JP2009096861A - Organic electroluminescence element material, organic electroluminescent element, display device, and lighting system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an organic electroluminescence element material emitting light with controlled emission wavelength, showing high emission efficiency, and having a long light emission life. <P>SOLUTION: The organic electroluminescence element material is a transition metal complex having N-phenylpyrazole as a bidentate ligand, and the transition metal in the complex belongs to the 8-10 group in the element periodic table. In the N-phenylpyrazole, the 2-position of a phenyl ring is bonded to the transition metal, while another N of a pyrazole ring is coordinately bonded to the transition metal, and at least one of the 3-5 positions of the phenyl ring and the 5-position of the pyrazole ring has a substituent such as an aromatic hydrocarbon group and 5-6 membered heterocyclic group. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

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

  Conventionally, as a light-emitting electronic display device, there is an electroluminescence display (hereinafter referred to as ELD). Examples of the constituent elements of ELD include inorganic electroluminescent elements and organic electroluminescent elements (hereinafter also referred to as organic EL elements).

  Inorganic electroluminescent elements have been used as planar light sources, but an alternating high voltage is required to drive the light emitting elements. An organic EL device has a structure in which a light emitting layer containing a compound that emits light is sandwiched between a cathode and an anode, injects electrons and holes into the light emitting layer, and recombines them to generate excitons (exciton). It is an element that emits light by using light emission (fluorescence / phosphorescence) when this exciton is deactivated, and can emit light at a voltage of several volts to several tens of volts, and is also self-luminous. In addition, it is attracting attention from the viewpoints of space saving, portability and the like because it is a thin film type complete solid element with a wide viewing angle and high visibility.

  However, in organic EL elements for practical use in the future, development of organic EL elements that emit light efficiently and with high luminance with lower power consumption is desired.

  In Japanese Patent No. 3093796, a small amount of a phosphor is doped into a stilbene derivative, a distyrylarylene derivative or a tristyrylarylene derivative to achieve an improvement in light emission luminance and a longer device lifetime. Further, an element having an organic light-emitting layer in which an 8-hydroxyquinoline aluminum complex is used as a host compound and a small amount of phosphor is doped thereto (for example, JP-A 63-264692), and an 8-hydroxyquinoline aluminum complex is used as a host compound. For example, an element having an organic light emitting layer doped with a quinacridone dye (for example, JP-A-3-255190) is known.

  As described above, when light emission from excited singlet is used, the generation ratio of singlet excitons and triplet excitons is 1: 3, and thus the generation probability of luminescent excited species is 25%. Since the efficiency is about 20%, the limit of the external extraction quantum efficiency (η) is set to 5%.

  However, since Princeton University reported on an organic EL device using phosphorescence emission from an excited triplet (MA Baldo et al., Nature, 395, 151-154 (1998)), Research on materials that exhibit phosphorescence has become active.

  For example, M.M. A. Baldo et al. , Nature, 403, 17, 750-753 (2000), US Pat. No. 6,097,147, and the like.

  When the excited triplet is used, the upper limit of the internal quantum efficiency is 100%. In principle, the luminous efficiency is four times that of the excited singlet, and there is a possibility that almost the same performance as a cold cathode tube can be obtained. Therefore, it is attracting attention as a lighting application.

  For example, S.M. Lamansky et al. , J .; Am. Chem. Soc. , 123, 4304 (2001), etc., many compounds are being studied for synthesis centering on heavy metal complexes such as iridium complexes.

  In addition, the aforementioned M.I. A. Baldo et al. , Nature, 403, 17, 750-753 (2000), studies have been made using tris (2-phenylpyridine) iridium as a dopant.

In addition, M.M. E. Thompson et al. In The 10th International Works on Inorganic and Organic Electroluminescence (EL'00, Hamamatsu) used L ₂ Ir (acac) as a dopant, eg (ppy) ₂ Ir (acac), a. 0 g, Tetsuo Tsutsui, etc., again The 10th International Workshop on Inorganic and Organic Electroluminescence (EL'00, Hamamatsu), the dopant as tris (2-(p-tolyl) pyridine) iridium (Ir (ptpy) _3), tris ( Studies using benzo [h] quinoline) iridium (Ir (bzq) ₃ ) and the like are being conducted (note that these metal complexes are generally called orthometalated iridium complexes).

  The S. Lamansky et al. , J .; Am. Chem. Soc. , 123, 4304 (2001) and Japanese Patent Application Laid-Open No. 2001-247859, etc., attempts have been made to form devices using various iridium complexes.

  In order to obtain high luminous efficiency, in the 10th International Works on Inorganic and Organic Electroluminescence (EL'00, Hamamatsu), Ikai et al. Uses a hole transporting compound as a host of a phosphorescent compound.

  In addition, M.M. E. Thompson et al. Use various electron transporting materials as a host of phosphorescent compounds, doped with a novel iridium complex.

  Orthometalated complexes in which the central metal is platinum instead of iridium are also attracting attention. With respect to this type of complex, many examples are known in which ligands are characterized.

  In either case, the light emission brightness and light emission efficiency of the light emitting device are greatly improved compared to conventional devices because the emitted light is derived from phosphorescence. There was a problem that it was lower than the conventional element.

  As described above, it is difficult for phosphorescent highly efficient light-emitting materials to shorten the light emission wavelength and improve the light emission lifetime of the device, and the performance that can withstand practical use cannot be sufficiently achieved.

  In addition, regarding wavelength shortening, introduction of an electron withdrawing group such as a fluorine atom, trifluoromethyl group, cyano group or the like into phenylpyridine as a substituent, and picolinic acid or a pyrazabole-based ligand as a ligand. Although it is known to introduce, with these ligands, the emission wavelength of the luminescent material is shortened to achieve blue color, and while achieving a highly efficient device, the light emission lifetime of the device is greatly deteriorated, There was a need to improve the trade-off.

  Recently, a metal complex containing pyrazole as a ligand is known as a blue phosphorescent material (see, for example, Patent Document 1).

  However, in the device using the pyrazole-containing metal complex disclosed here for the light emitting layer, the emission wavelength is insufficient, and the lifetime of the device is not mentioned.

  As these improvements, metal complexes using multidentate pyrazole as a ligand have been disclosed (for example, see Patent Documents 2 and 3).

  Even in the device using the pyrazole-containing metal complex disclosed here for the light emitting layer, the light emitting color, the light emitting efficiency and the life as the blue phosphorescent material were not satisfactory.

  Furthermore, examples of metal complexes in which a specific substituent is introduced into 1-phenylpyrazole or a characteristic of an auxiliary ligand are disclosed (for example, see Patent Documents 4, 5 and 6).

However, these also cannot satisfy both the wavelength and lifetime of the light emitting element as a blue phosphorescent material, and further improvement is demanded.
JP 2001-247859 A JP 2006-256999 A JP 2007-19462 A International Publication No. 04/085450 Pamphlet International Publication No. 05/053912 Pamphlet US Patent Publication No. 2006-228578

  The present invention has been made in view of the above problems, and an object of the present invention is to provide an organic EL element material having a controlled emission wavelength, high emission efficiency, and a long emission lifetime, and an organic EL element using the same An illumination device and a display device are provided.

  The above object of the present invention has been achieved by the following constitution.

  1. An organic electroluminescence element material comprising a metal complex represented by the following general formula (1).

[Wherein, R ₁ , R ₂ , R ₃ and R ₄ each represents a hydrogen atom or a substituent. n1 represents the integer of 1-4. However, at least one of R ₁ and R ₂ represents a substituent represented by the following general formula (2). X ₁ -L ₁ -X ₂ represents a bidentate ligand, and X ₁ and X ₂ each independently represent a carbon atom, a nitrogen atom or an oxygen atom. L1 represents an atomic group that forms a bidentate ligand together with X ₁ and X ₂ . m1 represents an integer of 1, 2 or 3, m2 represents an integer of 0, 1 or 2, and m1 + m2 is 2 or 3. M ₁ represents a group 8-10 transition metal element in the periodic table. ]

[Wherein, Z1 represents an atomic group necessary for forming a 5-membered or 6-membered hydrocarbon ring group or a 5-membered to 6-membered heterocyclic group. A represents a carbon atom or a nitrogen atom. R ₁₁ represents a substituent. R ₁₂ represents a hydrogen atom or a substituent, and n12 represents an integer of 1 to 4. However, when a plurality of R ₁₂ are present, each R ₁₂ may be the same or different. ]
2. 2. The organic electroluminescent element material according to 1, wherein the metal complex represented by the general formula (1) is a metal complex represented by the following general formula (3).

[Wherein, R ₁ , R ₂ , R ₃ and R ₄ each represents a hydrogen atom or a substituent. n1 represents an integer of 1 to 3. Z2 represents an atomic group necessary to form a 5-membered or 6-membered hydrocarbon ring group or a 5- to 6-membered heterocyclic group, R ₅ is sterically parameter value (Es value) -0. Represents 5 or less substituents. R ₆ represents a hydrogen atom or a substituent, and n2 represents an integer of 1 to 4. X ₁ -L ₁ -X ₂ represents a bidentate ligand, and X ₁ and X ₂ each independently represent a carbon atom, a nitrogen atom or an oxygen atom. L1 represents an atomic group that forms a bidentate ligand together with X ₁ and X ₂ . m1 represents an integer of 1, 2 or 3, m2 represents an integer of 0, 1 or 2, while m1 + m2 represents 2 or 3. M ₁ represents a group 8-10 transition metal element in the periodic table. ]
3. 3. The organic electroluminescent element material according to 2, wherein the metal complex represented by the general formula (3) is a metal complex represented by the following general formula (4).

[Wherein, R ₁ , R ₂ , R ₃ and R ₄ each represents a hydrogen atom or a substituent. n1 represents an integer of 1 to 3. R ₅ represents a substituent having a steric parameter value (Es value) of −0.5 or less. R ₆ represents a hydrogen atom or a substituent, n2 is an integer of 1-4. X ₁ -L ₁ -X ₂ represents a bidentate ligand, and X ₁ and X ₂ each independently represent a carbon atom, a nitrogen atom or an oxygen atom. L1 represents an atomic group that forms a bidentate ligand together with X ₁ and X ₂ . m1 represents an integer of 1, 2 or 3, m2 represents an integer of 0, 1 or 2, and m1 + m2 is 2 or 3. M ₁ represents a group 8-10 transition metal element in the periodic table. ]
4). 4. The organic electroluminescence element material according to 3, wherein the metal complex represented by the general formula (4) is a metal complex represented by the following general formula (5).

[Wherein, R ₁ , R ₂ , R ₃ and R ₄ each represents a hydrogen atom or a substituent. n1 represents an integer of 1 to 3. R ₅ and R ₇ each represent a substituent having a steric parameter value (Es value) of −0.5 or less. R ₆ represents a hydrogen atom or a substituent, and n2 represents an integer of 1 to 3. X ₁ -L ₁ -X ₂ represents a bidentate ligand, and X ₁ and X ₂ each independently represent a carbon atom, a nitrogen atom or an oxygen atom. L1 represents an atomic group that forms a bidentate ligand together with X ₁ and X ₂ . m1 represents an integer of 1, 2 or 3, m2 represents an integer of 0, 1 or 2, and m1 + m2 is 2 or 3. M ₁ represents a group 8-10 transition metal element in the periodic table. ]
5). 2. The organic electroluminescence element material according to 1, wherein the metal complex represented by the general formula (1) is a metal complex represented by the following general formula (6).

[Wherein R ₁ , R ₃ and R ₄ each represents a hydrogen atom or a substituent. n1 represents the integer of 1-4. Z2 represents an atomic group necessary to form a 5-membered or 6-membered hydrocarbon ring group or a 5- to 6-membered heterocyclic group, R ₅ is sterically parameter value (Es value) -0. Represents 5 or less substituents. R ₆ represents a hydrogen atom or a substituent, n2 is an integer of 1-4. X ₁ -L ₁ -X ₂ represents a bidentate ligand, and X ₁ and X ₂ each independently represent a carbon atom, a nitrogen atom or an oxygen atom. L1 represents an atomic group that forms a bidentate ligand together with X ₁ and X ₂ . m1 represents an integer of 1, 2 or 3, m2 represents an integer of 0, 1 or 2, and m1 + m2 is 2 or 3. M ₁ represents a group 8-10 transition metal element in the periodic table. ]
6). 6. The organic electroluminescence element material according to 5, wherein the metal complex represented by the general formula (6) is a metal complex represented by the following general formula (7).

[Wherein R ₁ , R ₃ and R ₄ each represents a hydrogen atom or a substituent. n1 represents the integer of 1-4. R ₅ represents a substituent having a steric parameter value (Es value) of −0.5 or less. R ₆ represents a hydrogen atom or a substituent, n2 is an integer of 1-4. X ₁ -L ₁ -X ₂ represents a bidentate ligand, and X ₁ and X ₂ each independently represent a carbon atom, a nitrogen atom or an oxygen atom. L1 represents an atomic group that forms a bidentate ligand together with X ₁ and X ₂ . m1 represents an integer of 1, 2 or 3, m2 represents an integer of 0, 1 or 2, and m1 + m2 is 2 or 3. M ₁ represents a group 8-10 transition metal element in the periodic table. ]
7). 7. The organic electroluminescence element material according to 6, wherein the metal complex represented by the general formula (7) is a metal complex represented by the following general formula (8).

