  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. Representative phthalocyanine buffer layer, oxide buffer layer typified by vanadium oxide, amorphous carbon buffer layer, polymer buffer layer using conductive polymer such as polyaniline (emeraldine) or polythiophene, tris (2-phenylpyridine) ) Orthometalated complex layers represented by iridium complexes and the like. Further, azatriphenylene derivatives such as those described in JP-T-2003-519432 and JP-A-2006-135145 can also be used as the hole injection material.

  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.

  The hole blocking layer has a function of an electron transport layer in a broad sense, and is made of a hole blocking material that has a function of transporting electrons and has a remarkably small ability to transport holes. The probability of recombination of electrons and holes can be improved by blocking.

  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 of the present invention is preferably provided adjacent to the light emitting layer.

  The hole blocking layer contains the carbazole derivative, carboline derivative, or diazacarbazole derivative (shown in which any one of the carbon atoms constituting the carboline ring of the carboline derivative is replaced by a nitrogen atom). It is preferable to contain.

  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 anode. 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 larger 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 electrons while transporting holes. By blocking, the recombination probability of electrons and holes can be improved.

  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 transport layer according to the present invention is preferably 3 nm to 100 nm, and more preferably 5 nm to 30 nm.

《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 one 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. Further, azatriphenylene derivatives such as those described in JP-T-2003-519432 and JP-A-2006-135145 can also be used as the hole transport material.

  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. In addition, cyclometalated complexes and orthometalated complexes represented by copper phthalocyanine, tris (2-phenylpyridine) iridium complex, and the like can also be used as 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. Although there is no restriction | limiting in particular about the film thickness of a positive hole transport layer, Usually, 5 nm-about 5 micrometers, Preferably it is 5 nm-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 injection layer of the organic EL element of this invention and a positive hole transport layer 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, in the case of a single electron transport layer and a plurality of layers, an electron transport material (also serving as a hole blocking material) used for an electron transport layer adjacent to the light emitting layer on the cathode side is injected from the cathode. Any material may be used as long as it has a function of transferring electrons to the light-emitting layer, and any material known in the art can be selected and used alone or in combination. For example, nitro-substituted fluorene Derivatives, diphenylquinone derivatives, thiopyran dioxide derivatives, carbodiimides, fluorenylidenemethane derivatives, anthraquinodimethane and anthrone derivatives, oxadiazole derivatives, and the like.

  Furthermore, in the above 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.

  Also, 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), etc., and the central metals of these metal complexes are In, Mg, Cu , Ca, Sn, Ga, or Pb can also be used as an 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.

  Further, an electron transport layer having a high n property doped with impurities can also 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 conventionally well-known compound (electron transport material) preferably used 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 electrode substances include metals such as Au, and conductive transparent materials such as CuI, indium tin oxide (ITO), SnO ₂ , and ZnO.

Alternatively, an amorphous material such as IDIXO (In ₂ O ₃ —ZnO) capable of forming a transparent conductive film may be used. For the anode, these electrode materials may be formed into a thin film by a method such as vapor deposition or sputtering, and a pattern having a desired shape may be formed by a photolithography method, or when pattern accuracy is not so high (about 100 μm or more) A pattern may be formed through a mask having a desired shape at the time of vapor deposition or sputtering of the electrode material.

  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, although the film thickness depends on the material, it is usually selected in the range of 10 nm to 1000 nm, preferably 10 nm to 200 nm.

"cathode"
On the other hand, as the cathode, a material having a low 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 (Al ₂ O ₃ ) Mixtures, 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 (Al ₂ O ₃ ) 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 a cathode is preferably several hundred Ω / □ or less, and the film thickness is usually selected in the range of 10 nm to 5 μm, preferably 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 light emission luminance is improved, which is convenient.

  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.

《Support substrate》
As a support substrate (hereinafter also referred to as a substrate, substrate, substrate, support, etc.) that can be used in the organic EL device of the present invention, there is no particular limitation on the type of glass, plastic, etc., and it is transparent. May be opaque. When extracting light from the support substrate side, the support substrate is preferably transparent. Examples of the transparent support substrate preferably used include glass, quartz, and a transparent resin film. A particularly preferable support 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 (25 ± 0.5 ° C.) measured by a method according to JIS K 7129-1992. , Relative humidity (90 ± 2)% RH) is preferably 0.01 g / (m ² · 24 h) or less, and further, oxygen measured by a method according to JIS K 7126-1987. A high barrier film having a permeability of 10 ⁻³ ml / (m ² · 24 h · atm) or less and a water vapor permeability of 10 ⁻⁵ g / (m ² · 24 h) or less is preferable.

  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, sputtering method, reactive sputtering method, molecular beam epitaxy method, cluster ion beam method, ion plating method, plasma polymerization method, atmospheric pressure plasma weight A combination 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 support substrate include metal plates such as aluminum and stainless steel, films, opaque resin substrates, and ceramic substrates.

  The external extraction efficiency at room temperature of light emission of the organic EL device of 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 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 element can be thinned.

Further, 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 · atm) or less, and a method according to JIS K 7129-1992. It is preferable that the water vapor permeability (25 ± 0.5 ° C., relative humidity (90 ± 2)% RH) measured in (1) is 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.

  In addition, it is also preferable that the electrode and the organic layer are coated on the outside of the electrode facing the support substrate with the organic layer interposed therebetween, and an inorganic or organic layer is formed in contact with the support substrate to form a sealing film. . 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. Further, 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 support substrate with the organic 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, and the like 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 inside 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. 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 extracted outside the device, 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 of improving efficiency by providing a light collecting property to a substrate (Japanese Patent Laid-Open No. 63-314795), a method of forming a reflective surface on a side surface of an element (Japanese Patent Laid-Open No. 1-220394), and light emission from a substrate A method of forming an antireflection film by introducing a flat layer having an intermediate refractive index between the bodies (Japanese Patent Laid-Open No. 62-172691), a flat having a lower refractive index between the substrate and the light emitter than the substrate A method of introducing a layer (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) (Japanese Patent Laid-Open No. 11-283951) Gazette).

  In the present invention, these methods can be used in combination with the organic EL device of 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, transparent A method of forming a diffraction grating between any layers of the 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 element having higher luminance or durability.

  When a medium having 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. Further, it is preferably 1.35 or less.

  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.

  As described above, the position where the diffraction grating is introduced may be in any of the layers or in the 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 device of the present invention is processed on the light extraction side of the substrate so as to provide, for example, a microlens array structure, or combined with a so-called condensing sheet, for example, with respect to a specific direction, for example, the device light emitting surface. By condensing in the front direction, the luminance in a specific direction can be increased.

  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.

<< Method for producing organic EL element >>
As an example of the method for producing the organic EL device of the present invention, a method for producing an organic EL device comprising an anode / hole injection layer / hole transport layer / light emitting layer / hole blocking layer / electron transport layer / cathode will be described.