[Wherein R ₁ , R ₃ and R ₄ each represents a hydrogen atom or a substituent. n1 represents the integer of 1-4. R ₅ and R ₇ each represent a substituent having a steric parameter value (Es value) of −0.5 or less. R ₆ represents a hydrogen atom or a substituent, n3 denotes an integer of 1 to 3. X ₁ -L ₁ -X ₂ represents a bidentate ligand, and X ₁ and X ₂ each independently represent a carbon atom, a nitrogen atom or an oxygen atom. L1 represents an atomic group that forms a bidentate ligand together with X ₁ and X ₂ . m1 represents an integer of 1, 2 or 3, m2 represents an integer of 0, 1 or 2, and m1 + m2 is 2 or 3. M ₁ which is a central metal represents a transition metal element of Group 8 to Group 10 in the periodic table. ]
8). 8. The bidentate ligand represented by X ₁ -L ₁ -X ₂ is a compound represented by the following general formula (9), Organic electroluminescence element material.

Wherein, Z3, Z4 represents a 5- or 6-membered hydrocarbon ring group or 5-membered or 6-membered heterocyclic group, R _8, R ₉ each represent a hydrogen atom or a substituent. n4 and n5 represent an integer of 1 to 4. R ₁₀ represents a substituent. A represents -C (R1a) = (wherein R1a represents a hydrogen atom or a substituent) or a nitrogen atom. ]
9. 9. The organic electroluminescence device material as described in 8 above, wherein the bidentate ligand represented by X ₁ -L ₁ -X ₂ is a compound represented by the following general formula (10):

[Wherein R ₈ and R ₉ each represents a hydrogen atom or a substituent. n4 and n5 represent an integer of 1 to 4. R ₁₀ represents a substituent having a steric parameter value (Es value) of −0.5 or less. R ₁₂ represents a hydrogen atom or a substituent, and n6 represents an integer of 1 to 2. ]
10. 10. The organic electroluminescence device material as described in 9 above, wherein the bidentate ligand represented by X ₁ -L ₁ -X ₂ is a compound represented by the following general formula (11).

[Wherein R ₈ and R ₉ each represents a hydrogen atom or a substituent. n4 and n5 represent an integer of 1 to 4. R ₁₀ and R ₁₁ each represent a substituent having a steric parameter value (Es value) of −0.5 or less. R ₁₂ represents a hydrogen atom or a substituent, and n6 represents an integer of 1 to 2. ]
11. In the metal complex represented by at least one selected from the group consisting of the general formula (1) and the general formulas (3) to (8),
m2 is 0, The organic electroluminescent element material of any one of said 1-10 characterized by the above-mentioned.

12 In the metal complex represented by at least one selected from the group consisting of the general formula (1) and the general formulas (3) to (8),
The organic electroluminescence device material according to any one of 1 to 10, wherein m2 is 1.

  13. 11. The organic electroluminescence device material according to any one of 2 to 7, 9, and 10, wherein the substituent having a steric parameter value (Es value) of −0.5 or less is an electron donating group. .

14 14. The organic electroluminescence element material according to any one of 1 to 13, wherein M ₁ is iridium.

15. 14. The organic electroluminescent element material according to any one of 1 to 13, wherein M ₁ is platinum.

  16. 16. The organic electroluminescence element material according to any one of 1 to 15, wherein the first emission wavelength is in the range of 400 to 500 nm.

  17. 17. The organic electroluminescence device as described in any one of 1 to 16 above, which comprises a polymer having a metal complex represented by any one of the general formulas (1) to (8) as a partial structure. material.

  18. The organic electroluminescent element material containing the organic electroluminescent element material of any one of said 1-17.

  19. 19. The organic electroluminescence device as described in 18 above, wherein the organic electroluminescence device comprises a light emitting layer as a constituent layer, and the light emitting layer contains the organic electroluminescence device material described in any one of 1 to 17 above.

  20. A light-emitting layer as a constituent layer, and the light-emitting layer contains a carboline derivative or a derivative having a ring structure in which at least one of carbon atoms of a hydrocarbon ring constituting the carboline ring of the carboline derivative is substituted with a nitrogen atom 20. The organic electroluminescence device as described in 18 or 19 above.

  21. It has a hole blocking layer as a constituent layer, and the hole blocking layer has a ring structure in which at least one of carbon atoms of a carboline derivative or a hydrocarbon ring constituting a carboline ring of the carboline derivative is substituted with a nitrogen atom. 21. The organic electroluminescence device according to any one of 18 to 20, wherein the organic electroluminescence device comprises a derivative.

  22. The organic electroluminescent element of any one of said 18-21 is provided, The display apparatus characterized by the above-mentioned.

  23. It has an organic electroluminescent element of any one of said 18-21, The illuminating device characterized by the above-mentioned.

  According to the present invention, an organic EL element material having a controlled emission wavelength, high emission efficiency, and a long emission lifetime, an organic EL element using the same, an illumination device, and a display device can be provided.

  In the organic EL element material of the present invention, the molecular design of the organic EL element material useful for the organic EL element has been successfully achieved by the constitution defined in any one of claims 1 to 17.

  In addition, by using the organic EL element material, it was possible to provide an organic EL element, an illumination device, and a display device that have a light emission wavelength controlled, a high light emission efficiency, and a long light emission lifetime.

  Hereinafter, details of each component according to the present invention will be sequentially described.

  The metal complex which concerns on the organic EL element material of this invention is demonstrated.

  As a result of intensive studies on the above problems, the present inventors are a preferred embodiment of the metal complex represented by the general formula (1), and further the metal complex represented by the general formula (1). The present inventors have found that the organic EL element containing the metal complex represented by any one of the general formulas (3) to (8) as an organic EL element material greatly improves the light emission efficiency and the light emission lifetime.

  The present inventors took a pyrazole derivative as an example, and the stability of the complex is greatly influenced by the substitution position and type of the substituent on the parent pyrazole derivative, or the influence of a ligand other than pyrazole. Has been found to have a large effect on the light emission lifetime.

  A substituent having a specific steric parameter or an electronic parameter is introduced into a specific ring structure (1-phenylpyrazole) of the metal complex according to the present invention, and a heterocycle, an aromatic heterocycle or an aromatic hydrocarbon ring group is introduced. As a result, the lifetime of light emission, which has been a problem of organic EL devices manufactured using conventional blue metal complexes, especially organic EL device materials whose emission wavelength is controlled to the short wavelength side only by electron-withdrawing groups, is greatly increased. As a result, it has been found that the luminous efficiency and the luminous lifetime can be compatible.

  In addition, it was found that by specifying the substitution position, size, and electronic properties of the aromatic cyclic substituent as in the present invention, the lifetime of a blue light emitting device with excellent color purity can be further extended. Succeeded in greatly improving the light emission life of EL elements.

  The concept of the present invention will be described by taking 1,5-diphenylpyrazole as an example and further introducing an aromatic hydrocarbon ring such as a phenyl group at the 5-position of 1-phenylpyrazole.

  For example, it is known that introduction of a phenyl group at the 5-position of 1-phenylpyrazole is difficult in terms of synthesis as compared with the case where a linear alkyl group is introduced at the 5-position. In particular, when an aryl group having a substituent at the ortho position is introduced, there are few synthesis examples.

  Furthermore, the emission wavelength of the element containing the metal complex having 1,5-diphenylpyrazole is much longer than the prediction of molecular orbital calculation by GAUSSIAN and is broad.

  This suggests that the phenyl group at the 5-position can rotate freely. For example, the existence probability of the vibrational level due to the rotation is significantly increased even when compared with the 5-position pyrazole of the methyl position. I can explain.

As a result of intensive studies, the present inventors have introduced a cyclic substituent having a bulky substituent at the ortho position at the 5-position of 1-phenylpyrazole. (A) The twist of the phenyl group is greatly increased by the bulky substituent. And reducing the probability of vibration level by suppressing free rotation,
(B) greatly improving the stability of the molecule by introducing a bulky substituent at the 5-position;
It was found that the effect is obtained.

  In addition, the phenylpyrazole metal complex has been difficult to use as a light emitting material.

  The reason for this is that the phenylpyrazole metal complex has a non-luminescent excited state close to the excited state involved in light emission, and the shorter the wavelength, the more the excited state involved in the light emission becomes non-luminescent excited. It is presumed to be based on the hypothesis that the probability of not emitting light increases due to being closer to the state.

  In order to solve these problems, the present inventors searched for an optimal auxiliary ligand (also called a secondary ligand) for assisting light emission.

  As a result, by introducing any one of the ligands of the general formulas (9) to (11) into the metal complex, high emission efficiency and long life can be achieved while maintaining a desired emission wavelength. I found out that I can do it.

  Further, the size and electrons of the substituting atoms of the 1-phenylpyrazole skeleton represented by the metal complexes represented by these sub-ligands and the general formulas (1) and (3) to (8), respectively. We have found that combining the effects makes it possible to achieve both shorter wave length and longer life.

  The above effects have been found and the present invention has been completed.

  Moreover, even if it is a ligand which has a mother nucleus based on this invention, the light emission wavelength of a metal complex is made into a desired area | region by introduce | transducing as a substituent the auxiliary | assistant ligand to combine and a substituent itself long wave. Can be controlled. Therefore, the molecular design for imparting the function of controlling the emission wavelength of the metal complex in the long wave region (green to red) is based on the general formulas (1) and (3) to (8) according to the present invention. This is possible by using it as a starting point for the skeleton design.

(Ligand)
For example, when the metal complex according to the present invention is described in the above general formula (1), when m1> m2, the partial structure shown in parentheses having m1 or a partial structure represented by a tautomer thereof is mainly used. A partial structure shown in parentheses having m2 or a partial structure represented by a tautomer thereof is called a sub-ligand. The opposite is true when m1 <m2.

  In the present invention, as represented by the general formula (1), the metal complex is composed of a combination of a main ligand or a tautomer thereof and a subligand or a tautomer thereof, As will be described later, in the case of m2 = 0, that is, all of the ligands of the metal complex may be composed only of a partial structure represented by the main ligand or a tautomer thereof.

  Furthermore, as a so-called ligand used for forming a conventionally known metal complex, the trader may have a well-known ligand (also referred to as a coordination compound) as a ligand as necessary.

  From the viewpoint of preferably obtaining the effects described in the present invention, the type of the main ligand in the complex is preferably composed of 1 to 2 types, and more preferably 1 type.

  As a ligand used for a conventionally known metal complex, there are various known ligands. For example, “Photochemistry and Photophysics of Coordination Compounds” Springer-Verlag H. Published by Yersin, 1987, “Organometallic Chemistry-Fundamentals and Applications-” Liu Huabosha, Akio Yamamoto, published by 1982, etc. (for example, halogen ligands (preferably chlorine ligands), Nitrogen heterocyclic ligands (for example, bipyridyl, phenanthroline, etc.) and diketone ligands).

(Transition metal element of group 8-10 of the periodic table)
As the metal used for forming the metal complex represented by the general formula (1) or general formula (3) to (8) according to the present invention, a transition metal element of group 8 to 10 in the periodic table (simply transition) Among these, iridium and platinum are preferable transition metal elements.

  Furthermore, by using such an organic EL element material, it was possible to provide an organic EL element, an illuminating device, and a display device that have a light emission wavelength controlled, a high light emission efficiency, and a long light emission lifetime.

  Hereinafter, details of each component according to the present invention will be sequentially described.

  The metal complex which is the organic EL element material of the present invention will be described.

  As a content layer of the metal complex represented by the general formula (1) and the general formulas (3) to (8) according to the present invention, it may be contained in a hole transport layer, a light emitting layer, an electron blocking layer, or the like. A light emitting layer, an electron blocking layer, and the like are more preferable.

  Moreover, when it contains in a light emitting layer, by using as a light emission dopant in a light emitting layer, the efficiency improvement (high brightness) of the external extraction quantum efficiency of the organic EL element of this invention and the lifetime improvement of a light emission lifetime are achieved. be able to.

  Here, the metal complex represented by the general formula (1) according to the present invention, and then the metal complex represented by the general formulas (3) to (8) will be described.

<< Metal Complex Represented by General Formula (1) >>
The metal complex represented by the general formula (1) according to the present invention will be described.