  First, a desired electrode material, for example, a thin film made of an anode material is formed on a suitable substrate so as to have a film thickness of 1 μm or less, preferably 10 nm to 200 nm, to form an anode.

  Next, organic compound thin films such as a hole injection layer, a hole transport layer, a light emitting layer, a hole blocking layer, and an electron transport layer, which are organic EL element materials, are formed thereon.

  As a method for forming each of these layers, there are a vapor deposition method, a wet process (spin coating method, casting method, ink jet method, printing method) and the like as described above, but it is easy to obtain a homogeneous film and it is difficult to generate pinholes. In view of the above, film formation by a coating method such as a spin coating method, an ink jet method, or a printing method is preferable in the present invention.

  Examples of the liquid medium for dissolving or dispersing the organic EL material according to the present invention include ketones such as methyl ethyl ketone and cyclohexanone, fatty acid esters such as ethyl acetate, halogenated hydrocarbons such as dichlorobenzene, toluene, xylene, and mesitylene. Aromatic hydrocarbons such as cyclohexylbenzene, aliphatic hydrocarbons such as cyclohexane, decalin, and dodecane, and organic solvents such as DMF and DMSO can be used. Moreover, as a dispersion method, it can disperse | distribute by dispersion methods, such as an ultrasonic wave, high shear force dispersion | distribution, and media dispersion | distribution.

  After these layers are formed, a thin film made of a cathode material is formed thereon by 1 μm or less, preferably by a method such as vapor deposition or sputtering so that the film thickness is in the range of 50 nm to 200 nm. By providing, a desired organic EL element can be obtained.

  Further, it is also possible to reverse the production order and produce the cathode, the electron transport layer, the hole blocking layer, the light emitting layer, the hole transport layer, the hole injection layer, and the anode in this order. When a DC voltage is applied to the multicolor display device thus obtained, light emission can be observed by applying a voltage of about 2 to 40 V with the positive polarity of the anode and the negative polarity of the cathode. An alternating voltage may be applied. The alternating current waveform to be applied may be arbitrary.

<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 when the result measured with the total CS-1000 (manufactured by Konica Minolta Sensing) is applied to the CIE chromaticity coordinates.

When the organic EL element of the present invention is a white element, white means that the chromaticity in the CIE1931 color system at 1000 cd / m ² is X when the 2 ° viewing angle front luminance is measured by the above method. = 0.33 ± 0.07 and Y = 0.33 ± 0.1.

  EXAMPLES Hereinafter, although an Example demonstrates this invention in detail, this invention is not limited to these. Moreover, the structure of the compound used in an Example is shown below.

<< Preparation of Blue Light-Emitting Organic EL Element 1-1 >>
Transparent support provided with this ITO transparent electrode after patterning on a substrate (NH45 manufactured by NH Techno Glass Co., Ltd.) formed by depositing 100 nm of ITO (indium tin oxide) on a glass substrate of 100 mm × 100 mm × 1.1 mm as an anode The substrate was ultrasonically cleaned with isopropyl alcohol, dried with dry nitrogen gas, and subjected to UV ozone cleaning for 5 minutes.

  This transparent support substrate is fixed to a substrate holder of a commercially available vacuum evaporation apparatus, while 200 mg of the hole injection material 1 is put into a molybdenum resistance heating boat, and 200 mg of the hole transport material 1 is put into another molybdenum resistance heating boat, 200 mg of the host compound (OC-6) is put into another resistance heating boat made of molybdenum, 100 mg of the dopant compound (Comparative Compound 1) is put into another resistance heating boat made of molybdenum, and the electron transport material 1 is put into another resistance heating boat made of molybdenum. And 200 mg of the electron transport material 2 was placed in another molybdenum resistance heating boat and attached to a vacuum deposition apparatus.

Next, the pressure in the vacuum chamber was reduced to 4 × 10 ⁻⁴ Pa, and the heating boat containing the hole injection material 1 was energized and heated, and deposited on a transparent support substrate at a deposition rate of 0.1 nm / second to a thickness of 20 nm. The hole injection layer was provided.

Further, after reducing the vacuum chamber to 4 × 10 ⁻⁴ Pa, the heating boat containing the hole transport material 1 is heated by energization, and deposited on the transparent support substrate at a deposition rate of 0.1 nm / second. A 20 nm thick hole transport layer was provided.

  Furthermore, the hole-transporting layer was heated by energizing the heating boat containing the host compound (OC-6) and the dopant compound (Comparative Compound 1) at a deposition rate of 0.2 nm / second and 0.012 nm / second, respectively. A 40 nm-thick luminescent layer was provided by co-evaporation. In addition, the substrate temperature at the time of vapor deposition was room temperature.

  Further, the heating boat containing the electron transport material 1 was energized and heated, and deposited on the light emitting layer at a deposition rate of 0.1 nm / second to provide an electron transport layer having a thickness of 10 nm.

  In addition, the heating boat containing the electron transport material 2 is further energized and heated, and deposited on the electron transport layer at a deposition rate of 0.1 nm / second to further form an electron transport layer having a thickness of 20 nm. Provided. In addition, the substrate temperature at the time of vapor deposition was room temperature.

  Then, 0.5 nm of lithium fluoride and 110 nm of aluminum were vapor-deposited, the cathode was formed, and the organic EL element 1-1 was produced.

<< Production of Organic EL Elements 1-2 to 1-96 >>
In the production of the organic EL element 1-1, organic EL elements 1-2 to 1-96 were produced in the same manner except that various materials were replaced with the compounds shown in Tables 1 to 3.

<< Evaluation of organic EL elements >>
When evaluating the obtained organic EL elements 1-1 to 1-96, the non-light emitting surface of each organic EL element after production is covered with a glass case, and a glass substrate having a thickness of 300 μm is used as a sealing substrate. An epoxy photo-curing adhesive (Lux Track LC0629B manufactured by Toagosei Co., Ltd.) is applied as a sealant around the periphery, and this is placed on the cathode so as to be in close contact with the transparent support substrate and irradiated with UV light from the glass substrate side. Then, it was cured and sealed, and an illumination device as shown in FIGS. 1 and 2 was formed and evaluated.

FIG. 1 shows a schematic view of a lighting device.
The organic EL element 101 is covered with a glass cover 102 (in addition, the sealing operation with the glass cover 102 is a glove box (purity of 99.999% or more in a nitrogen atmosphere without bringing the organic EL element 101 into contact with the atmosphere). In a high-purity nitrogen gas atmosphere).
FIG. 2 shows a cross-sectional view of the lighting device.
A transparent electrode 107 as an anode, an organic EL layer 106, and a cathode 105 are laminated in this order in the lighting device. The glass cover 102 is filled with nitrogen gas 108 and a water catching agent 109 is provided.

(1) The external extraction quantum efficiency organic EL elements at room temperature (about 23 to 25 ° C.), and a constant current drive with a current giving an initial brightness ^{2000cd / m 2, 4000cd / m} 2, immediately after the lighting start drive current [mA The external extraction quantum efficiency (η) was calculated. Here, CS-1000 (manufactured by Konica Minolta Sensing) was used for measurement of light emission luminance.
The external extraction quantum yields are all expressed as relative values based on the organic EL element 1-1 (100).

(2) driving voltages room temperature the organic EL element (about 23 to 25 ° C.), and a constant current drive with a current giving an initial brightness ^{2000cd / m 2, 4000cd / m} 2, the lighting start immediately after the drive current [mA] to The drive voltage was measured by measuring. Here, CS-1000 (manufactured by Konica Minolta Sensing) was used for measurement of light emission luminance.
The driving voltages are all expressed as relative values with the organic EL element 1-1 as a reference (100).
Drive voltage = (drive voltage of each element / drive voltage of the organic EL element 1-1) × 100
A smaller value indicates a lower drive voltage for comparison.

(3) Voltage rise rate When driven at a constant current of 10 mA / cm ² , the initial voltage and the voltage after 200 hours were measured. The increase in voltage after 200 hours with respect to the initial voltage was displayed as a percentage and used as the voltage increase rate.
Voltage increase rate (%) = [(driving voltage 200 V after driving each organic EL element / V) − (initial driving voltage / V for each organic EL element)] / (initial driving voltage / V for each organic EL element) ) × 100

(4) Luminescence half-life The luminescence half-life was evaluated according to the measurement method shown below.
Each organic EL element is driven at a constant current at room temperature (about 23 to 25 ° C.) and with a current that gives an initial luminance of 2000 cd / m ² , and a time that is ½ (1000 cd / m ² ) of the initial luminance is obtained. A measure of half-life.
The light emission half life was expressed as a relative value with the organic EL element 1-1 set as a reference (100).

(5) Initial degradation Initial degradation was evaluated according to the measurement method shown below.
At the time of measuring the light emission half-life, the time required for the light emission luminance of each organic EL element to reach 90% (1800 cd / m ² ) of the initial luminance was measured, and this was used as a measure of initial deterioration.
The initial deterioration was calculated based on the following formula.
Initial degradation = (luminance 90% arrival time of organic EL element 1-1 / hr) / (luminance 90% arrival time / hour of each organic EL element) × 100
That is, the smaller the initial deterioration value is, the smaller the initial deterioration is.

(6) Dark Spot The light-emitting surface when each organic EL element was continuously lit by driving at constant current with a current giving an initial luminance of 2000 cd / m ² at room temperature was visually evaluated.
In each element after 10 hours of continuous lighting by visual evaluation by 10 randomly selected people × When the number of people who confirmed dark spots is 5 or more △ When the number of people confirmed dark spots is 14 people ○ Dark spots It was assumed that the number of people who confirmed this was 0.
The above evaluation results are shown in Tables 1 to 3.

(7) Summary As shown in Tables 1 to 3, the organic EL elements 1-5 to 1-96 of the present invention are superior in any evaluation compared to the comparative organic EL elements 1-1 to 1-4. ing.
From these results, it can be seen that it is useful to use a certain complex as the luminescent dopant in at least improving the luminous efficiency, reducing the driving voltage, and improving the luminescent lifetime.

<< Preparation of Blue Light-Emitting Organic EL Element 2-1 >>
Transparent support provided with this ITO transparent electrode after patterning on a substrate (NH45 manufactured by NH Techno Glass Co., Ltd.) formed by depositing 100 nm of ITO (indium tin oxide) on a glass substrate of 100 mm × 100 mm × 1.1 mm as an anode The substrate was ultrasonically cleaned with isopropyl alcohol, dried with dry nitrogen gas, and subjected to UV ozone cleaning for 5 minutes.

  On this transparent support substrate, a solution obtained by diluting poly (3,4-ethylenedioxythiophene) -polystyrene sulfonate (PEDOT / PSS, Bayer, Baytron P Al 4083) to 70% with pure water at 3000 rpm for 30 seconds. After the film formation by spin coating, the film was dried at 200 ° C. for 1 hour to provide a first hole transport layer having a thickness of 30 nm.

  This substrate was transferred to a nitrogen atmosphere, and a solution obtained by dissolving 50 mg of the hole transport material 2 in 10 ml of toluene was formed on the first hole transport layer by spin coating at 1000 rpm for 30 seconds. . Furthermore, after irradiating with ultraviolet light for 180 seconds to perform photopolymerization / crosslinking, vacuum drying was performed at 60 ° C. for 1 hour to obtain a second hole transport layer.

  On this second hole transport layer, 100 mg of the host compound (host material 1) and 15 mg of the dopant compound (Comparative compound 1) were dissolved in 10 ml of butyl acetate under the conditions of 600 rpm and 30 seconds. A thin film was formed by spin coating. Furthermore, it vacuum-dried at 60 degreeC for 1 hour, and was set as the light emitting layer with a film thickness of about 70 nm.

  Next, a thin film was formed on the light emitting layer by spin coating under a condition of 1000 rpm and 30 seconds using a solution in which 50 mg of the electron transport material 3 was dissolved in 10 ml of hexafluoroisopropanol (HFIP). Furthermore, it vacuum-dried at 60 degreeC for 1 hour, and was set as the electron carrying layer with a film thickness of about 30 nm.

Subsequently, this substrate is fixed to a substrate holder of a vacuum deposition apparatus, and after the vacuum chamber is depressurized to 4 × 10 ⁻⁴ Pa, 0.4 nm of potassium fluoride is deposited as a cathode buffer layer, and further, 110 nm of aluminum is deposited. Thus, a cathode was formed, and an organic EL element 2-1 was produced.

<< Production of Organic EL Elements 2-2 to 2-96 >>
In the production of the organic EL element 2-1, organic EL elements 2-2 to 2-96 were produced in the same manner except that various materials were replaced with the compounds shown in Tables 4 to 6.

<< Evaluation of organic EL elements >>
With respect to the obtained organic EL elements 2-1 to 2-96, the performance of the elements was evaluated by the same method and standard as in Example 1.
In this example, in each evaluation of (1) external extraction quantum efficiency, (2) drive voltage, (4) light emission half life, and (5) initial deterioration, the organic EL element 2-1 was used as a reference.
The evaluation results are shown in Tables 4-6.

As shown in Tables 4 to 6, compared with the comparative organic EL elements 2-1 to 2-4, the organic EL elements 2-5 to 2-96 of the present invention are superior in any evaluation.
From these results, it can be seen that even when the light emitting layer is formed by coating, it is useful to use a certain complex as the light emitting dopant in order to improve the light emission efficiency, reduce the driving voltage, and improve the light emission lifetime. .