In the general formula (1), each of the substituents represented by R ₁ , R ₂ , R ₃ and R ₄ is an 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, 1 -Propenyl group, 2-butenyl group, 1,3-butadienyl group, 2-pentenyl group, isopropenyl group, etc.), alkynyl group (for example, ethynyl group, propargyl group, etc.), aromatic hydrocarbon ring group (aromatic carbon) Also referred to as ring group, aryl group, etc., 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., aromatic heterocyclic 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, benzooxazolyl group, Thiazolyl, isoxazolyl, isothiazolyl, furazanyl, thienyl, quinolyl, benzofuryl, dibenzofuryl, benzothienyl, dibenzothienyl, indolyl, carbazolyl, carbolinyl, diazacarbazolyl Carborinyl group A quinoxalinyl group, a pyridazinyl group, a triazinyl group, a quinazolinyl group, a phthalazinyl group, etc.), a heterocyclic group (for example, a pyrrolidyl group, an imidazolidyl group, a morpholyl group) Group, oxazolidyl group, etc.), alkoxy group (for example, methoxy group, ethoxy group, propyloxy group, pentyloxy group, hexyloxy group, octyloxy group, dodecyloxy group, etc.), cycloalkoxy group (for example, cyclopentyloxy group, Cyclohexyloxy group etc.), aryloxy group (eg phenoxy group, naphthyloxy group etc.), alkylthio group (eg methylthio group, ethylthio group, propylthio group, pentylthio group, hexylthio group, octylthio group, dodecylthio group etc.), cycloal Ruthio group (eg, cyclopentylthio group, cyclohexylthio group, etc.), arylthio group (eg, phenylthio group, naphthylthio group, etc.), alkoxycarbonyl group (eg, methyloxycarbonyl group, ethyloxycarbonyl group, butyloxycarbonyl group, octyl) Oxycarbonyl group, dodecyloxycarbonyl group, etc.), aryloxycarbonyl group (eg, phenyloxycarbonyl group, naphthyloxycarbonyl group, etc.), sulfamoyl group (eg, aminosulfonyl group, methylaminosulfonyl group, dimethylaminosulfonyl group, butyl) Aminosulfonyl group, hexylaminosulfonyl group, cyclohexylaminosulfonyl group, octylaminosulfonyl group, dodecylaminosulfonyl group, phenylaminosulfonyl group, Phthalylaminosulfonyl group, 2-pyridylaminosulfonyl group, etc.), acyl group (for example, acetyl group, ethylcarbonyl group, propylcarbonyl group, pentylcarbonyl group, cyclohexylcarbonyl group, octylcarbonyl group, 2-ethylhexylcarbonyl group, dodecylcarbonyl) Group, phenylcarbonyl group, naphthylcarbonyl group, pyridylcarbonyl group, etc.), acyloxy group (for example, acetyloxy group, ethylcarbonyloxy group, butylcarbonyloxy group, octylcarbonyloxy group, dodecylcarbonyloxy group, phenylcarbonyloxy group, etc.) ), Amide group (for example, methylcarbonylamino group, ethylcarbonylamino group, dimethylcarbonylamino group, propylcarbonylamino group, pentylcarbonylamino group, Cyclohexylcarbonylamino group, 2-ethylhexylcarbonylamino group, octylcarbonylamino group, dodecylcarbonylamino group, phenylcarbonylamino group, naphthylcarbonylamino group, etc.), carbamoyl group (for example, aminocarbonyl group, methylaminocarbonyl group, dimethylamino) Carbonyl group, propylaminocarbonyl group, pentylaminocarbonyl group, cyclohexylaminocarbonyl group, octylaminocarbonyl group, 2-ethylhexylaminocarbonyl group, dodecylaminocarbonyl group, phenylaminocarbonyl group, naphthylaminocarbonyl group, 2-pyridylaminocarbonyl group Ureido group (for example, methylureido group, ethylureido group, pentylureido group, cyclohexylureido group, Tilureido group, dodecylureido group, phenylureido group, naphthylureido group, 2-pyridylaminoureido group, etc.), sulfinyl group (for example, methylsulfinyl group, ethylsulfinyl group, butylsulfinyl group, cyclohexylsulfinyl group, 2-ethylhexylsulfinyl group, dodecyl) Sulfinyl group, phenylsulfinyl group, naphthylsulfinyl group, 2-pyridylsulfinyl group, etc.), alkylsulfonyl group (for example, methylsulfonyl group, ethylsulfonyl group, butylsulfonyl group, cyclohexylsulfonyl group, 2-ethylhexylsulfonyl group, dodecylsulfonyl group) Etc.), arylsulfonyl group or heteroarylsulfonyl group (for example, phenylsulfonyl group, naphthylsulfonyl group, 2-pyridylsulfur group) Nyl 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.), halogen atoms (eg fluorine atom, chlorine atom, bromine atom etc.), fluorinated hydrocarbon groups (eg fluoromethyl group, trifluoromethyl group, pentafluoroethyl group, pentafluorophenyl group etc.), cyano group , Nitro group, hydroxy group, mercapto group, silyl group (for example, trimethylsilyl group, triisopropylsilyl group, triphenylsilyl group, phenyldiethylsilyl group, etc.), phosphono group and the like. These substituents may be further substituted with the above substituents.

A plurality of these substituents may be bonded to each other to form a ring, and when a plurality of R ₁ are present, each R ₁ may be the same or different and are connected to each other to form a ring. May be formed.

In the general formula (1), R ₁ is particularly preferably a hydrogen atom, an alkyl group, a cycloalkyl group, an aromatic hydrocarbon ring group (also referred to as an aromatic carbocyclic group or an aryl group), an aromatic heterocyclic group, Examples include heterocyclic groups.

In the general formula (1), the substituent represented by R ₂ has the same meaning as the substituent described in R ₁ in the general formula (1).

However, at least one of R ₁ and R ₂ represents a substituent represented by the following general formula (2).

(Substituent represented by the general formula (2))
In the general formula (2), examples of the 5-membered or 6-membered hydrocarbon ring group formed by Z1 include non-aromatic hydrocarbon ring groups and aromatic hydrocarbon ring groups, and non-aromatic hydrocarbon ring groups. Examples thereof include a cyclopentyl group and a cyclohexyl group. These groups may be unsubstituted or may have the above substituents.

Examples of the aromatic hydrocarbon ring group (also referred to as aromatic hydrocarbon group, aryl group, etc.) include, 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 and the like. These groups may be unsubstituted or may have the substituent described in R ₁ above.

  In the general formula (2), examples of the 5-membered to 6-membered heterocyclic group formed by Z1 include a non-aromatic heterocyclic group and an aromatic heterocyclic group, and examples of the non-aromatic heterocyclic group include For example, tetrahydrofuran ring, dioxolane ring, pyrrolidine ring, pyrazolidine ring, imidazolidine ring, oxazolidine ring, tetrahydrothiophene ring, sulfolane ring, thiazolidine ring, ε-caprolactone ring, ε-caprolactam ring, piperidine ring, hexahydropyridazine ring, Hexahydropyrimidine ring, piperazine ring, morpholine ring, tetrahydropyran ring, 1,3-dioxane ring, 1,4-dioxane ring, trioxane ring, tetrahydrothiopyran ring, thiomorpholine ring, thiomorpholine-1, 1-dioxide ring And groups derived from a pyranose ring and the like.

These groups may further have the substituent described in R ₁ above.

  Examples of the aromatic heterocyclic group include pyridyl group, pyrimidinyl group, furyl group, pyrrolyl group, imidazolyl 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, thiazolyl group, isoxazolyl group, isothiazolyl group, furazanyl group, thienyl group, pyridazinyl group, triazinyl group and the like.

These groups may further have the substituent described in R ₁ above.

In the general formula (1), a specific example of the bidentate ligand represented by X ₁ -L1-X ₂ is represented by any one of the following general formula (9) to general formula (11). Compounds such as phenylpyridine, phenylpyrazole, phenylimidazole, phenyltriazole, phenyltetrazole, pyrazabole, acetylacetone, and picolinic acid.

In the general formula (1), a transition metal element of group 8 to group 10 (also simply referred to as a transition metal) in the periodic table of elements is used as M ₁ , and among them, iridium and platinum are preferable transition metal elements.

<< Metal Complex Represented by General Formula (3) >>
One preferred embodiment of the metal complex represented by the general formula (1) is a metal complex represented by the general formula (3).

In the general formula _{(3), R 1, R} 2, R 3, the substituent represented by each of R ₄ are the compounds of formula (1), is represented by each of R _1, R _2, R _3, R ₄ Is synonymous with a substituent.

  In the general formula (3), the 5-membered or 6-membered hydrocarbon ring group formed by Z2 has the same meaning as the 5-membered or 6-membered hydrocarbon ring group formed by Z1 in the general formula (2). .

  In general formula (3), the 5-membered to 6-membered heterocyclic group formed by Z2 has the same meaning as the 5-membered to 6-membered heterocyclic group formed by Z1 in general formula (2).

In the general formula (3), R ₅ represents a substituent having a steric parameter value (Es value) of −0.5 or less, and among them, an electron donating group is preferable.

  Hereinafter, the three-dimensional parameter value (Es value) will be described.

(3D parameter value (Es value))
In the present invention, the Es value is a steric parameter derived from chemical reactivity. The smaller this value, the more sterically bulky substituent can be said.

  In general, in ester hydrolysis under acidic conditions, it is known that the influence of substituents on the progress of the reaction may only be considered as steric hindrance. The Es value is obtained by quantifying the steric hindrance.

The Es value of the substituent X is expressed by the following chemical reaction formula: X—CH ₂ COORX + H ₂ O → X—CH ₂ COOH + RXOH
The reaction rate constant kX for hydrolyzing an α-monosubstituted acetic acid ester derived from α-monosubstituted acetic acid in which one hydrogen atom of the methyl group of acetic acid is substituted with the substituent X represented by the formula And the following chemical reaction formula CH ₃ COORY + H ₂ O → CH ₃ COOH + RYOH
(RX is the same as RY), which is obtained from the reaction rate constant kH when the acetate corresponding to the α-monosubstituted acetate described above is hydrolyzed under acidic conditions.

Es = log (kX / kH)
The reaction rate decreases due to the steric hindrance of the substituent X, and as a result, kX <kH, so the Es value is usually negative. When the Es value is actually obtained, the above two reaction rate constants kX and kH are obtained and calculated by the above formula.

  Specific examples of Es values are given by Unger, S. et al. H. Hansch, C .; , Prog. Phys. Org. Chem. 12, 91 (1976). The specific numerical values are also described in “Structure-activity relationship of drugs” (Regional Chemistry Special Issue 122, Nankodo) and “American Chemical Society Reference Book, 'Exploring QSAR' p.81 Table 3-3”. There is. Next, a part is shown in Table 1.

  Here, it should be noted that the Es value defined in the present specification does not define that of the methyl group as 0, but assumes that the hydrogen atom is 0, and the Es value where the methyl group is 0 is 1 Minus 24.

R _{5 according} to the present invention has a steric parameter value (Es value) of −0.5 or less, and the Es value of the substituent is −0.5 or less, preferably in the range of −7.0 to −0.6. More preferably, it is -7.0 to -1.0.

  In the present invention, when a steric parameter value (Es value) is -0.5 or less, for example, a keto-enol tautomer may exist in Z, the keto moiety has an Es value as an enol isomer. It is converted. Even when other tautomerism exists, the Es value is converted by the same conversion method. Furthermore, the substituent having an Es value of −0.5 or less is preferably an electron-donating substituent in terms of electronic effect.

(Electron donating group (electron donating substituent))
In the present invention, the electron-donating substituent is a substituent having a negative Hammett σp value as described below, and such a substituent has an electron on the bonding atom side compared to a hydrogen atom. Easy to give.

  Specific examples of the substituent exhibiting an electron donating property include a hydroxy group, an alkoxy group (for example, methoxy group), an acetyloxy group, an amino group, a dimethylamino group, an acetylamino group, and an alkyl group (for example, methyl group, ethyl group). Group, propyl group, t-butyl group and the like) and aryl group (for example, phenyl group, mesityl group and the like). For the Hammett σp value, for example, the following documents can be referred to.

  The Hammett σp value according to the present invention refers to Hammett's substituent constant σp. Hammett's σp value is a substituent constant determined by Hammett et al. From the electronic effect of the substituent on the hydrolysis of ethyl benzoate. “Structure-activity relationship of drugs” (Nanedo: 1979), “Substituent” The groups described in “Constants for Correlation Analysis in Chemistry and Biology” (C. Hansch and A. Leo, John Wiley & Sons, New York, 1979) can be cited.

In General formula (3), the substituent represented by R < ₆ > is synonymous with the substituent represented by R < ₁ > in General formula (1).

In the general formula (3), bidentate ligands represented by X ₁ -L1-X ₂ are the compounds of formula (1), bidentate ligands represented by X ₁ -L1-X ₂ It is synonymous with.

In General Formula (3), a transition metal element of Group 8 to Group 10 in the periodic table of elements represented by M ₁ (also simply referred to as transition metal) is represented by General Formula (1) where M ₁ is in the periodic table of elements. It is synonymous with the transition metal element of Group 8-10.

<< Metal Complex Represented by Formula (4) >>
One of the more preferable embodiments of the metal complex represented by the general formula (3) includes a metal complex represented by the general formula (4).