<< Production of White Light-Emitting Organic EL Element 3-1 >>
Transparent support provided with this ITO transparent electrode after patterning on a substrate (NH45 manufactured by NH Techno Glass Co., Ltd.) formed by depositing 100 nm of ITO (indium tin oxide) on a glass substrate of 100 mm × 100 mm × 1.1 mm as an anode The substrate was ultrasonically cleaned with isopropyl alcohol, dried with dry nitrogen gas, and subjected to UV ozone cleaning for 5 minutes.

  This transparent support substrate is fixed to a substrate holder of a commercially available vacuum evaporation apparatus, while 200 mg of the hole injection material 1 is put into a molybdenum resistance heating boat, and 200 mg of the hole transport material 1 is put into another molybdenum resistance heating boat, 200 mg of the host compound (OC-6) is put into another resistance heating boat made of molybdenum, 100 mg of the dopant compound 1 (Comparative compound 1) is put into another resistance heating boat made of molybdenum, and the dopant compound 2 is put into another resistance heating boat made of molybdenum. 100 mg of (Ir-9) was put, 200 mg of the electron transport material 1 was put into another resistance heating boat made of molybdenum, and 200 mg of the electron transport material 2 was put into another resistance heating boat made of molybdenum, and attached to a vacuum deposition apparatus.

Next, the pressure in the vacuum chamber was reduced to 4 × 10 ⁻⁴ Pa, and the heating boat containing the hole injection material 1 was energized and heated, and deposited on a transparent support substrate at a deposition rate of 0.1 nm / second to a thickness of 20 nm. The hole injection layer was provided.

Further, after reducing the vacuum chamber to 4 × 10 ⁻⁴ Pa, the heating boat containing the hole transport material 1 is heated by energization, and deposited on the transparent support substrate at a deposition rate of 0.1 nm / second. A 20 nm thick hole transport layer was provided.

  Further, the heating boat containing the host compound (OC-6), the dopant compound 1 (comparative compound 1) and the dopant compound 2 (Ir-9) was energized and heated, and the deposition rate was 0.2 nm / second, 0 respectively. A 40 nm-thick luminescent layer was provided by co-evaporation on the hole transport layer at 0.020 nm / second and 0.0010 nm / second. In addition, the substrate temperature at the time of vapor deposition was room temperature.

  Further, the heating boat containing the electron transport material 1 was energized and heated, and deposited on the light emitting layer at a deposition rate of 0.1 nm / second to provide an electron transport layer having a thickness of 10 nm.

  In addition, the heating boat containing the electron transport material 2 is further energized and heated, and deposited on the electron transport layer at a deposition rate of 0.1 nm / second to further form an electron transport layer having a thickness of 20 nm. Provided. In addition, the substrate temperature at the time of vapor deposition was room temperature.

  Subsequently, 0.5 nm of lithium fluoride and 110 nm of aluminum were vapor-deposited to form a cathode, and an organic EL element 3-1 was produced.

<< Preparation of organic EL element 3-2-3-96 >>
In the production of the organic EL element 3-1, organic EL elements 3-2 to 3-96 were produced in the same manner except that various materials were replaced with the compounds shown in Tables 7 to 9.

<< Evaluation of organic EL elements >>
With respect to the obtained organic EL elements 3-1 to 3-96, the performance of the elements was evaluated by the same method and standard as in Example 1.
In this example, in each evaluation of (1) external extraction quantum efficiency, (2) drive voltage, (4) light emission half life, and (5) initial deterioration, the organic EL element 3-1 was used as a reference.
The evaluation results are shown in Tables 7-9.

As shown in Tables 7 to 9, the organic EL elements 3-5 to 3-96 of the present invention are superior in any evaluation as compared with the comparative organic EL elements 3-1 to 3-4.
From these results, even when a single light emitting layer is formed with two dopant compounds to emit white light, a certain complex is used as a light emitting dopant in order to improve the light emission efficiency, drive voltage, and light emission lifetime. It turns out that it is useful to use.

<< Preparation of white light emitting element 4-1 >>
Transparent support provided with this ITO transparent electrode after patterning on a substrate (NH45 manufactured by NH Techno Glass Co., Ltd.) formed by depositing 100 nm of ITO (indium tin oxide) on a glass substrate of 100 mm × 100 mm × 1.1 mm as an anode The substrate was ultrasonically cleaned with isopropyl alcohol, dried with dry nitrogen gas, and subjected to UV ozone cleaning for 5 minutes.

  This transparent support substrate is fixed to a substrate holder of a commercially available vacuum evaporation apparatus, while 200 mg of the hole injection material 1 is put into a molybdenum resistance heating boat, and 200 mg of the hole transport material 1 is put into another molybdenum resistance heating boat, 200 mg of the host compound (OC-1) is put in another molybdenum resistance heating boat, 100 mg of the dopant compound 1 (Comparative Compound 1) is put in another molybdenum resistance heating boat, and the dopant compound 2 is put in another molybdenum resistance heating boat. 100 mg of (Ir-9), 100 mg of dopant compound 3 (Ir-2) in another molybdenum resistance heating boat, 200 mg of the electron transport material 1 in another molybdenum resistance heating boat, and another molybdenum product 200 mg of the electron transport material 2 was put in a resistance heating boat and attached to a vacuum evaporation apparatus.

Next, the pressure in the vacuum chamber was reduced to 4 × 10 ⁻⁴ Pa, and the heating boat containing the hole injection material 1 was energized and heated, and deposited on a transparent support substrate at a deposition rate of 0.1 nm / second to a thickness of 20 nm. The hole injection layer was provided.

Further, after reducing the vacuum chamber to 4 × 10 ⁻⁴ Pa, the heating boat containing the hole transport material 1 is heated by energization, and deposited on the transparent support substrate at a deposition rate of 0.1 nm / second. A 20 nm thick hole transport layer was provided.

  Furthermore, the hole is transported at a deposition rate of 0.2 nm / second and 0.020 nm / second, respectively, by heating the heating boat containing the host compound (OC-1) and dopant compound 1 (Comparative Compound 1). A blue light-emitting layer having a thickness of 20 nm was provided by co-evaporation on the layer. In addition, the substrate temperature at the time of vapor deposition was room temperature.

  Further, the heating boat containing the host compound (OC-1), the dopant compound 2 (Ir-9) and the dopant compound 3 (Ir-2) was energized and heated, and the deposition rate was 0.2 nm / second, 0 respectively. A yellow light emitting layer having a thickness of 20 nm was provided by co-evaporation on the hole transport layer at 0.010 nm / second and 0.0010 nm / second. In addition, the substrate temperature at the time of vapor deposition was room temperature.

  Further, the heating boat containing the electron transport material 1 was energized and heated, and deposited on the light emitting layer at a deposition rate of 0.1 nm / second to provide an electron transport layer having a thickness of 10 nm.

  In addition, the heating boat containing the electron transport material 2 is further energized and heated, and deposited on the electron transport layer at a deposition rate of 0.1 nm / second to further form an electron transport layer having a thickness of 20 nm. Provided. In addition, the substrate temperature at the time of vapor deposition was room temperature.

  Subsequently, 0.5 nm of lithium fluoride and 110 nm of aluminum were vapor-deposited to form a cathode, and an organic EL element 3-1 was produced.

<< Production of organic EL elements 4-2 to 4-96 >>
In the production of the organic EL element 1-1, organic EL elements 4-2 to 4-96 were produced in the same manner except that various materials were replaced with the compounds shown in Tables 10 to 12.

<< Evaluation of organic EL elements >>
With respect to the obtained organic EL elements 4-1 to 4-96, the performance of the elements was evaluated by the same method and standard as in Example 1.
In this example, in each evaluation of (1) external extraction quantum efficiency, (2) drive voltage, (4) light emission half life, and (5) initial deterioration, the organic EL element 4-1 was used as a reference.
The evaluation results are shown in Tables 10 to 12.

As shown in Tables 10 to 12, the organic EL elements 4-5 to 4-96 of the present invention are superior in any evaluation as compared with the comparative organic EL elements 4-1 to 4-4.
From these results, even when two light emitting layers are formed with the same host compound and three types of dopant compounds to emit white light, it is necessary to improve the light emission efficiency, drive voltage, and light emission life. It can be seen that it is useful to use certain complexes as dopants.

<< Preparation of white light emitting element 5-1 >>
Transparent support provided with this ITO transparent electrode after patterning on a substrate (NH45 manufactured by NH Techno Glass Co., Ltd.) formed by depositing 100 nm of ITO (indium tin oxide) on a glass substrate of 100 mm × 100 mm × 1.1 mm as an anode The substrate was ultrasonically cleaned with isopropyl alcohol, dried with dry nitrogen gas, and subjected to UV ozone cleaning for 5 minutes.

  This transparent support substrate is fixed to a substrate holder of a commercially available vacuum evaporation apparatus, while 200 mg of the hole injection material 1 is put into a molybdenum resistance heating boat, and 200 mg of the hole transport material 1 is put into another molybdenum resistance heating boat, 200 mg of host compound 1 (OC-1) is put into another resistance heating boat made of molybdenum, 200 mg of host compound 2 (OC-6) is put into another resistance heating boat made of molybdenum, and the dopant compound is put into another resistance heating boat made of molybdenum. 100 mg of 1 (Comparative Compound 1), 100 mg of dopant compound 2 (Ir-9) in another molybdenum resistance heating boat, 100 mg of dopant compound 3 (Ir-2) in another resistance heating boat made of molybdenum, 200 mg of electron transport material 1 is put in another resistance heating boat made of molybdenum, and another molybdenum The electron transport material 2 placed 200mg resistance heating boat, mounted in a vacuum deposition apparatus.

Next, the pressure in the vacuum chamber was reduced to 4 × 10 ⁻⁴ Pa, and the heating boat containing the hole injection material 1 was energized and heated, and deposited on a transparent support substrate at a deposition rate of 0.1 nm / second to a thickness of 20 nm. The hole injection layer was provided.

Further, after reducing the vacuum chamber to 4 × 10 ⁻⁴ Pa, the heating boat containing the hole transport material 1 is heated by energization, and deposited on the transparent support substrate at a deposition rate of 0.1 nm / second. A 20 nm thick hole transport layer was provided.

  Furthermore, the hole is transported at a deposition rate of 0.2 nm / second and 0.020 nm / second, respectively, by heating the heating boat containing the host compound (OC-1) and dopant compound 1 (Comparative Compound 1). A blue light-emitting layer having a thickness of 20 nm was provided by co-evaporation on the layer. In addition, the substrate temperature at the time of vapor deposition was room temperature.

  Further, the heating boat containing the host compound (OC-6), the dopant compound 2 (Ir-9) and the dopant compound 3 (Ir-2) was energized and heated, and the deposition rate was 0.2 nm / second, 0 respectively. A yellow light emitting layer having a thickness of 20 nm was provided by co-evaporation on the hole transport layer at 0.010 nm / second and 0.0010 nm / second. In addition, the substrate temperature at the time of vapor deposition was room temperature.

  Further, the heating boat containing the electron transport material 1 was energized and heated, and deposited on the light emitting layer at a deposition rate of 0.1 nm / second to provide an electron transport layer having a thickness of 10 nm.

  In addition, the heating boat containing the electron transport material 2 is further energized and heated, and deposited on the electron transport layer at a deposition rate of 0.1 nm / second to further form an electron transport layer having a thickness of 20 nm. Provided. In addition, the substrate temperature at the time of vapor deposition was room temperature.

  Subsequently, 0.5 nm of lithium fluoride and 110 nm of aluminum were deposited to form a cathode, and an organic EL element 5-1 was produced.

<< Production of Organic EL Element 5-2 to 5-96 >>
In the production of the organic EL element 5-1, organic EL elements 5-2 to 5-96 were produced in the same manner except that various materials were replaced with the compounds shown in Tables 13 to 15.

<< Evaluation of organic EL elements >>
With respect to the obtained organic EL elements 5-1 to 5-96, the performance of the elements was evaluated by the same method and standard as in Example 1.
In this example, in each evaluation of (1) external extraction quantum efficiency, (2) drive voltage, (4) light emission half-life, and (5) initial deterioration, the organic EL element 5-1 was used as a reference.
The evaluation results are shown in Tables 13 to 15.

As shown in Table 13 to Table 15, the organic EL elements 5-5 to 5-96 of the present invention are superior in any evaluation as compared with the comparative organic EL elements 5-1 to 5-4.
From these results, even when two light emitting layers are formed with two different host compounds and three different dopant compounds to emit white light, the light emission efficiency is improved, the driving voltage is reduced, and the light emission life is improved. Then, it turns out that it is useful to use a certain complex as a luminescent dopant.

<< Preparation of White Light-Emitting Organic EL Element 6-1 >>
After patterning on a substrate (NA-45 manufactured by NH Techno Glass Co., Ltd.) formed by depositing 100 nm of ITO (indium tin oxide) on a 100 mm × 100 mm × 1.1 mm glass substrate as an anode, this ITO transparent electrode was provided. The transparent support substrate was ultrasonically cleaned with isopropyl alcohol, dried with dry nitrogen gas, and subjected to UV ozone cleaning for 5 minutes.