In the general formula (4), each of the substituents represented by R ₁ , R ₂ , R ₃ , R ₄ , and R ₆ is represented by R ₁ , R ₂ , R ₃ , and R ₄ in the general formula (1). Is represented as the same as the substituent.

In the general formula (4), the substituents represented by R ₂ and R ₃ may be connected to each other to form a ring, and in the general formula (4), R ₃ and R ₄ The substituents represented by each may be linked to each other to form a ring.

In the general formula (4), the substituent represented by R ₅ and having a steric parameter value (Es value) of −0.5 or less is a steric parameter value represented by R ₅ in the general formula (3) ( (Es value) is synonymous with a substituent of -0.5 or less.

In the general formula (4), bidentate ligands represented by X ₁ -L1-X ₂ are the compounds of formula (1), bidentate ligands represented by X ₁ -L1-X ₂ It is synonymous with.

In General Formula (4), Group 8 to Group 10 transition metal elements in the periodic table represented by M ₁ (also simply referred to as transition metals) are those in General Formula (1), where M ₁ is 8 in the periodic table. It is synonymous with a transition metal element of group 10 to group 10.

<< Metal Complex Represented by Formula (5) >>
In the general formula (5), each of the substituents represented by R ₁ , R ₂ , R ₃ , R ₄ , and R ₆ is represented by R ₁ , R ₂ , R ₃ , and R ₄ in the general formula (1). Is represented as the same as the substituent.

In the general formula (5), the substituents represented by R ₂ and R ₃ may be connected to each other to form a ring. Furthermore, in the general formula (5), the substituents represented by R ₃ and R ₄ may be connected to each other to form a ring.

In the general formula (5), the substituent represented by R ₅ and R ₇ and each having a steric parameter value (Es value) of −0.5 or less is represented by R ₅ in the general formula (3). The stereo parameter value (Es value) is synonymous with a substituent having a value of -0.5 or less. In a more preferred embodiment, it is preferred that R ₅ and R ₇ are simultaneously an electron donating group.

In the general formula (5), bidentate ligands represented by X ₁ -L1-X ₂ are the compounds of formula (1), bidentate ligands represented by X ₁ -L1-X ₂ It is synonymous with.

In the general formula (5), the transition metal element of group 8 to 10 in the periodic table of elements represented by M ₁ (also simply referred to as transition metal) is represented by the general formula (1) where M ₁ is 8 in the periodic table. It is synonymous with a transition metal element of group 10 to group 10.

<< Metal Complex Represented by General Formula (6) >>
One preferred embodiment of the metal complex represented by the general formula (1) is a metal complex represented by the general formula (6).

In the general formula (6), the substituents represented by R ₁ , R ₃ , R ₄ and R ₆ are each represented by R ₁ , R ₂ , R ₃ and R ₄ in the general formula (1). Is synonymous with substituent. The substituents represented by R ₃ and R ₄ may be linked to each other to form a ring.

  In the general formula (6), the 5-membered or 6-membered hydrocarbon ring group formed by Z2 has the same meaning as the 5-membered or 6-membered hydrocarbon ring group formed by Z1 in the general formula (2). .

  In the general formula (6), the 5-membered to 6-membered heterocyclic group formed by Z2 has the same meaning as the 5-membered to 6-membered heterocyclic group formed by Z1 in the general formula (2).

In the general formula (6), the substituent represented by R ₅ and having a steric parameter value (Es value) of −0.5 or less is a steric parameter value represented by R ₅ in the general formula (3) ( (Es value) is synonymous with a substituent of -0.5 or less. Furthermore, R ₅ is preferably an electron donating group.

In the general formula (6), bidentate ligands represented by X ₁ -L1-X ₂ are the compounds of formula (1), bidentate ligands represented by X ₁ -L1-X ₂ It is synonymous with.

In the general formula (6), a transition metal element of group 8 to group 10 (also simply referred to as a transition metal) in the periodic table of elements represented by M ₁ is represented by the formula 8 in which M ₁ is 8 in the periodic table of elements. It is synonymous with a transition metal element of group 10 to group 10.

<< Metal Complex Represented by General Formula (7) >>
One preferred embodiment of the metal complex represented by the general formula (6) is a metal complex represented by the general formula (7).

In the general formula (7), the substituents represented by R ₁ , R ₃ , R ₄ and R ₆ are each represented by R ₁ , R ₂ , R ₃ and R ₄ in the general formula (1). Is synonymous with substituent. The substituents represented by R ₃ and R ₄ may be linked to each other to form a ring.

In the general formula (7), the substituent represented by R ₅ and having a steric parameter value (Es value) of −0.5 or less is a steric parameter value represented by R ₅ in the general formula (3) ( (Es value) is synonymous with a substituent of -0.5 or less. Furthermore, R ₅ is preferably an electron donating group.

In the general formula (7), bidentate ligands represented by X ₁ -L1-X ₂ are the compounds of formula (1), bidentate ligands represented by X ₁ -L1-X ₂ It is synonymous with.

In the general formula (7), transition metal elements of group 8-10 of the periodic table represented by M ₁ (simply referred to as transition metals) are the compounds of formula (1), M ₁ is in the periodic table 8 It is synonymous with a transition metal element of group 10 to group 10.

<< Metal Complex Represented by Formula (8) >>
One preferred embodiment of the metal complex represented by the general formula (7) is a metal complex represented by the general formula (8).

In the general formula (8), the substituents represented by R ₁ , R ₃ , R ₄ and R ₆ are each represented by R ₁ , R ₂ , R ₃ and R ₄ in the general formula (1). Is synonymous with substituent. The substituents represented by R ₃ and R ₄ may be linked to each other to form a ring.

In the general formula (8), the substituents each represented by R ₅ and R ₇ and having a steric parameter value (Es value) of −0.5 or less are represented by R ₅ in the general formula (3). The stereo parameter value (Es value) is synonymous with a substituent having a value of -0.5 or less. Furthermore, R ₅ and R ₇ are preferably each an electron donating group.

In the general formula (8), bidentate ligands represented by X ₁ -L1-X ₂ are the compounds of formula (1), bidentate ligands represented by X ₁ -L1-X ₂ It is synonymous with.

In the general formula (8), a transition metal element of group 8-10 of the periodic table represented by M ₁ (simply referred to as transition metals) are the compounds of formula (1), M ₁ is in the periodic table 8 It is synonymous with a transition metal element of group 10 to group 10.

<< Preferred embodiment of m2 >>
In the metal complex represented by any one of the general formulas (1) to (8) according to the present invention, m2 is preferably 0 or 1.

"X ₁ 2 bidentate ligand represented by -L1-X _2"
A preferred embodiment of the bidentate ligand represented by X ₁ -L1-X _{2 according} to the present invention will be described in detail.

In the metal complexes represented by the above general formulas (1) to (8) according to the present invention, the bidentate ligand represented by X ₁ -L1-X ₂ may be the above general formula (9). A compound represented by any one of to (11) is preferably used.

"X ₁ -L1-X ₂ represented by the general formula (9)"
In the general formula (9), the 5-membered or 6-membered hydrocarbon ring group formed by Z3 and Z4 has the same meaning as the 5-membered or 6-membered hydrocarbon ring group formed by Z1 in the general formula (2). It is.

  In the general formula (9), the 5-membered to 6-membered heterocyclic group formed by Z3 and Z4 has the same meaning as the 5-membered to 6-membered heterocyclic group formed by Z1 in the general formula (2). .

In the general formula (9), the substituents represented by R ₈ , R ₉ , R ₁₀ and R 1a are each represented by R ₁ , R ₂ , R ₃ and R ₄ in the general formula (1). It is synonymous with a substituent.

"X ₁ -L ₁ -X ₂ of the general formula (10)"
In the general formula (10), the substituents represented by R ₈ , R ₉ and R ₁₂ are the substituents represented by R ₁ , R ₂ , R ₃ and R ₄ in the general formula (1), respectively. It is synonymous with. Further, R ₈ and R ₉ can be connected to each other to form a ring.

In the general formula (10), the substituent represented by R ₁₀ and having a steric parameter value (Es value) of −0.5 or less is a steric parameter value represented by R ₅ in the general formula (3) ( (Es value) is synonymous with a substituent of -0.5 or less. Further, R ₁₀ is preferably an electron donating group.

"X ₁ -L ₁ -X ₂ of the general formula (11)"
In the general formula (11), the substituents represented by R ₈ , R ₉ and R ₁₂ are the substituents represented by R ₁ , R ₂ , R ₃ and R ₄ in the general formula (1), respectively. It is synonymous with. Further, R ₈ and R ₉ can be connected to each other to form a ring.

In the general formula (11), the substituents each represented by R ₁₀ and R ₁₁ and having a steric parameter value (Es value) of −0.5 or less are represented by R ₅ in the general formula (3). The stereo parameter value (Es value) is synonymous with a substituent having a value of -0.5 or less. Further, R ₁₀ and R ₁₁ are preferably each an electron donating group.

<< Emission wavelength of metal complexes represented by general formula (1) and general formulas (3) to (8) >>
Although the 1st light emission wavelength of each metal complex represented by General formula (1) and General formula (3)-(8) based on this invention does not have limitation in particular, the range of 400 nm-500 nm is preferable.

  Here, the first emission wavelength means a component having the shortest wavelength among the emission obtained by excitation at the absorption wavelength of the metal complex, and the first emission wavelength is obtained by measurement using a fluorometer. I can do it.

<< A polymer containing any one of the general formulas (1) and (3) to (8) as a partial structure >>
Moreover, in this invention, the polymer (it is also called a polymer) which has as a partial structure the metal complex represented by any one of the said General formula (1) and General formula (3)-(8) is organic of this invention. It can be used as an EL element material.

  Hereinafter, the metal complex represented by the general formula (1) and the general formulas (3) to (8) according to the present invention, and the metal represented by the general formula (1) and the general formulas (3) to (8). Although the specific example of the polymer which has a complex as a partial structure 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), European Journal of Organic Chemistry, Vol. 4, pages 695-709 (2004), and synthesis by referring to methods such as references described in these documents. it can.

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

  << Synthesis of Exemplified Compound 101 >>

Step 1: Synthesis of Complex A 40.0 g (0.15 mol) of 5-mesityl-1-phenyl-1H-pyrazole and 21.4 g (0.06 mol) of iridium chloride trihydrate were converted to 2-ethoxy. The mixture was refluxed for 18 hours in 500 ml of ethanol and 170 ml of water while performing nitrogen bubbling.

  The reaction solution was cooled, the solid precipitated with 2 L of methanol was collected by filtration, and the solid was washed and dried with methanol to obtain 41.1 g (89.8%) of Complex A.

Step 2: Synthesis of Exemplified Compound 101 5.0 g (0.00333 mol) of Complex A and 1.7 g (0.0066 mol) of 1-mesityl-2-phenyl-1H-imidazole obtained in Step 1 were combined. In the presence of 1.6 g (0.00733 mol) of silver trifluoroacetate, the reaction was carried out at an internal temperature of 150 ° C. to 170 ° C. for 5 hours in 100 ml of phenyl acetate with nitrogen bubbling.

After cooling the reaction solution, the solvent was concentrated to 50 ml under reduced pressure, and the contents were diluted with hexane, and this mixture was separated and produced by silica gel column chromatography (hexane / succinethyl) to give 1.80 g of Exemplified Compound 101. (27.7%) was obtained. The structure was identified by ¹ H-NMR and mass spectral measurements.

In addition, the emission wavelength in the solution of the exemplary compound 101 was 454 nm (the emission wavelength was measured in 2-methyltetrahydrofuran).
In the present invention, the emission wavelength of the exemplified compound was measured as follows. First, an absorption spectrum of the exemplary compound is measured, and an absorption maximum wavelength in the range of 300 nm to 350 nm is set as excitation light.

  Using the set excitation light, the emission wavelength is measured with a fluorometer F-4500 (manufactured by Hitachi, Ltd.) while performing nitrogen bubbling.

  In addition, although there is no restriction | limiting in the solvent which can be used, 2-methyltetrahydrofuran, a dichloromethane, etc. are used preferably from a soluble viewpoint of a compound.

The concentration at the time of measurement is preferably sufficiently diluted, and specifically, it is preferably measured in the range of 10 ⁻⁶ mol / l to 10 ⁻⁴ mol / l.

  Moreover, there is no restriction | limiting in particular as temperature at the time of measurement, However, Generally, it is preferable that temperature setting of the range of room temperature-77K is performed.

<< Application of organic EL element materials to organic EL elements >>
When producing the organic EL element of the present invention using the organic EL element material of the present invention, the organic EL element of the present invention is formed on the light emitting layer or the electron blocking layer in the constituent layers (details will be described later) of the organic EL element. It is preferable to use a material. Moreover, it is preferably used as the following light emitting dopant in the light emitting layer.

(Light emitting host and light emitting dopant)
The mixing ratio of the light-emitting dopant to the light-emitting host that is the host compound that is the main component in the light-emitting layer is preferably adjusted to a range of 0.1% by mass to less than 30% by mass.