  On this transparent support substrate, a solution obtained by diluting poly (3,4-ethylenedioxythiophene) -polystyrene sulfonate (PEDOT / PSS, Bayer, Baytron P Al 4083) to 70% with pure water at 3000 rpm for 30 seconds. After the film formation by spin coating, the film was dried at 200 ° C. for 1 hour to provide a first hole transport layer having a thickness of 30 nm.

  This substrate was transferred to a nitrogen atmosphere, and a solution in which 50 mg of the hole transport material 3 was dissolved in 10 ml of toluene was formed on the first hole transport layer by spin coating at 1000 rpm for 30 seconds. After irradiating with ultraviolet light for 180 seconds to carry out photopolymerization / crosslinking, vacuum drying was performed at 60 ° C. for 1 hour to form a second hole transport layer.

  On this second hole transport layer, 100 mg of host compound (OC-1), 10 mg of dopant compound 1 (comparative compound 1), 1 mg of dopant compound 2 (Ir-2) and 0.5 mg of dopant compound 3 ( Using a solution of Ir-9) dissolved in 10 ml of toluene, a film was formed by spin coating under conditions of 1000 rpm and 30 seconds to form a light emitting layer. Furthermore, it vacuum-dried at 60 degreeC for 1 hour, and was set as the light emitting layer with a film thickness of about 70 nm.

  Next, a thin film was formed on the light emitting layer by spin coating under a condition of 1000 rpm and 30 seconds using a solution in which 50 mg of the electron transport material 3 was dissolved in 10 ml of hexafluoroisopropanol (HFIP). Furthermore, it vacuum-dried at 60 degreeC for 1 hour, and was set as the electron carrying layer with a film thickness of about 30 nm.

Subsequently, this substrate is fixed to a substrate holder of a vacuum deposition apparatus, and after the vacuum chamber is depressurized to 4 × 10 ⁻⁴ Pa, 0.4 nm of potassium fluoride is deposited as a cathode buffer layer, and further, 110 nm of aluminum is deposited. Then, a cathode was formed, and an organic EL element 6-1 was produced.

  In addition, the substrate temperature at the time of vapor deposition was room temperature.

<< Production of Organic EL Elements 6-2 to 6-96 >>
Organic EL elements 6-2 to 6-96 were prepared in the same manner except that various materials were replaced with the compounds shown in Tables 16 to 18 in the production of the organic EL element 6-1.

<< Evaluation of organic EL elements >>
With respect to the obtained organic EL elements 6-1 to 6-96, the performance of the elements was evaluated by the same method and standard as in Example 1.
In this example, in each evaluation of (1) external extraction quantum efficiency, (2) driving voltage, (4) light emission half life, and (5) initial deterioration, the organic EL element 6-1 was used as a reference.
The evaluation results are shown in Tables 16-18.

As shown in Tables 16 to 18, the organic EL elements 6-5 to 6-96 of the present invention are superior in any evaluation compared to the comparative organic EL elements 6-1 to 6-4.
From these results, even when a light emitting layer is formed by coating using three types of dopant compounds to emit white light, a certain complex as a light emitting dopant is required to improve the light emission efficiency, drive voltage, and light emission lifetime. It can be seen that it is useful to use

<< Preparation of White Light-Emitting Organic EL Element 7-1 >>
After patterning on a substrate (NA-45 manufactured by NH Techno Glass Co., Ltd.) formed by depositing 100 nm of ITO (indium tin oxide) on a 100 mm × 100 mm × 1.1 mm glass substrate as an anode, this ITO transparent electrode was provided. The transparent support substrate was ultrasonically cleaned with isopropyl alcohol, dried with dry nitrogen gas, and subjected to UV ozone cleaning for 5 minutes.

  On this transparent support substrate, a solution obtained by diluting poly (3,4-ethylenedioxythiophene) -polystyrene sulfonate (PEDOT / PSS, Bayer, Baytron P Al 4083) to 70% with pure water at 3000 rpm for 30 seconds. After the film formation by spin coating, the film was dried at 200 ° C. for 1 hour to provide a first hole transport layer having a thickness of 30 nm.

  This substrate was transferred to a nitrogen atmosphere, and a solution in which 50 mg of the hole transport material 3 was dissolved in 10 ml of toluene was formed on the first hole transport layer by spin coating at 1000 rpm for 30 seconds. After irradiating with ultraviolet light for 180 seconds to carry out photopolymerization / crosslinking, vacuum drying was performed at 60 ° C. for 1 hour to form a second hole transport layer.

  On this second hole transport layer, 100 mg of host compound (host material 1), 10 mg of dopant compound 1 (comparative compound 1), 1 mg of dopant compound 2 (Ir-2) and 0.5 mg of dopant compound 3 ( Using a solution of Ir-14) dissolved in 10 ml of butyl acetate, a film was formed by spin coating under conditions of 1000 rpm and 30 seconds to form a light emitting layer. Ultraviolet light was irradiated for 15 seconds to cause photopolymerization / crosslinking, and further vacuum drying at 60 ° C. for 1 hour to obtain a light emitting layer having a film thickness of about 70 nm.

  Next, a thin film was formed on the light emitting layer by spin coating under a condition of 1000 rpm and 30 seconds using a solution of 50 mg of the electron transport material 4 dissolved in 10 ml of methanol. After irradiating with ultraviolet light for 60 seconds to carry out photopolymerization / crosslinking, it was further vacuum dried at 60 ° C. for 1 hour to obtain an electron transport layer having a film thickness of about 30 nm.

Subsequently, this substrate is fixed to a substrate holder of a vacuum deposition apparatus, and after the vacuum chamber is depressurized to 4 × 10 ⁻⁴ Pa, 0.4 nm of potassium fluoride is deposited as a cathode buffer layer, and further, 110 nm of aluminum is deposited. Then, a cathode was formed, and an organic EL element 7-1 was produced.

  In addition, the substrate temperature at the time of vapor deposition was room temperature.

<< Production of Organic EL Elements 7-2 to 7-96 >>
Organic EL elements 7-2 to 7-96 were prepared in the same manner except that various materials were replaced with the compounds shown in Tables 19 to 21 in the preparation of the organic EL element 7-1.

<< Evaluation of organic EL elements >>
With respect to the obtained organic EL elements 7-1 to 7-96, the performance of the elements was evaluated by the same method and standard as in Example 1.
In this example, in each evaluation of (1) external extraction quantum efficiency, (2) driving voltage, (4) light emission half life, and (5) initial deterioration, the organic EL element 7-1 was used as a reference.
The evaluation results are shown in Table 19 to Table 21.