  However, the light-emitting dopant may be a mixture of a plurality of types of compounds, and the partner to be mixed may be a phosphorescent dopant or a fluorescent dopant having a different structure, other metal complexes or other structures.

  Here, the dopant (phosphorescent dopant, fluorescent dopant, etc.) that may be used in combination with the metal complex used as the light emitting dopant will be described. Luminescent dopants are roughly classified into two types: fluorescent dopants that emit fluorescence and phosphorescent dopants that emit phosphorescence.

  Representative examples of the former (fluorescent dopant) include coumarin dyes, pyran dyes, cyanine dyes, croconium dyes, squalium dyes, oxobenzanthracene dyes, fluorescein dyes, rhodamine dyes, pyrylium dyes, Examples include perylene dyes, stilbene dyes, polythiophene dyes, and rare earth complex phosphors.

  A typical example of the latter (phosphorescent dopant) is preferably a complex compound containing a transition metal element of Group 8, 9, or 10 in the periodic table, and more preferably an iridium compound or an osmium compound. Of these, iridium compounds are most preferred.

  Specifically, it is a compound described in the following patent publications.

  WO 00/70655 pamphlet, JP 2002-280178, JP 2001-181616, JP 2002-280179, JP 2001-181617, JP 2002-280180, JP 2001-247859, JP 2002-299060, JP 2001-313178, JP 2002-302671, JP 2001-345183, JP 2002-324679, International Publication No. 02/15645 pamphlet, JP 2002-332291 A, JP 2002-50484 A, JP 2002-332292 A, JP 2002-83684 A, JP 2002-540572 A, JP 2002-2002 A. No. 117978, JP 20 JP-A-2-338588, JP-A-2002-170684, JP-A-2002-352960, WO01 / 93642, JP-A-2002-50483, JP-A-2002-1000047, JP-A-2002. No. -173744, JP-A No. 2002-359082, JP-A No. 2002-17584, JP-A No. 2002-363552, JP-A No. 2002-184582, JP-A No. 2003-7469, JP-T-2002-525808. Gazette, JP2003-7471, JP2002-525833, JP2003-31366, JP2002-226495, JP2002-234894, JP2002-2335076 JP 2002-241751 A JP 2001-319779, JP 2001-319780, JP 2002-62824, JP 2002-1000047, JP 2002-203679, JP 2002-343572, JP 2002-203678 gazette etc.

  Some specific examples are shown below.

(Light emitting host)
The host compound used in the present invention represents a compound having a phosphorescence quantum yield of phosphorescence emission of less than 0.01 at room temperature (25 ° C.) among compounds contained in the light emitting layer.

  The light-emitting host used in the present invention is not particularly limited in terms of structure, but is typically a carbazole derivative, a triarylamine derivative, an aromatic borane derivative, a nitrogen-containing heterocyclic compound, a thiophene derivative, a furan derivative, an oligoarylene. Examples thereof include compounds having a basic skeleton such as compounds, or carboline derivatives and derivatives having a ring structure in which at least one carbon atom of a hydrocarbon ring constituting the carboline ring of the carboline derivative is substituted with a nitrogen atom. Among these, carbazole derivatives, carboline derivatives, and derivatives having a ring structure in which at least one carbon atom of the hydrocarbon ring constituting the carboline ring of the carboline derivative is substituted with a nitrogen atom are preferably used.

  Specific examples are given below, but the present invention is not limited thereto. These compounds are also preferably used as hole blocking materials.

  In the light emitting layer according to the present invention, a plurality of known host compounds may be used in combination as a host compound. By using a plurality of types of host compounds, it is possible to adjust the movement of charges, and the organic EL element can be made highly efficient. As these known host compounds, compounds having a hole transporting ability and an electron transporting ability, preventing the emission of longer wavelengths, and having a high Tg (glass transition temperature) are preferable.

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

  As the light-emitting host, a compound that has a hole transporting ability and an electron transporting ability, prevents an increase in the wavelength of light emission, and has a high Tg (glass transition temperature) is preferable.

  As specific examples of the light-emitting host, compounds described in the following documents are suitable. For example, Japanese Patent Laid-Open Nos. 2001-257076, 2002-308855, 2001-313179, 2002-319491, 2001-357777, 2002-334786, JP2002-8860, JP2002-334787, JP2002-15871, JP2002-334788, JP2002-43056, JP2002-334789, JP JP 2002-75645 A, JP 2002-338579 A, JP 2002-105445 A, JP 2002-343568 A, JP 2002-141173 A, JP 2002-352957 A, JP 2002-2002 A. No. 203683, JP-A-2002-3632 7, JP 2002-231453, JP 2003-3165, JP 2002-234888, JP 2003-27048, JP 2002-255934, JP 2002-286061. JP, JP-A-2002-280183, JP-A-2002-299060, JP-A-2002-302516, JP-A-2002-305083, JP-A-2002-305084, JP-A-2002-308837, etc. .

  The light emitting layer may further contain a host compound having a fluorescence maximum wavelength as a host compound. In this case, the energy transfer from the other host compound and the phosphorescent compound to the fluorescent compound allows electroluminescence as an organic EL element to be emitted from the other host compound having a fluorescence maximum wavelength. A host compound having a fluorescence maximum wavelength is preferably a compound having a high fluorescence quantum yield in a solution state.

  Here, the fluorescence quantum yield is preferably 10% or more, particularly preferably 30% or more. Specific host compounds having a maximum fluorescence wavelength include coumarin dyes, pyran dyes, cyanine dyes, croconium dyes, squalium dyes, oxobenzanthracene dyes, fluorescein dyes, rhodamine dyes, and pyrylium dyes. Perylene dyes, stilbene dyes, polythiophene dyes, and the like. The fluorescence quantum yield can be measured by the method described in 362 (1992, Maruzen) of Spectroscopic II of the Fourth Edition Experimental Chemistry Course 7.

  Next, a configuration of a typical organic EL element will be described.

<< Constituent layers of organic EL elements >>
The constituent layers of the organic EL element of the present invention will be described.

  Although the preferable specific example of the layer structure of the organic EL element of this invention is shown below, this invention is not limited to these.

(I) Anode / hole transport layer / light emitting layer / hole blocking layer / electron transport layer / cathode (ii) Anode / electron blocking layer / light emitting layer / hole blocking layer / electron transport layer / cathode (iii) Anode / Hole transport layer / electron blocking layer / light emitting layer / hole blocking layer / electron transport layer / cathode (iv) Anode / hole transport layer / electron blocking layer / light emitting layer / hole blocking layer / electron transport layer / cathode ( v) Anode / hole transport layer / electron blocking layer / light emitting layer / hole blocking layer / electron transport layer / cathode buffer layer / cathode (vi) Anode / anode buffer layer / hole transport layer / electron blocking layer / light emitting layer / Hole blocking layer / electron transport layer / cathode buffer layer / cathode (vii) Anode / anode buffer layer / hole transport layer / electron blocking layer / light emitting layer / hole blocking layer / electron transport layer / cathode buffer layer / cathode 《Blocking layer (electron blocking layer, hole blocking layer)》
The blocking layer (for example, electron blocking layer, hole blocking layer) according to the present invention will be described.

  In the present invention, the organic EL device material of the present invention is preferably used for a hole blocking layer, an electron blocking layer, and the like, and particularly preferably used for a hole blocking layer.

  When the organic EL device material of the present invention is contained in the hole blocking layer and the electron blocking layer, the organic EL device material of the present invention described in any one of claims 1 to 7 is added to the hole blocking layer or It may be contained in a state of 100% by mass as a layer constituent component such as an electron blocking layer, or may be mixed with other organic compounds.

  The thickness of the blocking layer according to the present invention is preferably 3 nm to 100 nm, and more preferably 5 nm to 30 nm.

《Hole blocking layer》
The hole blocking layer has the function of an electron transport layer in a broad sense, and is made of a material that has a function of transporting electrons but has a very small ability to transport holes, and blocks holes while transporting electrons. Thus, the probability of recombination of electrons and holes can be improved.

  Examples of the hole blocking layer include, for example, JP-A Nos. 11-204258 and 11-204359, and “Organic EL elements and the forefront of industrialization thereof (issued by NTT Corporation on November 30, 1998)” Can be applied as the hole blocking layer according to the present invention. Moreover, the structure of the electron carrying layer mentioned later can be used as a hole-blocking layer concerning this invention as needed.

  The organic EL device of the present invention has a hole blocking layer as a constituent layer, and at least one of the carbon atoms of the hydrocarbon ring constituting the carboline derivative or the carboline ring of the carboline derivative is a nitrogen atom. It is preferable to contain a derivative having a substituted ring structure.

《Electron blocking layer》
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. Furthermore, the structure of the positive hole transport layer mentioned later can be used as an electron blocking layer as needed.

  Further, the organic EL device material of the present invention is preferably used for the adjacent layer adjacent to the light emitting layer, that is, the hole blocking layer and the electron blocking layer, and particularly preferably used for the electron blocking layer.

《Hole transport layer》
The hole transport layer includes a 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 is not particularly limited, and is conventionally used as a hole charge injection / transport material in a photoconductive material, or used for a hole injection layer or a hole transport layer of an organic EL device. Any one of known ones can be selected and used.

  The hole transport material has 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.

  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.

  This 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, an ink jet method, or an LB method. Although there is no restriction | limiting in particular about the film thickness of a positive hole transport layer, Usually, it is about 5 nm-5000 nm. The hole transport layer may have a single layer structure composed of one or more of the above materials.

《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 with a single layer or a plurality of layers.

  Conventionally, in the case of a single-layer electron transport layer and a plurality of layers, the following materials are used as the electron transport material (also serving as a hole blocking material) used for the electron transport layer adjacent to the cathode side with respect to the light emitting layer. Are known.

  Further, the electron transport layer only needs to have a function of transmitting electrons injected from the cathode to the light emitting layer, and any material can be selected and used from conventionally known compounds.

  Examples of materials used for this electron transport layer (hereinafter referred to as electron transport materials) include heterocyclic tetracarboxylic acid anhydrides such as nitro-substituted fluorene derivatives, diphenylquinone derivatives, thiopyran dioxide derivatives, naphthalene perylene, carbodiimides, At least one of the carbon atoms of the fluorenylidenemethane derivative, anthraquinodimethane and anthrone derivative, oxadiazole derivative, carboline derivative, or the hydrocarbon ring constituting the carboline ring of the carboline derivative is substituted with a nitrogen atom Examples thereof include derivatives having a ring structure.

  Furthermore, in the oxadiazole derivative, a thiadiazole derivative in which the oxygen atom of the oxadiazole ring is substituted with a sulfur atom, and a quinoxaline derivative having a quinoxaline ring known as an electron-withdrawing group can also be used as an electron transport material.

  It is also possible to use a polymer material in which these materials are introduced into a polymer chain or these materials are used as a polymer main chain.

  In addition, metal complexes of 8-quinolinol derivatives such as tris (8-quinolinol) aluminum (Alq), tris (5,7-dichloro-8-quinolinol) aluminum, tris (5,7-dibromo-8-quinolinol) aluminum Tris (2-methyl-8-quinolinol) aluminum, tris (5-methyl-8-quinolinol) aluminum, bis (8-quinolinol) zinc (Znq), and the like, and the central metals of these metal complexes are In, Mg, Metal complexes replaced with Cu, Ca, Sn, Ga, or Pb can also be used as the electron transport material.

  In addition, metal-free or metal phthalocyanine, or those having terminal ends substituted with an alkyl group or a sulfonic acid group can be preferably used as the electron transport 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 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, 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, it is about 5 nm-5000 nm. This electron transport layer may have a single layer structure composed of one or more of the above materials.

  Next, an injection layer used as a constituent layer 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, between the anode and the light emitting layer or the hole transport layer, and the cathode. You may exist between a light emitting layer or an electron carrying layer.

  An injection layer is a layer that is provided between an electrode and an organic layer in order to lower drive voltage and improve light emission brightness. “Organic EL elements and the forefront of their industrialization (issued by NTT Corporation on November 30, 1998) 2 of 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).

  Details of the anode buffer layer (hole injection layer) are also described in JP-A-9-45479, JP-A-9-260062, JP-A-8-288069 and the like, and a specific example is represented by copper phthalocyanine. Phthalocyanine buffer layers, oxide buffer layers represented by vanadium oxide, amorphous carbon buffer layers, polymer buffer layers using conductive polymers such as polyaniline (emeraldine) and polythiophene, and the like.

  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. Examples include a metal buffer layer represented by an alkali metal compound buffer layer represented by lithium fluoride, an alkaline earth metal compound buffer layer represented by magnesium fluoride, and an oxide buffer layer represented by aluminum oxide.

  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 100 nm, although it depends on the material.

  This injection layer can be formed by thinning the above material by a known method such as a vacuum deposition method, a spin coating method, a casting method, an ink jet method, or an LB method. Although there is no restriction | limiting in particular about the film thickness of an injection | pouring layer, Usually, it is about 5 nm-5000 nm. The injection layer may have a single layer structure composed of one or more of the above materials.

"anode"
As the anode according to the organic EL device of the present invention, an electrode having a work function (4 eV or more) metal, alloy, electrically conductive compound and a mixture thereof as an electrode material 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. 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 according to the present invention, a cathode having a work function (4 eV or less) metal (referred to as an electron injecting metal), an alloy, an electrically conductive compound, and a mixture thereof 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, Suitable are a magnesium / aluminum mixture, a magnesium / indium mixture, an aluminum / aluminum oxide (Al ₂ O ₃ ) mixture, a lithium / aluminum mixture, aluminum and the like. The cathode can be produced by forming a thin film of these electrode materials by a method such as vapor deposition or sputtering. The sheet resistance as the cathode is preferably several hundred Ω / □ or less, and the film thickness is usually selected in the range of 10 nm to 1000 nm, preferably 50 nm to 200 nm. In order to transmit 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.

<< Substrate (also referred to as substrate, substrate, support, etc.) >>
The substrate of the organic EL device of the present invention is not particularly limited as to the type of glass, plastic and the like, and is not particularly limited as long as it is transparent. Examples of the substrate preferably used include glass and quartz. And a light transmissive resin film. A particularly preferable substrate is a resin film that can give flexibility to the organic EL element.

  Examples of the resin film include polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyethersulfone (PES), polyetherimide, polyetheretherketone, polyphenylene sulfide, polyarylate, polyimide, polycarbonate (PC), and cellulose. Examples include films made of triacetate (TAC), cellulose acetate propionate (CAP), and the like.

An inorganic or organic film or a hybrid film of both may be formed on the surface of the resin film, and the water vapor permeability (25 ± 0.5 ° C.) measured by a method according to JIS K 7129-1992. , And a relative humidity (90 ± 2)% RH) of 0.01 g / (m ² · 24 h) or less is preferable.

  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 2% 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.

  Further, a hue improving filter such as a color filter may be used in combination.

  When used in lighting applications, a film (such as an antiglare film) that has been roughened to reduce unevenness in light emission can be used in combination.

  When used as a multicolor display device, it is composed of at least two types of organic EL elements having different light emission maximum wavelengths. A suitable example for producing an organic EL element will be described.

<< 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 buffer layer / cathode. Will be described.

  First, a thin film made of a desired electrode material, for example, an anode material is formed on a suitable substrate by a method such as vapor deposition or sputtering so as to have a film thickness of 1 μm or less, preferably 10 nm to 200 nm, thereby producing an anode. . Next, a thin film containing an organic compound such as a hole injection layer, a hole transport layer, a light emitting layer, a hole blocking layer, or an electron transport layer, which is an element material, is formed thereon.

  As a method for thinning a thin film containing an organic compound, there are a spin coating method, a casting method, an ink jet method, a vapor deposition method, a printing method, and the like, but a homogeneous film is easily obtained and pinholes are not easily generated. In view of the above, the vacuum deposition method or the spin coating method is particularly preferable.

Further, a different film forming method may be applied for each layer. When a vapor deposition method is employed for film formation, the vapor deposition conditions vary depending on the type of compound used, but generally a boat heating temperature of 50 ° C. to 450 ° C., a vacuum degree of 10 ⁻⁶ Pa to 10 ⁻² Pa, and a vapor deposition rate of 0 It is desirable to select appropriately within a range of 0.01 nm / second to 50 nm / second, a substrate temperature of −50 ° C. to 300 ° C., and a film thickness of 0.1 μm to 5 μm.

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

  The organic EL device is preferably manufactured from the hole injection layer to the cathode consistently by a single vacuum, but may be taken out halfway and subjected to different film forming methods. At that time, it is necessary to consider that the work is performed in a dry inert gas atmosphere.

<Display device>
The display device of the present invention will be described. The display device of the present invention has the organic EL element.

  Although the display device of the present invention may be single color or multicolor, the multicolor display device will be described here. In the case of a multicolor display device, a shadow mask is provided only at the time of forming a light emitting layer, and a film can be formed on one surface by vapor deposition, casting, spin coating, ink jet, printing, or the like.

  When patterning is performed only on the light-emitting layer, the method is not limited, but a vapor deposition method, an inkjet method, and a printing method are preferable. In the case of using a vapor deposition method, patterning using a shadow mask is preferable.

  Moreover, it is also possible to reverse the production order to produce the cathode, the electron transport layer, the hole blocking layer, the light emitting layer, the hole transport 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. Further, even when a voltage is applied with the opposite polarity, no current flows and no light emission occurs. Further, when an AC voltage is applied, light is emitted only when the anode is in the + state and the cathode is in the-state. The alternating current waveform to be applied may be arbitrary.

  The multicolor display device can be used as a display device, a display, and various light emission sources. In a display device or display, full-color display is possible by using three types of organic EL elements of blue, red, and green light emission.

  Examples of the display device and display include a television, a personal computer, a mobile device, an AV device, a character broadcast display, and an information display in an automobile. In particular, it may be used as a display device for reproducing still images and moving images, and the driving method when used as a display device for reproducing moving images may be either a simple matrix (passive matrix) method or an active matrix method.

  Light sources include home lighting, interior lighting, clock and liquid crystal backlights, billboard advertisements, traffic lights, light sources for optical storage media, light sources for electrophotographic copying machines, light sources for optical communication processors, light sources for optical sensors, etc. For example, it is not limited to this.

《Lighting device》
The lighting device of the present invention will be described. The illuminating device of this invention has the said organic EL element.

  The organic EL element of the present invention may be used as an organic EL element having a resonator structure. The purpose of use of the organic EL element having such a resonator structure is as follows. The light source of a machine, the light source of an optical communication processing machine, the light source of a photosensor, etc. are mentioned, However It is not limited to these. Moreover, you may use for the said use by making a laser oscillation.

  Further, the organic EL element of the present invention may be used as a kind of lamp for illumination or exposure light source, a projection device for projecting an image, or a display for directly viewing a still image or a moving image. It may be used as a device (display). The driving method when used as a display device for moving image reproduction may be either a simple matrix (passive matrix) method or an active matrix method. Alternatively, a full-color display device can be manufactured by using two or more organic EL elements of the present invention having different emission colors.

  Hereinafter, an example of a display device having the organic EL element of the present invention will be described with reference to the drawings.

  FIG. 1 is a schematic view showing an example of a display device composed of organic EL elements. It is a schematic diagram of a display such as a mobile phone that displays image information by light emission of an organic EL element.

  The display 1 includes a display unit A having a plurality of pixels, a control unit B that performs image scanning of the display unit A based on image information, and the like.

  The control unit B is electrically connected to the display unit A, and sends a scanning signal and an image data signal to each of a plurality of pixels based on image information from the outside, and the pixels for each scanning line respond to the image data signal by the scanning signal. The image information is sequentially emitted to scan the image and display the image information on the display unit A.

  FIG. 2 is a schematic diagram of the display unit A.

  The display unit A includes a wiring unit including a plurality of scanning lines 5 and data lines 6, a plurality of pixels 3 and the like on a substrate. The main members of the display unit A will be described below.

  In the figure, the light emitted from the pixel 3 is extracted in the direction of the white arrow (downward).

  The scanning line 5 and the plurality of data lines 6 in the wiring portion are each made of a conductive material, and the scanning lines 5 and the data lines 6 are orthogonal to each other in a grid pattern and are connected to the pixels 3 at the orthogonal positions (details are illustrated). Not)

  When a scanning signal is applied from the scanning line 5, the pixel 3 receives an image data signal from the data line 6 and emits light according to the received image data.

  Full-color display is possible by appropriately arranging pixels in the red region, the green region, and the blue region on the same substrate.

  Next, the light emission process of the pixel will be described.

  FIG. 3 is a schematic diagram of a pixel.

  The pixel includes an organic EL element 10, a switching transistor 11, a driving transistor 12, a capacitor 13, and the like. A full color display can be performed by using red, green, and blue light emitting organic EL elements as the organic EL elements 10 in a plurality of pixels, and juxtaposing them on the same substrate.

  In FIG. 3, an image data signal is applied from the control unit B to the drain of the switching transistor 11 through the data line 6. When a scanning signal is applied from the control unit B to the gate of the switching transistor 11 via the scanning line 5, the driving of the switching transistor 11 is turned on, and the image data signal applied to the drain is supplied to the capacitor 13 and the driving transistor 12. Is transmitted to the gate.

  By transmitting the image data signal, the capacitor 13 is charged according to the potential of the image data signal, and the drive of the drive transistor 12 is turned on. The drive transistor 12 has a drain connected to the power supply line 7 and a source connected to the electrode of the organic EL element 10, and the power supply line 7 connects to the organic EL element 10 according to the potential of the image data signal applied to the gate. Current is supplied.

  When the scanning signal is moved to the next scanning line 5 by the sequential scanning of the control unit B, the driving of the switching transistor 11 is turned off. However, even if the driving of the switching transistor 11 is turned off, the capacitor 13 maintains the potential of the charged image data signal, so that the driving of the driving transistor 12 is kept on and the next scanning signal is applied. Until then, the light emission of the organic EL element 10 continues. When the scanning signal is next applied by sequential scanning, the driving transistor 12 is driven according to the potential of the next image data signal synchronized with the scanning signal, and the organic EL element 10 emits light.

  That is, the light emission of the organic EL element 10 is performed by providing the switching transistor 11 and the drive transistor 12 which are active elements with respect to the organic EL element 10 of each of the plurality of pixels, and light emission of the organic EL element 10 of each of the plurality of pixels 3. It is carried out. Such a light emitting method is called an active matrix method.

  Here, the light emission of the organic EL element 10 may be light emission of a plurality of gradations by a multi-value image data signal having a plurality of gradation potentials, or by turning on / off a predetermined light emission amount by a binary image data signal. Good. The potential of the capacitor 13 may be maintained until the next scanning signal is applied, or may be discharged immediately before the next scanning signal is applied.

  In the present invention, not only the active matrix method described above, but also a passive matrix light emission drive in which the organic EL element emits light according to the data signal only when the scanning signal is scanned.

  FIG. 4 is a schematic diagram of a passive matrix display device. In FIG. 4, a plurality of scanning lines 5 and a plurality of image data lines 6 are provided in a lattice shape so as to face each other with the pixel 3 interposed therebetween.

  When the scanning signal of the scanning line 5 is applied by sequential scanning, the pixel 3 connected to the applied scanning line 5 emits light according to the image data signal.

  In the passive matrix system, the pixel 3 has no active element, and the manufacturing cost can be reduced.

  The organic EL material of the present invention can be applied as an illumination device to an organic EL element that emits substantially white light. A plurality of light emitting colors are simultaneously emitted by a plurality of light emitting materials to obtain white light emission by color mixing. The combination of a plurality of emission colors may include three emission maximum wavelengths of the three primary colors of blue, green, and blue, or two using the relationship of complementary colors such as blue and yellow, blue green and orange, etc. The thing containing the light emission maximum wavelength may be used.

  In addition, a combination of light emitting materials for obtaining a plurality of emission colors is a combination of a plurality of phosphorescent or fluorescent materials, a light emitting material that emits fluorescence or phosphorescence, and light from the light emitting material as excitation light. Any of those combined with a dye material that emits light may be used, but in the white organic EL device according to the present invention, only a combination of a plurality of light-emitting dopants may be mixed. It is only necessary to provide a mask only when forming a light emitting layer, a hole transport layer, an electron transport layer, etc., and simply arrange them separately by coating with the mask. Since other layers are common, patterning of the mask or the like is not necessary. In addition, for example, an electrode film can be formed by a vapor deposition method, a cast method, a spin coating method, an ink jet method, a printing method, or the like, and productivity is also improved. According to this method, unlike a white organic EL device in which light emitting elements of a plurality of colors are arranged in parallel in an array, the elements themselves are luminescent white.

  There is no restriction | limiting in particular as a luminescent material used for a light emitting layer, For example, if it is a backlight in a liquid crystal display element, the metal complex which concerns on this invention so that it may suit the wavelength range corresponding to CF (color filter) characteristic, Any one of known luminescent materials may be selected and combined to whiten.

  As described above, the white light emitting organic EL element according to the present invention is used as a kind of lamp such as household illumination, interior lighting, and exposure light source as various light emitting light sources and lighting devices in addition to the display device and display. It is also useful for display devices such as backlights for liquid crystal display devices.

  Others such as backlights for watches, signboard advertisements, traffic lights, light sources for optical storage media, light sources for electrophotographic copying machines, light sources for optical communication processors, light sources for optical sensors, etc. There are a wide range of uses such as household appliances.

  EXAMPLES Hereinafter, although an Example demonstrates this invention, this invention is not limited to these. In addition, the structure of the compound used for an Example is shown below.