As shown in Table 19 to Table 21, the organic EL elements 7-5 to 7-96 of the present invention are superior in any evaluation as compared with the comparative organic EL elements 7-1 to 7-4.
From these results, even when a light emitting layer is formed by coating using three types of dopant compounds to emit white light, a certain complex as a light emitting dopant is required to improve the light emission efficiency, drive voltage, and light emission lifetime. It can be seen that it is useful to use

DESCRIPTION OF SYMBOLS 101 Organic EL element 102 Glass cover 105 Cathode 106 Organic EL layer 107 Transparent electrode 108 Nitrogen gas 109 Water catching agent

Claims (19)

In an organic electroluminescence device comprising an anode, a cathode, and an organic layer composed of one or more layers having at least a light emitting layer, wherein the organic layer is disposed between the anode and the cathode.
At least 1 layer of the said organic layer contains the hexadentate type iridium ortho metal complex represented by General formula (1), The organic electroluminescent element characterized by the above-mentioned.

[In General Formula (1), L1, L2, and L3 each have a bidentate ligand structure, and are bonded to iridium at two positions by the coordinating atoms of each. V1, V2 and V3 represent a divalent linking group, L1 and L2 are linked by a linking group V1, L2 and L3 are linked by a linking group V2, and L3 and L1 are covalently linked by a linking group V3. The hexadentate ligand (Lig) represented by this is formed. n represents 0 or 1, and when n = 0, the linking group V3 does not exist. ]

[In General Formula (2), L1, L2, and L3 each have the partial structure shown in General Formula (3). L1, L2, and L3 may be the same or different from each other. ]

[In the general formula (3), CyD1, CyD2, and CyD3 may be the same or different from each other, and represent an aromatic heterocycle that is coordinated to iridium by a nitrogen atom or a carbene carbon atom, and CyC1, CyC2 and CyC3 may be the same or different from each other, and each represents an aromatic hydrocarbon ring or an aromatic heterocycle in which a carbon atom is bonded to iridium by a covalent bond.
CyD1 and CyC1 are covalently linked by V11 to form a bidentate ligand structure, CyD2 and CyC2 are covalently linked by V12 to form a bidentate ligand structure, and CyD3 and CyC3 are covalently linked by V13 Thus, a bidentate ligand structure is obtained.
V11, V12 and V13 may be the same as or different from each other, and each represents a single bond or a linking group. ] The organic electroluminescent device according to claim 1,
In the general formula (1) or the general formula (2), CyD1, CyC1, CyD2, CyC2, CyD3, and CyC3 constituting the bidentate ligands L1, L2, and L3 are not conjugated with each aromatic ring. An organic electroluminescence device, wherein the organic electroluminescence device is bonded to a linking group V1, V2, or V3 through a substituent. The organic electroluminescent element according to claim 1 or 2,
In the general formula (1) or the general formula (2), the bidentate ligands L1, L2, and L3 are represented by the general formula (4) or the general formula (5).

[In General Formula (4) and General Formula (5), Ring A, Ring B, Ring C, Ring D and Ring E represent a 5-membered or 6-membered aromatic hydrocarbon ring or aromatic heterocycle, and X1, X2 and X3 represent a carbon atom or a nitrogen atom.
Cy represents a 5- or 6-membered aromatic hydrocarbon ring, aromatic heterocycle, non-aromatic hydrocarbon ring or non-aromatic heterocycle, and n0 represents 0 or 1.
R1, R2, R3 and R4 each independently represents a hydrogen atom, a halogen atom or a cyano group, or an optionally substituted alkyl group, cycloalkyl group, alkenyl group, alkynyl group, alkoxy group, cycloalkyloxy Group, amino group, silyl group, arylalkyl group, aryl group, heteroaryl group, aryloxy group, heteroaryloxy group, arylthio group, heteroarylthio group, non-aromatic hydrocarbon ring group or non-aromatic heterocyclic group Represents.
Ra, Rb, Rc and Rd each independently represents a hydrogen atom, a halogen atom or a cyano group, or an optionally substituted alkyl group, cycloalkyl group, alkenyl group, alkynyl group, alkoxy group, amino group, A silyl group, an arylalkyl group, an aryl group, a heteroaryl group, an aryloxy group, a heteroaryloxy group, an arylthio group, a heteroarylthio group, a non-aromatic hydrocarbon ring group or a non-aromatic heterocyclic group is represented.
na, nb, nc and nd represent an integer of 1 to 3.
A plurality of Ra, Rb, Rc and Rd may be the same as or different from each other.
Ra and ring A, Rb and ring B, Rc and ring C, Rd and ring D, and Ra and ring E may be bonded at two positions to form a condensed ring.
n1 and n2 represent 0 or 1, and n1 + n2> 1.
V10 represents a linking group or a single bond.
The linking groups V1, V2, and V3 are bonded to the bidentate ligands L1, L2, and L3 as any two selected from R1 to R4. ] The organic electroluminescent element according to claim 1 or 2,
In the general formula (1) or the general formula (2), the bidentate ligands L1, L2, and L3 are represented by the general formula (4-1) or the general formula (5-1). Electroluminescence element.

[In General Formula (4-1) and General Formula (5-1), Ring A, Ring B, Ring C, Ring D and Ring E are 5-membered or 6-membered aromatic hydrocarbon rings or aromatic heterocycles. X1, X2 and X3 represent a carbon atom or a nitrogen atom.
Cy represents a 5- or 6-membered aromatic hydrocarbon ring, aromatic heterocycle, non-aromatic hydrocarbon ring or non-aromatic heterocycle, and n0 represents 0 or 1.
R1, R2, R3 and R4 each independently represents a hydrogen atom, a halogen atom or a cyano group, or an optionally substituted alkyl group, cycloalkyl group, alkenyl group, alkynyl group, alkoxy group, cycloalkyloxy Group, amino group, silyl group, arylalkyl group, aryl group, heteroaryl group, aryloxy group, heteroaryloxy group, arylthio group, heteroarylthio group, non-aromatic hydrocarbon ring group or non-aromatic heterocyclic group Represents.
Ra, Rb, Rc and Rd each independently represents a hydrogen atom, a halogen atom or a cyano group, or an optionally substituted alkyl group, cycloalkyl group, alkenyl group, alkynyl group, alkoxy group, amino group, A silyl group, an arylalkyl group, an aryl group, a heteroaryl group, an aryloxy group, a heteroaryloxy group, an arylthio group, a heteroarylthio group, a non-aromatic hydrocarbon ring group or a non-aromatic heterocyclic group is represented.
na, nb, nc and nd represent an integer of 1 to 3.
A plurality of Ra, Rb, Rc and Rd may be the same as or different from each other.
Ra and ring A, Rb and ring B, Rc and ring C, Rd and ring D, and Ra and ring E may be bonded at two positions to form a condensed ring.
n1 and n2 represent 0 or 1, and n1 + n2> 1.
The linking groups V1, V2, and V3 are bonded to the bidentate ligands L1, L2, and L3 as any two selected from R1 to R4. ] The organic electroluminescent element according to claim 1 or 2,
In the general formula (1) or the general formula (2), the bidentate ligands L1, L2, and L3 are represented by the general formula (4-2) or the general formula (5-2). Electroluminescence element.