Example 1
<< Production of Organic EL Element 1-1 >>
After patterning on a substrate (made by NH Techno Glass Co., Ltd .: NA-45) having a 150 nm ITO film formed on glass as an anode, the transparent support substrate provided with this ITO transparent electrode was ultrasonically cleaned with iso-propyl alcohol. Then, it was dried with dry nitrogen gas, and UV ozone cleaning was performed for 5 minutes.

This transparent support substrate is fixed to a substrate holder of a commercially available vacuum deposition apparatus, while α-NPD, H4, Ir-12, BCP, and Alq ₃ are placed in five tantalum resistance heating boats, respectively. (Vacuum chamber).

  Further, lithium fluoride was placed in a resistance heating boat made of tantalum, and aluminum was placed in a resistance heating boat made of tungsten, and attached to the second vacuum tank of the vacuum evaporation apparatus.

First, after reducing the pressure in the first vacuum tank to 4 × 10 ⁻⁴ Pa, the heating boat containing α-NPD is energized and heated, and transparent at a deposition rate of 0.1 nm / second to 0.2 nm / second. It vapor-deposited so that it might become a film thickness of 20 nm on the support substrate, and provided the positive hole injection / transport layer.

  Further, the heating boat containing H4 and the boat containing Ir-12 are energized independently to adjust the deposition rate of H4 as a light emitting host and Ir-12 as a light emitting dopant to 100: 6. And it vapor-deposited so that it might become a film thickness of 30 nm, and provided the light emitting layer.

  Next, the heating boat containing BCP was energized and heated to provide a 10 nm thick hole blocking layer at a deposition rate of 0.1 nm / sec to 0.2 nm / sec.

Further, the heating boat containing Alq ₃ was energized and heated to provide an electron transport layer having a film thickness of 20 nm at a deposition rate of 0.1 nm / second to 0.2 nm / second.

  Next, after the element deposited up to the electron transport layer was transferred to the second vacuum chamber while being vacuumed, it was remotely controlled from the outside of the apparatus so that a stainless steel rectangular perforated mask was placed on the electron transport layer. Installed.

After reducing the pressure in the second vacuum chamber to 2 × 10 ⁻⁴ Pa, a cathode buffer layer having a film thickness of 0.5 nm was formed at a deposition rate of 0.01 nm / second to 0.02 nm / second by energizing a boat containing lithium fluoride. Then, a boat containing aluminum was energized, a cathode having a film thickness of 150 nm was attached at a deposition rate of 1 nm / second to 2 nm / second, and an organic EL device 1-1 was produced.

<< Production of Organic EL Elements 1-2 to 1-37 >>
In the production of the organic EL element 1-1, organic EL elements 1-2 to 1-37 were produced in the same manner except that the light emitting host, the light emitting dopant and the hole blocking material were changed as shown in Table 2.

<< Evaluation of organic EL elements >>
When evaluating the obtained organic EL elements 1-1 to 1-37, the non-light-emitting surface of each organic EL element after production was covered with a glass case, and a glass substrate having a thickness of 300 μm was used as a sealing substrate. An epoxy-based photo-curing adhesive (Lux Track LC0629B manufactured by Toagosei Co., Ltd.) is applied as a sealing material in the periphery, and this is placed on the cathode 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. 5 and 6 was formed and evaluated.

  FIG. 5 shows a schematic diagram of the lighting device, and the organic EL element 101 is covered with a glass cover 102 (in addition, the sealing operation with the glass cover is performed in a nitrogen atmosphere without bringing the organic EL element 101 into contact with the atmosphere. (In a high purity nitrogen gas atmosphere with a purity of 99.999% or more). 6 shows a cross-sectional view of the lighting device. In FIG. 6, reference numeral 105 denotes a cathode, 106 denotes an organic EL layer, and 107 denotes a glass substrate with a transparent electrode. The glass cover 102 is filled with nitrogen gas 108 and a water catching agent 109 is provided.

(External quantum efficiency)
By lighting the organic EL element at room temperature (about 23 ° C. to 25 ° C.) under a constant current condition of ^2.5 mA / cm ² and measuring the light emission luminance (L) [cd / m ² ] immediately after the start of lighting. 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 efficiency was expressed as a relative value with the organic EL element 1-1 as 100.

(Luminescent life)
The organic EL element was continuously lit at a constant current of ^2.5 mA / cm ² at room temperature, and the time (τ ^1/2 ) required to achieve half the initial luminance was measured. The light emission lifetime was expressed as a relative value at which the organic EL element 1-1 was set to 100.

(Luminescent color)
The organic EL element was visually evaluated for the color of light emitted when the organic EL element was continuously lit at a constant current of ^2.5 mA / cm ² at room temperature.

  The obtained results are shown in Table 2.

  From Table 2, it is clear that the organic EL device produced using the metal complex according to the present invention can achieve higher luminous efficiency and longer lifetime than the organic EL device of the comparative example.

  In addition, it can be seen that the blue purity is higher than that of the organic EL element of the comparative example and is useful as a blue light emitting element. Furthermore, by using a carboline derivative or a derivative having a ring structure in which at least one carbon atom of the hydrocarbon ring constituting the carboline ring of the carboline derivative is further substituted with a nitrogen atom in the light emitting layer or the hole blocking layer. Furthermore, the effect of the present invention was improved.

  Further, when the elements 1-1 and 1-37 are manufactured, when the element 1-1 is once exposed to the atmosphere for 24 hours before sealing, and sealed again under deaeration and nitrogen conditions, the element 1-1 is externally taken out. While the efficiency and the light emission lifetime were 50% or less as compared with the results shown in Table 1, the element 1-37 showed no significant change.

  Therefore, it turned out that the organic EL element produced using the metal complex which concerns on this invention has very high oxidation deterioration tolerance compared with the organic EL element of a comparative example.

Example 2
<< Preparation of Organic EL Element 2-1 >>
An anode of indium tin oxide (ITO, indium / tin = 95/5 molar ratio) was formed on a glass support substrate of 25 mm × 25 mm × 0.5 mm by a sputtering method using a DC power source (thickness 200 nm). The surface resistance of this anode was 10Ω / □.

  Polyvinylcarbazole (hole transporting binder polymer) / Ir-13 (blue light-emitting orthometalated complex) / 2- (4-biphenylyl) -5- (4-t-butylphenyl) -1,3,4 -Oxadiazole (electron transport material) = A dichloroethane solution in which a mass ratio of 200/2/50 was dissolved was applied by a spin coater to obtain a light-emitting layer having a thickness of 100 nm.

  A patterned mask (a mask with a light emission area of 5 mm × 5 mm) is placed on the organic compound layer, and lithium fluoride 0.5 nm is deposited as a cathode buffer layer and aluminum 150 nm is deposited as a cathode in a deposition apparatus to form a cathode. A blue light-emitting organic EL device 2-1 was prepared.

<< Production of Organic EL Elements 2-2 to 2-11 >>
In the production of the organic EL element 2-1, organic EL elements 2-2 to 2-11 were produced in the same manner except that the luminescent dopant was changed as shown in Table 3.

<< Evaluation of organic EL elements >>
When evaluating the obtained organic EL elements 2-1 to 2-11, the non-light-emitting surface of each organic EL element after production was covered with a glass case, and a glass substrate having a thickness of 300 μm was used as a sealing substrate. An epoxy-based photo-curing adhesive (Lux Track LC0629B manufactured by Toagosei Co., Ltd.) is applied as a sealing material in the periphery, and this is placed on the cathode 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. 5 and 6 was formed and evaluated.

  Subsequently, the luminance and luminous efficiency were measured as follows.

(Luminance, luminous efficiency)
Using Toyo Technica source measure unit type 2400, a direct current voltage is applied to the organic EL element to emit light, and a light emission luminance (cd / m ² ) and ^2.5 mA / cm ² when a direct current voltage of 10 V is applied. Luminous efficiency (lm / W) when passing current was measured. Luminance and luminous efficiency were expressed as relative values with the organic EL element 2-1 as 100.

  The obtained results are shown in Table 3.

  From Table 3, it is clear that the organic EL device produced using the metal complex according to the present invention can achieve high luminous efficiency and high luminance as compared with the organic EL device of the comparative example.

Example 3
<Production of full-color display device>
(Production of blue light emitting element)
The organic EL element 1-34 of Example 1 was used as a blue light emitting element.

(Production of green light emitting element)
A green light emitting device was produced in the same manner as in the organic EL device 1-2 of Example 1 except that Ir-13 was changed to Ir-1, and this was used as a green light emitting device.

(Production of red light emitting element)
A red light emitting device was produced in the same manner as in the organic EL device 1-2 of Example 1 except that Ir-13 was changed to Ir-9, and this was used as a red light emitting device.

  The red, green, and blue light-emitting organic EL elements produced above were juxtaposed on the same substrate to produce an active matrix type full-color display device having a configuration as shown in FIG. In FIG. 2, only the schematic diagram of the display part A of the produced display device is shown.

  That is, a plurality of pixels 3 (light emission color is a red region pixel, a green region pixel, a blue region pixel, etc.) juxtaposed with a wiring portion including a plurality of scanning lines 5 and data lines 6 on the same substrate. The scanning lines 5 and the plurality of data lines 6 in the wiring portion are each made of a conductive material, and the scanning lines 5 and the data lines 6 are orthogonal to each other in a lattice shape and are connected to the pixels 3 at the orthogonal positions (for details, see FIG. Not shown).

  The plurality of pixels 3 are driven by an active matrix system provided with an organic EL element corresponding to each emission color, a switching transistor as an active element, and a driving transistor, and a scanning signal is applied from a scanning line 5. The image data signal is received from the data line 6 and light is emitted according to the received image data. In this way, a full color display device was produced by appropriately juxtaposing red, green, and blue pixels.

  It has been found that when this full-color display device is driven, a high-brightness, high durability, and clear full-color moving image display can be obtained.

Example 4
<< Preparation of white light emitting element and white lighting device >>
The electrode of the transparent electrode substrate of Example 1 is patterned to 20 mm × 20 mm, and α-NPD is formed as a hole injection / transport layer with a thickness of 25 nm thereon, as in Example 1, and further contains H4. The heating boat, the boat containing Exemplified Compound 101 and the boat containing Ir-9 were energized independently, and the vapor deposition rate of Exemplified Compound 101 and Ir-9 as the luminescent host and CBP as the luminescent host was 100. : Adjusted to 5: 0.6, vapor-deposited to a thickness of 30 nm to provide a light emitting layer.

Next, BCP was deposited to a thickness of 10 nm to provide a hole blocking layer. Further, Alq ₃ was formed at 40 nm to provide an electron transport layer.

  Next, as in Example 1, a square perforated mask having the same shape as the transparent electrode made of stainless steel was placed on the electron injection layer, and lithium fluoride 0.5 nm was used as the cathode buffer layer and aluminum 150 nm was used as the cathode. Evaporated film was formed.

  This element was provided with a sealing can having the same method and the same structure as in Example 1, and a flat lamp as shown in FIGS. 5 and 6 was produced. When this flat lamp was energized, almost white light was obtained, and it was found that it could be used as a lighting device.

Example 5
<< Preparation of Organic EL Element 5-1 >>: On a substrate (NA-45 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 the present invention After patterning, the transparent support substrate provided with the ITO transparent electrode was ultrasonically cleaned with isopropyl alcohol, dried with dry nitrogen gas, and subjected to UV ozone cleaning for 5 minutes.

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

  On this hole injection / transport layer, a solution of 30 mg of Exemplified Compound 131 in 3 ml of toluene was formed into a film by spin coating under conditions of 1000 rpm and 30 seconds, and vacuum-dried at 60 ° C. for 1 hour. A light emitting layer having a thickness of 80 nm was obtained.

This was attached to a vacuum deposition apparatus, and then the vacuum chamber was depressurized to 4 × 10 ⁻⁴ Pa, calcium 10 nm as a cathode buffer layer and aluminum 110 nm as a cathode were deposited to form a cathode, and the organic EL element 5-1 was formed. Produced.

<< Preparation of Organic EL Elements 5-2 to 5-17 >>: Present Invention In the preparation of the organic EL element 5-1, the exemplified compound 131 used for preparing the light-emitting layer was replaced with 132, 133, 137, 138, 140, 141. , 143, 145, 147, 149, 160, 152, 154, 155, 159 and 160, respectively, except that the organic EL elements 5-2 to 5-17 were respectively produced in exactly the same manner.

<< Preparation of Organic EL Element 5-18 >>: Comparative Example Organic EL element 5-1 was prepared in the same manner as in the preparation of organic EL element 5-1, except that 3 ml of the solution of Exemplary Compound 1 was replaced with the solution described in [A] below. EL element 5-18 was produced.

[A]: A solution in which 30 mg of polyvinylcarbazole and 1.5 mg of Ir-13 (blue light-emitting orthometalated complex) are dissolved in 3 ml of toluene << Evaluation of Organic EL Elements 5-1 to 5-18 >>
When evaluating the obtained organic EL elements 5-1 to 5-18, the non-light-emitting surface of each organic EL element after fabrication was covered with a glass case, and a glass substrate having a thickness of 300 μm was used as a sealing substrate. An epoxy-based photo-curing adhesive (Lux Track LC0629B manufactured by Toagosei Co., Ltd.) is applied as a sealing material in the periphery, and this is placed on the cathode 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. 5 and 6 was formed and evaluated.

  Next, external extraction quantum efficiency and emission lifetime were measured as follows.

<< External quantum efficiency >>
The organic EL device was measured for external extraction quantum efficiency (%) when a constant current of ^2.5 mA / cm ² was applied at 23 ° C. in a dry nitrogen gas atmosphere. For the measurement, a spectral radiance meter CS-1000 (manufactured by Konica Minolta Sensing Co., Ltd.) was used.

<Luminescent life>
When driving at a constant current of ^2.5 mA / cm ^{2 in} a dry nitrogen gas atmosphere at 23 ° C., the time required for the luminance to drop to half of the luminance immediately after the start of light emission (initial luminance) was measured. Was used as an index of life as half-life time (τ ^1/2 ).

  In addition, the spectral radiance meter CS-1000 (Konica Minolta Sensing Co., Ltd. product) was similarly used for the measurement.

  The measurement results of the external extraction quantum efficiency and the light emission lifetime of the organic EL elements 5-1 to 5-18 were subjected to relative evaluation with the organic EL element 5-18 as 100.

  The results obtained are shown in Table 4 below.

  From Table 4, it was found that by using the polymer compound of the present invention for the light emitting layer, the external extraction quantum efficiency was significantly improved and the power consumption was suppressed. It was also found that the light emission life was improved.

  In addition, green light emission is obtained from the element (5-16) using the compound 159 which is the organic EL element material of the present invention, and the element (5--5) using the compound 160 which is the organic EL element material of the present invention. From 17), red light emission was obtained. All other organic EL elements emitted blue or blue-green light.

It is the schematic diagram which showed an example of the display apparatus comprised from an organic EL element. 4 is a schematic diagram of a display unit A. FIG. It is a schematic diagram of a pixel. It is a schematic diagram of a passive matrix type full-color display device. It is the schematic of an illuminating device. It is a schematic diagram of an illuminating device.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Display 3 Pixel 5 Scan line 6 Data line 7 Power supply line 10 Organic EL element 11 Switching transistor 12 Drive transistor 13 Capacitor A Display part B Control part 102 Glass cover 105 Cathode 106 Organic EL layer 107 Glass substrate with a transparent electrode 108 Nitrogen gas 109 Water catcher

Claims (23)

An organic electroluminescence element material comprising a metal complex represented by the following general formula (1).

[Wherein, R ₁ , R ₂ , R ₃ and R ₄ each represents a hydrogen atom or a substituent. n1 represents the integer of 1-4. However, at least one of R ₁ and R ₂ represents a substituent represented by the following general formula (2). X ₁ -L ₁ -X ₂ represents a bidentate ligand, and X ₁ and X ₂ each independently represent a carbon atom, a nitrogen atom or an oxygen atom. L1 represents an atomic group that forms a bidentate ligand together with X ₁ and X ₂ . m1 represents an integer of 1, 2 or 3, m2 represents an integer of 0, 1 or 2, and m1 + m2 is 2 or 3. M ₁ represents a group 8-10 transition metal element in the periodic table. ]

[Wherein, Z1 represents an atomic group necessary for forming a 5-membered or 6-membered hydrocarbon ring group or a 5-membered to 6-membered heterocyclic group. A represents a carbon atom or a nitrogen atom. R ₁₁ represents a substituent. R ₁₂ represents a hydrogen atom or a substituent, and n12 represents an integer of 1 to 4. However, when a plurality of R ₁₂ are present, each R ₁₂ may be the same or different. ] The organic electroluminescent element material according to claim 1, wherein the metal complex represented by the general formula (1) is a metal complex represented by the following general formula (3).

[Wherein, R ₁ , R ₂ , R ₃ and R ₄ each represents a hydrogen atom or a substituent. n1 represents an integer of 1 to 3. Z2 represents an atomic group necessary to form a 5-membered or 6-membered hydrocarbon ring group or a 5- to 6-membered heterocyclic group, R ₅ is sterically parameter value (Es value) -0. Represents 5 or less substituents. R ₆ represents a hydrogen atom or a substituent, and n2 represents an integer of 1 to 4. X ₁ -L ₁ -X ₂ represents a bidentate ligand, and X ₁ and X ₂ each independently represent a carbon atom, a nitrogen atom or an oxygen atom. L1 represents an atomic group that forms a bidentate ligand together with X ₁ and X ₂ . m1 represents an integer of 1, 2 or 3, m2 represents an integer of 0, 1 or 2, while m1 + m2 represents 2 or 3. M ₁ represents a group 8-10 transition metal element in the periodic table. ] The organic electroluminescent element material according to claim 2, wherein the metal complex represented by the general formula (3) is a metal complex represented by the following general formula (4).

[Wherein, R ₁ , R ₂ , R ₃ and R ₄ each represents a hydrogen atom or a substituent. n1 represents an integer of 1 to 3. R ₅ represents a substituent having a steric parameter value (Es value) of −0.5 or less. R ₆ represents a hydrogen atom or a substituent, n2 is an integer of 1-4. X ₁ -L ₁ -X ₂ represents a bidentate ligand, and X ₁ and X ₂ each independently represent a carbon atom, a nitrogen atom or an oxygen atom. L1 represents an atomic group that forms a bidentate ligand together with X ₁ and X ₂ . m1 represents an integer of 1, 2 or 3, m2 represents an integer of 0, 1 or 2, and m1 + m2 is 2 or 3. M ₁ represents a group 8-10 transition metal element in the periodic table. ] The organic electroluminescent element material according to claim 3, wherein the metal complex represented by the general formula (4) is a metal complex represented by the following general formula (5).

[Wherein, R ₁ , R ₂ , R ₃ and R ₄ each represents a hydrogen atom or a substituent. n1 represents an integer of 1 to 3. R ₅ and R ₇ each represent a substituent having a steric parameter value (Es value) of −0.5 or less. R ₆ represents a hydrogen atom or a substituent, and n2 represents an integer of 1 to 3. X ₁ -L ₁ -X ₂ represents a bidentate ligand, and X ₁ and X ₂ each independently represent a carbon atom, a nitrogen atom or an oxygen atom. L1 represents an atomic group that forms a bidentate ligand together with X ₁ and X ₂ . m1 represents an integer of 1, 2 or 3, m2 represents an integer of 0, 1 or 2, and m1 + m2 is 2 or 3. M ₁ represents a group 8-10 transition metal element in the periodic table. ] The organic electroluminescent element material according to claim 1, wherein the metal complex represented by the general formula (1) is a metal complex represented by the following general formula (6).

[Wherein R ₁ , R ₃ and R ₄ each represents a hydrogen atom or a substituent. n1 represents the integer of 1-4. Z2 represents an atomic group necessary to form a 5-membered or 6-membered hydrocarbon ring group or a 5- to 6-membered heterocyclic group, R ₅ is sterically parameter value (Es value) -0. Represents 5 or less substituents. R ₆ represents a hydrogen atom or a substituent, n2 is an integer of 1-4. X ₁ -L ₁ -X ₂ represents a bidentate ligand, and X ₁ and X ₂ each independently represent a carbon atom, a nitrogen atom or an oxygen atom. L1 represents an atomic group that forms a bidentate ligand together with X ₁ and X ₂ . m1 represents an integer of 1, 2 or 3, m2 represents an integer of 0, 1 or 2, and m1 + m2 is 2 or 3. M ₁ represents a group 8-10 transition metal element in the periodic table. ] The organic electroluminescent element material according to claim 5, wherein the metal complex represented by the general formula (6) is a metal complex represented by the following general formula (7).

[Wherein R ₁ , R ₃ and R ₄ each represents a hydrogen atom or a substituent. n1 represents the integer of 1-4. R ₅ represents a substituent having a steric parameter value (Es value) of −0.5 or less. R ₆ represents a hydrogen atom or a substituent, n2 is an integer of 1-4. X ₁ -L ₁ -X ₂ represents a bidentate ligand, and X ₁ and X ₂ each independently represent a carbon atom, a nitrogen atom or an oxygen atom. L1 represents an atomic group that forms a bidentate ligand together with X ₁ and X ₂ . m1 represents an integer of 1, 2 or 3, m2 represents an integer of 0, 1 or 2, and m1 + m2 is 2 or 3. M ₁ represents a group 8-10 transition metal element in the periodic table. ] The organic electroluminescent element material according to claim 6, wherein the metal complex represented by the general formula (7) is a metal complex represented by the following general formula (8).

[Wherein R ₁ , R ₃ and R ₄ each represents a hydrogen atom or a substituent. n1 represents the integer of 1-4. R ₅ and R ₇ each represent a substituent having a steric parameter value (Es value) of −0.5 or less. R ₆ represents a hydrogen atom or a substituent, n3 denotes an integer of 1 to 3. X ₁ -L ₁ -X ₂ represents a bidentate ligand, and X ₁ and X ₂ each independently represent a carbon atom, a nitrogen atom or an oxygen atom. L1 represents an atomic group that forms a bidentate ligand together with X ₁ and X ₂ . m1 represents an integer of 1, 2 or 3, m2 represents an integer of 0, 1 or 2, and m1 + m2 is 2 or 3. M ₁ which is a central metal represents a transition metal element of Group 8 to Group 10 in the periodic table. ] Bidentate ligand represented by X ₁ -L1-X ₂ is, according to any one of claims 1-7, characterized in that a compound represented by the following general formula (9) Organic electroluminescence element material.

Wherein, Z3, Z4 represents a 5- or 6-membered hydrocarbon ring group or 5-membered or 6-membered heterocyclic group, R _8, R ₉ each represent a hydrogen atom or a substituent. n4 and n5 represent an integer of 1 to 4. R ₁₀ represents a substituent. A represents -C (R1a) = (wherein R1a represents a hydrogen atom or a substituent) or a nitrogen atom. ] Wherein X ₁ 2 bidentate ligand represented by -L1-X ₂ is an organic electroluminescence device material according to claim 8, characterized in that a compound represented by the following general formula (10).

[Wherein R ₈ and R ₉ each represents a hydrogen atom or a substituent. n4 and n5 represent an integer of 1 to 4. R ₁₀ represents a substituent having a steric parameter value (Es value) of −0.5 or less. R ₁₂ represents a hydrogen atom or a substituent, and n6 represents an integer of 1 to 2. ] Wherein X ₁ 2 bidentate ligand represented by -L1-X ₂ is an organic electroluminescence device material according to claim 9, characterized in that a compound represented by the following general formula (11).

[Wherein R ₈ and R ₉ each represents a hydrogen atom or a substituent. n4 and n5 represent an integer of 1 to 4. R ₁₀ and R ₁₁ each represent a substituent having a steric parameter value (Es value) of −0.5 or less. R ₁₂ represents a hydrogen atom or a substituent, and n6 represents an integer of 1 to 2. ] In the metal complex represented by at least one selected from the group consisting of the general formula (1) and the general formulas (3) to (8),
m2 is 0, The organic electroluminescent element material of any one of Claims 1-10 characterized by the above-mentioned. In the metal complex represented by at least one selected from the group consisting of the general formula (1) and the general formulas (3) to (8),
m2 is 1, The organic electroluminescent element material of any one of Claims 1-10 characterized by the above-mentioned. The organic electroluminescence device according to claim 2, wherein the substituent having a steric parameter value (Es value) of −0.5 or less is an electron donating group. material. The organic electroluminescent element material according to claim _1, wherein M ₁ is iridium. The organic electroluminescent element material according to claim _1, wherein M ₁ is platinum. The organic electroluminescence element material according to claim 1, wherein the first emission wavelength is in the range of 400 to 500 nm. The organic electroluminescence according to any one of claims 1 to 16, comprising a polymer having, as a partial structure, a metal complex represented by any one of the general formulas (1) to (8). Element material. The organic electroluminescent element material containing the organic electroluminescent element material of any one of Claims 1-17. The organic electroluminescent element according to claim 18, comprising a light emitting layer as a constituent layer, wherein the light emitting layer contains the organic electroluminescent element material according to claim 1. A light-emitting layer as a constituent layer, and the light-emitting layer contains a carboline derivative or a derivative having a ring structure in which at least one of carbon atoms of a hydrocarbon ring constituting the carboline ring of the carboline derivative is substituted with a nitrogen atom The organic electroluminescent element according to claim 18 or 19, wherein It has a hole blocking layer as a constituent layer, and the hole blocking layer has a ring structure in which at least one of carbon atoms of a carboline derivative or a hydrocarbon ring constituting a carboline ring of the carboline derivative is substituted with a nitrogen atom. 21. The organic electroluminescent device according to claim 18, further comprising a derivative. A display device comprising the organic electroluminescence element according to any one of claims 18 to 21. It has an organic electroluminescent element of any one of Claims 18-21, The illuminating device characterized by the above-mentioned.

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