[In General Formula (4-2) and General Formula (5-2), Ring B, Ring C and Ring D represent a 5-membered or 6-membered aromatic hydrocarbon ring or aromatic heterocycle, and X1, X2, X3, X4 and X5 represent a carbon atom or a nitrogen atom.
Cy represents a 5- or 6-membered aromatic hydrocarbon ring, aromatic heterocycle, non-aromatic hydrocarbon ring or non-aromatic heterocycle, and n0 represents 0 or 1.
R1, R2, R3 and R4 each independently represents a hydrogen atom, a halogen atom or a cyano group, or an optionally substituted alkyl group, cycloalkyl group, alkenyl group, alkynyl group, alkoxy group, cycloalkyloxy Group, amino group, silyl group, arylalkyl group, aryl group, heteroaryl group, aryloxy group, heteroaryloxy group, arylthio group, heteroarylthio group, non-aromatic hydrocarbon ring group or non-aromatic heterocyclic group Represents.
Ra, Rb, Rc and Rd each independently represents a hydrogen atom, a halogen atom or a cyano group, or an optionally substituted alkyl group, cycloalkyl group, alkenyl group, alkynyl group, alkoxy group, amino group, A silyl group, an arylalkyl group, an aryl group, a heteroaryl group, an aryloxy group, a heteroaryloxy group, an arylthio group, a heteroarylthio group, a non-aromatic hydrocarbon ring group or a non-aromatic heterocyclic group is represented.
Re represents an optionally substituted alkyl group, cycloalkyl group, alkenyl group, alkynyl group, arylalkyl group, aryl group, heteroaryl group, non-aromatic hydrocarbon ring group or non-aromatic heterocyclic group.
na, nb, nc and nd represent an integer of 1 to 3.
A plurality of Ra, Rb, Rc and Rd may be the same as or different from each other.
Ra and a ring connected thereto, Rb and a ring B, Rc and a ring C, Rd and a ring D, Re and a ring connected to it may be bonded at two positions to form a condensed ring.
n1 and n2 represent 0 or 1, and n1 + n2> 1.
The linking groups V1, V2, and V3 are bonded to the bidentate ligands L1, L2, and L3 as any two selected from R1 to R4. ] The organic electroluminescent element according to claim 1 or 2,
In the general formula (1) or the general formula (2), the bidentate ligands L1, L2, and L3 are represented by the general formula (4-3) or the general formula (5-3). Electroluminescence element.

[In General Formula (4-3) and General Formula (5-3), Ring B, Ring C and Ring D represent a 5-membered or 6-membered aromatic hydrocarbon ring or aromatic heterocycle, and X1 represents CH or N is represented.
Cy represents a 5- or 6-membered aromatic hydrocarbon ring, aromatic heterocycle, non-aromatic hydrocarbon ring or non-aromatic heterocycle, and n0 represents 0 or 1.
R1, R2, R3 and R4 each independently represents a hydrogen atom, a halogen atom or a cyano group, or an optionally substituted alkyl group, cycloalkyl group, alkenyl group, alkynyl group, alkoxy group, cycloalkyloxy Group, amino group, silyl group, arylalkyl group, aryl group, heteroaryl group, aryloxy group, heteroaryloxy group, arylthio group, heteroarylthio group, non-aromatic hydrocarbon ring group or non-aromatic heterocyclic group Represents.
Ra, Rb, Rc and Rd each independently represents a hydrogen atom, a halogen atom or a cyano group, or an optionally substituted alkyl group, cycloalkyl group, alkenyl group, alkynyl group, alkoxy group, amino group, A silyl group, an arylalkyl group, an aryl group, a heteroaryl group, an aryloxy group, a heteroaryloxy group, an arylthio group, a heteroarylthio group, a non-aromatic hydrocarbon ring group or a non-aromatic heterocyclic group is represented.
Re represents an optionally substituted alkyl group, cycloalkyl group, alkenyl group, alkynyl group, arylalkyl group, aryl group, heteroaryl group, non-aromatic hydrocarbon ring group, or non-aromatic heterocyclic group.
na, nb, nc and nd represent an integer of 1 to 3.
A plurality of Ra, Rb, Rc and Rd may be the same as or different from each other.
Ra and a ring connected thereto, Rb and a ring B, Rc and a ring C, Rd and a ring D, Re and a ring connected to it may be bonded at two positions to form a condensed ring.
n2 represents 0 or 1.
The linking groups V1, V2, and V3 are bonded to the bidentate ligands L1, L2, and L3 as any two selected from R1 to R4. ] In the organic electroluminescent element according to any one of claims 3 to 6,
An organic electroluminescence device, wherein at least one of a combination of R1 and R2 or R3 and R4 is an alkyl group. In the organic electroluminescent element according to any one of claims 3 to 7,
An organic electroluminescence device, wherein at least one of a combination of R1 and R2 or R3 and R4 is an alkyl group having 2 or more carbon atoms. In the organic electroluminescent element according to any one of claims 3 to 8,
Both of R1 and R2 or the combination of R3 and R4 are alkyl groups, The organic electroluminescent element characterized by the above-mentioned. In the organic electroluminescent element according to any one of claims 3 to 9,
Both of R1 and R2 or the combination of R3 and R4 are both alkyl groups having 2 or more carbon atoms, and the organic electroluminescence device. In the organic electroluminescent element as described in any one of Claims 3-10,
R1 and R2 become connecting group V1, V2, V3, The organic electroluminescent element characterized by the above-mentioned. In the organic electroluminescent element as described in any one of Claims 3-10,
R3 and R4 become connecting group V1, V2, V3, The organic electroluminescent element characterized by the above-mentioned. In the organic electroluminescent element according to any one of claims 3 to 12,
Ring B is a benzene ring, The organic electroluminescent element characterized by the above-mentioned. In the organic electroluminescent element according to any one of claims 3 to 13,
Cy is a benzene ring, The organic electroluminescent element characterized by the above-mentioned. In the organic electroluminescent element according to any one of claims 1 to 14,
Derivatives having a ring structure in which at least one of the carbon atoms of the hydrocarbon ring constituting the fluorene derivative, dibenzofuran derivative, dibenzothiophene derivative, carbazole derivative or their condensed ring compound derivative is substituted with a nitrogen atom in the light emitting layer An organic electroluminescence device comprising: In the organic electroluminescent element as described in any one of Claims 1-15,
The organic layer contains at least one compound represented by the general formula (1),
An organic electroluminescence element, wherein the organic layer is formed using a wet process. In the organic electroluminescent element according to any one of claims 1 to 16,
An organic electroluminescence element characterized by emitting white light.   A display device comprising the organic electroluminescence element according to claim 1.   The illuminating device provided with the organic electroluminescent element as described in any one of Claims 1-17.

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